//! 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
//! 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 {io, io_extras};
+use prelude::*;
+use core::{cmp, fmt};
+use core::hash::{Hash, Hasher};
+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
/// which are optional for the context.
- ///
- /// [`Features`]: ../struct.Features.html
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.
/// 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.
- ///
- /// [`Context`]: trait.Context.html
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 $context {
)*
];
}
+
+ impl alloc::fmt::Display for Features<$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" }))
+ }
+ }
};
}
// Byte 0
,
// Byte 1
- StaticRemoteKey,
+ VariableLengthOnion | StaticRemoteKey | PaymentSecret,
// Byte 2
,
+ // Byte 3
+ ,
+ // Byte 4
+ ,
+ // Byte 5
+ ,
],
optional_features: [
// Byte 0
DataLossProtect | InitialRoutingSync | UpfrontShutdownScript | GossipQueries,
// Byte 1
- VariableLengthOnion | PaymentSecret,
+ ,
// Byte 2
BasicMPP,
+ // Byte 3
+ ShutdownAnySegwit,
+ // Byte 4
+ ,
+ // Byte 5
+ ChannelType,
],
});
define_context!(NodeContext {
// Byte 0
,
// Byte 1
- StaticRemoteKey,
+ VariableLengthOnion | StaticRemoteKey | PaymentSecret,
// Byte 2
,
+ // Byte 3
+ ,
+ // Byte 4
+ ,
+ // Byte 5
+ ,
+ // Byte 6
+ ,
],
optional_features: [
// Byte 0
DataLossProtect | UpfrontShutdownScript | GossipQueries,
// Byte 1
- VariableLengthOnion | PaymentSecret,
+ ,
// Byte 2
BasicMPP,
+ // Byte 3
+ ShutdownAnySegwit,
+ // Byte 4
+ ,
+ // Byte 5
+ ChannelType,
+ // Byte 6
+ Keysend,
],
});
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,
+ ],
+ });
+ // 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
+ ,
+ ],
+ optional_features: [
+ // Byte 0
+ ,
+ // Byte 1
+ ,
+ // Byte 2
+ ,
+ // Byte 3
+ ,
+ ],
+ });
/// 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, $supported_getter: ident) => {
#[doc = $doc]
///
/// See [BOLT #9] for details.
}
}
+ 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
+ }
+
+ /// Checks if this feature is supported.
+ pub fn $supported_getter(&self) -> bool {
+ <T as $feature>::supports_feature(&self.flags)
+ }
+ }
+
$(
impl $feature for $context {
// EVEN_BIT % 2 == 0
const ASSERT_ODD_BIT_PARITY: usize = (<Self as $feature>::ODD_BIT % 2) - 1;
}
)*
+ };
+ ($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 <T: $feature> Features<T> {
+ /// Checks if this feature is required.
+ pub fn $required_getter(&self) -> bool {
+ <T as $feature>::requires_feature(&self.flags)
+ }
+ }
}
}
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, 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`.");
+ define_feature!(3, InitialRoutingSync, [InitContext], "Feature flags for `initial_routing_sync`.",
+ 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`.");
+ "Feature flags for `option_upfront_shutdown_script`.", set_upfront_shutdown_script_optional,
+ set_upfront_shutdown_script_required, supports_upfront_shutdown_script,
+ requires_upfront_shutdown_script);
define_feature!(7, GossipQueries, [InitContext, NodeContext],
- "Feature flags for `gossip_queries`.");
- define_feature!(9, VariableLengthOnion, [InitContext, NodeContext],
- "Feature flags for `var_onion_optin`.");
- define_feature!(13, StaticRemoteKey, [InitContext, NodeContext],
- "Feature flags for `option_static_remotekey`.");
- define_feature!(15, PaymentSecret, [InitContext, NodeContext],
- "Feature flags for `payment_secret`.");
- define_feature!(17, BasicMPP, [InitContext, NodeContext],
- "Feature flags for `basic_mpp`.");
-
- #[cfg(test)]
- define_context!(TestingContext {
- required_features: [
- // Byte 0
- ,
- // Byte 1
- ,
- // Byte 2
- UnknownFeature,
- ],
- optional_features: [
- // Byte 0
- ,
- // Byte 1
- ,
- // Byte 2
- ,
- ],
- });
+ "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, 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, 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,
+ 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,
+ supports_basic_mpp, requires_basic_mpp);
+ 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!(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!(55, Keysend, [NodeContext],
+ "Feature flags for keysend payments.", set_keysend_optional, set_keysend_required,
+ supports_keysend, requires_keysend);
#[cfg(test)]
- define_feature!(23, UnknownFeature, [TestingContext],
- "Feature flags for an unknown feature used in testing.");
+ define_feature!(123456789, UnknownFeature, [NodeContext, ChannelContext, InvoiceContext],
+ "Feature flags for an unknown feature used in testing.", set_unknown_feature_optional,
+ 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
/// 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>,
}
}
}
+impl<T: sealed::Context> Hash for Features<T> {
+ fn hash<H: Hasher>(&self, hasher: &mut H) {
+ self.flags.hash(hasher);
+ }
+}
impl<T: sealed::Context> PartialEq for Features<T> {
fn eq(&self, o: &Self) -> bool {
self.flags.eq(&o.flags)
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>;
+
+/// 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<sealed::ChannelTypeContext>;
impl InitFeatures {
/// 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> {
+ pub(crate) fn write_up_to_13<W: Writer>(&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 {
}
}
+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()
+ }
+
+ /// 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
+ /// [`PaymentParameters::for_keysend`], thus omitting the need for payers to manually construct an
+ /// `InvoiceFeatures` for [`find_route`].
