Pull hmac out of OnionHopData.
[rust-lightning] / lightning / src / ln / onion_utils.rs
1 use ln::channelmanager::{PaymentHash, HTLCSource};
2 use ln::msgs;
3 use ln::router::{Route,RouteHop};
4 use util::byte_utils;
5 use util::chacha20::ChaCha20;
6 use util::errors::{self, APIError};
7 use util::ser::{Readable, Writeable};
8 use util::logger::{Logger, LogHolder};
9
10 use bitcoin_hashes::{Hash, HashEngine};
11 use bitcoin_hashes::cmp::fixed_time_eq;
12 use bitcoin_hashes::hmac::{Hmac, HmacEngine};
13 use bitcoin_hashes::sha256::Hash as Sha256;
14
15 use secp256k1::key::{SecretKey,PublicKey};
16 use secp256k1::Secp256k1;
17 use secp256k1::ecdh::SharedSecret;
18 use secp256k1;
19
20 use std::io::Cursor;
21 use std::sync::Arc;
22
23 pub(super) struct OnionKeys {
24         #[cfg(test)]
25         pub(super) shared_secret: SharedSecret,
26         #[cfg(test)]
27         pub(super) blinding_factor: [u8; 32],
28         pub(super) ephemeral_pubkey: PublicKey,
29         pub(super) rho: [u8; 32],
30         pub(super) mu: [u8; 32],
31 }
32
33 #[inline]
34 pub(super) fn gen_rho_mu_from_shared_secret(shared_secret: &[u8]) -> ([u8; 32], [u8; 32]) {
35         assert_eq!(shared_secret.len(), 32);
36         ({
37                 let mut hmac = HmacEngine::<Sha256>::new(&[0x72, 0x68, 0x6f]); // rho
38                 hmac.input(&shared_secret[..]);
39                 Hmac::from_engine(hmac).into_inner()
40         },
41         {
42                 let mut hmac = HmacEngine::<Sha256>::new(&[0x6d, 0x75]); // mu
43                 hmac.input(&shared_secret[..]);
44                 Hmac::from_engine(hmac).into_inner()
45         })
46 }
47
48 #[inline]
49 pub(super) fn gen_um_from_shared_secret(shared_secret: &[u8]) -> [u8; 32] {
50         assert_eq!(shared_secret.len(), 32);
51         let mut hmac = HmacEngine::<Sha256>::new(&[0x75, 0x6d]); // um
52         hmac.input(&shared_secret[..]);
53         Hmac::from_engine(hmac).into_inner()
54 }
55
56 #[inline]
57 pub(super) fn gen_ammag_from_shared_secret(shared_secret: &[u8]) -> [u8; 32] {
58         assert_eq!(shared_secret.len(), 32);
59         let mut hmac = HmacEngine::<Sha256>::new(&[0x61, 0x6d, 0x6d, 0x61, 0x67]); // ammag
60         hmac.input(&shared_secret[..]);
61         Hmac::from_engine(hmac).into_inner()
62 }
63
64 // can only fail if an intermediary hop has an invalid public key or session_priv is invalid
65 #[inline]
66 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> {
67         let mut blinded_priv = session_priv.clone();
68         let mut blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
69
70         for hop in route.hops.iter() {
71                 let shared_secret = SharedSecret::new(&hop.pubkey, &blinded_priv);
72
73                 let mut sha = Sha256::engine();
74                 sha.input(&blinded_pub.serialize()[..]);
75                 sha.input(&shared_secret[..]);
76                 let blinding_factor = Sha256::from_engine(sha).into_inner();
77
78                 let ephemeral_pubkey = blinded_pub;
79
80                 blinded_priv.mul_assign(&blinding_factor)?;
81                 blinded_pub = PublicKey::from_secret_key(secp_ctx, &blinded_priv);
82
83                 callback(shared_secret, blinding_factor, ephemeral_pubkey, hop);
84         }
85
86         Ok(())
87 }
88
89 // can only fail if an intermediary hop has an invalid public key or session_priv is invalid
90 pub(super) fn construct_onion_keys<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, route: &Route, session_priv: &SecretKey) -> Result<Vec<OnionKeys>, secp256k1::Error> {
91         let mut res = Vec::with_capacity(route.hops.len());
92
93         construct_onion_keys_callback(secp_ctx, route, session_priv, |shared_secret, _blinding_factor, ephemeral_pubkey, _| {
94                 let (rho, mu) = gen_rho_mu_from_shared_secret(&shared_secret[..]);
95
96                 res.push(OnionKeys {
97                         #[cfg(test)]
98                         shared_secret,
99                         #[cfg(test)]
100                         blinding_factor: _blinding_factor,
101                         ephemeral_pubkey,
102                         rho,
103                         mu,
104                 });
105         })?;
106
107         Ok(res)
108 }
109
110 /// returns the hop data, as well as the first-hop value_msat and CLTV value we should send.
