Merge pull request #451 from lightning-signer/txkeys

Provide remote channel public keys to signer

diff --git a/.gitignore b/.gitignore
index c795d9b53373103e2a75b2acfdcb1c27facb24e7..19ed4bd115a78efd45966f8fe9c144e421ca1b06 100644 (file)
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 /target/
+/hfuzz_target/
 /net-tokio/target/
 **/*.rs.bk
 Cargo.lock

diff --git a/fuzz/src/chanmon_consistency.rs b/fuzz/src/chanmon_consistency.rs
index d4a33427ef4b9a1b0eee8483d8f8d5b5e669bf2b..382886492dbd0a88ef245de713253ddad8fb9c6d 100644 (file)
--- a/fuzz/src/chanmon_consistency.rs
+++ b/fuzz/src/chanmon_consistency.rs
@@ -158,7 +158,7 @@ impl KeysInterface for KeyProvider {
                        delayed_payment_base_key:  SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, self.node_id]).unwrap(),
                        htlc_base_key:             SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, self.node_id]).unwrap(),
                        commitment_seed: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, self.node_id],
-                       remote_funding_pubkey: None,
+                       remote_channel_pubkeys: None,
                })
        }
 

diff --git a/fuzz/src/full_stack.rs b/fuzz/src/full_stack.rs
index e6496125ac656ded582209d631ae74db71ba728a..cd855f363fe1c6c4c6bda312a81dadf22a6ca5cf 100644 (file)
--- a/fuzz/src/full_stack.rs
+++ b/fuzz/src/full_stack.rs
@@ -257,7 +257,7 @@ impl KeysInterface for KeyProvider {
                                delayed_payment_base_key:  SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, ctr]).unwrap(),
                                htlc_base_key:             SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, ctr]).unwrap(),
                                commitment_seed: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, ctr],
-                               remote_funding_pubkey: None,
+                               remote_channel_pubkeys: None,
                        }
                } else {
                        InMemoryChannelKeys {
@@ -267,7 +267,7 @@ impl KeysInterface for KeyProvider {
                                delayed_payment_base_key:  SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, ctr]).unwrap(),
                                htlc_base_key:             SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, ctr]).unwrap(),
                                commitment_seed: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, ctr],
-                               remote_funding_pubkey: None,
+                               remote_channel_pubkeys: None,
                        }
                })
        }

diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs
index c001646263fdf0d7ae4e1f1c079ed02ab3b40135..689a16603743e228ffff64dfba9ea710474fdc43 100644 (file)
--- a/lightning/src/chain/keysinterface.rs
+++ b/lightning/src/chain/keysinterface.rs
@@ -24,7 +24,7 @@ use util::logger::Logger;
 use util::ser::Writeable;
 
 use ln::chan_utils;
-use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment, make_funding_redeemscript};
+use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys};
 use ln::msgs;
 
 use std::sync::Arc;
@@ -142,7 +142,7 @@ pub trait ChannelKeys : Send {
        /// TODO: Document the things someone using this interface should enforce before signing.
        /// TODO: Add more input vars to enable better checking (preferably removing commitment_tx and
        /// making the callee generate it via some util function we expose)!
-       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>), ()>;
+       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>), ()>;
 
        /// Create a signature for a (proposed) closing transaction.
        ///
@@ -158,11 +158,11 @@ pub trait ChannelKeys : Send {
        /// protocol.
        fn sign_channel_announcement<T: secp256k1::Signing>(&self, msg: &msgs::UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<T>) -> Result<Signature, ()>;
 
-       /// Set the remote funding key.  This is done immediately on incoming channels
+       /// Set the remote channel basepoints.  This is done immediately on incoming channels
        /// and as soon as the channel is accepted on outgoing channels.
        ///
        /// Will be called before any signatures are applied.
-       fn set_remote_funding_pubkey(&mut self, key: &PublicKey);
+       fn set_remote_channel_pubkeys(&mut self, channel_points: &ChannelPublicKeys);
 }
 
