Bitcoin Core  27.99.0
P2P Digital Currency
core_read.cpp
Go to the documentation of this file.
1 // Copyright (c) 2009-2022 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 <primitives/block.h>
9 #include <script/script.h>
10 #include <script/sign.h>
11 #include <serialize.h>
12 #include <streams.h>
13 #include <util/result.h>
14 #include <util/strencodings.h>
15 
16 #include <algorithm>
17 #include <string>
18 
19 namespace {
20 class OpCodeParser
21 {
22 private:
23  std::map<std::string, opcodetype> mapOpNames;
24 
25 public:
26  OpCodeParser()
27  {
28  for (unsigned int op = 0; op <= MAX_OPCODE; ++op) {
29  // Allow OP_RESERVED to get into mapOpNames
30  if (op < OP_NOP && op != OP_RESERVED) {
31  continue;
32  }
33 
34  std::string strName = GetOpName(static_cast<opcodetype>(op));
35  if (strName == "OP_UNKNOWN") {
36  continue;
37  }
38  mapOpNames[strName] = static_cast<opcodetype>(op);
39  // Convenience: OP_ADD and just ADD are both recognized:
40  if (strName.compare(0, 3, "OP_") == 0) { // strName starts with "OP_"
41  mapOpNames[strName.substr(3)] = static_cast<opcodetype>(op);
42  }
43  }
44  }
45  opcodetype Parse(const std::string& s) const
46  {
47  auto it = mapOpNames.find(s);
48  if (it == mapOpNames.end()) throw std::runtime_error("script parse error: unknown opcode");
49  return it->second;
50  }
51 };
52 
53 opcodetype ParseOpCode(const std::string& s)
54 {
55  static const OpCodeParser ocp;
56  return ocp.Parse(s);
57 }
58 
59 } // namespace
60 
61 CScript ParseScript(const std::string& s)
62 {
63  CScript result;
64 
65  std::vector<std::string> words = SplitString(s, " \t\n");
66 
67  for (const std::string& w : words) {
68  if (w.empty()) {
69  // Empty string, ignore. (SplitString doesn't combine multiple separators)
70  } else if (std::all_of(w.begin(), w.end(), ::IsDigit) ||
71  (w.front() == '-' && w.size() > 1 && std::all_of(w.begin() + 1, w.end(), ::IsDigit)))
72  {
73  // Number
74  const auto num{ToIntegral<int64_t>(w)};
75 
76  // limit the range of numbers ParseScript accepts in decimal
77  // since numbers outside -0xFFFFFFFF...0xFFFFFFFF are illegal in scripts
78  if (!num.has_value() || num > int64_t{0xffffffff} || num < -1 * int64_t{0xffffffff}) {
79  throw std::runtime_error("script parse error: decimal numeric value only allowed in the "
80  "range -0xFFFFFFFF...0xFFFFFFFF");
81  }
82 
83  result << num.value();
84  } else if (w.substr(0, 2) == "0x" && w.size() > 2 && IsHex(std::string(w.begin() + 2, w.end()))) {
85  // Raw hex data, inserted NOT pushed onto stack:
86  std::vector<unsigned char> raw = ParseHex(std::string(w.begin() + 2, w.end()));
87  result.insert(result.end(), raw.begin(), raw.end());
88  } else if (w.size() >= 2 && w.front() == '\'' && w.back() == '\'') {
89  // Single-quoted string, pushed as data. NOTE: this is poor-man's
90  // parsing, spaces/tabs/newlines in single-quoted strings won't work.
91  std::vector<unsigned char> value(w.begin() + 1, w.end() - 1);
92  result << value;
93  } else {
94  // opcode, e.g. OP_ADD or ADD:
95  result << ParseOpCode(w);
96  }
97  }
98 
99  return result;
100 }
101 
102 // Check that all of the input and output scripts of a transaction contains valid opcodes
104 {
105  // Check input scripts for non-coinbase txs
106  if (!CTransaction(tx).IsCoinBase()) {
107  for (unsigned int i = 0; i < tx.vin.size(); i++) {
108  if (!tx.vin[i].scriptSig.HasValidOps() || tx.vin[i].scriptSig.size() > MAX_SCRIPT_SIZE) {
109  return false;
110  }
111  }
112  }
113  // Check output scripts
114  for (unsigned int i = 0; i < tx.vout.size(); i++) {
115  if (!tx.vout[i].scriptPubKey.HasValidOps() || tx.vout[i].scriptPubKey.size() > MAX_SCRIPT_SIZE) {
116  return false;
117  }
118  }
119 
120  return true;
121 }
122 
123 static bool DecodeTx(CMutableTransaction& tx, const std::vector<unsigned char>& tx_data, bool try_no_witness, bool try_witness)
124 {
125  // General strategy:
126  // - Decode both with extended serialization (which interprets the 0x0001 tag as a marker for
127  // the presence of witnesses) and with legacy serialization (which interprets the tag as a
128  // 0-input 1-output incomplete transaction).
