diff options
author | lloyd <[email protected]> | 2008-11-08 19:46:52 +0000 |
---|---|---|
committer | lloyd <[email protected]> | 2008-11-08 19:46:52 +0000 |
commit | f1c459725da56fd8ed5766e7779300182fa26bcf (patch) | |
tree | 32295cec92df1155563ae8a535dc695d6800d7f6 /src/block/xtea/xtea.cpp | |
parent | 8dba7b5264403e781bbb86ff61850e4377dca7b9 (diff) |
Split ciphers into block and stream ciphers. Move base class headers
Diffstat (limited to 'src/block/xtea/xtea.cpp')
-rw-r--r-- | src/block/xtea/xtea.cpp | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/src/block/xtea/xtea.cpp b/src/block/xtea/xtea.cpp new file mode 100644 index 000000000..db5c7effc --- /dev/null +++ b/src/block/xtea/xtea.cpp @@ -0,0 +1,78 @@ +/************************************************* +* XTEA Source File * +* (C) 1999-2007 Jack Lloyd * +*************************************************/ + +#include <botan/xtea.h> +#include <botan/loadstor.h> +#include <botan/parsing.h> + +namespace Botan { + +/************************************************* +* XTEA Encryption * +*************************************************/ +void XTEA::enc(const byte in[], byte out[]) const + { + u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1); + + for(u32bit j = 0; j != 32; ++j) + { + L += (((R << 4) ^ (R >> 5)) + R) ^ EK[2*j]; + R += (((L << 4) ^ (L >> 5)) + L) ^ EK[2*j+1]; + } + + store_be(out, L, R); + } + +/************************************************* +* XTEA Decryption * +*************************************************/ +void XTEA::dec(const byte in[], byte out[]) const + { + u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1); + + for(u32bit j = 32; j > 0; --j) + { + R -= (((L << 4) ^ (L >> 5)) + L) ^ EK[2*j - 1]; + L -= (((R << 4) ^ (R >> 5)) + R) ^ EK[2*j - 2]; + } + + store_be(out, L, R); + } + +/************************************************* +* XTEA Key Schedule * +*************************************************/ +void XTEA::key(const byte key[], u32bit) + { + static const u32bit DELTAS[64] = { + 0x00000000, 0x9E3779B9, 0x9E3779B9, 0x3C6EF372, 0x3C6EF372, 0xDAA66D2B, + 0xDAA66D2B, 0x78DDE6E4, 0x78DDE6E4, 0x1715609D, 0x1715609D, 0xB54CDA56, + 0xB54CDA56, 0x5384540F, 0x5384540F, 0xF1BBCDC8, 0xF1BBCDC8, 0x8FF34781, + 0x8FF34781, 0x2E2AC13A, 0x2E2AC13A, 0xCC623AF3, 0xCC623AF3, 0x6A99B4AC, + 0x6A99B4AC, 0x08D12E65, 0x08D12E65, 0xA708A81E, 0xA708A81E, 0x454021D7, + 0x454021D7, 0xE3779B90, 0xE3779B90, 0x81AF1549, 0x81AF1549, 0x1FE68F02, + 0x1FE68F02, 0xBE1E08BB, 0xBE1E08BB, 0x5C558274, 0x5C558274, 0xFA8CFC2D, + 0xFA8CFC2D, 0x98C475E6, 0x98C475E6, 0x36FBEF9F, 0x36FBEF9F, 0xD5336958, + 0xD5336958, 0x736AE311, 0x736AE311, 0x11A25CCA, 0x11A25CCA, 0xAFD9D683, + 0xAFD9D683, 0x4E11503C, 0x4E11503C, 0xEC48C9F5, 0xEC48C9F5, 0x8A8043AE, + 0x8A8043AE, 0x28B7BD67, 0x28B7BD67, 0xC6EF3720 }; + + static const byte KEY_INDEX[64] = { + 0x00, 0x03, 0x01, 0x02, 0x02, 0x01, 0x03, 0x00, 0x00, 0x00, 0x01, 0x03, + 0x02, 0x02, 0x03, 0x01, 0x00, 0x00, 0x01, 0x00, 0x02, 0x03, 0x03, 0x02, + 0x00, 0x01, 0x01, 0x01, 0x02, 0x00, 0x03, 0x03, 0x00, 0x02, 0x01, 0x01, + 0x02, 0x01, 0x03, 0x00, 0x00, 0x03, 0x01, 0x02, 0x02, 0x01, 0x03, 0x01, + 0x00, 0x00, 0x01, 0x03, 0x02, 0x02, 0x03, 0x02, 0x00, 0x01, 0x01, 0x00, + 0x02, 0x03, 0x03, 0x02 }; + + SecureBuffer<u32bit, 4> UK; + for(u32bit j = 0; j != 4; ++j) + UK[j] = load_be<u32bit>(key, j); + + for(u32bit j = 0; j != 64; ++j) + EK[j] = DELTAS[j] + UK[KEY_INDEX[j]]; + } + +} |