1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2018 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/namecoinconsensus.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:
TxInputStream(int nTypeIn,int nVersionIn,const unsigned char * txTo,size_t txToLen)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 
read(char * pch,size_t nSize)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>
operator >>(T && obj)43     TxInputStream& operator>>(T&& obj)
44     {
45         ::Unserialize(*this, obj);
46         return *this;
47     }
48 
GetVersion() const49     int GetVersion() const { return m_version; }
GetType() const50     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 
set_error(namecoinconsensus_error * ret,namecoinconsensus_error serror)58 inline int set_error(namecoinconsensus_error* ret, namecoinconsensus_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. */
verify_flags(unsigned int flags)74 static bool verify_flags(unsigned int flags)
75 {
76     return (flags & ~(namecoinconsensus_SCRIPT_FLAGS_VERIFY_ALL)) == 0;
77 }
78 
verify_script(const unsigned char * scriptPubKey,unsigned int scriptPubKeyLen,CAmount amount,const unsigned char * txTo,unsigned int txToLen,unsigned int nIn,unsigned int flags,namecoinconsensus_error * err)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, namecoinconsensus_error* err)
82 {
83     if (!verify_flags(flags)) {
84         return set_error(err, namecoinconsensus_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, namecoinconsensus_ERR_TX_INDEX);
91         if (GetSerializeSize(tx, PROTOCOL_VERSION) != txToLen)
92             return set_error(err, namecoinconsensus_ERR_TX_SIZE_MISMATCH);
93 
94         // Regardless of the verification result, the tx did not error.
95         set_error(err, namecoinconsensus_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, namecoinconsensus_ERR_TX_DESERIALIZE); // Error deserializing
101     }
102 }
103 
namecoinconsensus_verify_script_with_amount(const unsigned char * scriptPubKey,unsigned int scriptPubKeyLen,int64_t amount,const unsigned char * txTo,unsigned int txToLen,unsigned int nIn,unsigned int flags,namecoinconsensus_error * err)104 int namecoinconsensus_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, namecoinconsensus_error* err)
107 {
108     CAmount am(amount);
109     return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
110 }
111 
112 
namecoinconsensus_verify_script(const unsigned char * scriptPubKey,unsigned int scriptPubKeyLen,const unsigned char * txTo,unsigned int txToLen,unsigned int nIn,unsigned int flags,namecoinconsensus_error * err)113 int namecoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
114                                    const unsigned char *txTo        , unsigned int txToLen,
115                                    unsigned int nIn, unsigned int flags, namecoinconsensus_error* err)
116 {
117     if (flags & namecoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS) {
118         return set_error(err, namecoinconsensus_ERR_AMOUNT_REQUIRED);
119     }
120 
121     CAmount am(0);
122     return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
123 }
124 
namecoinconsensus_version()125 unsigned int namecoinconsensus_version()
126 {
127     // Just use the API version for now
128     return NAMECOINCONSENSUS_API_VER;
129 }
130