Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2022 The Bitcoin Core developers
       3             : // Distributed under the MIT software license, see the accompanying
       4             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       5             : 
       6             : #include <script/bitcoinconsensus.h>
       7             : 
       8             : #include <primitives/transaction.h>
       9             : #include <pubkey.h>
      10             : #include <script/interpreter.h>
      11             : #include <version.h>
      12             : 
      13             : namespace {
      14             : 
      15             : /** A class that deserializes a single CTransaction one time. */
      16             : class TxInputStream
      17             : {
      18             : public:
      19           0 :     TxInputStream(int nVersionIn, const unsigned char *txTo, size_t txToLen) :
      20           0 :     m_version(nVersionIn),
      21           0 :     m_data(txTo),
      22           0 :     m_remaining(txToLen)
      23           0 :     {}
      24             : 
      25           0 :     void read(Span<std::byte> dst)
      26             :     {
      27           0 :         if (dst.size() > m_remaining) {
      28           0 :             throw std::ios_base::failure(std::string(__func__) + ": end of data");
      29             :         }
      30             : 
      31           0 :         if (dst.data() == nullptr) {
      32           0 :             throw std::ios_base::failure(std::string(__func__) + ": bad destination buffer");
      33             :         }
      34             : 
      35           0 :         if (m_data == nullptr) {
      36           0 :             throw std::ios_base::failure(std::string(__func__) + ": bad source buffer");
      37             :         }
      38             : 
      39           0 :         memcpy(dst.data(), m_data, dst.size());
      40           0 :         m_remaining -= dst.size();
      41           0 :         m_data += dst.size();
      42           0 :     }
      43             : 
      44             :     template<typename T>
      45           0 :     TxInputStream& operator>>(T&& obj)
      46             :     {
      47           0 :         ::Unserialize(*this, obj);
      48           0 :         return *this;
      49             :     }
      50             : 
      51           0 :     int GetVersion() const { return m_version; }
      52             : private:
      53             :     const int m_version;
      54             :     const unsigned char* m_data;
      55             :     size_t m_remaining;
      56             : };
      57             : 
      58           0 : inline int set_error(bitcoinconsensus_error* ret, bitcoinconsensus_error serror)
      59             : {
      60           0 :     if (ret)
      61           0 :         *ret = serror;
      62           0 :     return 0;
      63             : }
      64             : 
      65             : } // namespace
      66             : 
      67             : /** Check that all specified flags are part of the libconsensus interface. */
      68           0 : static bool verify_flags(unsigned int flags)
      69             : {
      70           0 :     return (flags & ~(bitcoinconsensus_SCRIPT_FLAGS_VERIFY_ALL)) == 0;
      71             : }
      72             : 
      73           0 : static int verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen, CAmount amount,
      74             :                                     const unsigned char *txTo        , unsigned int txToLen,
      75             :                                     unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
      76             : {
      77           0 :     if (!verify_flags(flags)) {
      78           0 :         return set_error(err, bitcoinconsensus_ERR_INVALID_FLAGS);
      79             :     }
      80             :     try {
      81           0 :         TxInputStream stream(PROTOCOL_VERSION, txTo, txToLen);
      82           0 :         CTransaction tx(deserialize, stream);
      83           0 :         if (nIn >= tx.vin.size())
      84           0 :             return set_error(err, bitcoinconsensus_ERR_TX_INDEX);
      85           0 :         if (GetSerializeSize(tx, PROTOCOL_VERSION) != txToLen)
      86           0 :             return set_error(err, bitcoinconsensus_ERR_TX_SIZE_MISMATCH);
      87             : 
      88             :         // Regardless of the verification result, the tx did not error.
      89           0 :         set_error(err, bitcoinconsensus_ERR_OK);
      90             : 
      91           0 :         PrecomputedTransactionData txdata(tx);
      92           0 :         return VerifyScript(tx.vin[nIn].scriptSig, CScript(scriptPubKey, scriptPubKey + scriptPubKeyLen), &tx.vin[nIn].scriptWitness, flags, TransactionSignatureChecker(&tx, nIn, amount, txdata, MissingDataBehavior::FAIL), nullptr);
      93           0 :     } catch (const std::exception&) {
      94           0 :         return set_error(err, bitcoinconsensus_ERR_TX_DESERIALIZE); // Error deserializing
      95           0 :     }
      96           0 : }
      97             : 
      98           0 : int bitcoinconsensus_verify_script_with_amount(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen, int64_t amount,
      99             :                                     const unsigned char *txTo        , unsigned int txToLen,
     100             :                                     unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
     101             : {
     102           0 :     CAmount am(amount);
     103           0 :     return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
     104             : }
     105             : 
     106             : 
     107           0 : int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
     108             :                                    const unsigned char *txTo        , unsigned int txToLen,
     109             :                                    unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
     110             : {
     111           0 :     if (flags & bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS) {
     112           0 :         return set_error(err, bitcoinconsensus_ERR_AMOUNT_REQUIRED);
     113             :     }
     114             : 
     115           0 :     CAmount am(0);
     116           0 :     return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
     117           0 : }
     118             : 
     119           0 : unsigned int bitcoinconsensus_version()
     120             : {
     121             :     // Just use the API version for now
     122           0 :     return BITCOINCONSENSUS_API_VER;
     123             : }