X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Ffeatures.rs;h=2580874640e438e611bea9b88ddda0384dc9db5d;hb=5cfe19ef02cc9746ba664aeaa90921691a75dcd6;hp=888dcd3ac0c076f36eb8058712f8c708d4827d42;hpb=2d102a3065d7a438d5c88fffcad36545a0822bfa;p=rust-lightning diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs index 888dcd3a..25808746 100644 --- a/lightning/src/ln/features.rs +++ b/lightning/src/ln/features.rs @@ -22,7 +22,7 @@ //! [BOLT #9]: https://github.com/lightningnetwork/lightning-rfc/blob/master/09-features.md //! [messages]: crate::ln::msgs -use io; +use {io, io_extras}; use prelude::*; use core::{cmp, fmt}; use core::hash::{Hash, Hasher}; @@ -126,6 +126,10 @@ mod sealed { , // Byte 3 , + // Byte 4 + , + // Byte 5 + , ], optional_features: [ // Byte 0 @@ -133,9 +137,13 @@ mod sealed { // Byte 1 , // Byte 2 - BasicMPP, + BasicMPP | Wumbo, // Byte 3 ShutdownAnySegwit, + // Byte 4 + , + // Byte 5 + ChannelType | SCIDPrivacy, ], }); define_context!(NodeContext { @@ -161,13 +169,13 @@ mod sealed { // Byte 1 , // Byte 2 - BasicMPP, + BasicMPP | Wumbo, // Byte 3 ShutdownAnySegwit, // Byte 4 , // Byte 5 - , + ChannelType | SCIDPrivacy, // Byte 6 Keysend, ], @@ -194,12 +202,44 @@ mod sealed { BasicMPP, ], }); + // This isn't a "real" feature context, and is only used in the channel_type field in an + // `OpenChannel` message. + define_context!(ChannelTypeContext { + required_features: [ + // Byte 0 + , + // Byte 1 + StaticRemoteKey, + // Byte 2 + , + // Byte 3 + , + // Byte 4 + , + // Byte 5 + SCIDPrivacy, + ], + optional_features: [ + // Byte 0 + , + // Byte 1 + , + // Byte 2 + , + // Byte 3 + , + // Byte 4 + , + // Byte 5 + , + ], + }); /// Defines a feature with the given bits for the specified [`Context`]s. The generated trait is /// useful for manipulating feature flags. macro_rules! define_feature { ($odd_bit: expr, $feature: ident, [$($context: ty),+], $doc: expr, $optional_setter: ident, - $required_setter: ident) => { + $required_setter: ident, $supported_getter: ident) => { #[doc = $doc] /// /// See [BOLT #9] for details. @@ -286,15 +326,18 @@ mod sealed { impl Features { /// Set this feature as optional. - pub fn $optional_setter(mut self) -> Self { + pub fn $optional_setter(&mut self) { ::set_optional_bit(&mut self.flags); - self } /// Set this feature as required. - pub fn $required_setter(mut self) -> Self { + pub fn $required_setter(&mut self) { ::set_required_bit(&mut self.flags); - self + } + + /// Checks if this feature is supported. + pub fn $supported_getter(&self) -> bool { + ::supports_feature(&self.flags) } } @@ -307,41 +350,67 @@ mod sealed { const ASSERT_ODD_BIT_PARITY: usize = (::ODD_BIT % 2) - 1; } )* - + }; + ($odd_bit: expr, $feature: ident, [$($context: ty),+], $doc: expr, $optional_setter: ident, + $required_setter: ident, $supported_getter: ident, $required_getter: ident) => { + define_feature!($odd_bit, $feature, [$($context),+], $doc, $optional_setter, $required_setter, $supported_getter); + impl Features { + /// Checks if this feature is required. + pub fn $required_getter(&self) -> bool { + ::requires_feature(&self.flags) + } + } } } define_feature!(1, DataLossProtect, [InitContext, NodeContext], "Feature flags for `option_data_loss_protect`.", set_data_loss_protect_optional, - set_data_loss_protect_required); + set_data_loss_protect_required, supports_data_loss_protect, requires_data_loss_protect); // NOTE: Per Bolt #9, initial_routing_sync has no even bit. define_feature!(3, InitialRoutingSync, [InitContext], "Feature flags for `initial_routing_sync`.", - set_initial_routing_sync_optional, set_initial_routing_sync_required); + set_initial_routing_sync_optional, set_initial_routing_sync_required, + initial_routing_sync); define_feature!