add tests

add an admin endpoint for authorizing server to signal token revocations
Rename pagination&purge locks and add comments explaining them (#16112 )
2023-08-16 15:06:03 -07:00 · 2023-08-16 15:05:54 -07:00 · 2023-08-16 12:02:11 -07:00 · 2023-08-16 12:02:11 -07:00 · 2023-08-16 12:02:11 -07:00 · 2023-08-16 12:02:11 -07:00
332 changed files with 16953 additions and 8548 deletions
@@ -29,11 +29,12 @@ IS_PR = os.environ["GITHUB_REF"].startswith("refs/pull/")

 # First calculate the various trial jobs.
 #
-# For each type of test we only run on Py3.7 on PRs
+# For PRs, we only run each type of test with the oldest Python version supported (which
+# is Python 3.8 right now)

 trial_sqlite_tests = [
    {
-        "python-version": "3.7",
+        "python-version": "3.8",
        "database": "sqlite",
        "extras": "all",
    }
@@ -46,13 +47,13 @@ if not IS_PR:
            "database": "sqlite",
            "extras": "all",
        }
-        for version in ("3.8", "3.9", "3.10", "3.11")
+        for version in ("3.9", "3.10", "3.11")
    )


 trial_postgres_tests = [
    {
-        "python-version": "3.7",
+        "python-version": "3.8",
        "database": "postgres",
        "postgres-version": "11",
        "extras": "all",
@@ -71,7 +72,7 @@ if not IS_PR:

 trial_no_extra_tests = [
    {
-        "python-version": "3.7",
+        "python-version": "3.8",
        "database": "sqlite",
        "extras": "",
    }
@@ -133,11 +134,6 @@ if not IS_PR:
                "sytest-tag": "testing",
                "postgres": "postgres",
            },
-            {
-                "sytest-tag": "buster",
-                "postgres": "multi-postgres",
-                "workers": "workers",
-            },
        ]
    )

@@ -29,6 +29,16 @@ jobs:
      - name: Inspect builder
        run: docker buildx inspect

+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Extract version from pyproject.toml
+        # Note: explicitly requesting bash will mean bash is invoked with `-eo pipefail`, see
+        # https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsshell
+        shell: bash
+        run: |
+          echo "SYNAPSE_VERSION=$(grep "^version" pyproject.toml | sed -E 's/version\s*=\s*["]([^"]*)["]/\1/')" >> $GITHUB_ENV
+
      - name: Log in to DockerHub
        uses: docker/login-action@v2
        with:
@@ -61,7 +71,9 @@ jobs:
        uses: docker/build-push-action@v4
        with:
          push: true
-          labels: "gitsha1=${{ github.sha }}"
+          labels: |
+            gitsha1=${{ github.sha }}
+            org.opencontainers.image.version=${{ env.SYNAPSE_VERSION }}
          tags: "${{ steps.set-tag.outputs.tags }}"
          file: "docker/Dockerfile"
          platforms: linux/amd64,linux/arm64
@@ -22,7 +22,21 @@ concurrency:
  cancel-in-progress: true

 jobs:
+  check_repo:
+    # Prevent this workflow from running on any fork of Synapse other than matrix-org/synapse, as it is
+    # only useful to the Synapse core team.
+    # All other workflow steps depend on this one, thus if 'should_run_workflow' is not 'true', the rest
+    # of the workflow will be skipped as well.
+    runs-on: ubuntu-latest
+    outputs:
+      should_run_workflow: ${{ steps.check_condition.outputs.should_run_workflow }}
+    steps:
+      - id: check_condition
+        run: echo "should_run_workflow=${{ github.repository == 'matrix-org/synapse' }}" >> "$GITHUB_OUTPUT"
+
  mypy:
+    needs: check_repo
+    if: needs.check_repo.outputs.should_run_workflow == 'true'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
@@ -47,6 +61,8 @@ jobs:
        run: sed '/warn_unused_ignores = True/d' -i mypy.ini
      - run: poetry run mypy
  trial:
+    needs: check_repo
+    if: needs.check_repo.outputs.should_run_workflow == 'true'
    runs-on: ubuntu-latest
    strategy:
      matrix:
@@ -105,6 +121,8 @@ jobs:


  sytest:
+    needs: check_repo
+    if: needs.check_repo.outputs.should_run_workflow == 'true'
    runs-on: ubuntu-latest
    container:
      image: matrixdotorg/sytest-synapse:testing
@@ -156,7 +174,8 @@ jobs:


  complement:
-    if: "${{ !failure() && !cancelled() }}"
+    needs: check_repo
+    if: "!failure() && !cancelled() && needs.check_repo.outputs.should_run_workflow == 'true'"
    runs-on: ubuntu-latest

    strategy:
@@ -192,7 +211,7 @@ jobs:
  # Open an issue if the build fails, so we know about it.
  # Only do this if we're not experimenting with this action in a PR.
  open-issue:
-    if: "failure() && github.event_name != 'push' && github.event_name != 'pull_request'"
+    if: "failure() && github.event_name != 'push' && github.event_name != 'pull_request' && needs.check_repo.outputs.should_run_workflow == 'true'"
    needs:
      # TODO: should mypy be included here? It feels more brittle than the others.
      - mypy
@@ -34,6 +34,7 @@ jobs:
      - id: set-distros
        run: |
          # if we're running from a tag, get the full list of distros; otherwise just use debian:sid
+          # NOTE: inside the actual Dockerfile-dhvirtualenv, the image name is expanded into its full image path
          dists='["debian:sid"]'
          if [[ $GITHUB_REF == refs/tags/* ]]; then
              dists=$(scripts-dev/build_debian_packages.py --show-dists-json)
@@ -143,7 +144,7 @@ jobs:

      - name: Only build a single wheel on PR
        if: startsWith(github.ref, 'refs/pull/')
-        run: echo "CIBW_BUILD="cp37-manylinux_${{ matrix.arch }}"" >> $GITHUB_ENV
+        run: echo "CIBW_BUILD="cp38-manylinux_${{ matrix.arch }}"" >> $GITHUB_ENV

      - name: Build wheels
        run: python -m cibuildwheel --output-dir wheelhouse
@@ -35,7 +35,7 @@ jobs:
    steps:
      - uses: actions/checkout@v3
      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
      - uses: Swatinem/rust-cache@v2
      - uses: matrix-org/setup-python-poetry@v1
        with:
@@ -92,6 +92,10 @@ jobs:
      - name: Checkout repository
        uses: actions/checkout@v3

+      - name: Install Rust
+        uses: dtolnay/rust-toolchain@1.60.0
+      - uses: Swatinem/rust-cache@v2
+
      - name: Setup Poetry
        uses: matrix-org/setup-python-poetry@v1
        with:
@@ -103,10 +107,6 @@ jobs:
          # To make CI green, err towards caution and install the project.
          install-project: "true"

-      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
-      - uses: Swatinem/rust-cache@v2
-
      # Cribbed from
      # https://github.com/AustinScola/mypy-cache-github-action/blob/85ea4f2972abed39b33bd02c36e341b28ca59213/src/restore.ts#L10-L17
      - name: Restore/persist mypy's cache
@@ -150,7 +150,7 @@ jobs:
        with:
          ref: ${{ github.event.pull_request.head.sha }}
      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
      - uses: Swatinem/rust-cache@v2
      - uses: matrix-org/setup-python-poetry@v1
        with:
@@ -167,7 +167,7 @@ jobs:
      - uses: actions/checkout@v3

      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
        with:
            components: clippy
      - uses: Swatinem/rust-cache@v2
@@ -268,7 +268,7 @@ jobs:
            postgres:${{ matrix.job.postgres-version }}

      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
      - uses: Swatinem/rust-cache@v2

      - uses: matrix-org/setup-python-poetry@v1
@@ -308,7 +308,7 @@ jobs:
      - uses: actions/checkout@v3

      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
      - uses: Swatinem/rust-cache@v2

      # There aren't wheels for some of the older deps, so we need to install
@@ -320,7 +320,7 @@ jobs:

      - uses: actions/setup-python@v4
        with:
-          python-version: '3.7'
+          python-version: '3.8'

      - name: Prepare old deps
        if: steps.cache-poetry-old-deps.outputs.cache-hit != 'true'
@@ -362,7 +362,7 @@ jobs:
    runs-on: ubuntu-latest
    strategy:
      matrix:
-        python-version: ["pypy-3.7"]
+        python-version: ["pypy-3.8"]
        extras: ["all"]

    steps:
@@ -399,8 +399,8 @@ jobs:
      env:
        SYTEST_BRANCH: ${{ github.head_ref }}
        POSTGRES: ${{ matrix.job.postgres && 1}}
-        MULTI_POSTGRES: ${{ (matrix.job.postgres == 'multi-postgres') && 1}}
-        ASYNCIO_REACTOR: ${{ (matrix.job.reactor == 'asyncio') && 1 }}
+        MULTI_POSTGRES: ${{ (matrix.job.postgres == 'multi-postgres') || '' }}
+        ASYNCIO_REACTOR: ${{ (matrix.job.reactor == 'asyncio') || '' }}
        WORKERS: ${{ matrix.job.workers && 1 }}
        BLACKLIST: ${{ matrix.job.workers && 'synapse-blacklist-with-workers' }}
        TOP: ${{ github.workspace }}
@@ -416,7 +416,7 @@ jobs:
        run: cat sytest-blacklist .ci/worker-blacklist > synapse-blacklist-with-workers

      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
      - uses: Swatinem/rust-cache@v2

      - name: Run SyTest
@@ -477,7 +477,7 @@ jobs:
    strategy:
      matrix:
        include:
-          - python-version: "3.7"
+          - python-version: "3.8"
            postgres-version: "11"

          - python-version: "3.11"
@@ -556,7 +556,7 @@ jobs:
          path: synapse

      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
      - uses: Swatinem/rust-cache@v2

      - uses: actions/setup-go@v4
@@ -584,7 +584,7 @@ jobs:
      - uses: actions/checkout@v3

      - name: Install Rust
-        uses: dtolnay/rust-toolchain@1.58.1
+        uses: dtolnay/rust-toolchain@1.60.0
      - uses: Swatinem/rust-cache@v2

      - run: cargo test
@@ -5,6 +5,9 @@ on:
    - cron: 0 8 * * *

  workflow_dispatch:
+    # NB: inputs are only present when this workflow is dispatched manually.
+    # (The default below is the default field value in the form to trigger
+    # a manual dispatch). Otherwise the inputs will evaluate to null.
    inputs:
      twisted_ref:
        description: Commit, branch or tag to checkout from upstream Twisted.
@@ -18,7 +21,22 @@ concurrency:
  cancel-in-progress: true

 jobs:
+  check_repo:
+    # Prevent this workflow from running on any fork of Synapse other than matrix-org/synapse, as it is
+    # only useful to the Synapse core team.
+    # All other workflow steps depend on this one, thus if 'should_run_workflow' is not 'true', the rest
+    # of the workflow will be skipped as well.
+    if: github.repository == 'matrix-org/synapse'
+    runs-on: ubuntu-latest
+    outputs:
+      should_run_workflow: ${{ steps.check_condition.outputs.should_run_workflow }}
+    steps:
+      - id: check_condition
+        run: echo "should_run_workflow=${{ github.repository == 'matrix-org/synapse' }}" >> "$GITHUB_OUTPUT"
+
  mypy:
+    needs: check_repo
+    if: needs.check_repo.outputs.should_run_workflow == 'true'
    runs-on: ubuntu-latest

    steps:
@@ -34,13 +52,15 @@ jobs:
          extras: "all"
      - run: |
          poetry remove twisted
-          poetry add --extras tls git+https://github.com/twisted/twisted.git#${{ inputs.twisted_ref }}
+          poetry add --extras tls git+https://github.com/twisted/twisted.git#${{ inputs.twisted_ref || 'trunk' }}
          poetry install --no-interaction --extras "all test"
      - name: Remove warn_unused_ignores from mypy config
        run: sed '/warn_unused_ignores = True/d' -i mypy.ini
      - run: poetry run mypy

  trial:
+    needs: check_repo
+    if: needs.check_repo.outputs.should_run_workflow == 'true'
    runs-on: ubuntu-latest

    steps:
@@ -75,9 +95,15 @@ jobs:
          || true

  sytest:
+    needs: check_repo
+    if: needs.check_repo.outputs.should_run_workflow == 'true'
    runs-on: ubuntu-latest
    container:
-      image: matrixdotorg/sytest-synapse:buster
+      # We're using ubuntu:focal because it uses Python 3.8 which is our minimum supported Python version.
+      # This job is a canary to warn us about unreleased twisted changes that would cause problems for us if
+      # they were to be released immediately. For simplicity's sake (and to save CI runners) we use the oldest
+      # version, assuming that any incompatibilities on newer versions would also be present on the oldest.
+      image: matrixdotorg/sytest-synapse:focal
      volumes:
        - ${{ github.workspace }}:/src

@@ -119,7 +145,8 @@ jobs:
            /logs/**/*.log*

  complement:
-    if: "${{ !failure() && !cancelled() }}"
+    needs: check_repo
+    if: "!failure() && !cancelled() && needs.check_repo.outputs.should_run_workflow == 'true'"
    runs-on: ubuntu-latest

    strategy:
@@ -166,7 +193,7 @@ jobs:

  # open an issue if the build fails, so we know about it.
  open-issue:
-    if: failure()
+    if: failure() && needs.check_repo.outputs.should_run_workflow == 'true'
    needs:
      - mypy
      - trial
@@ -34,6 +34,7 @@ __pycache__/
 /logs
 /media_store/
 /uploads
+/homeserver-config-overrides.d

 # For direnv users
 /.envrc
@@ -4,18 +4,18 @@ version = 3

 [[package]]
 name = "aho-corasick"
-version = "0.7.19"
+version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b4f55bd91a0978cbfd91c457a164bab8b4001c833b7f323132c0a4e1922dd44e"
+checksum = "43f6cb1bf222025340178f382c426f13757b2960e89779dfcb319c32542a5a41"
 dependencies = [
 "memchr",
 ]

 [[package]]
 name = "anyhow"
-version = "1.0.71"
+version = "1.0.72"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c7d0618f0e0b7e8ff11427422b64564d5fb0be1940354bfe2e0529b18a9d9b8"
+checksum = "3b13c32d80ecc7ab747b80c3784bce54ee8a7a0cc4fbda9bf4cda2cf6fe90854"

 [[package]]
 name = "arc-swap"
@@ -132,9 +132,9 @@ dependencies = [

 [[package]]
 name = "log"
-version = "0.4.18"
+version = "0.4.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "518ef76f2f87365916b142844c16d8fefd85039bc5699050210a7778ee1cd1de"
+checksum = "b5e6163cb8c49088c2c36f57875e58ccd8c87c7427f7fbd50ea6710b2f3f2e8f"

 [[package]]
 name = "memchr"
@@ -182,9 +182,9 @@ dependencies = [

 [[package]]
 name = "proc-macro2"
-version = "1.0.52"
+version = "1.0.64"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1d0e1ae9e836cc3beddd63db0df682593d7e2d3d891ae8c9083d2113e1744224"
+checksum = "78803b62cbf1f46fde80d7c0e803111524b9877184cfe7c3033659490ac7a7da"
 dependencies = [
 "unicode-ident",
 ]
@@ -229,9 +229,9 @@ dependencies = [

 [[package]]
 name = "pyo3-log"
-version = "0.8.1"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f9c8b57fe71fb5dcf38970ebedc2b1531cf1c14b1b9b4c560a182a57e115575c"
+checksum = "f47b0777feb17f61eea78667d61103758b243a871edc09a7786500a50467b605"
 dependencies = [
 "arc-swap",
 "log",
@@ -273,9 +273,9 @@ dependencies = [

 [[package]]
 name = "quote"
-version = "1.0.26"
+version = "1.0.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4424af4bf778aae2051a77b60283332f386554255d722233d09fbfc7e30da2fc"
+checksum = "573015e8ab27661678357f27dc26460738fd2b6c86e46f386fde94cb5d913105"
 dependencies = [
 "proc-macro2",
 ]
@@ -291,9 +291,21 @@ dependencies = [

 [[package]]
 name = "regex"
-version = "1.7.3"
+version = "1.9.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8b1f693b24f6ac912f4893ef08244d70b6067480d2f1a46e950c9691e6749d1d"
+checksum = "81bc1d4caf89fac26a70747fe603c130093b53c773888797a6329091246d651a"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fed1ceff11a1dddaee50c9dc8e4938bd106e9d89ae372f192311e7da498e3b69"
 dependencies = [
 "aho-corasick",
 "memchr",
@@ -302,9 +314,9 @@ dependencies = [

 [[package]]
 name = "regex-syntax"
-version = "0.6.29"
+version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f162c6dd7b008981e4d40210aca20b4bd0f9b60ca9271061b07f78537722f2e1"
+checksum = "e5ea92a5b6195c6ef2a0295ea818b312502c6fc94dde986c5553242e18fd4ce2"

 [[package]]
 name = "ryu"
@@ -320,29 +332,29 @@ checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"

 [[package]]
 name = "serde"
-version = "1.0.163"
+version = "1.0.183"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2113ab51b87a539ae008b5c6c02dc020ffa39afd2d83cffcb3f4eb2722cebec2"
+checksum = "32ac8da02677876d532745a130fc9d8e6edfa81a269b107c5b00829b91d8eb3c"
 dependencies = [
 "serde_derive",
 ]

 [[package]]
 name = "serde_derive"
-version = "1.0.163"
+version = "1.0.183"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8c805777e3930c8883389c602315a24224bcc738b63905ef87cd1420353ea93e"
+checksum = "aafe972d60b0b9bee71a91b92fee2d4fb3c9d7e8f6b179aa99f27203d99a4816"
 dependencies = [
 "proc-macro2",
 "quote",
- "syn 2.0.10",
+ "syn 2.0.28",
 ]

 [[package]]
 name = "serde_json"
-version = "1.0.96"
+version = "1.0.104"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "057d394a50403bcac12672b2b18fb387ab6d289d957dab67dd201875391e52f1"
+checksum = "076066c5f1078eac5b722a31827a8832fe108bed65dfa75e233c89f8206e976c"
 dependencies = [
 "itoa",
 "ryu",
@@ -374,9 +386,9 @@ dependencies = [

 [[package]]
 name = "syn"
-version = "2.0.10"
+version = "2.0.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5aad1363ed6d37b84299588d62d3a7d95b5a5c2d9aad5c85609fda12afaa1f40"
+checksum = "04361975b3f5e348b2189d8dc55bc942f278b2d482a6a0365de5bdd62d351567"
 dependencies = [
 "proc-macro2",
 "quote",
@@ -3,3 +3,4 @@

 [workspace]
 members = ["rust"]
+resolver = "2"
@@ -0,0 +1 @@
+Implements an admin API to lock an user without deactivating them. Based on [MSC3939](https://github.com/matrix-org/matrix-spec-proposals/pull/3939).
@@ -0,0 +1 @@
+Update dehydrated devices implementation.
@@ -0,0 +1 @@
+Fix long-standing bug where concurrent requests to change a user's push rules could cause a deadlock. Contributed by Nick @ Beeper (@fizzadar).
@@ -0,0 +1 @@
+Fix the type annotation on `run_db_interaction` in the Module API.
@@ -0,0 +1 @@
+Structured logging docs: add a link to explain the ELK stack
@@ -0,0 +1 @@
+Clean-up the presence code.
@@ -0,0 +1 @@
+Allow customising the IdP display name, icon, and brand for SAML and CAS providers (in addition to OIDC provider).
@@ -0,0 +1 @@
+Run `pyupgrade` for Python 3.8+.
@@ -0,0 +1 @@
+Rename pagination and purge locks and add comments to explain why they exist and how they work.
@@ -0,0 +1 @@
+Attempt to fix the twisted trunk job.
@@ -0,0 +1 @@
+Cache token introspection response from OIDC provider.
@@ -769,7 +769,7 @@ def main(server_url, identity_server_url, username, token, config_path):
    global CONFIG_JSON
    CONFIG_JSON = config_path  # bit cheeky, but just overwrite the global
    try:
-        with open(config_path, "r") as config:
+        with open(config_path) as config:
            syn_cmd.config = json.load(config)
            try:
                http_client.verbose = "on" == syn_cmd.config["verbose"]
@@ -29,7 +29,7 @@
        "level": "error"
      },
      {
-        "line": "my-matrix-server-federation-sender-1 | 2023-01-25 20:56:20,995 - synapse.http.matrixfederationclient - 709 - WARNING - federation_transaction_transmission_loop-3 - {PUT-O-3} [example.com] Request failed: PUT matrix://example.com/_matrix/federation/v1/send/1674680155797: HttpResponseException('403: Forbidden')",
+        "line": "my-matrix-server-federation-sender-1 | 2023-01-25 20:56:20,995 - synapse.http.matrixfederationclient - 709 - WARNING - federation_transaction_transmission_loop-3 - {PUT-O-3} [example.com] Request failed: PUT matrix-federation://example.com/_matrix/federation/v1/send/1674680155797: HttpResponseException('403: Forbidden')",
        "level": "warning"
      },
      {
@@ -1,3 +1,87 @@
+matrix-synapse-py3 (1.90.0) stable; urgency=medium
+
+  * New Synapse release 1.90.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 15 Aug 2023 11:17:34 +0100
+
+matrix-synapse-py3 (1.90.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.90.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 08 Aug 2023 15:29:34 +0100
+
+matrix-synapse-py3 (1.89.0) stable; urgency=medium
+
+  * New Synapse release 1.89.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 01 Aug 2023 11:07:15 +0100
+
+matrix-synapse-py3 (1.89.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.89.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 25 Jul 2023 14:31:07 +0200
+
+matrix-synapse-py3 (1.88.0) stable; urgency=medium
+
+  * New Synapse release 1.88.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 18 Jul 2023 13:59:28 +0100
+
+matrix-synapse-py3 (1.88.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.88.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 11 Jul 2023 10:20:19 +0100
+
+matrix-synapse-py3 (1.87.0) stable; urgency=medium
+
+  * New Synapse release 1.87.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 04 Jul 2023 16:24:00 +0100
+
+matrix-synapse-py3 (1.87.0~rc1) stable; urgency=medium
+
+  * New synapse release 1.87.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 27 Jun 2023 15:27:04 +0000
+
+matrix-synapse-py3 (1.86.0) stable; urgency=medium
+
+  * New Synapse release 1.86.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 20 Jun 2023 17:22:46 +0200
+
+matrix-synapse-py3 (1.86.0~rc2) stable; urgency=medium
+
+  * New Synapse release 1.86.0rc2.
+
+ -- Synapse Packaging team <packages@matrix.org>  Wed, 14 Jun 2023 12:16:27 +0200
+
+matrix-synapse-py3 (1.86.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.86.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 13 Jun 2023 14:30:45 +0200
+
+matrix-synapse-py3 (1.85.2) stable; urgency=medium
+
+  * New Synapse release 1.85.2.
+
+ -- Synapse Packaging team <packages@matrix.org>  Thu, 08 Jun 2023 13:04:18 +0100
+
+matrix-synapse-py3 (1.85.1) stable; urgency=medium
+
+  * New Synapse release 1.85.1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Wed, 07 Jun 2023 10:51:12 +0100
+
+matrix-synapse-py3 (1.85.0) stable; urgency=medium
+
+  * New Synapse release 1.85.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 06 Jun 2023 09:39:29 +0100
+
 matrix-synapse-py3 (1.85.0~rc2) stable; urgency=medium

  * New Synapse release 1.85.0rc2.
@@ -27,7 +27,7 @@ ARG PYTHON_VERSION=3.11
 ###
 # We hardcode the use of Debian bullseye here because this could change upstream
 # and other Dockerfiles used for testing are expecting bullseye.
-FROM docker.io/python:${PYTHON_VERSION}-slim-bullseye as requirements
+FROM docker.io/library/python:${PYTHON_VERSION}-slim-bullseye as requirements

 # RUN --mount is specific to buildkit and is documented at
 # https://github.com/moby/buildkit/blob/master/frontend/dockerfile/docs/syntax.md#build-mounts-run---mount.
@@ -87,7 +87,7 @@ RUN if [ -z "$TEST_ONLY_IGNORE_POETRY_LOCKFILE" ]; then \
 ###
 ### Stage 1: builder
 ###
-FROM docker.io/python:${PYTHON_VERSION}-slim-bullseye as builder
+FROM docker.io/library/python:${PYTHON_VERSION}-slim-bullseye as builder

 # install the OS build deps
 RUN \
@@ -158,7 +158,7 @@ RUN --mount=type=cache,target=/synapse/target,sharing=locked \
 ### Stage 2: runtime
 ###

-FROM docker.io/python:${PYTHON_VERSION}-slim-bullseye
+FROM docker.io/library/python:${PYTHON_VERSION}-slim-bullseye

 LABEL org.opencontainers.image.url='https://matrix.org/docs/projects/server/synapse'
 LABEL org.opencontainers.image.documentation='https://github.com/matrix-org/synapse/blob/master/docker/README.md'
@@ -24,16 +24,16 @@ ARG distro=""
 # https://launchpad.net/~jyrki-pulliainen/+archive/ubuntu/dh-virtualenv, but
 # it's not obviously easier to use that than to build our own.)

-FROM ${distro} as builder
+FROM docker.io/library/${distro} as builder

 RUN apt-get update -qq -o Acquire::Languages=none
 RUN env DEBIAN_FRONTEND=noninteractive apt-get install \
-        -yqq --no-install-recommends \
-        build-essential \
-        ca-certificates \
-        devscripts \
-        equivs \
-        wget
+    -yqq --no-install-recommends \
+    build-essential \
+    ca-certificates \
+    devscripts \
+    equivs \
+    wget

 # fetch and unpack the package
 # We are temporarily using a fork of dh-virtualenv due to an incompatibility with Python 3.11, which ships with
@@ -55,40 +55,36 @@ RUN cd /dh-virtualenv && DEB_BUILD_OPTIONS=nodoc dpkg-buildpackage -us -uc -b
 ###
 ### Stage 1
 ###
-FROM ${distro}
+FROM docker.io/library/${distro}

 # Get the distro we want to pull from as a dynamic build variable
 # (We need to define it in each build stage)
 ARG distro=""
 ENV distro ${distro}

-# Python < 3.7 assumes LANG="C" means ASCII-only and throws on printing unicode
-# http://bugs.python.org/issue19846
-ENV LANG C.UTF-8
-
 # Install the build dependencies
 #
 # NB: keep this list in sync with the list of build-deps in debian/control
 # TODO: it would be nice to do that automatically.
 RUN apt-get update -qq -o Acquire::Languages=none \
    && env DEBIAN_FRONTEND=noninteractive apt-get install \
-        -yqq --no-install-recommends -o Dpkg::Options::=--force-unsafe-io \
-        build-essential \
-        curl \
-        debhelper \
-        devscripts \
-        libsystemd-dev \
-        lsb-release \
-        pkg-config \
-        python3-dev \
-        python3-pip \
-        python3-setuptools \
-        python3-venv \
-        sqlite3 \
-        libpq-dev \
-        libicu-dev \
-        pkg-config \
-        xmlsec1
+    -yqq --no-install-recommends -o Dpkg::Options::=--force-unsafe-io \
+    build-essential \
+    curl \
+    debhelper \
+    devscripts \
+    libsystemd-dev \
+    lsb-release \
+    pkg-config \
+    python3-dev \
+    python3-pip \
+    python3-setuptools \
+    python3-venv \
+    sqlite3 \
+    libpq-dev \
+    libicu-dev \
+    pkg-config \
+    xmlsec1

 # Install rust and ensure it's in the PATH
 ENV RUSTUP_HOME=/rust
@@ -7,7 +7,7 @@ ARG FROM=matrixdotorg/synapse:$SYNAPSE_VERSION
 # target image. For repeated rebuilds, this is much faster than apt installing
 # each time.

