Convert ssl_parse_serverhello_renegotiate_ext to CBS.

ok miod@ jsing@

4 files changed, 42 insertions, 38 deletions

diff --git a/src/lib/libssl/src/ssl/ssl_locl.h b/src/lib/libssl/src/ssl/ssl_locl.h
index b55e8265af..43c6974268 100644
--- a/src/lib/libssl/src/ssl/ssl_locl.h
+++ b/src/lib/libssl/src/ssl/ssl_locl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_locl.h,v 1.92 2015/06/20 04:04:35 doug Exp $ */
+/* $OpenBSD: ssl_locl.h,v 1.93 2015/06/20 16:42:48 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -835,7 +835,7 @@ EVP_MD_CTX* ssl_replace_hash(EVP_MD_CTX **hash, const EVP_MD *md);
 void ssl_clear_hash_ctx(EVP_MD_CTX **hash);
 int ssl_add_serverhello_renegotiate_ext(SSL *s, unsigned char *p,
     int *len, int maxlen);
-int ssl_parse_serverhello_renegotiate_ext(SSL *s, unsigned char *d,
+int ssl_parse_serverhello_renegotiate_ext(SSL *s, const unsigned char *d,
     int len, int *al);
 int ssl_add_clienthello_renegotiate_ext(SSL *s, unsigned char *p,
     int *len, int maxlen);
diff --git a/src/lib/libssl/src/ssl/t1_reneg.c b/src/lib/libssl/src/ssl/t1_reneg.c
index 52d1754d94..294a632b8f 100644
--- a/src/lib/libssl/src/ssl/t1_reneg.c
+++ b/src/lib/libssl/src/ssl/t1_reneg.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: t1_reneg.c,v 1.10 2015/06/20 04:04:36 doug Exp $ */
+/* $OpenBSD: t1_reneg.c,v 1.11 2015/06/20 16:42:48 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -224,29 +224,28 @@ ssl_add_serverhello_renegotiate_ext(SSL *s, unsigned char *p, int *len,
 /* Parse the server's renegotiation binding and abort if it's not
    right */
 int
-ssl_parse_serverhello_renegotiate_ext(SSL *s, unsigned char *d, int len,
-    int *al)
+ssl_parse_serverhello_renegotiate_ext(SSL *s, const unsigned char *d, int len, int *al)
 {
+        CBS cbs, reneg, previous_client, previous_server;
         int expected_len = s->s3->previous_client_finished_len +
             s->s3->previous_server_finished_len;
-        int ilen;
 
         /* Check for logic errors */
         OPENSSL_assert(!expected_len || s->s3->previous_client_finished_len);
         OPENSSL_assert(!expected_len || s->s3->previous_server_finished_len);
 
-        /* Parse the length byte */
-        if (len < 1) {
+        if (len < 0) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_ENCODING_ERR);
                 *al = SSL_AD_ILLEGAL_PARAMETER;
                 return 0;
         }
-        ilen = *d;
-        d++;
 
-        /* Consistency check */
-        if (ilen + 1 != len) {
+        CBS_init(&cbs, d, len);
+
+        if (!CBS_get_u8_length_prefixed(&cbs, &reneg) ||
+            /* Consistency check */
+            CBS_len(&cbs) != 0) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_ENCODING_ERR);
                 *al = SSL_AD_ILLEGAL_PARAMETER;
@@ -254,24 +253,27 @@ ssl_parse_serverhello_renegotiate_ext(SSL *s, unsigned char *d, int len,
         }
 
         /* Check that the extension matches */
-        if (ilen != expected_len) {
+        if (CBS_len(&reneg) != expected_len ||
+            !CBS_get_bytes(&reneg, &previous_client,
+            s->s3->previous_client_finished_len) ||
+            !CBS_get_bytes(&reneg, &previous_server,
+            s->s3->previous_server_finished_len) ||
+            CBS_len(&reneg) != 0) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_MISMATCH);
                 *al = SSL_AD_HANDSHAKE_FAILURE;
                 return 0;
         }
 