111 pub(super) fn build_onion_payloads(route: &Route, starting_htlc_offset: u32) -> Result<(Vec<msgs::OnionHopData>, u64, u32), APIError> {
112         let mut cur_value_msat = 0u64;
113         let mut cur_cltv = starting_htlc_offset;
114         let mut last_short_channel_id = 0;
115         let mut res: Vec<msgs::OnionHopData> = Vec::with_capacity(route.hops.len());
116
117         for hop in route.hops.iter().rev() {
118                 // First hop gets special values so that it can check, on receipt, that everything is
119                 // exactly as it should be (and the next hop isn't trying to probe to find out if we're
120                 // the intended recipient).
121                 let value_msat = if cur_value_msat == 0 { hop.fee_msat } else { cur_value_msat };
122                 let cltv = if cur_cltv == starting_htlc_offset { hop.cltv_expiry_delta + starting_htlc_offset } else { cur_cltv };
123                 res.insert(0, msgs::OnionHopData {
124                         format: msgs::OnionHopDataFormat::Legacy,
125                         short_channel_id: last_short_channel_id,
126                         amt_to_forward: value_msat,
127                         outgoing_cltv_value: cltv,
128                 });
129                 cur_value_msat += hop.fee_msat;
130                 if cur_value_msat >= 21000000 * 100000000 * 1000 {
131                         return Err(APIError::RouteError{err: "Channel fees overflowed?!"});
132                 }
133                 cur_cltv += hop.cltv_expiry_delta as u32;
134                 if cur_cltv >= 500000000 {
135                         return Err(APIError::RouteError{err: "Channel CLTV overflowed?!"});
136                 }
137                 last_short_channel_id = hop.short_channel_id;
138         }
139         Ok((res, cur_value_msat, cur_cltv))
140 }
141
142 #[inline]
143 fn shift_arr_right(arr: &mut [u8; 20*65]) {
144         for i in (65..20*65).rev() {
145                 arr[i] = arr[i-65];
146         }
147         for i in 0..65 {
148                 arr[i] = 0;
149         }
150 }
151
152 #[inline]
153 fn xor_bufs(dst: &mut[u8], src: &[u8]) {
154         assert_eq!(dst.len(), src.len());
155
156         for i in 0..dst.len() {
157                 dst[i] ^= src[i];
158         }
159 }
160
161
162 const ZERO:[u8; 21*65] = [0; 21*65];
163 pub(super) fn construct_onion_packet(payloads: Vec<msgs::OnionHopData>, onion_keys: Vec<OnionKeys>, prng_seed: [u8; 32], associated_data: &PaymentHash) -> msgs::OnionPacket {
164         let mut packet_data = [0; 20*65];
165
166         let mut chacha = ChaCha20::new(&prng_seed, &[0; 8]);
167         chacha.process(&[0; 20*65], &mut packet_data);
168
169         construct_onion_packet_with_init_noise(payloads, onion_keys, packet_data, associated_data)
170 }
171
172 fn construct_onion_packet_with_init_noise(mut payloads: Vec<msgs::OnionHopData>, onion_keys: Vec<OnionKeys>, mut packet_data: [u8; 20*65], associated_data: &PaymentHash) -> msgs::OnionPacket {
173         let mut buf = Vec::with_capacity(21*65);
174         buf.resize(21*65, 0);
175
176         let filler = {
177                 let iters = payloads.len() - 1;
178                 let end_len = iters * 65;
179                 let mut res = Vec::with_capacity(end_len);
180                 res.resize(end_len, 0);
181
182                 for (i, keys) in onion_keys.iter().enumerate() {
183                         if i == payloads.len() - 1 { continue; }
184                         let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
185                         chacha.process(&ZERO, &mut buf); // We don't have a seek function :(
