core_io.cpp raw
1 // Copyright (c) 2009-present The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5 #include <core_io.h>
6
7 #include <addresstype.h>
8 #include <coins.h>
9 #include <consensus/amount.h>
10 #include <consensus/consensus.h>
11 #include <consensus/validation.h>
12 #include <crypto/hex_base.h>
13 #include <key_io.h>
14 #include <prevector.h>
15 #include <primitives/block.h>
16 #include <primitives/transaction.h>
17 #include <script/descriptor.h>
18 #include <script/interpreter.h>
19 #include <script/script.h>
20 #include <script/signingprovider.h>
21 #include <script/solver.h>
22 #include <serialize.h>
23 #include <streams.h>
24 #include <tinyformat.h>
25 #include <uint256.h>
26 #include <undo.h>
27 #include <univalue.h>
28 #include <util/check.h>
29 #include <util/result.h>
30 #include <util/strencodings.h>
31 #include <util/string.h>
32 #include <util/translation.h>
33
34 #include <algorithm>
35 #include <compare>
36 #include <cstdint>
37 #include <exception>
38 #include <functional>
39 #include <map>
40 #include <memory>
41 #include <optional>
42 #include <span>
43 #include <stdexcept>
44 #include <string>
45 #include <utility>
46 #include <vector>
47
48 using util::SplitString;
49
50 namespace {
51 class OpCodeParser
52 {
53 private:
54 std::map<std::string, opcodetype> mapOpNames;
55
56 public:
57 OpCodeParser()
58 {
59 for (unsigned int op = 0; op <= MAX_OPCODE; ++op) {
60 // Allow OP_RESERVED to get into mapOpNames
61 if (op < OP_NOP && op != OP_RESERVED) {
62 continue;
63 }
64
65 std::string strName = GetOpName(static_cast<opcodetype>(op));
66 if (strName == "OP_UNKNOWN") {
67 continue;
68 }
69 mapOpNames[strName] = static_cast<opcodetype>(op);
70 // Convenience: OP_ADD and just ADD are both recognized:
71 if (strName.starts_with("OP_")) {
72 mapOpNames[strName.substr(3)] = static_cast<opcodetype>(op);
73 }
74 }
75 }
76 opcodetype Parse(const std::string& s) const
77 {
78 auto it = mapOpNames.find(s);
79 if (it == mapOpNames.end()) throw std::runtime_error("script parse error: unknown opcode");
80 return it->second;
81 }
82 };
83
84 opcodetype ParseOpCode(const std::string& s)
85 {
86 static const OpCodeParser ocp;
87 return ocp.Parse(s);
88 }
89
90 } // namespace
91
92 CScript ParseScript(const std::string& s)
93 {
94 CScript result;
95
96 std::vector<std::string> words = SplitString(s, " \t\n");
97
98 for (const std::string& w : words) {
99 if (w.empty()) {
100 // Empty string, ignore. (SplitString doesn't combine multiple separators)
101 } else if (std::all_of(w.begin(), w.end(), ::IsDigit) ||
102 (w.front() == '-' && w.size() > 1 && std::all_of(w.begin() + 1, w.end(), ::IsDigit)))
103 {
104 // Number
105 const auto num{ToIntegral<int64_t>(w)};
106
107 // limit the range of numbers ParseScript accepts in decimal
108 // since numbers outside -0xFFFFFFFF...0xFFFFFFFF are illegal in scripts
109 if (!num.has_value() || num > int64_t{0xffffffff} || num < -1 * int64_t{0xffffffff}) {
110 throw std::runtime_error("script parse error: decimal numeric value only allowed in the "
111 "range -0xFFFFFFFF...0xFFFFFFFF");
112 }
113
114 result << num.value();
115 } else if (w.starts_with("0x") && w.size() > 2 && IsHex(std::string(w.begin() + 2, w.end()))) {
116 // Raw hex data, inserted NOT pushed onto stack:
117 std::vector<unsigned char> raw = ParseHex(std::string(w.begin() + 2, w.end()));
118 result.insert(result.end(), raw.begin(), raw.end());
119 } else if (w.size() >= 2 && w.front() == '\'' && w.back() == '\'') {
120 // Single-quoted string, pushed as data. NOTE: this is poor-man's
121 // parsing, spaces/tabs/newlines in single-quoted strings won't work.
