+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
//! Feature flag definitions for the Lightning protocol according to [BOLT #9].
//!
//! Lightning nodes advertise a supported set of operation through feature flags. Features are
//! applicable for a specific context as indicated in some [messages]. [`Features`] encapsulates
//! behavior for specifying and checking feature flags for a particular context. Each feature is
-//! defined internally by a trait specifying the corresponding flags (i.e., even and odd bits). A
-//! [`Context`] is used to parameterize [`Features`] and defines which features it can support.
+//! defined internally by a trait specifying the corresponding flags (i.e., even and odd bits).
+//!
+//! Whether a feature is considered "known" or "unknown" is relative to the implementation, whereas
+//! the term "supports" is used in reference to a particular set of [`Features`]. That is, a node
+//! supports a feature if it advertises the feature (as either required or optional) to its peers.
+//! And the implementation can interpret a feature if the feature is known to it.
//!
//! [BOLT #9]: https://github.com/lightningnetwork/lightning-rfc/blob/master/09-features.md
-//! [messages]: ../msgs/index.html
-//! [`Features`]: struct.Features.html
-//! [`Context`]: sealed/trait.Context.html
+//! [messages]: crate::ln::msgs
-use std::{cmp, fmt};
-use std::result::Result;
-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};
-#[macro_use]
-mod sealed { // You should just use the type aliases instead.
- pub struct InitContext {}
- pub struct NodeContext {}
- pub struct ChannelContext {}
+mod sealed {
+ use prelude::*;
+ use ln::features::Features;
+
+ /// The context in which [`Features`] are applicable. Defines which features are required and
+ /// which are optional for the context.
+ pub trait Context {
+ /// Features that are known to the implementation, where a required feature is indicated by
+ /// its even bit and an optional feature is indicated by its odd bit.
+ const KNOWN_FEATURE_FLAGS: &'static [u8];
+
+ /// Bitmask for selecting features that are known to the implementation, regardless of
+ /// whether each feature is required or optional.
+ const KNOWN_FEATURE_MASK: &'static [u8];
+ }
+
+ /// Defines a [`Context`] by stating which features it requires and which are optional. Features
+ /// are specified as a comma-separated list of bytes where each byte is a pipe-delimited list of
+ /// feature identifiers.
+ macro_rules! define_context {
+ ($context: ident {
+ required_features: [$( $( $required_feature: ident )|*, )*],
+ optional_features: [$( $( $optional_feature: ident )|*, )*],
+ }) => {
+ #[derive(Eq, PartialEq)]
+ pub struct $context {}
+
+ impl Context for $context {
+ const KNOWN_FEATURE_FLAGS: &'static [u8] = &[
+ // For each byte, use bitwise-OR to compute the applicable flags for known
+ // required features `r_i` and optional features `o_j` for all `i` and `j` such
+ // that the following slice is formed:
+ //
+ // [
+ // `r_0` | `r_1` | ... | `o_0` | `o_1` | ...,
+ // ...,
+ // ]
+ $(
+ 0b00_00_00_00 $(|
+ <Self as $required_feature>::REQUIRED_MASK)*
+ $(|
+ <Self as $optional_feature>::OPTIONAL_MASK)*,
+ )*
+ ];
- /// An internal trait capturing the various feature context types
- pub trait Context {}
- impl Context for InitContext {}
- impl Context for NodeContext {}
- impl Context for ChannelContext {}
+ const KNOWN_FEATURE_MASK: &'static [u8] = &[
+ // Similar as above, but set both flags for each feature regardless of whether
+ // the feature is required or optional.