-FROM debian:bullseye-slim AS deps_base
+FROM docker.io/library/debian:bullseye-slim AS deps_base
    RUN \
       --mount=type=cache,target=/var/cache/apt,sharing=locked \
       --mount=type=cache,target=/var/lib/apt,sharing=locked \
@@ -21,7 +21,7 @@ FROM debian:bullseye-slim AS deps_base
 # which makes it much easier to copy (but we need to make sure we use an image
 # based on the same debian version as the synapse image, to make sure we get
 # the expected version of libc.
-FROM redis:6-bullseye AS redis_base
+FROM docker.io/library/redis:7-bullseye AS redis_base

 # now build the final image, based on the the regular Synapse docker image
 FROM $FROM
@@ -73,7 +73,8 @@ The following environment variables are supported in `generate` mode:
  will log sensitive information such as access tokens.
  This should not be needed unless you are a developer attempting to debug something
  particularly tricky.
-
+* `SYNAPSE_LOG_TESTING`: if set, Synapse will log additional information useful
+  for testing.

 ## Postgres

@@ -7,6 +7,7 @@
 # https://github.com/matrix-org/synapse/blob/develop/docker/README-testing.md#testing-with-postgresql-and-single-or-multi-process-synapse

 ARG SYNAPSE_VERSION=latest
+# This is an intermediate image, to be built locally (not pulled from a registry).
 ARG FROM=matrixdotorg/synapse-workers:$SYNAPSE_VERSION

 FROM $FROM
@@ -19,8 +20,8 @@ FROM $FROM
    # the same debian version as Synapse's docker image (so the versions of the
    # shared libraries match).
    RUN adduser --system --uid 999 postgres --home /var/lib/postgresql
-    COPY --from=postgres:13-bullseye /usr/lib/postgresql /usr/lib/postgresql
-    COPY --from=postgres:13-bullseye /usr/share/postgresql /usr/share/postgresql
+    COPY --from=docker.io/library/postgres:13-bullseye /usr/lib/postgresql /usr/lib/postgresql
+    COPY --from=docker.io/library/postgres:13-bullseye /usr/share/postgresql /usr/share/postgresql
    RUN mkdir /var/run/postgresql && chown postgres /var/run/postgresql
    ENV PATH="${PATH}:/usr/lib/postgresql/13/bin"
    ENV PGDATA=/var/lib/postgresql/data
@@ -92,8 +92,6 @@ allow_device_name_lookup_over_federation: true
 ## Experimental Features ##

 experimental_features:
-  # Enable history backfilling support
-  msc2716_enabled: true
  # client-side support for partial state in /send_join responses
  faster_joins: true
  # Enable support for polls
@@ -35,7 +35,11 @@ server {

    # Send all other traffic to the main process
    location ~* ^(\\/_matrix|\\/_synapse) {
+{% if using_unix_sockets %}
+        proxy_pass http://unix:/run/main_public.sock;
+{% else %}
        proxy_pass http://localhost:8080;
+{% endif %}
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Host $host;
@@ -6,6 +6,9 @@
 {% if enable_redis %}
 redis:
    enabled: true
+    {% if using_unix_sockets %}
+    path: /tmp/redis.sock
+    {% endif %}
 {% endif %}

 {% if appservice_registrations is not none %}
@@ -19,7 +19,11 @@ username=www-data
 autorestart=true

 [program:redis]
+{% if using_unix_sockets %}
+command=/usr/local/bin/prefix-log /usr/local/bin/redis-server --unixsocket /tmp/redis.sock
+{% else %}
 command=/usr/local/bin/prefix-log /usr/local/bin/redis-server
+{% endif %}
 priority=1
 stdout_logfile=/dev/stdout
 stdout_logfile_maxbytes=0
@@ -8,7 +8,11 @@ worker_name: "{{ name }}"

 worker_listeners:
  - type: http
+{% if using_unix_sockets %}
+    path: "/run/worker.{{ port }}"
+{% else %}
    port: {{ port }}
+{% endif %}
 {% if listener_resources %}
    resources:
      - names:
@@ -36,12 +36,17 @@ listeners:

  # Allow configuring in case we want to reverse proxy 8008
  # using another process in the same container
+{% if SYNAPSE_USE_UNIX_SOCKET %}
+  # Unix sockets don't care about TLS or IP addresses or ports
+  - path: '/run/main_public.sock'
+    type: http
+{% else %}
  - port: {{ SYNAPSE_HTTP_PORT or 8008 }}
    tls: false
    bind_addresses: ['::']
    type: http
    x_forwarded: false
-
+{% endif %}
    resources:
      - names: [client]
        compress: true
@@ -57,8 +62,11 @@ database:
    user: "{{ POSTGRES_USER or "synapse" }}"
    password: "{{ POSTGRES_PASSWORD }}"
    database: "{{ POSTGRES_DB or "synapse" }}"
+{% if not SYNAPSE_USE_UNIX_SOCKET %}
+{# Synapse will use a default unix socket for Postgres when host/port is not specified (behavior from `psycopg2`). #}
    host: "{{ POSTGRES_HOST or "db" }}"
    port: "{{ POSTGRES_PORT or "5432" }}"
+{% endif %}
    cp_min: 5
    cp_max: 10
 {% else %}
@@ -49,17 +49,35 @@ handlers:
    class: logging.StreamHandler
    formatter: precise

-{% if not SYNAPSE_LOG_SENSITIVE %}
-{#
-  If SYNAPSE_LOG_SENSITIVE is unset, then override synapse.storage.SQL to INFO
-  so that DEBUG entries (containing sensitive information) are not emitted.
-#}
 loggers:
+    # This is just here so we can leave `loggers` in the config regardless of whether
+    # we configure other loggers below (avoid empty yaml dict error).
+    _placeholder:
+        level: "INFO"
+
+    {% if not SYNAPSE_LOG_SENSITIVE %}
+    {#
+      If SYNAPSE_LOG_SENSITIVE is unset, then override synapse.storage.SQL to INFO
+      so that DEBUG entries (containing sensitive information) are not emitted.
+    #}
    synapse.storage.SQL:
        # beware: increasing this to DEBUG will make synapse log sensitive
        # information such as access tokens.
        level: INFO
-{% endif %}
+    {% endif %}
+
+    {% if SYNAPSE_LOG_TESTING %}
+    {#
+      If Synapse is under test, log a few more useful things for a developer
+      attempting to debug something particularly tricky.
+
+      With `synapse.visibility.filtered_event_debug`, it logs when events are (maybe
+      unexpectedly) filtered out of responses in tests. It's just nice to be able to
+      look at the CI log and figure out why an event isn't being returned.
+    #}
+    synapse.visibility.filtered_event_debug:
+        level: DEBUG
+    {% endif %}

 root:
    level: {{ SYNAPSE_LOG_LEVEL or "INFO" }}
@@ -40,6 +40,8 @@
 #         log level. INFO is the default.
 #   * SYNAPSE_LOG_SENSITIVE: If unset, SQL and SQL values won't be logged,
 #         regardless of the SYNAPSE_LOG_LEVEL setting.
+#   * SYNAPSE_LOG_TESTING: if set, Synapse will log additional information useful
+#     for testing.
 #
 # NOTE: According to Complement's ENTRYPOINT expectations for a homeserver image (as defined
 # in the project's README), this script may be run multiple times, and functionality should
@@ -72,6 +74,9 @@ MAIN_PROCESS_HTTP_LISTENER_PORT = 8080
 MAIN_PROCESS_INSTANCE_NAME = "main"
 MAIN_PROCESS_LOCALHOST_ADDRESS = "127.0.0.1"
 MAIN_PROCESS_REPLICATION_PORT = 9093
+# Obviously, these would only be used with the UNIX socket option
+MAIN_PROCESS_UNIX_SOCKET_PUBLIC_PATH = "/run/main_public.sock"
+MAIN_PROCESS_UNIX_SOCKET_PRIVATE_PATH = "/run/main_private.sock"

 # A simple name used as a placeholder in the WORKERS_CONFIG below. This will be replaced
 # during processing with the name of the worker.
@@ -242,7 +247,6 @@ WORKERS_CONFIG: Dict[str, Dict[str, Any]] = {
            "^/_matrix/client/(api/v1|r0|v3|unstable)/join/",
            "^/_matrix/client/(api/v1|r0|v3|unstable)/knock/",
            "^/_matrix/client/(api/v1|r0|v3|unstable)/profile/",
-            "^/_matrix/client/(v1|unstable/org.matrix.msc2716)/rooms/.*/batch_send",
        ],
        "shared_extra_conf": {},
        "worker_extra_conf": "",
@@ -406,11 +410,15 @@ def add_worker_roles_to_shared_config(
        )

        # Map of stream writer instance names to host/ports combos
-        instance_map[worker_name] = {
-            "host": "localhost",
-            "port": worker_port,
-        }
-
+        if os.environ.get("SYNAPSE_USE_UNIX_SOCKET", False):
+            instance_map[worker_name] = {
+                "path": f"/run/worker.{worker_port}",
+            }
+        else:
+            instance_map[worker_name] = {
+                "host": "localhost",
+                "port": worker_port,
+            }
    # Update the list of stream writers. It's convenient that the name of the worker
    # type is the same as the stream to write. Iterate over the whole list in case there
    # is more than one.
@@ -422,10 +430,15 @@ def add_worker_roles_to_shared_config(

            # Map of stream writer instance names to host/ports combos
            # For now, all stream writers need http replication ports
-            instance_map[worker_name] = {
-                "host": "localhost",
-                "port": worker_port,
-            }
+            if os.environ.get("SYNAPSE_USE_UNIX_SOCKET", False):
+                instance_map[worker_name] = {
+                    "path": f"/run/worker.{worker_port}",
+                }
+            else:
+                instance_map[worker_name] = {
+                    "host": "localhost",
+                    "port": worker_port,
+                }


 def merge_worker_template_configs(
@@ -717,17 +730,29 @@ def generate_worker_files(
    # Note that yaml cares about indentation, so care should be taken to insert lines
    # into files at the correct indentation below.

+    # Convenience helper for if using unix sockets instead of host:port
+    using_unix_sockets = environ.get("SYNAPSE_USE_UNIX_SOCKET", False)
    # First read the original config file and extract the listeners block. Then we'll
    # add another listener for replication. Later we'll write out the result to the
    # shared config file.
-    listeners = [
-        {
-            "port": MAIN_PROCESS_REPLICATION_PORT,
-            "bind_address": MAIN_PROCESS_LOCALHOST_ADDRESS,
-            "type": "http",
-            "resources": [{"names": ["replication"]}],
-        }
-    ]
+    listeners: List[Any]
+    if using_unix_sockets:
+        listeners = [
+            {
+                "path": MAIN_PROCESS_UNIX_SOCKET_PRIVATE_PATH,
+                "type": "http",
+                "resources": [{"names": ["replication"]}],
+            }
+        ]
+    else:
+        listeners = [
+            {
+                "port": MAIN_PROCESS_REPLICATION_PORT,
+                "bind_address": MAIN_PROCESS_LOCALHOST_ADDRESS,
+                "type": "http",
+                "resources": [{"names": ["replication"]}],
+            }
+        ]
    with open(config_path) as file_stream:
        original_config = yaml.safe_load(file_stream)
        original_listeners = original_config.get("listeners")
@@ -768,7 +793,17 @@ def generate_worker_files(

    # A list of internal endpoints to healthcheck, starting with the main process
    # which exists even if no workers do.
-    healthcheck_urls = ["http://localhost:8080/health"]
+    # This list ends up being part of the command line to curl, (curl added support for
+    # Unix sockets in version 7.40).
+    if using_unix_sockets:
+        healthcheck_urls = [
+            f"--unix-socket {MAIN_PROCESS_UNIX_SOCKET_PUBLIC_PATH} "
+            # The scheme and hostname from the following URL are ignored.
+            # The only thing that matters is the path `/health`
+            "http://localhost/health"
+        ]
+    else:
+        healthcheck_urls = ["http://localhost:8080/health"]

    # Get the set of all worker types that we have configured
    all_worker_types_in_use = set(chain(*requested_worker_types.values()))
@@ -805,8 +840,12 @@ def generate_worker_files(
        # given worker_type needs to stay assigned and not be replaced.
        worker_config["shared_extra_conf"].update(shared_config)
        shared_config = worker_config["shared_extra_conf"]
-
-        healthcheck_urls.append("http://localhost:%d/health" % (worker_port,))
+        if using_unix_sockets:
+            healthcheck_urls.append(
+                f"--unix-socket /run/worker.{worker_port} http://localhost/health"
+            )
+        else:
+            healthcheck_urls.append("http://localhost:%d/health" % (worker_port,))

        # Update the shared config with sharding-related options if necessary
        add_worker_roles_to_shared_config(
@@ -822,9 +861,10 @@ def generate_worker_files(
        # Then a worker config file
        convert(
            "/conf/worker.yaml.j2",
-            "/conf/workers/{name}.yaml".format(name=worker_name),
+            f"/conf/workers/{worker_name}.yaml",
            **worker_config,
            worker_log_config_filepath=log_config_filepath,
+            using_unix_sockets=using_unix_sockets,
        )

        # Save this worker's port number to the correct nginx upstreams
@@ -845,8 +885,13 @@ def generate_worker_files(
    nginx_upstream_config = ""
    for upstream_worker_base_name, upstream_worker_ports in nginx_upstreams.items():
        body = ""
-        for port in upstream_worker_ports:
-            body += f"    server localhost:{port};\n"
+        if using_unix_sockets:
+            for port in upstream_worker_ports:
+                body += f"    server unix:/run/worker.{port};\n"
+
+        else:
+            for port in upstream_worker_ports:
+                body += f"    server localhost:{port};\n"

        # Add to the list of configured upstreams
        nginx_upstream_config += NGINX_UPSTREAM_CONFIG_BLOCK.format(
@@ -876,10 +921,15 @@ def generate_worker_files(
    # If there are workers, add the main process to the instance_map too.
    if workers_in_use:
        instance_map = shared_config.setdefault("instance_map", {})
-        instance_map[MAIN_PROCESS_INSTANCE_NAME] = {
-            "host": MAIN_PROCESS_LOCALHOST_ADDRESS,
-            "port": MAIN_PROCESS_REPLICATION_PORT,
-        }
+        if using_unix_sockets:
+            instance_map[MAIN_PROCESS_INSTANCE_NAME] = {
+                "path": MAIN_PROCESS_UNIX_SOCKET_PRIVATE_PATH,
+            }
+        else:
+            instance_map[MAIN_PROCESS_INSTANCE_NAME] = {
+                "host": MAIN_PROCESS_LOCALHOST_ADDRESS,
+                "port": MAIN_PROCESS_REPLICATION_PORT,
+            }

    # Shared homeserver config
    convert(
@@ -889,6 +939,7 @@ def generate_worker_files(
        appservice_registrations=appservice_registrations,
        enable_redis=workers_in_use,
        workers_in_use=workers_in_use,
+        using_unix_sockets=using_unix_sockets,
    )

    # Nginx config
@@ -899,6 +950,7 @@ def generate_worker_files(
        upstream_directives=nginx_upstream_config,
        tls_cert_path=os.environ.get("SYNAPSE_TLS_CERT"),
        tls_key_path=os.environ.get("SYNAPSE_TLS_KEY"),
+        using_unix_sockets=using_unix_sockets,
    )

    # Supervisord config
@@ -908,6 +960,7 @@ def generate_worker_files(
        "/etc/supervisor/supervisord.conf",
        main_config_path=config_path,
        enable_redis=workers_in_use,
+        using_unix_sockets=using_unix_sockets,
    )

    convert(
@@ -947,6 +1000,7 @@ def generate_worker_log_config(
    extra_log_template_args["SYNAPSE_LOG_SENSITIVE"] = environ.get(
        "SYNAPSE_LOG_SENSITIVE"
    )
+    extra_log_template_args["SYNAPSE_LOG_TESTING"] = environ.get("SYNAPSE_LOG_TESTING")

    # Render and write the file
    log_config_filepath = f"/conf/workers/{worker_name}.log.config"
@@ -10,7 +10,7 @@ ARG PYTHON_VERSION=3.9
 ###
 # We hardcode the use of Debian bullseye here because this could change upstream
 # and other Dockerfiles used for testing are expecting bullseye.
-FROM docker.io/python:${PYTHON_VERSION}-slim-bullseye
+FROM docker.io/library/python:${PYTHON_VERSION}-slim-bullseye

 # Install Rust and other dependencies (stolen from normal Dockerfile)
 # install the OS build deps
@@ -82,7 +82,7 @@ def generate_config_from_template(
                with open(filename) as handle:
                    value = handle.read()
            else:
-                log("Generating a random secret for {}".format(secret))
+                log(f"Generating a random secret for {secret}")
                value = codecs.encode(os.urandom(32), "hex").decode()
                with open(filename, "w") as handle:
                    handle.write(value)
@@ -97,6 +97,7 @@
    - [Cancellation](development/synapse_architecture/cancellation.md)
    - [Log Contexts](log_contexts.md)
    - [Replication](replication.md)
+    - [Streams](development/synapse_architecture/streams.md)
    - [TCP Replication](tcp_replication.md)
    - [Faster remote joins](development/synapse_architecture/faster_joins.md)
  - [Internal Documentation](development/internal_documentation/README.md)
@@ -419,7 +419,7 @@ The following query parameters are available:

 * `from` (required) - The token to start returning events from. This token can be obtained from a prev_batch
  or next_batch token returned by the /sync endpoint, or from an end token returned by a previous request to this endpoint.
-* `to` - The token to spot returning events at.
+* `to` - The token to stop returning events at.
 * `limit` - The maximum number of events to return. Defaults to `10`.
 * `filter` - A JSON RoomEventFilter to filter returned events with.
 * `dir` - The direction to return events from. Either `f` for forwards or `b` for backwards. Setting
@@ -146,6 +146,7 @@ Body parameters:
 - `admin` - **bool**, optional, defaults to `false`. Whether the user is a homeserver administrator,
  granting them access to the Admin API, among other things.
 - `deactivated` - **bool**, optional. If unspecified, deactivation state will be left unchanged.
+- `locked` - **bool**, optional. If unspecified, locked state will be left unchanged.

  Note: the `password` field must also be set if both of the following are true:
  - `deactivated` is set to `false` and the user was previously deactivated (you are reactivating this user)
@@ -242,6 +243,9 @@ The following parameters should be set in the URL:

 - `dir` - Direction of media order. Either `f` for forwards or `b` for backwards.
  Setting this value to `b` will reverse the above sort order. Defaults to `f`.
+- `not_user_type` - Exclude certain user types, such as bot users, from the request.
+   Can be provided multiple times. Possible values are `bot`, `support` or "empty string".
+   "empty string" here means to exclude users without a type.

 Caution. The database only has indexes on the columns `name` and `creation_ts`.
 This means that if a different sort order is used (`is_guest`, `admin`,
@@ -729,7 +733,8 @@ POST /_synapse/admin/v1/users/<user_id>/login

 An optional `valid_until_ms` field can be specified in the request body as an
 integer timestamp that specifies when the token should expire. By default tokens
-do not expire.
+do not expire. Note that this API does not allow a user to login as themselves
+(to create more tokens).

 A response body like the following is returned:

@@ -1180,7 +1185,7 @@ The following parameters should be set in the URL:
 - `user_id` - The fully qualified MXID: for example, `@user:server.com`. The user must
  be local.

-### Check username availability
+## Check username availability

 Checks to see if a username is available, and valid, for the server. See [the client-server 
 API](https://matrix.org/docs/spec/client_server/r0.6.0#get-matrix-client-r0-register-available)
@@ -1198,7 +1203,7 @@ GET /_synapse/admin/v1/username_available?username=$localpart
 The request and response format is the same as the
 [/_matrix/client/r0/register/available](https://matrix.org/docs/spec/client_server/r0.6.0#get-matrix-client-r0-register-available) API.

-### Find a user based on their ID in an auth provider
+## Find a user based on their ID in an auth provider

 The API is:

@@ -1237,7 +1242,7 @@ Returns a `404` HTTP status code if no user was found, with a response body like
 _Added in Synapse 1.68.0._


-### Find a user based on their Third Party ID (ThreePID or 3PID)
+## Find a user based on their Third Party ID (ThreePID or 3PID)

 The API is:

@@ -23,7 +23,7 @@ people building from source should ensure they can fetch recent versions of Rust
 (e.g. by using [rustup](https://rustup.rs/)).

 The oldest supported version of SQLite is the version
-[provided](https://packages.debian.org/buster/libsqlite3-0) by
+[provided](https://packages.debian.org/bullseye/libsqlite3-0) by
 [Debian oldstable](https://wiki.debian.org/DebianOldStable).

 Context
@@ -322,7 +322,7 @@ The following command will let you run the integration test with the most common
 configuration:

 ```sh
-$ docker run --rm -it -v /path/where/you/have/cloned/the/repository\:/src:ro -v /path/to/where/you/want/logs\:/logs matrixdotorg/sytest-synapse:buster
+$ docker run --rm -it -v /path/where/you/have/cloned/the/repository\:/src:ro -v /path/to/where/you/want/logs\:/logs matrixdotorg/sytest-synapse:focal
 ```
 (Note that the paths must be full paths! You could also write `$(realpath relative/path)` if needed.)

@@ -370,6 +370,7 @@ The above will run a monolithic (single-process) Synapse with SQLite as the data
    See the [worker documentation](../workers.md) for additional information on workers.
 - Passing `ASYNCIO_REACTOR=1` as an environment variable to use the Twisted asyncio reactor instead of the default one.
 - Passing `PODMAN=1` will use the [podman](https://podman.io/) container runtime, instead of docker.
+- Passing `UNIX_SOCKETS=1` will utilise Unix socket functionality for Synapse, Redis, and Postgres(when applicable).

