diff options
Diffstat (limited to 'src/pluto/demux.c')
| -rw-r--r-- | src/pluto/demux.c | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/src/pluto/demux.c b/src/pluto/demux.c index fef9b98cc..53b44a0f8 100644 --- a/src/pluto/demux.c +++ b/src/pluto/demux.c @@ -1780,9 +1780,17 @@ process_packet(struct msg_digest **mdp) * the last phase 1 block, not the last block sent. */ { - const struct encrypt_desc *e = st->st_oakley.encrypter; + size_t crypter_block_size; + encryption_algorithm_t enc_alg; + crypter_t *crypter; + chunk_t data, iv; + char *new_iv; - if (pbs_left(&md->message_pbs) % e->enc_blocksize != 0) + enc_alg = oakley_to_encryption_algorithm(st->st_oakley.encrypt); + crypter = lib->crypto->create_crypter(lib->crypto, enc_alg, st->st_enc_key.len); + crypter_block_size = crypter->get_block_size(crypter); + + if (pbs_left(&md->message_pbs) % crypter_block_size != 0) { loglog(RC_LOG_SERIOUS, "malformed message: not a multiple of encryption blocksize"); SEND_NOTIFICATION(PAYLOAD_MALFORMED); @@ -1795,6 +1803,8 @@ process_packet(struct msg_digest **mdp) md->raw_packet = chunk_create(md->packet_pbs.start, pbs_room(&md->packet_pbs)); md->raw_packet = chunk_clone(md->raw_packet); + data = chunk_create(md->message_pbs.cur, pbs_left(&md->message_pbs)); + /* Decrypt everything after header */ if (!new_iv_set) { @@ -1803,8 +1813,19 @@ process_packet(struct msg_digest **mdp) st->st_new_iv_len = st->st_iv_len; memcpy(st->st_new_iv, st->st_iv, st->st_new_iv_len); } - crypto_cbc_encrypt(e, FALSE, md->message_pbs.cur, - pbs_left(&md->message_pbs) , st); + + /* form iv by truncation */ + st->st_new_iv_len = crypter_block_size; + iv = chunk_create(st->st_new_iv, st->st_new_iv_len); + new_iv = alloca(crypter_block_size); + memcpy(new_iv, data.ptr + data.len - crypter_block_size, + crypter_block_size); + + crypter->set_key(crypter, st->st_enc_key); + crypter->decrypt(crypter, data, iv, NULL); + crypter->destroy(crypter); + + memcpy(st->st_new_iv, new_iv, crypter_block_size); if (restore_iv) { memcpy(st->st_new_iv, new_iv, new_iv_len); |