X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Ffeatures.rs;h=a9f5a10ee2dad14395e18eda253cbaba2943106c;hb=06ecbecd6d5944281bbe1f1407114af49eb293d3;hp=259bda85eee7925f8f455058803fa850b3f29259;hpb=e6c922803f8d1f0303dd8a8f9300e32de55e1fc9;p=rust-lightning diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs index 259bda85..a9f5a10e 100644 --- a/lightning/src/ln/features.rs +++ b/lightning/src/ln/features.rs @@ -22,13 +22,17 @@ //! [BOLT #9]: https://github.com/lightningnetwork/lightning-rfc/blob/master/09-features.md //! [messages]: crate::ln::msgs -use std::{cmp, fmt}; -use std::marker::PhantomData; +use prelude::*; +use core::{cmp, fmt}; +use core::marker::PhantomData; +use bitcoin::bech32; +use bitcoin::bech32::{Base32Len, FromBase32, ToBase32, u5, WriteBase32}; use ln::msgs::DecodeError; use util::ser::{Readable, Writeable, Writer}; mod sealed { + use prelude::*; use ln::features::Features; /// The context in which [`Features`] are applicable. Defines which features are required and @@ -51,6 +55,7 @@ mod sealed { required_features: [$( $( $required_feature: ident )|*, )*], optional_features: [$( $( $optional_feature: ident )|*, )*], }) => { + #[derive(Eq, PartialEq)] pub struct $context {} impl Context for $context { @@ -92,7 +97,7 @@ mod sealed { // Byte 0 , // Byte 1 - StaticRemoteKey, + VariableLengthOnion | StaticRemoteKey | PaymentSecret, // Byte 2 , // Byte 3 @@ -102,7 +107,7 @@ mod sealed { // Byte 0 DataLossProtect | InitialRoutingSync | UpfrontShutdownScript | GossipQueries, // Byte 1 - VariableLengthOnion | PaymentSecret, + , // Byte 2 BasicMPP, // Byte 3 @@ -114,7 +119,7 @@ mod sealed { // Byte 0 , // Byte 1 - StaticRemoteKey, + VariableLengthOnion | StaticRemoteKey | PaymentSecret, // Byte 2 , // Byte 3 @@ -124,7 +129,7 @@ mod sealed { // Byte 0 DataLossProtect | UpfrontShutdownScript | GossipQueries, // Byte 1 - VariableLengthOnion | PaymentSecret, + , // Byte 2 BasicMPP, // Byte 3 @@ -136,13 +141,20 @@ mod sealed { optional_features: [], }); define_context!(InvoiceContext { - required_features: [,,,], - optional_features: [ + required_features: [ // Byte 0 , // Byte 1 VariableLengthOnion | PaymentSecret, // Byte 2 + , + ], + optional_features: [ + // Byte 0 + , + // Byte 1 + , + // Byte 2 BasicMPP, ], }); @@ -289,27 +301,7 @@ mod sealed { set_shutdown_any_segwit_required); #[cfg(test)] - define_context!(TestingContext { - required_features: [ - // Byte 0 - , - // Byte 1 - , - // Byte 2 - UnknownFeature, - ], - optional_features: [ - // Byte 0 - , - // Byte 1 - , - // Byte 2 - , - ], - }); - - #[cfg(test)] - define_feature!(23, UnknownFeature, [TestingContext], + define_feature!(123456789, UnknownFeature, [NodeContext, ChannelContext], "Feature flags for an unknown feature used in testing.", set_unknown_feature_optional, set_unknown_feature_required); } @@ -318,6 +310,7 @@ mod sealed { /// appears. /// /// (C-not exported) as we map the concrete feature types below directly instead +#[derive(Eq)] pub struct Features { /// Note that, for convenience, flags is LITTLE endian (despite being big-endian on the wire) flags: Vec, @@ -395,6 +388,68 @@ impl InvoiceFeatures { } } +impl ToBase32 for InvoiceFeatures { + fn write_base32(&self, writer: &mut W) -> Result<(), ::Err> { + // Explanation for the "4": the normal way to round up when dividing is to add the divisor + // minus one before dividing + let length_u5s = (self.flags.len() * 8 + 4) / 5 as usize; + let mut res_u5s: Vec = vec![u5::try_from_u8(0).unwrap(); length_u5s]; + for (byte_idx, byte) in self.flags.iter().enumerate() { + let bit_pos_from_left_0_indexed = byte_idx * 8; + let new_u5_idx = length_u5s - (bit_pos_from_left_0_indexed / 5) as usize - 1; + let new_bit_pos = bit_pos_from_left_0_indexed % 5; + let shifted_chunk_u16 = (*byte as u16) << new_bit_pos; + let curr_u5_as_u8 = res_u5s[new_u5_idx].to_u8(); + res_u5s[new_u5_idx] = u5::try_from_u8(curr_u5_as_u8 | ((shifted_chunk_u16 & 0x001f) as u8)).unwrap(); + if new_u5_idx > 0 { + let curr_u5_as_u8 = res_u5s[new_u5_idx - 1].to_u8(); + res_u5s[new_u5_idx - 1] = u5::try_from_u8(curr_u5_as_u8 | (((shifted_chunk_u16 >> 5) & 0x001f) as u8)).unwrap(); + } + if new_u5_idx > 1 { + let curr_u5_as_u8 = res_u5s[new_u5_idx - 2].to_u8(); + res_u5s[new_u5_idx - 2] = u5::try_from_u8(curr_u5_as_u8 | (((shifted_chunk_u16 >> 10) & 0x001f) as u8)).unwrap(); + } + } + // Trim the highest feature bits. + while !res_u5s.is_empty() && res_u5s[0] == u5::try_from_u8(0).unwrap() { + res_u5s.remove(0); + } + writer.write(&res_u5s) + } +} + +impl Base32Len for InvoiceFeatures { + fn base32_len(&self) -> usize { + self.to_base32().len() + } +} + +impl FromBase32 for InvoiceFeatures { + type Err = bech32::Error; + + fn from_base32(field_data: &[u5]) -> Result { + // Explanation for the "7": the normal way to round up when dividing is to add the divisor + // minus one before dividing + let length_bytes = (field_data.len() * 5 + 7) / 8 as usize; + let mut res_bytes: Vec = vec![0; length_bytes]; + for (u5_idx, chunk) in field_data.iter().enumerate() { + let bit_pos_from_right_0_indexed = (field_data.len() - u5_idx - 1) * 5; + let new_byte_idx = (bit_pos_from_right_0_indexed / 8) as usize; + let new_bit_pos = bit_pos_from_right_0_indexed % 8; + let chunk_u16 = chunk.to_u8() as u16; + res_bytes[new_byte_idx] |= ((chunk_u16 << new_bit_pos) & 0xff) as u8; + if new_byte_idx != length_bytes - 1 { + res_bytes[new_byte_idx + 1] |= ((chunk_u16 >> (8-new_bit_pos)) & 0xff) as u8; + } + } + // Trim the highest feature bits. + while !res_bytes.is_empty() && res_bytes[res_bytes.len() - 1] == 0 { + res_bytes.pop(); + } + Ok(InvoiceFeatures::from_le_bytes(res_bytes)) + } +} + impl Features { /// Create a blank Features with no features set pub fn empty() -> Self { @@ -415,20 +470,22 @@ impl Features { /// Converts `Features` to `Features`. Only known `T` features relevant to context `C` are /// included in the result. fn to_context_internal(&self) -> Features { - let byte_count = C::KNOWN_FEATURE_MASK.len(); + let from_byte_count = T::KNOWN_FEATURE_MASK.len(); + let to_byte_count = C::KNOWN_FEATURE_MASK.len(); let mut flags = Vec::new(); for (i, byte) in self.flags.iter().enumerate() { - if i < byte_count { - let known_source_features = T::KNOWN_FEATURE_MASK[i]; - let known_target_features = C::KNOWN_FEATURE_MASK[i]; - flags.push(byte & known_source_features & known_target_features); + if i < from_byte_count && i < to_byte_count { + let from_known_features = T::KNOWN_FEATURE_MASK[i]; + let to_known_features = C::KNOWN_FEATURE_MASK[i]; + flags.push(byte & from_known_features & to_known_features); } } Features:: { flags, mark: PhantomData, } } - #[cfg(test)] - /// Create a Features given a set of flags, in LE. + /// Create a Features given a set of flags, in little-endian. This is in reverse byte order from + /// most on-the-wire encodings. + /// (C-not exported) as we don't support export across multiple T pub fn from_le_bytes(flags: Vec) -> Features { Features { flags, @@ -476,21 +533,6 @@ impl Features { pub(crate) fn byte_count(&self) -> usize { self.flags.len() } - - #[cfg(test)] - pub(crate) fn set_required_unknown_bits(&mut self) { - ::set_required_bit(&mut self.flags); - } - - #[cfg(test)] - pub(crate) fn set_optional_unknown_bits(&mut self) { - ::set_optional_bit(&mut self.flags); - } - - #[cfg(test)] - pub(crate) fn clear_unknown_bits(&mut self) { - ::clear_bits(&mut self.flags); - } } impl Features { @@ -572,11 +614,8 @@ impl Features { pub(crate) fn requires_payment_secret(&self) -> bool { ::requires_feature(&self.flags) } - // Note that we never need to test this since what really matters is the invoice - iff the - // invoice provides a payment_secret, we assume that we can use it (ie that the recipient - // supports payment_secret). - #[allow(dead_code)] - pub(crate) fn supports_payment_secret(&self) -> bool { + /// Returns whether the `payment_secret` feature is supported. + pub fn supports_payment_secret(&self) -> bool { ::supports_feature(&self.flags) } } @@ -628,6 +667,7 @@ impl Readable for Features { #[cfg(test)] mod tests { use super::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures}; + use bitcoin::bech32::{Base32Len, FromBase32, ToBase32, u5}; #[test] fn sanity_test_known_features() { @@ -655,8 +695,10 @@ mod tests { assert!