X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Ffeatures.rs;h=79f869a4c5864761f6b1438ce8e3d6613e9e0a0a;hb=cf2c27800a1b30e72d4f7397c931cf6624594233;hp=6309eea413adb4d913c45379baad6eca16bdeb83;hpb=8e2b70d91a0f7322042d1b0935527c90c59afe45;p=rust-lightning diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs index 6309eea4..79f869a4 100644 --- a/lightning/src/ln/features.rs +++ b/lightning/src/ln/features.rs @@ -41,6 +41,12 @@ //! (see [BOLT-4](https://github.com/lightning/bolts/blob/master/04-onion-routing.md#basic-multi-part-payments) for more information). //! - `Wumbo` - requires/supports that a node create large channels. Called `option_support_large_channel` in the spec. //! (see [BOLT-2](https://github.com/lightning/bolts/blob/master/02-peer-protocol.md#the-open_channel-message) for more information). +//! - `AnchorsZeroFeeHtlcTx` - requires/supports that commitment transactions include anchor outputs +//! and HTLC transactions are pre-signed with zero fee (see +//! [BOLT-3](https://github.com/lightning/bolts/blob/master/03-transactions.md) for more +//! information). +//! - `RouteBlinding` - requires/supports that a node can relay payments over blinded paths +//! (see [BOLT-4](https://github.com/lightning/bolts/blob/master/04-onion-routing.md#route-blinding) for more information). //! - `ShutdownAnySegwit` - requires/supports that future segwit versions are allowed in `shutdown` //! (see [BOLT-2](https://github.com/lightning/bolts/blob/master/02-peer-protocol.md) for more information). //! - `OnionMessages` - requires/supports forwarding onion messages @@ -60,10 +66,6 @@ //! for more info). //! - `Keysend` - send funds to a node without an invoice //! (see the [`Keysend` feature assignment proposal](https://github.com/lightning/bolts/issues/605#issuecomment-606679798) for more information). -//! - `AnchorsZeroFeeHtlcTx` - requires/supports that commitment transactions include anchor outputs -//! and HTLC transactions are pre-signed with zero fee (see -//! [BOLT-3](https://github.com/lightning/bolts/blob/master/03-transactions.md) for more -//! information). //! //! LDK knows about the following features, but does not support them: //! - `AnchorsNonzeroFeeHtlcTx` - the initial version of anchor outputs, which was later found to be @@ -143,7 +145,7 @@ mod sealed { // Byte 2 BasicMPP | Wumbo | AnchorsNonzeroFeeHtlcTx | AnchorsZeroFeeHtlcTx, // Byte 3 - ShutdownAnySegwit, + RouteBlinding | ShutdownAnySegwit | Taproot, // Byte 4 OnionMessages, // Byte 5 @@ -159,7 +161,7 @@ mod sealed { // Byte 2 BasicMPP | Wumbo | AnchorsNonzeroFeeHtlcTx | AnchorsZeroFeeHtlcTx, // Byte 3 - ShutdownAnySegwit, + RouteBlinding | ShutdownAnySegwit | Taproot, // Byte 4 OnionMessages, // Byte 5 @@ -205,7 +207,7 @@ mod sealed { // Byte 2 AnchorsNonzeroFeeHtlcTx | AnchorsZeroFeeHtlcTx, // Byte 3 - , + Taproot, // Byte 4 , // Byte 5 @@ -391,9 +393,15 @@ mod sealed { define_feature!(23, AnchorsZeroFeeHtlcTx, [InitContext, NodeContext, ChannelTypeContext], "Feature flags for `option_anchors_zero_fee_htlc_tx`.", set_anchors_zero_fee_htlc_tx_optional, set_anchors_zero_fee_htlc_tx_required, supports_anchors_zero_fee_htlc_tx, requires_anchors_zero_fee_htlc_tx); + define_feature!(25, RouteBlinding, [InitContext, NodeContext], + "Feature flags for `option_route_blinding`.", set_route_blinding_optional, + set_route_blinding_required, supports_route_blinding, requires_route_blinding); define_feature!