122 std::vector<unsigned char> value(w.begin() + 1, w.end() - 1);
123 result << value;
124 } else {
125 // opcode, e.g. OP_ADD or ADD:
126 result << ParseOpCode(w);
127 }
128 }
129
130 return result;
131 }
132
133 /// Check that all of the input and output scripts of a transaction contain valid opcodes
134 static bool CheckTxScriptsSanity(const CMutableTransaction& tx)
135 {
136 // Check input scripts for non-coinbase txs
137 if (!CTransaction(tx).IsCoinBase()) {
138 for (unsigned int i = 0; i < tx.vin.size(); i++) {
139 if (!tx.vin[i].scriptSig.HasValidOps() || tx.vin[i].scriptSig.size() > MAX_SCRIPT_SIZE) {
140 return false;
141 }
142 }
143 }
144 // Check output scripts
145 for (unsigned int i = 0; i < tx.vout.size(); i++) {
146 if (!tx.vout[i].scriptPubKey.HasValidOps() || tx.vout[i].scriptPubKey.size() > MAX_SCRIPT_SIZE) {
147 return false;
148 }
149 }
150
151 return true;
152 }
153
154 static bool DecodeTx(CMutableTransaction& tx, const std::vector<unsigned char>& tx_data, bool try_no_witness, bool try_witness)
155 {
156 // General strategy:
157 // - Decode both with extended serialization (which interprets the 0x0001 tag as a marker for
158 // the presence of witnesses) and with legacy serialization (which interprets the tag as a
159 // 0-input 1-output incomplete transaction).
160 // - Restricted by try_no_witness (which disables legacy if false) and try_witness (which
161 // disables extended if false).
162 // - Ignore serializations that do not fully consume the hex string.
163 // - If neither succeeds, fail.
164 // - If only one succeeds, return that one.
165 // - If both decode attempts succeed:
166 // - If only one passes the CheckTxScriptsSanity check, return that one.
167 // - If neither or both pass CheckTxScriptsSanity, return the extended one.
168
169 CMutableTransaction tx_extended, tx_legacy;
170 bool ok_extended = false, ok_legacy = false;
171
172 // Try decoding with extended serialization support, and remember if the result successfully
173 // consumes the entire input.
174 if (try_witness) {
175 SpanReader ssData{tx_data};
176 try {
177 ssData >> TX_WITH_WITNESS(tx_extended);
178 if (ssData.empty()) ok_extended = true;
179 } catch (const std::exception&) {
180 // Fall through.
181 }
182 }
183
184 // Optimization: if extended decoding succeeded and the result passes CheckTxScriptsSanity,
185 // don't bother decoding the other way.
186 if (ok_extended && CheckTxScriptsSanity(tx_extended)) {
187 tx = std::move(tx_extended);
188 return true;
189 }
190
191 // Try decoding with legacy serialization, and remember if the result successfully consumes the entire input.
192 if (try_no_witness) {
193 SpanReader ssData{tx_data};
194 try {
195 ssData >> TX_NO_WITNESS(tx_legacy);
196 if (ssData.empty()) ok_legacy = true;
197 } catch (const std::exception&) {
198 // Fall through.
199 }
200 }
201
202 // If legacy decoding succeeded and passes CheckTxScriptsSanity, that's our answer, as we know
203 // at this point that extended decoding either failed or doesn't pass the sanity check.
204 if (ok_legacy && CheckTxScriptsSanity(tx_legacy)) {
205 tx = std::move(tx_legacy);
206 return true;
207 }
208
209 // If extended decoding succeeded, and neither decoding passes sanity, return the extended one.
210 if (ok_extended) {
211 tx = std::move(tx_extended);
212 return true;
213 }
214
215 // If legacy decoding succeeded and extended didn't, return the legacy one.
216 if (ok_legacy) {
217 tx = std::move(tx_legacy);
218 return true;
219 }
220
221 // If none succeeded, we failed.
