8 #include <botan/emsa2.h>     9 #include <botan/hash_id.h>    18 SecureVector<byte> emsa2_encoding(
const MemoryRegion<byte>& msg,
    20                                   const MemoryRegion<byte>& empty_hash,
    23    const size_t HASH_SIZE = empty_hash.size();
    25    size_t output_length = (output_bits + 1) / 8;
    27    if(msg.size() != HASH_SIZE)
    28       throw Encoding_Error(
"EMSA2::encoding_of: Bad input length");
    29    if(output_length < HASH_SIZE + 4)
    30       throw Encoding_Error(
"EMSA2::encoding_of: Output length is too small");
    33    for(
size_t j = 0; j != HASH_SIZE; ++j)
    34       if(empty_hash[j] != msg[j])
    37    SecureVector<byte> output(output_length);
    39    output[0] = (empty ? 0x4B : 0x6B);
    40    output[output_length - 3 - HASH_SIZE] = 0xBA;
    41    set_mem(&output[1], output_length - 4 - HASH_SIZE, 0xBB);
    42    output.copy(output_length - (HASH_SIZE + 2), &msg[0], msg.size());
    43    output[output_length-2] = hash_id;
    44    output[output_length-1] = 0xCC;
    54 void EMSA2::update(
const byte input[], 
size_t length)
    56    hash->
update(input, length);
    62 SecureVector<byte> EMSA2::raw_data()
    70 SecureVector<byte> EMSA2::encoding_of(
const MemoryRegion<byte>& msg,
    72                                       RandomNumberGenerator&)
    74    return emsa2_encoding(msg, output_bits, empty_hash, hash_id);
    80 bool EMSA2::verify(
const MemoryRegion<byte>& coded,
    81                    const MemoryRegion<byte>& raw,
    86       return (coded == emsa2_encoding(raw, key_bits,
    87                                       empty_hash, hash_id));
   100    empty_hash = hash->
final();
   102    const std::string hash_name = hash->
name();
 byte ieee1363_hash_id(const std::string &name)
void update(const byte in[], size_t length)
EMSA2(HashFunction *hash)
virtual std::string name() const =0
void set_mem(T *ptr, size_t n, byte val)