/* * Copyright 2012-2016 Luke Dashjr * * This program is free software; you can redistribute it and/or modify it * under the terms of the standard MIT license. See COPYING for more details. */ #include #include #include #include #include #include #include #ifndef WIN32 #include #else #include #endif #include #include #include "private.h" const char *blkmk_supported_rules[] = { "csv", NULL }; bool blkmk_supports_rule(const char * const rulename) { for (const char **r = blkmk_supported_rules; *r; ++r) { if (!strcmp(rulename, *r)) { return true; } } return false; } static inline void my_htole32(unsigned char *buf, uint32_t n) { buf[0] = (n >> 0) % 256; buf[1] = (n >> 8) % 256; buf[2] = (n >> 16) % 256; buf[3] = (n >> 24) % 256; } static inline void my_htole64(unsigned char *buf, uint64_t n) { for (int i = 0; i < 8; ++i) buf[i] = (n >> (8*i)) & 0xff; } bool (*blkmk_sha256_impl)(void *, const void *, size_t) = NULL; bool _blkmk_dblsha256(void *hash, const void *data, size_t datasz) { return blkmk_sha256_impl(hash, data, datasz) && blkmk_sha256_impl(hash, hash, 32); } #define dblsha256 _blkmk_dblsha256 #define max_varint_size (9) static char varintEncode(unsigned char *out, uint64_t n) { if (n < 0xfd) { out[0] = n; return 1; } char L; if (n <= 0xffff) { out[0] = '\xfd'; L = 3; } else if (n <= 0xffffffff) { out[0] = '\xfe'; L = 5; } else { out[0] = '\xff'; L = 9; } for (unsigned char i = 1; i < L; ++i) out[i] = (n >> ((i - 1) * 8)) % 256; return L; } static uint8_t blkmk_varint_encode_size(const uint64_t n) { uint8_t dummy[max_varint_size]; return varintEncode(dummy, n); } static int16_t blkmk_count_sigops(const uint8_t * const script, const size_t scriptsz) { int16_t sigops = 0; for (size_t i = 0; i < scriptsz; ++i) { if (script[i] <= 0x4c /* OP_PUSHDATA1 */) { if (script[i] == 0x4c) { if (i + 1 >= scriptsz) { break; } ++i; } i += script[i]; } else if (script[i] == 0x4d /* OP_PUSHDATA2 */) { if (i + 2 >= scriptsz) { break; } i += 2 + upk_u16le(script, i + 1); } else if (script[i] == 0x4e /* OP_PUSHDATA4 */) { if (i + 4 >= scriptsz) { break; } i += 4 + upk_u32le(script, i + 1); } else if (script[i] == 0xac /* OP_CHECKSIG */ || script[i] == 0xad /* OP_CHECKSIGVERIFY */) { ++sigops; } else if (script[i] == 0xae /* OP_CHECKMULTISIG */ || script[i] == 0xaf /* OP_CHECKMULTISIGVERIFY */) { sigops += 20; } } return sigops; } uint64_t blkmk_init_generation3(blktemplate_t * const tmpl, const void * const script, const size_t scriptsz, bool * const inout_newcb) { if (tmpl->cbtxn && !(*inout_newcb && (tmpl->mutations & BMM_GENERATE))) { *inout_newcb = false; return 0; } if (!tmpl->cbvalue) { // TODO: Figure it out from the existing cbtxn *inout_newcb = false; return 0; } *inout_newcb = true; if (scriptsz >= 0xfd) return 0; unsigned char *data = malloc(168 + scriptsz); size_t off = 0; if (!data) return 0; memcpy(&data[0], "\x01\0\0\0" // txn ver "\x01" // input count "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" // prevout "\xff\xff\xff\xff" // index (-1) "\x02" // scriptSig length // height serialization length (set later) , 42); off += 43; blkheight_t h = tmpl->height; while (h > 127) { ++data[41]; data[off++] = h & 0xff; h >>= 8; } data[off++] = h; data[42] = data[41] - 1; if (tmpl->aux_count) { unsigned auxsz = off++; data[auxsz] = 0; ++data[41]; for (unsigned i = 0; i < tmpl->aux_count; ++i) { struct blkaux_t * const aux = &tmpl->auxs[i]; if ((size_t)data[41] + aux->datasz > libblkmaker_coinbase_size_limit) { free(data); return 