186                         xor_bufs(&mut res[0..(i + 1)*65], &buf[(20 - i)*65..21*65]);
187                 }
188                 res
189         };
190
191         let mut hmac_res = [0; 32];
192
193         for (i, (payload, keys)) in payloads.iter_mut().zip(onion_keys.iter()).rev().enumerate() {
194                 shift_arr_right(&mut packet_data);
195                 packet_data[0..33].copy_from_slice(&payload.encode()[..]);
196                 packet_data[33..65].copy_from_slice(&hmac_res);
197
198                 let mut chacha = ChaCha20::new(&keys.rho, &[0u8; 8]);
199                 chacha.process(&packet_data, &mut buf[0..20*65]);
200                 packet_data[..].copy_from_slice(&buf[0..20*65]);
201
202                 if i == 0 {
203                         packet_data[20*65 - filler.len()..20*65].copy_from_slice(&filler[..]);
204                 }
205
206                 let mut hmac = HmacEngine::<Sha256>::new(&keys.mu);
207                 hmac.input(&packet_data);
208                 hmac.input(&associated_data.0[..]);
209                 hmac_res = Hmac::from_engine(hmac).into_inner();
210         }
211
212         msgs::OnionPacket{
213                 version: 0,
214                 public_key: Ok(onion_keys.first().unwrap().ephemeral_pubkey),
215                 hop_data: packet_data,
216                 hmac: hmac_res,
217         }
218 }
219
220 /// Encrypts a failure packet. raw_packet can either be a
221 /// msgs::DecodedOnionErrorPacket.encode() result or a msgs::OnionErrorPacket.data element.
222 pub(super) fn encrypt_failure_packet(shared_secret: &[u8], raw_packet: &[u8]) -> msgs::OnionErrorPacket {
223         let ammag = gen_ammag_from_shared_secret(&shared_secret);
224
225         let mut packet_crypted = Vec::with_capacity(raw_packet.len());
226         packet_crypted.resize(raw_packet.len(), 0);
227         let mut chacha = ChaCha20::new(&ammag, &[0u8; 8]);
228         chacha.process(&raw_packet, &mut packet_crypted[..]);
229         msgs::OnionErrorPacket {
230                 data: packet_crypted,
231         }
232 }
233
234 pub(super) fn build_failure_packet(shared_secret: &[u8], failure_type: u16, failure_data: &[u8]) -> msgs::DecodedOnionErrorPacket {
235         assert_eq!(shared_secret.len(), 32);
236         assert!(failure_data.len() <= 256 - 2);
237
238         let um = gen_um_from_shared_secret(&shared_secret);
239
240         let failuremsg = {
241                 let mut res = Vec::with_capacity(2 + failure_data.len());
242                 res.push(((failure_type >> 8) & 0xff) as u8);
243                 res.push(((failure_type >> 0) & 0xff) as u8);
244                 res.extend_from_slice(&failure_data[..]);
245                 res
246         };
247         let pad = {
248                 let mut res = Vec::with_capacity(256 - 2 - failure_data.len());
249                 res.resize(256 - 2 - failure_data.len(), 0);
250                 res
251         };
252         let mut packet = msgs::DecodedOnionErrorPacket {
253                 hmac: [0; 32],
254                 failuremsg: failuremsg,
255                 pad: pad,
256         };
257
258         let mut hmac = HmacEngine::<Sha256>::new(&um);
259         hmac.input(&packet.encode()[32..]);
260         packet.hmac = Hmac::from_engine(hmac).into_inner();
261
262         packet
263 }
264
265 #[inline]
266 pub(super) fn build_first_hop_failure_packet(shared_secret: &[u8], failure_type: u16, failure_data: &[u8]) -> msgs::OnionErrorPacket {
267         let failure_packet = build_failure_packet(shared_secret, failure_type, failure_data);
268         encrypt_failure_packet(shared_secret, &failure_packet.encode()[..])
