Limit datachannel IDs based on SCTP stream Ids - #3405
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NOTE! This patch depends on a corresponding patch in sctp that adds the numInboundStreams, numOutboundStreams and OnStreamResetComplete functions on Association. When an SCTP association is setup, the number of streams in each direction is "negotiated" between the peers. The max number of streams also determines the maximum ID a stream can be identified as. This patch makes sure to not trying to use stream IDs outside the valid range. The patch also makes sure IDs can be reused after reset. Before this patch, you could never open datachannels more than 65535 / 2 times within a session, even you only have one in use at a time.
JoTurk
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April 10, 2026 07:12
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Long-lived SCTP associations retained every allocated DataChannel ID after channels closed, eventually exhausting the negotiated stream space. Use the GizClaw SCTP reset-completion contract, release IDs only after completed resets, and bound allocation to negotiated stream counts. The close path unregisters the callback before aborting outside the transport lock to avoid lock inversion. Refs: #1, GizClaw/gizclaw#776, pion#3405 Generated with [Codex](https://github.com/openai)
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Update the SCTP fork pin so DataChannel identifiers are released only after both stream reset directions complete.
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The SCTP accept loop kept only the DataChannels that existed when the transport started. ACKs for later local channels were therefore parsed as remote OPEN packets and could close the shared association under load. - Classify accepted streams against the live local DataChannel registry - Track whether each channel originated remotely to avoid stale ID matches - Cover a second local channel created after SCTP startup with a distinct ID - Pin the SCTP fork commit that preserves established sessions on duplicate INIT Generated with [Codex](https://github.com/openai)
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Expose a handshake-specific SCTP retransmission limit and pass it to the forked SCTP association without changing DATA/T3, reconfiguration, or shutdown timers. Pin the SCTP fork commit that provides the compatible option.\n\nRefs: GizClaw/gizclaw#700\nUpstream-base: 381746d534f410658e0751cd3768b17727950027\n\nGenerated with [Codex](https://github.com/openai)
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Detached DataChannels leave the transport registry before their inbound ACK arrives. Track each local SCTP stream generation directly so the accept loop cannot parse those ACKs as remote OPEN messages, including when stream IDs overlap across delayed resets. Refs: GizClaw/gizclaw#699, GizClaw/gizclaw#700, GizClaw/gizclaw#776 Generated with [Codex](https://github.com/openai)
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SCTP can recreate a Stream object while completing a reset. Track ordered local DataChannel generations by stream ID so inbound ACKs remain classified correctly and delayed resets release only the oldest generation. Refs: GizClaw/gizclaw#699, GizClaw/gizclaw#700, GizClaw/gizclaw#776 Generated with [Codex](https://github.com/openai)
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Explicit DataChannel IDs could bypass the negotiated SCTP stream bound, and failed opens left stale transport entries and ID reservations behind. - Reject explicit IDs outside the negotiated bidirectional stream range - Roll back transport membership and reservations when local opens fail - Pin the SCTP fork revision that safely handles reset retransmissions - Cover the invalid and valid boundary paths plus failure cleanup Generated with [Codex](https://github.com/openai)
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Avoid immediately reusing the lowest parity-correct SCTP stream after reset completion. Advance allocations through the negotiated stream space and wrap only after a full cycle, while preserving reservation checks and bounded ID reuse. Generated with Codex
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Allow controlled APIs to set inbound and outbound SCTP stream counts while retaining the existing default when either value is zero. Pass the limits through normal and SNAP association setup so bounded end-to-end DataChannel ID reuse tests can negotiate a small real stream space.\n\nRefs: GizClaw/gizclaw#776\nUpstream-base: 381746d
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NOTE! This patch depends on a corresponding patch in sctp (pion/sctp#463) that adds the numInboundStreams, numOutboundStreams and OnStreamResetComplete functions on Association.
When an SCTP association is setup, the number of streams in each direction is "negotiated" between the peers. The max number of streams also determines the maximum ID a stream can be identified as.
This patch makes sure to not trying to use stream IDs outside the valid range.
The patch also makes sure IDs can be reused after reset. Before this patch, you could never open datachannels more than 65535 / 2 times within a session, even you only have one in use at a time.