diff options
author | lloyd <[email protected]> | 2014-01-10 03:41:59 +0000 |
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committer | lloyd <[email protected]> | 2014-01-10 03:41:59 +0000 |
commit | 6894dca64c04936d07048c0e8cbf7e25858548c3 (patch) | |
tree | 5d572bfde9fe667dab14e3f04b5285a85d8acd95 /src/lib/utils/xor_buf.h | |
parent | 9efa3be92442afb3d0b69890a36c7f122df18eda (diff) |
Move lib into src
Diffstat (limited to 'src/lib/utils/xor_buf.h')
-rw-r--r-- | src/lib/utils/xor_buf.h | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/src/lib/utils/xor_buf.h b/src/lib/utils/xor_buf.h new file mode 100644 index 000000000..5773a619c --- /dev/null +++ b/src/lib/utils/xor_buf.h @@ -0,0 +1,113 @@ +/* +* XOR operations +* (C) 1999-2008 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#ifndef BOTAN_XOR_BUF_H__ +#define BOTAN_XOR_BUF_H__ + +#include <botan/types.h> +#include <vector> + +namespace Botan { + +/** +* XOR arrays. Postcondition out[i] = in[i] ^ out[i] forall i = 0...length +* @param out the input/output buffer +* @param in the read-only input buffer +* @param length the length of the buffers +*/ +inline void xor_buf(byte out[], const byte in[], size_t length) + { + while(length >= 8) + { +#if BOTAN_TARGET_UNALIGNED_MEMORY_ACCESS_OK + *reinterpret_cast<u64bit*>(out) ^= *reinterpret_cast<const u64bit*>(in); +#else + out[0] ^= in[0]; out[1] ^= in[1]; + out[2] ^= in[2]; out[3] ^= in[3]; + out[4] ^= in[4]; out[5] ^= in[5]; + out[6] ^= in[6]; out[7] ^= in[7]; +#endif + + out += 8; in += 8; length -= 8; + } + + for(size_t i = 0; i != length; ++i) + out[i] ^= in[i]; + } + +/** +* XOR arrays. Postcondition out[i] = in[i] ^ in2[i] forall i = 0...length +* @param out the output buffer +* @param in the first input buffer +* @param in2 the second output buffer +* @param length the length of the three buffers +*/ +inline void xor_buf(byte out[], + const byte in[], + const byte in2[], + size_t length) + { + while(length >= 8) + { +#if BOTAN_TARGET_UNALIGNED_MEMORY_ACCESS_OK + *reinterpret_cast<u64bit*>(out) = + *reinterpret_cast<const u64bit*>(in) ^ + *reinterpret_cast<const u64bit*>(in2); +#else + out[0] = in[0] ^ in2[0]; out[1] = in[1] ^ in2[1]; + out[2] = in[2] ^ in2[2]; out[3] = in[3] ^ in2[3]; + out[4] = in[4] ^ in2[4]; out[5] = in[5] ^ in2[5]; + out[6] = in[6] ^ in2[6]; out[7] = in[7] ^ in2[7]; +#endif + + in += 8; in2 += 8; out += 8; length -= 8; + } + + for(size_t i = 0; i != length; ++i) + out[i] = in[i] ^ in2[i]; + } + +template<typename Alloc, typename Alloc2> +void xor_buf(std::vector<byte, Alloc>& out, + const std::vector<byte, Alloc2>& in, + size_t n) + { + xor_buf(&out[0], &in[0], n); + } + +template<typename Alloc> +void xor_buf(std::vector<byte, Alloc>& out, + const byte* in, + size_t n) + { + xor_buf(&out[0], in, n); + } + +template<typename Alloc, typename Alloc2> +void xor_buf(std::vector<byte, Alloc>& out, + const byte* in, + const std::vector<byte, Alloc2>& in2, + size_t n) + { + xor_buf(&out[0], &in[0], &in2[0], n); + } + +template<typename T, typename Alloc, typename Alloc2> +std::vector<T, Alloc>& +operator^=(std::vector<T, Alloc>& out, + const std::vector<T, Alloc2>& in) + { + if(out.size() < in.size()) + out.resize(in.size()); + + xor_buf(&out[0], &in[0], in.size()); + return out; + } + +} + +#endif |