Move onion encryption/decryption/etc into an onion_utils module
authorMatt Corallo <git@bluematt.me>
Wed, 19 Dec 2018 22:02:27 +0000 (17:02 -0500)
committerMatt Corallo <git@bluematt.me>
Thu, 20 Dec 2018 01:36:34 +0000 (20:36 -0500)
src/ln/channelmanager.rs
src/ln/mod.rs
src/ln/onion_utils.rs [new file with mode: 0644]

index 632ae9f037ea6c88451f202029987d5dde723748..4d52e00ea731bfd88cfda5a416e126cc8fb3fa89 100644 (file)
@@ -28,19 +28,20 @@ use chain::chaininterface::{BroadcasterInterface,ChainListener,ChainWatchInterfa
 use chain::transaction::OutPoint;
 use ln::channel::{Channel, ChannelError};
 use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, ManyChannelMonitor, CLTV_CLAIM_BUFFER, HTLC_FAIL_TIMEOUT_BLOCKS, HTLC_FAIL_ANTI_REORG_DELAY};
-use ln::router::{Route,RouteHop};
+use ln::router::Route;
 use ln::msgs;
+use ln::onion_utils;
 use ln::msgs::{ChannelMessageHandler, DecodeError, HandleError};
 use chain::keysinterface::KeysInterface;
 use util::config::UserConfig;
-use util::{byte_utils, events, internal_traits, rng};
+use util::{byte_utils, events, rng};
 use util::ser::{Readable, ReadableArgs, Writeable, Writer};
 use util::chacha20::ChaCha20;
 use util::logger::Logger;
 use util::errors::APIError;
 use util::errors;
 
-use std::{cmp, ptr, mem};
+use std::{cmp, mem};
 use std::collections::{HashMap, hash_map, HashSet};
 use std::io::Cursor;
 use std::sync::{Arc, Mutex, MutexGuard, RwLock};
@@ -349,16 +350,6 @@ macro_rules! secp_call {
        };
 }
 
-struct OnionKeys {
-       #[cfg(test)]
-       shared_secret: SharedSecret,
-       #[cfg(test)]
-       blinding_factor: [u8; 32],
-       ephemeral_pubkey: PublicKey,
-       rho: [u8; 32],
-       mu: [u8; 32],
-}
-
 /// Details of a channel, as returned by ChannelManager::list_channels and ChannelManager::list_usable_channels
 pub struct ChannelDetails {
        /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
@@ -708,240 +699,7 @@ impl ChannelManager {
                }
        }
 
