Create new `InvoiceFeatures` object for Invoice-specific features
[rust-lightning] / lightning / src / ln / features.rs
index ad8942326322f75207e42d0a9ec3f09ee86fc0a7..efed0b10ed2ae72935f9742b1f4594ed0e90100b 100644 (file)
@@ -1,3 +1,12 @@
+// 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
@@ -17,7 +26,6 @@
 //! [`Context`]: sealed/trait.Context.html
 
 use std::{cmp, fmt};
-use std::result::Result;
 use std::marker::PhantomData;
 
 use ln::msgs::DecodeError;
@@ -89,17 +97,21 @@ mod sealed {
                        // Byte 0
                        ,
                        // Byte 1
-                       ,
+                       StaticRemoteKey,
                        // Byte 2
                        ,
+                       // Byte 3
+                       ,
                ],
                optional_features: [
                        // Byte 0
-                       DataLossProtect | InitialRoutingSync | UpfrontShutdownScript,
+                       DataLossProtect | InitialRoutingSync | UpfrontShutdownScript | GossipQueries,
                        // Byte 1
                        VariableLengthOnion | PaymentSecret,
                        // Byte 2
                        BasicMPP,
+                       // Byte 3
+                       ShutdownAnySegwit,
                ],
        });
        define_context!(NodeContext {
@@ -107,23 +119,38 @@ mod sealed {
                        // Byte 0
                        ,
                        // Byte 1
-                       ,
+                       StaticRemoteKey,
                        // Byte 2
                        ,
+                       // Byte 3
+                       ,
                ],
                optional_features: [
                        // Byte 0
-                       DataLossProtect | UpfrontShutdownScript,
+                       DataLossProtect | UpfrontShutdownScript | GossipQueries,
                        // Byte 1
                        VariableLengthOnion | PaymentSecret,
                        // Byte 2
                        BasicMPP,
+                       // Byte 3
+                       ShutdownAnySegwit,
                ],
        });
        define_context!(ChannelContext {
                required_features: [],
                optional_features: [],
        });
+       define_context!(InvoiceContext {
+               required_features: [,,,],
+               optional_features: [
+                       // Byte 0
+                       ,
+                       // Byte 1
+                       VariableLengthOnion | PaymentSecret,
+                       // Byte 2
+                       BasicMPP,
+               ],
+       });
 
        /// Defines a feature with the given bits for the specified [`Context`]s. The generated trait is
        /// useful for manipulating feature flags.
@@ -234,14 +261,18 @@ mod sealed {
                "Feature flags for `initial_routing_sync`.");
        define_feature!(5, UpfrontShutdownScript, [InitContext, NodeContext],
                "Feature flags for `option_upfront_shutdown_script`.");
-       define_feature!(9, VariableLengthOnion, [InitContext, NodeContext],
+       define_feature!(7, GossipQueries, [InitContext, NodeContext],
+               "Feature flags for `gossip_queries`.");
+       define_feature!(9, VariableLengthOnion, [InitContext, NodeContext, InvoiceContext],
                "Feature flags for `var_onion_optin`.");
        define_feature!(13, StaticRemoteKey, [InitContext, NodeContext],
                "Feature flags for `option_static_remotekey`.");
-       define_feature!(15, PaymentSecret, [InitContext, NodeContext],
+       define_feature!(15, PaymentSecret, [InitContext, NodeContext, InvoiceContext],
                "Feature flags for `payment_secret`.");
-       define_feature!(17, BasicMPP, [InitContext, NodeContext],
+       define_feature!(17, BasicMPP, [InitContext, NodeContext, InvoiceContext],
                "Feature flags for `basic_mpp`.");
+       define_feature!(27, ShutdownAnySegwit, [InitContext, NodeContext],
+               "Feature flags for `opt_shutdown_anysegwit`.");
 
        #[cfg(test)]
        define_context!(TestingContext {
@@ -270,6 +301,8 @@ mod sealed {
 
 /// 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
 pub struct Features<T: sealed::Context> {
        /// Note that, for convenience, flags is LITTLE endian (despite being big-endian on the wire)
        flags: Vec<u8>,
@@ -301,6 +334,8 @@ pub type InitFeatures = Features<sealed::InitContext>;
 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 {
        /// Writes all features present up to, and including, 13.
@@ -337,9 +372,17 @@ impl InitFeatures {
        }
 }
 
+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<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,
@@ -349,7 +392,7 @@ impl<T: sealed::Context> Features<T> {
        /// 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> {
+       pub fn known() -> Self {
                Self {
                        flags: T::KNOWN_FEATURE_FLAGS.to_vec(),
                        mark: PhantomData,
@@ -462,6 +505,22 @@ impl<T: sealed::UpfrontShutdownScript> Features<T> {
        }
 }
 
+
+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 {
@@ -486,6 +545,10 @@ 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)
        }
@@ -517,6 +580,17 @@ impl<T: sealed::BasicMPP> Features<T> {
        }
 }
 
+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);
@@ -557,6 +631,11 @@ mod tests {
                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());
@@ -567,10 +646,10 @@ mod tests {
                assert!(!InitFeatures::known().requires_variable_length_onion());
                assert!(!NodeFeatures::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_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());
@@ -582,6 +661,9 @@ mod tests {
                assert!(!InitFeatures::known().requires_basic_mpp());
                assert!(!NodeFeatures::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();
@@ -609,27 +691,32 @@ mod tests {
 
        #[test]
        fn convert_to_context_with_relevant_flags() {
-               let init_features = InitFeatures::known().clear_upfront_shutdown_script();
+               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());
 
                let node_features: NodeFeatures = init_features.to_context();
                {
                        // Check that the flags are as expected:
                        // - option_data_loss_protect
-                       // - var_onion_optin | payment_secret
+                       // - var_onion_optin | static_remote_key (req) | payment_secret
                        // - basic_mpp
-                       assert_eq!(node_features.flags.len(), 3);
+                       // - opt_shutdown_anysegwit
+                       assert_eq!(node_features.flags.len(), 4);
                        assert_eq!(node_features.flags[0], 0b00000010);
-                       assert_eq!(node_features.flags[1], 0b10000010);
+                       assert_eq!(node_features.flags[1], 0b10010010);
                        assert_eq!(node_features.flags[2], 0b00000010);
+                       assert_eq!(node_features.flags[3], 0b00001000);
                }
 
                // 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());
        }
 }