222 return false;
223 }
224
225 bool DecodeHexTx(CMutableTransaction& tx, const std::string& hex_tx, bool try_no_witness, bool try_witness)
226 {
227 if (!IsHex(hex_tx)) {
228 return false;
229 }
230
231 std::vector<unsigned char> txData(ParseHex(hex_tx));
232 return DecodeTx(tx, txData, try_no_witness, try_witness);
233 }
234
235 bool DecodeHexBlockHeader(CBlockHeader& header, const std::string& hex_header)
236 {
237 if (!IsHex(hex_header)) return false;
238
239 const std::vector<unsigned char> header_data{ParseHex(hex_header)};
240 try {
241 SpanReader{header_data} >> header;
242 } catch (const std::exception&) {
243 return false;
244 }
245 return true;
246 }
247
248 bool DecodeHexBlk(CBlock& block, const std::string& strHexBlk)
249 {
250 if (!IsHex(strHexBlk))
251 return false;
252
253 std::vector<unsigned char> blockData(ParseHex(strHexBlk));
254 try {
255 SpanReader{blockData} >> TX_WITH_WITNESS(block);
256 }
257 catch (const std::exception&) {
258 return false;
259 }
260
261 return true;
262 }
263
264 util::Result<int> SighashFromStr(const std::string& sighash)
265 {
266 static const std::map<std::string, int> map_sighash_values = {
267 {std::string("DEFAULT"), int(SIGHASH_DEFAULT)},
268 {std::string("ALL"), int(SIGHASH_ALL)},
269 {std::string("ALL|ANYONECANPAY"), int(SIGHASH_ALL|SIGHASH_ANYONECANPAY)},
270 {std::string("NONE"), int(SIGHASH_NONE)},
271 {std::string("NONE|ANYONECANPAY"), int(SIGHASH_NONE|SIGHASH_ANYONECANPAY)},
272 {std::string("SINGLE"), int(SIGHASH_SINGLE)},
273 {std::string("SINGLE|ANYONECANPAY"), int(SIGHASH_SINGLE|SIGHASH_ANYONECANPAY)},
274 };
275 const auto& it = map_sighash_values.find(sighash);
276 if (it != map_sighash_values.end()) {
277 return it->second;
278 } else {
279 return util::Error{Untranslated("'" + sighash + "' is not a valid sighash parameter.")};
280 }
281 }
282
283 UniValue ValueFromAmount(const CAmount amount)
284 {
285 static_assert(COIN > 1);
286 int64_t quotient = amount / COIN;
287 int64_t remainder = amount % COIN;
288 if (amount < 0) {
289 quotient = -quotient;
290 remainder = -remainder;
291 }
292 return UniValue(UniValue::VNUM,
293 strprintf("%s%d.%08d", amount < 0 ? "-" : "", quotient, remainder));
294 }
295
296 std::string FormatScript(const CScript& script)
297 {
298 std::string ret;
299 CScript::const_iterator it = script.begin();
300 opcodetype op;
301 while (it != script.end()) {
302 CScript::const_iterator it2 = it;
303 std::vector<unsigned char> vch;
304 if (script.GetOp(it, op, vch)) {
305 if (op == OP_0) {
306 ret += "0 ";
307 continue;
308 } else if ((op >= OP_1 && op <= OP_16) || op == OP_1NEGATE) {
309 ret += strprintf("%i ", op - OP_1NEGATE - 1);
310 continue;
311 } else if (op >= OP_NOP && op <= OP_NOP10) {
312 std::string str(GetOpName(op));
313 if (str.substr(0, 3) == std::string("OP_")) {
314 ret += str.substr(3, std::string::npos) + " ";
315 continue;
316 }
317 }
318 if (vch.size() > 0) {
319 ret += strprintf("0x%x 0x%x ", HexStr(std::vector<uint8_t>(it2, it - vch.size())),
320 HexStr(std::vector<uint8_t>(it - vch.size(), it)));
321 } else {
322 ret += strprintf("0x%x ", HexStr(std::vector<uint8_t>(it2, it)));
323 }
324 continue;
325 }
326 ret += strprintf("0x%x ", HexStr(std::vector<uint8_t>(it2, script.end())));
327 break;
328 }
329 return ret.substr(0, ret.empty() ? ret.npos : ret.size() - 1);
330 }
331
332 const std::map<unsigned char, std::string> mapSigHashTypes = {
333 {static_cast<unsigned char>(SIGHASH_ALL), std::string("ALL")},
334 {static_cast<unsigned char>(SIGHASH_ALL|SIGHASH_ANYONECANPAY), std::string("ALL|ANYONECANPAY")},
335 {static_cast<unsigned char>(SIGHASH_NONE), std::string("NONE")},
336 {static_cast<unsigned char>(SIGHASH_NONE|SIGHASH_ANYONECANPAY), std::string("NONE|ANYONECANPAY")},
337 {static_cast<unsigned char>(SIGHASH_SINGLE), std::string("SINGLE")},
338 {static_cast<unsigned char>(SIGHASH_SINGLE|SIGHASH_ANYONECANPAY), std::string("SINGLE|ANYONECANPAY")},
339 };
340
341 std::string SighashToStr(unsigned char sighash_type)
342 {
343 const auto& it = mapSigHashTypes.find(sighash_type);
344 if (it == mapSigHashTypes.end()) return "";
345 return it->second;
346 }
347
348 /**
349 * Create the assembly string representation of a CScript object.