269 }
270
271 /// Process failure we got back from upstream on a payment we sent (implying htlc_source is an
272 /// OutboundRoute).
273 /// Returns update, a boolean indicating that the payment itself failed, and the error code.
274 pub(super) fn process_onion_failure<T: secp256k1::Signing>(secp_ctx: &Secp256k1<T>, logger: &Arc<Logger>, htlc_source: &HTLCSource, mut packet_decrypted: Vec<u8>) -> (Option<msgs::HTLCFailChannelUpdate>, bool, Option<u16>) {
275         if let &HTLCSource::OutboundRoute { ref route, ref session_priv, ref first_hop_htlc_msat } = htlc_source {
276                 let mut res = None;
277                 let mut htlc_msat = *first_hop_htlc_msat;
278                 let mut error_code_ret = None;
279                 let mut next_route_hop_ix = 0;
280                 let mut is_from_final_node = false;
281
282                 // Handle packed channel/node updates for passing back for the route handler
283                 construct_onion_keys_callback(secp_ctx, route, session_priv, |shared_secret, _, _, route_hop| {
284                         next_route_hop_ix += 1;
285                         if res.is_some() { return; }
286
287                         let amt_to_forward = htlc_msat - route_hop.fee_msat;
288                         htlc_msat = amt_to_forward;
289
290                         let ammag = gen_ammag_from_shared_secret(&shared_secret[..]);
291
292                         let mut decryption_tmp = Vec::with_capacity(packet_decrypted.len());
293                         decryption_tmp.resize(packet_decrypted.len(), 0);
294                         let mut chacha = ChaCha20::new(&ammag, &[0u8; 8]);
295                         chacha.process(&packet_decrypted, &mut decryption_tmp[..]);
296                         packet_decrypted = decryption_tmp;
297
298                         is_from_final_node = route.hops.last().unwrap().pubkey == route_hop.pubkey;
299
300                         if let Ok(err_packet) = msgs::DecodedOnionErrorPacket::read(&mut Cursor::new(&packet_decrypted)) {
301                                 let um = gen_um_from_shared_secret(&shared_secret[..]);
302                                 let mut hmac = HmacEngine::<Sha256>::new(&um);
303                                 hmac.input(&err_packet.encode()[32..]);
304
305                                 if fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &err_packet.hmac) {
306                                         if let Some(error_code_slice) = err_packet.failuremsg.get(0..2) {
307                                                 const PERM: u16 = 0x4000;
308                                                 const NODE: u16 = 0x2000;
309                                                 const UPDATE: u16 = 0x1000;
310
311                                                 let error_code = byte_utils::slice_to_be16(&error_code_slice);
312                                                 error_code_ret = Some(error_code);
313
314                                                 let (debug_field, debug_field_size) = errors::get_onion_debug_field(error_code);
315
316                                                 // indicate that payment parameter has failed and no need to
317                                                 // update Route object
318                                                 let payment_failed = (match error_code & 0xff {
319                                                         15|16|17|18|19 => true,
320                                                         _ => false,
321                                                 } && is_from_final_node) // PERM bit observed below even this error is from the intermediate nodes
322                                                 || error_code == 21; // Special case error 21 as the Route object is bogus, TODO: Maybe fail the node if the CLTV was reasonable?