-       #[inline]
-       fn gen_rho_mu_from_shared_secret(shared_secret: &[u8]) -> ([u8; 32], [u8; 32]) {
-               assert_eq!(shared_secret.len(), 32);
-               ({
-                       let mut hmac = HmacEngine::<Sha256>::new(&[0x72, 0x68, 0x6f]); // rho
-                       hmac.input(&shared_secret[..]);
-                       Hmac::from_engine(hmac).into_inner()
-               },
-               {
-                       let mut hmac = HmacEngine::<Sha256>::new(&[0x6d, 0x75]); // mu
-                       hmac.input(&shared_secret[..]);
-                       Hmac::from_engine(hmac).into_inner()
-               })
-       }
-
-       #[inline]
-       fn gen_um_from_shared_secret(shared_secret: &[u8]) -> [u8; 32] {
-               assert_eq!(shared_secret.len(), 32);
-               let mut hmac = HmacEngine::<Sha256>::new(&[0x75, 0x6d]); // um
-               hmac.input(&shared_secret[..]);
-               Hmac::from_engine(hmac).into_inner()
-       }
-
-       #[inline]
-       fn gen_ammag_from_shared_secret(shared_secret: &[u8]) -> [u8; 32] {
-               assert_eq!(shared_secret.len(), 32);
-               let mut hmac = HmacEngine::<Sha256>::new(&[0x61, 0x6d, 0x6d, 0x61, 0x67]); // ammag
-               hmac.input(&shared_secret[..]);
-               Hmac::from_engine(hmac).into_inner()
-       }
-
-       // can only fail if an intermediary hop has an invalid public key or session_priv is invalid
-       #[inline]
-       fn construct_onion_keys_callback<T: secp256k1::Signing, FType: FnMut(SharedSecret, [u8; 32], PublicKey, &RouteHop)> (secp_ctx: &Secp256k1<T>, route: &Route, session_priv: &SecretKey, mut callback: FType) -> Result<(), secp256k1::Error> {
-               let mut blinded_priv = session_priv.clone();
-               let mut blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
-
-               for hop in route.hops.iter() {
-                       let shared_secret = SharedSecret::new(secp_ctx, &hop.pubkey, &blinded_priv);
-
-                       let mut sha = Sha256::engine();
-                       sha.input(&blinded_pub.serialize()[..]);
-                       sha.input(&shared_secret[..]);
-                       let blinding_factor = Sha256::from_engine(sha).into_inner();
-
-                       let ephemeral_pubkey = blinded_pub;
-
-                       blinded_priv.mul_assign(secp_ctx, &SecretKey::from_slice(secp_ctx, &blinding_factor)?)?;
-                       blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
-
-                       callback(shared_secret, blinding_factor, ephemeral_pubkey, hop);
-               }
-
-               Ok(())
-       }
-
-       // can only fail if an intermediary hop has an invalid public key or session_priv is invalid
-       fn construct_onion_keys<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, route: &Route, session_priv: &SecretKey) -> Result<Vec<OnionKeys>, secp256k1::Error> {
-               let mut res = Vec::with_capacity(route.hops.len());
-
-               Self::construct_onion_keys_callback(secp_ctx, route, session_priv, |shared_secret, _blinding_factor, ephemeral_pubkey, _| {
-                       let (rho, mu) = ChannelManager::gen_rho_mu_from_shared_secret(&shared_secret[..]);
-
-                       res.push(OnionKeys {
-                               #[cfg(test)]
-                               shared_secret,
-                               #[cfg(test)]
-                               blinding_factor: _blinding_factor,
-                               ephemeral_pubkey,
-                               rho,
-                               mu,
-                       });
-               })?;
-
-               Ok(res)
-       }
-
-       /// returns the hop data, as well as the first-hop value_msat and CLTV value we should send.
-       fn build_onion_payloads(route: &Route, starting_htlc_offset: u32) -> Result<(Vec<msgs::OnionHopData>, u64, u32), APIError> {
-               let mut cur_value_msat = 0u64;
-               let mut cur_cltv = starting_htlc_offset;
-               let mut last_short_channel_id = 0;
-               let mut res: Vec<msgs::OnionHopData> = Vec::with_capacity(route.hops.len());
-               internal_traits::test_no_dealloc::<msgs::OnionHopData>(None);
-               unsafe { res.set_len(route.hops.len()); }
-
-               for (idx, hop) in route.hops.iter().enumerate().rev() {
-                       // First hop gets special values so that it can check, on receipt, that everything is
-                       // exactly as it should be (and the next hop isn't trying to probe to find out if we're
-                       // the intended recipient).
-                       let value_msat = if cur_value_msat == 0 { hop.fee_msat } else { cur_value_msat };
-                       let cltv = if cur_cltv == starting_htlc_offset { hop.cltv_expiry_delta + starting_htlc_offset } else { cur_cltv };
-                       res[idx] = msgs::OnionHopData {
-                               realm: 0,
-                               data: msgs::OnionRealm0HopData {
-                                       short_channel_id: last_short_channel_id,
-                                       amt_to_forward: value_msat,
-                                       outgoing_cltv_value: cltv,
-                               },
-                               hmac: [0; 32],
-                       };
-                       cur_value_msat += hop.fee_msat;
-                       if cur_value_msat >= 21000000 * 100000000 * 1000 {
-                               return Err(APIError::RouteError{err: "Channel fees overflowed?!"});
-                       }
-                       cur_cltv += hop.cltv_expiry_delta as u32;
-                       if cur_cltv >= 500000000 {
-                               return Err(APIError::RouteError{err: "Channel CLTV overflowed?!"});
-                       }
-                       last_short_channel_id = hop.short_channel_id;
-               }
-               Ok((res, cur_value_msat, cur_cltv))
-       }
-
-       #[inline]
-       fn shift_arr_right(arr: &mut [u8; 20*65]) {
-               unsafe {
-                       ptr::copy(arr[0..].as_ptr(), arr[65..].as_mut_ptr(), 19*65);
-               }
-               for i in 0..65 {
-                       arr[i] = 0;
-               }
-       }
-
-       #[inline]
-       fn xor_bufs(dst: &mut[u8], src: &[u8]) {
-               assert_eq!(dst.len(), src.len());
-
-               for i in 0..dst.len() {
-                       dst[i] ^= src[i];
-               }
-       }
-
-       const ZERO:[u8; 21*65] = [0; 21*65];
-       fn construct_onion_packet(mut payloads: Vec<msgs::OnionHopData>, onion_keys: Vec<OnionKeys>, associated_data: &PaymentHash) -> msgs::OnionPacket {
-               let mut buf = Vec::with_capacity(21*65);
-               buf.resize(21*65, 0);
-
-               let filler = {
-                       let iters = payloads.len() - 1;
-                       let end_len = iters * 65;
-                       let mut res = Vec::with_capacity(end_len);
-                       res.resize(end_len, 0);
-
-                       for (i, keys) in onion_keys.iter().enumerate() {
-                               if i == payloads.len() - 1 { continue; }
-                               let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
-                               chacha.process(&ChannelManager::ZERO, &mut buf); // We don't have a seek function :(
-                               ChannelManager::xor_bufs(&mut res[0..(i + 1)*65], &buf[(20 - i)*65..21*65]);
-                       }
-                       res
-               };
-
-               let mut packet_data = [0; 20*65];
-               let mut hmac_res = [0; 32];
-
-               for (i, (payload, keys)) in payloads.iter_mut().zip(onion_keys.iter()).rev().enumerate() {
-                       ChannelManager::shift_arr_right(&mut packet_data);
-                       payload.hmac = hmac_res;
-                       packet_data[0..65].copy_from_slice(&payload.encode()[..]);
-
-                       let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
-                       chacha.process(&packet_data, &mut buf[0..20*65]);
-                       packet_data[..].copy_from_slice(&buf[0..20*65]);
-
-                       if i == 0 {
-                               packet_data[20*65 - filler.len()..20*65].copy_from_slice(&filler[..]);
-                       }
-
-                       let mut hmac = HmacEngine::<Sha256>::new(&keys.mu);
-                       hmac.input(&packet_data);
-                       hmac.input(&associated_data.0[..]);
-                       hmac_res = Hmac::from_engine(hmac).into_inner();
-               }
-
-               msgs::OnionPacket{
-                       version: 0,
-                       public_key: Ok(onion_keys.first().unwrap().ephemeral_pubkey),
-                       hop_data: packet_data,
-                       hmac: hmac_res,
-               }
-       }
-
-       /// Encrypts a failure packet. raw_packet can either be a
-       /// msgs::DecodedOnionErrorPacket.encode() result or a msgs::OnionErrorPacket.data element.
-       fn encrypt_failure_packet(shared_secret: &[u8], raw_packet: &[u8]) -> msgs::OnionErrorPacket {
-               let ammag = ChannelManager::gen_ammag_from_shared_secret(&shared_secret);
-
-               let mut packet_crypted = Vec::with_capacity(raw_packet.len());
-               packet_crypted.resize(raw_packet.len(), 0);
-               let mut chacha = ChaCha20::new(&ammag, &[0u8; 8]);
-               chacha.process(&raw_packet, &mut packet_crypted[..]);
-               msgs::OnionErrorPacket {
-                       data: packet_crypted,
-               }
-       }
-
-       fn build_failure_packet(shared_secret: &[u8], failure_type: u16, failure_data: &[u8]) -> msgs::DecodedOnionErrorPacket {
-               assert_eq!(shared_secret.len(), 32);
-               assert!(failure_data.len() <= 256 - 2);
-
-               let um = ChannelManager::gen_um_from_shared_secret(&shared_secret);
-
-               let failuremsg = {
-                       let mut res = Vec::with_capacity(2 + failure_data.len());
-                       res.push(((failure_type >> 8) & 0xff) as u8);
-                       res.push(((failure_type >> 0) & 0xff) as u8);
-                       res.extend_from_slice(&failure_data[..]);
-                       res
-               };
-               let pad = {
-                       let mut res = Vec::with_capacity(256 - 2 - failure_data.len());
-                       res.resize(256 - 2 - failure_data.len(), 0);
-                       res
-               };
-               let mut packet = msgs::DecodedOnionErrorPacket {
-                       hmac: [0; 32],
-                       failuremsg: failuremsg,
-                       pad: pad,
-               };
-
-               let mut hmac = HmacEngine::<Sha256>::new(&um);
-               hmac.input(&packet.encode()[32..]);
-               packet.hmac = Hmac::from_engine(hmac).into_inner();
-
-               packet
-       }
-
-       #[inline]
-       fn build_first_hop_failure_packet(shared_secret: &[u8], failure_type: u16, failure_data: &[u8]) -> msgs::OnionErrorPacket {
-               let failure_packet = ChannelManager::build_failure_packet(shared_secret, failure_type, failure_data);
-               ChannelManager::encrypt_failure_packet(shared_secret, &failure_packet.encode()[..])
-       }
-
+       const ZERO:[u8; 65] = [0; 65];
        fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> (PendingHTLCStatus, MutexGuard<ChannelHolder>) {
                macro_rules! return_malformed_err {
                        ($msg: expr, $err_code: expr) => {
@@ -966,7 +724,7 @@ impl ChannelManager {
                        arr.copy_from_slice(&SharedSecret::new(&self.secp_ctx, &msg.onion_routing_packet.public_key.unwrap(), &self.our_network_key)[..]);
                        arr
                };
-               let (rho, mu) = ChannelManager::gen_rho_mu_from_shared_secret(&shared_secret);
+               let (rho, mu) = onion_utils::gen_rho_mu_from_shared_secret(&shared_secret);
 
                if msg.onion_routing_packet.version != 0 {
                        //TODO: Spec doesn't indicate if we should only hash hop_data here (and in other
@@ -978,7 +736,6 @@ impl ChannelManager {
                        return_malformed_err!("Unknown onion packet version", 0x8000 | 0x4000 | 4);
                }
 
-
                let mut hmac = HmacEngine::<Sha256>::new(&mu);
                hmac.input(&msg.onion_routing_packet.hop_data);
                hmac.input(&msg.payment_hash.0[..]);
@@ -997,7 +754,7 @@ impl ChannelManager {
                                        return (PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
                                                channel_id: msg.channel_id,
                                                htlc_id: msg.htlc_id,
-                                               reason: ChannelManager::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
+                                               reason: onion_utils::build_first_hop_failure_packet(&shared_secret, $err_code, $data),
                                        })), channel_state.unwrap());
                                }
                        }
@@ -1050,7 +807,7 @@ impl ChannelManager {
                        } else {
                                let mut new_packet_data = [0; 20*65];
                                chacha.process(&msg.onion_routing_packet.hop_data[65..], &mut new_packet_data[0..19*65]);
-                               chacha.process(&ChannelManager::ZERO[0..65], &mut new_packet_data[19*65..]);
+                               chacha.process(&ChannelManager::ZERO[..], &mut new_packet_data[19*65..]);
 
                                let mut new_pubkey = msg.onion_routing_packet.public_key.unwrap();
 
