diff options
Diffstat (limited to 'botan/src/mac/cbc_mac/cbc_mac.cpp')
-rw-r--r-- | botan/src/mac/cbc_mac/cbc_mac.cpp | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/botan/src/mac/cbc_mac/cbc_mac.cpp b/botan/src/mac/cbc_mac/cbc_mac.cpp new file mode 100644 index 0000000..f5d9e15 --- /dev/null +++ b/botan/src/mac/cbc_mac/cbc_mac.cpp @@ -0,0 +1,109 @@ +/* +* CBC-MAC +* (C) 1999-2007 Jack Lloyd +* +* Distributed under the terms of the Botan license +*/ + +#include <botan/cbc_mac.h> +#include <botan/xor_buf.h> +#include <algorithm> + +namespace Botan { + +/* +* Update an CBC-MAC Calculation +*/ +void CBC_MAC::add_data(const byte input[], u32bit length) + { + u32bit xored = std::min(OUTPUT_LENGTH - position, length); + xor_buf(state + position, input, xored); + position += xored; + + if(position < OUTPUT_LENGTH) + return; + + e->encrypt(state); + input += xored; + length -= xored; + while(length >= OUTPUT_LENGTH) + { + xor_buf(state, input, OUTPUT_LENGTH); + e->encrypt(state); + input += OUTPUT_LENGTH; + length -= OUTPUT_LENGTH; + } + + xor_buf(state, input, length); + position = length; + } + +/* +* Finalize an CBC-MAC Calculation +*/ +void CBC_MAC::final_result(byte mac[]) + { + if(position) + e->encrypt(state); + + copy_mem(mac, state.begin(), state.size()); + state.clear(); + position = 0; + } + +/* +* CBC-MAC Key Schedule +*/ +void CBC_MAC::key_schedule(const byte key[], u32bit length) + { + e->set_key(key, length); + } + +/* +* Clear memory of sensitive data +*/ +void CBC_MAC::clear() throw() + { + e->clear(); + state.clear(); + position = 0; + } + +/* +* Return the name of this type +*/ +std::string CBC_MAC::name() const + { + return "CBC-MAC(" + e->name() + ")"; + } + +/* +* Return a clone of this object +*/ +MessageAuthenticationCode* CBC_MAC::clone() const + { + return new CBC_MAC(e->clone()); + } + +/* +* CBC-MAC Constructor +*/ +CBC_MAC::CBC_MAC(BlockCipher* e_in) : + MessageAuthenticationCode(e_in->BLOCK_SIZE, + e_in->MINIMUM_KEYLENGTH, + e_in->MAXIMUM_KEYLENGTH, + e_in->KEYLENGTH_MULTIPLE), + e(e_in), state(e->BLOCK_SIZE) + { + position = 0; + } + +/* +* CBC-MAC Destructor +*/ +CBC_MAC::~CBC_MAC() + { + delete e; + } + +} |