(5, UpfrontShutdownScript, [InitContext, NodeContext], "Feature flags for `option_upfront_shutdown_script`.", set_upfront_shutdown_script_optional, - set_upfront_shutdown_script_required); + set_upfront_shutdown_script_required, supports_upfront_shutdown_script, + requires_upfront_shutdown_script); define_feature!(7, GossipQueries, [InitContext, NodeContext], - "Feature flags for `gossip_queries`.", set_gossip_queries_optional, set_gossip_queries_required); + "Feature flags for `gossip_queries`.", set_gossip_queries_optional, set_gossip_queries_required, + supports_gossip_queries, requires_gossip_queries); define_feature!(9, VariableLengthOnion, [InitContext, NodeContext, InvoiceContext], "Feature flags for `var_onion_optin`.", set_variable_length_onion_optional, - set_variable_length_onion_required); - define_feature!(13, StaticRemoteKey, [InitContext, NodeContext], + set_variable_length_onion_required, supports_variable_length_onion, + requires_variable_length_onion); + define_feature!(13, StaticRemoteKey, [InitContext, NodeContext, ChannelTypeContext], "Feature flags for `option_static_remotekey`.", set_static_remote_key_optional, - set_static_remote_key_required); + set_static_remote_key_required, supports_static_remote_key, requires_static_remote_key); define_feature!(15, PaymentSecret, [InitContext, NodeContext, InvoiceContext], - "Feature flags for `payment_secret`.", set_payment_secret_optional, set_payment_secret_required); + "Feature flags for `payment_secret`.", set_payment_secret_optional, set_payment_secret_required, + supports_payment_secret, requires_payment_secret); define_feature!(17, BasicMPP, [InitContext, NodeContext, InvoiceContext], - "Feature flags for `basic_mpp`.", set_basic_mpp_optional, set_basic_mpp_required); + "Feature flags for `basic_mpp`.", set_basic_mpp_optional, set_basic_mpp_required, + supports_basic_mpp, requires_basic_mpp); + define_feature!(19, Wumbo, [InitContext, NodeContext], + "Feature flags for `option_support_large_channel` (aka wumbo channels).", set_wumbo_optional, set_wumbo_required, + supports_wumbo, requires_wumbo); define_feature!(27, ShutdownAnySegwit, [InitContext, NodeContext], "Feature flags for `opt_shutdown_anysegwit`.", set_shutdown_any_segwit_optional, - set_shutdown_any_segwit_required); + set_shutdown_any_segwit_required, supports_shutdown_anysegwit, requires_shutdown_anysegwit); + define_feature!(45, ChannelType, [InitContext, NodeContext], + "Feature flags for `option_channel_type`.", set_channel_type_optional, + set_channel_type_required, supports_channel_type, requires_channel_type); + define_feature!(47, SCIDPrivacy, [InitContext, NodeContext, ChannelTypeContext], + "Feature flags for only forwarding with SCID aliasing. Called `option_scid_alias` in the BOLTs", + set_scid_privacy_optional, set_scid_privacy_required, supports_scid_privacy, requires_scid_privacy); + define_feature!(55, Keysend, [NodeContext], - "Feature flags for keysend payments.", set_keysend_optional, set_keysend_required); + "Feature flags for keysend payments.", set_keysend_optional, set_keysend_required, + supports_keysend, requires_keysend); #[cfg(test)] define_feature!(123456789, UnknownFeature, [NodeContext, ChannelContext, InvoiceContext], "Feature flags for an unknown feature used in testing.", set_unknown_feature_optional, - set_unknown_feature_required); + set_unknown_feature_required, supports_unknown_test_feature, requires_unknown_test_feature); } /// Tracks the set of features which a node implements, templated by the context in which it @@ -388,6 +457,18 @@ pub type ChannelFeatures = Features; /// Features used within an invoice. pub type InvoiceFeatures = Features; +/// Features used within the channel_type field in an OpenChannel message. +/// +/// A channel is always of some known "type", describing the transaction formats used and the exact +/// semantics of our interaction with our peer. +/// +/// Note that because a channel is a specific type which is proposed by the