From be9be2553f0f18baed07755e81669fd374f3525a Mon Sep 17 00:00:00 2001 From: Neil Alexander Date: Fri, 13 May 2022 11:52:04 +0100 Subject: [PATCH] Resolve over old and new extremities (#2457) * Feed existing state into state res when calculating state from new extremities * Remove duplicates * Fix bug * Sort and unique * Update to matrix-org/gomatrixserverlib#308 * Trim the slice properly * Update gomatrixserverlib again * Update to matrix-org/gomatrixserverlib#308 --- go.mod | 2 +- go.sum | 4 ++-- .../internal/input/input_latest_events.go | 19 +++++++++++++------ roomserver/types/types.go | 15 +++++++++++++++ 4 files changed, 31 insertions(+), 9 deletions(-) diff --git a/go.mod b/go.mod index ca817b00f..ecdeb77fa 100644 --- a/go.mod +++ b/go.mod @@ -30,7 +30,7 @@ require ( github.com/matrix-org/dugong v0.0.0-20210921133753-66e6b1c67e2e github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91 github.com/matrix-org/gomatrix v0.0.0-20210324163249-be2af5ef2e16 - github.com/matrix-org/gomatrixserverlib v0.0.0-20220509120958-8d818048c34c + github.com/matrix-org/gomatrixserverlib v0.0.0-20220513103617-eee8fd528433 github.com/matrix-org/pinecone v0.0.0-20220408153826-2999ea29ed48 github.com/matrix-org/util v0.0.0-20200807132607-55161520e1d4 github.com/mattn/go-sqlite3 v1.14.10 diff --git a/go.sum b/go.sum index 7544768c3..145c2a04c 100644 --- a/go.sum +++ b/go.sum @@ -795,8 +795,8 @@ github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91/go.mod h1 github.com/matrix-org/gomatrix v0.0.0-20190528120928-7df988a63f26/go.mod h1:3fxX6gUjWyI/2Bt7J1OLhpCzOfO/bB3AiX0cJtEKud0= github.com/matrix-org/gomatrix v0.0.0-20210324163249-be2af5ef2e16 h1:ZtO5uywdd5dLDCud4r0r55eP4j9FuUNpl60Gmntcop4= github.com/matrix-org/gomatrix v0.0.0-20210324163249-be2af5ef2e16/go.mod h1:/gBX06Kw0exX1HrwmoBibFA98yBk/jxKpGVeyQbff+s= -github.com/matrix-org/gomatrixserverlib v0.0.0-20220509120958-8d818048c34c h1:KqzqFWxvs90pcDaW9QEveW+Q5JcEYuNnKyaqXc+ohno= -github.com/matrix-org/gomatrixserverlib v0.0.0-20220509120958-8d818048c34c/go.mod h1:V5eO8rn/C3rcxig37A/BCeKerLFS+9Avg/77FIeTZ48= +github.com/matrix-org/gomatrixserverlib v0.0.0-20220513103617-eee8fd528433 h1:nwAlThHGPI2EAAJklXvgMcdhXF6ZiHp60+fmaYMoaDA= +github.com/matrix-org/gomatrixserverlib v0.0.0-20220513103617-eee8fd528433/go.mod h1:V5eO8rn/C3rcxig37A/BCeKerLFS+9Avg/77FIeTZ48= github.com/matrix-org/pinecone v0.0.0-20220408153826-2999ea29ed48 h1:W0sjjC6yjskHX4mb0nk3p0fXAlbU5bAFUFeEtlrPASE= github.com/matrix-org/pinecone v0.0.0-20220408153826-2999ea29ed48/go.mod h1:ulJzsVOTssIVp1j/m5eI//4VpAGDkMt5NrRuAVX7wpc= github.com/matrix-org/util v0.0.0-20190711121626-527ce5ddefc7/go.mod h1:vVQlW/emklohkZnOPwD3LrZUBqdfsbiyO3p1lNV8F6U= diff --git a/roomserver/internal/input/input_latest_events.go b/roomserver/internal/input/input_latest_events.go index 9ad8b0422..e4c138d58 100644 --- a/roomserver/internal/input/input_latest_events.go +++ b/roomserver/internal/input/input_latest_events.go @@ -233,12 +233,19 @@ func (u *latestEventsUpdater) latestState() error { } } - // Get a list of the current latest events. This may or may not - // include the new event from the input path, depending on whether - // it is a forward extremity or not. - latestStateAtEvents := make([]types.StateAtEvent, len(u.latest)) - for i := range u.latest { - latestStateAtEvents[i] = u.latest[i].StateAtEvent + // Take the old set of extremities and the new set of extremities and + // mash them together into a list. This may or may not include the new event + // from the input path, depending on whether it became a forward extremity + // or not. We'll then run state resolution across all of them to determine + // the new current state of the room. Including the old extremities here + // ensures that new forward extremities with bad state snapshots (from + // possible malicious actors) can't completely corrupt the room state + // away from what it was before. + combinedExtremities := types.StateAtEventAndReferences(append(u.oldLatest, u.latest...)) + combinedExtremities = combinedExtremities[:util.SortAndUnique(combinedExtremities)] + latestStateAtEvents := make([]types.StateAtEvent, len(combinedExtremities)) + for i := range combinedExtremities { + latestStateAtEvents[i] = combinedExtremities[i].StateAtEvent } // Takes the NIDs of the latest events and creates a state snapshot diff --git a/roomserver/types/types.go b/roomserver/types/types.go index 65fbee04e..ce4e5fd1e 100644 --- a/roomserver/types/types.go +++ b/roomserver/types/types.go @@ -18,6 +18,7 @@ package types import ( "encoding/json" "sort" + "strings" "github.com/matrix-org/gomatrixserverlib" "golang.org/x/crypto/blake2b" @@ -166,6 +167,20 @@ type StateAtEventAndReference struct { gomatrixserverlib.EventReference } +type StateAtEventAndReferences []StateAtEventAndReference + +func (s StateAtEventAndReferences) Less(a, b int) bool { + return strings.Compare(s[a].EventID, s[b].EventID) < 0 +} + +func (s StateAtEventAndReferences) Len() int { + return len(s) +} + +func (s StateAtEventAndReferences) Swap(a, b int) { + s[a], s[b] = s[b], s[a] +} + // An Event is a gomatrixserverlib.Event with the numeric event ID attached. // It is when performing bulk event lookup in the database. type Event struct {