@@ -1217,10 +974,10 @@ impl ChannelManager {
 
                let cur_height = self.latest_block_height.load(Ordering::Acquire) as u32 + 1;
 
-               let onion_keys = secp_call!(ChannelManager::construct_onion_keys(&self.secp_ctx, &route, &session_priv),
+               let onion_keys = secp_call!(onion_utils::construct_onion_keys(&self.secp_ctx, &route, &session_priv),
                                APIError::RouteError{err: "Pubkey along hop was maliciously selected"});
-               let (onion_payloads, htlc_msat, htlc_cltv) = ChannelManager::build_onion_payloads(&route, cur_height)?;
-               let onion_packet = ChannelManager::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
+               let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height)?;
+               let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
 
                let _ = self.total_consistency_lock.read().unwrap();
 
@@ -1578,12 +1335,12 @@ impl ChannelManager {
                                let err_packet = match onion_error {
                                        HTLCFailReason::Reason { failure_code, data } => {
                                                log_trace!(self, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
-                                               let packet = ChannelManager::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
-                                               ChannelManager::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
+                                               let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
+                                               onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
                                        },
                                        HTLCFailReason::ErrorPacket { err } => {
                                                log_trace!(self, "Failing HTLC with payment_hash {} backwards with pre-built ErrorPacket", log_bytes!(payment_hash.0));
-                                               ChannelManager::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
+                                               onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &err.data)
                                        }
                                };
 
@@ -2055,7 +1812,7 @@ impl ChannelManager {
                                                                // that we can't return |20 for an inbound channel being disabled.
                                                                // This probably needs a spec update but should definitely be
                                                                // allowed.
-                                                               ChannelManager::build_first_hop_failure_packet(&incoming_shared_secret, 0x1000|20, &{
+                                                               onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x1000|20, &{
                                                                        let mut res = Vec::with_capacity(8 + 128);
                                                                        res.extend_from_slice(&byte_utils::be16_to_array(update.contents.flags));
                                                                        res.extend_from_slice(&update.encode_with_len()[..]);
@@ -2067,7 +1824,7 @@ impl ChannelManager {
                                                                // over the channel back to themselves (cause no one else should
                                                                // know the short_id is a lightning channel yet). We should have no
                                                                // problem just calling this unknown_next_peer
-                                                               ChannelManager::build_first_hop_failure_packet(&incoming_shared_secret, 0x4000|10, &[])
+                                                               onion_utils::build_first_hop_failure_packet(&incoming_shared_secret, 0x4000|10, &[])
                                                        },
                                                }));
                                        }
@@ -2110,14 +1867,14 @@ impl ChannelManager {
                        let mut is_from_final_node = false;
 
                        // Handle packed channel/node updates for passing back for the route handler
-                       Self::construct_onion_keys_callback(&self.secp_ctx, route, session_priv, |shared_secret, _, _, route_hop| {
+                       onion_utils::construct_onion_keys_callback(&self.secp_ctx, route, session_priv, |shared_secret, _, _, route_hop| {
                                next_route_hop_ix += 1;
                                if res.is_some() { return; }
 
                                let amt_to_forward = htlc_msat - route_hop.fee_msat;
                                htlc_msat = amt_to_forward;
 
-                               let ammag = ChannelManager::gen_ammag_from_shared_secret(&shared_secret[..]);
+                               let ammag = onion_utils::gen_ammag_from_shared_secret(&shared_secret[..]);
 
                                let mut decryption_tmp = Vec::with_capacity(packet_decrypted.len());
                                decryption_tmp.resize(packet_decrypted.len(), 0);
@@ -2128,7 +1885,7 @@ impl ChannelManager {
                                is_from_final_node = route.hops.last().unwrap().pubkey == route_hop.pubkey;
 
                                if let Ok(err_packet) = msgs::DecodedOnionErrorPacket::read(&mut Cursor::new(&packet_decrypted)) {
-                                       let um = ChannelManager::gen_um_from_shared_secret(&shared_secret[..]);
+                                       let um = onion_utils::gen_um_from_shared_secret(&shared_secret[..]);
                                        let mut hmac = HmacEngine::<Sha256>::new(&um);
                                        hmac.input(&err_packet.encode()[32..]);
 
@@ -3329,9 +3086,10 @@ mod tests {
        use chain::keysinterface::{KeysInterface, SpendableOutputDescriptor};
        use chain::keysinterface;
        use ln::channel::{COMMITMENT_TX_BASE_WEIGHT, COMMITMENT_TX_WEIGHT_PER_HTLC};
-       use ln::channelmanager::{ChannelManager,ChannelManagerReadArgs,OnionKeys,RAACommitmentOrder, PaymentPreimage, PaymentHash};
+       use ln::channelmanager::{ChannelManager,ChannelManagerReadArgs,RAACommitmentOrder, PaymentPreimage, PaymentHash};
        use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, CLTV_CLAIM_BUFFER, HTLC_FAIL_TIMEOUT_BLOCKS, ManyChannelMonitor};
        use ln::channel::{ACCEPTED_HTLC_SCRIPT_WEIGHT, OFFERED_HTLC_SCRIPT_WEIGHT};
+       use ln::onion_utils;
        use ln::router::{Route, RouteHop, Router};
        use ln::msgs;
        use ln::msgs::{ChannelMessageHandler,RoutingMessageHandler,HTLCFailChannelUpdate};
@@ -3356,8 +3114,6 @@ mod tests {
        use bitcoin_hashes::sha256::Hash as Sha256;
        use bitcoin_hashes::Hash;
 
-       use hex;
-
        use secp256k1::{Secp256k1, Message};
        use secp256k1::key::{PublicKey,SecretKey};
 
@@ -3372,156 +3128,6 @@ mod tests {
        use std::time::Instant;
        use std::mem;
 
