~ This is another lightningd-only interface; signing a commit transaction. * This is dangerous, since if we sign a revoked commitment tx we'll lose * funds, thus it's only available to lightningd. * * * Oh look, another FIXME! */ FIXME: Ensure HSM never does this twice for same dbid! */
| 1315 | * Oh look, another FIXME! */ |
| 1316 | /* FIXME: Ensure HSM never does this twice for same dbid! */ |
| 1317 | static u8 *handle_sign_commitment_tx(struct hsmd_client *c, const u8 *msg_in) |
| 1318 | { |
| 1319 | struct pubkey remote_funding_pubkey, local_funding_pubkey; |
| 1320 | struct node_id peer_id; |
| 1321 | u64 dbid; |
| 1322 | struct secret channel_seed; |
| 1323 | struct bitcoin_tx *tx; |
| 1324 | struct bitcoin_signature sig; |
| 1325 | u64 commit_num; |
| 1326 | struct secrets secrets; |
| 1327 | const u8 *funding_wscript; |
| 1328 | |
| 1329 | if (!fromwire_hsmd_sign_commitment_tx(tmpctx, msg_in, |
| 1330 | &peer_id, &dbid, |
| 1331 | &tx, |
| 1332 | &remote_funding_pubkey, |
| 1333 | &commit_num)) |
| 1334 | return hsmd_status_malformed_request(c, msg_in); |
| 1335 | |
| 1336 | tx->chainparams = c->chainparams; |
| 1337 | |
| 1338 | /* Basic sanity checks. */ |
| 1339 | if (tx->wtx->num_inputs != 1) |
| 1340 | return hsmd_status_bad_request(c, msg_in, |
| 1341 | "tx must have 1 input"); |
| 1342 | |
| 1343 | if (tx->wtx->num_outputs == 0) |
| 1344 | return hsmd_status_bad_request_fmt(c, msg_in, |
| 1345 | "tx must have > 0 outputs"); |
| 1346 | |
| 1347 | get_channel_seed(&peer_id, dbid, &channel_seed); |
| 1348 | derive_basepoints(&channel_seed, |
| 1349 | &local_funding_pubkey, NULL, &secrets, NULL); |
| 1350 | |
| 1351 | /*~ Bitcoin signatures cover the (part of) the script they're |
| 1352 | * executing; the rules are a bit complex in general, but for |
| 1353 | * Segregated Witness it's simply the current script. */ |
| 1354 | funding_wscript = bitcoin_redeem_2of2(tmpctx, |
| 1355 | &local_funding_pubkey, |
| 1356 | &remote_funding_pubkey); |
| 1357 | sign_tx_input(tx, 0, NULL, funding_wscript, |
| 1358 | &secrets.funding_privkey, |
| 1359 | &local_funding_pubkey, |
| 1360 | SIGHASH_ALL, |
| 1361 | &sig); |
| 1362 | |
| 1363 | return towire_hsmd_sign_commitment_tx_reply(NULL, &sig); |
| 1364 | } |
| 1365 | |
| 1366 | /* ~This stub implementation is overriden by fully validating signers |
| 1367 | * that need to independently verify the peer's signatures. */ |
no test coverage detected