Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2014 The Bitcoin developers
       3             : // Copyright (c) 2015-2021 The PIVX Core developers
       4             : // Distributed under the MIT software license, see the accompanying
       5             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       6             : 
       7             : #ifndef PIVX_KEY_H
       8             : #define PIVX_KEY_H
       9             : 
      10             : #include "serialize.h"
      11             : #include "support/allocators/secure.h"
      12             : #include "uint256.h"
      13             : #include "pubkey.h"
      14             : 
      15             : #include <stdexcept>
      16             : #include <vector>
      17             : 
      18             : class CPubKey;
      19             : 
      20             : struct CExtPubKey;
      21             : 
      22             : /**
      23             :  * CPrivKey is a serialized private key, with all parameters included
      24             :  * (PRIVATE_KEY_SIZE bytes)
      25             :  */
      26             : typedef std::vector<unsigned char, secure_allocator<unsigned char> > CPrivKey;
      27             : 
      28             : /** An encapsulated private key. */
      29    11436920 : class CKey
      30             : {
      31             : public:
      32             :     /**
      33             :      * secp256k1:
      34             :      */
      35             :     static const unsigned int PRIVATE_KEY_SIZE            = 279;
      36             :     static const unsigned int COMPRESSED_PRIVATE_KEY_SIZE = 214;
      37             :     /**
      38             :      * see www.keylength.com
      39             :      * script supports up to 75 for single byte push
      40             :      */
      41             :     static_assert(
      42             :         PRIVATE_KEY_SIZE >= COMPRESSED_PRIVATE_KEY_SIZE,
      43             :         "COMPRESSED_PRIVATE_KEY_SIZE is larger than PRIVATE_KEY_SIZE");
      44             : 
      45             : private:
      46             :     //! Whether this private key is valid. We check for correctness when modifying the key
      47             :     //! data, so fValid should always correspond to the actual state.
      48             :     bool fValid;
      49             : 
      50             :     //! Whether the public key corresponding to this private key is (to be) compressed.
      51             :     bool fCompressed;
      52             : 
      53             :     //! The actual byte data
      54             :     std::vector<unsigned char, secure_allocator<unsigned char> > keydata;
      55             : 
      56             :     //! Check whether the 32-byte array pointed to be vch is valid keydata.
      57             :     bool static Check(const unsigned char* vch);
      58             : 
      59             : public:
      60             :     //! Construct an invalid private key.
      61     3898296 :     CKey() : fValid(false), fCompressed(false)
      62             :     {
      63             :         // Important: vch must be 32 bytes in length to not break serialization
      64     3898296 :         keydata.resize(32);
      65     3898296 :     }
      66             : 
      67          14 :     friend bool operator==(const CKey& a, const CKey& b)
      68             :     {
      69          28 :         return a.fCompressed == b.fCompressed &&
      70          28 :             a.size() == b.size() &&
      71          28 :             memcmp(a.keydata.data(), b.keydata.data(), a.size()) == 0;
      72             :     }
      73             : 
      74             :     //! Initialize using begin and end iterators to byte data.
      75             :     template <typename T>
      76       15784 :     void Set(const T pbegin, const T pend, bool fCompressedIn)
      77             :     {
      78       15784 :         if (size_t(pend - pbegin) != keydata.size()) {
      79           0 :             fValid = false;
      80       15784 :         } else if (Check(&pbegin[0])) {
      81       15784 :             memcpy(keydata.data(), (unsigned char*)&pbegin[0], keydata.size());
      82       15784 :             fValid = true;
      83       15784 :             fCompressed = fCompressedIn;
      84             :         } else {
      85           0 :             fValid = false;
      86             :         }
      87       15784 : }
      88             : 
      89             :     //! Simple read-only vector-like interface.
      90       90954 :     unsigned int size() const { return (fValid ? keydata.size() : 0); }
      91     4032353 :     const unsigned char* begin() const { return keydata.data(); }
      92        7614 :     const unsigned char* end() const { return keydata.data() + size(); }
      93             : 
      94             :     //! Check whether this private key is valid.
      95       89104 :     bool IsValid() const { return fValid; }
      96             : 
      97             :     //! Check whether the public key corresponding to this private key is (to be) compressed.
