Remove remnants of the HRR message.
It has now been folded into ServerHello. Additionally, TLS 1.2 and TLS
1.3 ServerHellos are now more uniform, so we can avoid the extra
ServerHello parser.
Change-Id: I46641128c3f65fe37e7effca5bef4a76bf3ba84c
Reviewed-on: https://boringssl-review.googlesource.com/26524
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Steven Valdez <svaldez@google.com>
diff --git a/include/openssl/ssl3.h b/include/openssl/ssl3.h
index ae0be88..e32a6d7 100644
--- a/include/openssl/ssl3.h
+++ b/include/openssl/ssl3.h
@@ -300,7 +300,6 @@
#define SSL3_MT_SERVER_HELLO 2
#define SSL3_MT_NEW_SESSION_TICKET 4
#define SSL3_MT_END_OF_EARLY_DATA 5
-#define SSL3_MT_HELLO_RETRY_REQUEST 6
#define SSL3_MT_ENCRYPTED_EXTENSIONS 8
#define SSL3_MT_CERTIFICATE 11
#define SSL3_MT_SERVER_KEY_EXCHANGE 12
diff --git a/ssl/handshake_client.cc b/ssl/handshake_client.cc
index e8dd0d3..0b352c2 100644
--- a/ssl/handshake_client.cc
+++ b/ssl/handshake_client.cc
@@ -339,50 +339,21 @@
return ssl->method->add_message(ssl, std::move(msg));
}
-static int parse_server_version(SSL_HANDSHAKE *hs, uint16_t *out,
- const SSLMessage &msg) {
+static bool parse_supported_versions(SSL_HANDSHAKE *hs, uint16_t *version,
+ const CBS *in) {
+ // If the outer version is not TLS 1.2, or there is no extensions block, use
+ // the outer version.
+ if (*version != TLS1_2_VERSION || CBS_len(in) == 0) {
+ return true;
+ }
+
SSL *const ssl = hs->ssl;
- if (msg.type != SSL3_MT_SERVER_HELLO &&
- msg.type != SSL3_MT_HELLO_RETRY_REQUEST) {
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
- return 0;
- }
-
- CBS server_hello = msg.body;
- if (!CBS_get_u16(&server_hello, out)) {
+ CBS copy = *in, extensions;
+ if (!CBS_get_u16_length_prefixed(©, &extensions) ||
+ CBS_len(©) != 0) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return 0;
- }
-
- // The server version may also be in the supported_versions extension if
- // applicable.
- if (msg.type != SSL3_MT_SERVER_HELLO || *out != TLS1_2_VERSION) {
- return 1;
- }
-
- uint8_t sid_length;
- if (!CBS_skip(&server_hello, SSL3_RANDOM_SIZE) ||
- !CBS_get_u8(&server_hello, &sid_length) ||
- !CBS_skip(&server_hello, sid_length + 2 /* cipher_suite */ +
- 1 /* compression_method */)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return 0;
- }
-
- // The extensions block may not be present.
- if (CBS_len(&server_hello) == 0) {
- return 1;
- }
-
- CBS extensions;
- if (!CBS_get_u16_length_prefixed(&server_hello, &extensions) ||
- CBS_len(&server_hello) != 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return 0;
+ return false;
}
bool have_supported_versions;
@@ -397,17 +368,18 @@
OPENSSL_ARRAY_SIZE(ext_types),
1 /* ignore unknown */)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
- return 0;
+ return false;
}
+ // Override the outer version with the extension, if present.
if (have_supported_versions &&
- (!CBS_get_u16(&supported_versions, out) ||
+ (!CBS_get_u16(&supported_versions, version) ||
CBS_len(&supported_versions) != 0)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return 0;
+ return false;
}
- return 1;
+ return true;
}
static enum ssl_hs_wait_t do_start_connect(SSL_HANDSHAKE *hs) {
@@ -567,8 +539,26 @@
return ssl_hs_read_server_hello;
}
- uint16_t server_version;
- if (!parse_server_version(hs, &server_version, msg)) {
+ if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) {
+ return ssl_hs_error;
+ }
+
+ CBS server_hello = msg.body, server_random, session_id;
+ uint16_t server_version, cipher_suite;
+ uint8_t compression_method;
+ if (!CBS_get_u16(&server_hello, &server_version) ||
+ !CBS_get_bytes(&server_hello, &server_random, SSL3_RANDOM_SIZE) ||
+ !CBS_get_u8_length_prefixed(&server_hello, &session_id) ||
+ CBS_len(&session_id) > SSL3_SESSION_ID_SIZE ||
+ !CBS_get_u16(&server_hello, &cipher_suite) ||
+ !CBS_get_u8(&server_hello, &compression_method)) {
+ OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
+ ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
+ return ssl_hs_error;
+ }
+
+ // Use the supported_versions extension if applicable.
+ if (!parse_supported_versions(hs, &server_version, &server_hello)) {
return ssl_hs_error;
}
@@ -609,24 +599,6 @@
return ssl_hs_error;
}
- if (!ssl_check_message_type(ssl, msg, SSL3_MT_SERVER_HELLO)) {
- return ssl_hs_error;
- }
-
- CBS server_hello = msg.body, server_random, session_id;
- uint16_t cipher_suite;
- uint8_t compression_method;
- if (!CBS_skip(&server_hello, 2 /* version */) ||
- !CBS_get_bytes(&server_hello, &server_random, SSL3_RANDOM_SIZE) ||
- !CBS_get_u8_length_prefixed(&server_hello, &session_id) ||
- CBS_len(&session_id) > SSL3_SESSION_ID_SIZE ||
- !CBS_get_u16(&server_hello, &cipher_suite) ||
- !CBS_get_u8(&server_hello, &compression_method)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
- return ssl_hs_error;
- }
-
// Copy over the server random.
OPENSSL_memcpy(ssl->s3->server_random, CBS_data(&server_random),
SSL3_RANDOM_SIZE);
