Only handle RI extension for SSLv3
authorDr. Stephen Henson <steve@openssl.org>
Mon, 3 Nov 2014 17:47:11 +0000 (17:47 +0000)
committerDr. Stephen Henson <steve@openssl.org>
Wed, 19 Nov 2014 15:12:08 +0000 (15:12 +0000)
Don't send or parse any extensions other than RI (which is needed
to handle secure renegotation) for SSLv3.
Reviewed-by: Matt Caswell <matt@openssl.org>
ssl/t1_lib.c

index db45c60..149e7d6 100644 (file)
@@ -1147,15 +1147,38 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned c
                }
 #endif
 
-       /* don't add extensions for SSLv3 unless doing secure renegotiation */
-       if (s->client_version == SSL3_VERSION
-                                       && !s->s3->send_connection_binding)
-               return orig;
-
        ret+=2;
 
        if (ret>=limit) return NULL; /* this really never occurs, but ... */
 
+        /* Add RI if renegotiating */
+        if (s->renegotiate)
+          {
+          int el;
+
+          if(!ssl_add_clienthello_renegotiate_ext(s, 0, &el, 0))
+              {
+              SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
+              return NULL;
+              }
+
+          if((limit - ret - 4 - el) < 0) return NULL;
+
+          s2n(TLSEXT_TYPE_renegotiate,ret);
+          s2n(el,ret);
+
+          if(!ssl_add_clienthello_renegotiate_ext(s, ret, &el, el))
+              {
+              SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
+              return NULL;
+              }
+
+          ret += el;
+        }
+       /* Only add RI for SSLv3 */
+       if (s->client_version == SSL3_VERSION)
+               goto done;
+
        if (s->tlsext_hostname != NULL)
                { 
                /* Add TLS extension servername to the Client Hello message */
@@ -1188,31 +1211,6 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned c
                ret+=size_str;
                }
 
-        /* Add RI if renegotiating */
-        if (s->renegotiate)
-          {
-          int el;
-          
-          if(!ssl_add_clienthello_renegotiate_ext(s, 0, &el, 0))
-              {
-              SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
-              return NULL;
-              }
-
-          if((limit - ret - 4 - el) < 0) return NULL;
-          
-          s2n(TLSEXT_TYPE_renegotiate,ret);
-          s2n(el,ret);
-
-          if(!ssl_add_clienthello_renegotiate_ext(s, ret, &el, el))
-              {
-              SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
-              return NULL;
-              }
-
-          ret += el;
-        }
-
 #ifndef OPENSSL_NO_SRP
        /* Add SRP username if there is one */
        if (s->srp_ctx.login != NULL)
@@ -1484,11 +1482,8 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned c
        if (!custom_ext_add(s, 0, &ret, limit, al))
                return NULL;
 #ifdef TLSEXT_TYPE_encrypt_then_mac
-       if (s->version != SSL3_VERSION)
-               {
-               s2n(TLSEXT_TYPE_encrypt_then_mac,ret);
-               s2n(0,ret);
-               }
+       s2n(TLSEXT_TYPE_encrypt_then_mac,ret);
+       s2n(0,ret);
 #endif
 
        /* Add padding to workaround bugs in F5 terminators.
@@ -1521,6 +1516,8 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned c
                        }
                }
 
+       done:
+
        if ((extdatalen = ret-orig-2)== 0) 
                return orig;
 
@@ -1542,21 +1539,10 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned c
        int using_ecc = (alg_k & (SSL_kECDHE|SSL_kECDHr|SSL_kECDHe)) || (alg_a & SSL_aECDSA);
        using_ecc = using_ecc && (s->session->tlsext_ecpointformatlist != NULL);
 #endif
-       /* don't add extensions for SSLv3, unless doing secure renegotiation */
-       if (s->version == SSL3_VERSION && !s->s3->send_connection_binding)
-               return orig;
        
        ret+=2;
        if (ret>=limit) return NULL; /* this really never occurs, but ... */
 
-       if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
-               { 
-               if ((long)(limit - ret - 4) < 0) return NULL; 
-
-               s2n(TLSEXT_TYPE_server_name,ret);
-               s2n(0,ret);
-               }
-
        if(s->s3->send_connection_binding)
         {
           int el;
@@ -1581,6 +1567,18 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned c
           ret += el;
         }
 
