Let some tests disable revocation policy check

[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 af497cbbe5bf2c65675873cd83c2ff96adcbef09..88c1754f13599162b185350612b2b2f03abcd87a 100644 (file)
--- a/lightning/src/util/enforcing_trait_impls.rs
+++ b/lightning/src/util/enforcing_trait_impls.rs
@@ -27,31 +27,49 @@ use ln::msgs::DecodeError;
 /// Initial value for revoked commitment downward counter
 pub const INITIAL_REVOKED_COMMITMENT_NUMBER: u64 = 1 << 48;
 
-/// An implementation of ChannelKeys that enforces some policy checks.
+/// An implementation of ChannelKeys that enforces some policy checks.  The current checks
+/// are an incomplete set.  They include:
+///
+/// - When signing, the holder transaction has not been revoked
+/// - When revoking, the holder transaction has not been signed
+/// - The holder commitment number is monotonic and without gaps
+/// - The counterparty commitment number is monotonic and without gaps
+/// - The pre-derived keys and pre-built transaction in CommitmentTransaction were correctly built
 ///
 /// Eventually we will probably want to expose a variant of this which would essentially
 /// be what you'd want to run on a hardware wallet.
 #[derive(Clone)]
 pub struct EnforcingChannelKeys {
        pub inner: InMemoryChannelKeys,
+       /// The last counterparty commitment number we signed, backwards counting
        pub last_commitment_number: Arc<Mutex<Option<u64>>>,
+       /// The last holder commitment number we revoked, backwards counting
        pub revoked_commitment: Arc<Mutex<u64>>,
+       pub disable_revocation_policy_check: bool,
 }
 
 impl EnforcingChannelKeys {
+       /// Construct an EnforcingChannelKeys
        pub fn new(inner: InMemoryChannelKeys) -> Self {
                Self {
                        inner,
                        last_commitment_number: Arc::new(Mutex::new(None)),
-                       revoked_commitment: Arc::new(Mutex::new(INITIAL_REVOKED_COMMITMENT_NUMBER))
+                       revoked_commitment: Arc::new(Mutex::new(INITIAL_REVOKED_COMMITMENT_NUMBER)),
+                       disable_revocation_policy_check: false
                }
        }
 
-       pub fn new_with_revoked(inner: InMemoryChannelKeys, revoked_commitment: Arc<Mutex<u64>>) -> Self {
+       /// Construct an EnforcingChannelKeys with externally managed storage
+       ///
+       /// Since there are multiple copies of this struct for each channel, some coordination is needed
+       /// so that all copies are aware of revocations.  A pointer to this state is provided here, usually
+       /// by an implementation of KeysInterface.
+       pub fn new_with_revoked(inner: InMemoryChannelKeys, revoked_commitment: Arc<Mutex<u64>>, disable_revocation_policy_check: bool) -> Self {
                Self {
                        inner,
                        last_commitment_number: Arc::new(Mutex::new(None)),
-                       revoked_commitment
+                       revoked_commitment,
+                       disable_revocation_policy_check
                }
        }
 }
@@ -62,8 +80,6 @@ impl ChannelKeys for EnforcingChannelKeys {
        }
 
        fn release_commitment_secret(&self, idx: u64) -> [u8; 32] {
-               println!("XXX revoke {} for {}", idx, self.inner.commitment_seed[0]);
-
                {
                        let mut revoked = self.revoked_commitment.lock().unwrap();
                        assert!(idx == *revoked || idx == *revoked - 1, "can only revoke the current or next unrevoked commitment - trying {}, revoked {}", idx, *revoked);
@@ -98,11 +114,11 @@ impl ChannelKeys for EnforcingChannelKeys {
 
                let revoked = self.revoked_commitment.lock().unwrap();
                let commitment_number = trusted_tx.commitment_number();
-               println!("XXX sign {} for {}", commitment_number, self.inner.commitment_seed[0]);
                if *revoked - 1 != commitment_number && *revoked - 2 != commitment_number {
-                       println!("can only sign the next two unrevoked commitment numbers, revoked={} vs requested={} for {}",
-                                *revoked, commitment_number, self.inner.commitment_seed[0]);
-                       return Err(());
+                       if !self.disable_revocation_policy_check {
+                               panic!("can only sign the next two unrevoked commitment numbers, revoked={} vs requested={} for {}",
+                                      *revoked, commitment_number, self.inner.commitment_seed[0])
+                       }
                }
 
                for (this_htlc, sig) in trusted_tx.htlcs().iter().zip(&commitment_tx.counterparty_htlc_sigs) {
@@ -116,8 +132,6 @@ impl ChannelKeys for EnforcingChannelKeys {
                        secp_ctx.verify(&sighash, sig, &keys.countersignatory_htlc_key).unwrap();
                }
 
-               // TODO: enforce the ChannelKeys contract - error if this commitment was already revoked
-               // TODO: need the commitment number
                Ok(self.inner.sign_holder_commitment_and_htlcs(commitment_tx, secp_ctx).unwrap())
        }
 
@@ -159,12 +173,13 @@ impl Writeable for EnforcingChannelKeys {
 
 impl Readable for EnforcingChannelKeys {
        fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
-               let inner: InMemoryChannelKeys = Readable::read(reader)?;
+               let inner = Readable::read(reader)?;
                let last_commitment_number = Readable::read(reader)?;
                Ok(EnforcingChannelKeys {
                        inner,
                        last_commitment_number: Arc::new(Mutex::new(last_commitment_number)),
                        revoked_commitment: Arc::new(Mutex::new(INITIAL_REVOKED_COMMITMENT_NUMBER)),
+                       disable_revocation_policy_check: false,
                })
        }
 }