+ $(
+ 0b00_00_00_00 $(|
+ <Self as $required_feature>::REQUIRED_MASK |
+ <Self as $required_feature>::OPTIONAL_MASK)*
+ $(|
+ <Self as $optional_feature>::REQUIRED_MASK |
+ <Self as $optional_feature>::OPTIONAL_MASK)*,
+ )*
+ ];
+ }
+ };
+ }
+
+ define_context!(InitContext {
+ required_features: [
+ // Byte 0
+ ,
+ // Byte 1
+ VariableLengthOnion | StaticRemoteKey | PaymentSecret,
+ // Byte 2
+ ,
+ // Byte 3
+ ,
+ ],
+ optional_features: [
+ // Byte 0
+ DataLossProtect | InitialRoutingSync | UpfrontShutdownScript | GossipQueries,
+ // Byte 1
+ ,
+ // Byte 2
+ BasicMPP,
+ // Byte 3
+ ShutdownAnySegwit,
+ ],
+ });
+ define_context!(NodeContext {
+ required_features: [
+ // Byte 0
+ ,
+ // Byte 1
+ VariableLengthOnion | StaticRemoteKey | PaymentSecret,
+ // Byte 2
+ ,
+ // Byte 3
+ ,
+ ],
+ optional_features: [
+ // Byte 0
+ DataLossProtect | UpfrontShutdownScript | GossipQueries,
+ // Byte 1
+ ,
+ // Byte 2
+ BasicMPP,
+ // Byte 3
+ ShutdownAnySegwit,
+ ],
+ });
+ define_context!(ChannelContext {
+ required_features: [],
+ optional_features: [],
+ });
+ define_context!(InvoiceContext {
+ required_features: [
+ // Byte 0
+ ,
+ // Byte 1
+ VariableLengthOnion | PaymentSecret,
+ // Byte 2
+ ,
+ ],
+ optional_features: [
+ // Byte 0
+ ,
+ // Byte 1
+ ,
+ // Byte 2
+ BasicMPP,
+ ],
+ });
/// Defines a feature with the given bits for the specified [`Context`]s. The generated trait is
/// useful for manipulating feature flags.
- ///
- /// [`Context`]: trait.Context.html
macro_rules! define_feature {
- ($odd_bit: expr, $feature: ident, [$($context: ty),+], $doc: expr) => {
+ ($odd_bit: expr, $feature: ident, [$($context: ty),+], $doc: expr, $optional_setter: ident,
+ $required_setter: ident) => {
#[doc = $doc]
///
/// See [BOLT #9] for details.
/// [`BYTE_OFFSET`]: #associatedconstant.BYTE_OFFSET
const OPTIONAL_MASK: u8 = 1 << (Self::ODD_BIT - 8 * Self::BYTE_OFFSET);
+ /// Returns whether the feature is required by the given flags.
+ #[inline]
+ fn requires_feature(flags: &Vec<u8>) -> bool {
+ flags.len() > Self::BYTE_OFFSET &&
+ (flags[Self::BYTE_OFFSET] & Self::REQUIRED_MASK) != 0
+ }
+
/// Returns whether the feature is supported by the given flags.
#[inline]
fn supports_feature(flags: &Vec<u8>) -> bool {
(flags[Self::BYTE_OFFSET] & (Self::REQUIRED_MASK | Self::OPTIONAL_MASK)) != 0
}
+ /// Sets the feature's required (even) bit in the given flags.
+ #[inline]
+ fn set_required_bit(flags: &mut Vec<u8>) {
+ if flags.len() <= Self::BYTE_OFFSET {
+ flags.resize(Self::BYTE_OFFSET + 1, 0u8);
+ }
+
+ flags[Self::BYTE_OFFSET] |= Self::REQUIRED_MASK;
+ }
+
/// Sets the feature's optional (odd) bit in the given flags.
#[inline]
fn set_optional_bit(flags: &mut Vec<u8>) {
flags[Self::BYTE_OFFSET] |= Self::OPTIONAL_MASK;
}
- /// Clears the feature's optional (odd) bit from the given flags.
+ /// Clears the feature's required (even) and optional (odd) bits from the given
+ /// flags.
#[inline]
- fn clear_optional_bit(flags: &mut Vec<u8>) {
+ fn clear_bits(flags: &mut Vec<u8>) {
if flags.len() > Self::BYTE_OFFSET {
+ flags[Self::BYTE_OFFSET] &= !Self::REQUIRED_MASK;
flags[Self::BYTE_OFFSET] &= !Self::OPTIONAL_MASK;
}
+
+ let last_non_zero_byte = flags.iter().rposition(|&byte| byte != 0);
+ let size = if let Some(offset) = last_non_zero_byte { offset + 1 } else { 0 };
+ flags.resize(size, 0u8);
+ }
+ }
+
+ impl <T: $feature> Features<T> {
+ /// Set this feature as optional.