opener and accepted by +/// the counterparty, only required features are allowed here. +/// +/// This is serialized differently from other feature types - it is not prefixed by a length, and +/// thus must only appear inside a TLV where its length is known in advance. +pub type ChannelTypeFeatures = Features; + impl InitFeatures { /// Writes all features present up to, and including, 13. pub(crate) fn write_up_to_13(&self, w: &mut W) -> Result<(), io::Error> { @@ -432,13 +513,37 @@ impl InvoiceFeatures { /// Getting a route for a keysend payment to a private node requires providing the payee's /// features (since they were not announced in a node announcement). However, keysend payments /// don't have an invoice to pull the payee's features from, so this method is provided for use in - /// [`Payee::for_keysend`], thus omitting the need for payers to manually construct an + /// [`PaymentParameters::for_keysend`], thus omitting the need for payers to manually construct an /// `InvoiceFeatures` for [`find_route`]. /// - /// [`Payee::for_keysend`]: crate::routing::router::Payee::for_keysend + /// [`PaymentParameters::for_keysend`]: crate::routing::router::PaymentParameters::for_keysend /// [`find_route`]: crate::routing::router::find_route pub(crate) fn for_keysend() -> InvoiceFeatures { - InvoiceFeatures::empty().set_variable_length_onion_optional() + let mut res = InvoiceFeatures::empty(); + res.set_variable_length_onion_optional(); + res + } +} + +impl ChannelTypeFeatures { + /// Constructs the implicit channel type based on the common supported types between us and our + /// counterparty + pub(crate) fn from_counterparty_init(counterparty_init: &InitFeatures) -> Self { + let mut ret = counterparty_init.to_context_internal(); + // ChannelTypeFeatures must only contain required bits, so we OR the required forms of all + // optional bits and then AND out the optional ones. + for byte in ret.flags.iter_mut() { + *byte |= (*byte & 0b10_10_10_10) >> 1; + *byte &= 0b01_01_01_01; + } + ret + } + + /// Constructs a ChannelTypeFeatures with only static_remotekey set + pub(crate) fn only_static_remote_key() -> Self { + let mut ret = Self::empty(); + ::set_required_bit(&mut ret.flags); + ret } } @@ -553,6 +658,25 @@ impl Features { &self.flags } + fn write_be(&self, w: &mut W) -> Result<(), io::Error> { + for f in self.flags.iter().rev() { // Swap back to big-endian + f.write(w)?; + } + Ok(()) + } + + fn from_be_bytes(mut flags: Vec) -> Features { + flags.reverse(); // Swap to little-endian + Self { + flags, + mark: PhantomData, + } + } + + pub(crate) fn supports_any_optional_bits(&self) -> bool { + self.flags.iter().any(|&byte| (byte & 0b10_10_10_10) != 0) + } + /// Returns true if this `Features` object contains unknown feature flags which are set as /// "required". pub fn requires_unknown_bits(&self) -> bool { @@ -585,25 +709,7 @@ impl Features { } } -impl Features { - #[cfg(test)] - pub(crate) fn requires_data_loss_protect(&self) -> bool { - ::requires_feature(&self.flags) - } - #[cfg(test)] - pub(crate) fn supports_data_loss_protect(&self) -> bool { - ::supports_feature(&self.flags) - } -} - impl Features { - #[cfg(test)] - pub(crate) fn requires_upfront_shutdown_script(&self) -> bool { - ::requires_feature(&self.flags) - } - pub(crate) fn supports_upfront_shutdown_script(&self) -> bool { - ::supports_feature(&self.flags) - } #[cfg(test)] pub(crate) fn clear_upfront_shutdown_script(mut self) -> Self { ::clear_bits(&mut self.flags); @@ -613,13 +719,6 @@ impl Features { impl Features { - #[cfg(test)] - pub(crate) fn requires_gossip_queries(&self) -> bool { - ::requires_feature(&self.flags) - } - pub(crate) fn supports_gossip_queries(&self) -> bool { - ::supports_feature(&self.flags) - } #[cfg(test)] pub(crate) fn clear_gossip_queries(mut self) -> Self { ::clear_bits(&mut self.flags); @@ -627,30 +726,7 @@ impl