(InitFeatures::known().supports_variable_length_onion()); assert!(NodeFeatures::known().supports_variable_length_onion()); - assert!(!InitFeatures::known().requires_variable_length_onion()); - assert!(!NodeFeatures::known().requires_variable_length_onion()); + assert!(InvoiceFeatures::known().supports_variable_length_onion()); + assert!(InitFeatures::known().requires_variable_length_onion()); + assert!(NodeFeatures::known().requires_variable_length_onion()); + assert!(InvoiceFeatures::known().requires_variable_length_onion()); assert!(InitFeatures::known().supports_static_remote_key()); assert!(NodeFeatures::known().supports_static_remote_key()); @@ -665,13 +707,17 @@ mod tests { assert!(InitFeatures::known().supports_payment_secret()); assert!(NodeFeatures::known().supports_payment_secret()); - assert!(!InitFeatures::known().requires_payment_secret()); - assert!(!NodeFeatures::known().requires_payment_secret()); + assert!(InvoiceFeatures::known().supports_payment_secret()); + assert!(InitFeatures::known().requires_payment_secret()); + assert!(NodeFeatures::known().requires_payment_secret()); + assert!(InvoiceFeatures::known().requires_payment_secret()); assert!(InitFeatures::known().supports_basic_mpp()); assert!(NodeFeatures::known().supports_basic_mpp()); + assert!(InvoiceFeatures::known().supports_basic_mpp()); assert!(!InitFeatures::known().requires_basic_mpp()); assert!(!NodeFeatures::known().requires_basic_mpp()); + assert!(!InvoiceFeatures::known().requires_basic_mpp()); assert!(InitFeatures::known().supports_shutdown_anysegwit()); assert!(NodeFeatures::known().supports_shutdown_anysegwit()); @@ -684,19 +730,15 @@ mod tests { #[test] fn sanity_test_unknown_bits() { - let mut features = ChannelFeatures::empty(); + let features = ChannelFeatures::empty(); assert!(!features.requires_unknown_bits()); assert!(!features.supports_unknown_bits()); - features.set_required_unknown_bits(); + let features = ChannelFeatures::empty().set_unknown_feature_required(); assert!(features.requires_unknown_bits()); assert!(features.supports_unknown_bits()); - features.clear_unknown_bits(); - assert!(!features.requires_unknown_bits()); - assert!(!features.supports_unknown_bits()); - - features.set_optional_unknown_bits(); + let features = ChannelFeatures::empty().set_unknown_feature_optional(); assert!(!features.requires_unknown_bits()); assert!(features.supports_unknown_bits()); } @@ -712,12 +754,12 @@ mod tests { { // Check that the flags are as expected: // - option_data_loss_protect - // - var_onion_optin | static_remote_key (req) | payment_secret + // - var_onion_optin (req) | static_remote_key (req) | payment_secret(req) // - basic_mpp // - opt_shutdown_anysegwit assert_eq!(node_features.flags.len(), 4); assert_eq!(node_features.flags[0], 0b00000010); - assert_eq!(node_features.flags[1], 0b10010010); + assert_eq!(node_features.flags[1], 0b01010001); assert_eq!(node_features.flags[2], 0b00000010); assert_eq!(node_features.flags[3], 0b00001000); } @@ -742,4 +784,35 @@ mod tests { assert!(features.requires_payment_secret()); assert!(features.supports_payment_secret()); } + + #[test] + fn invoice_features_encoding() { + let features_as_u5s = vec![ + u5::try_from_u8(6).unwrap(), + u5::try_from_u8(10).unwrap(), + u5::try_from_u8(25).unwrap(), + u5::try_from_u8(1).unwrap(), + u5::try_from_u8(10).unwrap(), + u5::try_from_u8(0).unwrap(), + u5::try_from_u8(20).unwrap(), + u5::try_from_u8(2).unwrap(), + u5::try_from_u8(0).unwrap(), + u5::try_from_u8(6).unwrap(), + u5::try_from_u8(0).unwrap(), + u5::try_from_u8(16).unwrap(), + u5::try_from_u8(1).unwrap(), + ]; + let features = InvoiceFeatures::from_le_bytes(vec![1, 2, 3, 4, 5, 42, 100, 101]); + + // Test length calculation. + assert_eq!(features.base32_len(), 13); + + // Test serialization. + let features_serialized = features.to_base32(); + assert_eq!(features_as_u5s, features_serialized); + + // Test deserialization. + let features_deserialized = InvoiceFeatures::from_base32(&features_as_u5s).unwrap(); + assert_eq!(features, features_deserialized); + } }