kris/boringssl
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Turn off Finished-based APIs at TLS 1.3 and SSL 3.0.

Browse Source 
tls-unique isn't defined at TLS 1.3 yet. (Given that it was too small in
1.2, they may just define a new one entirely?) SSL_get_(peer_)finished
doesn't work at 1.3 and is only used in lieu of computing tls-unique,
also undefined at SSL 3.0.

This is in preparation for trimming the copies of the Finished messages
we retain.

Change-Id: Iace99f2baea92c511c4041c592300dfbbe7226e2
Reviewed-on: https://boringssl-review.googlesource.com/11568
Reviewed-by: Adam Langley <agl@google.com>
This commit is contained in:
David Benjamin 2016-10-08 11:24:09 -04:00 committed by Adam Langley
parent a4c8ff0190
commit ced00b4258
2 changed files with 28 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
include/openssl/ssl.h
View File

@ -3471,14 +3471,15 @@ OPENSSL_EXPORT int SSL_want(const SSL *ssl);
/* SSL_get_finished writes up to |count| bytes of the Finished message sent by
* |ssl| to |buf|. It returns the total untruncated length or zero if none has
* been sent yet.
* been sent yet. At SSL 3.0 or TLS 1.3 and later, it returns zero.
*
* Use |SSL_get_tls_unique| instead. */
OPENSSL_EXPORT size_t SSL_get_finished(const SSL *ssl, void *buf, size_t count);
/* SSL_get_peer_finished writes up to |count| bytes of the Finished message
* received from |ssl|'s peer to |buf|. It returns the total untruncated length
* or zero if none has been received yet.
* or zero if none has been received yet. At SSL 3.0 or TLS 1.3 and later, it
* returns zero.
*
* Use |SSL_get_tls_unique| instead. */
OPENSSL_EXPORT size_t SSL_get_peer_finished(const SSL *ssl, void *buf,

46
ssl/ssl_lib.c
View File

@ -1064,6 +1064,13 @@ STACK_OF(X509) *SSL_get_peer_cert_chain(const SSL *ssl) {
int SSL_get_tls_unique(const SSL *ssl, uint8_t *out, size_t *out_len,
size_t max_out) {
/* tls-unique is not defined for SSL 3.0 or TLS 1.3. */
if (!ssl->s3->initial_handshake_complete ||
ssl3_protocol_version(ssl) < TLS1_VERSION ||
ssl3_protocol_version(ssl) >= TLS1_3_VERSION) {
goto err;
}
/* The tls-unique value is the first Finished message in the handshake, which
* is the client's in a full handshake and the server's for a resumption. See
* https://tools.ietf.org/html/rfc5929#section-3.1. */
@ -1078,11 +1085,6 @@ int SSL_get_tls_unique(const SSL *ssl, uint8_t *out, size_t *out_len,
finished_len = ssl->s3->previous_server_finished_len;
}
if (!ssl->s3->initial_handshake_complete ||
ssl->version < TLS1_VERSION) {
goto err;
}
*out_len = finished_len;
if (finished_len > max_out) {
*out_len = max_out;
@ -1232,30 +1234,32 @@ int SSL_set_rfd(SSL *ssl, int fd) {
}
size_t SSL_get_finished(const SSL *ssl, void *buf, size_t count) {
size_t ret = 0;
if (ssl->s3 != NULL) {
ret = ssl->s3->tmp.finish_md_len;
if (count > ret) {
count = ret;
}
memcpy(buf, ssl->s3->tmp.finish_md, count);
if (!ssl->s3->initial_handshake_complete ||
ssl3_protocol_version(ssl) < TLS1_VERSION ||
ssl3_protocol_version(ssl) >= TLS1_3_VERSION) {
return 0;
}
size_t ret = ssl->s3->tmp.finish_md_len;
if (count > ret) {
count = ret;
}
memcpy(buf, ssl->s3->tmp.finish_md, count);
return ret;
}
size_t SSL_get_peer_finished(const SSL *ssl, void *buf, size_t count) {
size_t ret = 0;
if (ssl->s3 != NULL) {
ret = ssl->s3->tmp.peer_finish_md_len;
if (count > ret) {
count = ret;
}
memcpy(buf, ssl->s3->tmp.peer_finish_md, count);
if (!ssl->s3->initial_handshake_complete ||
ssl3_protocol_version(ssl) < TLS1_VERSION ||
ssl3_protocol_version(ssl) >= TLS1_3_VERSION) {
return 0;
}
size_t ret = ssl->s3->tmp.peer_finish_md_len;
if (count > ret) {
count = ret;
}
memcpy(buf, ssl->s3->tmp.peer_finish_md, count);
return ret;
}