 To increase the log level for the tests, set `SYNAPSE_TEST_LOG_LEVEL`, e.g:
 ```sh
@@ -6,7 +6,7 @@ This is a work-in-progress set of notes with two goals:

 See also [MSC3902](https://github.com/matrix-org/matrix-spec-proposals/pull/3902).

-The key idea is described by [MSC706](https://github.com/matrix-org/matrix-spec-proposals/pull/3902). This allows servers to
+The key idea is described by [MSC3706](https://github.com/matrix-org/matrix-spec-proposals/pull/3706). This allows servers to
 request a lightweight response to the federation `/send_join` endpoint.
 This is called a **faster join**, also known as a **partial join**. In these
 notes we'll usually use the word "partial" as it matches the database schema.
@@ -0,0 +1,157 @@
+## Streams
+
+Synapse has a concept of "streams", which are roughly described in [`id_generators.py`](
+    https://github.com/matrix-org/synapse/blob/develop/synapse/storage/util/id_generators.py
+).
+Generally speaking, streams are a series of notifications that something in Synapse's database has changed that the application might need to respond to.
+For example:
+
+- The events stream reports new events (PDUs) that Synapse creates, or that Synapse accepts from another homeserver.
+- The account data stream reports changes to users' [account data](https://spec.matrix.org/v1.7/client-server-api/#client-config).
+- The to-device stream reports when a device has a new [to-device message](https://spec.matrix.org/v1.7/client-server-api/#send-to-device-messaging).
+
+See [`synapse.replication.tcp.streams`](
+    https://github.com/matrix-org/synapse/blob/develop/synapse/replication/tcp/streams/__init__.py
+) for the full list of streams.
+
+It is very helpful to understand the streams mechanism when working on any part of Synapse that needs to respond to changes—especially if those changes are made by different workers.
+To that end, let's describe streams formally, paraphrasing from the docstring of [`AbstractStreamIdGenerator`](
+    https://github.com/matrix-org/synapse/blob/a719b703d9bd0dade2565ddcad0e2f3a7a9d4c37/synapse/storage/util/id_generators.py#L96
+).
+
+### Definition
+
+A stream is an append-only log `T1, T2, ..., Tn, ...` of facts[^1] which grows over time.
+Only "writers" can add facts to a stream, and there may be multiple writers.
+
+Each fact has an ID, called its "stream ID".
+Readers should only process facts in ascending stream ID order.
+
+Roughly speaking, each stream is backed by a database table.
+It should have a `stream_id` (or similar) bigint column holding stream IDs, plus additional columns as necessary to describe the fact.
+Typically, a fact is expressed with a single row in its backing table.[^2]
+Within a stream, no two facts may have the same stream_id.
+
+> _Aside_. Some additional notes on streams' backing tables.
+>
+> 1. Rich would like to [ditch the backing tables](https://github.com/matrix-org/synapse/issues/13456).
+> 2. The backing tables may have other uses.
+     >    For example, the events table serves backs the events stream, and is read when processing new events.
+     >    But old rows are read from the table all the time, whenever Synapse needs to lookup some facts about an event.
+> 3. Rich suspects that sometimes the stream is backed by multiple tables, so the stream proper is the union of those tables.
+
+Stream writers can "reserve" a stream ID, and then later mark it as having being completed.
+Stream writers need to track the completion of each stream fact.
+In the happy case, completion means a fact has been written to the stream table.
+But unhappy cases (e.g. transaction rollback due to an error) also count as completion.
+Once completed, the rows written with that stream ID are fixed, and no new rows
+will be inserted with that ID.
+
+### Current stream ID
+
+For any given stream reader (including writers themselves), we may define a per-writer current stream ID:
+
+> The current stream ID _for a writer W_ is the largest stream ID such that
+> all transactions added by W with equal or smaller ID have completed.
+
+Similarly, there is a "linear" notion of current stream ID:
+
+> The "linear" current stream ID is the largest stream ID such that
+> all facts (added by any writer) with equal or smaller ID have completed.
+
+Because different stream readers A and B learn about new facts at different times, A and B may disagree about current stream IDs.
+Put differently: we should think of stream readers as being independent of each other, proceeding through a stream of facts at different rates.
+
+**NB.** For both senses of "current", that if a writer opens a transaction that never completes, the current stream ID will never advance beyond that writer's last written stream ID.
+
+For single-writer streams, the per-writer current ID and the linear current ID are the same.
+Both senses of current ID are monotonic, but they may "skip" or jump over IDs because facts complete out of order.
+
+
+_Example_.
+Consider a single-writer stream which is initially at ID 1.
+
+| Action     | Current stream ID | Notes                                           |
+|------------|-------------------|-------------------------------------------------|
+|            | 1                 |                                                 |
+| Reserve 2  | 1                 |                                                 |
+| Reserve 3  | 1                 |                                                 |
+| Complete 3 | 1                 | current ID unchanged, waiting for 2 to complete |
+| Complete 2 | 3                 | current ID jumps from 1 -> 3                    |
+| Reserve 4  | 3                 |                                                 |
+| Reserve 5  | 3                 |                                                 |
+| Reserve 6  | 3                 |                                                 |
+| Complete 5 | 3                 |                                                 |
+| Complete 4 | 5                 | current ID jumps 3->5, even though 6 is pending |
+| Complete 6 | 6                 |                                                 |
+
+
+### Multi-writer streams
+
+There are two ways to view a multi-writer stream.
+
+1. Treat it as a collection of distinct single-writer streams, one
+   for each writer.
+2. Treat it as a single stream.
+
+The single stream (option 2) is conceptually simpler, and easier to represent (a single stream id).
+However, it requires each reader to know about the entire set of writers, to ensures that readers don't erroneously advance their current stream position too early and miss a fact from an unknown writer.
+In contrast, multiple parallel streams (option 1) are more complex, requiring more state to represent (map from writer to stream id).
+The payoff for doing so is that readers can "peek" ahead to facts that completed on one writer no matter the state of the others, reducing latency.
+
+Note that a multi-writer stream can be viewed in both ways.
+For example, the events stream is treated as multiple single-writer streams (option 1) by the sync handler, so that events are sent to clients as soon as possible.
+But the background process that works through events treats them as a single linear stream.
+
+Another useful example is the cache invalidation stream.
+The facts this stream holds are instructions to "you should now invalidate these cache entries".
+We only ever treat this as a multiple single-writer streams as there is no important ordering between cache invalidations.
+(Invalidations are self-contained facts; and the invalidations commute/are idempotent).
+
+### Writing to streams
+
+Writers need to track:
+ - track their current position (i.e. its own per-writer stream ID).
+ - their facts currently awaiting completion.
+
+At startup, 
+ - the current position of that writer can be found by querying the database (which suggests that facts need to be written to the database atomically, in a transaction); and
+ - there are no facts awaiting completion.
+
+To reserve a stream ID, call [`nextval`](https://www.postgresql.org/docs/current/functions-sequence.html) on the appropriate postgres sequence.
+
+To write a fact to the stream: insert the appropriate rows to the appropriate backing table.
+
+To complete a fact, first remove it from your map of facts currently awaiting completion.
+Then, if no earlier fact is awaiting completion, the writer can advance its current position in that stream.
+Upon doing so it should emit an `RDATA` message[^3], once for every fact between the old and the new stream ID.
+
+### Subscribing to streams
+
+Readers need to track the current position of every writer.
+
+At startup, they can find this by contacting each writer with a `REPLICATE` message,
+requesting that all writers reply describing their current position in their streams.
+Writers reply with a `POSITION` message.
+
+To learn about new facts, readers should listen for `RDATA` messages and process them to respond to the new fact.
+The `RDATA` itself is not a self-contained representation of the fact;
+readers will have to query the stream tables for the full details.
+Readers must also advance their record of the writer's current position for that stream.
+
+# Summary
+
+In a nutshell: we have an append-only log with a "buffer/scratchpad" at the end where we have to wait for the sequence to be linear and contiguous.
+
+
+---
+
+[^1]: we use the word _fact_ here for two reasons.
+Firstly, the word "event" is already heavily overloaded (PDUs, EDUs, account data, ...) and we don't need to make that worse.
+Secondly, "fact" emphasises that the things we append to a stream cannot change after the fact.
+
+[^2]: A fact might be expressed with 0 rows, e.g. if we opened a transaction to persist an event, but failed and rolled the transaction back before marking the fact as completed.
+In principle a fact might be expressed with 2 or more rows; if so, each of those rows should share the fact's stream ID.
+
+[^3]: This communication used to happen directly with the writers [over TCP](../../tcp_replication.md);
+nowadays it's done via Redis's Pubsub.
@@ -348,6 +348,42 @@ callback returns `False`, Synapse falls through to the next one. The value of th
 callback that does not return `False` will be used. If this happens, Synapse will not call
 any of the subsequent implementations of this callback.

+
+### `check_login_for_spam`
+
+_First introduced in Synapse v1.87.0_
+
+```python
+async def check_login_for_spam(
+    user_id: str,
+    device_id: Optional[str],
+    initial_display_name: Optional[str],
+    request_info: Collection[Tuple[Optional[str], str]],
+    auth_provider_id: Optional[str] = None,
+) -> Union["synapse.module_api.NOT_SPAM", "synapse.module_api.errors.Codes"]
+```
+
+Called when a user logs in.
+
+The arguments passed to this callback are:
+
+* `user_id`: The user ID the user is logging in with
+* `device_id`: The device ID the user is re-logging into.
+* `initial_display_name`: The device display name, if any.
+* `request_info`: A collection of tuples, which first item is a user agent, and which
+  second item is an IP address. These user agents and IP addresses are the ones that were
+  used during the login process.
+* `auth_provider_id`: The identifier of the SSO authentication provider, if any.
+
+If multiple modules implement this callback, they will be considered in order. If a
+callback returns `synapse.module_api.NOT_SPAM`, Synapse falls through to the next one.
+The value of the first callback that does not return `synapse.module_api.NOT_SPAM` will
+be used. If this happens, Synapse will not call any of the subsequent implementations of
+this callback.
+
+*Note:* This will not be called when a user registers.
+
+
 ## Example

 The example below is a module that implements the spam checker callback
@@ -95,7 +95,7 @@ matrix.example.com {
 }

 example.com:8448 {
-  reverse_proxy localhost:8008
+  reverse_proxy /_matrix/* localhost:8008
 }
 ```

@@ -135,8 +135,8 @@ Unofficial package are built for SLES 15 in the openSUSE:Backports:SLE-15 reposi

 #### ArchLinux

-The quickest way to get up and running with ArchLinux is probably with the community package
-<https://archlinux.org/packages/community/x86_64/matrix-synapse/>, which should pull in most of
+The quickest way to get up and running with ArchLinux is probably with the package provided by ArchLinux
+<https://archlinux.org/packages/extra/x86_64/matrix-synapse/>, which should pull in most of
 the necessary dependencies.

 pip may be outdated (6.0.7-1 and needs to be upgraded to 6.0.8-1 ):
@@ -200,7 +200,7 @@ When following this route please make sure that the [Platform-specific prerequis
 System requirements:

 - POSIX-compliant system (tested on Linux & OS X)
- Python 3.7 or later, up to Python 3.11.
+- Python 3.8 or later, up to Python 3.11.
 - At least 1GB of free RAM if you want to join large public rooms like #matrix:matrix.org

 If building on an uncommon architecture for which pre-built wheels are
@@ -3,7 +3,7 @@
 A structured logging system can be useful when your logs are destined for a
 machine to parse and process. By maintaining its machine-readable characteristics,
 it enables more efficient searching and aggregations when consumed by software
-such as the "ELK stack".
+such as the [ELK stack](https://opensource.com/article/18/9/open-source-log-aggregation-tools).

 Synapse's structured logging system is configured via the file that Synapse's
 `log_config` config option points to. The file should include a formatter which
@@ -1,8 +1,4 @@
 worker_app: synapse.app.generic_worker
 worker_name: background_worker

-# The replication listener on the main synapse process.
-worker_replication_host: 127.0.0.1
-worker_replication_http_port: 9093
-
 worker_log_config: /etc/matrix-synapse/background-worker-log.yaml
@@ -1,9 +1,5 @@
 worker_app: synapse.app.generic_worker
-worker_name: event_persister1 
-
-# The replication listener on the main synapse process.
-worker_replication_host: 127.0.0.1
-worker_replication_http_port: 9093
+worker_name: event_persister1

 worker_listeners:
  - type: http
@@ -1,8 +1,4 @@
 worker_app: synapse.app.federation_sender
 worker_name: federation_sender1

-# The replication listener on the main synapse process.
-worker_replication_host: 127.0.0.1
-worker_replication_http_port: 9093
-
 worker_log_config: /etc/matrix-synapse/federation-sender-log.yaml
@@ -1,10 +1,6 @@
 worker_app: synapse.app.media_repository
 worker_name: media_worker

-# The replication listener on the main synapse process.
-worker_replication_host: 127.0.0.1
-worker_replication_http_port: 9093
-
 worker_listeners:
  - type: http
    port: 8085
@@ -1,8 +1,4 @@
 worker_app: synapse.app.pusher
 worker_name: pusher_worker1

-# The replication listener on the main synapse process.
-worker_replication_host: 127.0.0.1
-worker_replication_http_port: 9093
-
 worker_log_config: /etc/matrix-synapse/pusher-worker-log.yaml
@@ -88,6 +88,65 @@ process, for example:
    dpkg -i matrix-synapse-py3_1.3.0+stretch1_amd64.deb
    ```

+# Upgrading to v1.90.0
+
+## App service query parameter authorization is now a configuration option
+
+Synapse v1.81.0 deprecated application service authorization via query parameters as this is
+considered insecure - and from Synapse v1.71.0 forwards the application service token has also been sent via 
+[the `Authorization` header](https://spec.matrix.org/v1.6/application-service-api/#authorization)], making the insecure
+query parameter authorization redundant. Since removing the ability to continue to use query parameters could break 
+backwards compatibility it has now been put behind a configuration option, `use_appservice_legacy_authorization`.  
+This option defaults to false, but can be activated by adding 
+```yaml
+use_appservice_legacy_authorization: true 
+```
+to your configuration.
+
+# Upgrading to v1.89.0
+
+## Removal of unspecced `user` property for `/register`
+
+Application services can no longer call `/register` with a `user` property to create new users.
+The standard `username` property should be used instead. See the
+[Application Service specification](https://spec.matrix.org/v1.7/application-service-api/#server-admin-style-permissions)
+for more information.
+
+# Upgrading to v1.88.0
+
+## Minimum supported Python version
+
+The minimum supported Python version has been increased from v3.7 to v3.8.
+You will need Python 3.8 to run Synapse v1.88.0 (due out July 18th, 2023).
+
+If you use current versions of the Matrix.org-distributed Debian
+packages or Docker images, no action is required.
+
+## Removal of `worker_replication_*` settings
+
+As mentioned previously in [Upgrading to v1.84.0](#upgrading-to-v1840), the following deprecated settings
+are being removed in this release of Synapse:
+
+* [`worker_replication_host`](https://matrix-org.github.io/synapse/v1.86/usage/configuration/config_documentation.html#worker_replication_host)
+* [`worker_replication_http_port`](https://matrix-org.github.io/synapse/v1.86/usage/configuration/config_documentation.html#worker_replication_http_port)
+* [`worker_replication_http_tls`](https://matrix-org.github.io/synapse/v1.86/usage/configuration/config_documentation.html#worker_replication_http_tls)
+
+Please ensure that you have migrated to using `main` on your shared configuration's `instance_map`
+(or create one if necessary). This is required if you have ***any*** workers at all;
+administrators of single-process (monolith) installations don't need to do anything.
+
+For an illustrative example, please see [Upgrading to v1.84.0](#upgrading-to-v1840) below.
+
+
+# Upgrading to v1.86.0
+
+## Minimum supported Rust version
+
+The minimum supported Rust version has been increased from v1.58.1 to v1.60.0.
+Users building from source will need to ensure their `rustc` version is up to
+date.
+
+
 # Upgrading to v1.85.0

 ## Application service registration with "user" property deprecation
@@ -27,9 +27,8 @@ What servers are currently participating in this room?
 Run this sql query on your db:
 ```sql
 SELECT DISTINCT split_part(state_key, ':', 2)
-    FROM current_state_events AS c
-    INNER JOIN room_memberships AS m USING (room_id, event_id)
-    WHERE room_id = '!cURbafjkfsMDVwdRDQ:matrix.org' AND membership = 'join';
+FROM current_state_events
+WHERE room_id = '!cURbafjkfsMDVwdRDQ:matrix.org' AND membership = 'join';
 ```

 What users are registered on my server?
@@ -462,6 +462,20 @@ See the docs [request log format](../administration/request_log.md).
 * `additional_resources`: Only valid for an 'http' listener. A map of
   additional endpoints which should be loaded via dynamic modules.

+Unix socket support (_Added in Synapse 1.89.0_):
+* `path`: A path and filename for a Unix socket. Make sure it is located in a
+  directory with read and write permissions, and that it already exists (the directory
+  will not be created). Defaults to `None`.
+  * **Note**: The use of both `path` and `port` options for the same `listener` is not
+    compatible.
+  * The `x_forwarded` option defaults to true  when using Unix sockets and can be omitted.
+  * Other options that would not make sense to use with a UNIX socket, such as 
+    `bind_addresses` and `tls` will be ignored and can be removed.
+* `mode`: The file permissions to set on the UNIX socket. Defaults to `666`
+* **Note:** Must be set as `type: http` (does not support `metrics` and `manhole`). 
+  Also make sure that `metrics` is not included in `resources` -> `names`
+
+
 Valid resource names are:

 * `client`: the client-server API (/_matrix/client), and the synapse admin API (/_synapse/admin). Also implies `media` and `static`.
@@ -474,7 +488,7 @@ Valid resource names are:

 * `media`: the media API (/_matrix/media).

-* `metrics`: the metrics interface. See [here](../../metrics-howto.md).
+* `metrics`: the metrics interface. See [here](../../metrics-howto.md). (Not compatible with Unix sockets)

 * `openid`: OpenID authentication. See [here](../../openid.md).

@@ -533,6 +547,22 @@ listeners:
    bind_addresses: ['::1', '127.0.0.1']
    type: manhole
 ```
+Example configuration #3:
+```yaml
+listeners:
+  # Unix socket listener: Ideal for Synapse deployments behind a reverse proxy, offering
+  # lightweight interprocess communication without TCP/IP overhead, avoid port
+  # conflicts, and providing enhanced security through system file permissions.
+  #
+  # Note that x_forwarded will default to true, when using a UNIX socket. Please see
+  # https://matrix-org.github.io/synapse/latest/reverse_proxy.html.
+  #
+  - path: /var/run/synapse/main_public.sock
+    type: http
+    resources:
+      - names: [client, federation]
+```
+
 ---
 ### `manhole_settings`

@@ -1196,6 +1226,43 @@ Example configuration:
 allow_device_name_lookup_over_federation: true
 ```
 ---
+### `federation`
+
+The federation section defines some sub-options related to federation.
+
+The following options are related to configuring timeout and retry logic for one request,
+independently of the others.
+Short retry algorithm is used when something or someone will wait for the request to have an
+answer, while long retry is used for requests that happen in the background,
+like sending a federation transaction.
+
+* `client_timeout`: timeout for the federation requests. Default to 60s.
+* `max_short_retry_delay`: maximum delay to be used for the short retry algo. Default to 2s.
+* `max_long_retry_delay`: maximum delay to be used for the short retry algo. Default to 60s.
+* `max_short_retries`: maximum number of retries for the short retry algo. Default to 3 attempts.
+* `max_long_retries`: maximum number of retries for the long retry algo. Default to 10 attempts.
+
+The following options control the retry logic when communicating with a specific homeserver destination.
+Unlike the previous configuration options, these values apply across all requests
+for a given destination and the state of the backoff is stored in the database.
+
+* `destination_min_retry_interval`: the initial backoff, after the first request fails. Defaults to 10m.
+* `destination_retry_multiplier`: how much we multiply the backoff by after each subsequent fail. Defaults to 2.
+* `destination_max_retry_interval`: a cap on the backoff. Defaults to a week.
+
+Example configuration:
+```yaml
+federation:
+  client_timeout: 180s
+  max_short_retry_delay: 7s
+  max_long_retry_delay: 100s
+  max_short_retries: 5
+  max_long_retries: 20
+  destination_min_retry_interval: 30s
+  destination_retry_multiplier: 5
+  destination_max_retry_interval: 12h
+```
+---
 ## Caching

 Options related to caching.
@@ -2570,7 +2637,50 @@ Example configuration:
 ```yaml
 nonrefreshable_access_token_lifetime: 24h
 ```
+---
+### `ui_auth`

+The amount of time to allow a user-interactive authentication session to be active.
+
+This defaults to 0, meaning the user is queried for their credentials
+before every action, but this can be overridden to allow a single
+validation to be re-used.  This weakens the protections afforded by
+the user-interactive authentication process, by allowing for multiple
+(and potentially different) operations to use the same validation session.
+
+This is ignored for potentially "dangerous" operations (including
+deactivating an account, modifying an account password, adding a 3PID,
+and minting additional login tokens).
+
+Use the `session_timeout` sub-option here to change the time allowed for credential validation.
+
+Example configuration:
+```yaml
+ui_auth:
+    session_timeout: "15s"
+```
+---
+### `login_via_existing_session`
+
+Matrix supports the ability of an existing session to mint a login token for
+another client.
+
+Synapse disables this by default as it has security ramifications -- a malicious
+client could use the mechanism to spawn more than one session.
+
+The duration of time the generated token is valid for can be configured with the
+`token_timeout` sub-option.
+
+User-interactive authentication is required when this is enabled unless the
+`require_ui_auth` sub-option is set to `False`.
+
+Example configuration:
+```yaml
+login_via_existing_session:
+    enabled: true
+    require_ui_auth: false
+    token_timeout: "5m"
+```
 ---
 ## Metrics
 Config options related to metrics.
@@ -2738,6 +2848,20 @@ Example configuration:
 ```yaml
 track_appservice_user_ips: true
 ```
+---
+### `use_appservice_legacy_authorization`
+
+Whether to send the application service access tokens via the `access_token` query parameter
+per older versions of the Matrix specification. Defaults to false. Set to true to enable sending
+access tokens via a query parameter.
+
+**Enabling this option is considered insecure and is not recommended. **
+
+Example configuration:
+```yaml
+use_appservice_legacy_authorization: true 
+```
+
 ---
 ### `macaroon_secret_key`

@@ -2901,6 +3025,16 @@ enable SAML login. You can either put your entire pysaml config inline using the
 option, or you can specify a path to a psyaml config file with the sub-option `config_path`.
 This setting has the following sub-options:

+* `idp_name`: A user-facing name for this identity provider, which is used to
+   offer the user a choice of login mechanisms.
+* `idp_icon`: An optional icon for this identity provider, which is presented
+   by clients and Synapse's own IdP picker page. If given, must be an
+   MXC URI of the format `mxc://<server-name>/<media-id>`. (An easy way to
+   obtain such an MXC URI is to upload an image to an (unencrypted) room
+   and then copy the "url" from the source of the event.)
+* `idp_brand`: An optional brand for this identity provider, allowing clients
+   to style the login flow according to the identity provider in question.
+   See the [spec](https://spec.matrix.org/latest/) for possible options here.
 * `sp_config`: the configuration for the pysaml2 Service Provider. See pysaml2 docs for format of config.
   Default values will be used for the `entityid` and `service` settings,
   so it is not normally necessary to specify them unless you need to
@@ -3052,7 +3186,7 @@ Options for each entry include:

 * `idp_icon`: An optional icon for this identity provider, which is presented
   by clients and Synapse's own IdP picker page. If given, must be an
-   MXC URI of the format mxc://<server-name>/<media-id>. (An easy way to
+   MXC URI of the format `mxc://<server-name>/<media-id>`. (An easy way to
   obtain such an MXC URI is to upload an image to an (unencrypted) room
   and then copy the "url" from the source of the event.)

@@ -3267,6 +3401,16 @@ Enable Central Authentication Service (CAS) for registration and login.
 Has the following sub-options:
 * `enabled`: Set this to true to enable authorization against a CAS server.
   Defaults to false.
+* `idp_name`: A user-facing name for this identity provider, which is used to
+   offer the user a choice of login mechanisms.
+* `idp_icon`: An optional icon for this identity provider, which is presented
+   by clients and Synapse's own IdP picker page. If given, must be an
+   MXC URI of the format `mxc://<server-name>/<media-id>`. (An easy way to
+   obtain such an MXC URI is to upload an image to an (unencrypted) room
+   and then copy the "url" from the source of the event.)
+* `idp_brand`: An optional brand for this identity provider, allowing clients
+   to style the login flow according to the identity provider in question.
+   See the [spec](https://spec.matrix.org/latest/) for possible options here.
 * `server_url`: The URL of the CAS authorization endpoint.
 * `displayname_attribute`: The attribute of the CAS response to use as the display name.
   If no name is given here, no displayname will be set.
@@ -3415,28 +3559,6 @@ password_config:
      require_uppercase: true
 ```
 ---
-### `ui_auth`
-
-The amount of time to allow a user-interactive authentication session to be active.
-
-This defaults to 0, meaning the user is queried for their credentials
-before every action, but this can be overridden to allow a single
-validation to be re-used.  This weakens the protections afforded by
-the user-interactive authentication process, by allowing for multiple
-(and potentially different) operations to use the same validation session.
-
-This is ignored for potentially "dangerous" operations (including
-deactivating an account, modifying an account password, and
-adding a 3PID).
-
-Use the `session_timeout` sub-option here to change the time allowed for credential validation.
-
-Example configuration:
-```yaml
-ui_auth:
-    session_timeout: "15s"
-```
---
 ## Push
 Configuration settings related to push notifications

@@ -3529,6 +3651,7 @@ This option has the following sub-options:
 * `prefer_local_users`: Defines whether to prefer local users in search query results.
   If set to true, local users are more likely to appear above remote users when searching the
   user directory. Defaults to false.
+* `show_locked_users`: Defines whether to show locked users in search query results. Defaults to false.

 Example configuration:
 ```yaml
@@ -3536,6 +3659,7 @@ user_directory:
    enabled: false
    search_all_users: true
    prefer_local_users: true
+    show_locked_users: true
 ```
 ---
 ### `user_consent`
@@ -3883,13 +4007,14 @@ federation_sender_instances:
 ---
 ### `instance_map`

-When using workers this should be a map from [`worker_name`](#worker_name) to the
-HTTP replication listener of the worker, if configured, and to the main process.
-Each worker declared under [`stream_writers`](../../workers.md#stream-writers) needs
-a HTTP replication listener, and that listener should be included in the `instance_map`.
-The main process also needs an entry on the `instance_map`, and it should be listed under
-`main` **if even one other worker exists**. Ensure the port matches with what is declared 
-inside the `listener` block for a `replication` listener.
+When using workers this should be a map from [`worker_name`](#worker_name) to the HTTP
+replication listener of the worker, if configured, and to the main process. Each worker
+declared under [`stream_writers`](../../workers.md#stream-writers) and
+[`outbound_federation_restricted_to`](#outbound_federation_restricted_to) needs a HTTP
+replication listener, and that listener should be included in the `instance_map`. The
+main process also needs an entry on the `instance_map`, and it should be listed under
+`main` **if even one other worker exists**. Ensure the port matches with what is
+declared inside the `listener` block for a `replication` listener.


 Example configuration:
@@ -3902,6 +4027,14 @@ instance_map:
    host: localhost
    port: 8034
 ```
+Example configuration(#2, for UNIX sockets):
+```yaml
+instance_map:
+  main:
+    path: /var/run/synapse/main_replication.sock
+  worker1:
+    path: /var/run/synapse/worker1_replication.sock
+```
 ---
 ### `stream_writers`

@@ -3919,6 +4052,24 @@ stream_writers:
  typing: worker1
 ```
 ---
+### `outbound_federation_restricted_to`
+
+When using workers, you can restrict outbound federation traffic to only go through a
+specific subset of workers. Any worker specified here must also be in the
+[`instance_map`](#instance_map).
+[`worker_replication_secret`](#worker_replication_secret) must also be configured to
+authorize inter-worker communication.
+
+```yaml
+outbound_federation_restricted_to:
+  - federation_sender1
+  - federation_sender2
+```
+
+Also see the [worker
+documentation](../../workers.md#restrict-outbound-federation-traffic-to-a-specific-set-of-workers)
+for more info.
+---
 ### `run_background_tasks_on`

 The [worker](../../workers.md#background-tasks) that is used to run
@@ -4043,51 +4194,6 @@ Example configuration:
 worker_name: generic_worker1
 ```
 ---
-### `worker_replication_host`
-*Deprecated as of version 1.84.0. Place `host` under `main` entry on the [`instance_map`](#instance_map) in your shared yaml configuration instead.*
-
-The HTTP replication endpoint that it should talk to on the main Synapse process.
-The main Synapse process defines this with a `replication` resource in
-[`listeners` option](#listeners).
-
-Example configuration:
-```yaml
-worker_replication_host: 127.0.0.1
-```
---
-### `worker_replication_http_port`
-*Deprecated as of version 1.84.0. Place `port` under `main` entry on the [`instance_map`](#instance_map) in your shared yaml configuration instead.*
-
-The HTTP replication port that it should talk to on the main Synapse process.
-The main Synapse process defines this with a `replication` resource in
-[`listeners` option](#listeners).
-
-Example configuration:
-```yaml
-worker_replication_http_port: 9093
-```
---
-### `worker_replication_http_tls`
-*Deprecated as of version 1.84.0. Place `tls` under `main` entry on the [`instance_map`](#instance_map) in your shared yaml configuration instead.*
-
-Whether TLS should be used for talking to the HTTP replication port on the main
-Synapse process.
-The main Synapse process defines this with the `tls` option on its [listener](#listeners) that
-has the `replication` resource enabled.
-
-**Please note:** by default, it is not safe to expose replication ports to the
-public Internet, even with TLS enabled.
-See [`worker_replication_secret`](#worker_replication_secret).
-
-Defaults to `false`.
-
-*Added in Synapse 1.72.0.*
-
-Example configuration:
-```yaml
-worker_replication_http_tls: true
-```
---
 ### `worker_listeners`