+ pub fn $optional_setter(mut self) -> Self {
+ <T as $feature>::set_optional_bit(&mut self.flags);
+ self
+ }
+
+ /// Set this feature as required.
+ pub fn $required_setter(mut self) -> Self {
+ <T as $feature>::set_required_bit(&mut self.flags);
+ self
}
}
const ASSERT_ODD_BIT_PARITY: usize = (<Self as $feature>::ODD_BIT % 2) - 1;
}
)*
+
}
}
define_feature!(1, DataLossProtect, [InitContext, NodeContext],
- "Feature flags for `option_data_loss_protect`.");
+ "Feature flags for `option_data_loss_protect`.", set_data_loss_protect_optional,
+ set_data_loss_protect_required);
// NOTE: Per Bolt #9, initial_routing_sync has no even bit.
- define_feature!(3, InitialRoutingSync, [InitContext],
- "Feature flags for `initial_routing_sync`.");
+ define_feature!(3, InitialRoutingSync, [InitContext], "Feature flags for `initial_routing_sync`.",
+ set_initial_routing_sync_optional, set_initial_routing_sync_required);
define_feature!(5, UpfrontShutdownScript, [InitContext, NodeContext],
- "Feature flags for `option_upfront_shutdown_script`.");
- define_feature!(9, VariableLengthOnion, [InitContext, NodeContext],
- "Feature flags for `var_onion_optin`.");
- define_feature!(15, PaymentSecret, [InitContext, NodeContext],
- "Feature flags for `payment_secret`.");
- define_feature!(17, BasicMPP, [InitContext, NodeContext],
- "Feature flags for `basic_mpp`.");
-
- /// Generates a feature flag byte with the given features set as optional. Useful for initializing
- /// the flags within [`Features`].
- ///
- /// [`Features`]: struct.Features.html
- macro_rules! feature_flags {
- ($context: ty; $($feature: ident)|*) => {
- (0b00_00_00_00
- $(
- | <$context as sealed::$feature>::OPTIONAL_MASK
- )*
- )
- }
- }
+ "Feature flags for `option_upfront_shutdown_script`.", set_upfront_shutdown_script_optional,
+ set_upfront_shutdown_script_required);
+ define_feature!(7, GossipQueries, [InitContext, NodeContext],
+ "Feature flags for `gossip_queries`.", set_gossip_queries_optional, set_gossip_queries_required);
+ 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],
+ "Feature flags for `option_static_remotekey`.", set_static_remote_key_optional,
+ set_static_remote_key_required);
+ define_feature!(15, PaymentSecret, [InitContext, NodeContext, InvoiceContext],
+ "Feature flags for `payment_secret`.", set_payment_secret_optional, set_payment_secret_required);
+ define_feature!(17, BasicMPP, [InitContext, NodeContext, InvoiceContext],
+ "Feature flags for `basic_mpp`.", set_basic_mpp_optional, set_basic_mpp_required);
+ define_feature!(27, ShutdownAnySegwit, [InitContext, NodeContext],
+ "Feature flags for `opt_shutdown_anysegwit`.", set_shutdown_any_segwit_optional,
+ 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],
+ "Feature flags for an unknown feature used in testing.", set_unknown_feature_optional,
+ set_unknown_feature_required);
}
/// Tracks the set of features which a node implements, templated by the context in which it
/// appears.
+///
+/// (C-not exported) as we map the concrete feature types below directly instead
+#[derive(Eq)]
pub struct Features<T: sealed::Context> {
/// Note that, for convenience, flags is LITTLE endian (despite being big-endian on the wire)
flags: Vec<u8>,
pub type NodeFeatures = Features<sealed::NodeContext>;
/// Features used within a `channel_announcement` message.
pub type ChannelFeatures = Features<sealed::ChannelContext>;
+/// Features used within an invoice.