-        if (timingsafe_memcmp(d, s->s3->previous_client_finished,
-            s->s3->previous_client_finished_len) != 0) {
+        if (!CBS_mem_equal(&previous_client, s->s3->previous_client_finished,
+            CBS_len(&previous_client))) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_MISMATCH);
                 *al = SSL_AD_HANDSHAKE_FAILURE;
                 return 0;
         }
-        d += s->s3->previous_client_finished_len;
-
-        if (timingsafe_memcmp(d, s->s3->previous_server_finished,
-            s->s3->previous_server_finished_len)) {
+        if (!CBS_mem_equal(&previous_server, s->s3->previous_server_finished,
+            CBS_len(&previous_server))) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_MISMATCH);
                 *al = SSL_AD_ILLEGAL_PARAMETER;
diff --git a/src/lib/libssl/ssl_locl.h b/src/lib/libssl/ssl_locl.h
index b55e8265af..43c6974268 100644
--- a/src/lib/libssl/ssl_locl.h
+++ b/src/lib/libssl/ssl_locl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_locl.h,v 1.92 2015/06/20 04:04:35 doug Exp $ */
+/* $OpenBSD: ssl_locl.h,v 1.93 2015/06/20 16:42:48 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -835,7 +835,7 @@ EVP_MD_CTX* ssl_replace_hash(EVP_MD_CTX **hash, const EVP_MD *md);
 void ssl_clear_hash_ctx(EVP_MD_CTX **hash);
 int ssl_add_serverhello_renegotiate_ext(SSL *s, unsigned char *p,
     int *len, int maxlen);
-int ssl_parse_serverhello_renegotiate_ext(SSL *s, unsigned char *d,
+int ssl_parse_serverhello_renegotiate_ext(SSL *s, const unsigned char *d,
     int len, int *al);
 int ssl_add_clienthello_renegotiate_ext(SSL *s, unsigned char *p,
     int *len, int maxlen);
diff --git a/src/lib/libssl/t1_reneg.c b/src/lib/libssl/t1_reneg.c
index 52d1754d94..294a632b8f 100644
--- a/src/lib/libssl/t1_reneg.c
+++ b/src/lib/libssl/t1_reneg.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: t1_reneg.c,v 1.10 2015/06/20 04:04:36 doug Exp $ */
+/* $OpenBSD: t1_reneg.c,v 1.11 2015/06/20 16:42:48 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -224,29 +224,28 @@ ssl_add_serverhello_renegotiate_ext(SSL *s, unsigned char *p, int *len,
 /* Parse the server's renegotiation binding and abort if it's not
    right */
 int
-ssl_parse_serverhello_renegotiate_ext(SSL *s, unsigned char *d, int len,
-    int *al)
+ssl_parse_serverhello_renegotiate_ext(SSL *s, const unsigned char *d, int len, int *al)
 {
+        CBS cbs, reneg, previous_client, previous_server;
         int expected_len = s->s3->previous_client_finished_len +
             s->s3->previous_server_finished_len;
-        int ilen;
 
         /* Check for logic errors */
         OPENSSL_assert(!expected_len || s->s3->previous_client_finished_len);
         OPENSSL_assert(!expected_len || s->s3->previous_server_finished_len);
 
-        /* Parse the length byte */
-        if (len < 1) {
+        if (len < 0) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_ENCODING_ERR);
                 *al = SSL_AD_ILLEGAL_PARAMETER;
                 return 0;
         }
-        ilen = *d;
-        d++;
 
-        /* Consistency check */
-        if (ilen + 1 != len) {
+        CBS_init(&cbs, d, len);
+
+        if (!CBS_get_u8_length_prefixed(&cbs, &reneg) ||
+            /* Consistency check */
+            CBS_len(&cbs) != 0) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_ENCODING_ERR);
                 *al = SSL_AD_ILLEGAL_PARAMETER;
@@ -254,24 +253,27 @@ ssl_parse_serverhello_renegotiate_ext(SSL *s, unsigned char *d, int len,
         }
 
         /* Check that the extension matches */
-        if (ilen != expected_len) {
+        if (CBS_len(&reneg) != expected_len ||
+            !CBS_get_bytes(&reneg, &previous_client,
+            s->s3->previous_client_finished_len) ||
+            !CBS_get_bytes(&reneg, &previous_server,
+            s->s3->previous_server_finished_len) ||
+            CBS_len(&reneg) != 0) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_MISMATCH);
                 *al = SSL_AD_HANDSHAKE_FAILURE;
                 return 0;
         }
 
-        if (timingsafe_memcmp(d, s->s3->previous_client_finished,
-            s->s3->previous_client_finished_len) != 0) {
+        if (!CBS_mem_equal(&previous_client, s->s3->previous_client_finished,
+            CBS_len(&previous_client))) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_MISMATCH);
                 *al = SSL_AD_HANDSHAKE_FAILURE;
                 return 0;
         }
-        d += s->s3->previous_client_finished_len;
-
-        if (timingsafe_memcmp(d, s->s3->previous_server_finished,
-            s->s3->previous_server_finished_len)) {
+        if (!CBS_mem_equal(&previous_server, s->s3->previous_server_finished,
+            CBS_len(&previous_server))) {
                 SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_RENEGOTIATE_EXT,
                     SSL_R_RENEGOTIATION_MISMATCH);
                 *al = SSL_AD_ILLEGAL_PARAMETER;