From 5e4236d226309a32842a6928878fd0e1cd5937e7 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 23 Nov 2018 18:02:44 +0100 Subject: tls: in AES-CBC code, do not set key for every record - do it once function old new delta aes_setkey 16 212 +196 tls_handshake 1941 1977 +36 aes_encrypt_1 382 396 +14 xwrite_encrypted 605 604 -1 tls_xread_record 659 656 -3 aes_encrypt_one_block 65 59 -6 aes_cbc_encrypt 172 121 -51 aesgcm_setkey 58 - -58 aes_cbc_decrypt 958 881 -77 KeyExpansion 188 - -188 ------------------------------------------------------------------------------ (add/remove: 0/2 grow/shrink: 3/5 up/down: 246/-384) Total: -138 bytes Signed-off-by: Denys Vlasenko --- networking/tls.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'networking/tls.c') diff --git a/networking/tls.c b/networking/tls.c index 38a965ad6..23622d76e 100644 --- a/networking/tls.c +++ b/networking/tls.c @@ -758,7 +758,7 @@ static void xwrite_encrypted_and_hmac_signed(tls_state_t *tls, unsigned size, un /* Encrypt content+MAC+padding in place */ //optimize key setup aes_cbc_encrypt( - tls->client_write_key, tls->key_size, /* selects 128/256 */ + &tls->aes_decrypt, /* selects 128/256 */ buf - AES_BLOCK_SIZE, /* IV */ buf, size, /* plaintext */ buf /* ciphertext */ @@ -1061,7 +1061,7 @@ static int tls_xread_record(tls_state_t *tls, const char *expected) /* Decrypt content+MAC+padding, moving it over IV in the process */ sz -= AES_BLOCK_SIZE; /* we will overwrite IV now */ aes_cbc_decrypt( - tls->server_write_key, tls->key_size, /* selects 128/256 */ + &tls->aes_decrypt, /* selects 128/256 */ p, /* IV */ p + AES_BLOCK_SIZE, sz, /* ciphertext */ p /* plaintext */ @@ -1934,8 +1934,14 @@ static void send_client_key_exchange(tls_state_t *tls) dump_hex("client_write_IV:%s\n", tls->client_write_IV, tls->IV_size ); - aesgcm_setkey(tls->H, &tls->aes_encrypt, tls->client_write_key, tls->key_size); + aes_setkey(&tls->aes_decrypt, tls->server_write_key, tls->key_size); + aes_setkey(&tls->aes_encrypt, tls->client_write_key, tls->key_size); + { + uint8_t iv[AES_BLOCK_SIZE]; + memset(iv, 0, AES_BLOCK_SIZE); + aes_encrypt_one_block(&tls->aes_encrypt, iv, tls->H); + } } } -- cgit v1.2.3