323
324                                                 let mut fail_channel_update = None;
325
326                                                 if error_code & NODE == NODE {
327                                                         fail_channel_update = Some(msgs::HTLCFailChannelUpdate::NodeFailure { node_id: route_hop.pubkey, is_permanent: error_code & PERM == PERM });
328                                                 }
329                                                 else if error_code & PERM == PERM {
330                                                         fail_channel_update = if payment_failed {None} else {Some(msgs::HTLCFailChannelUpdate::ChannelClosed {
331                                                                 short_channel_id: route.hops[next_route_hop_ix - if next_route_hop_ix == route.hops.len() { 1 } else { 0 }].short_channel_id,
332                                                                 is_permanent: true,
333                                                         })};
334                                                 }
335                                                 else if error_code & UPDATE == UPDATE {
336                                                         if let Some(update_len_slice) = err_packet.failuremsg.get(debug_field_size+2..debug_field_size+4) {
337                                                                 let update_len = byte_utils::slice_to_be16(&update_len_slice) as usize;
338                                                                 if let Some(update_slice) = err_packet.failuremsg.get(debug_field_size + 4..debug_field_size + 4 + update_len) {
339                                                                         if let Ok(chan_update) = msgs::ChannelUpdate::read(&mut Cursor::new(&update_slice)) {
340                                                                                 // if channel_update should NOT have caused the failure:
341                                                                                 // MAY treat the channel_update as invalid.
342                                                                                 let is_chan_update_invalid = match error_code & 0xff {
343                                                                                         7 => false,
344                                                                                         11 => amt_to_forward > chan_update.contents.htlc_minimum_msat,
345                                                                                         12 => {
346                                                                                                 let new_fee = amt_to_forward.checked_mul(chan_update.contents.fee_proportional_millionths as u64).and_then(|prop_fee| { (prop_fee / 1000000).checked_add(chan_update.contents.fee_base_msat as u64) });
347                                                                                                 new_fee.is_some() && route_hop.fee_msat >= new_fee.unwrap()
348                                                                                         }
349                                                                                         13 => route_hop.cltv_expiry_delta as u16 >= chan_update.contents.cltv_expiry_delta,
350                                                                                         14 => false, // expiry_too_soon; always valid?
351                                                                                         20 => chan_update.contents.flags & 2 == 0,
352                                                                                         _ => false, // unknown error code; take channel_update as valid
353                                                                                 };
354                                                                                 fail_channel_update = if is_chan_update_invalid {
355                                                                                         // This probably indicates the node which forwarded
356                                                                                         // to the node in question corrupted something.
357                                                                                         Some(msgs::HTLCFailChannelUpdate::ChannelClosed {
358                                                                                                 short_channel_id: route_hop.short_channel_id,
359                                                                                                 is_permanent: true,
360                                                                                         })
361                                                                                 } else {
362                                                                                         Some(msgs::HTLCFailChannelUpdate::ChannelUpdateMessage {
363                                                                                                 msg: chan_update,
364                                                                                         })
365                                                                                 };
366                                                                         }
367                                                                 }
368                                                         }
369                                                         if fail_channel_update.is_none() {
370                                                                 // They provided an UPDATE which was obviously bogus, not worth
371                                                                 // trying to relay through them anymore.
372                                                                 fail_channel_update = Some(msgs::HTLCFailChannelUpdate::NodeFailure {
373                                                                         node_id: route_hop.pubkey,
374                                                                         is_permanent: true,
375                                                                 });
376                                                         }
377                                                 } else if !payment_failed {
378                                                         // We can't understand their error messages and they failed to
379                                                         // forward...they probably can't understand our forwards so its
380                                                         // really not worth trying any further.
381                                                         fail_channel_update = Some(msgs::HTLCFailChannelUpdate::NodeFailure {
382                                                                 node_id: route_hop.pubkey,
383                                                                 is_permanent: true,
384                                                         });
385                                                 }
386
387                                                 // TODO: Here (and a few other places) we assume that BADONION errors
388                                                 // are always "sourced" from the node previous to the one which failed
389                                                 // to decode the onion.
