Provide remote channel public keys to signer

[rust-lightning] / lightning / src / util / enforcing_trait_impls.rs

diff --git a/lightning/src/util/enforcing_trait_impls.rs b/lightning/src/util/enforcing_trait_impls.rs
index ee90fe7acf8ead65b3b7701f619d398db154f4fd..e5b5a3179665f874dfdbaaf628c9051a2dc1635e 100644 (file)
--- a/lightning/src/util/enforcing_trait_impls.rs
+++ b/lightning/src/util/enforcing_trait_impls.rs
@@ -1,4 +1,4 @@
-use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys};
+use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys, ChannelPublicKeys};
 use ln::msgs;
 use chain::keysinterface::{ChannelKeys, InMemoryChannelKeys};
 
@@ -27,6 +27,27 @@ impl EnforcingChannelKeys {
                }
        }
 }
+
+impl EnforcingChannelKeys {
+       fn check_keys<T: secp256k1::Signing + secp256k1::Verification>(&self, secp_ctx: &Secp256k1<T>,
+                                                                      keys: &TxCreationKeys) {
+               let revocation_base = PublicKey::from_secret_key(secp_ctx, &self.inner.revocation_base_key);
+               let payment_base = PublicKey::from_secret_key(secp_ctx, &self.inner.payment_base_key);
+               let htlc_base = PublicKey::from_secret_key(secp_ctx, &self.inner.htlc_base_key);
+
+               let remote_points = self.inner.remote_channel_pubkeys.as_ref().unwrap();
+
+               let keys_expected = TxCreationKeys::new(secp_ctx,
+                                                       &keys.per_commitment_point,
+                                                       &remote_points.delayed_payment_basepoint,
+                                                       &remote_points.htlc_basepoint,
+                                                       &revocation_base,
+                                                       &payment_base,
+                                                       &htlc_base).unwrap();
+               if keys != &keys_expected { panic!("derived different per-tx keys") }
+       }
+}
+
 impl ChannelKeys for EnforcingChannelKeys {
        fn funding_key(&self) -> &SecretKey { self.inner.funding_key() }
        fn revocation_base_key(&self) -> &SecretKey { self.inner.revocation_base_key() }
@@ -35,8 +56,9 @@ impl ChannelKeys for EnforcingChannelKeys {
        fn htlc_base_key(&self) -> &SecretKey { self.inner.htlc_base_key() }
        fn commitment_seed(&self) -> &[u8; 32] { self.inner.commitment_seed() }
 
-       fn sign_remote_commitment<T: secp256k1::Signing>(&self, channel_value_satoshis: u64, feerate_per_kw: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1<T>) -> Result<(Signature, Vec<Signature>), ()> {
-               if commitment_tx.input.len() != 1 { panic!(); }
+       fn sign_remote_commitment<T: secp256k1::Signing + secp256k1::Verification>(&self, channel_value_satoshis: u64, feerate_per_kw: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1<T>) -> Result<(Signature, Vec<Signature>), ()> {
+               if commitment_tx.input.len() != 1 { panic!("lightning commitment transactions have a single input"); }
+               self.check_keys(secp_ctx, keys);
                let obscured_commitment_transaction_number = (commitment_tx.lock_time & 0xffffff) as u64 | ((commitment_tx.input[0].sequence as u64 & 0xffffff) << 3*8);
 
                {
@@ -60,11 +82,12 @@ impl ChannelKeys for EnforcingChannelKeys {
                self.inner.sign_channel_announcement(msg, secp_ctx)
        }
 
-       fn set_remote_funding_pubkey(&mut self, key: &PublicKey) {
-               self.inner.set_remote_funding_pubkey(key)
+       fn set_remote_channel_pubkeys(&mut self, channel_pubkeys: &ChannelPublicKeys) {
+               self.inner.set_remote_channel_pubkeys(channel_pubkeys)
        }
 }
 
+
 impl_writeable!(EnforcingChannelKeys, 0, {
        inner,
        commitment_number_obscure_and_last