      98       86660 :     bool IsCompressed() const { return fCompressed; }
      99             : 
     100             :     //! Generate a new private key using a cryptographic PRNG.
     101             :     void MakeNewKey(bool fCompressed);
     102             : 
     103             :     uint256 GetPrivKey_256();
     104             : 
     105             :     /**
     106             :      * Convert the private key to a CPrivKey (serialized secp256k1 private key data).
     107             :      * This is expensive.
     108             :      */
     109             :     CPrivKey GetPrivKey() const;
     110             : 
     111             :     /**
     112             :      * Compute the public key from a private key.
     113             :      * This is expensive.
     114             :      */
     115             :     CPubKey GetPubKey() const;
     116             : 
     117             :     /**
     118             :      * Create a DER-serialized signature.
     119             :      * The test_case parameter tweaks the deterministic nonce.
     120             :      */
     121             :     bool Sign(const uint256& hash, std::vector<unsigned char>& vchSig, uint32_t test_case = 0) const;
     122             : 
     123             :     /**
     124             :      * Create a compact signature (65 bytes), which allows reconstructing the used public key.
     125             :      * The format is one header byte, followed by two times 32 bytes for the serialized r and s values.
     126             :      * The header byte: 0x1B = first key with even y, 0x1C = first key with odd y,
     127             :      *                  0x1D = second key with even y, 0x1E = second key with odd y,
     128             :      *                  add 0x04 for compressed keys.
     129             :      */
     130             :     bool SignCompact(const uint256& hash, std::vector<unsigned char>& vchSig) const;
     131             : 
     132             :     //! Derive BIP32 child key.
     133             :     bool Derive(CKey& keyChild, ChainCode &ccChild, unsigned int nChild, const ChainCode& cc) const;
     134             : 
     135             :     /**
     136             :      * Verify thoroughly whether a private key and a public key match.
     137             :      * This is done using a different mechanism than just regenerating it.
     138             :      */
     139             :     bool VerifyPubKey(const CPubKey& vchPubKey) const;
     140             : 
     141             :     //! Load private key and check that public key matches.
     142             :     bool Load(const CPrivKey& privkey, const CPubKey& vchPubKey, bool fSkipCheck);
     143             : 
     144             :     //! Check whether an element of a signature (r or s) is valid.
     145             :     static bool CheckSignatureElement(const unsigned char* vch, int len, bool half);
     146             : };
     147             : 
     148      197380 : struct CExtKey {
     149             :     unsigned char nDepth;
     150             :     unsigned char vchFingerprint[4];
     151             :     unsigned int nChild;
     152             :     ChainCode chaincode;
     153             :     CKey key;
     154             : 
     155          14 :     friend bool operator==(const CExtKey& a, const CExtKey& b)
     156             :     {
     157          28 :         return a.nDepth == b.nDepth &&
     158          14 :             memcmp(&a.vchFingerprint[0], &b.vchFingerprint[0], sizeof(vchFingerprint)) == 0 &&
     159          14 :             a.nChild == b.nChild &&
     160          28 :             a.chaincode == b.chaincode &&
     161          14 :             a.key == b.key;
     162             :     }
     163             : 
     164             :     void Encode(unsigned char code[BIP32_EXTKEY_SIZE]) const;
     165             :     void Decode(const unsigned char code[BIP32_EXTKEY_SIZE]);
     166             :     bool Derive(CExtKey& out, unsigned int nChild) const;
     167             :     CExtPubKey Neuter() const;
     168             :     void SetSeed(const unsigned char* seed, unsigned int nSeedLen);
     169             : };
     170             : 
     171             : /** Initialize the elliptic curve support. May not be called twice without calling ECC_Stop first. */
     172             : void ECC_Start(void);
     173             : 
     174             : /** Deinitialize the elliptic curve support. No-op if ECC_Start wasn't called first. */
     175             : void ECC_Stop(void);
     176             : 
     177             : /** Check that required EC support is available at runtime. */
     178             : bool ECC_InitSanityCheck(void);
     179             : 
     180             : #endif // PIVX_KEY_H