0; } memcpy(&data[off], tmpl->auxs[i].data, aux->datasz); data[41] += aux->datasz; data[auxsz] += aux->datasz; off += aux->datasz; } } memcpy(&data[off], "\xff\xff\xff\xff" // sequence "\x01" // output count , 5); off += 5; my_htole64(&data[off], tmpl->cbvalue); off += 8; data[off++] = scriptsz; memcpy(&data[off], script, scriptsz); off += scriptsz; memset(&data[off], 0, 4); // lock time off += 4; const unsigned long pretx_size = libblkmaker_blkheader_size + blkmk_varint_encode_size(1 + tmpl->txncount); const int16_t sigops_counted = blkmk_count_sigops(script, scriptsz); if (pretx_size + tmpl->txns_datasz + off > tmpl->sizelimit || (tmpl->txns_sigops >= 0 && tmpl->txns_sigops + sigops_counted > tmpl->sigoplimit)) { free(data); return 0; } struct blktxn_t *txn = malloc(sizeof(*tmpl->cbtxn)); if (!txn) { free(data); return 0; } blktxn_init(txn); txn->data = data; txn->datasz = off; txn->sigops_ = sigops_counted; if (tmpl->cbtxn) { blktxn_clean(tmpl->cbtxn); free(tmpl->cbtxn); } tmpl->cbtxn = txn; tmpl->mutations |= BMM_CBAPPEND | BMM_CBSET | BMM_GENERATE; return tmpl->cbvalue; } uint64_t blkmk_init_generation2(blktemplate_t *tmpl, void *script, size_t scriptsz, bool *out_newcb) { bool tmp; if (!out_newcb) out_newcb = &tmp; *out_newcb = false; return blkmk_init_generation3(tmpl, script, scriptsz, out_newcb); } uint64_t blkmk_init_generation(blktemplate_t *tmpl, void *script, size_t scriptsz) { return blkmk_init_generation2(tmpl, script, scriptsz, NULL); } static bool blkmk_hash_transactions(blktemplate_t * const tmpl) { for (unsigned long i = 0; i < tmpl->txncount; ++i) { struct blktxn_t * const txn = &tmpl->txns[i]; if (txn->hash_) continue; txn->hash_ = malloc(sizeof(*txn->hash_)); if (!dblsha256(txn->hash_, txn->data, txn->datasz)) { free(txn->hash_); return false; } } return true; } static bool blkmk_build_merkle_branches(blktemplate_t * const tmpl) { int branchcount, i; libblkmaker_hash_t *branches; if (tmpl->_mrklbranch) return true; if (!blkmk_hash_transactions(tmpl)) return false; branchcount = blkmk_flsl(tmpl->txncount); if (!branchcount) { tmpl->_mrklbranchcount = 0; tmpl->_mrklbranch = NULL; return true; } branches = malloc(branchcount * sizeof(*branches)); if (!branches) { return false; } size_t hashcount = tmpl->txncount + 1; libblkmaker_hash_t * const hashes = malloc((hashcount + 1) * sizeof(*hashes)); // +1 for when the last needs duplicating if (!hashes) { free(branches); return false; } for (i = 0; i < tmpl->txncount; ++i) { memcpy(&hashes[i + 1], tmpl->txns[i].hash_, sizeof(*hashes)); } for (i = 0; i < branchcount; ++i) { memcpy(&branches[i], &hashes[1], sizeof(*hashes)); if (hashcount % 2) { memcpy(&hashes[hashcount], &hashes[hashcount - 1], sizeof(*hashes)); ++hashcount; } for (size_t i = 2; i < hashcount; i += 2) // This is where we overlap input and output, on the first pair if (!dblsha256(&hashes[i / 2], &hashes[i], sizeof(*hashes) * 2)) { free(branches); free(hashes); return false; } hashcount /= 2; } free(hashes); tmpl->_mrklbranch = branches; tmpl->_mrklbranchcount = branchcount; return true; } static bool build_merkle_root(unsigned char *mrklroot_out, blktemplate_t *tmpl, unsigned char *cbtxndata, size_t cbtxndatasz) { int i; libblkmaker_hash_t hashes[0x40]; if (!blkmk_build_merkle_branches(tmpl)) return false; if (!dblsha256(&hashes[0], cbtxndata, cbtxndatasz)) return false; for (i = 0; i < tmpl->_mrklbranchcount; ++i) { memcpy(&hashes[1], tmpl->_mrklbranch[i], 0x20); // This is where we overlap input and output, on the first pair if (!dblsha256(&hashes[0], &hashes[0], 0x40)) return