diff options
Diffstat (limited to 'cypher.cpp')
| -rw-r--r-- | cypher.cpp | 40 |
1 files changed, 11 insertions, 29 deletions
@@ -35,36 +35,21 @@ #include <gcrypt.h> #include "cypher.h" -#include "keyDerivation.h" #include "mpi.h" #include "log.h" -void Cypher::cypher(Buffer& buf, seq_nr_t seq_nr, sender_id_t sender_id) -{ - Buffer stream = getBitStream(buf.getLength(), seq_nr, sender_id); - exor(buf, stream); -} - -void Cypher::exor(Buffer& buf, const Buffer& bit_stream) +void NullCypher::cypher(Buffer& out, Buffer& in, u_int32_t length, seq_nr_t seq_nr, sender_id_t sender_id) { try { - for(u_int32_t i; i<buf.getLength(); ++i) - buf[i] ^= bit_stream[i]; + for(u_int32_t i; i<length; ++i) + out[i] = in[i]; } catch(std::out_of_range& o) {} } -Buffer NullCypher::getBitStream(u_int32_t length, seq_nr_t seq_nr, sender_id_t sender_id) -{ - Buffer buf(length); - for(u_int32_t i; i<length; ++i) - buf[i] = 0; - return buf; -} - const char* AesIcmCypher::MIN_GCRYPT_VERSION = "1.2.3"; AesIcmCypher::AesIcmCypher() : salt_(Buffer(14)) @@ -127,18 +112,17 @@ void AesIcmCypher::setSalt(Buffer salt) salt_ = salt; } -Buffer AesIcmCypher::getBitStream(u_int32_t length, seq_nr_t seq_nr, sender_id_t sender_id) +void AesIcmCypher::cypher(Buffer& out, Buffer& in, u_int32_t length, seq_nr_t seq_nr, sender_id_t sender_id) { gcry_error_t err; - Buffer buf(length); - - // // set IV + // set the IV + //========================================================================== // // where the 128-bit integer value IV SHALL be defined by the SSRC, the // // SRTP packet index i, and the SRTP session salting key k_s, as below. // // // // IV = (k_s * 2^16) XOR (SSRC * 2^64) XOR (i * 2^16) - // // sizeof(k_s) = 112 bit, random + // // sizeof(k_s) = 112 bit, random Mpi iv(128); Mpi salt = Mpi(salt_.getBuf(), salt_.getLength()); @@ -152,21 +136,19 @@ Buffer AesIcmCypher::getBitStream(u_int32_t length, seq_nr_t seq_nr, sender_id_t delete[] iv_buf; if( err ) { cLog.msg(Log::PRIO_ERR) << "AesIcmCypher: Failed to set cipher IV: " << gpg_strerror( err ); - return Buffer(0); + return; } err = gcry_cipher_reset( cipher_ ); if( err ) { cLog.msg(Log::PRIO_ERR) << "AesIcmCypher: Failed to reset cipher: " << gpg_strerror( err ); - return Buffer(0); + return; } - err = gcry_cipher_encrypt( cipher_, buf, buf.getLength(), 0, 0 ); + err = gcry_cipher_encrypt( cipher_, out, out.getLength(), in, in.getLength() ); if( err ) { cLog.msg(Log::PRIO_ERR) << "AesIcmCypher: Failed to generate cipher bitstream: " << gpg_strerror( err ); - return Buffer(0); + return; } - - return buf; } |