 A worker can handle HTTP requests. To do so, a `worker_listeners` option
@@ -4106,6 +4212,18 @@ worker_listeners:
    resources:
      - names: [client, federation]
 ```
+Example configuration(#2, using UNIX sockets with a `replication` listener):
+```yaml
+worker_listeners:
+  - type: http
+    path: /var/run/synapse/worker_public.sock
+    resources:
+      - names: [client, federation]
+  - type: http
+    path: /var/run/synapse/worker_replication.sock
+    resources:
+      - names: [replication]
+```
 ---
 ### `worker_manhole`

@@ -95,9 +95,12 @@ for the main process
 * Secondly, you need to enable
 [redis-based replication](usage/configuration/config_documentation.md#redis)
 * You will need to add an [`instance_map`](usage/configuration/config_documentation.md#instance_map) 
-with the `main` process defined, as well as the relevant connection information from 
-it's HTTP `replication` listener (defined in step 1 above). Note that the `host` defined 
-is the address the worker needs to look for the `main` process at, not necessarily the same address that is bound to.
+with the `main` process defined, as well as the relevant connection information from
+it's HTTP `replication` listener (defined in step 1 above).
+  * Note that the `host` defined is the address the worker needs to look for the `main`
+  process at, not necessarily the same address that is bound to.
+  * If you are using Unix sockets for the `replication` resource, make sure to
+  use a `path` to the socket file instead of a `port`.
 * Optionally, a [shared secret](usage/configuration/config_documentation.md#worker_replication_secret)
 can be used to authenticate HTTP traffic between workers. For example:

@@ -145,9 +148,6 @@ In the config file for each worker, you must specify:
   with an `http` listener.
 * **Synapse 1.72 and older:** if handling the `^/_matrix/client/v3/keys/upload` endpoint, the HTTP URI for
   the main process (`worker_main_http_uri`). This config option is no longer required and is ignored when running Synapse 1.73 and newer.
- * **Synapse 1.83 and older:** The HTTP replication endpoint that the worker should talk to on the main synapse process
-   ([`worker_replication_host`](usage/configuration/config_documentation.md#worker_replication_host) and
-   [`worker_replication_http_port`](usage/configuration/config_documentation.md#worker_replication_http_port)). If using Synapse 1.84 and newer, these are not needed if `main` is defined on the [shared configuration](#shared-configuration) `instance_map`

 For example:

@@ -177,11 +177,11 @@ The following applies to Synapse installations that have been installed from sou

 You can start the main Synapse process with Poetry by running the following command:
 ```console
-poetry run synapse_homeserver -c [your homeserver.yaml]
+poetry run synapse_homeserver --config-file [your homeserver.yaml]
 ```
 For worker setups, you can run the following command
 ```console
-poetry run synapse_worker -c [your worker.yaml]
+poetry run synapse_worker --config-file [your homeserver.yaml] --config-file [your worker.yaml]
 ```
 ## Available worker applications

@@ -232,7 +232,6 @@ information.
    ^/_matrix/client/v1/rooms/.*/hierarchy$
    ^/_matrix/client/(v1|unstable)/rooms/.*/relations/
    ^/_matrix/client/v1/rooms/.*/threads$
-    ^/_matrix/client/unstable/org.matrix.msc2716/rooms/.*/batch_send$
    ^/_matrix/client/unstable/im.nheko.summary/rooms/.*/summary$
    ^/_matrix/client/(r0|v3|unstable)/account/3pid$
    ^/_matrix/client/(r0|v3|unstable)/account/whoami$
@@ -532,6 +531,30 @@ the stream writer for the `presence` stream:

    ^/_matrix/client/(api/v1|r0|v3|unstable)/presence/

+#### Restrict outbound federation traffic to a specific set of workers
+
+The
+[`outbound_federation_restricted_to`](usage/configuration/config_documentation.md#outbound_federation_restricted_to)
+configuration is useful to make sure outbound federation traffic only goes through a
+specified subset of workers. This allows you to set more strict access controls (like a
+firewall) for all workers and only allow the `federation_sender`'s to contact the
+outside world.
+
+```yaml
+instance_map:
+    main:
+        host: localhost
+        port: 8030
+    federation_sender1:
+        host: localhost
+        port: 8034
+
+outbound_federation_restricted_to:
+  - federation_sender1
+
+worker_replication_secret: "secret_secret"
+```
+
 #### Background tasks

 There is also support for moving background tasks to a separate
@@ -8,11 +8,11 @@
        "pre-commit-hooks": "pre-commit-hooks"
      },
      "locked": {
-        "lastModified": 1683102061,
-        "narHash": "sha256-kOphT6V0uQUlFNBP3GBjs7DAU7fyZGGqCs9ue1gNY6E=",
+        "lastModified": 1690534632,
+        "narHash": "sha256-kOXS9x5y17VKliC7wZxyszAYrWdRl1JzggbQl0gyo94=",
        "owner": "cachix",
        "repo": "devenv",
-        "rev": "ff1f29e41756553174d596cafe3a9fa77595100b",
+        "rev": "6568e7e485a46bbf32051e4d6347fa1fed8b2f25",
        "type": "github"
      },
      "original": {
@@ -22,27 +22,6 @@
        "type": "github"
      }
    },
-    "fenix": {
-      "inputs": {
-        "nixpkgs": [
-          "nixpkgs"
-        ],
-        "rust-analyzer-src": "rust-analyzer-src"
-      },
-      "locked": {
-        "lastModified": 1682490133,
-        "narHash": "sha256-tR2Qx0uuk97WySpSSk4rGS/oH7xb5LykbjATcw1vw1I=",
-        "owner": "nix-community",
-        "repo": "fenix",
-        "rev": "4e9412753ab75ef0e038a5fe54a062fb44c27c6a",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-community",
-        "repo": "fenix",
-        "type": "github"
-      }
-    },
    "flake-compat": {
      "flake": false,
      "locked": {
@@ -60,12 +39,33 @@
      }
    },
    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
      "locked": {
-        "lastModified": 1667395993,
-        "narHash": "sha256-nuEHfE/LcWyuSWnS8t12N1wc105Qtau+/OdUAjtQ0rA=",
+        "lastModified": 1685518550,
+        "narHash": "sha256-o2d0KcvaXzTrPRIo0kOLV0/QXHhDQ5DTi+OxcjO8xqY=",
        "owner": "numtide",
        "repo": "flake-utils",
-        "rev": "5aed5285a952e0b949eb3ba02c12fa4fcfef535f",
+        "rev": "a1720a10a6cfe8234c0e93907ffe81be440f4cef",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_2": {
+      "inputs": {
+        "systems": "systems_2"
+      },
+      "locked": {
+        "lastModified": 1681202837,
+        "narHash": "sha256-H+Rh19JDwRtpVPAWp64F+rlEtxUWBAQW28eAi3SRSzg=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "cfacdce06f30d2b68473a46042957675eebb3401",
        "type": "github"
      },
      "original": {
@@ -170,27 +170,27 @@
    },
    "nixpkgs-stable": {
      "locked": {
-        "lastModified": 1673800717,
-        "narHash": "sha256-SFHraUqLSu5cC6IxTprex/nTsI81ZQAtDvlBvGDWfnA=",
+        "lastModified": 1685801374,
+        "narHash": "sha256-otaSUoFEMM+LjBI1XL/xGB5ao6IwnZOXc47qhIgJe8U=",
        "owner": "NixOS",
        "repo": "nixpkgs",
-        "rev": "2f9fd351ec37f5d479556cd48be4ca340da59b8f",
+        "rev": "c37ca420157f4abc31e26f436c1145f8951ff373",
        "type": "github"
      },
      "original": {
        "owner": "NixOS",
-        "ref": "nixos-22.11",
+        "ref": "nixos-23.05",
        "repo": "nixpkgs",
        "type": "github"
      }
    },
    "nixpkgs_2": {
      "locked": {
-        "lastModified": 1682519441,
-        "narHash": "sha256-Vsq/8NOtvW1AoC6shCBxRxZyMQ+LhvPuJT6ltbzuv+Y=",
+        "lastModified": 1690535733,
+        "narHash": "sha256-WgjUPscQOw3cB8yySDGlyzo6cZNihnRzUwE9kadv/5I=",
        "owner": "NixOS",
        "repo": "nixpkgs",
-        "rev": "7a32a141db568abde9bc389845949dc2a454dfd3",
+        "rev": "8cacc05fbfffeaab910e8c2c9e2a7c6b32ce881a",
        "type": "github"
      },
      "original": {
@@ -200,6 +200,22 @@
        "type": "github"
      }
    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1681358109,
+        "narHash": "sha256-eKyxW4OohHQx9Urxi7TQlFBTDWII+F+x2hklDOQPB50=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "96ba1c52e54e74c3197f4d43026b3f3d92e83ff9",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
    "pre-commit-hooks": {
      "inputs": {
        "flake-compat": [
@@ -215,11 +231,11 @@
        "nixpkgs-stable": "nixpkgs-stable"
      },
      "locked": {
-        "lastModified": 1678376203,
-        "narHash": "sha256-3tyYGyC8h7fBwncLZy5nCUjTJPrHbmNwp47LlNLOHSM=",
+        "lastModified": 1688056373,
+        "narHash": "sha256-2+SDlNRTKsgo3LBRiMUcoEUb6sDViRNQhzJquZ4koOI=",
        "owner": "cachix",
        "repo": "pre-commit-hooks.nix",
-        "rev": "1a20b9708962096ec2481eeb2ddca29ed747770a",
+        "rev": "5843cf069272d92b60c3ed9e55b7a8989c01d4c7",
        "type": "github"
      },
      "original": {
@@ -231,25 +247,27 @@
    "root": {
      "inputs": {
        "devenv": "devenv",
-        "fenix": "fenix",
        "nixpkgs": "nixpkgs_2",
-        "systems": "systems"
+        "rust-overlay": "rust-overlay",
+        "systems": "systems_3"
      }
    },
-    "rust-analyzer-src": {
-      "flake": false,
+    "rust-overlay": {
+      "inputs": {
+        "flake-utils": "flake-utils_2",
+        "nixpkgs": "nixpkgs_3"
+      },
      "locked": {
-        "lastModified": 1682426789,
-        "narHash": "sha256-UqnLmJESRZE0tTEaGbRAw05Hm19TWIPA+R3meqi5I4w=",
-        "owner": "rust-lang",
-        "repo": "rust-analyzer",
-        "rev": "943d2a8a1ca15e8b28a1f51f5a5c135e3728da04",
+        "lastModified": 1690510705,
+        "narHash": "sha256-6mjs3Gl9/xrseFh9iNcNq1u5yJ/MIoAmjoaG7SXZDIE=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "851ae4c128905a62834d53ce7704ebc1ba481bea",
        "type": "github"
      },
      "original": {
-        "owner": "rust-lang",
-        "ref": "nightly",
-        "repo": "rust-analyzer",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
        "type": "github"
      }
    },
@@ -267,6 +285,36 @@
        "repo": "default",
        "type": "github"
      }
+    },
+    "systems_2": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "systems_3": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
    }
  },
  "root": "root",
@@ -39,27 +39,27 @@

 {
  inputs = {
-    # Use the master/unstable branch of nixpkgs. The latest stable, 22.11,
-    # does not contain 'perl536Packages.NetAsyncHTTP', needed by Sytest.
+    # Use the master/unstable branch of nixpkgs. Used to fetch the latest
+    # available versions of packages.
    nixpkgs.url = "github:NixOS/nixpkgs/master";
    # Output a development shell for x86_64/aarch64 Linux/Darwin (MacOS).
    systems.url = "github:nix-systems/default";
    # A development environment manager built on Nix. See https://devenv.sh.
    devenv.url = "github:cachix/devenv/main";
-    # Rust toolchains and rust-analyzer nightly.
-    fenix = {
-      url = "github:nix-community/fenix";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
+    # Rust toolchain.
+    rust-overlay.url = "github:oxalica/rust-overlay";
  };

-  outputs = { self, nixpkgs, devenv, systems, ... } @ inputs:
+  outputs = { self, nixpkgs, devenv, systems, rust-overlay, ... } @ inputs:
    let
      forEachSystem = nixpkgs.lib.genAttrs (import systems);
    in {
      devShells = forEachSystem (system:
        let
-          pkgs = nixpkgs.legacyPackages.${system};
+          overlays = [ (import rust-overlay) ];
+          pkgs = import nixpkgs {
+            inherit system overlays;
+          };
        in {
          # Everything is configured via devenv - a Nix module for creating declarative
          # developer environments. See https://devenv.sh/reference/options/ for a list
@@ -76,6 +76,20 @@
                # Configure packages to install.
                # Search for package names at https://search.nixos.org/packages?channel=unstable
                packages = with pkgs; [
+                  # The rust toolchain and related tools.
+                  # This will install the "default" profile of rust components.
+                  # https://rust-lang.github.io/rustup/concepts/profiles.html
+                  #
+                  # NOTE: We currently need to set the Rust version unnecessarily high
+                  # in order to work around https://github.com/matrix-org/synapse/issues/15939
+                  (rust-bin.stable."1.70.0".default.override {
+                    # Additionally install the "rust-src" extension to allow diving into the
+                    # Rust source code in an IDE (rust-analyzer will also make use of it).
+                    extensions = [ "rust-src" ];
+                  })
+                  # The rust-analyzer language server implementation.
+                  rust-analyzer
+
                  # Native dependencies for running Synapse.
                  icu
                  libffi
@@ -124,12 +138,11 @@
                # Install dependencies for the additional programming languages
                # involved with Synapse development.
                #
-                # * Rust is used for developing and running Synapse.
                # * Golang is needed to run the Complement test suite.
                # * Perl is needed to run the SyTest test suite.
+                # * Rust is used for developing and running Synapse.
+                #   It is installed manually with `packages` above.
                languages.go.enable = true;
-                languages.rust.enable = true;
-                languages.rust.version = "stable";
                languages.perl.enable = true;

                # Postgres is needed to run Synapse with postgres support and
@@ -178,7 +191,7 @@
                  EOF
                '';
                # Start synapse when `devenv up` is run.
-                processes.synapse.exec = "poetry run python -m synapse.app.homeserver -c homeserver.yaml --config-directory homeserver-config-overrides.d";
+                processes.synapse.exec = "poetry run python -m synapse.app.homeserver -c homeserver.yaml -c homeserver-config-overrides.d";

                # Define the perl modules we require to run SyTest.
                #
@@ -2,17 +2,29 @@
 namespace_packages = True
 plugins = pydantic.mypy, mypy_zope:plugin, scripts-dev/mypy_synapse_plugin.py
 follow_imports = normal
-check_untyped_defs = True
 show_error_codes = True
 show_traceback = True
 mypy_path = stubs
 warn_unreachable = True
-warn_unused_ignores = True
 local_partial_types = True
 no_implicit_optional = True
+
+# Strict checks, see mypy --help
+warn_unused_configs = True
+# disallow_any_generics = True
+disallow_subclassing_any = True
+# disallow_untyped_calls = True
 disallow_untyped_defs = True
-strict_equality = True
+disallow_incomplete_defs = True
+# check_untyped_defs = True
+# disallow_untyped_decorators = True
 warn_redundant_casts = True
+warn_unused_ignores = True
+# warn_return_any = True
+# no_implicit_reexport = True
+strict_equality = True
+strict_concatenate = True
+
 # Run mypy type checking with the minimum supported Python version to catch new usage
 # that isn't backwards-compatible (types, overloads, etc).
 python_version = 3.8
@@ -31,6 +43,14 @@ warn_unused_ignores = False

 [mypy-synapse.util.caches.treecache]
 disallow_untyped_defs = False
+disallow_incomplete_defs = False
+
+[mypy-synapse.util.manhole]
+# This module imports something from Twisted which has a bad annotation in Twisted trunk,
+# but is unannotated in Twisted's latest release. We want to type-ignore the problem 
+# in the twisted trunk job, even though it has no effect on normal mypy runs.
+warn_unused_ignores = False
+

 ;; Dependencies without annotations
 ;; Before ignoring a module, check to see if type stubs are available.
@@ -40,18 +60,18 @@ disallow_untyped_defs = False
 ;; which we can pull in as a dev dependency by adding to `pyproject.toml`'s
 ;; `[tool.poetry.dev-dependencies]` list.

+# https://github.com/lepture/authlib/issues/460
 [mypy-authlib.*]
 ignore_missing_imports = True

 [mypy-ijson.*]
 ignore_missing_imports = True

-[mypy-lxml]
-ignore_missing_imports = True
-
+# https://github.com/msgpack/msgpack-python/issues/448
 [mypy-msgpack]
 ignore_missing_imports = True

+# https://github.com/wolever/parameterized/issues/143
 [mypy-parameterized.*]
 ignore_missing_imports = True

@@ -73,6 +93,7 @@ ignore_missing_imports = True
 [mypy-srvlookup.*]
 ignore_missing_imports = True

+# https://github.com/twisted/treq/pull/366
 [mypy-treq.*]
 ignore_missing_imports = True

@@ -89,7 +89,7 @@ manifest-path = "rust/Cargo.toml"

 [tool.poetry]
 name = "matrix-synapse"
-version = "1.85.0rc2"
+version = "1.90.0"
 description = "Homeserver for the Matrix decentralised comms protocol"
 authors = ["Matrix.org Team and Contributors <packages@matrix.org>"]
 license = "Apache-2.0"
@@ -147,7 +147,7 @@ synapse_review_recent_signups = "synapse._scripts.review_recent_signups:main"
 update_synapse_database = "synapse._scripts.update_synapse_database:main"

 [tool.poetry.dependencies]
-python = "^3.7.1"
+python = "^3.8.0"

 # Mandatory Dependencies
 # ----------------------
@@ -203,11 +203,9 @@ ijson = ">=3.1.4"
 matrix-common = "^1.3.0"
 # We need packaging.requirements.Requirement, added in 16.1.
 packaging = ">=16.1"
-# At the time of writing, we only use functions from the version `importlib.metadata`
-# which shipped in Python 3.8. This corresponds to version 1.4 of the backport.
-importlib_metadata = { version = ">=1.4", python = "<3.8" }
 # This is the most recent version of Pydantic with available on common distros.
-pydantic = ">=1.7.4"
+# We are currently incompatible with >=2.0.0: (https://github.com/matrix-org/synapse/issues/15858)
+pydantic = "^1.7.4"

 # This is for building the rust components during "poetry install", which
 # currently ignores the `build-system.requires` directive (c.f.
@@ -311,9 +309,10 @@ all = [
 # We pin black so that our tests don't start failing on new releases.
 isort = ">=5.10.1"
 black = ">=22.3.0"
-ruff = "0.0.265"
+ruff = "0.0.277"

 # Typechecking
+lxml-stubs = ">=0.4.0"
 mypy = "*"
 mypy-zope = "*"
 types-bleach = ">=4.1.0"
@@ -374,7 +373,15 @@ build-backend = "poetry.core.masonry.api"

 [tool.cibuildwheel]
 # Skip unsupported platforms (by us or by Rust).
-skip = "cp36* *-musllinux_i686 pp*aarch64 *-musllinux_aarch64"
+# See https://cibuildwheel.readthedocs.io/en/stable/options/#build-skip for the list of build targets.
+# We skip:
+#  - CPython 3.6 and 3.7: EOLed
+#  - PyPy 3.7: we only support Python 3.8+
+#  - musllinux i686: excluded to reduce number of wheels we build.
+#    c.f. https://github.com/matrix-org/synapse/pull/12595#discussion_r963107677
+#  - PyPy on Aarch64 and musllinux on aarch64: too slow to build.
+#    c.f. https://github.com/matrix-org/synapse/pull/14259
+skip = "cp36* cp37* pp37* *-musllinux_i686 pp*aarch64 *-musllinux_aarch64"

 # We need a rust compiler
 before-all =  "curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain stable -y --profile minimal"
@@ -7,7 +7,7 @@ name = "synapse"
 version = "0.1.0"

 edition = "2021"
-rust-version = "1.58.1"
+rust-version = "1.60.0"

 [lib]
 name = "synapse"
@@ -13,7 +13,8 @@
 // limitations under the License.

 #![feature(test)]
-use std::collections::BTreeSet;
+
+use std::borrow::Cow;

 use synapse::push::{
    evaluator::PushRuleEvaluator, Condition, EventMatchCondition, FilteredPushRules, JsonValue,
@@ -28,15 +29,15 @@ fn bench_match_exact(b: &mut Bencher) {
    let flattened_keys = [
        (
            "type".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("m.text".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("m.text"))),
        ),
        (
            "room_id".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("!room:server".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("!room:server"))),
        ),
        (
            "content.body".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("test message".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("test message"))),
        ),
    ]
    .into_iter()
@@ -73,15 +74,15 @@ fn bench_match_word(b: &mut Bencher) {
    let flattened_keys = [
        (
            "type".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("m.text".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("m.text"))),
        ),
        (
            "room_id".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("!room:server".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("!room:server"))),
        ),
        (
            "content.body".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("test message".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("test message"))),
        ),
    ]
    .into_iter()
@@ -118,15 +119,15 @@ fn bench_match_word_miss(b: &mut Bencher) {
    let flattened_keys = [
        (
            "type".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("m.text".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("m.text"))),
        ),
        (
            "room_id".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("!room:server".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("!room:server"))),
        ),
        (
            "content.body".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("test message".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("test message"))),
        ),
    ]
    .into_iter()
@@ -163,15 +164,15 @@ fn bench_eval_message(b: &mut Bencher) {
    let flattened_keys = [
        (
            "type".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("m.text".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("m.text"))),
        ),
        (
            "room_id".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("!room:server".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("!room:server"))),
        ),
        (
            "content.body".to_string(),
-            JsonValue::Value(SimpleJsonValue::Str("test message".to_string())),
+            JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("test message"))),
        ),
    ]
    .into_iter()
@@ -197,7 +198,6 @@ fn bench_eval_message(b: &mut Bencher) {
        false,
        false,
        false,
-        false,
    );

    b.iter(|| eval.run(&rules, Some("bob"), Some("person")));
@@ -63,22 +63,6 @@ pub const BASE_PREPEND_OVERRIDE_RULES: &[PushRule] = &[PushRule {
 }];

 pub const BASE_APPEND_OVERRIDE_RULES: &[PushRule] = &[
-    // We don't want to notify on edits. Not only can this be confusing in real
-    // time (2 notifications, one message) but it's especially confusing
-    // if a bridge needs to edit a previously backfilled message.
-    PushRule {
-        rule_id: Cow::Borrowed("global/override/.com.beeper.suppress_edits"),
-        priority_class: 5,
-        conditions: Cow::Borrowed(&[Condition::Known(KnownCondition::EventMatch(
-            EventMatchCondition {
-                key: Cow::Borrowed("content.m\\.relates_to.rel_type"),
-                pattern: Cow::Borrowed("m.replace"),
-            },
-        ))]),
-        actions: Cow::Borrowed(&[]),
-        default: true,
-        default_enabled: true,
-    },
    PushRule {
        rule_id: Cow::Borrowed("global/override/.m.rule.suppress_notices"),
        priority_class: 5,
@@ -142,11 +126,11 @@ pub const BASE_APPEND_OVERRIDE_RULES: &[PushRule] = &[
        default_enabled: true,
    },
    PushRule {
-        rule_id: Cow::Borrowed(".org.matrix.msc3952.is_user_mention"),
+        rule_id: Cow::Borrowed("global/override/.m.rule.is_user_mention"),
        priority_class: 5,
        conditions: Cow::Borrowed(&[Condition::Known(
            KnownCondition::ExactEventPropertyContainsType(EventPropertyIsTypeCondition {
-                key: Cow::Borrowed("content.org\\.matrix\\.msc3952\\.mentions.user_ids"),
+                key: Cow::Borrowed(r"content.m\.mentions.user_ids"),
                value_type: Cow::Borrowed(&EventMatchPatternType::UserId),
            }),
        )]),
@@ -163,12 +147,12 @@ pub const BASE_APPEND_OVERRIDE_RULES: &[PushRule] = &[
        default_enabled: true,
    },
    PushRule {
-        rule_id: Cow::Borrowed(".org.matrix.msc3952.is_room_mention"),
+        rule_id: Cow::Borrowed("global/override/.m.rule.is_room_mention"),
        priority_class: 5,
        conditions: Cow::Borrowed(&[
            Condition::Known(KnownCondition::EventPropertyIs(EventPropertyIsCondition {
-                key: Cow::Borrowed("content.org\\.matrix\\.msc3952\\.mentions.room"),
-                value: Cow::Borrowed(&SimpleJsonValue::Bool(true)),
+                key: Cow::Borrowed(r"content.m\.mentions.room"),
+                value: Cow::Owned(SimpleJsonValue::Bool(true)),
            })),
            Condition::Known(KnownCondition::SenderNotificationPermission {
                key: Cow::Borrowed("room"),
@@ -241,6 +225,21 @@ pub const BASE_APPEND_OVERRIDE_RULES: &[PushRule] = &[
        default: true,
        default_enabled: true,
    },
+    // We don't want to notify on edits *unless* the edit directly mentions a
+    // user, which is handled above.
+    PushRule {
+        rule_id: Cow::Borrowed("global/override/.org.matrix.msc3958.suppress_edits"),
+        priority_class: 5,
+        conditions: Cow::Borrowed(&[Condition::Known(KnownCondition::EventPropertyIs(
+            EventPropertyIsCondition {
+                key: Cow::Borrowed(r"content.m\.relates_to.rel_type"),
+                value: Cow::Owned(SimpleJsonValue::Str(Cow::Borrowed("m.replace"))),
+            },
+        ))]),
+        actions: Cow::Borrowed(&[]),
+        default: true,
+        default_enabled: true,
+    },
    PushRule {
        rule_id: Cow::Borrowed("global/override/.org.matrix.msc3930.rule.poll_response"),
        priority_class: 5,
@@ -70,7 +70,9 @@ pub struct PushRuleEvaluator {
    /// The "content.body", if any.
    body: String,

-    /// True if the event has a mentions property and MSC3952 support is enabled.
+    /// True if the event has a m.mentions property. (Note that this is a separate
+    /// flag instead of checking flattened_keys since the m.mentions property
+    /// might be an empty map and not appear in flattened_keys.
    has_mentions: bool,

    /// The number of users in the room.
@@ -115,7 +117,7 @@ impl PushRuleEvaluator {
        msc3931_enabled: bool,
    ) -> Result<Self, Error> {
        let body = match flattened_keys.get("content.body") {
-            Some(JsonValue::Value(SimpleJsonValue::Str(s))) => s.clone(),
+            Some(JsonValue::Value(SimpleJsonValue::Str(s))) => s.clone().into_owned(),
            _ => String::new(),
        };

@@ -155,9 +157,7 @@ impl PushRuleEvaluator {
            let rule_id = &push_rule.rule_id().to_string();

            // For backwards-compatibility the legacy mention rules are disabled
-            // if the event contains the 'm.mentions' property (and if the
-            // experimental feature is enabled, both of these are represented
-            // by the has_mentions flag).
+            // if the event contains the 'm.mentions' property.
            if self.has_mentions
                && (rule_id == "global/override/.m.rule.contains_display_name"
                    || rule_id == "global/content/.m.rule.contains_user_name"
@@ -313,13 +313,15 @@ impl PushRuleEvaluator {
                };

                let pattern = match &*exact_event_match.value_type {
-                    EventMatchPatternType::UserId => user_id,
-                    EventMatchPatternType::UserLocalpart => get_localpart_from_id(user_id)?,
+                    EventMatchPatternType::UserId => user_id.to_owned(),
+                    EventMatchPatternType::UserLocalpart => {
+                        get_localpart_from_id(user_id)?.to_owned()
+                    }
                };

                self.match_event_property_contains(
                    exact_event_match.key.clone(),
-                    Cow::Borrowed(&SimpleJsonValue::Str(pattern.to_string())),
+                    Cow::Borrowed(&SimpleJsonValue::Str(Cow::Owned(pattern))),
                )?
            }
            KnownCondition::ContainsDisplayName => {
@@ -494,7 +496,7 @@ fn push_rule_evaluator() {
    let mut flattened_keys = BTreeMap::new();
    flattened_keys.insert(
        "content.body".to_string(),
-        JsonValue::Value(SimpleJsonValue::Str("foo bar bob hello".to_string())),
+        JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("foo bar bob hello"))),
    );
    let evaluator = PushRuleEvaluator::py_new(
        flattened_keys,
@@ -522,7 +524,7 @@ fn test_requires_room_version_supports_condition() {
    let mut flattened_keys = BTreeMap::new();
    flattened_keys.insert(
        "content.body".to_string(),
-        JsonValue::Value(SimpleJsonValue::Str("foo bar bob hello".to_string())),
+        JsonValue::Value(SimpleJsonValue::Str(Cow::Borrowed("foo bar bob hello"))),
    );
    let flags = vec![RoomVersionFeatures::ExtensibleEvents.as_str().to_string()];
    let evaluator = PushRuleEvaluator::py_new(
@@ -562,7 +564,7 @@ fn test_requires_room_version_supports_condition() {
    };
    let rules = PushRules::new(vec![custom_rule]);
    result = evaluator.run(
-        &FilteredPushRules::py_new(rules, BTreeMap::new(), true, false, true, false, false),