-       fn build_test_onion_keys() -> Vec<OnionKeys> {
-               // Keys from BOLT 4, used in both test vector tests
-               let secp_ctx = Secp256k1::new();
-
-               let route = Route {
-                       hops: vec!(
-                                       RouteHop {
-                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
-                                       },
-                                       RouteHop {
-                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
-                                       },
-                                       RouteHop {
-                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
-                                       },
-                                       RouteHop {
-                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]).unwrap(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
-                                       },
-                                       RouteHop {
-                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("02edabbd16b41c8371b92ef2f04c1185b4f03b6dcd52ba9b78d9d7c89c8f221145").unwrap()[..]).unwrap(),
-                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
-                                       },
-                       ),
-               };
-
-               let session_priv = SecretKey::from_slice(&secp_ctx, &hex::decode("4141414141414141414141414141414141414141414141414141414141414141").unwrap()[..]).unwrap();
-
-               let onion_keys = ChannelManager::construct_onion_keys(&secp_ctx, &route, &session_priv).unwrap();
-               assert_eq!(onion_keys.len(), route.hops.len());
-               onion_keys
-       }
-
-       #[test]
-       fn onion_vectors() {
-               // Packet creation test vectors from BOLT 4
-               let onion_keys = build_test_onion_keys();
-
-               assert_eq!(onion_keys[0].shared_secret[..], hex::decode("53eb63ea8a3fec3b3cd433b85cd62a4b145e1dda09391b348c4e1cd36a03ea66").unwrap()[..]);
-               assert_eq!(onion_keys[0].blinding_factor[..], hex::decode("2ec2e5da605776054187180343287683aa6a51b4b1c04d6dd49c45d8cffb3c36").unwrap()[..]);
-               assert_eq!(onion_keys[0].ephemeral_pubkey.serialize()[..], hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]);
-               assert_eq!(onion_keys[0].rho, hex::decode("ce496ec94def95aadd4bec15cdb41a740c9f2b62347c4917325fcc6fb0453986").unwrap()[..]);
-               assert_eq!(onion_keys[0].mu, hex::decode("b57061dc6d0a2b9f261ac410c8b26d64ac5506cbba30267a649c28c179400eba").unwrap()[..]);
-
-               assert_eq!(onion_keys[1].shared_secret[..], hex::decode("a6519e98832a0b179f62123b3567c106db99ee37bef036e783263602f3488fae").unwrap()[..]);
-               assert_eq!(onion_keys[1].blinding_factor[..], hex::decode("bf66c28bc22e598cfd574a1931a2bafbca09163df2261e6d0056b2610dab938f").unwrap()[..]);
-               assert_eq!(onion_keys[1].ephemeral_pubkey.serialize()[..], hex::decode("028f9438bfbf7feac2e108d677e3a82da596be706cc1cf342b75c7b7e22bf4e6e2").unwrap()[..]);
-               assert_eq!(onion_keys[1].rho, hex::decode("450ffcabc6449094918ebe13d4f03e433d20a3d28a768203337bc40b6e4b2c59").unwrap()[..]);
-               assert_eq!(onion_keys[1].mu, hex::decode("05ed2b4a3fb023c2ff5dd6ed4b9b6ea7383f5cfe9d59c11d121ec2c81ca2eea9").unwrap()[..]);
-
-               assert_eq!(onion_keys[2].shared_secret[..], hex::decode("3a6b412548762f0dbccce5c7ae7bb8147d1caf9b5471c34120b30bc9c04891cc").unwrap()[..]);
-               assert_eq!(onion_keys[2].blinding_factor[..], hex::decode("a1f2dadd184eb1627049673f18c6325814384facdee5bfd935d9cb031a1698a5").unwrap()[..]);
-               assert_eq!(onion_keys[2].ephemeral_pubkey.serialize()[..], hex::decode("03bfd8225241ea71cd0843db7709f4c222f62ff2d4516fd38b39914ab6b83e0da0").unwrap()[..]);
-               assert_eq!(onion_keys[2].rho, hex::decode("11bf5c4f960239cb37833936aa3d02cea82c0f39fd35f566109c41f9eac8deea").unwrap()[..]);
-               assert_eq!(onion_keys[2].mu, hex::decode("caafe2820fa00eb2eeb78695ae452eba38f5a53ed6d53518c5c6edf76f3f5b78").unwrap()[..]);
-
-               assert_eq!(onion_keys[3].shared_secret[..], hex::decode("21e13c2d7cfe7e18836df50872466117a295783ab8aab0e7ecc8c725503ad02d").unwrap()[..]);
-               assert_eq!(onion_keys[3].blinding_factor[..], hex::decode("7cfe0b699f35525029ae0fa437c69d0f20f7ed4e3916133f9cacbb13c82ff262").unwrap()[..]);
-               assert_eq!(onion_keys[3].ephemeral_pubkey.serialize()[..], hex::decode("031dde6926381289671300239ea8e57ffaf9bebd05b9a5b95beaf07af05cd43595").unwrap()[..]);
-               assert_eq!(onion_keys[3].rho, hex::decode("cbe784ab745c13ff5cffc2fbe3e84424aa0fd669b8ead4ee562901a4a4e89e9e").unwrap()[..]);
-               assert_eq!(onion_keys[3].mu, hex::decode("5052aa1b3d9f0655a0932e50d42f0c9ba0705142c25d225515c45f47c0036ee9").unwrap()[..]);
-
-               assert_eq!(onion_keys[4].shared_secret[..], hex::decode("b5756b9b542727dbafc6765a49488b023a725d631af688fc031217e90770c328").unwrap()[..]);
-               assert_eq!(onion_keys[4].blinding_factor[..], hex::decode("c96e00dddaf57e7edcd4fb5954be5b65b09f17cb6d20651b4e90315be5779205").unwrap()[..]);
-               assert_eq!(onion_keys[4].ephemeral_pubkey.serialize()[..], hex::decode("03a214ebd875aab6ddfd77f22c5e7311d7f77f17a169e599f157bbcdae8bf071f4").unwrap()[..]);
-               assert_eq!(onion_keys[4].rho, hex::decode("034e18b8cc718e8af6339106e706c52d8df89e2b1f7e9142d996acf88df8799b").unwrap()[..]);
-               assert_eq!(onion_keys[4].mu, hex::decode("8e45e5c61c2b24cb6382444db6698727afb063adecd72aada233d4bf273d975a").unwrap()[..]);
-
-               // Test vectors below are flat-out wrong: they claim to set outgoing_cltv_value to non-0 :/
-               let payloads = vec!(
-                       msgs::OnionHopData {
-                               realm: 0,
-                               data: msgs::OnionRealm0HopData {
-                                       short_channel_id: 0,
-                                       amt_to_forward: 0,
-                                       outgoing_cltv_value: 0,
-                               },
-                               hmac: [0; 32],
-                       },
-                       msgs::OnionHopData {
-                               realm: 0,
-                               data: msgs::OnionRealm0HopData {
-                                       short_channel_id: 0x0101010101010101,
-                                       amt_to_forward: 0x0100000001,
-                                       outgoing_cltv_value: 0,
-                               },
-                               hmac: [0; 32],
-                       },
-                       msgs::OnionHopData {
-                               realm: 0,
-                               data: msgs::OnionRealm0HopData {
-                                       short_channel_id: 0x0202020202020202,
-                                       amt_to_forward: 0x0200000002,
-                                       outgoing_cltv_value: 0,
-                               },
-                               hmac: [0; 32],
-                       },
-                       msgs::OnionHopData {
-                               realm: 0,
-                               data: msgs::OnionRealm0HopData {
-                                       short_channel_id: 0x0303030303030303,
-                                       amt_to_forward: 0x0300000003,
-                                       outgoing_cltv_value: 0,
-                               },
-                               hmac: [0; 32],
-                       },
-                       msgs::OnionHopData {
-                               realm: 0,
-                               data: msgs::OnionRealm0HopData {
-                                       short_channel_id: 0x0404040404040404,
-                                       amt_to_forward: 0x0400000004,
-                                       outgoing_cltv_value: 0,
-                               },
-                               hmac: [0; 32],
-                       },
-               );
-
-               let packet = ChannelManager::construct_onion_packet(payloads, onion_keys, &PaymentHash([0x42; 32]));
-               // Just check the final packet encoding, as it includes all the per-hop vectors in it
-               // anyway...
-               assert_eq!(packet.encode(), hex::decode("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").unwrap());
-       }
-
-       #[test]
-       fn test_failure_packet_onion() {
-               // Returning Errors test vectors from BOLT 4
-
-               let onion_keys = build_test_onion_keys();
-               let onion_error = ChannelManager::build_failure_packet(&onion_keys[4].shared_secret[..], 0x2002, &[0; 0]);
-               assert_eq!(onion_error.encode(), hex::decode("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").unwrap());
-
-               let onion_packet_1 = ChannelManager::encrypt_failure_packet(&onion_keys[4].shared_secret[..], &onion_error.encode()[..]);
-               assert_eq!(onion_packet_1.data, hex::decode("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").unwrap());
-
-               let onion_packet_2 = ChannelManager::encrypt_failure_packet(&onion_keys[3].shared_secret[..], &onion_packet_1.data[..]);
-               assert_eq!(onion_packet_2.data, hex::decode("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").unwrap());
-
-               let onion_packet_3 = ChannelManager::encrypt_failure_packet(&onion_keys[2].shared_secret[..], &onion_packet_2.data[..]);
-               assert_eq!(onion_packet_3.data, hex::decode("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").unwrap());
-
-               let onion_packet_4 = ChannelManager::encrypt_failure_packet(&onion_keys[1].shared_secret[..], &onion_packet_3.data[..]);
-               assert_eq!(onion_packet_4.data, hex::decode("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").unwrap());
-
-               let onion_packet_5 = ChannelManager::encrypt_failure_packet(&onion_keys[0].shared_secret[..], &onion_packet_4.data[..]);
-               assert_eq!(onion_packet_5.data, hex::decode("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").unwrap());
-       }
-
        fn confirm_transaction(chain: &chaininterface::ChainWatchInterfaceUtil, tx: &Transaction, chan_id: u32) {
                assert!(chain.does_match_tx(tx));
                let mut header = BlockHeader { version: 0x20000000, prev_blockhash: Default::default(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
@@ -5592,9 +5198,9 @@ mod tests {
                        }).expect("RNG is bad!");
 