129  // - Restricted by try_no_witness (which disables legacy if false) and try_witness (which
130  // disables extended if false).
131  // - Ignore serializations that do not fully consume the hex string.
132  // - If neither succeeds, fail.
133  // - If only one succeeds, return that one.
134  // - If both decode attempts succeed:
135  // - If only one passes the CheckTxScriptsSanity check, return that one.
136  // - If neither or both pass CheckTxScriptsSanity, return the extended one.
137 
138  CMutableTransaction tx_extended, tx_legacy;
139  bool ok_extended = false, ok_legacy = false;
140 
141  // Try decoding with extended serialization support, and remember if the result successfully
142  // consumes the entire input.
143  if (try_witness) {
144  DataStream ssData(tx_data);
145  try {
146  ssData >> TX_WITH_WITNESS(tx_extended);
147  if (ssData.empty()) ok_extended = true;
148  } catch (const std::exception&) {
149  // Fall through.
150  }
151  }
152 
153  // Optimization: if extended decoding succeeded and the result passes CheckTxScriptsSanity,
154  // don't bother decoding the other way.
155  if (ok_extended && CheckTxScriptsSanity(tx_extended)) {
156  tx = std::move(tx_extended);
157  return true;
158  }
159 
160  // Try decoding with legacy serialization, and remember if the result successfully consumes the entire input.
161  if (try_no_witness) {
162  DataStream ssData(tx_data);
163  try {
164  ssData >> TX_NO_WITNESS(tx_legacy);
165  if (ssData.empty()) ok_legacy = true;
166  } catch (const std::exception&) {
167  // Fall through.
168  }
169  }
170 
171  // If legacy decoding succeeded and passes CheckTxScriptsSanity, that's our answer, as we know
172  // at this point that extended decoding either failed or doesn't pass the sanity check.
173  if (ok_legacy && CheckTxScriptsSanity(tx_legacy)) {
174  tx = std::move(tx_legacy);
175  return true;
176  }
177 
178  // If extended decoding succeeded, and neither decoding passes sanity, return the extended one.
179  if (ok_extended) {
180  tx = std::move(tx_extended);
181  return true;
182  }
183 
184  // If legacy decoding succeeded and extended didn't, return the legacy one.
185  if (ok_legacy) {
186  tx = std::move(tx_legacy);
187  return true;
188  }
189 
190  // If none succeeded, we failed.
191  return false;
192 }
193 
194 bool DecodeHexTx(CMutableTransaction& tx, const std::string& hex_tx, bool try_no_witness, bool try_witness)
195 {
196  if (!IsHex(hex_tx)) {
197  return false;
198  }
199 
200  std::vector<unsigned char> txData(ParseHex(hex_tx));
201  return DecodeTx(tx, txData, try_no_witness, try_witness);
202 }
203 
204 bool DecodeHexBlockHeader(CBlockHeader& header, const std::string& hex_header)
205 {
206  if (!IsHex(hex_header)) return false;
207 
208  const std::vector<unsigned char> header_data{ParseHex(hex_header)};
209  DataStream ser_header{header_data};
210  try {
211  ser_header >> header;
212  } catch (const std::exception&) {
213  return false;
214  }
215  return true;
216 }
217 
218 bool DecodeHexBlk(CBlock& block, const std::string& strHexBlk)
219 {
220  if (!IsHex(strHexBlk))
221  return false;
222 
223  std::vector<unsigned char> blockData(ParseHex(strHexBlk));
224  DataStream ssBlock(blockData);
225  try {
226  ssBlock >> TX_WITH_WITNESS(block);
227  }
228  catch (const std::exception&) {
229  return false;
230  }
231 
232  return true;
233 }
234 
235 bool ParseHashStr(const std::string& strHex, uint256& result)
236 {
237  if ((strHex.size() != 64) || !IsHex(strHex))
238  return false;
239 
240  result.SetHex(strHex);
241  return true;
242 }
243 
244 util::Result<int> SighashFromStr(const std::string& sighash)
245 {
246  static std::map<std::string, int> map_sighash_values = {
247  {std::string("DEFAULT"), int(SIGHASH_DEFAULT)},
248  {std::string("ALL"), int(SIGHASH_ALL)},
249  {std::string("ALL|ANYONECANPAY"), int(SIGHASH_ALL|SIGHASH_ANYONECANPAY)},
250  {std::string("NONE"), int(SIGHASH_NONE)},
251  {std::string("NONE|ANYONECANPAY"), int(SIGHASH_NONE|SIGHASH_ANYONECANPAY)},
252  {std::string("SINGLE"), int(SIGHASH_SINGLE)},
253  {std::string("SINGLE|ANYONECANPAY"), int(SIGHASH_SINGLE|SIGHASH_ANYONECANPAY)},
254  };
255  const auto& it = map_sighash_values.find(sighash);
256  if (it != map_sighash_values.end()) {
257  return it->second;
258  } else {
259  return util::Error{Untranslated(sighash + " is not a valid sighash parameter.")};
260  }
261 }
Nodes collect new transactions into a block, hash them into a hash tree, and scan through nonce value...