+        &FilteredPushRules::py_new(rules, BTreeMap::new(), true, false, true, false),
        None,
        None,
    );
@@ -256,7 +256,7 @@ impl<'de> Deserialize<'de> for Action {
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq)]
 #[serde(untagged)]
 pub enum SimpleJsonValue {
-    Str(String),
+    Str(Cow<'static, str>),
    Int(i64),
    Bool(bool),
    Null,
@@ -265,7 +265,7 @@ pub enum SimpleJsonValue {
 impl<'source> FromPyObject<'source> for SimpleJsonValue {
    fn extract(ob: &'source PyAny) -> PyResult<Self> {
        if let Ok(s) = <PyString as pyo3::PyTryFrom>::try_from(ob) {
-            Ok(SimpleJsonValue::Str(s.to_string()))
+            Ok(SimpleJsonValue::Str(Cow::Owned(s.to_string())))
        // A bool *is* an int, ensure we try bool first.
        } else if let Ok(b) = <PyBool as pyo3::PyTryFrom>::try_from(ob) {
            Ok(SimpleJsonValue::Bool(b.extract()?))
@@ -527,7 +527,6 @@ pub struct FilteredPushRules {
    msc1767_enabled: bool,
    msc3381_polls_enabled: bool,
    msc3664_enabled: bool,
-    msc3952_intentional_mentions: bool,
    msc3958_suppress_edits_enabled: bool,
 }

@@ -540,7 +539,6 @@ impl FilteredPushRules {
        msc1767_enabled: bool,
        msc3381_polls_enabled: bool,
        msc3664_enabled: bool,
-        msc3952_intentional_mentions: bool,
        msc3958_suppress_edits_enabled: bool,
    ) -> Self {
        Self {
@@ -549,7 +547,6 @@ impl FilteredPushRules {
            msc1767_enabled,
            msc3381_polls_enabled,
            msc3664_enabled,
-            msc3952_intentional_mentions,
            msc3958_suppress_edits_enabled,
        }
    }
@@ -587,12 +584,8 @@ impl FilteredPushRules {
                    return false;
                }

-                if !self.msc3952_intentional_mentions && rule.rule_id.contains("org.matrix.msc3952")
-                {
-                    return false;
-                }
                if !self.msc3958_suppress_edits_enabled
-                    && rule.rule_id == "global/override/.com.beeper.suppress_edits"
+                    && rule.rule_id == "global/override/.org.matrix.msc3958.suppress_edits"
                {
                    return false;
                }
@@ -20,15 +20,21 @@ from concurrent.futures import ThreadPoolExecutor
 from types import FrameType
 from typing import Collection, Optional, Sequence, Set

+# These are expanded inside the dockerfile to be a fully qualified image name.
+# e.g. docker.io/library/debian:bullseye
+#
+# If an EOL is forced by a Python version and we're dropping support for it, make sure
+# to remove references to the distibution across Synapse (search for "bullseye" for
+# example)
 DISTS = (
-    "debian:buster",  # oldstable: EOL 2022-08
-    "debian:bullseye",
-    "debian:bookworm",
-    "debian:sid",
-    "ubuntu:focal",  # 20.04 LTS (our EOL forced by Py38 on 2024-10-14)
-    "ubuntu:jammy",  # 22.04 LTS (EOL 2027-04)
-    "ubuntu:kinetic",  # 22.10 (EOL 2023-07-20)
-    "ubuntu:lunar",  # 23.04 (EOL 2024-01)
+    "debian:bullseye",  # (EOL ~2024-07) (our EOL forced by Python 3.9 is 2025-10-05)
+    "debian:bookworm",  # (EOL not specified yet) (our EOL forced by Python 3.11 is 2027-10-24)
+    "debian:sid",  # (EOL not specified yet) (our EOL forced by Python 3.11 is 2027-10-24)
+    "ubuntu:focal",  # 20.04 LTS (EOL 2025-04) (our EOL forced by Python 3.8 is 2024-10-14)
+    "ubuntu:jammy",  # 22.04 LTS (EOL 2027-04) (our EOL forced by Python 3.10 is 2026-10-04)
+    "ubuntu:kinetic",  # 22.10 (EOL 2023-07-20) (our EOL forced by Python 3.10 is 2026-10-04)
+    "ubuntu:lunar",  # 23.04 (EOL 2024-01) (our EOL forced by Python 3.11 is 2027-10-24)
+    "debian:trixie",  # (EOL not specified yet)
 )

 DESC = """\
@@ -41,7 +47,7 @@ can be passed on the commandline for debugging.
 projdir = os.path.dirname(os.path.dirname(os.path.realpath(__file__)))


-class Builder(object):
+class Builder:
    def __init__(
        self,
        redirect_stdout: bool = False,
@@ -43,7 +43,7 @@ def main(force_colors: bool) -> None:
    diffs: List[git.Diff] = repo.remote().refs.develop.commit.diff(None)

    # Get the schema version of the local file to check against current schema on develop
-    with open("synapse/storage/schema/__init__.py", "r") as file:
+    with open("synapse/storage/schema/__init__.py") as file:
        local_schema = file.read()
    new_locals: Dict[str, Any] = {}
    exec(local_schema, new_locals)
@@ -214,7 +214,7 @@ fi

 extra_test_args=()

-test_tags="synapse_blacklist,msc3787,msc3874,msc3890,msc3391,msc3930,faster_joins"
+test_tags="synapse_blacklist,msc3874,msc3890,msc3391,msc3930,faster_joins"

 # All environment variables starting with PASS_ will be shared.
 # (The prefix is stripped off before reaching the container.)
@@ -246,10 +246,6 @@ else
  else
    export PASS_SYNAPSE_COMPLEMENT_DATABASE=sqlite
  fi
-
-  # The tests for importing historical messages (MSC2716)
-  # only pass with monoliths, currently.
-  test_tags="$test_tags,msc2716"
 fi

 if [[ -n "$ASYNCIO_REACTOR" ]]; then
@@ -257,6 +253,10 @@ if [[ -n "$ASYNCIO_REACTOR" ]]; then
  export PASS_SYNAPSE_COMPLEMENT_USE_ASYNCIO_REACTOR=true
 fi

+if [[ -n "$UNIX_SOCKETS" ]]; then
+  # Enable full on Unix socket mode for Synapse, Redis and Postgresql
+  export PASS_SYNAPSE_USE_UNIX_SOCKET=1
+fi

 if [[ -n "$SYNAPSE_TEST_LOG_LEVEL" ]]; then
  # Set the log level to what is desired
@@ -269,6 +269,10 @@ if [[ -n "$SYNAPSE_TEST_LOG_LEVEL" ]]; then
  export PASS_SYNAPSE_LOG_SENSITIVE=1
 fi

+# Log a few more useful things for a developer attempting to debug something
+# particularly tricky.
+export PASS_SYNAPSE_LOG_TESTING=1
+
 # Run the tests!
 echo "Images built; running complement"
 cd "$COMPLEMENT_DIR"
@@ -136,11 +136,11 @@ def request(
        authorization_headers.append(header)
        print("Authorization: %s" % header, file=sys.stderr)

-    dest = "matrix://%s%s" % (destination, path)
+    dest = "matrix-federation://%s%s" % (destination, path)
    print("Requesting %s" % dest, file=sys.stderr)

    s = requests.Session()
-    s.mount("matrix://", MatrixConnectionAdapter())
+    s.mount("matrix-federation://", MatrixConnectionAdapter())

    headers: Dict[str, str] = {
        "Authorization": authorization_headers[0],
@@ -247,7 +247,7 @@ def main() -> None:


 def read_args_from_config(args: argparse.Namespace) -> None:
-    with open(args.config, "r") as fh:
+    with open(args.config) as fh:
        config = yaml.safe_load(fh)

        if not args.server_name:
@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 # Copyright 2020 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -145,7 +145,7 @@ Example usage:


 def read_args_from_config(args: argparse.Namespace) -> None:
-    with open(args.config, "r") as fh:
+    with open(args.config) as fh:
        config = yaml.safe_load(fh)
        if not args.server_name:
            args.server_name = config["server_name"]
@@ -46,7 +46,6 @@ class FilteredPushRules:
        msc1767_enabled: bool,
        msc3381_polls_enabled: bool,
        msc3664_enabled: bool,
-        msc3952_intentional_mentions: bool,
        msc3958_suppress_edits_enabled: bool,
    ): ...
    def rules(self) -> Collection[Tuple[PushRule, bool]]: ...
@@ -25,8 +25,12 @@ from synapse.util.rust import check_rust_lib_up_to_date
 from synapse.util.stringutils import strtobool

 # Check that we're not running on an unsupported Python version.
-if sys.version_info < (3, 7):
-    print("Synapse requires Python 3.7 or above.")
+#
+# Note that we use an (unneeded) variable here so that pyupgrade doesn't nuke the
+# if-statement completely.
+py_version = sys.version_info
+if py_version < (3, 8):
+    print("Synapse requires Python 3.8 or above.")
    sys.exit(1)

 # Allow using the asyncio reactor via env var.
@@ -78,7 +82,7 @@ try:
 except ImportError:
    pass

-import synapse.util
+import synapse.util  # noqa: E402

 __version__ = synapse.util.SYNAPSE_VERSION

@@ -61,6 +61,7 @@ from synapse.storage.databases.main.deviceinbox import DeviceInboxBackgroundUpda
 from synapse.storage.databases.main.devices import DeviceBackgroundUpdateStore
 from synapse.storage.databases.main.e2e_room_keys import EndToEndRoomKeyBackgroundStore
 from synapse.storage.databases.main.end_to_end_keys import EndToEndKeyBackgroundStore
+from synapse.storage.databases.main.event_federation import EventFederationWorkerStore
 from synapse.storage.databases.main.event_push_actions import EventPushActionsStore
 from synapse.storage.databases.main.events_bg_updates import (
    EventsBackgroundUpdatesStore,
@@ -122,7 +123,7 @@ BOOLEAN_COLUMNS = {
    "redactions": ["have_censored"],
    "room_stats_state": ["is_federatable"],
    "rooms": ["is_public", "has_auth_chain_index"],
-    "users": ["shadow_banned", "approved"],
+    "users": ["shadow_banned", "approved", "locked"],
    "un_partial_stated_event_stream": ["rejection_status_changed"],
    "users_who_share_rooms": ["share_private"],
    "per_user_experimental_features": ["enabled"],
@@ -196,6 +197,11 @@ IGNORED_TABLES = {
    "ui_auth_sessions",
    "ui_auth_sessions_credentials",
    "ui_auth_sessions_ips",
+    # Ignore the worker locks table, as a) there shouldn't be any acquired locks
+    # after porting, and b) the circular foreign key constraints make it hard to
+    # port.
+    "worker_read_write_locks_mode",
+    "worker_read_write_locks",
 }


@@ -239,6 +245,7 @@ class Store(
    PresenceBackgroundUpdateStore,
    ReceiptsBackgroundUpdateStore,
    RelationsWorkerStore,
+    EventFederationWorkerStore,
 ):
    def execute(self, f: Callable[..., R], *args: Any, **kwargs: Any) -> Awaitable[R]:
        return self.db_pool.runInteraction(f.__name__, f, *args, **kwargs)
@@ -754,7 +761,7 @@ class Porter:

            # Step 2. Set up sequences
            #
-            # We do this before porting the tables so that event if we fail half
+            # We do this before porting the tables so that even if we fail half
            # way through the postgres DB always have sequences that are greater
            # than their respective tables. If we don't then creating the
            # `DataStore` object will fail due to the inconsistency.
@@ -762,6 +769,10 @@ class Porter:
            await self._setup_state_group_id_seq()
            await self._setup_user_id_seq()
            await self._setup_events_stream_seqs()
+            await self._setup_sequence(
+                "un_partial_stated_event_stream_sequence",
+                ("un_partial_stated_event_stream",),
+            )
            await self._setup_sequence(
                "device_inbox_sequence", ("device_inbox", "device_federation_outbox")
            )
@@ -772,6 +783,11 @@ class Porter:
            await self._setup_sequence("receipts_sequence", ("receipts_linearized",))
            await self._setup_sequence("presence_stream_sequence", ("presence_stream",))
            await self._setup_auth_chain_sequence()
+            await self._setup_sequence(
+                "application_services_txn_id_seq",
+                ("application_services_txns",),
+                "txn_id",
+            )

            # Step 3. Get tables.
            self.progress.set_state("Fetching tables")
@@ -803,7 +819,9 @@ class Porter:
            )
            # Map from table name to args passed to `handle_table`, i.e. a tuple
            # of: `postgres_size`, `table_size`, `forward_chunk`, `backward_chunk`.
-            tables_to_port_info_map = {r[0]: r[1:] for r in setup_res}
+            tables_to_port_info_map = {
+                r[0]: r[1:] for r in setup_res if r[0] not in IGNORED_TABLES
+            }

            # Step 5. Do the copying.
            #
@@ -1074,7 +1092,10 @@ class Porter:
        )

    async def _setup_sequence(
-        self, sequence_name: str, stream_id_tables: Iterable[str]
+        self,
+        sequence_name: str,
+        stream_id_tables: Iterable[str],
+        column_name: str = "stream_id",
    ) -> None:
        """Set a sequence to the correct value."""
        current_stream_ids = []
@@ -1084,7 +1105,7 @@ class Porter:
                await self.sqlite_store.db_pool.simple_select_one_onecol(
                    table=stream_id_table,
                    keyvalues={},
-                    retcol="COALESCE(MAX(stream_id), 1)",
+                    retcol=f"COALESCE(MAX({column_name}), 1)",
                    allow_none=True,
                ),
            )
@@ -1184,10 +1205,10 @@ class CursesProgress(Progress):
        self.total_processed = 0
        self.total_remaining = 0

-        super(CursesProgress, self).__init__()
+        super().__init__()

    def update(self, table: str, num_done: int) -> None:
-        super(CursesProgress, self).update(table, num_done)
+        super().update(table, num_done)

        self.total_processed = 0
        self.total_remaining = 0
@@ -1283,7 +1304,7 @@ class TerminalProgress(Progress):
    """Just prints progress to the terminal"""

    def update(self, table: str, num_done: int) -> None:
-        super(TerminalProgress, self).update(table, num_done)
+        super().update(table, num_done)

        data = self.tables[table]

@@ -1369,6 +1390,9 @@ def main() -> None:
        sys.stderr.write("Database must use the 'psycopg2' connector.\n")
        sys.exit(3)

+    # Don't run the background tasks that get started by the data stores.
+    hs_config["run_background_tasks_on"] = "some_other_process"
+
    config = HomeServerConfig()
    config.parse_config_dict(hs_config, "", "")

@@ -38,7 +38,7 @@ class MockHomeserver(HomeServer):
    DATASTORE_CLASS = DataStore  # type: ignore [assignment]

    def __init__(self, config: HomeServerConfig):
-        super(MockHomeserver, self).__init__(
+        super().__init__(
            hostname=config.server.server_name,
            config=config,
            reactor=reactor,
@@ -0,0 +1,176 @@
+# Copyright 2023 The Matrix.org Foundation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from typing import Optional, Tuple
+
+from typing_extensions import Protocol
+
+from twisted.web.server import Request
+
+from synapse.appservice import ApplicationService
+from synapse.http.site import SynapseRequest
+from synapse.types import Requester
+
+# guests always get this device id.
+GUEST_DEVICE_ID = "guest_device"
+
+
+class Auth(Protocol):
+    """The interface that an auth provider must implement."""
+
+    async def check_user_in_room(
+        self,
+        room_id: str,
+        requester: Requester,
+        allow_departed_users: bool = False,
+    ) -> Tuple[str, Optional[str]]:
+        """Check if the user is in the room, or was at some point.
+        Args:
+            room_id: The room to check.
+
+            user_id: The user to check.
+
+            current_state: Optional map of the current state of the room.
+                If provided then that map is used to check whether they are a
+                member of the room. Otherwise the current membership is
+                loaded from the database.
+
+            allow_departed_users: if True, accept users that were previously
+                members but have now departed.
+
+        Raises:
+            AuthError if the user is/was not in the room.
+        Returns:
+            The current membership of the user in the room and the
+            membership event ID of the user.
+        """
+
+    async def get_user_by_req(
+        self,
+        request: SynapseRequest,
+        allow_guest: bool = False,
+        allow_expired: bool = False,
+        allow_locked: bool = False,
+    ) -> Requester:
+        """Get a registered user's ID.
+
+        Args:
+            request: An HTTP request with an access_token query parameter.
+            allow_guest: If False, will raise an AuthError if the user making the
+                request is a guest.
+            allow_expired: If True, allow the request through even if the account
+                is expired, or session token lifetime has ended. Note that
+                /login will deliver access tokens regardless of expiration.
+
+        Returns:
+            Resolves to the requester
+        Raises:
+            InvalidClientCredentialsError if no user by that token exists or the token
+                is invalid.
+            AuthError if access is denied for the user in the access token
+        """
+
+    async def validate_appservice_can_control_user_id(
+        self, app_service: ApplicationService, user_id: str
+    ) -> None:
+        """Validates that the app service is allowed to control
+        the given user.
+
+        Args:
+            app_service: The app service that controls the user
+            user_id: The author MXID that the app service is controlling
+
+        Raises:
+            AuthError: If the application service is not allowed to control the user
+                (user namespace regex does not match, wrong homeserver, etc)
+                or if the user has not been registered yet.
+        """
+
+    async def get_user_by_access_token(
+        self,
+        token: str,
+        allow_expired: bool = False,
+    ) -> Requester:
+        """Validate access token and get user_id from it
+
+        Args:
+            token: The access token to get the user by
+            allow_expired: If False, raises an InvalidClientTokenError
+                if the token is expired
+
+        Raises:
+            InvalidClientTokenError if a user by that token exists, but the token is
+                expired
+            InvalidClientCredentialsError if no user by that token exists or the token
+                is invalid
+        """
+
+    async def is_server_admin(self, requester: Requester) -> bool:
+        """Check if the given user is a local server admin.
+
+        Args:
+            requester: user to check
+
+        Returns:
+            True if the user is an admin
+        """
+
+    async def check_can_change_room_list(
+        self, room_id: str, requester: Requester
+    ) -> bool:
+        """Determine whether the user is allowed to edit the room's entry in the
+        published room list.
+
+        Args:
+            room_id
+            user
+        """
+
+    @staticmethod
+    def has_access_token(request: Request) -> bool:
+        """Checks if the request has an access_token.
+
+        Returns:
+            False if no access_token was given, True otherwise.
+        """
+
+    @staticmethod
+    def get_access_token_from_request(request: Request) -> str:
+        """Extracts the access_token from the request.
+
+        Args:
+            request: The http request.
+        Returns:
+            The access_token
+        Raises:
+            MissingClientTokenError: If there isn't a single access_token in the
+                request
+        """
+
+    async def check_user_in_room_or_world_readable(
+        self, room_id: str, requester: Requester, allow_departed_users: bool = False
+    ) -> Tuple[str, Optional[str]]:
+        """Checks that the user is or was in the room or the room is world
+        readable. If it isn't then an exception is raised.
+
+        Args:
+            room_id: room to check
+            user_id: user to check
+            allow_departed_users: if True, accept users that were previously
+                members but have now departed
+
+        Returns:
+            Resolves to the current membership of the user in the room and the
+            membership event ID of the user. If the user is not in the room and
+            never has been, then `(Membership.JOIN, None)` is returned.
+        """
@@ -1,4 +1,4 @@
-# Copyright 2014 - 2016 OpenMarket Ltd
+# Copyright 2023 The Matrix.org Foundation.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -14,7 +14,6 @@
 import logging
 from typing import TYPE_CHECKING, Optional, Tuple

-import pymacaroons
 from netaddr import IPAddress

 from twisted.web.server import Request
@@ -24,19 +23,11 @@ from synapse.api.constants import EventTypes, HistoryVisibility, Membership
 from synapse.api.errors import (
    AuthError,
    Codes,
-    InvalidClientTokenError,
    MissingClientTokenError,
    UnstableSpecAuthError,
 )
 from synapse.appservice import ApplicationService
-from synapse.http import get_request_user_agent
-from synapse.http.site import SynapseRequest
-from synapse.logging.opentracing import (
-    active_span,
-    force_tracing,
-    start_active_span,
-    trace,
-)
+from synapse.logging.opentracing import trace
 from synapse.types import Requester, create_requester
 from synapse.util.cancellation import cancellable

@@ -46,26 +37,13 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)


-# guests always get this device id.
-GUEST_DEVICE_ID = "guest_device"
-
-
-class Auth:
-    """
-    This class contains functions for authenticating users of our client-server API.
-    """
+class BaseAuth:
+    """Common base class for all auth implementations."""

    def __init__(self, hs: "HomeServer"):
        self.hs = hs
-        self.clock = hs.get_clock()
        self.store = hs.get_datastores().main
-        self._account_validity_handler = hs.get_account_validity_handler()
        self._storage_controllers = hs.get_storage_controllers()
-        self._macaroon_generator = hs.get_macaroon_generator()
-
-        self._track_appservice_user_ips = hs.config.appservice.track_appservice_user_ips
-        self._track_puppeted_user_ips = hs.config.api.track_puppeted_user_ips
-        self._force_tracing_for_users = hs.config.tracing.force_tracing_for_users

    async def check_user_in_room(
        self,
@@ -119,139 +97,49 @@ class Auth:
            errcode=Codes.NOT_JOINED,
        )

-    @cancellable
-    async def get_user_by_req(
-        self,
-        request: SynapseRequest,
-        allow_guest: bool = False,
-        allow_expired: bool = False,
-    ) -> Requester:
-        """Get a registered user's ID.
+    @trace
+    async def check_user_in_room_or_world_readable(
+        self, room_id: str, requester: Requester, allow_departed_users: bool = False
+    ) -> Tuple[str, Optional[str]]:
+        """Checks that the user is or was in the room or the room is world
+        readable. If it isn't then an exception is raised.

        Args:
-            request: An HTTP request with an access_token query parameter.
-            allow_guest: If False, will raise an AuthError if the user making the
-                request is a guest.
-            allow_expired: If True, allow the request through even if the account
-                is expired, or session token lifetime has ended. Note that
-                /login will deliver access tokens regardless of expiration.
+            room_id: room to check
+            user_id: user to check
+            allow_departed_users: if True, accept users that were previously
+                members but have now departed

        Returns:
-            Resolves to the requester
-        Raises:
-            InvalidClientCredentialsError if no user by that token exists or the token
-                is invalid.
-            AuthError if access is denied for the user in the access token
+            Resolves to the current membership of the user in the room and the
+            membership event ID of the user. If the user is not in the room and
+            never has been, then `(Membership.JOIN, None)` is returned.
        """
-        parent_span = active_span()
-        with start_active_span("get_user_by_req"):
-            requester = await self._wrapped_get_user_by_req(
-                request, allow_guest, allow_expired
-            )

-            if parent_span:
-                if requester.authenticated_entity in self._force_tracing_for_users:
-                    # request tracing is enabled for this user, so we need to force it
-                    # tracing on for the parent span (which will be the servlet span).
-                    #
-                    # It's too late for the get_user_by_req span to inherit the setting,
-                    # so we also force it on for that.
-                    force_tracing()
-                    force_tracing(parent_span)
-                parent_span.set_tag(
-                    "authenticated_entity", requester.authenticated_entity
-                )
-                parent_span.set_tag("user_id", requester.user.to_string())
-                if requester.device_id is not None:
-                    parent_span.set_tag("device_id", requester.device_id)
-                if requester.app_service is not None:
-                    parent_span.set_tag("appservice_id", requester.app_service.id)
-            return requester
-
-    @cancellable
-    async def _wrapped_get_user_by_req(
-        self,
-        request: SynapseRequest,
-        allow_guest: bool,
-        allow_expired: bool,
-    ) -> Requester:
-        """Helper for get_user_by_req
-
-        Once get_user_by_req has set up the opentracing span, this does the actual work.
-        """
        try:
-            ip_addr = request.getClientAddress().host
-            user_agent = get_request_user_agent(request)
-
-            access_token = self.get_access_token_from_request(request)
-
-            # First check if it could be a request from an appservice
-            requester = await self._get_appservice_user(request)
-            if not requester:
-                # If not, it should be from a regular user
-                requester = await self.get_user_by_access_token(
-                    access_token, allow_expired=allow_expired
-                )
-
-                # Deny the request if the user account has expired.
-                # This check is only done for regular users, not appservice ones.
-                if not allow_expired:
-                    if await self._account_validity_handler.is_user_expired(
-                        requester.user.to_string()
-                    ):
-                        # Raise the error if either an account validity module has determined
-                        # the account has expired, or the legacy account validity
-                        # implementation is enabled and determined the account has expired
-                        raise AuthError(
-                            403,
-                            "User account has expired",
-                            errcode=Codes.EXPIRED_ACCOUNT,
-                        )
-
-            if ip_addr and (
-                not requester.app_service or self._track_appservice_user_ips
+            # check_user_in_room will return the most recent membership
+            # event for the user if:
+            #  * The user is a non-guest user, and was ever in the room
+            #  * The user is a guest user, and has joined the room
+            # else it will throw.
+            return await self.check_user_in_room(
+                room_id, requester, allow_departed_users=allow_departed_users
+            )
+        except AuthError:
+            visibility = await self._storage_controllers.state.get_current_state_event(
+                room_id, EventTypes.RoomHistoryVisibility, ""
+            )
+            if (
+                visibility
+                and visibility.content.get("history_visibility")
+                == HistoryVisibility.WORLD_READABLE
            ):
-                # XXX(quenting): I'm 95% confident that we could skip setting the
-                # device_id to "dummy-device" for appservices, and that the only impact
-                # would be some rows which whould not deduplicate in the 'user_ips'
-                # table during the transition
-                recorded_device_id = (
-                    "dummy-device"
-                    if requester.device_id is None and requester.app_service is not None
-                    else requester.device_id
-                )
-                await self.store.insert_client_ip(
-                    user_id=requester.authenticated_entity,
-                    access_token=access_token,
-                    ip=ip_addr,
-                    user_agent=user_agent,
-                    device_id=recorded_device_id,
-                )
-
-                # Track also the puppeted user client IP if enabled and the user is puppeting
-                if (
-                    requester.user.to_string() != requester.authenticated_entity
-                    and self._track_puppeted_user_ips
-                ):
-                    await self.store.insert_client_ip(
-                        user_id=requester.user.to_string(),
-                        access_token=access_token,
-                        ip=ip_addr,
-                        user_agent=user_agent,
-                        device_id=requester.device_id,
-                    )
-
-            if requester.is_guest and not allow_guest:
-                raise AuthError(
-                    403,
-                    "Guest access not allowed",
-                    errcode=Codes.GUEST_ACCESS_FORBIDDEN,
-                )
-
-            request.requester = requester
-            return requester
-        except KeyError:
-            raise MissingClientTokenError()
+                return Membership.JOIN, None
+            raise AuthError(
+                403,