false; } memcpy(mrklroot_out, &hashes[0], 32); return true; } static const int cbScriptSigLen = 4 + 1 + 36; static bool _blkmk_append_cb(blktemplate_t * const tmpl, void * const vout, const void * const append, const size_t appendsz, size_t * const appended_at_offset, int16_t * const sigops_counted_p) { unsigned char *out = vout; unsigned char *in = tmpl->cbtxn->data; size_t insz = tmpl->cbtxn->datasz; if (appendsz > libblkmaker_coinbase_size_limit || in[cbScriptSigLen] > libblkmaker_coinbase_size_limit - appendsz) { return false; } const unsigned long pretx_size = libblkmaker_blkheader_size + blkmk_varint_encode_size(1 + tmpl->txncount); if (pretx_size + tmpl->cbtxn->datasz + tmpl->txns_datasz + appendsz > tmpl->sizelimit) { return false; } const int16_t orig_scriptSig_sigops = blkmk_count_sigops(&in[cbScriptSigLen + 1], in[cbScriptSigLen]); int cbPostScriptSig = cbScriptSigLen + 1 + in[cbScriptSigLen]; if (appended_at_offset) *appended_at_offset = cbPostScriptSig; unsigned char *outPostScriptSig = &out[cbPostScriptSig]; void *outExtranonce = (void*)outPostScriptSig; outPostScriptSig += appendsz; if (out != in) { memcpy(out, in, cbPostScriptSig+1); memcpy(outPostScriptSig, &in[cbPostScriptSig], insz - cbPostScriptSig); } else memmove(outPostScriptSig, &in[cbPostScriptSig], insz - cbPostScriptSig); out[cbScriptSigLen] += appendsz; memcpy(outExtranonce, append, appendsz); const int16_t sigops_counted = tmpl->cbtxn->sigops_ + blkmk_count_sigops(&out[cbScriptSigLen + 1], out[cbScriptSigLen]) - orig_scriptSig_sigops; if (tmpl->txns_sigops >= 0 && tmpl->txns_sigops + sigops_counted > tmpl->sigoplimit) { // Overflowed :( if (out == in) { // Revert it! out[cbScriptSigLen] -= appendsz; memmove(&out[cbPostScriptSig], outPostScriptSig, insz - cbPostScriptSig); } return false; } if (sigops_counted_p) { *sigops_counted_p = sigops_counted; } return true; } ssize_t blkmk_append_coinbase_safe2(blktemplate_t * const tmpl, const void * const append, const size_t appendsz, int extranoncesz, const bool merkle_only) { if (!(tmpl->mutations & (BMM_CBAPPEND | BMM_CBSET))) return -1; size_t datasz = tmpl->cbtxn->datasz; if (extranoncesz == sizeof(unsigned int)) { ++extranoncesz; } else if (!merkle_only) { if (extranoncesz < sizeof(unsigned int)) extranoncesz = sizeof(unsigned int); } if (tmpl->cbtxn->datasz <= cbScriptSigLen || tmpl->cbtxn->datasz <= cbScriptSigLen + tmpl->cbtxn->data[cbScriptSigLen]) { return -6; } if (extranoncesz > libblkmaker_coinbase_size_limit || tmpl->cbtxn->data[cbScriptSigLen] > libblkmaker_coinbase_size_limit || extranoncesz + tmpl->cbtxn->data[cbScriptSigLen] > libblkmaker_coinbase_size_limit) { return -5; } size_t availsz = libblkmaker_coinbase_size_limit - extranoncesz - tmpl->cbtxn->data[cbScriptSigLen]; { const unsigned long pretx_size = libblkmaker_blkheader_size + blkmk_varint_encode_size(1 + tmpl->txncount); const size_t current_blocksize = pretx_size + tmpl->cbtxn->datasz + tmpl->txns_datasz; if (current_blocksize > tmpl->sizelimit) { return -4; } const size_t availsz2 = tmpl->sizelimit - current_blocksize; if (availsz2 < availsz) { availsz = availsz2; } } if (appendsz > availsz) return availsz; void *newp = realloc(tmpl->cbtxn->data, datasz + appendsz); if (!newp) return -2; tmpl->cbtxn->data = newp; if (!