Definition: block.h:22
Definition: block.h:69
Serialized script, used inside transaction inputs and outputs.
Definition: script.h:414
The basic transaction that is broadcasted on the network and contained in blocks.
Definition: transaction.h:296
Double ended buffer combining vector and stream-like interfaces.
Definition: streams.h:147
bool empty() const
Definition: streams.h:182
void SetHex(const char *psz)
Definition: uint256.cpp:21
iterator end()
Definition: prevector.h:306
iterator insert(iterator pos, const T &value)
Definition: prevector.h:361
256-bit opaque blob.
Definition: uint256.h:106
static UniValue Parse(std::string_view raw)
Parse string to UniValue or throw runtime_error if string contains invalid JSON.
Definition: client.cpp:313
CScript ParseScript(const std::string &s)
Definition: core_read.cpp:61
util::Result< int > SighashFromStr(const std::string &sighash)
Definition: core_read.cpp:244
static bool CheckTxScriptsSanity(const CMutableTransaction &tx)
Definition: core_read.cpp:103
bool DecodeHexTx(CMutableTransaction &tx, const std::string &hex_tx, bool try_no_witness, bool try_witness)
Definition: core_read.cpp:194
bool DecodeHexBlockHeader(CBlockHeader &header, const std::string &hex_header)
Definition: core_read.cpp:204
bool ParseHashStr(const std::string &strHex, uint256 &result)
Parse a hex string into 256 bits.
Definition: core_read.cpp:235
static bool DecodeTx(CMutableTransaction &tx, const std::vector< unsigned char > &tx_data, bool try_no_witness, bool try_witness)
Definition: core_read.cpp:123
bool DecodeHexBlk(CBlock &block, const std::string &strHexBlk)
Definition: core_read.cpp:218
@ SIGHASH_ANYONECANPAY
Definition: interpreter.h:33
@ SIGHASH_DEFAULT
Taproot only; implied when sighash byte is missing, and equivalent to SIGHASH_ALL.
Definition: interpreter.h:35
@ SIGHASH_ALL
Definition: interpreter.h:30
@ SIGHASH_NONE
Definition: interpreter.h:31
@ SIGHASH_SINGLE
Definition: interpreter.h:32
static constexpr TransactionSerParams TX_NO_WITNESS
Definition: transaction.h:196
static constexpr TransactionSerParams TX_WITH_WITNESS
Definition: transaction.h:195
std::string GetOpName(opcodetype opcode)
Definition: script.cpp:18
static const unsigned int MAX_OPCODE
Definition: script.h:215
static const int MAX_SCRIPT_SIZE
Definition: script.h:39
opcodetype
Script opcodes.
Definition: script.h:73
@ OP_NOP
Definition: script.h:101
@ OP_RESERVED
Definition: script.h:81
constexpr bool IsDigit(char c)
Tests if the given character is a decimal digit.
Definition: strencodings.h:152
std::vector< Byte > ParseHex(std::string_view hex_str)
Like TryParseHex, but returns an empty vector on invalid input.
Definition: strencodings.h:65
std::vector< std::string > SplitString(std::string_view str, char sep)
Definition: string.h:21
A mutable version of CTransaction.
Definition: transaction.h:378
std::vector< CTxOut > vout
Definition: transaction.h:380
std::vector< CTxIn > vin
Definition: transaction.h:379
bilingual_str Untranslated(std::string original)
Mark a bilingual_str as untranslated.
Definition: translation.h:48
bool IsHex(std::string_view str)