 #[derive(Clone)]
@@ -181,7 +181,7 @@ pub struct InMemoryChannelKeys {
        /// Commitment seed
        pub commitment_seed: [u8; 32],
        /// Remote funding pubkey
-       pub remote_funding_pubkey: Option<PublicKey>,
+       pub remote_channel_pubkeys: Option<ChannelPublicKeys>,
 }
 
 impl ChannelKeys for InMemoryChannelKeys {
@@ -192,12 +192,12 @@ impl ChannelKeys for InMemoryChannelKeys {
        fn htlc_base_key(&self) -> &SecretKey { &self.htlc_base_key }
        fn commitment_seed(&self) -> &[u8; 32] { &self.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>), ()> {
+       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 { return Err(()); }
 
                let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key);
-               let remote_funding_pubkey = self.remote_funding_pubkey.as_ref().expect("must set remote funding key before signing");
-               let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, remote_funding_pubkey);
+               let remote_channel_pubkeys = self.remote_channel_pubkeys.as_ref().expect("must set remote channel pubkeys before signing");
+               let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &remote_channel_pubkeys.funding_pubkey);
 
                let commitment_sighash = hash_to_message!(&bip143::SighashComponents::new(&commitment_tx).sighash_all(&commitment_tx.input[0], &channel_funding_redeemscript, channel_value_satoshis)[..]);
                let commitment_sig = secp_ctx.sign(&commitment_sighash, &self.funding_key);
@@ -236,9 +236,9 @@ impl ChannelKeys for InMemoryChannelKeys {
                Ok(secp_ctx.sign(&msghash, &self.funding_key))
        }
 
-       fn set_remote_funding_pubkey(&mut self, key: &PublicKey) {
-               assert!(self.remote_funding_pubkey.is_none(), "Already set remote funding key");
-               self.remote_funding_pubkey = Some(*key);
+       fn set_remote_channel_pubkeys(&mut self, channel_pubkeys: &ChannelPublicKeys) {
+               assert!(self.remote_channel_pubkeys.is_none(), "Already set remote channel pubkeys");
+               self.remote_channel_pubkeys = Some(channel_pubkeys.clone());
        }
 }
 
@@ -249,7 +249,7 @@ impl_writeable!(InMemoryChannelKeys, 0, {
        delayed_payment_base_key,
        htlc_base_key,
        commitment_seed,
-       remote_funding_pubkey
+       remote_channel_pubkeys
 });
 
 /// Simple KeysInterface implementor that takes a 32-byte seed for use as a BIP 32 extended key
@@ -398,7 +398,7 @@ impl KeysInterface for KeysManager {
                        delayed_payment_base_key,
                        htlc_base_key,
                        commitment_seed,
-                       remote_funding_pubkey: None,
+                       remote_channel_pubkeys: None,
                }
        }
 

diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs
index 263547204c415a963e2223c50da0a9841f2e61e1..51a2c4b042224464eacbfe5781c9ed36325b992e 100644 (file)
--- a/lightning/src/ln/chan_utils.rs
+++ b/lightning/src/ln/chan_utils.rs
@@ -18,7 +18,7 @@ use ln::channelmanager::{PaymentHash, PaymentPreimage};
 use ln::msgs::DecodeError;
 use util::ser::{Readable, Writeable, Writer, WriterWriteAdaptor};
 
-use secp256k1::key::{SecretKey,PublicKey};
+use secp256k1::key::{SecretKey, PublicKey};
 use secp256k1::{Secp256k1, Signature};
 use secp256k1;
 
@@ -137,24 +137,57 @@ pub(super) fn derive_public_revocation_key<T: secp256k1::Verification>(secp_ctx:
 