390                                                 res = Some((fail_channel_update, !(error_code & PERM == PERM && is_from_final_node)));
391
392                                                 let (description, title) = errors::get_onion_error_description(error_code);
393                                                 if debug_field_size > 0 && err_packet.failuremsg.len() >= 4 + debug_field_size {
394                                                         let log_holder = LogHolder { logger };
395                                                         log_warn!(log_holder, "Onion Error[{}({:#x}) {}({})] {}", title, error_code, debug_field, log_bytes!(&err_packet.failuremsg[4..4+debug_field_size]), description);
396                                                 }
397                                                 else {
398                                                         let log_holder = LogHolder { logger };
399                                                         log_warn!(log_holder, "Onion Error[{}({:#x})] {}", title, error_code, description);
400                                                 }
401                                         } else {
402                                                 // Useless packet that we can't use but it passed HMAC, so it
403                                                 // definitely came from the peer in question
404                                                 res = Some((Some(msgs::HTLCFailChannelUpdate::NodeFailure {
405                                                         node_id: route_hop.pubkey,
406                                                         is_permanent: true,
407                                                 }), !is_from_final_node));
408                                         }
409                                 }
410                         }
411                 }).expect("Route that we sent via spontaneously grew invalid keys in the middle of it?");
412                 if let Some((channel_update, payment_retryable)) = res {
413                         (channel_update, payment_retryable, error_code_ret)
414                 } else {
415                         // only not set either packet unparseable or hmac does not match with any
416                         // payment not retryable only when garbage is from the final node
417                         (None, !is_from_final_node, None)
418                 }
419         } else { unreachable!(); }
420 }
421
422 #[cfg(test)]
423 mod tests {
424         use ln::channelmanager::PaymentHash;
425         use ln::features::{ChannelFeatures, NodeFeatures};
426         use ln::router::{Route, RouteHop};
427         use ln::msgs;
428         use util::ser::Writeable;
429
430         use hex;
431
432         use secp256k1::Secp256k1;
433         use secp256k1::key::{PublicKey,SecretKey};
434
435         use super::OnionKeys;
436
437         fn build_test_onion_keys() -> Vec<OnionKeys> {
438                 // Keys from BOLT 4, used in both test vector tests
439                 let secp_ctx = Secp256k1::new();
440
441                 let route = Route {
442                         hops: vec!(
443                                         RouteHop {
444                                                 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
445                                                 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
446                                                 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
447                                         },
448                                         RouteHop {
449                                                 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
450                                                 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
451                                                 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
452                                         },
453                                         RouteHop {
454                                                 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
455                                                 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
456                                                 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
457                                         },
458                                         RouteHop {
459                                                 pubkey: PublicKey::from_slice(&hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]).unwrap(),
460                                                 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