Features { } } -impl Features { - #[cfg(test)] - pub(crate) fn requires_variable_length_onion(&self) -> bool { - ::requires_feature(&self.flags) - } - pub(crate) fn supports_variable_length_onion(&self) -> bool { - ::supports_feature(&self.flags) - } -} - -impl Features { - pub(crate) fn supports_static_remote_key(&self) -> bool { - ::supports_feature(&self.flags) - } - #[cfg(test)] - pub(crate) fn requires_static_remote_key(&self) -> bool { - ::requires_feature(&self.flags) - } -} - impl Features { - pub(crate) fn initial_routing_sync(&self) -> bool { - ::supports_feature(&self.flags) - } // We are no longer setting initial_routing_sync now that gossip_queries // is enabled. This feature is ignored by a peer when gossip_queries has // been negotiated. @@ -660,63 +736,60 @@ impl Features { } } -impl Features { +impl Features { #[cfg(test)] - pub(crate) fn requires_payment_secret(&self) -> bool { - ::requires_feature(&self.flags) - } - /// Returns whether the `payment_secret` feature is supported. - pub fn supports_payment_secret(&self) -> bool { - ::supports_feature(&self.flags) + pub(crate) fn clear_shutdown_anysegwit(mut self) -> Self { + ::clear_bits(&mut self.flags); + self } } -impl Features { +impl Features { #[cfg(test)] - pub(crate) fn requires_basic_mpp(&self) -> bool { - ::requires_feature(&self.flags) - } - // We currently never test for this since we don't actually *generate* multipath routes. - pub(crate) fn supports_basic_mpp(&self) -> bool { - ::supports_feature(&self.flags) + pub(crate) fn clear_wumbo(mut self) -> Self { + ::clear_bits(&mut self.flags); + self } } -impl Features { - pub(crate) fn supports_shutdown_anysegwit(&self) -> bool { - ::supports_feature(&self.flags) - } - #[cfg(test)] - pub(crate) fn clear_shutdown_anysegwit(mut self) -> Self { - ::clear_bits(&mut self.flags); - self +macro_rules! impl_feature_len_prefixed_write { + ($features: ident) => { + impl Writeable for $features { + fn write(&self, w: &mut W) -> Result<(), io::Error> { + (self.flags.len() as u16).write(w)?; + self.write_be(w) + } + } + impl Readable for $features { + fn read(r: &mut R) -> Result { + Ok(Self::from_be_bytes(Vec::::read(r)?)) + } + } } } - -impl Writeable for Features { +impl_feature_len_prefixed_write!(InitFeatures); +impl_feature_len_prefixed_write!(ChannelFeatures); +impl_feature_len_prefixed_write!(NodeFeatures); +impl_feature_len_prefixed_write!(InvoiceFeatures); + +// Because ChannelTypeFeatures only appears inside of TLVs, it doesn't have a length prefix when +// serialized. Thus, we can't use `impl_feature_len_prefixed_write`, above, and have to write our +// own serialization. +impl Writeable for ChannelTypeFeatures { fn write(&self, w: &mut W) -> Result<(), io::Error> { - (self.flags.len() as u16).write(w)?; - for f in self.flags.iter().rev() { // Swap back to big-endian - f.write(w)?; - } - Ok(()) + self.write_be(w) } } - -impl Readable for Features { +impl Readable for ChannelTypeFeatures { fn read(r: &mut R) -> Result { - let mut flags: Vec = Readable::read(r)?; - flags.reverse(); // Swap to little-endian - Ok(Self { - flags, - mark: PhantomData, - }) + let v = io_extras::read_to_end(r)?; + Ok(Self::from_be_bytes(v)) } } #[cfg(test)] mod tests { - use super::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures}; + use super::{ChannelFeatures, ChannelTypeFeatures, InitFeatures, InvoiceFeatures, NodeFeatures}; use bitcoin::bech32::{Base32Len, FromBase32, ToBase32, u5}; #[test] @@ -769,9 +842,24 @@ mod tests { assert!(!NodeFeatures::known().requires_basic_mpp()); assert!(!InvoiceFeatures::known().requires_basic_mpp()); + assert!(InitFeatures::known().supports_channel_type()); + assert!(NodeFeatures::known().supports_channel_type()); + assert!(!InitFeatures::known().requires_channel_type()); + assert!(!NodeFeatures::known().requires_channel_type()); + assert!