                        let cur_height = nodes[0].node.latest_block_height.load(Ordering::Acquire) as u32 + 1;
-                       let onion_keys = ChannelManager::construct_onion_keys(&secp_ctx, &route, &session_priv).unwrap();
-                       let (onion_payloads, htlc_msat, htlc_cltv) = ChannelManager::build_onion_payloads(&route, cur_height).unwrap();
-                       let onion_packet = ChannelManager::construct_onion_packet(onion_payloads, onion_keys, &our_payment_hash);
+                       let onion_keys = onion_utils::construct_onion_keys(&secp_ctx, &route, &session_priv).unwrap();
+                       let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height).unwrap();
+                       let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, &our_payment_hash);
                        let msg = msgs::UpdateAddHTLC {
                                channel_id: chan_1.2,
                                htlc_id,
@@ -9648,20 +9254,20 @@ mod tests {
                run_onion_failure_test("invalid_realm", 0, &nodes, &route, &payment_hash, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
                        let cur_height = nodes[0].node.latest_block_height.load(Ordering::Acquire) as u32 + 1;
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       let (mut onion_payloads, _htlc_msat, _htlc_cltv) = ChannelManager::build_onion_payloads(&route, cur_height).unwrap();
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       let (mut onion_payloads, _htlc_msat, _htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height).unwrap();
                        onion_payloads[0].realm = 3;
-                       msg.onion_routing_packet = ChannelManager::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
+                       msg.onion_routing_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
                }, ||{}, true, Some(PERM|1), Some(msgs::HTLCFailChannelUpdate::ChannelClosed{short_channel_id: channels[1].0.contents.short_channel_id, is_permanent: true}));//XXX incremented channels idx here
 
                // final node failure
                run_onion_failure_test("invalid_realm", 3, &nodes, &route, &payment_hash, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
                        let cur_height = nodes[0].node.latest_block_height.load(Ordering::Acquire) as u32 + 1;
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       let (mut onion_payloads, _htlc_msat, _htlc_cltv) = ChannelManager::build_onion_payloads(&route, cur_height).unwrap();
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       let (mut onion_payloads, _htlc_msat, _htlc_cltv) = onion_utils::build_onion_payloads(&route, cur_height).unwrap();
                        onion_payloads[1].realm = 3;
-                       msg.onion_routing_packet = ChannelManager::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
+                       msg.onion_routing_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
                }, ||{}, false, Some(PERM|1), Some(msgs::HTLCFailChannelUpdate::ChannelClosed{short_channel_id: channels[1].0.contents.short_channel_id, is_permanent: true}));
 
                // the following three with run_onion_failure_test_with_fail_intercept() test only the origin node
@@ -9673,16 +9279,16 @@ mod tests {
                }, |msg| {
                        // and tamper returing error message
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], NODE|2, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], NODE|2, &[0;0]);
                }, ||{}, true, Some(NODE|2), Some(msgs::HTLCFailChannelUpdate::NodeFailure{node_id: route.hops[0].pubkey, is_permanent: false}));
 
                // final node failure
                run_onion_failure_test_with_fail_intercept("temporary_node_failure", 200, &nodes, &route, &payment_hash, |_msg| {}, |msg| {
                        // and tamper returing error message
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[1].shared_secret[..], NODE|2, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[1].shared_secret[..], NODE|2, &[0;0]);
                }, ||{
                        nodes[2].node.fail_htlc_backwards(&payment_hash, 0);
                }, true, Some(NODE|2), Some(msgs::HTLCFailChannelUpdate::NodeFailure{node_id: route.hops[1].pubkey, is_permanent: false}));
@@ -9692,15 +9298,15 @@ mod tests {
                        msg.amount_msat -= 1;
                }, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|NODE|2, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|NODE|2, &[0;0]);
                }, ||{}, true, Some(PERM|NODE|2), Some(msgs::HTLCFailChannelUpdate::NodeFailure{node_id: route.hops[0].pubkey, is_permanent: true}));
 
                // final node failure
                run_onion_failure_test_with_fail_intercept("permanent_node_failure", 200, &nodes, &route, &payment_hash, |_msg| {}, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[1].shared_secret[..], PERM|NODE|2, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[1].shared_secret[..], PERM|NODE|2, &[0;0]);
                }, ||{
                        nodes[2].node.fail_htlc_backwards(&payment_hash, 0);
                }, false, Some(PERM|NODE|2), Some(msgs::HTLCFailChannelUpdate::NodeFailure{node_id: route.hops[1].pubkey, is_permanent: true}));
@@ -9710,8 +9316,8 @@ mod tests {
                        msg.amount_msat -= 1;
                }, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|NODE|3, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|NODE|3, &[0;0]);
                }, ||{
                        nodes[2].node.fail_htlc_backwards(&payment_hash, 0);
                }, true, Some(PERM|NODE|3), Some(msgs::HTLCFailChannelUpdate::NodeFailure{node_id: route.hops[0].pubkey, is_permanent: true}));
@@ -9719,8 +9325,8 @@ mod tests {
                // final node failure
                run_onion_failure_test_with_fail_intercept("required_node_feature_missing", 200, &nodes, &route, &payment_hash, |_msg| {}, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[1].shared_secret[..], PERM|NODE|3, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[1].shared_secret[..], PERM|NODE|3, &[0;0]);
                }, ||{
                        nodes[2].node.fail_htlc_backwards(&payment_hash, 0);
                }, false, Some(PERM|NODE|3), Some(msgs::HTLCFailChannelUpdate::NodeFailure{node_id: route.hops[1].pubkey, is_permanent: true}));
@@ -9738,16 +9344,16 @@ mod tests {
                        msg.amount_msat -= 1;
                }, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], UPDATE|7, &ChannelUpdate::dummy().encode_with_len()[..]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], UPDATE|7, &ChannelUpdate::dummy().encode_with_len()[..]);
                }, ||{}, true, Some(UPDATE|7), Some(msgs::HTLCFailChannelUpdate::ChannelUpdateMessage{msg: ChannelUpdate::dummy()}));
 
                run_onion_failure_test_with_fail_intercept("permanent_channel_failure", 100, &nodes, &route, &payment_hash, |msg| {
                        msg.amount_msat -= 1;
                }, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|8, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|8, &[0;0]);
                        // short_channel_id from the processing node
                }, ||{}, true, Some(PERM|8), Some(msgs::HTLCFailChannelUpdate::ChannelClosed{short_channel_id: channels[1].0.contents.short_channel_id, is_permanent: true}));
 
@@ -9755,8 +9361,8 @@ mod tests {
                        msg.amount_msat -= 1;
                }, |msg| {
                        let session_priv = SecretKey::from_slice(&::secp256k1::Secp256k1::without_caps(), &[3; 32]).unwrap();
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       msg.reason = ChannelManager::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|9, &[0;0]);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       msg.reason = onion_utils::build_first_hop_failure_packet(&onion_keys[0].shared_secret[..], PERM|9, &[0;0]);
                        // short_channel_id from the processing node
                }, ||{}, true, Some(PERM|9), Some(msgs::HTLCFailChannelUpdate::ChannelClosed{short_channel_id: channels[1].0.contents.short_channel_id, is_permanent: true}));
 