461                                                 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
462                                         },
463                                         RouteHop {
464                                                 pubkey: PublicKey::from_slice(&hex::decode("02edabbd16b41c8371b92ef2f04c1185b4f03b6dcd52ba9b78d9d7c89c8f221145").unwrap()[..]).unwrap(),
465                                                 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
466                                                 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
467                                         },
468                         ),
469                 };
470
471                 let session_priv = SecretKey::from_slice(&hex::decode("4141414141414141414141414141414141414141414141414141414141414141").unwrap()[..]).unwrap();
472
473                 let onion_keys = super::construct_onion_keys(&secp_ctx, &route, &session_priv).unwrap();
474                 assert_eq!(onion_keys.len(), route.hops.len());
475                 onion_keys
476         }
477
478         #[test]
479         fn onion_vectors() {
480                 // Packet creation test vectors from BOLT 4
481                 let onion_keys = build_test_onion_keys();
482
483                 assert_eq!(onion_keys[0].shared_secret[..], hex::decode("53eb63ea8a3fec3b3cd433b85cd62a4b145e1dda09391b348c4e1cd36a03ea66").unwrap()[..]);
484                 assert_eq!(onion_keys[0].blinding_factor[..], hex::decode("2ec2e5da605776054187180343287683aa6a51b4b1c04d6dd49c45d8cffb3c36").unwrap()[..]);
485                 assert_eq!(onion_keys[0].ephemeral_pubkey.serialize()[..], hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]);
486                 assert_eq!(onion_keys[0].rho, hex::decode("ce496ec94def95aadd4bec15cdb41a740c9f2b62347c4917325fcc6fb0453986").unwrap()[..]);
487                 assert_eq!(onion_keys[0].mu, hex::decode("b57061dc6d0a2b9f261ac410c8b26d64ac5506cbba30267a649c28c179400eba").unwrap()[..]);
488
489                 assert_eq!(onion_keys[1].shared_secret[..], hex::decode("a6519e98832a0b179f62123b3567c106db99ee37bef036e783263602f3488fae").unwrap()[..]);
490                 assert_eq!(onion_keys[1].blinding_factor[..], hex::decode("bf66c28bc22e598cfd574a1931a2bafbca09163df2261e6d0056b2610dab938f").unwrap()[..]);
491                 assert_eq!(onion_keys[1].ephemeral_pubkey.serialize()[..], hex::decode("028f9438bfbf7feac2e108d677e3a82da596be706cc1cf342b75c7b7e22bf4e6e2").unwrap()[..]);
492                 assert_eq!(onion_keys[1].rho, hex::decode("450ffcabc6449094918ebe13d4f03e433d20a3d28a768203337bc40b6e4b2c59").unwrap()[..]);
493                 assert_eq!(onion_keys[1].mu, hex::decode("05ed2b4a3fb023c2ff5dd6ed4b9b6ea7383f5cfe9d59c11d121ec2c81ca2eea9").unwrap()[..]);
494
495                 assert_eq!(onion_keys[2].shared_secret[..], hex::decode("3a6b412548762f0dbccce5c7ae7bb8147d1caf9b5471c34120b30bc9c04891cc").unwrap()[..]);
496                 assert_eq!(onion_keys[2].blinding_factor[..], hex::decode("a1f2dadd184eb1627049673f18c6325814384facdee5bfd935d9cb031a1698a5").unwrap()[..]);
497                 assert_eq!(onion_keys[2].ephemeral_pubkey.serialize()[..], hex::decode("03bfd8225241ea71cd0843db7709f4c222f62ff2d4516fd38b39914ab6b83e0da0").unwrap()[..]);
498                 assert_eq!(onion_keys[2].rho, hex::decode("11bf5c4f960239cb37833936aa3d02cea82c0f39fd35f566109c41f9eac8deea").unwrap()[..]);
499                 assert_eq!(onion_keys[2].mu, hex::decode("caafe2820fa00eb2eeb78695ae452eba38f5a53ed6d53518c5c6edf76f3f5b78").unwrap()[..]);
500
501                 assert_eq!(onion_keys[3].shared_secret[..], hex::decode("21e13c2d7cfe7e18836df50872466117a295783ab8aab0e7ecc8c725503ad02d").unwrap()[..]);
502                 assert_eq!(onion_keys[3].blinding_factor[..], hex::decode("7cfe0b699f35525029ae0fa437c69d0f20f7ed4e3916133f9cacbb13c82ff262").unwrap()[..]);
503                 assert_eq!(onion_keys[3].ephemeral_pubkey.serialize()[..], hex::decode("031dde6926381289671300239ea8e57ffaf9bebd05b9a5b95beaf07af05cd43595").unwrap()[..]);
504                 assert_eq!(onion_keys[3].rho, hex::decode("cbe784ab745c13ff5cffc2fbe3e84424aa0fd669b8ead4ee562901a4a4e89e9e").unwrap()[..]);
505                 assert_eq!(onion_keys[3].mu, hex::decode("5052aa1b3d9f0655a0932e50d42f0c9ba0705142c25d225515c45f47c0036ee9").unwrap()[..]);
506
507                 assert_eq!(onion_keys[4].shared_secret[..], hex::decode("b5756b9b542727dbafc6765a49488b023a725d631af688fc031217e90770c328").unwrap()[..]);
508                 assert_eq!(onion_keys[4].blinding_factor[..], hex::decode("c96e00dddaf57e7edcd4fb5954be5b65b09f17cb6d20651b4e90315be5779205").unwrap()[..]);
