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/block/rc5 | |
parent | 9efa3be92442afb3d0b69890a36c7f122df18eda (diff) |
Move lib into src
Diffstat (limited to 'src/lib/block/rc5')
-rw-r--r-- | src/lib/block/rc5/info.txt | 1 | ||||
-rw-r--r-- | src/lib/block/rc5/rc5.cpp | 135 | ||||
-rw-r--r-- | src/lib/block/rc5/rc5.h | 42 |
3 files changed, 178 insertions, 0 deletions
diff --git a/src/lib/block/rc5/info.txt b/src/lib/block/rc5/info.txt new file mode 100644 index 000000000..2c2c613ba --- /dev/null +++ b/src/lib/block/rc5/info.txt @@ -0,0 +1 @@ +define RC5 20131128 diff --git a/src/lib/block/rc5/rc5.cpp b/src/lib/block/rc5/rc5.cpp new file mode 100644 index 000000000..f370e6cfb --- /dev/null +++ b/src/lib/block/rc5/rc5.cpp @@ -0,0 +1,135 @@ +/* +* RC5 +* (C) 1999-2007 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#include <botan/rc5.h> +#include <botan/loadstor.h> +#include <botan/rotate.h> +#include <botan/parsing.h> +#include <algorithm> + +namespace Botan { + +/* +* RC5 Encryption +*/ +void RC5::encrypt_n(const byte in[], byte out[], size_t blocks) const + { + for(size_t i = 0; i != blocks; ++i) + { + u32bit A = load_le<u32bit>(in, 0); + u32bit B = load_le<u32bit>(in, 1); + + A += S[0]; B += S[1]; + for(size_t j = 0; j != rounds; j += 4) + { + A = rotate_left(A ^ B, B % 32) + S[2*j+2]; + B = rotate_left(B ^ A, A % 32) + S[2*j+3]; + + A = rotate_left(A ^ B, B % 32) + S[2*j+4]; + B = rotate_left(B ^ A, A % 32) + S[2*j+5]; + + A = rotate_left(A ^ B, B % 32) + S[2*j+6]; + B = rotate_left(B ^ A, A % 32) + S[2*j+7]; + + A = rotate_left(A ^ B, B % 32) + S[2*j+8]; + B = rotate_left(B ^ A, A % 32) + S[2*j+9]; + } + + store_le(out, A, B); + + in += BLOCK_SIZE; + out += BLOCK_SIZE; + } + } + +/* +* RC5 Decryption +*/ +void RC5::decrypt_n(const byte in[], byte out[], size_t blocks) const + { + for(size_t i = 0; i != blocks; ++i) + { + u32bit A = load_le<u32bit>(in, 0); + u32bit B = load_le<u32bit>(in, 1); + + for(size_t j = rounds; j != 0; j -= 4) + { + B = rotate_right(B - S[2*j+1], A % 32) ^ A; + A = rotate_right(A - S[2*j ], B % 32) ^ B; + + B = rotate_right(B - S[2*j-1], A % 32) ^ A; + A = rotate_right(A - S[2*j-2], B % 32) ^ B; + + B = rotate_right(B - S[2*j-3], A % 32) ^ A; + A = rotate_right(A - S[2*j-4], B % 32) ^ B; + + B = rotate_right(B - S[2*j-5], A % 32) ^ A; + A = rotate_right(A - S[2*j-6], B % 32) ^ B; + } + B -= S[1]; A -= S[0]; + + store_le(out, A, B); + + in += BLOCK_SIZE; + out += BLOCK_SIZE; + } + } + +/* +* RC5 Key Schedule +*/ +void RC5::key_schedule(const byte key[], size_t length) + { + S.resize(2*rounds + 2); + + const size_t WORD_KEYLENGTH = (((length - 1) / 4) + 1); + const size_t MIX_ROUNDS = 3 * std::max(WORD_KEYLENGTH, S.size()); + + S[0] = 0xB7E15163; + for(size_t i = 1; i != S.size(); ++i) + S[i] = S[i-1] + 0x9E3779B9; + + secure_vector<u32bit> K(8); + + for(s32bit i = length-1; i >= 0; --i) + K[i/4] = (K[i/4] << 8) + key[i]; + + u32bit A = 0, B = 0; + + for(size_t i = 0; i != MIX_ROUNDS; ++i) + { + A = rotate_left(S[i % S.size()] + A + B, 3); + B = rotate_left(K[i % WORD_KEYLENGTH] + A + B, (A + B) % 32); + S[i % S.size()] = A; + K[i % WORD_KEYLENGTH] = B; + } + } + +void RC5::clear() + { + zap(S); + } + +/* +* Return the name of this type +*/ +std::string RC5::name() const + { + return "RC5(" + std::to_string(rounds) + ")"; + } + +/* +* RC5 Constructor +*/ +RC5::RC5(size_t r) : rounds(r) + { + if(rounds < 8 || rounds > 32 || (rounds % 4 != 0)) + throw Invalid_Argument("RC5: Invalid number of rounds " + + std::to_string(rounds)); + } + +} diff --git a/src/lib/block/rc5/rc5.h b/src/lib/block/rc5/rc5.h new file mode 100644 index 000000000..9055974e5 --- /dev/null +++ b/src/lib/block/rc5/rc5.h @@ -0,0 +1,42 @@ +/* +* RC5 +* (C) 1999-2007 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#ifndef BOTAN_RC5_H__ +#define BOTAN_RC5_H__ + +#include <botan/block_cipher.h> + +namespace Botan { + +/** +* RC5 +*/ +class BOTAN_DLL RC5 : public Block_Cipher_Fixed_Params<8, 1, 32> + { + public: + void encrypt_n(const byte in[], byte out[], size_t blocks) const; + void decrypt_n(const byte in[], byte out[], size_t blocks) const; + + void clear(); + std::string name() const; + BlockCipher* clone() const { return new RC5(rounds); } + + /** + * @param rounds the number of RC5 rounds to run. Must be between + * 8 and 32 and a multiple of 4. + */ + RC5(size_t rounds); + private: + void key_schedule(const byte[], size_t); + + size_t rounds; + secure_vector<u32bit> S; + }; + +} + +#endif |