+                "User %r not in room %s, and room previews are disabled"
+                % (requester.user, room_id),
+            )

    async def validate_appservice_can_control_user_id(
        self, app_service: ApplicationService, user_id: str
@@ -284,184 +172,16 @@ class Auth:
                403, "Application service has not registered this user (%s)" % user_id
            )

-    @cancellable
-    async def _get_appservice_user(self, request: Request) -> Optional[Requester]:
-        """
-        Given a request, reads the request parameters to determine:
-        - whether it's an application service that's making this request
-        - what user the application service should be treated as controlling
-          (the user_id URI parameter allows an application service to masquerade
-          any applicable user in its namespace)
-        - what device the application service should be treated as controlling
-          (the device_id[^1] URI parameter allows an application service to masquerade
-          as any device that exists for the relevant user)
-
-        [^1] Unstable and provided by MSC3202.
-             Must use `org.matrix.msc3202.device_id` in place of `device_id` for now.
-
-        Returns:
-            the application service `Requester` of that request
-
-        Postconditions:
-        - The `app_service` field in the returned `Requester` is set
-        - The `user_id` field in the returned `Requester` is either the application
-          service sender or the controlled user set by the `user_id` URI parameter
-        - The returned application service is permitted to control the returned user ID.
-        - The returned device ID, if present, has been checked to be a valid device ID
-          for the returned user ID.
-        """
-        DEVICE_ID_ARG_NAME = b"org.matrix.msc3202.device_id"
-
-        app_service = self.store.get_app_service_by_token(
-            self.get_access_token_from_request(request)
-        )
-        if app_service is None:
-            return None
-
-        if app_service.ip_range_whitelist:
-            ip_address = IPAddress(request.getClientAddress().host)
-            if ip_address not in app_service.ip_range_whitelist:
-                return None
-
-        # This will always be set by the time Twisted calls us.
-        assert request.args is not None
-
-        if b"user_id" in request.args:
-            effective_user_id = request.args[b"user_id"][0].decode("utf8")
-            await self.validate_appservice_can_control_user_id(
-                app_service, effective_user_id
-            )
-        else:
-            effective_user_id = app_service.sender
-
-        effective_device_id: Optional[str] = None
-
-        if (
-            self.hs.config.experimental.msc3202_device_masquerading_enabled
-            and DEVICE_ID_ARG_NAME in request.args
-        ):
-            effective_device_id = request.args[DEVICE_ID_ARG_NAME][0].decode("utf8")
-            # We only just set this so it can't be None!
-            assert effective_device_id is not None
-            device_opt = await self.store.get_device(
-                effective_user_id, effective_device_id
-            )
-            if device_opt is None:
-                # For now, use 400 M_EXCLUSIVE if the device doesn't exist.
-                # This is an open thread of discussion on MSC3202 as of 2021-12-09.
-                raise AuthError(
-                    400,
-                    f"Application service trying to use a device that doesn't exist ('{effective_device_id}' for {effective_user_id})",
-                    Codes.EXCLUSIVE,
-                )
-
-        return create_requester(
-            effective_user_id, app_service=app_service, device_id=effective_device_id
-        )
-
-    async def get_user_by_access_token(
-        self,
-        token: str,
-        allow_expired: bool = False,
-    ) -> Requester:
-        """Validate access token and get user_id from it
-
-        Args:
-            token: The access token to get the user by
-            allow_expired: If False, raises an InvalidClientTokenError
-                if the token is expired
-
-        Raises:
-            InvalidClientTokenError if a user by that token exists, but the token is
-                expired
-            InvalidClientCredentialsError if no user by that token exists or the token
-                is invalid
-        """
-
-        # First look in the database to see if the access token is present
-        # as an opaque token.
-        user_info = await self.store.get_user_by_access_token(token)
-        if user_info:
-            valid_until_ms = user_info.valid_until_ms
-            if (
-                not allow_expired
-                and valid_until_ms is not None
-                and valid_until_ms < self.clock.time_msec()
-            ):
-                # there was a valid access token, but it has expired.
-                # soft-logout the user.
-                raise InvalidClientTokenError(
-                    msg="Access token has expired", soft_logout=True
-                )
-
-            # Mark the token as used. This is used to invalidate old refresh
-            # tokens after some time.
-            await self.store.mark_access_token_as_used(user_info.token_id)
-
-            requester = create_requester(
-                user_id=user_info.user_id,
-                access_token_id=user_info.token_id,
-                is_guest=user_info.is_guest,
-                shadow_banned=user_info.shadow_banned,
-                device_id=user_info.device_id,
-                authenticated_entity=user_info.token_owner,
-            )
-
-            return requester
-
-        # If the token isn't found in the database, then it could still be a
-        # macaroon for a guest, so we check that here.
-        try:
-            user_id = self._macaroon_generator.verify_guest_token(token)
-
-            # Guest access tokens are not stored in the database (there can
-            # only be one access token per guest, anyway).
-            #
-            # In order to prevent guest access tokens being used as regular
-            # user access tokens (and hence getting around the invalidation
-            # process), we look up the user id and check that it is indeed
-            # a guest user.
-            #
-            # It would of course be much easier to store guest access
-            # tokens in the database as well, but that would break existing
-            # guest tokens.
-            stored_user = await self.store.get_user_by_id(user_id)
-            if not stored_user:
-                raise InvalidClientTokenError("Unknown user_id %s" % user_id)
-            if not stored_user["is_guest"]:
-                raise InvalidClientTokenError(
-                    "Guest access token used for regular user"
-                )
-
-            return create_requester(
-                user_id=user_id,
-                is_guest=True,
-                # all guests get the same device id
-                device_id=GUEST_DEVICE_ID,
-                authenticated_entity=user_id,
-            )
-        except (
-            pymacaroons.exceptions.MacaroonException,
-            TypeError,
-            ValueError,
-        ) as e:
-            logger.warning(
-                "Invalid access token in auth: %s %s.",
-                type(e),
-                e,
-            )
-            raise InvalidClientTokenError("Invalid access token passed.")
-
    async def is_server_admin(self, requester: Requester) -> bool:
        """Check if the given user is a local server admin.

        Args:
-            requester: The user making the request, according to the access token.
+            requester: user to check

        Returns:
            True if the user is an admin
        """
-        return await self.store.is_server_admin(requester.user)
+        raise NotImplementedError()

    async def check_can_change_room_list(
        self, room_id: str, requester: Requester
@@ -470,8 +190,8 @@ class Auth:
        published room list.

        Args:
-            room_id: The room to check.
-            requester: The user making the request, according to the access token.
+            room_id
+            user
        """

        is_admin = await self.is_server_admin(requester)
@@ -518,7 +238,6 @@ class Auth:
        return bool(query_params) or bool(auth_headers)

    @staticmethod
-    @cancellable
    def get_access_token_from_request(request: Request) -> str:
        """Extracts the access_token from the request.

@@ -556,47 +275,77 @@ class Auth:

            return query_params[0].decode("ascii")

-    @trace
-    async def check_user_in_room_or_world_readable(
-        self, room_id: str, requester: Requester, allow_departed_users: bool = False
-    ) -> Tuple[str, Optional[str]]:
-        """Checks that the user is or was in the room or the room is world
-        readable. If it isn't then an exception is raised.
+    @cancellable
+    async def get_appservice_user(
+        self, request: Request, access_token: str
+    ) -> Optional[Requester]:
+        """
+        Given a request, reads the request parameters to determine:
+        - whether it's an application service that's making this request
+        - what user the application service should be treated as controlling
+          (the user_id URI parameter allows an application service to masquerade
+          any applicable user in its namespace)
+        - what device the application service should be treated as controlling
+          (the device_id[^1] URI parameter allows an application service to masquerade
+          as any device that exists for the relevant user)

-        Args:
-            room_id: The room to check.
-            requester: The user making the request, according to the access token.
-            allow_departed_users: If True, accept users that were previously
-                members but have now departed.
+        [^1] Unstable and provided by MSC3202.
+             Must use `org.matrix.msc3202.device_id` in place of `device_id` for now.

        Returns:
-            Resolves to the current membership of the user in the room and the
-            membership event ID of the user. If the user is not in the room and
-            never has been, then `(Membership.JOIN, None)` is returned.
-        """
+            the application service `Requester` of that request

-        try:
-            # check_user_in_room will return the most recent membership
-            # event for the user if:
-            #  * The user is a non-guest user, and was ever in the room
-            #  * The user is a guest user, and has joined the room
-            # else it will throw.
-            return await self.check_user_in_room(
-                room_id, requester, allow_departed_users=allow_departed_users
+        Postconditions:
+        - The `app_service` field in the returned `Requester` is set
+        - The `user_id` field in the returned `Requester` is either the application
+          service sender or the controlled user set by the `user_id` URI parameter
+        - The returned application service is permitted to control the returned user ID.
+        - The returned device ID, if present, has been checked to be a valid device ID
+          for the returned user ID.
+        """
+        DEVICE_ID_ARG_NAME = b"org.matrix.msc3202.device_id"
+
+        app_service = self.store.get_app_service_by_token(access_token)
+        if app_service is None:
+            return None
+
+        if app_service.ip_range_whitelist:
+            ip_address = IPAddress(request.getClientAddress().host)
+            if ip_address not in app_service.ip_range_whitelist:
+                return None
+
+        # This will always be set by the time Twisted calls us.
+        assert request.args is not None
+
+        if b"user_id" in request.args:
+            effective_user_id = request.args[b"user_id"][0].decode("utf8")
+            await self.validate_appservice_can_control_user_id(
+                app_service, effective_user_id
            )
-        except AuthError:
-            visibility = await self._storage_controllers.state.get_current_state_event(
-                room_id, EventTypes.RoomHistoryVisibility, ""
-            )
-            if (
-                visibility
-                and visibility.content.get("history_visibility")
-                == HistoryVisibility.WORLD_READABLE
-            ):
-                return Membership.JOIN, None
-            raise UnstableSpecAuthError(
-                403,
-                "User %s not in room %s, and room previews are disabled"
-                % (requester.user, room_id),
-                errcode=Codes.NOT_JOINED,
+        else:
+            effective_user_id = app_service.sender
+
+        effective_device_id: Optional[str] = None
+
+        if (
+            self.hs.config.experimental.msc3202_device_masquerading_enabled
+            and DEVICE_ID_ARG_NAME in request.args
+        ):
+            effective_device_id = request.args[DEVICE_ID_ARG_NAME][0].decode("utf8")
+            # We only just set this so it can't be None!
+            assert effective_device_id is not None
+            device_opt = await self.store.get_device(
+                effective_user_id, effective_device_id
            )
+            if device_opt is None:
+                # For now, use 400 M_EXCLUSIVE if the device doesn't exist.
+                # This is an open thread of discussion on MSC3202 as of 2021-12-09.
+                raise AuthError(
+                    400,
+                    f"Application service trying to use a device that doesn't exist ('{effective_device_id}' for {effective_user_id})",
+                    Codes.EXCLUSIVE,
+                )
+
+        return create_requester(
+            effective_user_id, app_service=app_service, device_id=effective_device_id
+        )
@@ -0,0 +1,304 @@
+# Copyright 2023 The Matrix.org Foundation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+from typing import TYPE_CHECKING
+
+import pymacaroons
+
+from synapse.api.errors import (
+    AuthError,
+    Codes,
+    InvalidClientTokenError,
+    MissingClientTokenError,
+)
+from synapse.http import get_request_user_agent
+from synapse.http.site import SynapseRequest
+from synapse.logging.opentracing import active_span, force_tracing, start_active_span
+from synapse.types import Requester, create_requester
+from synapse.util.cancellation import cancellable
+
+from . import GUEST_DEVICE_ID
+from .base import BaseAuth
+
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
+logger = logging.getLogger(__name__)
+
+
+class InternalAuth(BaseAuth):
+    """
+    This class contains functions for authenticating users of our client-server API.
+    """
+
+    def __init__(self, hs: "HomeServer"):
+        super().__init__(hs)
+        self.clock = hs.get_clock()
+        self._account_validity_handler = hs.get_account_validity_handler()
+        self._macaroon_generator = hs.get_macaroon_generator()
+
+        self._track_appservice_user_ips = hs.config.appservice.track_appservice_user_ips
+        self._track_puppeted_user_ips = hs.config.api.track_puppeted_user_ips
+        self._force_tracing_for_users = hs.config.tracing.force_tracing_for_users
+
+    @cancellable
+    async def get_user_by_req(
+        self,
+        request: SynapseRequest,
+        allow_guest: bool = False,
+        allow_expired: bool = False,
+        allow_locked: bool = False,
+    ) -> Requester:
+        """Get a registered user's ID.
+
+        Args:
+            request: An HTTP request with an access_token query parameter.
+            allow_guest: If False, will raise an AuthError if the user making the
+                request is a guest.
+            allow_expired: If True, allow the request through even if the account
+                is expired, or session token lifetime has ended. Note that
+                /login will deliver access tokens regardless of expiration.
+
+        Returns:
+            Resolves to the requester
+        Raises:
+            InvalidClientCredentialsError if no user by that token exists or the token
+                is invalid.
+            AuthError if access is denied for the user in the access token
+        """
+        parent_span = active_span()
+        with start_active_span("get_user_by_req"):
+            requester = await self._wrapped_get_user_by_req(
+                request, allow_guest, allow_expired, allow_locked
+            )
+
+            if parent_span:
+                if requester.authenticated_entity in self._force_tracing_for_users:
+                    # request tracing is enabled for this user, so we need to force it
+                    # tracing on for the parent span (which will be the servlet span).
+                    #
+                    # It's too late for the get_user_by_req span to inherit the setting,
+                    # so we also force it on for that.
+                    force_tracing()
+                    force_tracing(parent_span)
+                parent_span.set_tag(
+                    "authenticated_entity", requester.authenticated_entity
+                )
+                parent_span.set_tag("user_id", requester.user.to_string())
+                if requester.device_id is not None:
+                    parent_span.set_tag("device_id", requester.device_id)
+                if requester.app_service is not None:
+                    parent_span.set_tag("appservice_id", requester.app_service.id)
+            return requester
+
+    @cancellable
+    async def _wrapped_get_user_by_req(
+        self,
+        request: SynapseRequest,
+        allow_guest: bool,
+        allow_expired: bool,
+        allow_locked: bool,
+    ) -> Requester:
+        """Helper for get_user_by_req
+
+        Once get_user_by_req has set up the opentracing span, this does the actual work.
+        """
+        try:
+            ip_addr = request.getClientAddress().host
+            user_agent = get_request_user_agent(request)
+
+            access_token = self.get_access_token_from_request(request)
+
+            # First check if it could be a request from an appservice
+            requester = await self.get_appservice_user(request, access_token)
+            if not requester:
+                # If not, it should be from a regular user
+                requester = await self.get_user_by_access_token(
+                    access_token, allow_expired=allow_expired
+                )
+
+                # Deny the request if the user account is locked.
+                if not allow_locked and await self.store.get_user_locked_status(
+                    requester.user.to_string()
+                ):
+                    raise AuthError(
+                        401,
+                        "User account has been locked",
+                        errcode=Codes.USER_LOCKED,
+                        additional_fields={"soft_logout": True},
+                    )
+
+                # Deny the request if the user account has expired.
+                # This check is only done for regular users, not appservice ones.
+                if not allow_expired:
+                    if await self._account_validity_handler.is_user_expired(
+                        requester.user.to_string()
+                    ):
+                        # Raise the error if either an account validity module has determined
+                        # the account has expired, or the legacy account validity
+                        # implementation is enabled and determined the account has expired
+                        raise AuthError(
+                            403,
+                            "User account has expired",
+                            errcode=Codes.EXPIRED_ACCOUNT,
+                        )
+
+            if ip_addr and (
+                not requester.app_service or self._track_appservice_user_ips
+            ):
+                # XXX(quenting): I'm 95% confident that we could skip setting the
+                # device_id to "dummy-device" for appservices, and that the only impact
+                # would be some rows which whould not deduplicate in the 'user_ips'
+                # table during the transition
+                recorded_device_id = (
+                    "dummy-device"
+                    if requester.device_id is None and requester.app_service is not None
+                    else requester.device_id
+                )
+                await self.store.insert_client_ip(
+                    user_id=requester.authenticated_entity,
+                    access_token=access_token,
+                    ip=ip_addr,
+                    user_agent=user_agent,
+                    device_id=recorded_device_id,
+                )
+
+                # Track also the puppeted user client IP if enabled and the user is puppeting
+                if (
+                    requester.user.to_string() != requester.authenticated_entity
+                    and self._track_puppeted_user_ips
+                ):
+                    await self.store.insert_client_ip(
+                        user_id=requester.user.to_string(),
+                        access_token=access_token,
+                        ip=ip_addr,
+                        user_agent=user_agent,
+                        device_id=requester.device_id,
+                    )
+
+            if requester.is_guest and not allow_guest:
+                raise AuthError(
+                    403,
+                    "Guest access not allowed",
+                    errcode=Codes.GUEST_ACCESS_FORBIDDEN,
+                )
+
+            request.requester = requester
+            return requester
+        except KeyError:
+            raise MissingClientTokenError()
+
+    async def get_user_by_access_token(
+        self,
+        token: str,
+        allow_expired: bool = False,
+    ) -> Requester:
+        """Validate access token and get user_id from it
+
+        Args:
+            token: The access token to get the user by
+            allow_expired: If False, raises an InvalidClientTokenError
+                if the token is expired
+
+        Raises:
+            InvalidClientTokenError if a user by that token exists, but the token is
+                expired
+            InvalidClientCredentialsError if no user by that token exists or the token
+                is invalid
+        """
+
+        # First look in the database to see if the access token is present
+        # as an opaque token.
+        user_info = await self.store.get_user_by_access_token(token)
+        if user_info:
+            valid_until_ms = user_info.valid_until_ms
+            if (
+                not allow_expired
+                and valid_until_ms is not None
+                and valid_until_ms < self.clock.time_msec()
+            ):
+                # there was a valid access token, but it has expired.
+                # soft-logout the user.
+                raise InvalidClientTokenError(
+                    msg="Access token has expired", soft_logout=True
+                )
+
+            # Mark the token as used. This is used to invalidate old refresh
+            # tokens after some time.
+            await self.store.mark_access_token_as_used(user_info.token_id)
+
+            requester = create_requester(
+                user_id=user_info.user_id,
+                access_token_id=user_info.token_id,
+                is_guest=user_info.is_guest,
+                shadow_banned=user_info.shadow_banned,
+                device_id=user_info.device_id,
+                authenticated_entity=user_info.token_owner,
+            )
+
+            return requester
+
+        # If the token isn't found in the database, then it could still be a
+        # macaroon for a guest, so we check that here.
+        try:
+            user_id = self._macaroon_generator.verify_guest_token(token)
+
+            # Guest access tokens are not stored in the database (there can
+            # only be one access token per guest, anyway).
+            #
+            # In order to prevent guest access tokens being used as regular
+            # user access tokens (and hence getting around the invalidation
+            # process), we look up the user id and check that it is indeed
+            # a guest user.
+            #
+            # It would of course be much easier to store guest access
+            # tokens in the database as well, but that would break existing
+            # guest tokens.
+            stored_user = await self.store.get_user_by_id(user_id)
+            if not stored_user:
+                raise InvalidClientTokenError("Unknown user_id %s" % user_id)
+            if not stored_user["is_guest"]:
+                raise InvalidClientTokenError(
+                    "Guest access token used for regular user"
+                )
+
+            return create_requester(
+                user_id=user_id,
+                is_guest=True,
+                # all guests get the same device id
+                device_id=GUEST_DEVICE_ID,
+                authenticated_entity=user_id,
+            )
+        except (
+            pymacaroons.exceptions.MacaroonException,
+            TypeError,
+            ValueError,
+        ) as e:
+            logger.warning(
+                "Invalid access token in auth: %s %s.",
+                type(e),
+                e,
+            )
+            raise InvalidClientTokenError("Invalid access token passed.")
+
+    async def is_server_admin(self, requester: Requester) -> bool:
+        """Check if the given user is a local server admin.
+
+        Args:
+            requester: The user making the request, according to the access token.
+
+        Returns:
+            True if the user is an admin
+        """
+        return await self.store.is_server_admin(requester.user)
@@ -0,0 +1,401 @@
+# Copyright 2023 The Matrix.org Foundation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+from typing import TYPE_CHECKING, Any, Dict, List, Optional
+from urllib.parse import urlencode
+
+from authlib.oauth2 import ClientAuth
+from authlib.oauth2.auth import encode_client_secret_basic, encode_client_secret_post
+from authlib.oauth2.rfc7523 import ClientSecretJWT, PrivateKeyJWT, private_key_jwt_sign
+from authlib.oauth2.rfc7662 import IntrospectionToken
+from authlib.oidc.discovery import OpenIDProviderMetadata, get_well_known_url
+
+from twisted.web.client import readBody
+from twisted.web.http_headers import Headers
+
+from synapse.api.auth.base import BaseAuth
+from synapse.api.errors import (
+    AuthError,
+    Codes,
+    HttpResponseException,
+    InvalidClientTokenError,
+    OAuthInsufficientScopeError,
+    StoreError,
+    SynapseError,
+)
+from synapse.http.site import SynapseRequest
+from synapse.logging.context import make_deferred_yieldable
+from synapse.types import Requester, UserID, create_requester
+from synapse.util import json_decoder
+from synapse.util.caches.cached_call import RetryOnExceptionCachedCall
+from synapse.util.caches.expiringcache import ExpiringCache
+
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
+logger = logging.getLogger(__name__)
+
+# Scope as defined by MSC2967
+# https://github.com/matrix-org/matrix-spec-proposals/pull/2967
+SCOPE_MATRIX_API = "urn:matrix:org.matrix.msc2967.client:api:*"
+SCOPE_MATRIX_GUEST = "urn:matrix:org.matrix.msc2967.client:api:guest"
+SCOPE_MATRIX_DEVICE_PREFIX = "urn:matrix:org.matrix.msc2967.client:device:"
+
+# Scope which allows access to the Synapse admin API
+SCOPE_SYNAPSE_ADMIN = "urn:synapse:admin:*"
+
+
+def scope_to_list(scope: str) -> List[str]:
+    """Convert a scope string to a list of scope tokens"""
+    return scope.strip().split(" ")
+
+
+class PrivateKeyJWTWithKid(PrivateKeyJWT):  # type: ignore[misc]
+    """An implementation of the private_key_jwt client auth method that includes a kid header.
+
+    This is needed because some providers (Keycloak) require the kid header to figure
+    out which key to use to verify the signature.
+    """
+
+    def sign(self, auth: Any, token_endpoint: str) -> bytes:
+        return private_key_jwt_sign(
+            auth.client_secret,
+            client_id=auth.client_id,
+            token_endpoint=token_endpoint,
+            claims=self.claims,
+            header={"kid": auth.client_secret["kid"]},
+        )
+
+
+class MSC3861DelegatedAuth(BaseAuth):
+    AUTH_METHODS = {
+        "client_secret_post": encode_client_secret_post,
+        "client_secret_basic": encode_client_secret_basic,
+        "client_secret_jwt": ClientSecretJWT(),
+        "private_key_jwt": PrivateKeyJWTWithKid(),
+    }
+
+    EXTERNAL_ID_PROVIDER = "oauth-delegated"
+
+    def __init__(self, hs: "HomeServer"):
+        super().__init__(hs)
+
+        self._config = hs.config.experimental.msc3861
+        auth_method = MSC3861DelegatedAuth.AUTH_METHODS.get(
+            self._config.client_auth_method.value, None
+        )
+        # Those assertions are already checked when parsing the config
+        assert self._config.enabled, "OAuth delegation is not enabled"