 /// The set of public keys which are used in the creation of one commitment transaction.
 /// These are derived from the channel base keys and per-commitment data.
+#[derive(PartialEq)]
 pub struct TxCreationKeys {
        /// The per-commitment public key which was used to derive the other keys.
        pub per_commitment_point: PublicKey,
        /// The revocation key which is used to allow the owner of the commitment transaction to
        /// provide their counterparty the ability to punish them if they broadcast an old state.
-       pub revocation_key: PublicKey,
+       pub(crate) revocation_key: PublicKey,
        /// A's HTLC Key
-       pub a_htlc_key: PublicKey,
+       pub(crate) a_htlc_key: PublicKey,
        /// B's HTLC Key
-       pub b_htlc_key: PublicKey,
+       pub(crate) b_htlc_key: PublicKey,
        /// A's Payment Key (which isn't allowed to be spent from for some delay)
-       pub a_delayed_payment_key: PublicKey,
+       pub(crate) a_delayed_payment_key: PublicKey,
        /// B's Payment Key
-       pub b_payment_key: PublicKey,
+       pub(crate) b_payment_key: PublicKey,
+}
+
+/// One counterparty's public keys which do not change over the life of a channel.
+#[derive(Clone)]
+pub struct ChannelPublicKeys {
+       /// The public key which is used to sign all commitment transactions, as it appears in the
+       /// on-chain channel lock-in 2-of-2 multisig output.
+       pub funding_pubkey: PublicKey,
+       /// The base point which is used (with derive_public_revocation_key) to derive per-commitment
+       /// revocation keys. The per-commitment revocation private key is then revealed by the owner of
+       /// a commitment transaction so that their counterparty can claim all available funds if they
+       /// broadcast an old state.
+       pub revocation_basepoint: PublicKey,
+       /// The base point which is used (with derive_public_key) to derive a per-commitment payment
+       /// public key which receives immediately-spendable non-HTLC-encumbered funds.
+       pub payment_basepoint: PublicKey,
+       /// The base point which is used (with derive_public_key) to derive a per-commitment payment
+       /// public key which receives non-HTLC-encumbered funds which are only available for spending
+       /// after some delay (or can be claimed via the revocation path).
+       pub delayed_payment_basepoint: PublicKey,
+       /// The base point which is used (with derive_public_key) to derive a per-commitment public key
+       /// which is used to encumber HTLC-in-flight outputs.
+       pub htlc_basepoint: PublicKey,
 }
 
+impl_writeable!(ChannelPublicKeys, 33*5, {
+       funding_pubkey,
+       revocation_basepoint,
+       payment_basepoint,
+       delayed_payment_basepoint,
+       htlc_basepoint
+});
+
+
 impl TxCreationKeys {
-       pub(super) fn new<T: secp256k1::Signing + secp256k1::Verification>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, a_delayed_payment_base: &PublicKey, a_htlc_base: &PublicKey, b_revocation_base: &PublicKey, b_payment_base: &PublicKey, b_htlc_base: &PublicKey) -> Result<TxCreationKeys, secp256k1::Error> {
+       pub(crate) fn new<T: secp256k1::Signing + secp256k1::Verification>(secp_ctx: &Secp256k1<T>, per_commitment_point: &PublicKey, a_delayed_payment_base: &PublicKey, a_htlc_base: &PublicKey, b_revocation_base: &PublicKey, b_payment_base: &PublicKey, b_htlc_base: &PublicKey) -> Result<TxCreationKeys, secp256k1::Error> {
                Ok(TxCreationKeys {
                        per_commitment_point: per_commitment_point.clone(),
                        revocation_key: derive_public_revocation_key(&secp_ctx, &per_commitment_point, &b_revocation_base)?,

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index d2a0cae9ba9120afb8e834931b3debb16ef3e647..02b1ae4ed2f58b413e8e4375716d490b6e0552e3 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -20,7 +20,7 @@ use ln::msgs;
 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
 use ln::channelmonitor::ChannelMonitor;
 use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingForwardHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash, BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
-use ln::chan_utils::{LocalCommitmentTransaction, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript};
+use ln::chan_utils::{LocalCommitmentTransaction, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys};
 use ln::chan_utils;
 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
 use chain::transaction::OutPoint;
@@ -335,11 +335,8 @@ pub(super) struct Channel<ChanSigner: ChannelKeys> {
        //implied by OUR_MAX_HTLCS: our_max_accepted_htlcs: u16,
        minimum_depth: u32,
 