(27, ShutdownAnySegwit, [InitContext, NodeContext], "Feature flags for `opt_shutdown_anysegwit`.", set_shutdown_any_segwit_optional, set_shutdown_any_segwit_required, supports_shutdown_anysegwit, requires_shutdown_anysegwit); + define_feature!(31, Taproot, [InitContext, NodeContext, ChannelTypeContext], + "Feature flags for `option_taproot`.", set_taproot_optional, + set_taproot_required, supports_taproot, requires_taproot); define_feature!(39, OnionMessages, [InitContext, NodeContext], "Feature flags for `option_onion_messages`.", set_onion_messages_optional, set_onion_messages_required, supports_onion_messages, requires_onion_messages); @@ -461,12 +469,24 @@ impl Clone for Features { } impl Hash for Features { fn hash(&self, hasher: &mut H) { - self.flags.hash(hasher); + let mut nonzero_flags = &self.flags[..]; + while nonzero_flags.last() == Some(&0) { + nonzero_flags = &nonzero_flags[..nonzero_flags.len() - 1]; + } + nonzero_flags.hash(hasher); } } impl PartialEq for Features { fn eq(&self, o: &Self) -> bool { - self.flags.eq(&o.flags) + let mut o_iter = o.flags.iter(); + let mut self_iter = self.flags.iter(); + loop { + match (o_iter.next(), self_iter.next()) { + (Some(o), Some(us)) => if o != us { return false }, + (Some(b), None) | (None, Some(b)) => if *b != 0 { return false }, + (None, None) => return true, + } + } } } impl PartialOrd for Features { @@ -715,7 +735,11 @@ impl Features { Ok(()) } - fn from_be_bytes(mut flags: Vec) -> Features { + /// Create a [`Features`] given a set of flags, in big-endian. This is in byte order from + /// most on-the-wire encodings. + /// + /// This is not exported to bindings users as we don't support export across multiple T + pub fn from_be_bytes(mut flags: Vec) -> Features { flags.reverse(); // Swap to little-endian Self { flags, @@ -728,7 +752,7 @@ impl Features { } /// Returns true if this `Features` object contains required features unknown by `other`. - pub fn requires_unknown_bits_from(&self, other: &Features) -> bool { + pub fn requires_unknown_bits_from(&self, other: &Self) -> bool { // Bitwise AND-ing with all even bits set except for known features will select required // unknown features. self.flags.iter().enumerate().any(|(i, &byte)| { @@ -795,6 +819,35 @@ impl Features { true } + /// Sets a required feature bit. Errors if `bit` is outside the feature range as defined + /// by [BOLT 9]. + /// + /// Note: Required bits are even. If an odd bit is given, then the corresponding even bit will + /// be set instead (i.e., `bit - 1`). + /// + /// [BOLT 9]: https://github.com/lightning/bolts/blob/master/09-features.md + pub fn set_required_feature_bit(&mut self, bit: usize) -> Result<(), ()> { + self.set_feature_bit(bit - (bit % 2)) + } + + /// Sets an optional feature bit. Errors if `bit` is outside the feature range as defined + /// by [BOLT 9]. + /// + /// Note: Optional bits are odd. If an even bit is given, then the corresponding odd bit will be + /// set instead (i.e., `bit + 1`). + /// + /// [BOLT 9]: https://github.com/lightning/bolts/blob/master/09-features.md + pub fn set_optional_feature_bit(&mut self, bit: usize) -> Result<(), ()> { + self.set_feature_bit(bit + (1 - (bit % 2))) + } + + fn set_feature_bit(&mut self, bit: usize) -> Result<(), ()> { + if bit > 255 { + return Err(()); + } + self.set_bit(bit, false) + } + /// Sets a required custom