+        assert self._config.issuer, "No issuer provided"
+        assert self._config.client_id, "No client_id provided"
+        assert auth_method is not None, "Invalid client_auth_method provided"
+
+        self._http_client = hs.get_proxied_http_client()
+        self._hostname = hs.hostname
+        self._admin_token = self._config.admin_token
+
+        self._issuer_metadata = RetryOnExceptionCachedCall(self._load_metadata)
+
+        self._clock = hs.get_clock()
+        self._token_cache: ExpiringCache[str, IntrospectionToken] = ExpiringCache(
+            cache_name="introspection_token_cache",
+            clock=self._clock,
+            max_len=10000,
+            expiry_ms=5 * 60 * 1000,
+        )
+
+        if isinstance(auth_method, PrivateKeyJWTWithKid):
+            # Use the JWK as the client secret when using the private_key_jwt method
+            assert self._config.jwk, "No JWK provided"
+            self._client_auth = ClientAuth(
+                self._config.client_id, self._config.jwk, auth_method
+            )
+        else:
+            # Else use the client secret
+            assert self._config.client_secret, "No client_secret provided"
+            self._client_auth = ClientAuth(
+                self._config.client_id, self._config.client_secret, auth_method
+            )
+
+    async def _load_metadata(self) -> OpenIDProviderMetadata:
+        if self._config.issuer_metadata is not None:
+            return OpenIDProviderMetadata(**self._config.issuer_metadata)
+        url = get_well_known_url(self._config.issuer, external=True)
+        response = await self._http_client.get_json(url)
+        metadata = OpenIDProviderMetadata(**response)
+        # metadata.validate_introspection_endpoint()
+        return metadata
+
+    async def _introspect_token(self, token: str) -> IntrospectionToken:
+        """
+        Send a token to the introspection endpoint and returns the introspection response
+
+        Parameters:
+            token: The token to introspect
+
+        Raises:
+            HttpResponseException: If the introspection endpoint returns a non-2xx response
+            ValueError: If the introspection endpoint returns an invalid JSON response
+            JSONDecodeError: If the introspection endpoint returns a non-JSON response
+            Exception: If the HTTP request fails
+
+        Returns:
+            The introspection response
+        """
+        # check the cache before doing a request
+        introspection_token = self._token_cache.get(token, None)
+
+        if introspection_token:
+            # check the expiration field of the token (if it exists)
+            exp = introspection_token.get("exp", None)
+            if exp:
+                time_now = self._clock.time()
+                expired = time_now > exp
+                if not expired:
+                    return introspection_token
+            else:
+                return introspection_token
+
+        metadata = await self._issuer_metadata.get()
+        introspection_endpoint = metadata.get("introspection_endpoint")
+        raw_headers: Dict[str, str] = {
+            "Content-Type": "application/x-www-form-urlencoded",
+            "User-Agent": str(self._http_client.user_agent, "utf-8"),
+            "Accept": "application/json",
+        }
+
+        args = {"token": token, "token_type_hint": "access_token"}
+        body = urlencode(args, True)
+
+        # Fill the body/headers with credentials
+        uri, raw_headers, body = self._client_auth.prepare(
+            method="POST",
+            uri=introspection_endpoint,
+            headers=raw_headers,
+            body=body,
+        )
+        headers = Headers({k: [v] for (k, v) in raw_headers.items()})
+
+        # Do the actual request
+        # We're not using the SimpleHttpClient util methods as we don't want to
+        # check the HTTP status code, and we do the body encoding ourselves.
+        response = await self._http_client.request(
+            method="POST",
+            uri=uri,
+            data=body.encode("utf-8"),
+            headers=headers,
+        )
+
+        resp_body = await make_deferred_yieldable(readBody(response))
+
+        if response.code < 200 or response.code >= 300:
+            raise HttpResponseException(
+                response.code,
+                response.phrase.decode("ascii", errors="replace"),
+                resp_body,
+            )
+
+        resp = json_decoder.decode(resp_body.decode("utf-8"))
+
+        if not isinstance(resp, dict):
+            raise ValueError(
+                "The introspection endpoint returned an invalid JSON response."
+            )
+
+        expiration = resp.get("exp", None)
+        if expiration:
+            if self._clock.time() > expiration:
+                raise InvalidClientTokenError("Token is expired.")
+
+        introspection_token = IntrospectionToken(**resp)
+
+        # add token to cache
+        self._token_cache[token] = introspection_token
+
+        return introspection_token
+
+    async def is_server_admin(self, requester: Requester) -> bool:
+        return "urn:synapse:admin:*" in requester.scope
+
+    async def get_user_by_req(
+        self,
+        request: SynapseRequest,
+        allow_guest: bool = False,
+        allow_expired: bool = False,
+        allow_locked: bool = False,
+    ) -> Requester:
+        access_token = self.get_access_token_from_request(request)
+
+        requester = await self.get_appservice_user(request, access_token)
+        if not requester:
+            # TODO: we probably want to assert the allow_guest inside this call
+            # so that we don't provision the user if they don't have enough permission:
+            requester = await self.get_user_by_access_token(access_token, allow_expired)
+
+            # Deny the request if the user account is locked.
+            if not allow_locked and await self.store.get_user_locked_status(
+                requester.user.to_string()
+            ):
+                raise AuthError(
+                    401,
+                    "User account has been locked",
+                    errcode=Codes.USER_LOCKED,
+                    additional_fields={"soft_logout": True},
+                )
+
+        if not allow_guest and requester.is_guest:
+            raise OAuthInsufficientScopeError([SCOPE_MATRIX_API])
+
+        request.requester = requester
+
+        return requester
+
+    async def get_user_by_access_token(
+        self,
+        token: str,
+        allow_expired: bool = False,
+    ) -> Requester:
+        if self._admin_token is not None and token == self._admin_token:
+            # XXX: This is a temporary solution so that the admin API can be called by
+            # the OIDC provider. This will be removed once we have OIDC client
+            # credentials grant support in matrix-authentication-service.
+            logging.info("Admin toked used")
+            # XXX: that user doesn't exist and won't be provisioned.
+            # This is mostly fine for admin calls, but we should also think about doing
+            # requesters without a user_id.
+            admin_user = UserID("__oidc_admin", self._hostname)
+            return create_requester(
+                user_id=admin_user,
+                scope=["urn:synapse:admin:*"],
+            )
+
+        try:
+            introspection_result = await self._introspect_token(token)
+        except Exception:
+            logger.exception("Failed to introspect token")
+            raise SynapseError(503, "Unable to introspect the access token")
+
+        logger.info(f"Introspection result: {introspection_result!r}")
+
+        # TODO: introspection verification should be more extensive, especially:
+        #   - verify the audience
+        if not introspection_result.get("active"):
+            raise InvalidClientTokenError("Token is not active")
+
+        # Let's look at the scope
+        scope: List[str] = scope_to_list(introspection_result.get("scope", ""))
+
+        # Determine type of user based on presence of particular scopes
+        has_user_scope = SCOPE_MATRIX_API in scope
+        has_guest_scope = SCOPE_MATRIX_GUEST in scope
+
+        if not has_user_scope and not has_guest_scope:
+            raise InvalidClientTokenError("No scope in token granting user rights")
+
+        # Match via the sub claim
+        sub: Optional[str] = introspection_result.get("sub")
+        if sub is None:
+            raise InvalidClientTokenError(
+                "Invalid sub claim in the introspection result"
+            )
+
+        user_id_str = await self.store.get_user_by_external_id(
+            MSC3861DelegatedAuth.EXTERNAL_ID_PROVIDER, sub
+        )
+        if user_id_str is None:
+            # If we could not find a user via the external_id, it either does not exist,
+            # or the external_id was never recorded
+
+            # TODO: claim mapping should be configurable
+            username: Optional[str] = introspection_result.get("username")
+            if username is None or not isinstance(username, str):
+                raise AuthError(
+                    500,
+                    "Invalid username claim in the introspection result",
+                )
+            user_id = UserID(username, self._hostname)
+
+            # First try to find a user from the username claim
+            user_info = await self.store.get_userinfo_by_id(user_id=user_id.to_string())
+            if user_info is None:
+                # If the user does not exist, we should create it on the fly
+                # TODO: we could use SCIM to provision users ahead of time and listen
+                # for SCIM SET events if those ever become standard:
+                # https://datatracker.ietf.org/doc/html/draft-hunt-scim-notify-00
+
+                # TODO: claim mapping should be configurable
+                # If present, use the name claim as the displayname
+                name: Optional[str] = introspection_result.get("name")
+
+                await self.store.register_user(
+                    user_id=user_id.to_string(), create_profile_with_displayname=name
+                )
+
+            # And record the sub as external_id
+            await self.store.record_user_external_id(
+                MSC3861DelegatedAuth.EXTERNAL_ID_PROVIDER, sub, user_id.to_string()
+            )
+        else:
+            user_id = UserID.from_string(user_id_str)
+
+        # Find device_ids in scope
+        # We only allow a single device_id in the scope, so we find them all in the
+        # scope list, and raise if there are more than one. The OIDC server should be
+        # the one enforcing valid scopes, so we raise a 500 if we find an invalid scope.
+        device_ids = [
+            tok[len(SCOPE_MATRIX_DEVICE_PREFIX) :]
+            for tok in scope
+            if tok.startswith(SCOPE_MATRIX_DEVICE_PREFIX)
+        ]
+
+        if len(device_ids) > 1:
+            raise AuthError(
+                500,
+                "Multiple device IDs in scope",
+            )
+
+        device_id = device_ids[0] if device_ids else None
+        if device_id is not None:
+            # Sanity check the device_id
+            if len(device_id) > 255 or len(device_id) < 1:
+                raise AuthError(
+                    500,
+                    "Invalid device ID in scope",
+                )
+
+            # Create the device on the fly if it does not exist
+            try:
+                await self.store.get_device(
+                    user_id=user_id.to_string(), device_id=device_id
+                )
+            except StoreError:
+                await self.store.store_device(
+                    user_id=user_id.to_string(),
+                    device_id=device_id,
+                    initial_device_display_name="OIDC-native client",
+                )
+
+        # TODO: there is a few things missing in the requester here, which still need
+        # to be figured out, like:
+        #   - impersonation, with the `authenticated_entity`, which is used for
+        #     rate-limiting, MAU limits, etc.
+        #   - shadow-banning, with the `shadow_banned` flag
+        #   - a proper solution for appservices, which still needs to be figured out in
+        #     the context of MSC3861
+        return create_requester(
+            user_id=user_id,
+            device_id=device_id,
+            scope=scope,
+            is_guest=(has_guest_scope and not has_user_scope),
+        )
@@ -18,8 +18,7 @@
 """Contains constants from the specification."""

 import enum
-
-from typing_extensions import Final
+from typing import Final

 # the max size of a (canonical-json-encoded) event
 MAX_PDU_SIZE = 65536
@@ -123,10 +122,6 @@ class EventTypes:
    SpaceChild: Final = "m.space.child"
    SpaceParent: Final = "m.space.parent"

-    MSC2716_INSERTION: Final = "org.matrix.msc2716.insertion"
-    MSC2716_BATCH: Final = "org.matrix.msc2716.batch"
-    MSC2716_MARKER: Final = "org.matrix.msc2716.marker"
-
    Reaction: Final = "m.reaction"


@@ -222,21 +217,11 @@ class EventContentFields:
    # Used in m.room.guest_access events.
    GUEST_ACCESS: Final = "guest_access"

-    # Used on normal messages to indicate they were historically imported after the fact
-    MSC2716_HISTORICAL: Final = "org.matrix.msc2716.historical"
-    # For "insertion" events to indicate what the next batch ID should be in
-    # order to connect to it
-    MSC2716_NEXT_BATCH_ID: Final = "next_batch_id"
-    # Used on "batch" events to indicate which insertion event it connects to
-    MSC2716_BATCH_ID: Final = "batch_id"
-    # For "marker" events
-    MSC2716_INSERTION_EVENT_REFERENCE: Final = "insertion_event_reference"
-
    # The authorising user for joining a restricted room.
    AUTHORISING_USER: Final = "join_authorised_via_users_server"

    # Use for mentioning users.
-    MSC3952_MENTIONS: Final = "org.matrix.msc3952.mentions"
+    MENTIONS: Final = "m.mentions"

    # an unspecced field added to to-device messages to identify them uniquely-ish
    TO_DEVICE_MSGID: Final = "org.matrix.msgid"
@@ -80,6 +80,8 @@ class Codes(str, Enum):
    WEAK_PASSWORD = "M_WEAK_PASSWORD"
    INVALID_SIGNATURE = "M_INVALID_SIGNATURE"
    USER_DEACTIVATED = "M_USER_DEACTIVATED"
+    # USER_LOCKED = "M_USER_LOCKED"
+    USER_LOCKED = "ORG_MATRIX_MSC3939_USER_LOCKED"

    # Part of MSC3848
    # https://github.com/matrix-org/matrix-spec-proposals/pull/3848
@@ -119,14 +121,20 @@ class Codes(str, Enum):


 class CodeMessageException(RuntimeError):
-    """An exception with integer code and message string attributes.
+    """An exception with integer code, a message string attributes and optional headers.

    Attributes:
        code: HTTP error code
        msg: string describing the error
+        headers: optional response headers to send
    """

-    def __init__(self, code: Union[int, HTTPStatus], msg: str):
+    def __init__(
+        self,
+        code: Union[int, HTTPStatus],
+        msg: str,
+        headers: Optional[Dict[str, str]] = None,
+    ):
        super().__init__("%d: %s" % (code, msg))

        # Some calls to this method pass instances of http.HTTPStatus for `code`.
@@ -137,6 +145,7 @@ class CodeMessageException(RuntimeError):
        # To eliminate this behaviour, we convert them to their integer equivalents here.
        self.code = int(code)
        self.msg = msg
+        self.headers = headers


 class RedirectException(CodeMessageException):
@@ -182,6 +191,7 @@ class SynapseError(CodeMessageException):
        msg: str,
        errcode: str = Codes.UNKNOWN,
        additional_fields: Optional[Dict] = None,
+        headers: Optional[Dict[str, str]] = None,
    ):
        """Constructs a synapse error.

@@ -190,7 +200,7 @@ class SynapseError(CodeMessageException):
            msg: The human-readable error message.
            errcode: The matrix error code e.g 'M_FORBIDDEN'
        """
-        super().__init__(code, msg)
+        super().__init__(code, msg, headers)
        self.errcode = errcode
        if additional_fields is None:
            self._additional_fields: Dict = {}
@@ -209,6 +219,13 @@ class InvalidAPICallError(SynapseError):
        super().__init__(HTTPStatus.BAD_REQUEST, msg, Codes.BAD_JSON)


+class InvalidProxyCredentialsError(SynapseError):
+    """Error raised when the proxy credentials are invalid."""
+
+    def __init__(self, msg: str, errcode: str = Codes.UNKNOWN):
+        super().__init__(401, msg, errcode)
+
+
 class ProxiedRequestError(SynapseError):
    """An error from a general matrix endpoint, eg. from a proxied Matrix API call.

@@ -335,6 +352,20 @@ class AuthError(SynapseError):
        super().__init__(code, msg, errcode, additional_fields)


+class OAuthInsufficientScopeError(SynapseError):
+    """An error raised when the caller does not have sufficient scope to perform the requested action"""
+
+    def __init__(
+        self,
+        required_scopes: List[str],
+    ):
+        headers = {
+            "WWW-Authenticate": 'Bearer error="insufficient_scope", scope="%s"'
+            % (" ".join(required_scopes))
+        }
+        super().__init__(401, "Insufficient scope", Codes.FORBIDDEN, None, headers)
+
+
 class UnstableSpecAuthError(AuthError):
    """An error raised when a new error code is being proposed to replace a previous one.
    This error will return a "org.matrix.unstable.errcode" property with the new error code,
@@ -152,9 +152,9 @@ class Filtering:
        self.DEFAULT_FILTER_COLLECTION = FilterCollection(hs, {})

    async def get_user_filter(
-        self, user_localpart: str, filter_id: Union[int, str]
+        self, user_id: UserID, filter_id: Union[int, str]
    ) -> "FilterCollection":
-        result = await self.store.get_user_filter(user_localpart, filter_id)
+        result = await self.store.get_user_filter(user_id, filter_id)
        return FilterCollection(self._hs, result)

    def add_user_filter(self, user_id: UserID, user_filter: JsonDict) -> Awaitable[int]:
@@ -78,41 +78,29 @@ class RoomVersion:
    # MSC2209: Check 'notifications' key while verifying
    # m.room.power_levels auth rules.
    limit_notifications_power_levels: bool
-    # MSC2175: No longer include the creator in m.room.create events.
-    msc2175_implicit_room_creator: bool
-    # MSC2174/MSC2176: Apply updated redaction rules algorithm, move redacts to
-    # content property.
-    msc2176_redaction_rules: bool
-    # MSC3083: Support the 'restricted' join_rule.
-    msc3083_join_rules: bool
-    # MSC3375: Support for the proper redaction rules for MSC3083. This mustn't
-    #          be enabled if MSC3083 is not.
-    msc3375_redaction_rules: bool
-    # MSC2403: Allows join_rules to be set to 'knock', changes auth rules to allow sending
-    # m.room.membership event with membership 'knock'.
-    msc2403_knocking: bool
-    # MSC2716: Adds m.room.power_levels -> content.historical field to control
-    # whether "insertion", "chunk", "marker" events can be sent
-    msc2716_historical: bool
-    # MSC2716: Adds support for redacting "insertion", "chunk", and "marker" events
-    msc2716_redactions: bool
+    # No longer include the creator in m.room.create events.
+    implicit_room_creator: bool
+    # Apply updated redaction rules algorithm from room version 11.
+    updated_redaction_rules: bool
+    # Support the 'restricted' join rule.
+    restricted_join_rule: bool
+    # Support for the proper redaction rules for the restricted join rule. This requires
+    # restricted_join_rule to be enabled.
+    restricted_join_rule_fix: bool
+    # Support the 'knock' join rule.
+    knock_join_rule: bool
    # MSC3389: Protect relation information from redaction.
    msc3389_relation_redactions: bool
-    # MSC3787: Adds support for a `knock_restricted` join rule, mixing concepts of
-    # knocks and restricted join rules into the same join condition.
-    msc3787_knock_restricted_join_rule: bool
-    # MSC3667: Enforce integer power levels
-    msc3667_int_only_power_levels: bool
-    # MSC3821: Do not redact the third_party_invite content field for membership events.
-    msc3821_redaction_rules: bool
+    # Support the 'knock_restricted' join rule.
+    knock_restricted_join_rule: bool
+    # Enforce integer power levels
+    enforce_int_power_levels: bool
    # MSC3931: Adds a push rule condition for "room version feature flags", making
    # some push rules room version dependent. Note that adding a flag to this list
    # is not enough to mark it "supported": the push rule evaluator also needs to
    # support the flag. Unknown flags are ignored by the evaluator, making conditions
    # fail if used.
    msc3931_push_features: Tuple[str, ...]  # values from PushRuleRoomFlag
-    # MSC3989: Redact the origin field.
-    msc3989_redaction_rules: bool


 class RoomVersions:
@@ -125,19 +113,15 @@ class RoomVersions:
        special_case_aliases_auth=True,
        strict_canonicaljson=False,
        limit_notifications_power_levels=False,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=False,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=False,
+        restricted_join_rule_fix=False,
+        knock_join_rule=False,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V2 = RoomVersion(
        "2",
@@ -148,19 +132,15 @@ class RoomVersions:
        special_case_aliases_auth=True,
        strict_canonicaljson=False,
        limit_notifications_power_levels=False,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=False,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=False,
+        restricted_join_rule_fix=False,
+        knock_join_rule=False,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V3 = RoomVersion(
        "3",
@@ -171,19 +151,15 @@ class RoomVersions:
        special_case_aliases_auth=True,
        strict_canonicaljson=False,
        limit_notifications_power_levels=False,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=False,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=False,
+        restricted_join_rule_fix=False,
+        knock_join_rule=False,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V4 = RoomVersion(
        "4",
@@ -194,19 +170,15 @@ class RoomVersions:
        special_case_aliases_auth=True,
        strict_canonicaljson=False,
        limit_notifications_power_levels=False,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=False,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=False,
+        restricted_join_rule_fix=False,
+        knock_join_rule=False,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V5 = RoomVersion(
        "5",
@@ -217,19 +189,15 @@ class RoomVersions:
        special_case_aliases_auth=True,
        strict_canonicaljson=False,
        limit_notifications_power_levels=False,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=False,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=False,
+        restricted_join_rule_fix=False,
+        knock_join_rule=False,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V6 = RoomVersion(
        "6",
@@ -240,42 +208,15 @@ class RoomVersions:
        special_case_aliases_auth=False,
        strict_canonicaljson=True,
        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=False,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=False,
+        restricted_join_rule_fix=False,
+        knock_join_rule=False,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
-    )
-    MSC2176 = RoomVersion(
-        "org.matrix.msc2176",
-        RoomDisposition.UNSTABLE,
-        EventFormatVersions.ROOM_V4_PLUS,
-        StateResolutionVersions.V2,
-        enforce_key_validity=True,
-        special_case_aliases_auth=False,
-        strict_canonicaljson=True,
-        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=True,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=False,
-        msc2716_historical=False,
-        msc2716_redactions=False,
-        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
-        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V7 = RoomVersion(
        "7",
@@ -286,19 +227,15 @@ class RoomVersions:
        special_case_aliases_auth=False,
        strict_canonicaljson=True,
        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=False,
+        restricted_join_rule_fix=False,
+        knock_join_rule=True,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V8 = RoomVersion(
        "8",
@@ -309,19 +246,15 @@ class RoomVersions:
        special_case_aliases_auth=False,
        strict_canonicaljson=True,
        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=True,
+        restricted_join_rule_fix=False,
+        knock_join_rule=True,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V9 = RoomVersion(
        "9",
@@ -332,65 +265,15 @@ class RoomVersions:
        special_case_aliases_auth=False,
        strict_canonicaljson=True,
        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=True,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=True,
+        restricted_join_rule_fix=True,
+        knock_join_rule=True,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=False,
+        enforce_int_power_levels=False,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
-    )
-    MSC3787 = RoomVersion(
-        "org.matrix.msc3787",
-        RoomDisposition.UNSTABLE,
-        EventFormatVersions.ROOM_V4_PLUS,
-        StateResolutionVersions.V2,
-        enforce_key_validity=True,
-        special_case_aliases_auth=False,
-        strict_canonicaljson=True,
-        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=True,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
-        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=True,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
-        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
-    )
-    MSC3821 = RoomVersion(
-        "org.matrix.msc3821.opt1",
-        RoomDisposition.UNSTABLE,
-        EventFormatVersions.ROOM_V4_PLUS,
-        StateResolutionVersions.V2,
-        enforce_key_validity=True,
-        special_case_aliases_auth=False,
-        strict_canonicaljson=True,
-        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=True,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
-        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=True,
-        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    V10 = RoomVersion(
        "10",
@@ -401,42 +284,15 @@ class RoomVersions:
        special_case_aliases_auth=False,
        strict_canonicaljson=True,
        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=True,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=True,
+        restricted_join_rule_fix=True,
+        knock_join_rule=True,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=True,
-        msc3667_int_only_power_levels=True,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=True,
+        enforce_int_power_levels=True,
        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
-    )
-    MSC2716v4 = RoomVersion(
-        "org.matrix.msc2716v4",
-        RoomDisposition.UNSTABLE,
-        EventFormatVersions.ROOM_V4_PLUS,
-        StateResolutionVersions.V2,
-        enforce_key_validity=True,
-        special_case_aliases_auth=False,
-        strict_canonicaljson=True,
-        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=False,
-        msc3375_redaction_rules=False,
-        msc2403_knocking=True,
-        msc2716_historical=True,
-        msc2716_redactions=True,
-        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=False,
-        msc3667_int_only_power_levels=False,
-        msc3821_redaction_rules=False,
-        msc3931_push_features=(),
-        msc3989_redaction_rules=False,
    )
    MSC1767v10 = RoomVersion(
        # MSC1767 (Extensible Events) based on room version "10"
@@ -448,66 +304,34 @@ class RoomVersions:
        special_case_aliases_auth=False,
        strict_canonicaljson=True,
        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=True,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=False,
+        updated_redaction_rules=False,
+        restricted_join_rule=True,
+        restricted_join_rule_fix=True,
+        knock_join_rule=True,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=True,
-        msc3667_int_only_power_levels=True,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=True,
+        enforce_int_power_levels=True,
        msc3931_push_features=(PushRuleRoomFlag.EXTENSIBLE_EVENTS,),
-        msc3989_redaction_rules=False,
    )
-    MSC3989 = RoomVersion(
-        "org.matrix.msc3989",
-        RoomDisposition.UNSTABLE,
+    V11 = RoomVersion(
+        "11",
+        RoomDisposition.STABLE,
        EventFormatVersions.ROOM_V4_PLUS,
        StateResolutionVersions.V2,
        enforce_key_validity=True,
        special_case_aliases_auth=False,
        strict_canonicaljson=True,
        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=False,
-        msc2176_redaction_rules=False,
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=True,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