-       their_funding_pubkey: Option<PublicKey>,
-       their_revocation_basepoint: Option<PublicKey>,
-       their_payment_basepoint: Option<PublicKey>,
-       their_delayed_payment_basepoint: Option<PublicKey>,
-       their_htlc_basepoint: Option<PublicKey>,
+       their_pubkeys: Option<ChannelPublicKeys>,
+
        their_cur_commitment_point: Option<PublicKey>,
 
        their_prev_commitment_point: Option<PublicKey>,
@@ -506,11 +503,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        their_max_accepted_htlcs: 0,
                        minimum_depth: 0, // Filled in in accept_channel
 
-                       their_funding_pubkey: None,
-                       their_revocation_basepoint: None,
-                       their_payment_basepoint: None,
-                       their_delayed_payment_basepoint: None,
-                       their_htlc_basepoint: None,
+                       their_pubkeys: None,
                        their_cur_commitment_point: None,
 
                        their_prev_commitment_point: None,
@@ -540,7 +533,14 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
        /// Assumes chain_hash has already been checked and corresponds with what we expect!
        pub fn new_from_req(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface<ChanKeySigner = ChanSigner>>, their_node_id: PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel<ChanSigner>, ChannelError> {
                let mut chan_keys = keys_provider.get_channel_keys(true);
-               chan_keys.set_remote_funding_pubkey(&msg.funding_pubkey);
+               let their_pubkeys = ChannelPublicKeys {
+                       funding_pubkey: msg.funding_pubkey,
+                       revocation_basepoint: msg.revocation_basepoint,
+                       payment_basepoint: msg.payment_basepoint,
+                       delayed_payment_basepoint: msg.delayed_payment_basepoint,
+                       htlc_basepoint: msg.htlc_basepoint
+               };
+               chan_keys.set_remote_channel_pubkeys(&their_pubkeys);
                let mut local_config = (*config).channel_options.clone();
 
                if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
@@ -722,11 +722,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        their_max_accepted_htlcs: msg.max_accepted_htlcs,
                        minimum_depth: config.own_channel_config.minimum_depth,
 
-                       their_funding_pubkey: Some(msg.funding_pubkey),
-                       their_revocation_basepoint: Some(msg.revocation_basepoint),
-                       their_payment_basepoint: Some(msg.payment_basepoint),
-                       their_delayed_payment_basepoint: Some(msg.delayed_payment_basepoint),
-                       their_htlc_basepoint: Some(msg.htlc_basepoint),
+                       their_pubkeys: Some(their_pubkeys),
                        their_cur_commitment_point: Some(msg.first_per_commitment_point),
 
                        their_prev_commitment_point: None,
@@ -761,11 +757,12 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let mut sha = Sha256::engine();
                let our_payment_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.payment_base_key());
 
+               let their_payment_basepoint = &self.their_pubkeys.as_ref().unwrap().payment_basepoint.serialize();
                if self.channel_outbound {
                        sha.input(&our_payment_basepoint.serialize());
-                       sha.input(&self.their_payment_basepoint.unwrap().serialize());
+                       sha.input(their_payment_basepoint);
                } else {
-                       sha.input(&self.their_payment_basepoint.unwrap().serialize());
+                       sha.input(their_payment_basepoint);
                        sha.input(&our_payment_basepoint.serialize());
                }
                let res = Sha256::from_engine(sha).into_inner();
@@ -1084,8 +1081,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(commitment_number));
                let delayed_payment_base = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.delayed_payment_base_key());
                let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key());
+               let their_pubkeys = self.their_pubkeys.as_ref().unwrap();
 
-               Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &self.their_revocation_basepoint.unwrap(), &self.their_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap()), "Local tx keys generation got bogus keys"))
+               Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &their_pubkeys.revocation_basepoint, &their_pubkeys.payment_basepoint, &their_pubkeys.htlc_basepoint), "Local tx keys generation got bogus keys"))
        }
 
