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Diffstat (limited to 'src/pubkey.h')
| -rw-r--r-- | src/pubkey.h | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/src/pubkey.h b/src/pubkey.h new file mode 100644 index 0000000000..ccf9673453 --- /dev/null +++ b/src/pubkey.h @@ -0,0 +1,206 @@ +// Copyright (c) 2009-2010 Satoshi Nakamoto +// Copyright (c) 2009-2013 The Bitcoin developers +// Distributed under the MIT/X11 software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#ifndef BITCOIN_PUBKEY_H +#define BITCOIN_PUBKEY_H + +#include "hash.h" +#include "serialize.h" +#include "uint256.h" + +#include <stdexcept> +#include <vector> + +/** + * secp256k1: + * const unsigned int PRIVATE_KEY_SIZE = 279; + * const unsigned int PUBLIC_KEY_SIZE = 65; + * const unsigned int SIGNATURE_SIZE = 72; + * + * see www.keylength.com + * script supports up to 75 for single byte push + */ + +/** A reference to a CKey: the Hash160 of its serialized public key */ +class CKeyID : public uint160 +{ +public: + CKeyID() : uint160(0) {} + CKeyID(const uint160& in) : uint160(in) {} +}; + +/** An encapsulated public key. */ +class CPubKey +{ +private: + + /** + * Just store the serialized data. + * Its length can very cheaply be computed from the first byte. + */ + unsigned char vch[65]; + + //! Compute the length of a pubkey with a given first byte. + unsigned int static GetLen(unsigned char chHeader) + { + if (chHeader == 2 || chHeader == 3) + return 33; + if (chHeader == 4 || chHeader == 6 || chHeader == 7) + return 65; + return 0; + } + + //! Set this key data to be invalid + void Invalidate() + { + vch[0] = 0xFF; + } + +public: + //! Construct an invalid public key. + CPubKey() + { + Invalidate(); + } + + //! Initialize a public key using begin/end iterators to byte data. + template <typename T> + void Set(const T pbegin, const T pend) + { + int len = pend == pbegin ? 0 : GetLen(pbegin[0]); + if (len && len == (pend - pbegin)) + memcpy(vch, (unsigned char*)&pbegin[0], len); + else + Invalidate(); + } + + //! Construct a public key using begin/end iterators to byte data. + template <typename T> + CPubKey(const T pbegin, const T pend) + { + Set(pbegin, pend); + } + + //! Construct a public key from a byte vector. + CPubKey(const std::vector<unsigned char>& vch) + { + Set(vch.begin(), vch.end()); + } + + //! Simple read-only vector-like interface to the pubkey data. + unsigned int size() const { return GetLen(vch[0]); } + const unsigned char* begin() const { return vch; } + const unsigned char* end() const { return vch + size(); } + const unsigned char& operator[](unsigned int pos) const { return vch[pos]; } + + //! Comparator implementation. + friend bool operator==(const CPubKey& a, const CPubKey& b) + { + return a.vch[0] == b.vch[0] && + memcmp(a.vch, b.vch, a.size()) == 0; + } + friend bool operator!=(const CPubKey& a, const CPubKey& b) + { + return !(a == b); + } + friend bool operator<(const CPubKey& a, const CPubKey& b) + { + return a.vch[0] < b.vch[0] || + (a.vch[0] == b.vch[0] && memcmp(a.vch, b.vch, a.size()) < 0); + } + + //! Implement serialization, as if this was a byte vector. + unsigned int GetSerializeSize(int nType, int nVersion) const + { + return size() + 1; + } + template <typename Stream> + void Serialize(Stream& s, int nType, int nVersion) const + { + unsigned int len = size(); + ::WriteCompactSize(s, len); + s.write((char*)vch, len); + } + template <typename Stream> + void Unserialize(Stream& s, int nType, int nVersion) + { + unsigned int len = ::ReadCompactSize(s); + if (len <= 65) { + s.read((char*)vch, len); + } else { + // invalid pubkey, skip available data + char dummy; + while (len--) + s.read(&dummy, 1); + Invalidate(); + } + } + + //! Get the KeyID of this public key (hash of its serialization) + CKeyID GetID() const + { + return CKeyID(Hash160(vch, vch + size())); + } + + //! Get the 256-bit hash of this public key. + uint256 GetHash() const + { + return Hash(vch, vch + size()); + } + + /* + * Check syntactic correctness. + * + * Note that this is consensus critical as CheckSig() calls it! + */ + bool IsValid() const + { + return size() > 0; + } + + //! fully validate whether this is a valid public key (more expensive than IsValid()) + bool IsFullyValid() const; + + //! Check whether this is a compressed public key. + bool IsCompressed() const + { + return size() == 33; + } + + /** + * Verify a DER signature (~72 bytes). + * If this public key is not fully valid, the return value will be false. + */ + bool Verify(const uint256& hash, const std::vector<unsigned char>& vchSig) const; + + //! Recover a public key from a compact signature. + bool RecoverCompact(const uint256& hash, const std::vector<unsigned char>& vchSig); + + //! Turn this public key into an uncompressed public key. + bool Decompress(); + + //! Derive BIP32 child pubkey. + bool Derive(CPubKey& pubkeyChild, unsigned char ccChild[32], unsigned int nChild, const unsigned char cc[32]) const; +}; + +struct CExtPubKey { + unsigned char nDepth; + unsigned char vchFingerprint[4]; + unsigned int nChild; + unsigned char vchChainCode[32]; + CPubKey pubkey; + + friend bool operator==(const CExtPubKey& a, const CExtPubKey& b) + { + return a.nDepth == b.nDepth && memcmp(&a.vchFingerprint[0], &b.vchFingerprint[0], 4) == 0 && a.nChild == b.nChild && + memcmp(&a.vchChainCode[0], &b.vchChainCode[0], 32) == 0 && a.pubkey == b.pubkey; + } + + void Encode(unsigned char code[74]) const; + void Decode(const unsigned char code[74]); + bool Derive(CExtPubKey& out, unsigned int nChild) const; +}; + +#endif // BITCOIN_PUBKEY_H |