+ ///
+ /// [`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()
+ }
+}
+
+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();
+ <sealed::ChannelTypeContext as sealed::StaticRemoteKey>::set_required_bit(&mut ret.flags);
+ ret
+ }
+}
+
+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();
+ }
+ }
+ // 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<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;
+ }
+ }
+ // 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,
}
}
- /// Creates features known by the implementation as defined by [`T::KNOWN_FEATURE_FLAGS`].
- ///
- /// [`T::KNOWN_FEATURE_FLAGS`]: sealed/trait.Context.html#associatedconstant.KNOWN_FEATURE_FLAGS
- pub fn known() -> Features<T> {
+ /// 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 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::<C> { 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<u8>) -> Features<T> {
Features {
flags,
&self.flags
}
- pub(crate) fn requires_unknown_bits(&self) -> bool {
+ fn write_be<W: Writer>(&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<u8>) -> Features<T> {
+ 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 {
// 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();
(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()
- }
-
- #[cfg(test)]
- 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 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 clear_upfront_shutdown_script(mut self) -> Self {
<T as sealed::UpfrontShutdownScript>::clear_bits(&mut self.flags);
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)
- }
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_bits(&mut self.flags)
}
}
-impl<T: sealed::PaymentSecret> Features<T> {
+impl<T: sealed::ShutdownAnySegwit> Features<T> {
#[cfg(test)]
- pub(crate) fn requires_payment_secret(&self) -> bool {
- <T as sealed::PaymentSecret>::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 {
- <T as sealed::PaymentSecret>::supports_feature(&self.flags)
+ pub(crate) fn clear_shutdown_anysegwit(mut self) -> Self {
+ <T as sealed::ShutdownAnySegwit>::clear_bits(&mut self.flags);
+ self
}
}
-
-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)
+macro_rules! impl_feature_len_prefixed_write {
+ ($features: ident) => {
+ impl Writeable for $features {
+ fn write<W: Writer>(&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: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
+ Ok(Self::from_be_bytes(Vec::<u8>::read(r)?))
+ }
+ }
}
}
-
-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);
- (self.flags.len() as u16).write(w)?;
- for f in self.flags.iter().rev() { // Swap back to big-endian
- f.write(w)?;
- }
- Ok(())
+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<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+ self.write_be(w)
}
}
-
-impl<T: sealed::Context> Readable for Features<T> {
- fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
- let mut flags: Vec<u8> = Readable::read(r)?;
- flags.reverse(); // Swap to little-endian
- Ok(Self {
- flags,
- mark: PhantomData,
- })
+impl Readable for ChannelTypeFeatures {
+ fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let v = io_extras::read_to_end(r)?;
+ Ok(Self::from_be_bytes(v))
}
}
#[cfg(test)]
mod tests {
- use super::{ChannelFeatures, InitFeatures, NodeFeatures};
+ use super::{ChannelFeatures, ChannelTypeFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
+ use bitcoin::bech32::{Base32Len, FromBase32, ToBase32, u5};
#[test]
fn sanity_test_known_features() {
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());
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_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());
let mut init_features = InitFeatures::known();
assert!(init_features.initial_routing_sync());
#[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());
}
{
// 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
- assert_eq!(node_features.flags.len(), 3);
+ // - opt_shutdown_anysegwit
+ // -
+ // - option_channel_type
+ assert_eq!(node_features.flags.len(), 6);
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);
+ assert_eq!(node_features.flags[4], 0b00000000);
+ assert_eq!(node_features.flags[5], 0b00100000);
}
// Check that cleared flags are kept blank when converting back:
assert!(!features.supports_upfront_shutdown_script());
assert!(!init_features.supports_gossip_queries());
}
+
+ #[test]
+ 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();
+ assert!(invoice_features.supports_unknown_bits());
+ let node_features: NodeFeatures = invoice_features.to_context();
+ assert!(!node_features.supports_unknown_bits());
+ }
+
+ #[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);
+ }
+
+ #[test]
+ fn test_channel_type_mapping() {
+ // If we map an InvoiceFeatures with StaticRemoteKey optional, it should map into a
+ // required-StaticRemoteKey ChannelTypeFeatures.
+ let init_features = InitFeatures::empty().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());
+ }
}