        #[inline]
@@ -1098,8 +1096,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let payment_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.payment_base_key());
                let revocation_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.revocation_base_key());
                let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key());
+               let their_pubkeys = self.their_pubkeys.as_ref().unwrap();
 
-               Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &self.their_delayed_payment_basepoint.unwrap(), &self.their_htlc_basepoint.unwrap(), &revocation_basepoint, &payment_basepoint, &htlc_basepoint), "Remote tx keys generation got bogus keys"))
+               Ok(secp_check!(TxCreationKeys::new(&self.secp_ctx, &self.their_cur_commitment_point.unwrap(), &their_pubkeys.delayed_payment_basepoint, &their_pubkeys.htlc_basepoint, &revocation_basepoint, &payment_basepoint, &htlc_basepoint), "Remote tx keys generation got bogus keys"))
        }
 
        /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
@@ -1107,8 +1106,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
        /// Panics if called before accept_channel/new_from_req
        pub fn get_funding_redeemscript(&self) -> Script {
                let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key());
-               let their_funding_key = self.their_funding_pubkey.expect("get_funding_redeemscript only allowed after accept_channel");
-               make_funding_redeemscript(&our_funding_key, &their_funding_key)
+               make_funding_redeemscript(&our_funding_key, self.their_funding_pubkey())
        }
 
        /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output
@@ -1382,11 +1380,18 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                self.their_to_self_delay = msg.to_self_delay;
                self.their_max_accepted_htlcs = msg.max_accepted_htlcs;
                self.minimum_depth = msg.minimum_depth;
-               self.their_funding_pubkey = Some(msg.funding_pubkey);
-               self.their_revocation_basepoint = Some(msg.revocation_basepoint);
-               self.their_payment_basepoint = Some(msg.payment_basepoint);
-               self.their_delayed_payment_basepoint = Some(msg.delayed_payment_basepoint);
-               self.their_htlc_basepoint = Some(msg.htlc_basepoint);
+
+               let their_pubkeys = ChannelPublicKeys {
+                       funding_pubkey: msg.funding_pubkey,
+                       revocation_basepoint: msg.revocation_basepoint,
+                       payment_basepoint: msg.payment_basepoint,
+                       delayed_payment_basepoint: msg.delayed_payment_basepoint,
+                       htlc_basepoint: msg.htlc_basepoint
+               };
+
+               self.local_keys.set_remote_channel_pubkeys(&their_pubkeys);
+               self.their_pubkeys = Some(their_pubkeys);
+
                self.their_cur_commitment_point = Some(msg.first_per_commitment_point);
                self.their_shutdown_scriptpubkey = their_shutdown_scriptpubkey;
 
@@ -1395,7 +1400,6 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                self.channel_monitor.set_basic_channel_info(&msg.htlc_basepoint, &msg.delayed_payment_basepoint, msg.to_self_delay, funding_redeemscript, self.channel_value_satoshis, obscure_factor);
 
                self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
-               self.local_keys.set_remote_funding_pubkey(&msg.funding_pubkey);
 
                Ok(())
        }
@@ -1408,9 +1412,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]);
 
                // They sign the "local" commitment transaction...
-               secp_check!(self.secp_ctx.verify(&local_sighash, &sig, &self.their_funding_pubkey.unwrap()), "Invalid funding_created signature from peer");
+               secp_check!(self.secp_ctx.verify(&local_sighash, &sig, self.their_funding_pubkey()), "Invalid funding_created signature from peer");
 
-               let localtx = LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, sig, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey.as_ref().unwrap());
+               let localtx = LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, sig, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey());
 
                let remote_keys = self.build_remote_transaction_keys()?;
                let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw).0;
@@ -1421,6 +1425,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                Ok((remote_initial_commitment_tx, localtx, remote_signature, local_keys))
        }
 
+       fn their_funding_pubkey(&self) -> &PublicKey {
+               &self.their_pubkeys.as_ref().expect("their_funding_pubkey() only allowed after accept_channel").funding_pubkey
+       }
+
        pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor), ChannelError> {
                if self.channel_outbound {
                        return Err(ChannelError::Close("Received funding_created for an outbound channel?"));
@@ -1485,11 +1493,13 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0;
                let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]);
 