+pub type InvoiceFeatures = Features<sealed::InvoiceContext>;
impl InitFeatures {
- /// Create a Features with the features we support
- pub fn supported() -> InitFeatures {
- InitFeatures {
- flags: vec![
- feature_flags![sealed::InitContext; DataLossProtect | InitialRoutingSync | UpfrontShutdownScript],
- feature_flags![sealed::InitContext; VariableLengthOnion | PaymentSecret],
- feature_flags![sealed::InitContext; BasicMPP],
- ],
- mark: PhantomData,
- }
- }
-
/// Writes all features present up to, and including, 13.
pub(crate) fn write_up_to_13<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
let len = cmp::min(2, self.flags.len());
}
self
}
-}
-impl ChannelFeatures {
- /// Create a Features with the features we support
- #[cfg(not(feature = "fuzztarget"))]
- pub(crate) fn supported() -> ChannelFeatures {
- ChannelFeatures {
- flags: Vec::new(),
- mark: PhantomData,
- }
- }
- #[cfg(feature = "fuzztarget")]
- pub fn supported() -> ChannelFeatures {
- ChannelFeatures {
- flags: Vec::new(),
- mark: PhantomData,
- }
+ /// Converts `InitFeatures` to `Features<C>`. Only known `InitFeatures` relevant to context `C`
+ /// are included in the result.
+ pub(crate) fn to_context<C: sealed::Context>(&self) -> Features<C> {
+ self.to_context_internal()
}
+}
- /// Takes the flags that we know how to interpret in an init-context features that are also
- /// relevant in a channel-context features and creates a channel-context features from them.
- pub(crate) fn with_known_relevant_init_flags(_init_ctx: &InitFeatures) -> Self {
- // There are currently no channel flags defined that we understand.
- Self { flags: Vec::new(), mark: PhantomData, }
+impl InvoiceFeatures {
+ /// Converts `InvoiceFeatures` to `Features<C>`. Only known `InvoiceFeatures` relevant to
+ /// context `C` are included in the result.
+ pub(crate) fn to_context<C: sealed::Context>(&self) -> Features<C> {
+ self.to_context_internal()
}
}
-impl NodeFeatures {
- /// Create a Features with the features we support
- #[cfg(not(feature = "fuzztarget"))]
- pub(crate) fn supported() -> NodeFeatures {
- NodeFeatures {
- flags: vec![
- feature_flags![sealed::NodeContext; DataLossProtect | UpfrontShutdownScript],
- feature_flags![sealed::NodeContext; VariableLengthOnion | PaymentSecret],
- feature_flags![sealed::NodeContext; BasicMPP],
- ],
- mark: PhantomData,
+impl ToBase32 for InvoiceFeatures {
+ fn write_base32<W: WriteBase32>(&self, writer: &mut W) -> Result<(), <W as WriteBase32>::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<u5> = 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();
+ }
}
- }
- #[cfg(feature = "fuzztarget")]
- pub fn supported() -> NodeFeatures {
- NodeFeatures {
- flags: vec![
- feature_flags![sealed::NodeContext; DataLossProtect | UpfrontShutdownScript],
- feature_flags![sealed::NodeContext; VariableLengthOnion | PaymentSecret],
- feature_flags![sealed::NodeContext; BasicMPP],
- ],
- mark: PhantomData,
+ // 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)
}
+}
- /// Takes the flags that we know how to interpret in an init-context features that are also
- /// relevant in a node-context features and creates a node-context features from them.
- /// Be sure to blank out features that are unknown to us.
- pub(crate) fn with_known_relevant_init_flags(init_ctx: &InitFeatures) -> Self {
- // Generates a bitmask with both even and odd bits set for the given features. Bitwise
- // AND-ing it with a byte will select only common features.
