Merge pull request #2400 from TheBlueMatt/2023-07-kill-vec_type

[rust-lightning] / lightning / src / ln / features.rs

diff --git a/lightning/src/ln/features.rs b/lightning/src/ln/features.rs
index b8087546c7445060230a5ad776a9b3f13c113d37..ca6ea70b61da7312de22b1e28749a51cb3f28941 100644 (file)
--- a/lightning/src/ln/features.rs
+++ b/lightning/src/ln/features.rs
@@ -65,12 +65,19 @@
 //!     [BOLT-3](https://github.com/lightning/bolts/blob/master/03-transactions.md) for more
 //!     information).
 //!
+//! LDK knows about the following features, but does not support them:
+//! - `AnchorsNonzeroFeeHtlcTx` - the initial version of anchor outputs, which was later found to be
+//!     vulnerable (see this
+//!     [mailing list post](https://lists.linuxfoundation.org/pipermail/lightning-dev/2020-September/002796.html)
+//!     for more information).
+//!
 //! [BOLT #9]: https://github.com/lightning/bolts/blob/master/09-features.md
 //! [messages]: crate::ln::msgs
 
 use crate::{io, io_extras};
 use crate::prelude::*;
 use core::{cmp, fmt};
+use core::borrow::Borrow;
 use core::hash::{Hash, Hasher};
 use core::marker::PhantomData;
 
@@ -134,7 +141,7 @@ mod sealed {
                // Byte 1
                VariableLengthOnion | StaticRemoteKey | PaymentSecret,
                // Byte 2
-               BasicMPP | Wumbo | AnchorsZeroFeeHtlcTx,
+               BasicMPP | Wumbo | AnchorsNonzeroFeeHtlcTx | AnchorsZeroFeeHtlcTx,
                // Byte 3
                ShutdownAnySegwit,
                // Byte 4
@@ -150,7 +157,7 @@ mod sealed {
                // Byte 1
                VariableLengthOnion | StaticRemoteKey | PaymentSecret,
                // Byte 2
-               BasicMPP | Wumbo | AnchorsZeroFeeHtlcTx,
+               BasicMPP | Wumbo | AnchorsNonzeroFeeHtlcTx | AnchorsZeroFeeHtlcTx,
                // Byte 3
                ShutdownAnySegwit,
                // Byte 4
@@ -196,7 +203,7 @@ mod sealed {
                // Byte 1
                StaticRemoteKey,
                // Byte 2
-               AnchorsZeroFeeHtlcTx,
+               AnchorsNonzeroFeeHtlcTx | AnchorsZeroFeeHtlcTx,
                // Byte 3
                ,
                // Byte 4
@@ -378,6 +385,9 @@ mod sealed {
        define_feature!(19, Wumbo, [InitContext, NodeContext],
                "Feature flags for `option_support_large_channel` (aka wumbo channels).", set_wumbo_optional, set_wumbo_required,
                supports_wumbo, requires_wumbo);
+       define_feature!(21, AnchorsNonzeroFeeHtlcTx, [InitContext, NodeContext, ChannelTypeContext],
+               "Feature flags for `option_anchors_nonzero_fee_htlc_tx`.", set_anchors_nonzero_fee_htlc_tx_optional,
+               set_anchors_nonzero_fee_htlc_tx_required, supports_anchors_nonzero_fee_htlc_tx, requires_anchors_nonzero_fee_htlc_tx);
        define_feature!(23, AnchorsZeroFeeHtlcTx, [InitContext, NodeContext, ChannelTypeContext],
                "Feature flags for `option_anchors_zero_fee_htlc_tx`.", set_anchors_zero_fee_htlc_tx_optional,
                set_anchors_zero_fee_htlc_tx_required, supports_anchors_zero_fee_htlc_tx, requires_anchors_zero_fee_htlc_tx);
@@ -422,15 +432,21 @@ pub struct Features<T: sealed::Context> {
        mark: PhantomData<T>,
 }
 
+impl<T: sealed::Context, Rhs: Borrow<Self>> core::ops::BitOrAssign<Rhs> for Features<T> {
+       fn bitor_assign(&mut self, rhs: Rhs) {
+               let total_feature_len = cmp::max(self.flags.len(), rhs.borrow().flags.len());
+               self.flags.resize(total_feature_len, 0u8);
+               for (byte, rhs_byte) in self.flags.iter_mut().zip(rhs.borrow().flags.iter()) {
+                       *byte |= *rhs_byte;
+               }
+       }
+}
+
 impl<T: sealed::Context> core::ops::BitOr for Features<T> {
        type Output = Self;
 
        fn bitor(mut self, o: Self) -> Self {
-               let total_feature_len = cmp::max(self.flags.len(), o.flags.len());
-               self.flags.resize(total_feature_len, 0u8);
-               for (byte, o_byte) in self.flags.iter_mut().zip(o.flags.iter()) {
-                       *byte |= *o_byte;
-               }
+               self |= o;
                self
        }
 }
@@ -535,11 +551,17 @@ impl InvoiceFeatures {
        /// [`PaymentParameters::for_keysend`], thus omitting the need for payers to manually construct an
        /// `InvoiceFeatures` for [`find_route`].
        ///
+       /// MPP keysend is not widely supported yet, so we parameterize support to allow the user to
+       /// choose whether their router should find multi-part routes.
+       ///
        /// [`PaymentParameters::for_keysend`]: crate::routing::router::PaymentParameters::for_keysend
        /// [`find_route`]: crate::routing::router::find_route
-       pub(crate) fn for_keysend() -> InvoiceFeatures {
+       pub(crate) fn for_keysend(allow_mpp: bool) -> InvoiceFeatures {
                let mut res = InvoiceFeatures::empty();
                res.set_variable_length_onion_optional();
+               if allow_mpp {
+                       res.set_basic_mpp_optional();
+               }
                res
        }
 }
@@ -572,6 +594,14 @@ impl ChannelTypeFeatures {
                <sealed::ChannelTypeContext as sealed::StaticRemoteKey>::set_required_bit(&mut ret.flags);
                ret
        }
+
+       /// Constructs a ChannelTypeFeatures with anchors support
+       pub(crate) fn anchors_zero_htlc_fee_and_dependencies() -> Self {
+               let mut ret = Self::empty();
+               <sealed::ChannelTypeContext as sealed::StaticRemoteKey>::set_required_bit(&mut ret.flags);
+               <sealed::ChannelTypeContext as sealed::AnchorsZeroFeeHtlcTx>::set_required_bit(&mut ret.flags);
+               ret
+       }
 }
 
 impl ToBase32 for InvoiceFeatures {