channeld: fail channel on zero next_commitment_number - #9435
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BOLT ElementsProject#2 says if next_commitment_number is zero we MUST immediately fail the channel and broadcast the latest commitment. On an advanced channel a reset peer sends 0 for both numbers; we warn about the stale revocation_number and never reach the zero check, so the channel stays up. The test funds, pays so next_index is past 1, then injects that reestablish. It fails until the next commit. Reproduces: ElementsProject#9425 Reported-by: Leo Nash (@tankyleo) Signed-off-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
The existing BOLT ElementsProject#2 quote already required this, but the first bullet was unimplemented: the only zero check sat under next_commitment_number == next_index[REMOTE] - 1, after the stale-revocation warning. Implement that bullet next to the quote, and drop the nested copy. Fixes: ElementsProject#9425 Changelog-Fixed: Protocol: immediately fail the channel if channel_reestablish next_commitment_number is zero. Reported-by: Leo Nash (@tankyleo) Signed-off-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
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BOLT #2 says if
next_commitment_numberis zero we MUST immediately fail the channel and broadcast the latest commitment. On an advanced channel a reset peer sends 0 for both numbers; we warned about the stalenext_revocation_numberand never reached the zero check, so the channel stayed up.The existing BOLT quote already required this. The first bullet was unimplemented: the only zero check sat under
next_commitment_number == next_index[REMOTE] - 1, after the revocation warning. Implement that bullet next to the quote, and drop the nested copy.Two commits, test then fix:
tests: reproduce zero next_commitment_number on advanced channelchanneld: fail channel on zero next_commitment_numberLocal:
test_reestablish_zero_commitment_numberfails on the first commit (transient warning, no close) and passes on the second.Thanks to Leo Nash (@tankyleo) for the report.
Fixes: #9425
Reported-by: Leo Nash (@tankyleo)
Changelog-Fixed: Protocol: immediately fail the channel if channel_reestablish next_commitment_number is zero.