+               let their_funding_pubkey = &self.their_pubkeys.as_ref().unwrap().funding_pubkey;
+
                // They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish.
-               secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid funding_signed signature from peer");
+               secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, their_funding_pubkey), "Invalid funding_signed signature from peer");
 
                self.channel_monitor.provide_latest_local_commitment_tx_info(
-                       LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey.as_ref().unwrap()),
+                       LocalCommitmentTransaction::new_missing_local_sig(local_initial_commitment_tx, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), their_funding_pubkey),
                        local_keys, self.feerate_per_kw, Vec::new());
                self.channel_state = ChannelState::FundingSent as u32 | (self.channel_state & (ChannelState::MonitorUpdateFailed as u32));
                self.cur_local_commitment_transaction_number -= 1;
@@ -1737,8 +1747,8 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                };
                let local_commitment_txid = local_commitment_tx.0.txid();
                let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_commitment_tx.0).sighash_all(&local_commitment_tx.0.input[0], &funding_script, self.channel_value_satoshis)[..]);
-               log_trace!(self, "Checking commitment tx signature {} by key {} against tx {} with redeemscript {}", log_bytes!(msg.signature.serialize_compact()[..]), log_bytes!(self.their_funding_pubkey.unwrap().serialize()), encode::serialize_hex(&local_commitment_tx.0), encode::serialize_hex(&funding_script));
-               secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid commitment tx signature from peer");
+               log_trace!(self, "Checking commitment tx signature {} by key {} against tx {} with redeemscript {}", log_bytes!(msg.signature.serialize_compact()[..]), log_bytes!(self.their_funding_pubkey().serialize()), encode::serialize_hex(&local_commitment_tx.0), encode::serialize_hex(&funding_script));
+               secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey()), "Invalid commitment tx signature from peer");
 
                //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction
                if update_fee {
@@ -1786,9 +1796,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        }
                }
 
+               let their_funding_pubkey = self.their_pubkeys.as_ref().unwrap().funding_pubkey;
 
                self.channel_monitor.provide_latest_local_commitment_tx_info(
-                       LocalCommitmentTransaction::new_missing_local_sig(local_commitment_tx.0, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), self.their_funding_pubkey.as_ref().unwrap()),
+                       LocalCommitmentTransaction::new_missing_local_sig(local_commitment_tx.0, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), &their_funding_pubkey),
                        local_keys, self.feerate_per_kw, htlcs_and_sigs);
 
                for htlc in self.pending_inbound_htlcs.iter_mut() {
@@ -2646,7 +2657,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
 
                let our_funding_key = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()).serialize();
-               let their_funding_key = self.their_funding_pubkey.unwrap().serialize();
+               let their_funding_key = self.their_funding_pubkey().serialize();
                if our_funding_key[..] < their_funding_key[..] {
                        tx.input[0].witness.push(our_sig.serialize_der().to_vec());
                        tx.input[0].witness.push(their_sig.serialize_der().to_vec());
@@ -2681,14 +2692,16 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                }
                let mut sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
 
-               match self.secp_ctx.verify(&sighash, &msg.signature, &self.their_funding_pubkey.unwrap()) {
+               let their_funding_pubkey = &self.their_pubkeys.as_ref().unwrap().funding_pubkey;
+
+               match self.secp_ctx.verify(&sighash, &msg.signature, their_funding_pubkey) {
                        Ok(_) => {},
                        Err(_e) => {
                                // The remote end may have decided to revoke their output due to inconsistent dust
                                // limits, so check for that case by re-checking the signature here.
                                closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
                                sighash = hash_to_message!(&bip143::SighashComponents::new(&closing_tx).sighash_all(&closing_tx.input[0], &funding_redeemscript, self.channel_value_satoshis)[..]);
-                               secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, &self.their_funding_pubkey.unwrap()), "Invalid closing tx signature from peer");
+                               secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.their_funding_pubkey()), "Invalid closing tx signature from peer");
                        },
                };
 