- macro_rules! features_including {
- ($($feature: ident)|*) => {
- (0b00_00_00_00
- $(
- | <sealed::NodeContext as sealed::$feature>::REQUIRED_MASK
- | <sealed::NodeContext as sealed::$feature>::OPTIONAL_MASK
- )*
- )
- }
- }
+impl Base32Len for InvoiceFeatures {
+ fn base32_len(&self) -> usize {
+ self.to_base32().len()
+ }
+}
- let mut flags = Vec::new();
- for (i, feature_byte)in init_ctx.flags.iter().enumerate() {
- match i {
- 0 => flags.push(feature_byte & features_including![DataLossProtect | UpfrontShutdownScript]),
- 1 => flags.push(feature_byte & features_including![VariableLengthOnion | PaymentSecret]),
- 2 => flags.push(feature_byte & features_including![BasicMPP]),
- _ => (),
+impl FromBase32 for InvoiceFeatures {
+ type Err = bech32::Error;
+
+ fn from_base32(field_data: &[u5]) -> Result<InvoiceFeatures, bech32::Error> {
+ // 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<u8> = 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;
}
}
- Self { flags, mark: PhantomData, }
+ // 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<T: sealed::Context> Features<T> {
/// Create a blank Features with no features set
- pub fn empty() -> Features<T> {
+ pub fn empty() -> Self {
Features {
flags: Vec::new(),
mark: PhantomData,
}
}
- #[cfg(test)]
- /// Create a Features given a set of flags, in LE.
+ /// Creates a Features with the bits set which are known by the implementation
+ pub fn known() -> Self {
+ Self {
+ flags: T::KNOWN_FEATURE_FLAGS.to_vec(),
+ mark: PhantomData,
+ }
+ }
+
+ /// Converts `Features<T>` to `Features<C>`. Only known `T` features relevant to context `C` are
+ /// included in the result.
+ fn to_context_internal<C: sealed::Context>(&self) -> Features<C> {
+ 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 < 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::<C> { flags, mark: PhantomData, }
+ }
+
+ /// 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<u8>) -> Features<T> {
Features {
flags,
}
pub(crate) fn requires_unknown_bits(&self) -> bool {
- // Generates a bitmask with all even bits set except for the given features. Bitwise
- // AND-ing it with a byte will select unknown required features.
- macro_rules! features_excluding {
- ($($feature: ident)|*) => {
- (0b01_01_01_01
- $(
- & !(<sealed::InitContext as sealed::$feature>::REQUIRED_MASK)
- )*
- )
- }
- }
-
- self.flags.iter().enumerate().any(|(idx, &byte)| {
- (match idx {
- 0 => (byte & features_excluding![DataLossProtect | InitialRoutingSync | UpfrontShutdownScript]),
- 1 => (byte & features_excluding![VariableLengthOnion | PaymentSecret]),
- 2 => (byte & features_excluding![BasicMPP]),
- _ => (byte & features_excluding![]),
- }) != 0
+ // 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();
+ self.flags.iter().enumerate().any(|(i, &byte)| {
+ let required_features = 0b01_01_01_01;
+ let unknown_features = if i < byte_count {
+ !T::KNOWN_FEATURE_MASK[i]
+ } else {
+ 0b11_11_11_11
+ };
+ (byte & (required_features & unknown_features)) != 0
})
}
pub(crate) fn supports_unknown_bits(&self) -> bool {
- // Generates a bitmask with all even and odd bits set except for the given features. Bitwise
- // AND-ing it with a byte will select unknown supported features.
- macro_rules! features_excluding {
- ($($feature: ident)|*) => {
- (0b11_11_11_11
- $(
- & !(<sealed::InitContext as sealed::$feature>::REQUIRED_MASK)
- & !(<sealed::InitContext as sealed::$feature>::OPTIONAL_MASK)
- )*
- )
- }
- }
-
- self.flags.iter().enumerate().any(|(idx, &byte)| {
- (match idx {
- 0 => (byte & features_excluding![DataLossProtect | InitialRoutingSync | UpfrontShutdownScript]),
- 1 => (byte & features_excluding![VariableLengthOnion | PaymentSecret]),
- 2 => (byte & features_excluding![BasicMPP]),
- _ => byte,
- }) != 0
+ // Bitwise AND-ing with all even and odd bits set except for known features will select
+ // both required and optional unknown features.