@@ -9827,9 +9433,9 @@ mod tests {
                        let mut route = route.clone();
                        let height = 1;
                        route.hops[1].cltv_expiry_delta += CLTV_FAR_FAR_AWAY + route.hops[0].cltv_expiry_delta + 1;
-                       let onion_keys = ChannelManager::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
-                       let (onion_payloads, _, htlc_cltv) = ChannelManager::build_onion_payloads(&route, height).unwrap();
-                       let onion_packet = ChannelManager::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
+                       let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route, &session_priv).unwrap();
+                       let (onion_payloads, _, htlc_cltv) = onion_utils::build_onion_payloads(&route, height).unwrap();
+                       let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, &payment_hash);
                        msg.cltv_expiry = htlc_cltv;
                        msg.onion_routing_packet = onion_packet;
                }, ||{}, true, Some(21), None);
index ca8acd50dde7a865c19686fb4e7f8d89d7b8031a..14ef3b69822d775d80e24fbd467149146bc7a537 100644 (file)
@@ -22,3 +22,4 @@ pub(crate) mod peer_channel_encryptor;
 
 mod channel;
 mod chan_utils;
+mod onion_utils;
diff --git a/src/ln/onion_utils.rs b/src/ln/onion_utils.rs
new file mode 100644 (file)
index 0000000..85f98ff
--- /dev/null
@@ -0,0 +1,427 @@
+use ln::channelmanager::PaymentHash;
+use ln::msgs;
+use ln::router::{Route,RouteHop};
+use util::internal_traits;
+use util::chacha20::ChaCha20;
+use util::errors::APIError;
+use util::ser::Writeable;
+
+use bitcoin_hashes::{Hash, HashEngine};
+use bitcoin_hashes::hmac::{Hmac, HmacEngine};
+use bitcoin_hashes::sha256::Hash as Sha256;
+
+use secp256k1::key::{SecretKey,PublicKey};
+use secp256k1::Secp256k1;
+use secp256k1::ecdh::SharedSecret;
+use secp256k1;
+
+use std::ptr;
+
+pub(super) struct OnionKeys {
+       #[cfg(test)]
+       pub(super) shared_secret: SharedSecret,
+       #[cfg(test)]
+       pub(super) blinding_factor: [u8; 32],
+       pub(super) ephemeral_pubkey: PublicKey,
+       pub(super) rho: [u8; 32],
+       pub(super) mu: [u8; 32],
+}
+
+#[inline]
+pub(super) fn gen_rho_mu_from_shared_secret(shared_secret: &[u8]) -> ([u8; 32], [u8; 32]) {
+       assert_eq!(shared_secret.len(), 32);
+       ({
+               let mut hmac = HmacEngine::<Sha256>::new(&[0x72, 0x68, 0x6f]); // rho
+               hmac.input(&shared_secret[..]);
+               Hmac::from_engine(hmac).into_inner()
+       },
+       {
+               let mut hmac = HmacEngine::<Sha256>::new(&[0x6d, 0x75]); // mu
+               hmac.input(&shared_secret[..]);
+               Hmac::from_engine(hmac).into_inner()
+       })
+}
+
+#[inline]
+pub(super) fn gen_um_from_shared_secret(shared_secret: &[u8]) -> [u8; 32] {
+       assert_eq!(shared_secret.len(), 32);
+       let mut hmac = HmacEngine::<Sha256>::new(&[0x75, 0x6d]); // um
+       hmac.input(&shared_secret[..]);
+       Hmac::from_engine(hmac).into_inner()
+}
+
+#[inline]
+pub(super) fn gen_ammag_from_shared_secret(shared_secret: &[u8]) -> [u8; 32] {
+       assert_eq!(shared_secret.len(), 32);
+       let mut hmac = HmacEngine::<Sha256>::new(&[0x61, 0x6d, 0x6d, 0x61, 0x67]); // ammag
+       hmac.input(&shared_secret[..]);
+       Hmac::from_engine(hmac).into_inner()
+}
+
+// can only fail if an intermediary hop has an invalid public key or session_priv is invalid
+#[inline]
+pub(super) fn construct_onion_keys_callback<T: secp256k1::Signing, FType: FnMut(SharedSecret, [u8; 32], PublicKey, &RouteHop)> (secp_ctx: &Secp256k1<T>, route: &Route, session_priv: &SecretKey, mut callback: FType) -> Result<(), secp256k1::Error> {
+       let mut blinded_priv = session_priv.clone();
+       let mut blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
+
+       for hop in route.hops.iter() {
+               let shared_secret = SharedSecret::new(secp_ctx, &hop.pubkey, &blinded_priv);
+
+               let mut sha = Sha256::engine();
+               sha.input(&blinded_pub.serialize()[..]);
+               sha.input(&shared_secret[..]);
+               let blinding_factor = Sha256::from_engine(sha).into_inner();
+
+               let ephemeral_pubkey = blinded_pub;
+
+               blinded_priv.mul_assign(secp_ctx, &SecretKey::from_slice(secp_ctx, &blinding_factor)?)?;
+               blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
+
+               callback(shared_secret, blinding_factor, ephemeral_pubkey, hop);
+       }
+
+       Ok(())
+}
+
+// can only fail if an intermediary hop has an invalid public key or session_priv is invalid
+pub(super) fn construct_onion_keys<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, route: &Route, session_priv: &SecretKey) -> Result<Vec<OnionKeys>, secp256k1::Error> {
+       let mut res = Vec::with_capacity(route.hops.len());
+
+       construct_onion_keys_callback(secp_ctx, route, session_priv, |shared_secret, _blinding_factor, ephemeral_pubkey, _| {
+               let (rho, mu) = gen_rho_mu_from_shared_secret(&shared_secret[..]);
+
+               res.push(OnionKeys {
+                       #[cfg(test)]
+                       shared_secret,
+                       #[cfg(test)]
+                       blinding_factor: _blinding_factor,
+                       ephemeral_pubkey,
+                       rho,
+                       mu,
+               });
+       })?;
+
+       Ok(res)
+}
+
+/// returns the hop data, as well as the first-hop value_msat and CLTV value we should send.
+pub(super) fn build_onion_payloads(route: &Route, starting_htlc_offset: u32) -> Result<(Vec<msgs::OnionHopData>, u64, u32), APIError> {
+       let mut cur_value_msat = 0u64;
+       let mut cur_cltv = starting_htlc_offset;
+       let mut last_short_channel_id = 0;
+       let mut res: Vec<msgs::OnionHopData> = Vec::with_capacity(route.hops.len());
+       internal_traits::test_no_dealloc::<msgs::OnionHopData>(None);
+       unsafe { res.set_len(route.hops.len()); }
+
+       for (idx, hop) in route.hops.iter().enumerate().rev() {
+               // First hop gets special values so that it can check, on receipt, that everything is
+               // exactly as it should be (and the next hop isn't trying to probe to find out if we're
+               // the intended recipient).
+               let value_msat = if cur_value_msat == 0 { hop.fee_msat } else { cur_value_msat };
+               let cltv = if cur_cltv == starting_htlc_offset { hop.cltv_expiry_delta + starting_htlc_offset } else { cur_cltv };
+               res[idx] = msgs::OnionHopData {
+                       realm: 0,
+                       data: msgs::OnionRealm0HopData {
+                               short_channel_id: last_short_channel_id,
+                               amt_to_forward: value_msat,
+                               outgoing_cltv_value: cltv,
+                       },
+                       hmac: [0; 32],
+               };
+               cur_value_msat += hop.fee_msat;
+               if cur_value_msat >= 21000000 * 100000000 * 1000 {
+                       return Err(APIError::RouteError{err: "Channel fees overflowed?!"});
+               }
+               cur_cltv += hop.cltv_expiry_delta as u32;
+               if cur_cltv >= 500000000 {
+                       return Err(APIError::RouteError{err: "Channel CLTV overflowed?!"});
+               }
+               last_short_channel_id = hop.short_channel_id;
+       }
+       Ok((res, cur_value_msat, cur_cltv))
+}
+
+#[inline]
+fn shift_arr_right(arr: &mut [u8; 20*65]) {
+       unsafe {