(InitFeatures::known().supports_shutdown_anysegwit()); assert!(NodeFeatures::known().supports_shutdown_anysegwit()); + assert!(InitFeatures::known().supports_scid_privacy()); + assert!(NodeFeatures::known().supports_scid_privacy()); + assert!(!InitFeatures::known().requires_scid_privacy()); + assert!(!NodeFeatures::known().requires_scid_privacy()); + + assert!(InitFeatures::known().supports_wumbo()); + assert!(NodeFeatures::known().supports_wumbo()); + assert!(!InitFeatures::known().requires_wumbo()); + assert!(!NodeFeatures::known().requires_wumbo()); + let mut init_features = InitFeatures::known(); assert!(init_features.initial_routing_sync()); init_features.clear_initial_routing_sync(); @@ -784,11 +872,13 @@ mod tests { assert!(!features.requires_unknown_bits()); assert!(!features.supports_unknown_bits()); - let features = ChannelFeatures::empty().set_unknown_feature_required(); + let mut features = ChannelFeatures::empty(); + features.set_unknown_feature_required(); assert!(features.requires_unknown_bits()); assert!(features.supports_unknown_bits()); - let features = ChannelFeatures::empty().set_unknown_feature_optional(); + let mut features = ChannelFeatures::empty(); + features.set_unknown_feature_optional(); assert!(!features.requires_unknown_bits()); assert!(features.supports_unknown_bits()); } @@ -805,13 +895,17 @@ mod tests { // Check that the flags are as expected: // - option_data_loss_protect // - var_onion_optin (req) | static_remote_key (req) | payment_secret(req) - // - basic_mpp + // - basic_mpp | wumbo // - opt_shutdown_anysegwit - assert_eq!(node_features.flags.len(), 4); + // - + // - option_channel_type | option_scid_alias + assert_eq!(node_features.flags.len(), 6); assert_eq!(node_features.flags[0], 0b00000010); assert_eq!(node_features.flags[1], 0b01010001); - assert_eq!(node_features.flags[2], 0b00000010); + assert_eq!(node_features.flags[2], 0b00001010); assert_eq!(node_features.flags[3], 0b00001000); + assert_eq!(node_features.flags[4], 0b00000000); + assert_eq!(node_features.flags[5], 0b10100000); } // Check that cleared flags are kept blank when converting back: @@ -828,7 +922,8 @@ mod tests { fn convert_to_context_with_unknown_flags() { // Ensure the `from` context has fewer known feature bytes than the `to` context. assert!(InvoiceFeatures::known().flags.len() < NodeFeatures::known().flags.len()); - let invoice_features = InvoiceFeatures::known().set_unknown_feature_optional(); + let mut invoice_features = InvoiceFeatures::known(); + invoice_features.set_unknown_feature_optional(); assert!(invoice_features.supports_unknown_bits()); let node_features: NodeFeatures = invoice_features.to_context(); assert!(!node_features.supports_unknown_bits()); @@ -836,9 +931,9 @@ mod tests { #[test] fn set_feature_bits() { - let features = InvoiceFeatures::empty() - .set_basic_mpp_optional() - .set_payment_secret_required(); + let mut features = InvoiceFeatures::empty(); + features.set_basic_mpp_optional(); + features.set_payment_secret_required(); assert!(features.supports_basic_mpp()); assert!(!features.requires_basic_mpp()); assert!(features.requires_payment_secret()); @@ -875,4 +970,16 @@ mod tests { let features_deserialized = InvoiceFeatures::from_base32(&features_as_u5s).unwrap(); assert_eq!(features, features_deserialized); } + + #[test] + fn test_channel_type_mapping() { + // If we map an InvoiceFeatures with StaticRemoteKey optional, it should map into a + // required-StaticRemoteKey ChannelTypeFeatures. + let mut init_features = InitFeatures::empty(); + init_features.set_static_remote_key_optional(); + let converted_features = ChannelTypeFeatures::from_counterparty_init(&init_features); + assert_eq!(converted_features, ChannelTypeFeatures::only_static_remote_key()); + assert!(!converted_features.supports_any_optional_bits()); + assert!(converted_features.requires_static_remote_key()); + } }