diff options
Diffstat (limited to 'src/block/aes/aes.cpp')
| -rw-r--r-- | src/block/aes/aes.cpp | 126 |
1 files changed, 88 insertions, 38 deletions
diff --git a/src/block/aes/aes.cpp b/src/block/aes/aes.cpp index b317fa735..f149a0ac0 100644 --- a/src/block/aes/aes.cpp +++ b/src/block/aes/aes.cpp @@ -1,6 +1,6 @@ /* * AES -* (C) 1999-2009 Jack Lloyd +* (C) 1999-2010 Jack Lloyd * * Distributed under the terms of the Botan license */ @@ -410,13 +410,16 @@ const u32bit TD[1024] = { 0x3C498B28, 0x0D9541FF, 0xA8017139, 0x0CB3DE08, 0xB4E49CD8, 0x56C19064, 0xCB84617B, 0x32B670D5, 0x6C5C7448, 0xB85742D0 }; -} - /* * AES Encryption */ -void AES::encrypt_n(const byte in[], byte out[], size_t blocks) const +void aes_encrypt_n(const byte in[], byte out[], + size_t blocks, + const MemoryRegion<u32bit>& EK, + const MemoryRegion<byte>& ME) { + const size_t BLOCK_SIZE = 16; + const u32bit* TE0 = TE; const u32bit* TE1 = TE + 256; const u32bit* TE2 = TE + 512; @@ -522,8 +525,12 @@ void AES::encrypt_n(const byte in[], byte out[], size_t blocks) const /* * AES Decryption */ -void AES::decrypt_n(const byte in[], byte out[], size_t blocks) const +void aes_decrypt_n(const byte in[], byte out[], size_t blocks, + const MemoryRegion<u32bit>& DK, + const MemoryRegion<byte>& MD) { + const size_t BLOCK_SIZE = 16; + const u32bit* TD0 = TD; const u32bit* TD1 = TD + 256; const u32bit* TD2 = TD + 512; @@ -599,18 +606,19 @@ void AES::decrypt_n(const byte in[], byte out[], size_t blocks) const } } -/* -* AES Key Schedule -*/ -void AES::key_schedule(const byte key[], size_t length) +void aes_key_schedule(const byte key[], size_t length, + MemoryRegion<u32bit>& EK, + MemoryRegion<u32bit>& DK, + MemoryRegion<byte>& ME, + MemoryRegion<byte>& MD) { static const u32bit RC[10] = { - 0x01000000, 0x02000000, 0x04000000, 0x08000000, 0x10000000, 0x20000000, - 0x40000000, 0x80000000, 0x1B000000, 0x36000000 }; + 0x01000000, 0x02000000, 0x04000000, 0x08000000, 0x10000000, + 0x20000000, 0x40000000, 0x80000000, 0x1B000000, 0x36000000 }; const u32bit rounds = (length / 4) + 6; - SecureVector<u32bit> XEK(64), XDK(64); + SecureVector<u32bit> XEK(length + 32), XDK(length + 32); const size_t X = length / 4; for(size_t i = 0; i != X; ++i) @@ -618,13 +626,23 @@ void AES::key_schedule(const byte key[], size_t length) for(size_t i = X; i < 4*(rounds+1); i += X) { - XEK[i] = XEK[i-X] ^ S(rotate_left(XEK[i-1], 8)) ^ RC[(i-X)/X]; + XEK[i] = XEK[i-X] ^ RC[(i-X)/X] ^ + make_u32bit(SE[get_byte(1, XEK[i-1])], + SE[get_byte(2, XEK[i-1])], + SE[get_byte(3, XEK[i-1])], + SE[get_byte(0, XEK[i-1])]); + for(size_t j = 1; j != X; ++j) { + XEK[i+j] = XEK[i+j-X]; + if(X == 8 && j == 4) - XEK[i+j] = XEK[i+j-X] ^ S(XEK[i+j-1]); + XEK[i+j] ^= make_u32bit(SE[get_byte(0, XEK[i+j-1])], + SE[get_byte(1, XEK[i+j-1])], + SE[get_byte(2, XEK[i+j-1])], + SE[get_byte(3, XEK[i+j-1])]); else - XEK[i+j] = XEK[i+j-X] ^ XEK[i+j-1]; + XEK[i+j] ^= XEK[i+j-1]; } } @@ -652,38 +670,70 @@ void AES::key_schedule(const byte key[], size_t length) DK.set(&XDK[0], length + 24); } -/* -* AES Byte Substitution -*/ -u32bit AES::S(u32bit input) +} + +void AES_128::encrypt_n(const byte in[], byte out[], size_t blocks) const { - return make_u32bit(SE[get_byte(0, input)], SE[get_byte(1, input)], - SE[get_byte(2, input)], SE[get_byte(3, input)]); + aes_encrypt_n(in, out, blocks, EK, ME); } -/* -* AES Constructor -*/ -AES::AES() : BlockCipher_Fixed_Block_Size(16, 32, 8), - EK(0), ME(16), DK(0), MD(16) +void AES_128::decrypt_n(const byte in[], byte out[], size_t blocks) const { + aes_decrypt_n(in, out, blocks, DK, MD); } -/* -* AES Constructor -*/ -AES::AES(size_t key_size) : BlockCipher_Fixed_Block_Size(key_size), - EK(key_size+24), ME(16), - DK(key_size+24), MD(16) +void AES_128::key_schedule(const byte key[], size_t length) { - if(key_size != 16 && key_size != 24 && key_size != 32) - throw Invalid_Key_Length(name(), key_size); + aes_key_schedule(key, length, EK, DK, ME, MD); } -/* -* Clear memory of sensitive data -*/ -void AES::clear() +void AES_128::clear() + { + zeroise(EK); + zeroise(DK); + zeroise(ME); + zeroise(MD); + } + +void AES_192::encrypt_n(const byte in[], byte out[], size_t blocks) const + { + aes_encrypt_n(in, out, blocks, EK, ME); + } + +void AES_192::decrypt_n(const byte in[], byte out[], size_t blocks) const + { + aes_decrypt_n(in, out, blocks, DK, MD); + } + +void AES_192::key_schedule(const byte key[], size_t length) + { + aes_key_schedule(key, length, EK, DK, ME, MD); + } + +void AES_192::clear() + { + zeroise(EK); + zeroise(DK); + zeroise(ME); + zeroise(MD); + } + +void AES_256::encrypt_n(const byte in[], byte out[], size_t blocks) const + { + aes_encrypt_n(in, out, blocks, EK, ME); + } + +void AES_256::decrypt_n(const byte in[], byte out[], size_t blocks) const + { + aes_decrypt_n(in, out, blocks, DK, MD); + } + +void AES_256::key_schedule(const byte key[], size_t length) + { + aes_key_schedule(key, length, EK, DK, ME, MD); + } + +void AES_256::clear() { zeroise(EK); zeroise(DK); |