+               ptr::copy(arr[0..].as_ptr(), arr[65..].as_mut_ptr(), 19*65);
+       }
+       for i in 0..65 {
+               arr[i] = 0;
+       }
+}
+
+#[inline]
+fn xor_bufs(dst: &mut[u8], src: &[u8]) {
+       assert_eq!(dst.len(), src.len());
+
+       for i in 0..dst.len() {
+               dst[i] ^= src[i];
+       }
+}
+
+const ZERO:[u8; 21*65] = [0; 21*65];
+pub(super) fn construct_onion_packet(mut payloads: Vec<msgs::OnionHopData>, onion_keys: Vec<OnionKeys>, associated_data: &PaymentHash) -> msgs::OnionPacket {
+       let mut buf = Vec::with_capacity(21*65);
+       buf.resize(21*65, 0);
+
+       let filler = {
+               let iters = payloads.len() - 1;
+               let end_len = iters * 65;
+               let mut res = Vec::with_capacity(end_len);
+               res.resize(end_len, 0);
+
+               for (i, keys) in onion_keys.iter().enumerate() {
+                       if i == payloads.len() - 1 { continue; }
+                       let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
+                       chacha.process(&ZERO, &mut buf); // We don't have a seek function :(
+                       xor_bufs(&mut res[0..(i + 1)*65], &buf[(20 - i)*65..21*65]);
+               }
+               res
+       };
+
+       let mut packet_data = [0; 20*65];
+       let mut hmac_res = [0; 32];
+
+       for (i, (payload, keys)) in payloads.iter_mut().zip(onion_keys.iter()).rev().enumerate() {
+               shift_arr_right(&mut packet_data);
+               payload.hmac = hmac_res;
+               packet_data[0..65].copy_from_slice(&payload.encode()[..]);
+
+               let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
+               chacha.process(&packet_data, &mut buf[0..20*65]);
+               packet_data[..].copy_from_slice(&buf[0..20*65]);
+
+               if i == 0 {
+                       packet_data[20*65 - filler.len()..20*65].copy_from_slice(&filler[..]);
+               }
+
+               let mut hmac = HmacEngine::<Sha256>::new(&keys.mu);
+               hmac.input(&packet_data);
+               hmac.input(&associated_data.0[..]);
+               hmac_res = Hmac::from_engine(hmac).into_inner();
+       }
+
+       msgs::OnionPacket{
+               version: 0,
+               public_key: Ok(onion_keys.first().unwrap().ephemeral_pubkey),
+               hop_data: packet_data,
+               hmac: hmac_res,
+       }
+}
+
+/// Encrypts a failure packet. raw_packet can either be a
+/// msgs::DecodedOnionErrorPacket.encode() result or a msgs::OnionErrorPacket.data element.
+pub(super) fn encrypt_failure_packet(shared_secret: &[u8], raw_packet: &[u8]) -> msgs::OnionErrorPacket {
+       let ammag = gen_ammag_from_shared_secret(&shared_secret);
+
+       let mut packet_crypted = Vec::with_capacity(raw_packet.len());
+       packet_crypted.resize(raw_packet.len(), 0);
+       let mut chacha = ChaCha20::new(&ammag, &[0u8; 8]);
+       chacha.process(&raw_packet, &mut packet_crypted[..]);
+       msgs::OnionErrorPacket {
+               data: packet_crypted,
+       }
+}
+
+pub(super) fn build_failure_packet(shared_secret: &[u8], failure_type: u16, failure_data: &[u8]) -> msgs::DecodedOnionErrorPacket {
+       assert_eq!(shared_secret.len(), 32);
+       assert!(failure_data.len() <= 256 - 2);
+
+       let um = gen_um_from_shared_secret(&shared_secret);
+
+       let failuremsg = {
+               let mut res = Vec::with_capacity(2 + failure_data.len());
+               res.push(((failure_type >> 8) & 0xff) as u8);
+               res.push(((failure_type >> 0) & 0xff) as u8);
+               res.extend_from_slice(&failure_data[..]);
+               res
+       };
+       let pad = {
+               let mut res = Vec::with_capacity(256 - 2 - failure_data.len());
+               res.resize(256 - 2 - failure_data.len(), 0);
+               res
+       };
+       let mut packet = msgs::DecodedOnionErrorPacket {
+               hmac: [0; 32],
+               failuremsg: failuremsg,
+               pad: pad,
+       };
+
+       let mut hmac = HmacEngine::<Sha256>::new(&um);
+       hmac.input(&packet.encode()[32..]);
+       packet.hmac = Hmac::from_engine(hmac).into_inner();
+
+       packet
+}
+
+#[inline]
+pub(super) fn build_first_hop_failure_packet(shared_secret: &[u8], failure_type: u16, failure_data: &[u8]) -> msgs::OnionErrorPacket {
+       let failure_packet = build_failure_packet(shared_secret, failure_type, failure_data);
+       encrypt_failure_packet(shared_secret, &failure_packet.encode()[..])
+}
+
+#[cfg(test)]
+mod tests {
+       use ln::channelmanager::PaymentHash;
+       use ln::router::{Route, RouteHop};
+       use ln::msgs;
+       use util::ser::Writeable;
+
+       use hex;
+
+       use secp256k1::Secp256k1;
+       use secp256k1::key::{PublicKey,SecretKey};
+
+       use super::OnionKeys;
+
+       fn build_test_onion_keys() -> Vec<OnionKeys> {
+               // Keys from BOLT 4, used in both test vector tests
+               let secp_ctx = Secp256k1::new();
+
+               let route = Route {
+                       hops: vec!(
+                                       RouteHop {
+                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
+                                       },
+                                       RouteHop {
+                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
+                                       },
+                                       RouteHop {
+                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
+                                       },
+                                       RouteHop {
+                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]).unwrap(),
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
+                                       },
+                                       RouteHop {
+                                               pubkey: PublicKey::from_slice(&secp_ctx, &hex::decode("02edabbd16b41c8371b92ef2f04c1185b4f03b6dcd52ba9b78d9d7c89c8f221145").unwrap()[..]).unwrap(),
+                                               short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0 // Test vectors are garbage and not generateble from a RouteHop, we fill in payloads manually
+                                       },
+                       ),
+               };
+
+               let session_priv = SecretKey::from_slice(&secp_ctx, &hex::decode("4141414141414141414141414141414141414141414141414141414141414141").unwrap()[..]).unwrap();
+
+               let onion_keys = super::construct_onion_keys(&secp_ctx, &route, &session_priv).unwrap();
+               assert_eq!(onion_keys.len(), route.hops.len());
+               onion_keys
+       }
+
+       #[test]
+       fn onion_vectors() {
+               // Packet creation test vectors from BOLT 4
+               let onion_keys = build_test_onion_keys();
+
+               assert_eq!(onion_keys[0].shared_secret[..], hex::decode("53eb63ea8a3fec3b3cd433b85cd62a4b145e1dda09391b348c4e1cd36a03ea66").unwrap()[..]);
+               assert_eq!(onion_keys[0].blinding_factor[..], hex::decode("2ec2e5da605776054187180343287683aa6a51b4b1c04d6dd49c45d8cffb3c36").unwrap()[..]);
+               assert_eq!(onion_keys[0].ephemeral_pubkey.serialize()[..], hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]);
+               assert_eq!(onion_keys[0].rho, hex::decode("ce496ec94def95aadd4bec15cdb41a740c9f2b62347c4917325fcc6fb0453986").unwrap()[..]);
+               assert_eq!(onion_keys[0].mu, hex::decode("b57061dc6d0a2b9f261ac410c8b26d64ac5506cbba30267a649c28c179400eba").unwrap()[..]);
+