350 * @param[in] script CScript object to convert into the asm string representation.
351 * @param[in] fAttemptSighashDecode Whether to attempt to decode sighash types on data within the script that matches the format
352 * of a signature. Only pass true for scripts you believe could contain signatures. For example,
353 * pass false, or omit the this argument (defaults to false), for scriptPubKeys.
354 */
355 std::string ScriptToAsmStr(const CScript& script, const bool fAttemptSighashDecode)
356 {
357 std::string str;
358 opcodetype opcode;
359 std::vector<unsigned char> vch;
360 CScript::const_iterator pc = script.begin();
361 while (pc < script.end()) {
362 if (!str.empty()) {
363 str += " ";
364 }
365 if (!script.GetOp(pc, opcode, vch)) {
366 str += "[error]";
367 return str;
368 }
369 if (0 <= opcode && opcode <= OP_PUSHDATA4) {
370 if (vch.size() <= static_cast<std::vector<unsigned char>::size_type>(4)) {
371 str += strprintf("%d", CScriptNum(vch, false).getint());
372 } else {
373 // the IsUnspendable check makes sure not to try to decode OP_RETURN data that may match the format of a signature
374 if (fAttemptSighashDecode && !script.IsUnspendable()) {
375 std::string strSigHashDecode;
376 // goal: only attempt to decode a defined sighash type from data that looks like a signature within a scriptSig.
377 // this won't decode correctly formatted public keys in Pubkey or Multisig scripts due to
378 // the restrictions on the pubkey formats (see IsCompressedOrUncompressedPubKey) being incongruous with the
379 // checks in CheckSignatureEncoding.
380 if (CheckSignatureEncoding(vch, SCRIPT_VERIFY_STRICTENC, nullptr)) {
381 const unsigned char chSigHashType = vch.back();
382 const auto it = mapSigHashTypes.find(chSigHashType);
383 if (it != mapSigHashTypes.end()) {
384 strSigHashDecode = "[" + it->second + "]";
385 vch.pop_back(); // remove the sighash type byte. it will be replaced by the decode.
386 }
387 }
388 str += HexStr(vch) + strSigHashDecode;
389 } else {
390 str += HexStr(vch);
391 }
392 }
393 } else {
394 str += GetOpName(opcode);
395 }
396 }
397 return str;
398 }
399
400 std::string EncodeHexTx(const CTransaction& tx)
401 {
402 DataStream ssTx;
403 ssTx << TX_WITH_WITNESS(tx);
404 return HexStr(ssTx);
405 }
406
407 void ScriptToUniv(const CScript& script, UniValue& out, bool include_hex, bool include_address, const SigningProvider* provider)
408 {
409 CTxDestination address;
410
411 out.pushKV("asm", ScriptToAsmStr(script));
412 if (include_address) {
413 out.pushKV("desc", InferDescriptor(script, provider ? *provider : DUMMY_SIGNING_PROVIDER)->ToString());
414 }
415 if (include_hex) {
416 out.pushKV("hex", HexStr(script));
417 }
418
419 std::vector<std::vector<unsigned char>> solns;
420 const TxoutType type{Solver(script, solns)};
421
422 if (include_address && ExtractDestination(script, address) && type != TxoutType::PUBKEY) {
423 out.pushKV("address", EncodeDestination(address));
424 }
425 out.pushKV("type", GetTxnOutputType(type));
426 }
427
428 void TxToUniv(const CTransaction& tx, const uint256& block_hash, UniValue& entry, bool include_hex, const CTxUndo* txundo, TxVerbosity verbosity, std::function<bool(const CTxOut&)> is_change_func)
429 {
430 CHECK_NONFATAL(verbosity >= TxVerbosity::SHOW_DETAILS);
431
432 entry.pushKV("txid", tx.GetHash().GetHex());
433 entry.pushKV("hash", tx.GetWitnessHash().GetHex());
434 entry.pushKV("version", tx.version);
435 entry.pushKV("size", tx.ComputeTotalSize());
436 entry.pushKV("vsize", (GetTransactionWeight(tx) + WITNESS_SCALE_FACTOR - 1) / WITNESS_SCALE_FACTOR);
437 entry.pushKV("weight", GetTransactionWeight(tx));
438 entry.pushKV("locktime", tx.nLockTime);
439
440 UniValue vin{UniValue::VARR};
441 vin.reserve(tx.vin.size());
442
443 // If available, use Undo data to calculate the fee. Note that txundo == nullptr
444 // for coinbase transactions and for transactions where undo data is unavailable.