509                 assert_eq!(onion_keys[4].ephemeral_pubkey.serialize()[..], hex::decode("03a214ebd875aab6ddfd77f22c5e7311d7f77f17a169e599f157bbcdae8bf071f4").unwrap()[..]);
510                 assert_eq!(onion_keys[4].rho, hex::decode("034e18b8cc718e8af6339106e706c52d8df89e2b1f7e9142d996acf88df8799b").unwrap()[..]);
511                 assert_eq!(onion_keys[4].mu, hex::decode("8e45e5c61c2b24cb6382444db6698727afb063adecd72aada233d4bf273d975a").unwrap()[..]);
512
513                 // Test vectors below are flat-out wrong: they claim to set outgoing_cltv_value to non-0 :/
514                 let payloads = vec!(
515                         msgs::OnionHopData {
516                                 format: msgs::OnionHopDataFormat::Legacy,
517                                 short_channel_id: 0,
518                                 amt_to_forward: 0,
519                                 outgoing_cltv_value: 0,
520                         },
521                         msgs::OnionHopData {
522                                 format: msgs::OnionHopDataFormat::Legacy,
523                                 short_channel_id: 0x0101010101010101,
524                                 amt_to_forward: 0x0100000001,
525                                 outgoing_cltv_value: 0,
526                         },
527                         msgs::OnionHopData {
528                                 format: msgs::OnionHopDataFormat::Legacy,
529                                 short_channel_id: 0x0202020202020202,
530                                 amt_to_forward: 0x0200000002,
531                                 outgoing_cltv_value: 0,
532                         },
533                         msgs::OnionHopData {
534                                 format: msgs::OnionHopDataFormat::Legacy,
535                                 short_channel_id: 0x0303030303030303,
536                                 amt_to_forward: 0x0300000003,
537                                 outgoing_cltv_value: 0,
538                         },
539                         msgs::OnionHopData {
540                                 format: msgs::OnionHopDataFormat::Legacy,
541                                 short_channel_id: 0x0404040404040404,
542                                 amt_to_forward: 0x0400000004,
543                                 outgoing_cltv_value: 0,
544                         },
545                 );
546
547                 let packet = [0; 20*65];
548                 let packet = super::construct_onion_packet_with_init_noise(payloads, onion_keys, packet, &PaymentHash([0x42; 32]));
549                 // Just check the final packet encoding, as it includes all the per-hop vectors in it
550                 // anyway...
551                 assert_eq!(packet.encode(), hex::decode("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").unwrap());
552         }
553
554         #[test]
555         fn test_failure_packet_onion() {
556                 // Returning Errors test vectors from BOLT 4
557
558                 let onion_keys = build_test_onion_keys();
559                 let onion_error = super::build_failure_packet(&onion_keys[4].shared_secret[..], 0x2002, &[0; 0]);
560                 assert_eq!(onion_error.encode(), hex::decode("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").unwrap());
561
562                 let onion_packet_1 = super::encrypt_failure_packet(&onion_keys[4].shared_secret[..], &onion_error.encode()[..]);
563                 assert_eq!(onion_packet_1.data, hex::decode("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").unwrap());
564
565                 let onion_packet_2 = super::encrypt_failure_packet(&onion_keys[3].shared_secret[..], &onion_packet_1.data[..]);
566                 assert_eq!(onion_packet_2.data, hex::decode("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").unwrap());
567
568                 let onion_packet_3 = super::encrypt_failure_packet(&onion_keys[2].shared_secret[..], &onion_packet_2.data[..]);
569                 assert_eq!(onion_packet_3.data, hex::decode("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").unwrap());
570
571                 let onion_packet_4 = super::encrypt_failure_packet(&onion_keys[1].shared_secret[..], &onion_packet_3.data[..]);
572                 assert_eq!(onion_packet_4.data, hex::decode("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").unwrap());
573
574                 let onion_packet_5 = super::encrypt_failure_packet(&onion_keys[0].shared_secret[..], &onion_packet_4.data[..]);
575                 assert_eq!(onion_packet_5.data, hex::decode("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").unwrap());
576         }
577 }