Fix possible buffer overrun.
authorBen Laurie <ben@links.org>
Wed, 23 Apr 2014 17:13:20 +0000 (18:13 +0100)
committerBen Laurie <ben@links.org>
Tue, 1 Jul 2014 23:11:10 +0000 (00:11 +0100)
(cherry picked from commit 2db3ea29298bdc347f15fbfab6d5746022f05101)

Conflicts:
ssl/t1_lib.c

ssl/ssl_locl.h
ssl/t1_lib.c

index 261ba0d..0b48c73 100644 (file)
@@ -1284,8 +1284,8 @@ int tls1_shared_list(SSL *s,
                        const unsigned char *l1, size_t l1len,
                        const unsigned char *l2, size_t l2len,
                        int nmatch);
-unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit, int *al);
-unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit, int *al);
+unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit, int *al);
+unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit, int *al);
 int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **data, unsigned char *d, int n);
 int ssl_check_clienthello_tlsext_late(SSL *s);
 int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **data, unsigned char *d, int n);
index d784639..4374d6a 100644 (file)
@@ -1106,10 +1106,11 @@ static int tls_use_ticket(SSL *s)
        return ssl_security(s, SSL_SECOP_TICKET, 0, 0, NULL);
        }
 
-unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit, int *al)
+unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit, int *al)
        {
        int extdatalen=0;
-       unsigned char *ret = p;
+       unsigned char *orig = buf;
+       unsigned char *ret = buf;
 #ifndef OPENSSL_NO_EC
        /* See if we support any ECC ciphersuites */
        int using_ecc = 0;
@@ -1138,7 +1139,7 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned cha
        /* don't add extensions for SSLv3 unless doing secure renegotiation */
        if (s->client_version == SSL3_VERSION
                                        && !s->s3->send_connection_binding)
-               return p;
+               return orig;
 
        ret+=2;
 
@@ -1187,7 +1188,7 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned cha
               return NULL;
               }
 
-          if((limit - p - 4 - el) < 0) return NULL;
+          if((limit - ret - 4 - el) < 0) return NULL;
           
           s2n(TLSEXT_TYPE_renegotiate,ret);
           s2n(el,ret);
@@ -1460,7 +1461,7 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned cha
 
                 ssl_add_clienthello_use_srtp_ext(s, 0, &el, 0);
                 
-                if((limit - p - 4 - el) < 0) return NULL;
+                if((limit - ret - 4 - el) < 0) return NULL;
 
                 s2n(TLSEXT_TYPE_use_srtp,ret);
                 s2n(el,ret);
@@ -1541,17 +1542,18 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned cha
                        }
                }
 
-       if ((extdatalen = ret-p-2) == 0)
-               return p;
+       if ((extdatalen = ret-orig-2)== 0) 
+               return orig;
 
-       s2n(extdatalen,p);
+       s2n(extdatalen, orig);
        return ret;
        }
 
-unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit, int *al)
+unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit, int *al)
        {
        int extdatalen=0;
-       unsigned char *ret = p;
+       unsigned char *orig = buf;
+       unsigned char *ret = buf;
        size_t i;
        custom_srv_ext_record *record;
 #ifndef OPENSSL_NO_NEXTPROTONEG
@@ -1565,7 +1567,7 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned cha
 #endif
        /* don't add extensions for SSLv3, unless doing secure renegotiation */
        if (s->version == SSL3_VERSION && !s->s3->send_connection_binding)
-               return p;
+               return orig;
        
        ret+=2;
        if (ret>=limit) return NULL; /* this really never occurs, but ... */
@@ -1588,7 +1590,7 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned cha
               return NULL;
               }
 
-          if((limit - p - 4 - el) < 0) return NULL;
+          if((limit - ret - 4 - el) < 0) return NULL;
           
           s2n(TLSEXT_TYPE_renegotiate,ret);
           s2n(el,ret);
@@ -1668,7 +1670,7 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned cha
 
                 ssl_add_serverhello_use_srtp_ext(s, 0, &el, 0);
                 
-                if((limit - p - 4 - el) < 0) return NULL;
+                if((limit - ret - 4 - el) < 0) return NULL;
 
                 s2n(TLSEXT_TYPE_use_srtp,ret);
                 s2n(el,ret);
@@ -1794,10 +1796,10 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned cha
                ret += len;
                }
 
-       if ((extdatalen = ret-p-2)== 0) 
-               return p;
+       if ((extdatalen = ret-orig-2)== 0) 
+               return orig;
 
-       s2n(extdatalen,p);
+       s2n(extdatalen, orig);
        return ret;
        }