+ let byte_count = T::KNOWN_FEATURE_MASK.len();
+ self.flags.iter().enumerate().any(|(i, &byte)| {
+ let unknown_features = if i < byte_count {
+ !T::KNOWN_FEATURE_MASK[i]
+ } else {
+ 0b11_11_11_11
+ };
+ (byte & unknown_features) != 0
})
}
}
#[cfg(test)]
- pub(crate) fn set_require_unknown_bits(&mut self) {
- let newlen = cmp::max(3, self.flags.len());
- self.flags.resize(newlen, 0u8);
- self.flags[2] |= 0x40;
+ pub(crate) fn set_required_unknown_bits(&mut self) {
+ <sealed::TestingContext as sealed::UnknownFeature>::set_required_bit(&mut self.flags);
}
#[cfg(test)]
- pub(crate) fn clear_require_unknown_bits(&mut self) {
- let newlen = cmp::max(3, self.flags.len());
- self.flags.resize(newlen, 0u8);
- self.flags[2] &= !0x40;
- if self.flags.len() == 3 && self.flags[2] == 0 {
- self.flags.resize(2, 0u8);
- }
- if self.flags.len() == 2 && self.flags[1] == 0 {
- self.flags.resize(1, 0u8);
- }
+ pub(crate) fn set_optional_unknown_bits(&mut self) {
+ <sealed::TestingContext as sealed::UnknownFeature>::set_optional_bit(&mut self.flags);
+ }
+
+ #[cfg(test)]
+ pub(crate) fn clear_unknown_bits(&mut self) {
+ <sealed::TestingContext as sealed::UnknownFeature>::clear_bits(&mut self.flags);
}
}
impl<T: sealed::DataLossProtect> Features<T> {
+ #[cfg(test)]
+ pub(crate) fn requires_data_loss_protect(&self) -> bool {
+ <T as sealed::DataLossProtect>::requires_feature(&self.flags)
+ }
pub(crate) fn supports_data_loss_protect(&self) -> bool {
<T as sealed::DataLossProtect>::supports_feature(&self.flags)
}
}
impl<T: sealed::UpfrontShutdownScript> Features<T> {
+ #[cfg(test)]
+ pub(crate) fn requires_upfront_shutdown_script(&self) -> bool {
+ <T as sealed::UpfrontShutdownScript>::requires_feature(&self.flags)
+ }
pub(crate) fn supports_upfront_shutdown_script(&self) -> bool {
<T as sealed::UpfrontShutdownScript>::supports_feature(&self.flags)
}
#[cfg(test)]
- pub(crate) fn unset_upfront_shutdown_script(&mut self) {
- <T as sealed::UpfrontShutdownScript>::clear_optional_bit(&mut self.flags)
+ pub(crate) fn clear_upfront_shutdown_script(mut self) -> Self {
+ <T as sealed::UpfrontShutdownScript>::clear_bits(&mut self.flags);
+ self
+ }
+}
+
+
+impl<T: sealed::GossipQueries> Features<T> {
+ #[cfg(test)]
+ pub(crate) fn requires_gossip_queries(&self) -> bool {
+ <T as sealed::GossipQueries>::requires_feature(&self.flags)
+ }
+ pub(crate) fn supports_gossip_queries(&self) -> bool {
+ <T as sealed::GossipQueries>::supports_feature(&self.flags)
+ }
+ #[cfg(test)]
+ pub(crate) fn clear_gossip_queries(mut self) -> Self {
+ <T as sealed::GossipQueries>::clear_bits(&mut self.flags);
+ self
}
}
impl<T: sealed::VariableLengthOnion> Features<T> {
+ #[cfg(test)]
+ pub(crate) fn requires_variable_length_onion(&self) -> bool {
+ <T as sealed::VariableLengthOnion>::requires_feature(&self.flags)
+ }
pub(crate) fn supports_variable_length_onion(&self) -> bool {
<T as sealed::VariableLengthOnion>::supports_feature(&self.flags)
}
}
+impl<T: sealed::StaticRemoteKey> Features<T> {
+ pub(crate) fn supports_static_remote_key(&self) -> bool {
+ <T as sealed::StaticRemoteKey>::supports_feature(&self.flags)
+ }
+ #[cfg(test)]
+ pub(crate) fn requires_static_remote_key(&self) -> bool {
+ <T as sealed::StaticRemoteKey>::requires_feature(&self.flags)
+ }
+}
+
impl<T: sealed::InitialRoutingSync> Features<T> {
pub(crate) fn initial_routing_sync(&self) -> bool {
<T as sealed::InitialRoutingSync>::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.