+        implicit_room_creator=True,  # Used by MSC3820
+        updated_redaction_rules=True,  # Used by MSC3820
+        restricted_join_rule=True,
+        restricted_join_rule_fix=True,
+        knock_join_rule=True,
        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=True,
-        msc3667_int_only_power_levels=True,
-        msc3821_redaction_rules=False,
+        knock_restricted_join_rule=True,
+        enforce_int_power_levels=True,
        msc3931_push_features=(),
-        msc3989_redaction_rules=True,
-    )
-    MSC3820opt2 = RoomVersion(
-        # Based upon v10
-        "org.matrix.msc3820.opt2",
-        RoomDisposition.UNSTABLE,
-        EventFormatVersions.ROOM_V4_PLUS,
-        StateResolutionVersions.V2,
-        enforce_key_validity=True,
-        special_case_aliases_auth=False,
-        strict_canonicaljson=True,
-        limit_notifications_power_levels=True,
-        msc2175_implicit_room_creator=True,  # Used by MSC3820
-        msc2176_redaction_rules=True,  # Used by MSC3820
-        msc3083_join_rules=True,
-        msc3375_redaction_rules=True,
-        msc2403_knocking=True,
-        msc2716_historical=False,
-        msc2716_redactions=False,
-        msc3389_relation_redactions=False,
-        msc3787_knock_restricted_join_rule=True,
-        msc3667_int_only_power_levels=True,
-        msc3821_redaction_rules=True,  # Used by MSC3820
-        msc3931_push_features=(),
-        msc3989_redaction_rules=True,  # Used by MSC3820
    )


@@ -520,15 +344,11 @@ KNOWN_ROOM_VERSIONS: Dict[str, RoomVersion] = {
        RoomVersions.V4,
        RoomVersions.V5,
        RoomVersions.V6,
-        RoomVersions.MSC2176,
        RoomVersions.V7,
        RoomVersions.V8,
        RoomVersions.V9,
-        RoomVersions.MSC3787,
        RoomVersions.V10,
-        RoomVersions.MSC2716v4,
-        RoomVersions.MSC3989,
-        RoomVersions.MSC3820opt2,
+        RoomVersions.V11,
    )
 }

@@ -557,12 +377,12 @@ MSC3244_CAPABILITIES = {
        RoomVersionCapability(
            "knock",
            RoomVersions.V7,
-            lambda room_version: room_version.msc2403_knocking,
+            lambda room_version: room_version.knock_join_rule,
        ),
        RoomVersionCapability(
            "restricted",
            RoomVersions.V9,
-            lambda room_version: room_version.msc3083_join_rules,
+            lambda room_version: room_version.restricted_join_rule,
        ),
    )
 }
@@ -386,6 +386,7 @@ def listen_unix(


 def listen_http(
+    hs: "HomeServer",
    listener_config: ListenerConfig,
    root_resource: Resource,
    version_string: str,
@@ -406,6 +407,7 @@ def listen_http(
        version_string,
        max_request_body_size=max_request_body_size,
        reactor=reactor,
+        hs=hs,
    )

    if isinstance(listener_config, TCPListenerConfig):
@@ -83,7 +83,6 @@ from synapse.storage.databases.main.receipts import ReceiptsWorkerStore
 from synapse.storage.databases.main.registration import RegistrationWorkerStore
 from synapse.storage.databases.main.relations import RelationsWorkerStore
 from synapse.storage.databases.main.room import RoomWorkerStore
-from synapse.storage.databases.main.room_batch import RoomBatchStore
 from synapse.storage.databases.main.roommember import RoomMemberWorkerStore
 from synapse.storage.databases.main.search import SearchStore
 from synapse.storage.databases.main.session import SessionStore
@@ -120,7 +119,6 @@ class GenericWorkerStore(
    # the races it creates aren't too bad.
    KeyStore,
    RoomWorkerStore,
-    RoomBatchStore,
    DirectoryWorkerStore,
    PushRulesWorkerStore,
    ApplicationServiceTransactionWorkerStore,
@@ -223,6 +221,7 @@ class GenericWorkerServer(HomeServer):
        root_resource = create_resource_tree(resources, OptionsResource())

        _base.listen_http(
+            self,
            listener_config,
            root_resource,
            self.version_string,
@@ -139,6 +139,7 @@ class SynapseHomeServer(HomeServer):
            root_resource = OptionsResource()

        ports = listen_http(
+            self,
            listener_config,
            create_resource_tree(resources, root_resource),
            self.version_string,
@@ -16,9 +16,6 @@ import logging
 import urllib.parse
 from typing import (
    TYPE_CHECKING,
-    Any,
-    Awaitable,
-    Callable,
    Dict,
    Iterable,
    List,
@@ -27,10 +24,11 @@ from typing import (
    Sequence,
    Tuple,
    TypeVar,
+    Union,
 )

 from prometheus_client import Counter
-from typing_extensions import Concatenate, ParamSpec, TypeGuard
+from typing_extensions import ParamSpec, TypeGuard

 from synapse.api.constants import EventTypes, Membership, ThirdPartyEntityKind
 from synapse.api.errors import CodeMessageException, HttpResponseException
@@ -80,9 +78,7 @@ sent_todevice_counter = Counter(

 HOUR_IN_MS = 60 * 60 * 1000

-
 APP_SERVICE_PREFIX = "/_matrix/app/v1"
-APP_SERVICE_UNSTABLE_PREFIX = "/_matrix/app/unstable"

 P = ParamSpec("P")
 R = TypeVar("R")
@@ -123,52 +119,12 @@ class ApplicationServiceApi(SimpleHttpClient):
    def __init__(self, hs: "HomeServer"):
        super().__init__(hs)
        self.clock = hs.get_clock()
+        self.config = hs.config.appservice

        self.protocol_meta_cache: ResponseCache[Tuple[str, str]] = ResponseCache(
            hs.get_clock(), "as_protocol_meta", timeout_ms=HOUR_IN_MS
        )

-    async def _send_with_fallbacks(
-        self,
-        service: "ApplicationService",
-        prefixes: List[str],
-        path: str,
-        func: Callable[Concatenate[str, P], Awaitable[R]],
-        *args: P.args,
-        **kwargs: P.kwargs,
-    ) -> R:
-        """
-        Attempt to call an application service with multiple paths, falling back
-        until one succeeds.
-
-        Args:
-            service: The appliacation service, this provides the base URL.
-            prefixes: A last of paths to try in order for the requests.
-            path: A suffix to append to each prefix.
-            func: The function to call, the first argument will be the full
-                endpoint to fetch. Other arguments are provided by args/kwargs.
-
-        Returns:
-            The return value of func.
-        """
-        for i, prefix in enumerate(prefixes, start=1):
-            uri = f"{service.url}{prefix}{path}"
-            try:
-                return await func(uri, *args, **kwargs)
-            except HttpResponseException as e:
-                # If an error is received that is due to an unrecognised path,
-                # fallback to next path (if one exists). Otherwise, consider it
-                # a legitimate error and raise.
-                if i < len(prefixes) and is_unknown_endpoint(e):
-                    continue
-                raise
-            except Exception:
-                # Unexpected exceptions get sent to the caller.
-                raise
-
-        # The function should always exit via the return or raise above this.
-        raise RuntimeError("Unexpected fallback behaviour. This should never be seen.")
-
    async def query_user(self, service: "ApplicationService", user_id: str) -> bool:
        if service.url is None:
            return False
@@ -177,12 +133,12 @@ class ApplicationServiceApi(SimpleHttpClient):
        assert service.hs_token is not None

        try:
-            response = await self._send_with_fallbacks(
-                service,
-                [APP_SERVICE_PREFIX, ""],
-                f"/users/{urllib.parse.quote(user_id)}",
-                self.get_json,
-                {"access_token": service.hs_token},
+            args = None
+            if self.config.use_appservice_legacy_authorization:
+                args = {"access_token": service.hs_token}
+            response = await self.get_json(
+                f"{service.url}{APP_SERVICE_PREFIX}/users/{urllib.parse.quote(user_id)}",
+                args,
                headers={"Authorization": [f"Bearer {service.hs_token}"]},
            )
            if response is not None:  # just an empty json object
@@ -203,12 +159,12 @@ class ApplicationServiceApi(SimpleHttpClient):
        assert service.hs_token is not None

        try:
-            response = await self._send_with_fallbacks(
-                service,
-                [APP_SERVICE_PREFIX, ""],
-                f"/rooms/{urllib.parse.quote(alias)}",
-                self.get_json,
-                {"access_token": service.hs_token},
+            args = None
+            if self.config.use_appservice_legacy_authorization:
+                args = {"access_token": service.hs_token}
+            response = await self.get_json(
+                f"{service.url}{APP_SERVICE_PREFIX}/rooms/{urllib.parse.quote(alias)}",
+                args,
                headers={"Authorization": [f"Bearer {service.hs_token}"]},
            )
            if response is not None:  # just an empty json object
@@ -241,15 +197,14 @@ class ApplicationServiceApi(SimpleHttpClient):
        assert service.hs_token is not None

        try:
-            args: Mapping[Any, Any] = {
-                **fields,
-                b"access_token": service.hs_token,
-            }
-            response = await self._send_with_fallbacks(
-                service,
-                [APP_SERVICE_PREFIX, APP_SERVICE_UNSTABLE_PREFIX],
-                f"/thirdparty/{kind}/{urllib.parse.quote(protocol)}",
-                self.get_json,
+            args: Mapping[bytes, Union[List[bytes], str]] = fields
+            if self.config.use_appservice_legacy_authorization:
+                args = {
+                    **fields,
+                    b"access_token": service.hs_token,
+                }
+            response = await self.get_json(
+                f"{service.url}{APP_SERVICE_PREFIX}/thirdparty/{kind}/{urllib.parse.quote(protocol)}",
                args=args,
                headers={"Authorization": [f"Bearer {service.hs_token}"]},
            )
@@ -285,12 +240,12 @@ class ApplicationServiceApi(SimpleHttpClient):
            # This is required by the configuration.
            assert service.hs_token is not None
            try:
-                info = await self._send_with_fallbacks(
-                    service,
-                    [APP_SERVICE_PREFIX, APP_SERVICE_UNSTABLE_PREFIX],
-                    f"/thirdparty/protocol/{urllib.parse.quote(protocol)}",
-                    self.get_json,
-                    {"access_token": service.hs_token},
+                args = None
+                if self.config.use_appservice_legacy_authorization:
+                    args = {"access_token": service.hs_token}
+                info = await self.get_json(
+                    f"{service.url}{APP_SERVICE_PREFIX}/thirdparty/protocol/{urllib.parse.quote(protocol)}",
+                    args,
                    headers={"Authorization": [f"Bearer {service.hs_token}"]},
                )

@@ -401,13 +356,14 @@ class ApplicationServiceApi(SimpleHttpClient):
                }

        try:
-            await self._send_with_fallbacks(
-                service,
-                [APP_SERVICE_PREFIX, ""],
-                f"/transactions/{urllib.parse.quote(str(txn_id))}",
-                self.put_json,
+            args = None
+            if self.config.use_appservice_legacy_authorization:
+                args = {"access_token": service.hs_token}
+
+            await self.put_json(
+                f"{service.url}{APP_SERVICE_PREFIX}/transactions/{urllib.parse.quote(str(txn_id))}",
                json_body=body,
-                args={"access_token": service.hs_token},
+                args=args,
                headers={"Authorization": [f"Bearer {service.hs_token}"]},
            )
            if logger.isEnabledFor(logging.DEBUG):
@@ -43,6 +43,14 @@ class AppServiceConfig(Config):
            )

        self.track_appservice_user_ips = config.get("track_appservice_user_ips", False)
+        self.use_appservice_legacy_authorization = config.get(
+            "use_appservice_legacy_authorization", False
+        )
+        if self.use_appservice_legacy_authorization:
+            logger.warning(
+                "The use of appservice legacy authorization via query params is deprecated"
+                " and should be considered insecure."
+            )


 def load_appservices(
@@ -29,7 +29,14 @@ class AuthConfig(Config):
        if password_config is None:
            password_config = {}

-        passwords_enabled = password_config.get("enabled", True)
+        # The default value of password_config.enabled is True, unless msc3861 is enabled.
+        msc3861_enabled = (
+            (config.get("experimental_features") or {})
+            .get("msc3861", {})
+            .get("enabled", False)
+        )
+        passwords_enabled = password_config.get("enabled", not msc3861_enabled)
+
        # 'only_for_reauth' allows users who have previously set a password to use it,
        # even though passwords would otherwise be disabled.
        passwords_for_reauth_only = passwords_enabled == "only_for_reauth"
@@ -53,3 +60,13 @@ class AuthConfig(Config):
        self.ui_auth_session_timeout = self.parse_duration(
            ui_auth.get("session_timeout", 0)
        )
+
+        # Logging in with an existing session.
+        login_via_existing = config.get("login_via_existing_session", {})
+        self.login_via_existing_enabled = login_via_existing.get("enabled", False)
+        self.login_via_existing_require_ui_auth = login_via_existing.get(
+            "require_ui_auth", True
+        )
+        self.login_via_existing_token_timeout = self.parse_duration(
+            login_via_existing.get("token_timeout", "5m")
+        )
@@ -47,6 +47,10 @@ class CasConfig(Config):
                required_attributes
            )

+            self.idp_name = cas_config.get("idp_name", "CAS")
+            self.idp_icon = cas_config.get("idp_icon")
+            self.idp_brand = cas_config.get("idp_brand")
+
        else:
            self.cas_server_url = None
            self.cas_service_url = None
@@ -12,15 +12,210 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.

-from typing import Any, Optional
+import enum
+from typing import TYPE_CHECKING, Any, Optional

 import attr
+import attr.validators

 from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersions
 from synapse.config import ConfigError
-from synapse.config._base import Config
+from synapse.config._base import Config, RootConfig
 from synapse.types import JsonDict

+# Determine whether authlib is installed.
+try:
+    import authlib  # noqa: F401
+
+    HAS_AUTHLIB = True
+except ImportError:
+    HAS_AUTHLIB = False
+
+if TYPE_CHECKING:
+    # Only import this if we're type checking, as it might not be installed at runtime.
+    from authlib.jose.rfc7517 import JsonWebKey
+
+
+class ClientAuthMethod(enum.Enum):
+    """List of supported client auth methods."""
+
+    CLIENT_SECRET_POST = "client_secret_post"
+    CLIENT_SECRET_BASIC = "client_secret_basic"
+    CLIENT_SECRET_JWT = "client_secret_jwt"
+    PRIVATE_KEY_JWT = "private_key_jwt"
+
+
+def _parse_jwks(jwks: Optional[JsonDict]) -> Optional["JsonWebKey"]:
+    """A helper function to parse a JWK dict into a JsonWebKey."""
+
+    if jwks is None:
+        return None
+
+    from authlib.jose.rfc7517 import JsonWebKey
+
+    return JsonWebKey.import_key(jwks)
+
+
+@attr.s(slots=True, frozen=True)
+class MSC3861:
+    """Configuration for MSC3861: Matrix architecture change to delegate authentication via OIDC"""
+
+    enabled: bool = attr.ib(default=False, validator=attr.validators.instance_of(bool))
+    """Whether to enable MSC3861 auth delegation."""
+
+    @enabled.validator
+    def _check_enabled(self, attribute: attr.Attribute, value: bool) -> None:
+        # Only allow enabling MSC3861 if authlib is installed
+        if value and not HAS_AUTHLIB:
+            raise ConfigError(
+                "MSC3861 is enabled but authlib is not installed. "
+                "Please install authlib to use MSC3861.",
+                ("experimental", "msc3861", "enabled"),
+            )
+
+    issuer: str = attr.ib(default="", validator=attr.validators.instance_of(str))
+    """The URL of the OIDC Provider."""
+
+    issuer_metadata: Optional[JsonDict] = attr.ib(default=None)
+    """The issuer metadata to use, otherwise discovered from /.well-known/openid-configuration as per MSC2965."""
+
+    client_id: str = attr.ib(
+        default="",
+        validator=attr.validators.instance_of(str),
+    )
+    """The client ID to use when calling the introspection endpoint."""
+
+    client_auth_method: ClientAuthMethod = attr.ib(
+        default=ClientAuthMethod.CLIENT_SECRET_POST, converter=ClientAuthMethod
+    )
+    """The auth method used when calling the introspection endpoint."""
+
+    client_secret: Optional[str] = attr.ib(
+        default=None,
+        validator=attr.validators.optional(attr.validators.instance_of(str)),
+    )
+    """
+    The client secret to use when calling the introspection endpoint,
+    when using any of the client_secret_* client auth methods.
+    """
+
+    jwk: Optional["JsonWebKey"] = attr.ib(default=None, converter=_parse_jwks)
+    """
+    The JWKS to use when calling the introspection endpoint,
+    when using the private_key_jwt client auth method.
+    """
+
+    @client_auth_method.validator
+    def _check_client_auth_method(
+        self, attribute: attr.Attribute, value: ClientAuthMethod
+    ) -> None:
+        # Check that the right client credentials are provided for the client auth method.
+        if not self.enabled:
+            return
+
+        if value == ClientAuthMethod.PRIVATE_KEY_JWT and self.jwk is None:
+            raise ConfigError(
+                "A JWKS must be provided when using the private_key_jwt client auth method",
+                ("experimental", "msc3861", "client_auth_method"),
+            )
+
+        if (
+            value
+            in (
+                ClientAuthMethod.CLIENT_SECRET_POST,
+                ClientAuthMethod.CLIENT_SECRET_BASIC,
+                ClientAuthMethod.CLIENT_SECRET_JWT,
+            )
+            and self.client_secret is None
+        ):
+            raise ConfigError(
+                f"A client secret must be provided when using the {value} client auth method",
+                ("experimental", "msc3861", "client_auth_method"),
+            )
+
+    account_management_url: Optional[str] = attr.ib(
+        default=None,
+        validator=attr.validators.optional(attr.validators.instance_of(str)),
+    )
+    """The URL of the My Account page on the OIDC Provider as per MSC2965."""
+
+    admin_token: Optional[str] = attr.ib(
+        default=None,
+        validator=attr.validators.optional(attr.validators.instance_of(str)),
+    )
+    """
+    A token that should be considered as an admin token.
+    This is used by the OIDC provider, to make admin calls to Synapse.
+    """
+
+    def check_config_conflicts(self, root: RootConfig) -> None:
+        """Checks for any configuration conflicts with other parts of Synapse.
+
+        Raises:
+            ConfigError: If there are any configuration conflicts.
+        """
+
+        if not self.enabled:
+            return
+
+        if (
+            root.auth.password_enabled_for_reauth
+            or root.auth.password_enabled_for_login
+        ):
+            raise ConfigError(
+                "Password auth cannot be enabled when OAuth delegation is enabled",
+                ("password_config", "enabled"),
+            )
+
+        if root.registration.enable_registration:
+            raise ConfigError(
+                "Registration cannot be enabled when OAuth delegation is enabled",
+                ("enable_registration",),
+            )
+
+        if (
+            root.oidc.oidc_enabled
+            or root.saml2.saml2_enabled
+            or root.cas.cas_enabled
+            or root.jwt.jwt_enabled
+        ):
+            raise ConfigError("SSO cannot be enabled when OAuth delegation is enabled")
+
+        if bool(root.authproviders.password_providers):
+            raise ConfigError(
+                "Password auth providers cannot be enabled when OAuth delegation is enabled"
+            )
+
+        if root.captcha.enable_registration_captcha:
+            raise ConfigError(
+                "CAPTCHA cannot be enabled when OAuth delegation is enabled",
+                ("captcha", "enable_registration_captcha"),
+            )
+
+        if root.auth.login_via_existing_enabled:
+            raise ConfigError(
+                "Login via existing session cannot be enabled when OAuth delegation is enabled",
+                ("login_via_existing_session", "enabled"),
+            )
+
+        if root.registration.refresh_token_lifetime:
+            raise ConfigError(
+                "refresh_token_lifetime cannot be set when OAuth delegation is enabled",
+                ("refresh_token_lifetime",),
+            )
+
+        if root.registration.nonrefreshable_access_token_lifetime:
+            raise ConfigError(
+                "nonrefreshable_access_token_lifetime cannot be set when OAuth delegation is enabled",
+                ("nonrefreshable_access_token_lifetime",),
+            )
+
+        if root.registration.session_lifetime:
+            raise ConfigError(
+                "session_lifetime cannot be set when OAuth delegation is enabled",
+                ("session_lifetime",),
+            )
+

@attr.s(auto_attribs=True, frozen=True, slots=True)
 class MSC3866Config:
@@ -46,8 +241,26 @@ class ExperimentalConfig(Config):
        # MSC3026 (busy presence state)
        self.msc3026_enabled: bool = experimental.get("msc3026_enabled", False)

-        # MSC2716 (importing historical messages)
-        self.msc2716_enabled: bool = experimental.get("msc2716_enabled", False)
+        # MSC2697 (device dehydration)
+        # Enabled by default since this option was added after adding the feature.
+        # It is not recommended that both MSC2697 and MSC3814 both be enabled at
+        # once.
+        self.msc2697_enabled: bool = experimental.get("msc2697_enabled", True)
+
+        # MSC3814 (dehydrated devices with SSSS)
+        # This is an alternative method to achieve the same goals as MSC2697.
+        # It is not recommended that both MSC2697 and MSC3814 both be enabled at
+        # once.
+        self.msc3814_enabled: bool = experimental.get("msc3814_enabled", False)
+
+        if self.msc2697_enabled and self.msc3814_enabled:
+            raise ConfigError(
+                "MSC2697 and MSC3814 should not both be enabled.",
+                (
+                    "experimental_features",
+                    "msc3814_enabled",
+                ),
+            )

        # MSC3244 (room version capabilities)
        self.msc3244_enabled: bool = experimental.get("msc3244_enabled", True)
@@ -118,13 +331,6 @@ class ExperimentalConfig(Config):
        # MSC3881: Remotely toggle push notifications for another client
        self.msc3881_enabled: bool = experimental.get("msc3881_enabled", False)

-        # MSC3882: Allow an existing session to sign in a new session
-        self.msc3882_enabled: bool = experimental.get("msc3882_enabled", False)
-        self.msc3882_ui_auth: bool = experimental.get("msc3882_ui_auth", True)
-        self.msc3882_token_timeout = self.parse_duration(
-            experimental.get("msc3882_token_timeout", "5m")
-        )
-
        # MSC3874: Filtering /messages with rel_types / not_rel_types.
        self.msc3874_enabled: bool = experimental.get("msc3874_enabled", False)

@@ -164,11 +370,6 @@ class ExperimentalConfig(Config):
        # MSC3391: Removing account data.
        self.msc3391_enabled = experimental.get("msc3391_enabled", False)

-        # MSC3952: Intentional mentions, this depends on MSC3966.
-        self.msc3952_intentional_mentions = experimental.get(
-            "msc3952_intentional_mentions", False
-        )
-
        # MSC3959: Do not generate notifications for edits.
        self.msc3958_supress_edit_notifs = experimental.get(
            "msc3958_supress_edit_notifs", False
@@ -182,11 +383,16 @@ class ExperimentalConfig(Config):
            "msc3981_recurse_relations", False
        )

-        # MSC3970: Scope transaction IDs to devices
-        self.msc3970_enabled = experimental.get("msc3970_enabled", False)
+        # MSC3861: Matrix architecture change to delegate authentication via OIDC
+        try:
+            self.msc3861 = MSC3861(**experimental.get("msc3861", {}))
+        except ValueError as exc:
+            raise ConfigError(
+                "Invalid MSC3861 configuration", ("experimental", "msc3861")
+            ) from exc

-        # MSC4009: E.164 Matrix IDs
-        self.msc4009_e164_mxids = experimental.get("msc4009_e164_mxids", False)
+        # Check that none of the other config options conflict with MSC3861 when enabled
+        self.msc3861.check_config_conflicts(self.root)

        # MSC4010: Do not allow setting m.push_rules account data.
        self.msc4010_push_rules_account_data = experimental.get(
@@ -22,6 +22,8 @@ class FederationConfig(Config):
    section = "federation"

    def read_config(self, config: JsonDict, **kwargs: Any) -> None:
+        federation_config = config.setdefault("federation", {})
+
        # FIXME: federation_domain_whitelist needs sytests
        self.federation_domain_whitelist: Optional[dict] = None
        federation_domain_whitelist = config.get("federation_domain_whitelist", None)
@@ -49,5 +51,37 @@ class FederationConfig(Config):
            "allow_device_name_lookup_over_federation", False
        )

+        # Allow for the configuration of timeout, max request retries
+        # and min/max retry delays in the matrix federation client.
+        self.client_timeout_ms = Config.parse_duration(
+            federation_config.get("client_timeout", "60s")
+        )
+        self.max_long_retry_delay_ms = Config.parse_duration(
+            federation_config.get("max_long_retry_delay", "60s")
+        )
+        self.max_short_retry_delay_ms = Config.parse_duration(
+            federation_config.get("max_short_retry_delay", "2s")
+        )
+        self.max_long_retries = federation_config.get("max_long_retries", 10)
+        self.max_short_retries = federation_config.get("max_short_retries", 3)
+
+        # Allow for the configuration of the backoff algorithm used
+        # when trying to reach an unavailable destination.
+        # Unlike previous configuration those values applies across
+        # multiple requests and the state of the backoff is stored on DB.
+        self.destination_min_retry_interval_ms = Config.parse_duration(
+            federation_config.get("destination_min_retry_interval", "10m")
+        )
+        self.destination_retry_multiplier = federation_config.get(
+            "destination_retry_multiplier", 2
+        )
+        self.destination_max_retry_interval_ms = min(
+            Config.parse_duration(
+                federation_config.get("destination_max_retry_interval", "7d")
+            ),
+            # Set a hard-limit to not overflow the database column.
+            2**62,
+        )
+

 _METRICS_FOR_DOMAINS_SCHEMA = {"type": "array", "items": {"type": "string"}}
@@ -89,8 +89,14 @@ class SAML2Config(Config):
            "grandfathered_mxid_source_attribute", "uid"
        )

+        # refers to a SAML IdP entity ID
        self.saml2_idp_entityid = saml2_config.get("idp_entityid", None)

+        # IdP properties for Matrix clients
+        self.idp_name = saml2_config.get("idp_name", "SAML")
+        self.idp_icon = saml2_config.get("idp_icon")
+        self.idp_brand = saml2_config.get("idp_brand")
+
        # user_mapping_provider may be None if the key is present but has no value
        ump_dict = saml2_config.get("user_mapping_provider") or {}

@@ -35,3 +35,4 @@ class UserDirectoryConfig(Config):
        self.user_directory_search_prefer_local_users = user_directory_config.get(
            "prefer_local_users", False
        )
+        self.show_locked_users = user_directory_config.get("show_locked_users", False)
--- a/Show More
+++ b/Show More
				`@@ -0,0 +1 @@`
				`Implements an admin API to lock an user without deactivating them. Based on [MSC3939](https://github.com/matrix-org/matrix-spec-proposals/pull/3939).`
				`@@ -0,0 +1 @@`
				`Fix long-standing bug where concurrent requests to change a user's push rules could cause a deadlock. Contributed by Nick @ Beeper (@fizzadar).`
				`@@ -0,0 +1 @@`
				Fix the type annotation on `run_db_interaction` in the Module API.
				`@@ -0,0 +1 @@`
				`Structured logging docs: add a link to explain the ELK stack`
				`@@ -0,0 +1 @@`
				`Allow customising the IdP display name, icon, and brand for SAML and CAS providers (in addition to OIDC provider).`
				`@@ -0,0 +1 @@`
				`Rename pagination and purge locks and add comments to explain why they exist and how they work.`
				`@@ -0,0 +1 @@`
				`Cache token introspection response from OIDC provider.`