src/script/bitcoinconsensus.cpp

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2016 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     TxInputStream(int nTypeIn, int nVersionIn, const unsigned char *txTo, size_t txToLen) :
  20     m_type(nTypeIn),
  21     m_version(nVersionIn),
  22     m_data(txTo),
  23     m_remaining(txToLen)
  24     {}
  25
  26     void read(char* pch, size_t nSize)
  27     {
  28         if (nSize > m_remaining)
  29             throw std::ios_base::failure(std::string(__func__) + ": end of data");
  30
  31         if (pch == nullptr)
  32             throw std::ios_base::failure(std::string(__func__) + ": bad destination buffer");
  33
  34         if (m_data == nullptr)
  35             throw std::ios_base::failure(std::string(__func__) + ": bad source buffer");
  36
  37         memcpy(pch, m_data, nSize);
  38         m_remaining -= nSize;
  39         m_data += nSize;
  40     }
  41
  42     template<typename T>
  43     TxInputStream& operator>>(T& obj)
  44     {
  45         ::Unserialize(*this, obj);
  46         return *this;
  47     }
  48
  49     int GetVersion() const { return m_version; }
  50     int GetType() const { return m_type; }
  51 private:
  52     const int m_type;
  53     const int m_version;
  54     const unsigned char* m_data;
  55     size_t m_remaining;
  56 };
  57
  58 inline int set_error(bitcoinconsensus_error* ret, bitcoinconsensus_error serror)
  59 {
  60     if (ret)
  61         *ret = serror;
  62     return 0;
  63 }
  64
  65 struct ECCryptoClosure
  66 {
  67     ECCVerifyHandle handle;
  68 };
  69
  70 ECCryptoClosure instance_of_eccryptoclosure;
  71 } // namespace
  72
  73 /** Check that all specified flags are part of the libconsensus interface. */
  74 static bool verify_flags(unsigned int flags)
  75 {
  76     return (flags & ~(bitcoinconsensus_SCRIPT_FLAGS_VERIFY_ALL)) == 0;
  77 }
  78
  79 static int verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen, CAmount amount,
  80                                     const unsigned char *txTo        , unsigned int txToLen,
  81                                     unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
  82 {
  83     if (!verify_flags(flags)) {
  84         return bitcoinconsensus_ERR_INVALID_FLAGS;
  85     }
  86     try {
  87         TxInputStream stream(SER_NETWORK, PROTOCOL_VERSION, txTo, txToLen);
  88         CTransaction tx(deserialize, stream);
  89         if (nIn >= tx.vin.size())
  90             return set_error(err, bitcoinconsensus_ERR_TX_INDEX);
  91         if (GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION) != txToLen)
  92             return set_error(err, bitcoinconsensus_ERR_TX_SIZE_MISMATCH);
  93
  94         // Regardless of the verification result, the tx did not error.
  95         set_error(err, bitcoinconsensus_ERR_OK);
  96
  97         PrecomputedTransactionData txdata(tx);
  98         return VerifyScript(tx.vin[nIn].scriptSig, CScript(scriptPubKey, scriptPubKey + scriptPubKeyLen), &tx.vin[nIn].scriptWitness, flags, TransactionSignatureChecker(&tx, nIn, amount, txdata), nullptr);
  99     } catch (const std::exception&) {
 100         return set_error(err, bitcoinconsensus_ERR_TX_DESERIALIZE); // Error deserializing
 101     }
 102 }
 103
 104 int bitcoinconsensus_verify_script_with_amount(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen, int64_t amount,
 105                                     const unsigned char *txTo        , unsigned int txToLen,
 106                                     unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
 107 {
 108     CAmount am(amount);
 109     return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
 110 }
 111
 112
 113 int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
 114                                    const unsigned char *txTo        , unsigned int txToLen,
 115                                    unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
 116 {
 117     if (flags & bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS) {
 118         return set_error(err, bitcoinconsensus_ERR_AMOUNT_REQUIRED);
 119     }
 120
 121     CAmount am(0);
 122     return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
 123 }
 124
 125 unsigned int bitcoinconsensus_version()
 126 {
 127     // Just use the API version for now
 128     return BITCOINCONSENSUS_API_VER;
 129 }