feature bit. Errors if `bit` is outside the custom range as defined /// by [bLIP 2] or if it is a known `T` feature. /// @@ -821,10 +874,13 @@ impl Features { if bit < 256 { return Err(()); } + self.set_bit(bit, true) + } + fn set_bit(&mut self, bit: usize, custom: bool) -> Result<(), ()> { let byte_offset = bit / 8; let mask = 1 << (bit - 8 * byte_offset); - if byte_offset < T::KNOWN_FEATURE_MASK.len() { + if byte_offset < T::KNOWN_FEATURE_MASK.len() && custom { if (T::KNOWN_FEATURE_MASK[byte_offset] & mask) != 0 { return Err(()); } @@ -876,6 +932,13 @@ impl Features { } } +impl Features { + #[cfg(test)] + pub(crate) fn clear_route_blinding(&mut self) { + ::clear_bits(&mut self.flags); + } +} + #[cfg(test)] impl Features { pub(crate) fn unknown() -> Self { @@ -1014,6 +1077,7 @@ mod tests { init_features.set_basic_mpp_optional(); init_features.set_wumbo_optional(); init_features.set_anchors_zero_fee_htlc_tx_optional(); + init_features.set_route_blinding_optional(); init_features.set_shutdown_any_segwit_optional(); init_features.set_onion_messages_optional(); init_features.set_channel_type_optional(); @@ -1029,8 +1093,8 @@ mod tests { // Check that the flags are as expected: // - option_data_loss_protect (req) // - var_onion_optin (req) | static_remote_key (req) | payment_secret(req) - // - basic_mpp | wumbo | anchors_zero_fee_htlc_tx - // - opt_shutdown_anysegwit + // - basic_mpp | wumbo | option_anchors_zero_fee_htlc_tx + // - option_route_blinding | opt_shutdown_anysegwit // - onion_messages // - option_channel_type | option_scid_alias // - option_zeroconf @@ -1038,7 +1102,7 @@ mod tests { assert_eq!(node_features.flags[0], 0b00000001); assert_eq!(node_features.flags[1], 0b01010001); assert_eq!(node_features.flags[2], 0b10001010); - assert_eq!(node_features.flags[3], 0b00001000); + assert_eq!(node_features.flags[3], 0b00001010); assert_eq!(node_features.flags[4], 0b10000000); assert_eq!(node_features.flags[5], 0b10100000); assert_eq!(node_features.flags[6], 0b00001000); @@ -1075,6 +1139,13 @@ mod tests { assert!(!features.requires_basic_mpp()); assert!(features.requires_payment_secret()); assert!(features.supports_payment_secret()); + + // Set flags manually + let mut features = NodeFeatures::empty(); + assert!(features.set_optional_feature_bit(55).is_ok()); + assert!(features.supports_keysend()); + assert!(features.set_optional_feature_bit(255).is_ok()); + assert!(features.set_required_feature_bit(256).is_err()); } #[test] @@ -1163,4 +1234,26 @@ mod tests { assert!(!converted_features.supports_any_optional_bits()); assert!(converted_features.requires_static_remote_key()); } + + #[test] + #[cfg(feature = "std")] + fn test_excess_zero_bytes_ignored() { + // Checks that `Hash` and `PartialEq` ignore excess zero bytes, which may appear due to + // feature conversion or because a peer serialized their feature poorly. + use std::collections::hash_map::DefaultHasher; + use std::hash::{Hash, Hasher}; + + let mut zerod_features = InitFeatures::empty(); + zerod_features.flags = vec![0]; + let empty_features = InitFeatures::empty(); + assert!(empty_features.flags.is_empty()); + + assert_eq!(zerod_features, empty_features); + + let mut zerod_hash = DefaultHasher::new(); + zerod_features.hash(&mut zerod_hash); + let mut empty_hash = DefaultHasher::new(); + empty_features.hash(&mut empty_hash); + assert_eq!(zerod_hash.finish(), empty_hash.finish()); + } }