@@ -3221,8 +3234,8 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                        short_channel_id: self.get_short_channel_id().unwrap(),
                        node_id_1: if were_node_one { our_node_id } else { self.get_their_node_id() },
                        node_id_2: if were_node_one { self.get_their_node_id() } else { our_node_id },
-                       bitcoin_key_1: if were_node_one { our_bitcoin_key } else { self.their_funding_pubkey.unwrap() },
-                       bitcoin_key_2: if were_node_one { self.their_funding_pubkey.unwrap() } else { our_bitcoin_key },
+                       bitcoin_key_1: if were_node_one { our_bitcoin_key } else { self.their_funding_pubkey().clone() },
+                       bitcoin_key_2: if were_node_one { self.their_funding_pubkey().clone() } else { our_bitcoin_key },
                        excess_data: Vec::new(),
                };
 
@@ -3785,11 +3798,7 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
                self.their_max_accepted_htlcs.write(writer)?;
                self.minimum_depth.write(writer)?;
 
-               write_option!(self.their_funding_pubkey);
-               write_option!(self.their_revocation_basepoint);
-               write_option!(self.their_payment_basepoint);
-               write_option!(self.their_delayed_payment_basepoint);
-               write_option!(self.their_htlc_basepoint);
+               write_option!(self.their_pubkeys);
                write_option!(self.their_cur_commitment_point);
 
                write_option!(self.their_prev_commitment_point);
@@ -3939,11 +3948,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
                let their_max_accepted_htlcs = Readable::read(reader)?;
                let minimum_depth = Readable::read(reader)?;
 
-               let their_funding_pubkey = Readable::read(reader)?;
-               let their_revocation_basepoint = Readable::read(reader)?;
-               let their_payment_basepoint = Readable::read(reader)?;
-               let their_delayed_payment_basepoint = Readable::read(reader)?;
-               let their_htlc_basepoint = Readable::read(reader)?;
+               let their_pubkeys = Readable::read(reader)?;
                let their_cur_commitment_point = Readable::read(reader)?;
 
                let their_prev_commitment_point = Readable::read(reader)?;
@@ -4016,11 +4021,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
                        their_max_accepted_htlcs,
                        minimum_depth,
 
-                       their_funding_pubkey,
-                       their_revocation_basepoint,
-                       their_payment_basepoint,
-                       their_delayed_payment_basepoint,
-                       their_htlc_basepoint,
+                       their_pubkeys,
                        their_cur_commitment_point,
 
                        their_prev_commitment_point,
@@ -4050,14 +4051,14 @@ mod tests {
        use ln::channel::{Channel,ChannelKeys,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,TxCreationKeys};
        use ln::channel::MAX_FUNDING_SATOSHIS;
        use ln::chan_utils;
-       use ln::chan_utils::LocalCommitmentTransaction;
+       use ln::chan_utils::{LocalCommitmentTransaction, ChannelPublicKeys};
        use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
        use chain::keysinterface::{InMemoryChannelKeys, KeysInterface};
        use chain::transaction::OutPoint;
        use util::config::UserConfig;
        use util::test_utils;
        use util::logger::Logger;
-       use secp256k1::{Secp256k1,Message,Signature};
+       use secp256k1::{Secp256k1, Message, Signature, All};
        use secp256k1::key::{SecretKey,PublicKey};
        use bitcoin_hashes::sha256::Hash as Sha256;
        use bitcoin_hashes::sha256d::Hash as Sha256dHash;
@@ -4105,6 +4106,10 @@ mod tests {
                fn get_channel_id(&self) -> [u8; 32] { [0; 32] }
        }
 
