+ let mut state = self.state.lock().unwrap();
+ let actual_commitment_number = commitment_tx.commitment_number();
+ let last_commitment_number = state.last_counterparty_commitment;
+ // These commitment numbers are backwards counting. We expect either the same as the previously encountered,
+ // or the next one.
+ assert!(last_commitment_number == actual_commitment_number || last_commitment_number - 1 == actual_commitment_number, "{} doesn't come after {}", actual_commitment_number, last_commitment_number);
+ // Ensure that the counterparty doesn't get more than two broadcastable commitments -
+ // the last and the one we are trying to sign
+ assert!(actual_commitment_number >= state.last_counterparty_revoked_commitment - 2, "cannot sign a commitment if second to last wasn't revoked - signing {} revoked {}", actual_commitment_number, state.last_counterparty_revoked_commitment);
+ state.last_counterparty_commitment = cmp::min(last_commitment_number, actual_commitment_number)
+ }
+
+ Ok(self.inner.sign_counterparty_commitment(commitment_tx, preimages, secp_ctx).unwrap())
+ }
+
+ fn validate_counterparty_revocation(&self, idx: u64, _secret: &SecretKey) -> Result<(), ()> {
+ let mut state = self.state.lock().unwrap();
+ assert!(idx == state.last_counterparty_revoked_commitment || idx == state.last_counterparty_revoked_commitment - 1, "expecting to validate the current or next counterparty revocation - trying {}, current {}", idx, state.last_counterparty_revoked_commitment);
+ state.last_counterparty_revoked_commitment = idx;
+ Ok(())
+ }
+
+ fn sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()> {
+ let trusted_tx = self.verify_holder_commitment_tx(commitment_tx, secp_ctx);
+ let commitment_txid = trusted_tx.txid();
+ let holder_csv = self.inner.counterparty_selected_contest_delay();
+
+ let state = self.state.lock().unwrap();
+ let commitment_number = trusted_tx.commitment_number();
+ if state.last_holder_revoked_commitment - 1 != commitment_number && state.last_holder_revoked_commitment - 2 != commitment_number {
+ if !self.disable_revocation_policy_check {
+ panic!("can only sign the next two unrevoked commitment numbers, revoked={} vs requested={} for {}",
+ state.last_holder_revoked_commitment, commitment_number, self.inner.commitment_seed[0])