+ #[cfg(test)]
pub(crate) fn clear_initial_routing_sync(&mut self) {
- <T as sealed::InitialRoutingSync>::clear_optional_bit(&mut self.flags)
+ <T as sealed::InitialRoutingSync>::clear_bits(&mut self.flags)
}
}
impl<T: sealed::PaymentSecret> Features<T> {
- #[allow(dead_code)]
- // 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).
- pub(crate) fn supports_payment_secret(&self) -> bool {
+ #[cfg(test)]
+ pub(crate) fn requires_payment_secret(&self) -> bool {
+ <T as sealed::PaymentSecret>::requires_feature(&self.flags)
+ }
+ /// Returns whether the `payment_secret` feature is supported.
+ pub fn supports_payment_secret(&self) -> bool {
<T as sealed::PaymentSecret>::supports_feature(&self.flags)
}
}
impl<T: sealed::BasicMPP> Features<T> {
+ #[cfg(test)]
+ pub(crate) fn requires_basic_mpp(&self) -> bool {
+ <T as sealed::BasicMPP>::requires_feature(&self.flags)
+ }
// We currently never test for this since we don't actually *generate* multipath routes.
- #[allow(dead_code)]
pub(crate) fn supports_basic_mpp(&self) -> bool {
<T as sealed::BasicMPP>::supports_feature(&self.flags)
}
}
+impl<T: sealed::ShutdownAnySegwit> Features<T> {
+ pub(crate) fn supports_shutdown_anysegwit(&self) -> bool {
+ <T as sealed::ShutdownAnySegwit>::supports_feature(&self.flags)
+ }
+ #[cfg(test)]
+ pub(crate) fn clear_shutdown_anysegwit(mut self) -> Self {
+ <T as sealed::ShutdownAnySegwit>::clear_bits(&mut self.flags);
+ self
+ }
+}
+
impl<T: sealed::Context> Writeable for Features<T> {
fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
w.size_hint(self.flags.len() + 2);
#[cfg(test)]
mod tests {
- use super::{ChannelFeatures, InitFeatures, NodeFeatures, Features};
+ use super::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
+ use bitcoin::bech32::{Base32Len, FromBase32, ToBase32, u5};
#[test]
- fn sanity_test_our_features() {
- assert!(!ChannelFeatures::supported().requires_unknown_bits());
- assert!(!ChannelFeatures::supported().supports_unknown_bits());
- assert!(!InitFeatures::supported().requires_unknown_bits());
- assert!(!InitFeatures::supported().supports_unknown_bits());
- assert!(!NodeFeatures::supported().requires_unknown_bits());
- assert!(!NodeFeatures::supported().supports_unknown_bits());
-
- assert!(InitFeatures::supported().supports_upfront_shutdown_script());
- assert!(NodeFeatures::supported().supports_upfront_shutdown_script());
-
- assert!(InitFeatures::supported().supports_data_loss_protect());
- assert!(NodeFeatures::supported().supports_data_loss_protect());
-
- assert!(InitFeatures::supported().supports_variable_length_onion());
- assert!(NodeFeatures::supported().supports_variable_length_onion());
-
- assert!(InitFeatures::supported().supports_payment_secret());
- assert!(NodeFeatures::supported().supports_payment_secret());
-
- assert!(InitFeatures::supported().supports_basic_mpp());
- assert!(NodeFeatures::supported().supports_basic_mpp());
-
- let mut init_features = InitFeatures::supported();
+ fn sanity_test_known_features() {
+ assert!(!ChannelFeatures::known().requires_unknown_bits());
+ assert!(!ChannelFeatures::known().supports_unknown_bits());
+ assert!(!InitFeatures::known().requires_unknown_bits());
+ assert!(!InitFeatures::known().supports_unknown_bits());
+ assert!(!NodeFeatures::known().requires_unknown_bits());
+ assert!(!NodeFeatures::known().supports_unknown_bits());
+
+ assert!(InitFeatures::known().supports_upfront_shutdown_script());
+ assert!(NodeFeatures::known().supports_upfront_shutdown_script());
+ assert!(!InitFeatures::known().requires_upfront_shutdown_script());
+ assert!(!NodeFeatures::known().requires_upfront_shutdown_script());
+
+ assert!(InitFeatures::known().supports_gossip_queries());
+ assert!(NodeFeatures::known().supports_gossip_queries());
+ assert!(!InitFeatures::known().requires_gossip_queries());