_blkmk_append_cb(tmpl, newp, append, appendsz, NULL, &tmpl->cbtxn->sigops_)) return -3; tmpl->cbtxn->datasz += appendsz; return availsz; } ssize_t blkmk_append_coinbase_safe(blktemplate_t * const tmpl, const void * const append, const size_t appendsz) { return blkmk_append_coinbase_safe2(tmpl, append, appendsz, 0, false); } bool _blkmk_extranonce(blktemplate_t *tmpl, void *vout, unsigned int workid, size_t *offs) { unsigned char *in = tmpl->cbtxn->data; size_t insz = tmpl->cbtxn->datasz; if (!workid) { memcpy(vout, in, insz); *offs += insz; return true; } if (!_blkmk_append_cb(tmpl, vout, &workid, sizeof(workid), NULL, NULL)) return false; *offs += insz + sizeof(workid); return true; } static void blkmk_set_times(blktemplate_t *tmpl, void * const out_hdrbuf, const time_t usetime, int16_t * const out_expire, const bool can_roll_ntime) { double time_passed = difftime(usetime, tmpl->_time_rcvd); blktime_t timehdr = tmpl->curtime + time_passed; if (timehdr > tmpl->maxtime) timehdr = tmpl->maxtime; my_htole32(out_hdrbuf, timehdr); if (out_expire) { *out_expire = tmpl->expires - time_passed - 1; if (can_roll_ntime) { // If the caller can roll the time header, we need to expire before reaching the maxtime int16_t maxtime_expire_limit = (tmpl->maxtime - timehdr) + 1; if (*out_expire > maxtime_expire_limit) *out_expire = maxtime_expire_limit; } } } bool blkmk_sample_data_(blktemplate_t * const tmpl, uint8_t * const cbuf, const unsigned int dataid) { my_htole32(&cbuf[0], tmpl->version); memcpy(&cbuf[4], &tmpl->prevblk, 32); unsigned char cbtxndata[tmpl->cbtxn->datasz + sizeof(dataid)]; size_t cbtxndatasz = 0; if (!_blkmk_extranonce(tmpl, cbtxndata, dataid, &cbtxndatasz)) return false; if (!build_merkle_root(&cbuf[36], tmpl, cbtxndata, cbtxndatasz)) return false; my_htole32(&cbuf[0x44], tmpl->curtime); memcpy(&cbuf[72], &tmpl->diffbits, 4); return true; } size_t blkmk_get_data(blktemplate_t *tmpl, void *buf, size_t bufsz, time_t usetime, int16_t *out_expire, unsigned int *out_dataid) { if (!(blkmk_time_left(tmpl, usetime) && blkmk_work_left(tmpl) && tmpl->cbtxn)) return 0; if (bufsz < 76) return 76; if (tmpl->cbtxn->datasz > cbScriptSigLen && tmpl->cbtxn->data[cbScriptSigLen] + sizeof(*out_dataid) < libblkmaker_coinbase_size_minimum) { // Add some padding const size_t padding_required = libblkmaker_coinbase_size_minimum - (tmpl->cbtxn->data[cbScriptSigLen] + sizeof(*out_dataid)); uint8_t padding[padding_required]; static const uint8_t opcode_nop = '\x61'; memset(padding, opcode_nop, padding_required); if (padding_required != blkmk_append_coinbase_safe2(tmpl, padding, padding_required, 0, false)) { return 0; } } unsigned char *cbuf = buf; *out_dataid = tmpl->next_dataid++; if (!blkmk_sample_data_(tmpl, cbuf, *out_dataid)) return 0; blkmk_set_times(tmpl, &cbuf[68], usetime, out_expire, false); return 76; } bool blkmk_get_mdata(blktemplate_t * const tmpl, void * const buf, const size_t bufsz, const time_t usetime, int16_t * const out_expire, void * const _out_cbtxn, size_t * const out_cbtxnsz, size_t * const cbextranonceoffset, int * const out_branchcount, void * const _out_branches, size_t extranoncesz, const bool can_roll_ntime) { if (!(true && blkmk_time_left(tmpl, usetime) && tmpl->cbtxn && blkmk_build_merkle_branches(tmpl) && bufsz >= 76 && (tmpl->mutations & (BMM_CBAPPEND | BMM_CBSET)) )) return false; if (extranoncesz == sizeof(unsigned int)) // Avoid overlapping with blkmk_get_data use ++extranoncesz; if (tmpl->cbtxn->datasz > cbScriptSigLen && tmpl->cbtxn->data[cbScriptSigLen] + extranoncesz < libblkmaker_coinbase_size_minimum) { extranoncesz = libblkmaker_coinbase_size_minimum - tmpl->cbtxn->data[cbScriptSigLen]; } void ** const out_branches = _out_branches; void ** const out_cbtxn = _out_cbtxn; unsigned char *cbuf = buf; my_htole32(&cbuf[0], tmpl->version); memcpy(&cbuf[4], &tmpl->prevblk, 32); *out_cbtxnsz = tmpl->cbtxn->datasz + extranoncesz; *out_cbtxn = malloc(*out_cbtxnsz); if (!