+       fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
+               PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
+       }
+
        #[test]
        fn outbound_commitment_test() {
                // Test vectors from BOLT 3 Appendix C:
@@ -4121,7 +4126,7 @@ mod tests {
                        // These aren't set in the test vectors:
                        revocation_base_key: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
                        commitment_seed: [0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
-                       remote_funding_pubkey: None,
+                       remote_channel_pubkeys: None,
                };
                assert_eq!(PublicKey::from_secret_key(&secp_ctx, chan_keys.funding_key()).serialize()[..],
                                hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
@@ -4137,19 +4142,22 @@ mod tests {
                let funding_info = OutPoint::new(Sha256dHash::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), 0);
                chan.channel_monitor.set_funding_info((funding_info, Script::new()));
 
-               chan.their_payment_basepoint = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("4444444444444444444444444444444444444444444444444444444444444444").unwrap()[..]).unwrap()));
-               assert_eq!(chan.their_payment_basepoint.unwrap().serialize()[..],
-                               hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
+               let their_pubkeys = ChannelPublicKeys {
+                       funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
+                       revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
+                       payment_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
+                       delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
+                       htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
+               };
 
-               chan.their_funding_pubkey = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13").unwrap()[..]).unwrap()));
-               assert_eq!(chan.their_funding_pubkey.unwrap().serialize()[..],
-                               hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
+               assert_eq!(their_pubkeys.payment_basepoint.serialize()[..],
+                          hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
 
-               chan.their_htlc_basepoint = Some(PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("4444444444444444444444444444444444444444444444444444444444444444").unwrap()[..]).unwrap()));
-               assert_eq!(chan.their_htlc_basepoint.unwrap().serialize()[..],
-                               hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
+               assert_eq!(their_pubkeys.funding_pubkey.serialize()[..],
+                          hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
 
-               chan.their_revocation_basepoint = Some(PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap());
+               assert_eq!(their_pubkeys.htlc_basepoint.serialize()[..],
+                          hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
 
                // We can't just use build_local_transaction_keys here as the per_commitment_secret is not
                // derived from a commitment_seed, so instead we copy it here and call
@@ -4158,7 +4166,9 @@ mod tests {
                let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
                let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
                let htlc_basepoint = PublicKey::from_secret_key(&secp_ctx, chan.local_keys.htlc_base_key());
-               let keys = TxCreationKeys::new(&secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &chan.their_revocation_basepoint.unwrap(), &chan.their_payment_basepoint.unwrap(), &chan.their_htlc_basepoint.unwrap()).unwrap();
+               let keys = TxCreationKeys::new(&secp_ctx, &per_commitment_point, &delayed_payment_base, &htlc_basepoint, &their_pubkeys.revocation_basepoint, &their_pubkeys.payment_basepoint, &their_pubkeys.htlc_basepoint).unwrap();
+
+               chan.their_pubkeys = Some(their_pubkeys);
 
                let mut unsigned_tx: (Transaction, Vec<HTLCOutputInCommitment>);
 
@@ -4174,9 +4184,9 @@ mod tests {
                                let redeemscript = chan.get_funding_redeemscript();
                                let their_signature = Signature::from_der(&hex::decode($their_sig_hex).unwrap()[..]).unwrap();
                                let sighash = Message::from_slice(&bip143::SighashComponents::new(&unsigned_tx.0).sighash_all(&unsigned_tx.0.input[0], &redeemscript, chan.channel_value_satoshis)[..]).unwrap();
-                               secp_ctx.verify(&sighash, &their_signature, &chan.their_funding_pubkey.unwrap()).unwrap();
+                               secp_ctx.verify(&sighash, &their_signature, chan.their_funding_pubkey()).unwrap();
 
-                               let mut localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), &their_signature, &PublicKey::from_secret_key(&secp_ctx, chan.local_keys.funding_key()), chan.their_funding_pubkey.as_ref().unwrap());
+                               let mut localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), &their_signature, &PublicKey::from_secret_key(&secp_ctx, chan.local_keys.funding_key()), chan.their_funding_pubkey());
                                localtx.add_local_sig(chan.local_keys.funding_key(), &redeemscript, chan.channel_value_satoshis, &chan.secp_ctx);
 
                                assert_eq!(serialize(localtx.with_valid_witness())[..],

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