fix(endpoint): route RTX/FEC repair packets to primary stream receiver#75
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nightness wants to merge 1 commit intowebrtc-rs:masterfrom
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fix(endpoint): route RTX/FEC repair packets to primary stream receiver#75nightness wants to merge 1 commit intowebrtc-rs:masterfrom
nightness wants to merge 1 commit intowebrtc-rs:masterfrom
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Three bugs caused all RTX/FEC repair packets to be silently dropped: 1. find_track_id_by_ssrc: outer SSRC search only matched primary SSRCs (coding.ssrc). RTX/FEC SSRCs live in coding.rtx.ssrc / coding.fec.ssrc and were never found. Fix: extend the .any() predicate to also check rtx/fec SSRCs; when matched via repair SSRC, return the primary stream's track_id immediately without triggering OnOpen events. 2. find_track_id_by_rid (rrid branch): after correctly associating the repair SSRC with the base stream's RTX parameters, the function fell through to None instead of returning Some(track_id). RTX packets with the rrid header extension were always dropped on every packet. 3. handle_undeclared_ssrc: codec lookup could match the RTX codec entry (which IS in codec_preferences) and incorrectly set up a repair stream as a primary track. Fix: explicitly exclude RTX codecs so only primary codecs are accepted here. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
Three bugs caused all RTX/FEC repair packets to be silently dropped:
Bug 1 —
find_track_id_by_ssrc: outer SSRC search misses repair SSRCsRTX/FEC SSRCs live in
coding.rtx.ssrc/coding.fec.ssrc, notcoding.ssrc. The outer transceiver search only checkedcoding.ssrc, so any packet with an RTX or FEC SSRC fell through toNoneand was dropped. Fix: extend the.any()predicate to also checkrtx/fecSSRCs. When a match is found via repair SSRC, the packet is routed to the primary stream's receiver immediately without firingOnOpenevents.Bug 2 —
find_track_id_by_rid(rridbranch): always returnedNoneThe
rridheader extension identifies a repair packet for a base stream identified byrid. The code correctly updatedcoding.rtx.ssrc = ssrc, but then fell through toNoneinstead of returning the primary stream'strack_id. Every RTX packet carryingrridwas dropped. Fix: addreturn Some(receiver.track().track_id().clone())after the SSRC update.Bug 3 —
handle_undeclared_ssrc: RTX codec matched as primaryRTX codec entries are included in
get_codec_preferences()(added during SDP negotiation). If an RTX packet arrived first in the single-section non-rid path, the codec lookup would find the RTX codec and incorrectly set it up as the primary track's codec. Fix: exclude RTX mime-type codecs from the lookup so only primary codecs are accepted.Test plan
cargo test -p rtc— all 246 tests passOnOpenis not fired for RTX SSRC sub-streams🤖 Generated with Claude Code