X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Ffeatures.rs;h=8f251d8478c7048f33cfb003725f4c94b388a209;hb=801d6e5256d6ac91d5d5668da1fa5a2b55303246;hp=5d908ee01a4957bd7c85d305043af8e5204523a2;hpb=d37b1dd6730535cebe0ce5d0434046848b244211;p=rust-lightning diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs index 5d908ee0..8f251d84 100644 --- a/lightning/src/ln/features.rs +++ b/lightning/src/ln/features.rs @@ -22,8 +22,10 @@ //! [BOLT #9]: https://github.com/lightningnetwork/lightning-rfc/blob/master/09-features.md //! [messages]: crate::ln::msgs +use io; use prelude::*; use core::{cmp, fmt}; +use core::hash::{Hash, Hasher}; use core::marker::PhantomData; use bitcoin::bech32; @@ -89,6 +91,28 @@ mod sealed { )* ]; } + + impl alloc::fmt::Display for Features<$context> { + fn fmt(&self, fmt: &mut alloc::fmt::Formatter) -> Result<(), alloc::fmt::Error> { + $( + $( + fmt.write_fmt(format_args!("{}: {}, ", stringify!($required_feature), + if <$context as $required_feature>::requires_feature(&self.flags) { "required" } + else if <$context as $required_feature>::supports_feature(&self.flags) { "supported" } + else { "not supported" }))?; + )* + $( + fmt.write_fmt(format_args!("{}: {}, ", stringify!($optional_feature), + if <$context as $optional_feature>::requires_feature(&self.flags) { "required" } + else if <$context as $optional_feature>::supports_feature(&self.flags) { "supported" } + else { "not supported" }))?; + )* + )* + fmt.write_fmt(format_args!("unknown flags: {}", + if self.requires_unknown_bits() { "required" } + else if self.supports_unknown_bits() { "supported" } else { "none" })) + } + } }; } @@ -124,6 +148,12 @@ mod sealed { , // Byte 3 , + // Byte 4 + , + // Byte 5 + , + // Byte 6 + , ], optional_features: [ // Byte 0 @@ -134,6 +164,12 @@ mod sealed { BasicMPP, // Byte 3 ShutdownAnySegwit, + // Byte 4 + , + // Byte 5 + , + // Byte 6 + Keysend, ], }); define_context!(ChannelContext { @@ -299,6 +335,8 @@ mod sealed { define_feature!(27, ShutdownAnySegwit, [InitContext, NodeContext], "Feature flags for `opt_shutdown_anysegwit`.", set_shutdown_any_segwit_optional, set_shutdown_any_segwit_required); + define_feature!(55, Keysend, [NodeContext], + "Feature flags for keysend payments.", set_keysend_optional, set_keysend_required); #[cfg(test)] define_feature!(123456789, UnknownFeature, [NodeContext, ChannelContext, InvoiceContext], @@ -325,6 +363,11 @@ impl Clone for Features { } } } +impl Hash for Features { + fn hash(&self, hasher: &mut H) { + self.flags.hash(hasher); + } +} impl PartialEq for Features { fn eq(&self, o: &Self) -> bool { self.flags.eq(&o.flags) @@ -347,9 +390,8 @@ pub type InvoiceFeatures = Features; impl InitFeatures { /// Writes all features present up to, and including, 13. - pub(crate) fn write_up_to_13(&self, w: &mut W) -> Result<(), ::std::io::Error> { + pub(crate) fn write_up_to_13(&self, w: &mut W) -> Result<(), io::Error> { let len = cmp::min(2, self.flags.len()); - w.size_hint(len + 2); (len as u16).write(w)?; for i in (0..len).rev() { if i == 0 { @@ -386,6 +428,18 @@ impl InvoiceFeatures { pub(crate) fn to_context(&self) -> Features { self.to_context_internal() } + + /// 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 + /// [`get_keysend_route`], thus omitting the need for payers to manually construct an + /// `InvoiceFeatures` for [`get_route`]. + /// + /// [`get_keysend_route`]: crate::routing::router::get_keysend_route + /// [`get_route`]: crate::routing::router::get_route + pub(crate) fn for_keysend() -> InvoiceFeatures { + InvoiceFeatures::empty().set_variable_length_onion_optional() + } } impl ToBase32 for InvoiceFeatures { @@ -499,7 +553,9 @@ impl Features { &self.flags } - pub(crate) fn requires_unknown_bits(&self) -> bool { + /// Returns true if this `Features` object contains unknown feature flags which are set as + /// "required". + pub fn requires_unknown_bits(&self) -> bool { // Bitwise AND-ing with all even bits set except for known features will select required // unknown features. let byte_count = T::KNOWN_FEATURE_MASK.len(); @@ -527,12 +583,6 @@ impl Features { (byte & unknown_features) != 0 }) } - - /// The number of bytes required to represent the feature flags present. This does not include - /// the length bytes which are included in the serialized form. - pub(crate) fn byte_count(&self) -> usize { - self.flags.len() - } } impl Features { @@ -540,6 +590,7 @@ impl Features { 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) } @@ -643,8 +694,7 @@ impl Features { } impl Writeable for Features { - fn write(&self, w: &mut W) -> Result<(), ::std::io::Error> { - w.size_hint(self.flags.len() + 2); + 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)?; @@ -654,7 +704,7 @@ impl Writeable for Features { } impl Readable for Features { - fn read(r: &mut R) -> Result { + fn read(r: &mut R) -> Result { let mut flags: Vec = Readable::read(r)?; flags.reverse(); // Swap to little-endian Ok(Self { @@ -777,7 +827,7 @@ mod tests { #[test] fn convert_to_context_with_unknown_flags() { // Ensure the `from` context has fewer known feature bytes than the `to` context. - assert!(InvoiceFeatures::known().byte_count() < NodeFeatures::known().byte_count()); + assert!(InvoiceFeatures::known().flags.len() < NodeFeatures::known().flags.len()); let invoice_features = InvoiceFeatures::known().set_unknown_feature_optional(); assert!(invoice_features.supports_unknown_bits()); let node_features: NodeFeatures = invoice_features.to_context();