In case of an unilateral close from the remote side while we suffered a * loss of data, this tries to recover the private key from the `to_remote` * output. * This basically iterates over every `dbid` to derive the channel_seed and * then derives the payment basepoint to compare to the pubkey hash specified * in the witness programm. * Note that since a node generates the key for the to_remo
| 358 | * :param passwd: The *optional* hsm_secret password |
| 359 | */ |
| 360 | static int guess_to_remote(const char *address, struct node_id *node_id, |
| 361 | u64 tries, char *hsm_secret_path) |
| 362 | { |
| 363 | struct secret hsm_secret, channel_seed, basepoint_secret; |
| 364 | char *passwd, *err; |
| 365 | struct pubkey basepoint; |
| 366 | struct ripemd160 pubkeyhash; |
| 367 | /* We only support P2WPKH, hence 20. */ |
| 368 | u8 goal_pubkeyhash[20]; |
| 369 | /* See common/bech32.h for buffer size. */ |
| 370 | char hrp[strlen(address) - 6]; |
| 371 | int witver, exit_code = 0; |
| 372 | size_t witlen; |
| 373 | |
| 374 | /* Get the hrp to accept addresses from any network. */ |
| 375 | if (bech32_decode(hrp, goal_pubkeyhash, &witlen, address, 90) != BECH32_ENCODING_BECH32) |
| 376 | errx(ERROR_USAGE, "Could not get address' network"); |
| 377 | if (segwit_addr_decode(&witver, goal_pubkeyhash, &witlen, hrp, address) != 1) |
| 378 | errx(ERROR_USAGE, "Wrong bech32 address"); |
| 379 | |
| 380 | secp256k1_ctx = secp256k1_context_create(SECP256K1_CONTEXT_VERIFY |
| 381 | | SECP256K1_CONTEXT_SIGN); |
| 382 | |
| 383 | /* This checks the file existence, too. */ |
| 384 | if (hsm_secret_is_encrypted(hsm_secret_path)) { |
| 385 | printf("Enter hsm_secret password:\n"); |
| 386 | fflush(stdout); |
| 387 | passwd = read_stdin_pass_with_exit_code(&err, &exit_code); |
| 388 | if (!passwd) |
| 389 | errx(exit_code, "%s", err); |
| 390 | get_encrypted_hsm_secret(&hsm_secret, hsm_secret_path, passwd); |
| 391 | free(passwd); |
| 392 | } else |
| 393 | get_hsm_secret(&hsm_secret, hsm_secret_path); |
| 394 | |
| 395 | for (u64 dbid = 1; dbid < tries ; dbid++) { |
| 396 | get_channel_seed(&channel_seed, node_id, dbid, &hsm_secret); |
| 397 | if (!derive_payment_basepoint(&channel_seed, |
| 398 | &basepoint, &basepoint_secret)) |
| 399 | errx(ERROR_KEYDERIV, "Could not derive basepoints for dbid %"PRIu64 |
| 400 | " and channel seed %s.", dbid, |
| 401 | type_to_string(tmpctx, |
| 402 | struct secret, &channel_seed)); |
| 403 | |
| 404 | pubkey_to_hash160(&basepoint, &pubkeyhash); |
| 405 | if (memcmp(pubkeyhash.u.u8, goal_pubkeyhash, 20) == 0) { |
| 406 | printf("bech32 : %s\n", address); |
| 407 | printf("pubkey hash : %s\n", |
| 408 | tal_hexstr(tmpctx, pubkeyhash.u.u8, 20)); |
| 409 | printf("pubkey : %s \n", |
| 410 | type_to_string(tmpctx, struct pubkey, &basepoint)); |
| 411 | printf("privkey : %s \n", |
| 412 | type_to_string(tmpctx, struct secret, &basepoint_secret)); |
| 413 | return 0; |
| 414 | } |
| 415 | } |
| 416 | |
| 417 | printf("Could not find any basepoint matching the provided witness programm.\n" |
no test coverage detected