+ assert!(!NodeFeatures::known().requires_gossip_queries());
+
+ assert!(InitFeatures::known().supports_data_loss_protect());
+ assert!(NodeFeatures::known().supports_data_loss_protect());
+ assert!(!InitFeatures::known().requires_data_loss_protect());
+ assert!(!NodeFeatures::known().requires_data_loss_protect());
+
+ assert!(InitFeatures::known().supports_variable_length_onion());
+ assert!(NodeFeatures::known().supports_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());
+ assert!(InitFeatures::known().requires_static_remote_key());
+ assert!(NodeFeatures::known().requires_static_remote_key());
+
+ assert!(InitFeatures::known().supports_payment_secret());
+ assert!(NodeFeatures::known().supports_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());
+
+ let mut init_features = InitFeatures::known();
assert!(init_features.initial_routing_sync());
init_features.clear_initial_routing_sync();
assert!(!init_features.initial_routing_sync());
}
#[test]
- fn sanity_test_unkown_bits_testing() {
- let mut features = ChannelFeatures::supported();
- features.set_require_unknown_bits();
+ fn sanity_test_unknown_bits() {
+ let mut features = ChannelFeatures::empty();
+ assert!(!features.requires_unknown_bits());
+ assert!(!features.supports_unknown_bits());
+
+ features.set_required_unknown_bits();
assert!(features.requires_unknown_bits());
- features.clear_require_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();
+ assert!(!features.requires_unknown_bits());
+ assert!(features.supports_unknown_bits());
}
#[test]
- fn test_node_with_known_relevant_init_flags() {
- // Create an InitFeatures with initial_routing_sync supported.
- let init_features = InitFeatures::supported();
+ fn convert_to_context_with_relevant_flags() {
+ let init_features = InitFeatures::known().clear_upfront_shutdown_script().clear_gossip_queries();
assert!(init_features.initial_routing_sync());
+ assert!(!init_features.supports_upfront_shutdown_script());
+ assert!(!init_features.supports_gossip_queries());
- // Attempt to pull out non-node-context feature flags from these InitFeatures.
- let res = NodeFeatures::with_known_relevant_init_flags(&init_features);
-
+ let node_features: NodeFeatures = init_features.to_context();
{
- // Check that the flags are as expected: optional_data_loss_protect,
- // option_upfront_shutdown_script, var_onion_optin, payment_secret, and
- // basic_mpp.
- assert_eq!(res.flags.len(), 3);
- assert_eq!(res.flags[0], 0b00100010);
- assert_eq!(res.flags[1], 0b10000010);
- assert_eq!(res.flags[2], 0b00000010);
+ // Check that the flags are as expected:
+ // - option_data_loss_protect
+ // - 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], 0b01010001);
+ assert_eq!(node_features.flags[2], 0b00000010);
+ assert_eq!(node_features.flags[3], 0b00001000);
}
- // Check that the initial_routing_sync feature was correctly blanked out.
- let new_features: InitFeatures = Features::from_le_bytes(res.flags);
- assert!(!new_features.initial_routing_sync());
+ // Check that cleared flags are kept blank when converting back:
+ // - initial_routing_sync was not applicable to NodeContext
+ // - upfront_shutdown_script was cleared before converting
+ // - gossip_queries was cleared before converting
+ let features: InitFeatures = node_features.to_context_internal();
+ assert!(!features.initial_routing_sync());
+ assert!(!features.supports_upfront_shutdown_script());
+ assert!(!init_features.supports_gossip_queries());
+ }
+
+ #[test]
+ fn set_feature_bits() {
+ let features = InvoiceFeatures::empty()
+ .set_basic_mpp_optional()
+ .set_payment_secret_required();
+ assert!(features.supports_basic_mpp());
+ assert!(!features.requires_basic_mpp());
+ 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);
}
}
projects / rust-lightning / blobdiff