*out_cbtxn) return false; unsigned char dummy[extranoncesz]; memset(dummy, 0, extranoncesz); if (!_blkmk_append_cb(tmpl, *out_cbtxn, dummy, extranoncesz, cbextranonceoffset, NULL)) { free(*out_cbtxn); return false; } blkmk_set_times(tmpl, &cbuf[68], usetime, out_expire, can_roll_ntime); memcpy(&cbuf[72], &tmpl->diffbits, 4); *out_branchcount = tmpl->_mrklbranchcount; const size_t branches_bytesz = (sizeof(libblkmaker_hash_t) * tmpl->_mrklbranchcount); *out_branches = malloc(branches_bytesz); if (!*out_branches) { free(*out_cbtxn); return false; } memcpy(*out_branches, tmpl->_mrklbranch, branches_bytesz); return true; } blktime_diff_t blkmk_time_left(const blktemplate_t *tmpl, time_t nowtime) { double age = difftime(nowtime, tmpl->_time_rcvd); if (age >= tmpl->expires) return 0; return tmpl->expires - age; } unsigned long blkmk_work_left(const blktemplate_t *tmpl) { if (!tmpl->version) return 0; if (!(tmpl->mutations & (BMM_CBAPPEND | BMM_CBSET))) return (tmpl->next_dataid) ? 0 : 1; return UINT_MAX - tmpl->next_dataid; } static char *blkmk_assemble_submission2_internal(blktemplate_t * const tmpl, const unsigned char * const data, const void * const extranonce, const size_t extranoncesz, blknonce_t nonce, const bool foreign) { const bool incl_gentxn = (foreign || (!(tmpl->mutations & BMAb_TRUNCATE && !extranoncesz))); const bool incl_alltxn = (foreign || !(tmpl->mutations & BMAb_COINBASE)); size_t blkbuf_sz = libblkmaker_blkheader_size; if (incl_gentxn) { blkbuf_sz += max_varint_size /* tx count */; blkbuf_sz += tmpl->cbtxn->datasz + extranoncesz; if (incl_alltxn) { blkbuf_sz += tmpl->txns_datasz; } } unsigned char * const blk = malloc(blkbuf_sz); if (!blk) { return NULL; } const size_t header_before_nonce_sz = libblkmaker_blkheader_size - sizeof(nonce); memcpy(blk, data, header_before_nonce_sz); nonce = htonl(nonce); memcpy(&blk[header_before_nonce_sz], &nonce, sizeof(nonce)); size_t offs = libblkmaker_blkheader_size; if (incl_gentxn) { offs += varintEncode(&blk[offs], 1 + tmpl->txncount); // Essentially _blkmk_extranonce if (extranoncesz) { if (!_blkmk_append_cb(tmpl, &blk[offs], extranonce, extranoncesz, NULL, NULL)) { free(blk); return NULL; } offs += tmpl->cbtxn->datasz + extranoncesz; } else { memcpy(&blk[offs], tmpl->cbtxn->data, tmpl->cbtxn->datasz); offs += tmpl->cbtxn->datasz; } if (incl_alltxn) { for (unsigned long i = 0; i < tmpl->txncount; ++i) { memcpy(&blk[offs], tmpl->txns[i].data, tmpl->txns[i].datasz); offs += tmpl->txns[i].datasz; } } } char *blkhex = malloc((offs * 2) + 1); _blkmk_bin2hex(blkhex, blk, offs); free(blk); return blkhex; } char *blkmk_assemble_submission2_(blktemplate_t * const tmpl, const unsigned char * const data, const void *extranonce, size_t extranoncesz, const unsigned int dataid, const blknonce_t nonce, const bool foreign) { if (dataid) { if (extranoncesz) { // Cannot specify both! return NULL; } extranonce = &dataid; extranoncesz = sizeof(dataid); } else if (extranoncesz == sizeof(unsigned int)) { // Avoid overlapping with blkmk_get_data use unsigned char extended_extranonce[extranoncesz + 1]; memcpy(extended_extranonce, extranonce, extranoncesz); extended_extranonce[extranoncesz] = 0; return blkmk_assemble_submission2_internal(tmpl, data, extended_extranonce, extranoncesz + 1, nonce, foreign); } return blkmk_assemble_submission2_internal(tmpl, data, extranonce, extranoncesz, nonce, foreign); }