| // boost/uuid/sha1.hpp header file ----------------------------------------------// |
| |
| // Copyright 2007 Andy Tompkins. |
| // Distributed under the Boost Software License, Version 1.0. (See |
| // accompanying file LICENSE_1_0.txt or copy at |
| // http://www.boost.org/LICENSE_1_0.txt) |
| |
| // Revision History |
| // 29 May 2007 - Initial Revision |
| // 25 Feb 2008 - moved to namespace boost::uuids::detail |
| |
| // This is a byte oriented implementation |
| // Note: this implementation does not handle message longer than |
| // 2^32 bytes. |
| |
| #ifndef BOOST_UUID_SHA1_H |
| #define BOOST_UUID_SHA1_H |
| |
| #include <boost/static_assert.hpp> |
| #include <cstddef> |
| |
| #ifdef BOOST_NO_STDC_NAMESPACE |
| namespace std { |
| using ::size_t; |
| } // namespace std |
| #endif |
| |
| namespace boost { |
| namespace uuids { |
| namespace detail { |
| |
| BOOST_STATIC_ASSERT(sizeof(unsigned char)*8 == 8); |
| BOOST_STATIC_ASSERT(sizeof(unsigned int)*8 == 32); |
| |
| inline unsigned int left_rotate(unsigned int x, std::size_t n) |
| { |
| return (x<<n) ^ (x>> (32-n)); |
| } |
| |
| class sha1 |
| { |
| public: |
| typedef unsigned int(&digest_type)[5]; |
| public: |
| sha1(); |
| |
| void reset(); |
| |
| void process_byte(unsigned char byte); |
| void process_block(void const* bytes_begin, void const* bytes_end); |
| void process_bytes(void const* buffer, std::size_t byte_count); |
| |
| void get_digest(digest_type digest); |
| |
| private: |
| void process_block(); |
| |
| private: |
| unsigned int h_[5]; |
| |
| unsigned char block_[64]; |
| |
| std::size_t block_byte_index_; |
| std::size_t byte_count_; |
| }; |
| |
| inline sha1::sha1() |
| { |
| reset(); |
| } |
| |
| inline void sha1::reset() |
| { |
| h_[0] = 0x67452301; |
| h_[1] = 0xEFCDAB89; |
| h_[2] = 0x98BADCFE; |
| h_[3] = 0x10325476; |
| h_[4] = 0xC3D2E1F0; |
| |
| block_byte_index_ = 0; |
| byte_count_ = 0; |
| } |
| |
| inline void sha1::process_byte(unsigned char byte) |
| { |
| block_[block_byte_index_++] = byte; |
| ++byte_count_; |
| if (block_byte_index_ == 64) { |
| block_byte_index_ = 0; |
| process_block(); |
| } |
| } |
| |
| inline void sha1::process_block(void const* bytes_begin, void const* bytes_end) |
| { |
| unsigned char const* begin = static_cast<unsigned char const*>(bytes_begin); |
| unsigned char const* end = static_cast<unsigned char const*>(bytes_end); |
| for(; begin != end; ++begin) { |
| process_byte(*begin); |
| } |
| } |
| |
| inline void sha1::process_bytes(void const* buffer, std::size_t byte_count) |
| { |
| unsigned char const* b = static_cast<unsigned char const*>(buffer); |
| process_block(b, b+byte_count); |
| } |
| |
| inline void sha1::process_block() |
| { |
| unsigned int w[80]; |
| for (std::size_t i=0; i<16; ++i) { |
| w[i] = (block_[i*4 + 0] << 24); |
| w[i] |= (block_[i*4 + 1] << 16); |
| w[i] |= (block_[i*4 + 2] << 8); |
| w[i] |= (block_[i*4 + 3]); |
| } |
| for (std::size_t i=16; i<80; ++i) { |
| w[i] = left_rotate((w[i-3] ^ w[i-8] ^ w[i-14] ^ w[i-16]), 1); |
| } |
| |
| unsigned int a = h_[0]; |
| unsigned int b = h_[1]; |
| unsigned int c = h_[2]; |
| unsigned int d = h_[3]; |
| unsigned int e = h_[4]; |
| |
| for (std::size_t i=0; i<80; ++i) { |
| unsigned int f; |
| unsigned int k; |
| |
| if (i<20) { |
| f = (b & c) | (~b & d); |
| k = 0x5A827999; |
| } else if (i<40) { |
| f = b ^ c ^ d; |
| k = 0x6ED9EBA1; |
| } else if (i<60) { |
| f = (b & c) | (b & d) | (c & d); |
| k = 0x8F1BBCDC; |
| } else { |
| f = b ^ c ^ d; |
| k = 0xCA62C1D6; |
| } |
| |
| unsigned temp = left_rotate(a, 5) + f + e + k + w[i]; |
| e = d; |
| d = c; |
| c = left_rotate(b, 30); |
| b = a; |
| a = temp; |
| } |
| |
| h_[0] += a; |
| h_[1] += b; |
| h_[2] += c; |
| h_[3] += d; |
| h_[4] += e; |
| } |
| |
| inline void sha1::get_digest(digest_type digest) |
| { |
| std::size_t bit_count = byte_count_*8; |
| |
| // append the bit '1' to the message |
| process_byte(0x80); |
| |
| // append k bits '0', where k is the minimum number >= 0 |
| // such that the resulting message length is congruent to 56 (mod 64) |
| // check if there is enough space for padding and bit_count |
| if (block_byte_index_ > 56) { |
| // finish this block |
| while (block_byte_index_ != 0) { |
| process_byte(0); |
| } |
| |
| // one more block |
| while (block_byte_index_ < 56) { |
| process_byte(0); |
| } |
| } else { |
| while (block_byte_index_ < 56) { |
| process_byte(0); |
| } |
| } |
| |
| // append length of message (before pre-processing) |
| // as a 64-bit big-endian integer |
| process_byte(0); |
| process_byte(0); |
| process_byte(0); |
| process_byte(0); |
| process_byte( static_cast<unsigned char>((bit_count>>24) & 0xFF)); |
| process_byte( static_cast<unsigned char>((bit_count>>16) & 0xFF)); |
| process_byte( static_cast<unsigned char>((bit_count>>8 ) & 0xFF)); |
| process_byte( static_cast<unsigned char>((bit_count) & 0xFF)); |
| |
| // get final digest |
| digest[0] = h_[0]; |
| digest[1] = h_[1]; |
| digest[2] = h_[2]; |
| digest[3] = h_[3]; |
| digest[4] = h_[4]; |
| } |
| |
| }}} // namespace boost::uuids::detail |
| |
| #endif |