smite-ir: implement funding flow generator#141
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Prevent funding transactions from reusing the same inputs across multiple transaction constructions. Without this, independently built funding transactions can select overlapping UTXOs, causing later broadcasts to fail as non-fee-bumping RBF replacements or making signing fail once the shared inputs have already been spent. Signed-off-by: Nishant Bansal <nishant.bansal.282003@gmail.com>
The fuzzer may broadcast a transaction that is already confirmed. Its inputs are spent, so the wallet can no longer fully sign it. Check the confirmation count before signing and return early when the transaction is already on-chain. Signed-off-by: Nishant Bansal <nishant.bansal.282003@gmail.com>
Pass a maxfeerate of 0 to bitcoin-cli sendrawtransaction so broadcasts are accepted at any fee rate, bypassing the default high-feerate safety cap. Signed-off-by: Nishant Bansal <nishant.bansal.282003@gmail.com>
Reject funding transactions that would not be accepted under Bitcoin's default relay policy. Funding construction now fails for feerates below the minimum relay feerate and funding outputs below the dust threshold, avoiding transactions that cannot be relayed or mined by default. Signed-off-by: Nishant Bansal <nishant.bansal.282003@gmail.com>
Signed-off-by: Nishant Bansal <nishant.bansal.282003@gmail.com>
Signed-off-by: Nishant Bansal <nishant.bansal.282003@gmail.com>
morehouse
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morehouse
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Wow, I'm impressed at the coverage achieved already with disjoint generators for each message exchange. Do you still think it would we be worth creating a combined generator that threads all the correct variables through the whole flow?
We should also bump the CLN version, since I observed crashes that have been fixed in its latest release.
I have a PR to bump versions for CLN and LND. Once I've finished testing against LND I'll upload the PR.
patch the CLN polling interval from 30 seconds to 2 seconds (I arbitrarily chose the same value as LDK)
Yes, let's do this. If you've already verified that 2 seconds works, let's do that right now and tune it down after further experiments.
patch recv_non_ping to also reject gossip messages, since CLN was apparently sending channel_update before sending channel_ready
Yes I think in general we want to skip gossip when receiving messages, since peers are free to send gossip at any time. We can revisit the strategy here if/when we actually want to extract fields from the gossip.
| let second_per_commitment_point = builder.generate_fresh(VariableType::Point, rng); | ||
| let short_channel_id = builder.generate_fresh(VariableType::ShortChannelId, rng); |
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Why are second_per_commitment_point and short_channel_id generated fresh instead of doing pick_variable?
| // At least 1 DerivePoint instructions. | ||
| let derive_count = program | ||
| .instructions | ||
| .iter() | ||
| .filter(|i| matches!(i.operation, Operation::DerivePoint)) | ||
| .count(); | ||
| assert!( | ||
| derive_count >= 1, | ||
| "expected at least one DerivePoint, got {derive_count}" | ||
| ); |
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This check seems odd. I think it's true, there will always be at least one DerivePoint, but is it really a fundamental part of the structure that we want to verify?
2 participants
Adds
funding_createdandchannel_readygenerators.Depends-on: #137
Verified that all targets correctly send
funding_signedandchannel_readyonce the commitment transaction is signed and the funding transaction confirms. For CLN, we need to reduce the blockchain polling interval to receivechannel_readypromptly. We should also bump the CLN version, since I observed crashes that have been fixed in its latest release.All other targets were able to reach
channel_readywithout any issues, but for CLN I had to (mentioning this so we can discuss a solution and add a fix in smite):recv_non_pingto also reject gossip messages, since CLN was apparently sendingchannel_updatebefore sendingchannel_readycln-coverage.tar.gz
eclair-coverage.tar.gz
ldk-coverage.tar.gz
lnd-coverage.tar.gz