Verify channel type features for decoding.

[rust-lightning] / lightning / src / chain / package.rs

diff --git a/lightning/src/chain/package.rs b/lightning/src/chain/package.rs
index 0b7dbd462f47044561f5468693cfa9a27b68e8a1..891d7d1da33bddbeb8777c1349e1eda0a4c5a668 100644 (file)
--- a/lightning/src/chain/package.rs
+++ b/lightning/src/chain/package.rs
@@ -75,6 +75,30 @@ pub(crate) fn weight_received_htlc(channel_type_features: &ChannelTypeFeatures)
        if channel_type_features.supports_anchors_zero_fee_htlc_tx() { WEIGHT_RECEIVED_HTLC_ANCHORS } else { WEIGHT_RECEIVED_HTLC }
 }
 
+/// Verifies deserializable channel type features
+pub(crate) fn verify_channel_type_features(channel_type_features: &Option<ChannelTypeFeatures>, additional_permitted_features: Option<&ChannelTypeFeatures>) -> Result<(), DecodeError> {
+       if let Some(features) = channel_type_features.as_ref() {
+               if features.requires_unknown_bits() {
+                       return Err(DecodeError::UnknownRequiredFeature);
+               }
+
+               let mut supported_feature_set = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
+               supported_feature_set.set_scid_privacy_required();
+               supported_feature_set.set_zero_conf_required();
+
+               // allow the passing of an additional necessary permitted flag
+               if let Some(additional_permitted_features) = additional_permitted_features {
+                       supported_feature_set |= additional_permitted_features;
+               }
+
+               if !features.is_subset(&supported_feature_set) {
+                       return Err(DecodeError::UnknownRequiredFeature);
+               }
+       }
+
+       Ok(())
+}
+
 // number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script
 pub(crate) const WEIGHT_REVOKED_OUTPUT: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 77;
 
@@ -239,6 +263,8 @@ impl Readable for CounterpartyOfferedHTLCOutput {
                        (11, channel_type_features, option),
                });
 
+               verify_channel_type_features(&channel_type_features, None)?;
+
                Ok(Self {
                        per_commitment_point: per_commitment_point.0.unwrap(),
                        counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
@@ -310,6 +336,8 @@ impl Readable for CounterpartyReceivedHTLCOutput {
                        (9, channel_type_features, option),
                });
 
+               verify_channel_type_features(&channel_type_features, None)?;
+
                Ok(Self {
                        per_commitment_point: per_commitment_point.0.unwrap(),
                        counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
@@ -385,6 +413,8 @@ impl Readable for HolderHTLCOutput {
                        (7, channel_type_features, option),
                });
 
+               verify_channel_type_features(&channel_type_features, None)?;
+
                Ok(Self {
                        amount_msat: amount_msat.0.unwrap(),
                        cltv_expiry: cltv_expiry.0.unwrap(),
@@ -444,6 +474,8 @@ impl Readable for HolderFundingOutput {
                        (3, funding_amount, option)
                });
 
+               verify_channel_type_features(&channel_type_features, None)?;
+
                Ok(Self {
                        funding_redeemscript: funding_redeemscript.0.unwrap(),
                        channel_type_features: channel_type_features.unwrap_or(ChannelTypeFeatures::only_static_remote_key()),