+       /* Only add RI for SSLv3 */
+       if (s->version == SSL3_VERSION)
+               goto done;
+
+       if (!s->hit && s->servername_done == 1 && s->session->tlsext_hostname != NULL)
+               {
+               if ((long)(limit - ret - 4) < 0) return NULL;
+
+               s2n(TLSEXT_TYPE_server_name,ret);
+               s2n(0,ret);
+               }
+
 #ifndef OPENSSL_NO_EC
        if (using_ecc)
                {
@@ -1721,12 +1719,11 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned c
 #ifdef TLSEXT_TYPE_encrypt_then_mac
        if (s->s3->flags & TLS1_FLAGS_ENCRYPT_THEN_MAC)
                {
-               /* Don't use encrypt_then_mac if AEAD, RC4 or SSL 3.0:
+               /* Don't use encrypt_then_mac if AEAD or RC4
                 * might want to disable for other cases too.
                 */
                if (s->s3->tmp.new_cipher->algorithm_mac == SSL_AEAD
-                   || s->s3->tmp.new_cipher->algorithm_enc == SSL_RC4
-                   || s->version == SSL3_VERSION)
+                   || s->s3->tmp.new_cipher->algorithm_enc == SSL_RC4)
                        s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC;
                else
                        {
@@ -1751,6 +1748,8 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned c
                ret += len;
                }
 
+       done:
+
        if ((extdatalen = ret-orig-2)== 0) 
                return orig;
 
@@ -1973,6 +1972,14 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                if (s->tlsext_debug_cb)
                        s->tlsext_debug_cb(s, 0, type, data, size,
                                                s->tlsext_debug_arg);
+               if (type == TLSEXT_TYPE_renegotiate)
+                       {
+                       if(!ssl_parse_clienthello_renegotiate_ext(s, data, size, al))
+                               return 0;
+                       renegotiate_seen = 1;
+                       }
+               else if (s->version == SSL3_VERSION)
+                       {}
 /* The servername extension is treated as follows:
 
    - Only the hostname type is supported with a maximum length of 255.
@@ -1996,7 +2003,7 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
 
 */      
 
-               if (type == TLSEXT_TYPE_server_name)
+               else if (type == TLSEXT_TYPE_server_name)
                        {
                        unsigned char *sdata;
                        int servname_type;
@@ -2217,12 +2224,6 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                                return 0;
                                }
                        }
-               else if (type == TLSEXT_TYPE_renegotiate)
-                       {
-                       if(!ssl_parse_clienthello_renegotiate_ext(s, data, size, al))
-                               return 0;
-                       renegotiate_seen = 1;
-                       }
                else if (type == TLSEXT_TYPE_signature_algorithms)
                        {
                        int dsize;
@@ -2418,10 +2419,7 @@ static int ssl_scan_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char
                         }
 #ifdef TLSEXT_TYPE_encrypt_then_mac
                else if (type == TLSEXT_TYPE_encrypt_then_mac)
-                       {
-                       if (s->version != SSL3_VERSION)
-                               s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC;
-                       }
+                       s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC;
 #endif
                /* If this ClientHello extension was unhandled and this is 
                 * a nonresumed connection, check whether the extension is a 
@@ -2544,7 +2542,16 @@ static int ssl_scan_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char
                        s->tlsext_debug_cb(s, 1, type, data, size,
                                                s->tlsext_debug_arg);
 
-               if (type == TLSEXT_TYPE_server_name)
+
+               if (type == TLSEXT_TYPE_renegotiate)
+                       {
+                       if(!ssl_parse_serverhello_renegotiate_ext(s, data, size, al))
+                               return 0;
+                       renegotiate_seen = 1;
+                       }
+               else if (s->version == SSL3_VERSION)
+                       {}
+               else if (type == TLSEXT_TYPE_server_name)
                        {
                        if (s->tlsext_hostname == NULL || size > 0)
                                {
@@ -2726,13 +2733,6 @@ static int ssl_scan_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char
                        memcpy(s->s3->alpn_selected, data + 3, len);
                        s->s3->alpn_selected_len = len;
                        }
-
-               else if (type == TLSEXT_TYPE_renegotiate)
-                       {
-                       if(!ssl_parse_serverhello_renegotiate_ext(s, data, size, al))
-                               return 0;
-                       renegotiate_seen = 1;
-                       }
 #ifndef OPENSSL_NO_HEARTBEATS
                else if (type == TLSEXT_TYPE_heartbeat)
                        {
@@ -2759,10 +2759,9 @@ static int ssl_scan_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char
 #ifdef TLSEXT_TYPE_encrypt_then_mac
                else if (type == TLSEXT_TYPE_encrypt_then_mac)
                        {
-                       /* Ignore if inappropriate ciphersuite or SSL 3.0 */
+                       /* Ignore if inappropriate ciphersuite */
                        if (s->s3->tmp.new_cipher->algorithm_mac != SSL_AEAD
-                           && s->s3->tmp.new_cipher->algorithm_enc != SSL_RC4
-                           && s->version != SSL3_VERSION)
+                           && s->s3->tmp.new_cipher->algorithm_enc != SSL_RC4)
                                s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC;
                        }
 #endif