Merge pull request #2722 from benthecarman/dust-overflow

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

diff --git a/lightning/src/ln/onion_utils.rs b/lightning/src/ln/onion_utils.rs
index 390826e4f3d2938b32a69855b8b70eab2d476e3e..e952bd8e2e125c5d8c16ef6f8419e1c8a2579ba0 100644 (file)
--- a/lightning/src/ln/onion_utils.rs
+++ b/lightning/src/ln/onion_utils.rs
@@ -93,7 +93,7 @@ pub(super) fn gen_pad_from_shared_secret(shared_secret: &[u8]) -> [u8; 32] {
 }
 
 /// Calculates a pubkey for the next hop, such as the next hop's packet pubkey or blinding point.
-pub(crate) fn next_hop_pubkey<T: secp256k1::Signing + secp256k1::Verification>(
+pub(crate) fn next_hop_pubkey<T: secp256k1::Verification>(
        secp_ctx: &Secp256k1<T>, curr_pubkey: PublicKey, shared_secret: &[u8]
 ) -> Result<PublicKey, secp256k1::Error> {
        let blinding_factor = {
@@ -935,6 +935,27 @@ pub(crate) fn decode_next_payment_hop<NS: Deref>(
        }
 }
 
+/// Build a payment onion, returning the first hop msat and cltv values as well.
+/// `cur_block_height` should be set to the best known block height + 1.
+pub fn create_payment_onion<T: secp256k1::Signing>(
+       secp_ctx: &Secp256k1<T>, path: &Path, session_priv: &SecretKey, total_msat: u64,
+       recipient_onion: RecipientOnionFields, cur_block_height: u32, payment_hash: &PaymentHash,
+       keysend_preimage: &Option<PaymentPreimage>, prng_seed: [u8; 32]
+) -> Result<(msgs::OnionPacket, u64, u32), APIError> {
+       let onion_keys = construct_onion_keys(&secp_ctx, &path, &session_priv)
+               .map_err(|_| APIError::InvalidRoute{
+                       err: "Pubkey along hop was maliciously selected".to_owned()
+               })?;
+       let (onion_payloads, htlc_msat, htlc_cltv) = build_onion_payloads(
+               &path, total_msat, recipient_onion, cur_block_height, keysend_preimage
+       )?;
+       let onion_packet = construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash)
+               .map_err(|_| APIError::InvalidRoute{
+                       err: "Route size too large considering onion data".to_owned()
+               })?;
+       Ok((onion_packet, htlc_msat, htlc_cltv))
+}
+
 pub(crate) fn decode_next_untagged_hop<T, R: ReadableArgs<T>, N: NextPacketBytes>(shared_secret: [u8; 32], hop_data: &[u8], hmac_bytes: [u8; 32], read_args: T) -> Result<(R, Option<([u8; 32], N)>), OnionDecodeErr> {
        decode_next_hop(shared_secret, hop_data, hmac_bytes, None, read_args)
 }
@@ -1046,27 +1067,27 @@ mod tests {
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
                                                channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // We fill in the payloads manually instead of generating them from RouteHops.
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0, maybe_announced_channel: true, // We fill in the payloads manually instead of generating them from RouteHops.
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
                                                channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // We fill in the payloads manually instead of generating them from RouteHops.
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0, maybe_announced_channel: true, // We fill in the payloads manually instead of generating them from RouteHops.
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
                                                channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // We fill in the payloads manually instead of generating them from RouteHops.
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0, maybe_announced_channel: true, // We fill in the payloads manually instead of generating them from RouteHops.
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]).unwrap(),
                                                channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // We fill in the payloads manually instead of generating them from RouteHops.
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0, maybe_announced_channel: true, // We fill in the payloads manually instead of generating them from RouteHops.
                                        },
                                        RouteHop {
                                                pubkey: PublicKey::from_slice(&hex::decode("02edabbd16b41c8371b92ef2f04c1185b4f03b6dcd52ba9b78d9d7c89c8f221145").unwrap()[..]).unwrap(),
                                                channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // We fill in the payloads manually instead of generating them from RouteHops.
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0, maybe_announced_channel: true, // We fill in the payloads manually instead of generating them from RouteHops.
                                        },
                        ], blinded_tail: None }],
                        route_params: None,