445 const bool have_undo = txundo != nullptr;
446 CAmount amt_total_in = 0;
447 CAmount amt_total_out = 0;
448
449 for (unsigned int i = 0; i < tx.vin.size(); i++) {
450 const CTxIn& txin = tx.vin[i];
451 UniValue in(UniValue::VOBJ);
452 if (tx.IsCoinBase()) {
453 in.pushKV("coinbase", HexStr(txin.scriptSig));
454 } else {
455 in.pushKV("txid", txin.prevout.hash.GetHex());
456 in.pushKV("vout", txin.prevout.n);
457 UniValue o(UniValue::VOBJ);
458 o.pushKV("asm", ScriptToAsmStr(txin.scriptSig, true));
459 o.pushKV("hex", HexStr(txin.scriptSig));
460 in.pushKV("scriptSig", std::move(o));
461 }
462 if (!tx.vin[i].scriptWitness.IsNull()) {
463 UniValue txinwitness(UniValue::VARR);
464 txinwitness.reserve(tx.vin[i].scriptWitness.stack.size());
465 for (const auto& item : tx.vin[i].scriptWitness.stack) {
466 txinwitness.push_back(HexStr(item));
467 }
468 in.pushKV("txinwitness", std::move(txinwitness));
469 }
470 if (have_undo) {
471 const Coin& prev_coin = txundo->vprevout[i];
472 const CTxOut& prev_txout = prev_coin.out;
473
474 amt_total_in += prev_txout.nValue;
475
476 if (verbosity == TxVerbosity::SHOW_DETAILS_AND_PREVOUT) {
477 UniValue o_script_pub_key(UniValue::VOBJ);
478 ScriptToUniv(prev_txout.scriptPubKey, /*out=*/o_script_pub_key, /*include_hex=*/true, /*include_address=*/true);
479
480 UniValue p(UniValue::VOBJ);
481 p.pushKV("generated", prev_coin.IsCoinBase());
482 p.pushKV("height", prev_coin.nHeight);
483 p.pushKV("value", ValueFromAmount(prev_txout.nValue));
484 p.pushKV("scriptPubKey", std::move(o_script_pub_key));
485 in.pushKV("prevout", std::move(p));
486 }
487 }
488 in.pushKV("sequence", txin.nSequence);
489 vin.push_back(std::move(in));
490 }
491 entry.pushKV("vin", std::move(vin));
492
493 UniValue vout(UniValue::VARR);
494 vout.reserve(tx.vout.size());
495 for (unsigned int i = 0; i < tx.vout.size(); i++) {
496 const CTxOut& txout = tx.vout[i];
497
498 UniValue out(UniValue::VOBJ);
499
500 out.pushKV("value", ValueFromAmount(txout.nValue));
501 out.pushKV("n", i);
502
503 UniValue o(UniValue::VOBJ);
504 ScriptToUniv(txout.scriptPubKey, /*out=*/o, /*include_hex=*/true, /*include_address=*/true);
505 out.pushKV("scriptPubKey", std::move(o));
506
507 if (is_change_func && is_change_func(txout)) {
508 out.pushKV("ischange", true);
509 }
510
511 vout.push_back(std::move(out));
512
513 if (have_undo) {
514 amt_total_out += txout.nValue;
515 }
516 }
517 entry.pushKV("vout", std::move(vout));
518
519 if (have_undo) {
520 const CAmount fee = amt_total_in - amt_total_out;
521 CHECK_NONFATAL(MoneyRange(fee));
522 entry.pushKV("fee", ValueFromAmount(fee));
523 }
524
525 if (!block_hash.IsNull()) {
526 entry.pushKV("blockhash", block_hash.GetHex());
527 }
528
529 if (include_hex) {
530 entry.pushKV("hex", EncodeHexTx(tx)); // The hex-encoded transaction. Used the name "hex" to be consistent with the verbose output of "getrawtransaction".
531 }
532 }
533