Remove begin_handshake and allocate init_buf lazily. For TLS 1.3, we will need to process more complex post-handshake messages. It is simplest if we use the same mechanism. In preparation, allow ssl3_get_message to be called at any point. Note that this stops reserving SSL3_RT_MAX_PLAIN_LENGTH in init_buf right off the bat. Instead it will grow as-needed to accomodate the handshake. SSL3_RT_MAX_PLAIN_LENGTH is rather larger than we probably need to receive, particularly as a server, so this seems a good plan. BUG=83 Change-Id: Id7f4024afc4c8a713b46b0d1625432315594350e Reviewed-on: https://boringssl-review.googlesource.com/8985 Reviewed-by: Adam Langley <agl@google.com> Commit-Queue: Adam Langley <agl@google.com> CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
diff --git a/ssl/dtls_method.c b/ssl/dtls_method.c index cf26092..15d90f6 100644 --- a/ssl/dtls_method.c +++ b/ssl/dtls_method.c
@@ -92,10 +92,6 @@ return ~(version - 0x0201); } -static int dtls1_begin_handshake(SSL *ssl) { - return 1; -} - static void dtls1_finish_handshake(SSL *ssl) { ssl->d1->handshake_read_seq = 0; ssl->d1->handshake_write_seq = 0; @@ -141,7 +137,6 @@ dtls1_version_to_wire, dtls1_new, dtls1_free, - dtls1_begin_handshake, dtls1_finish_handshake, dtls1_get_message, dtls1_hash_current_message,
diff --git a/ssl/handshake_client.c b/ssl/handshake_client.c index 6f9b2fc..fc4318e 100644 --- a/ssl/handshake_client.c +++ b/ssl/handshake_client.c
@@ -201,8 +201,7 @@ ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_START, 1); ssl->s3->hs = ssl_handshake_new(tls13_client_handshake); - if (ssl->s3->hs == NULL || - !ssl->method->begin_handshake(ssl)) { + if (ssl->s3->hs == NULL) { ret = -1; goto end; }
diff --git a/ssl/handshake_server.c b/ssl/handshake_server.c index 31a5030..4708dd0 100644 --- a/ssl/handshake_server.c +++ b/ssl/handshake_server.c
@@ -202,8 +202,7 @@ ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_START, 1); ssl->s3->hs = ssl_handshake_new(tls13_server_handshake); - if (ssl->s3->hs == NULL || - !ssl->method->begin_handshake(ssl)) { + if (ssl->s3->hs == NULL) { ret = -1; goto end; }
diff --git a/ssl/internal.h b/ssl/internal.h index f5180a7..2fb1492 100644 --- a/ssl/internal.h +++ b/ssl/internal.h
@@ -1039,9 +1039,6 @@ uint16_t (*version_to_wire)(uint16_t version); int (*ssl_new)(SSL *ssl); void (*ssl_free)(SSL *ssl); - /* begin_handshake is called to start a new handshake. It returns one on - * success and zero on error. */ - int (*begin_handshake)(SSL *ssl); /* finish_handshake is called when a handshake completes. */ void (*finish_handshake)(SSL *ssl); /* ssl_get_message reads the next handshake message. If |msg_type| is not -1,
diff --git a/ssl/s3_both.c b/ssl/s3_both.c index 8092eb9..cb4356b 100644 --- a/ssl/s3_both.c +++ b/ssl/s3_both.c
@@ -456,8 +456,15 @@ rand_len); /* Write out an equivalent SSLv3 ClientHello. */ + size_t max_v3_client_hello = SSL3_HM_HEADER_LENGTH + 2 /* version */ + + SSL3_RANDOM_SIZE + 1 /* session ID length */ + + 2 /* cipher list length */ + + CBS_len(&cipher_specs) / 3 * 2 + + 1 /* compression length */ + 1 /* compression */; CBB client_hello, hello_body, cipher_suites; - if (!CBB_init_fixed(&client_hello, (uint8_t *)ssl->init_buf->data, + CBB_zero(&client_hello); + if (!BUF_MEM_reserve(ssl->init_buf, max_v3_client_hello) || + !CBB_init_fixed(&client_hello, (uint8_t *)ssl->init_buf->data, ssl->init_buf->max) || !CBB_add_u8(&client_hello, SSL3_MT_CLIENT_HELLO) || !CBB_add_u24_length_prefixed(&client_hello, &hello_body) || @@ -512,6 +519,14 @@ int ssl3_get_message(SSL *ssl, int msg_type, enum ssl_hash_message_t hash_message) { again: + /* Re-create the handshake buffer if needed. */ + if (ssl->init_buf == NULL) { + ssl->init_buf = BUF_MEM_new(); + if (ssl->init_buf == NULL) { + return -1; + } + } + if (ssl->server && !ssl->s3->v2_hello_done) { /* Bypass the record layer for the first message to handle V2ClientHello. */ assert(hash_message == ssl_hash_message);
diff --git a/ssl/tls_method.c b/ssl/tls_method.c index 70b6bd1..cd6b453 100644 --- a/ssl/tls_method.c +++ b/ssl/tls_method.c
@@ -69,21 +69,6 @@ static uint16_t ssl3_version_to_wire(uint16_t version) { return version; } -static int ssl3_begin_handshake(SSL *ssl) { - if (ssl->init_buf != NULL) { - return 1; - } - - BUF_MEM *buf = BUF_MEM_new(); - if (buf == NULL || !BUF_MEM_reserve(buf, SSL3_RT_MAX_PLAIN_LENGTH)) { - BUF_MEM_free(buf); - return 0; - } - - ssl->init_buf = buf; - return 1; -} - static void ssl3_finish_handshake(SSL *ssl) { BUF_MEM_free(ssl->init_buf); ssl->init_buf = NULL; @@ -125,7 +110,6 @@ ssl3_version_to_wire, ssl3_new, ssl3_free, - ssl3_begin_handshake, ssl3_finish_handshake, ssl3_get_message, ssl3_hash_current_message,