+               assert_eq!(onion_keys[1].shared_secret[..], hex::decode("a6519e98832a0b179f62123b3567c106db99ee37bef036e783263602f3488fae").unwrap()[..]);
+               assert_eq!(onion_keys[1].blinding_factor[..], hex::decode("bf66c28bc22e598cfd574a1931a2bafbca09163df2261e6d0056b2610dab938f").unwrap()[..]);
+               assert_eq!(onion_keys[1].ephemeral_pubkey.serialize()[..], hex::decode("028f9438bfbf7feac2e108d677e3a82da596be706cc1cf342b75c7b7e22bf4e6e2").unwrap()[..]);
+               assert_eq!(onion_keys[1].rho, hex::decode("450ffcabc6449094918ebe13d4f03e433d20a3d28a768203337bc40b6e4b2c59").unwrap()[..]);
+               assert_eq!(onion_keys[1].mu, hex::decode("05ed2b4a3fb023c2ff5dd6ed4b9b6ea7383f5cfe9d59c11d121ec2c81ca2eea9").unwrap()[..]);
+
+               assert_eq!(onion_keys[2].shared_secret[..], hex::decode("3a6b412548762f0dbccce5c7ae7bb8147d1caf9b5471c34120b30bc9c04891cc").unwrap()[..]);
+               assert_eq!(onion_keys[2].blinding_factor[..], hex::decode("a1f2dadd184eb1627049673f18c6325814384facdee5bfd935d9cb031a1698a5").unwrap()[..]);
+               assert_eq!(onion_keys[2].ephemeral_pubkey.serialize()[..], hex::decode("03bfd8225241ea71cd0843db7709f4c222f62ff2d4516fd38b39914ab6b83e0da0").unwrap()[..]);
+               assert_eq!(onion_keys[2].rho, hex::decode("11bf5c4f960239cb37833936aa3d02cea82c0f39fd35f566109c41f9eac8deea").unwrap()[..]);
+               assert_eq!(onion_keys[2].mu, hex::decode("caafe2820fa00eb2eeb78695ae452eba38f5a53ed6d53518c5c6edf76f3f5b78").unwrap()[..]);
+
+               assert_eq!(onion_keys[3].shared_secret[..], hex::decode("21e13c2d7cfe7e18836df50872466117a295783ab8aab0e7ecc8c725503ad02d").unwrap()[..]);
+               assert_eq!(onion_keys[3].blinding_factor[..], hex::decode("7cfe0b699f35525029ae0fa437c69d0f20f7ed4e3916133f9cacbb13c82ff262").unwrap()[..]);
+               assert_eq!(onion_keys[3].ephemeral_pubkey.serialize()[..], hex::decode("031dde6926381289671300239ea8e57ffaf9bebd05b9a5b95beaf07af05cd43595").unwrap()[..]);
+               assert_eq!(onion_keys[3].rho, hex::decode("cbe784ab745c13ff5cffc2fbe3e84424aa0fd669b8ead4ee562901a4a4e89e9e").unwrap()[..]);
+               assert_eq!(onion_keys[3].mu, hex::decode("5052aa1b3d9f0655a0932e50d42f0c9ba0705142c25d225515c45f47c0036ee9").unwrap()[..]);
+
+               assert_eq!(onion_keys[4].shared_secret[..], hex::decode("b5756b9b542727dbafc6765a49488b023a725d631af688fc031217e90770c328").unwrap()[..]);
+               assert_eq!(onion_keys[4].blinding_factor[..], hex::decode("c96e00dddaf57e7edcd4fb5954be5b65b09f17cb6d20651b4e90315be5779205").unwrap()[..]);
+               assert_eq!(onion_keys[4].ephemeral_pubkey.serialize()[..], hex::decode("03a214ebd875aab6ddfd77f22c5e7311d7f77f17a169e599f157bbcdae8bf071f4").unwrap()[..]);
+               assert_eq!(onion_keys[4].rho, hex::decode("034e18b8cc718e8af6339106e706c52d8df89e2b1f7e9142d996acf88df8799b").unwrap()[..]);
+               assert_eq!(onion_keys[4].mu, hex::decode("8e45e5c61c2b24cb6382444db6698727afb063adecd72aada233d4bf273d975a").unwrap()[..]);
+
+               // Test vectors below are flat-out wrong: they claim to set outgoing_cltv_value to non-0 :/
+               let payloads = vec!(
+                       msgs::OnionHopData {
+                               realm: 0,
+                               data: msgs::OnionRealm0HopData {
+                                       short_channel_id: 0,
+                                       amt_to_forward: 0,
+                                       outgoing_cltv_value: 0,
+                               },
+                               hmac: [0; 32],
+                       },
+                       msgs::OnionHopData {
+                               realm: 0,
+                               data: msgs::OnionRealm0HopData {
+                                       short_channel_id: 0x0101010101010101,
+                                       amt_to_forward: 0x0100000001,
+                                       outgoing_cltv_value: 0,
+                               },
+                               hmac: [0; 32],
+                       },
+                       msgs::OnionHopData {
+                               realm: 0,
+                               data: msgs::OnionRealm0HopData {
+                                       short_channel_id: 0x0202020202020202,
+                                       amt_to_forward: 0x0200000002,
+                                       outgoing_cltv_value: 0,
+                               },
+                               hmac: [0; 32],
+                       },
+                       msgs::OnionHopData {
+                               realm: 0,
+                               data: msgs::OnionRealm0HopData {
+                                       short_channel_id: 0x0303030303030303,
+                                       amt_to_forward: 0x0300000003,
+                                       outgoing_cltv_value: 0,
+                               },
+                               hmac: [0; 32],
+                       },
+                       msgs::OnionHopData {
+                               realm: 0,
+                               data: msgs::OnionRealm0HopData {
+                                       short_channel_id: 0x0404040404040404,
+                                       amt_to_forward: 0x0400000004,
+                                       outgoing_cltv_value: 0,
+                               },
+                               hmac: [0; 32],
+                       },
+               );
+
+               let packet = super::construct_onion_packet(payloads, onion_keys, &PaymentHash([0x42; 32]));
+               // Just check the final packet encoding, as it includes all the per-hop vectors in it
+               // anyway...
+               assert_eq!(packet.encode(), hex::decode("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").unwrap());
+       }
+
+       #[test]
+       fn test_failure_packet_onion() {
+               // Returning Errors test vectors from BOLT 4
+
+               let onion_keys = build_test_onion_keys();
+               let onion_error = super::build_failure_packet(&onion_keys[4].shared_secret[..], 0x2002, &[0; 0]);
+               assert_eq!(onion_error.encode(), hex::decode("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").unwrap());
+
+               let onion_packet_1 = super::encrypt_failure_packet(&onion_keys[4].shared_secret[..], &onion_error.encode()[..]);
+               assert_eq!(onion_packet_1.data, hex::decode("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").unwrap());
+
+               let onion_packet_2 = super::encrypt_failure_packet(&onion_keys[3].shared_secret[..], &onion_packet_1.data[..]);
+               assert_eq!(onion_packet_2.data, hex::decode("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").unwrap());
+
+               let onion_packet_3 = super::encrypt_failure_packet(&onion_keys[2].shared_secret[..], &onion_packet_2.data[..]);
+               assert_eq!(onion_packet_3.data, hex::decode("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").unwrap());
+
+               let onion_packet_4 = super::encrypt_failure_packet(&onion_keys[1].shared_secret[..], &onion_packet_3.data[..]);
+               assert_eq!(onion_packet_4.data, hex::decode("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").unwrap());
+
+               let onion_packet_5 = super::encrypt_failure_packet(&onion_keys[0].shared_secret[..], &onion_packet_4.data[..]);
+               assert_eq!(onion_packet_5.data, hex::decode("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").unwrap());
+       }
+}