From 2db3ea29298bdc347f15fbfab6d5746022f05101 Mon Sep 17 00:00:00 2001 From: Ben Laurie Date: Wed, 23 Apr 2014 18:13:20 +0100 Subject: [PATCH] Fix possible buffer overrun. --- ssl/ssl_locl.h | 4 ++-- ssl/t1_lib.c | 34 ++++++++++++++++++---------------- 2 files changed, 20 insertions(+), 18 deletions(-) diff --git a/ssl/ssl_locl.h b/ssl/ssl_locl.h index eb4d8f2fa9..97cde4055d 100644 --- a/ssl/ssl_locl.h +++ b/ssl/ssl_locl.h @@ -1096,8 +1096,8 @@ int tls1_ec_nid2curve_id(int nid); #endif /* OPENSSL_NO_EC */ #ifndef OPENSSL_NO_TLSEXT -unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit); -unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned char *limit); +unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit); +unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit); int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **data, unsigned char *d, int n, int *al); int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **data, unsigned char *d, int n, int *al); int ssl_prepare_clienthello_tlsext(SSL *s); diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c index f7abce9258..f6a480d0e2 100644 --- a/ssl/t1_lib.c +++ b/ssl/t1_lib.c @@ -352,15 +352,16 @@ int tls12_get_req_sig_algs(SSL *s, unsigned char *p) return (int)slen; } -unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit) +unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit) { int extdatalen=0; - unsigned char *ret = p; + unsigned char *orig = buf; + unsigned char *ret = buf; /* 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; @@ -409,7 +410,7 @@ 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); @@ -650,7 +651,7 @@ 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); @@ -693,24 +694,25 @@ 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) +unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit) { int extdatalen=0; - unsigned char *ret = p; + unsigned char *orig = buf; + unsigned char *ret = buf; #ifndef OPENSSL_NO_NEXTPROTONEG int next_proto_neg_seen; #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 ... */ @@ -733,7 +735,7 @@ 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); @@ -813,7 +815,7 @@ 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); @@ -884,10 +886,10 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned cha } #endif - if ((extdatalen = ret-p-2)== 0) - return p; + if ((extdatalen = ret-orig-2)== 0) + return orig; - s2n(extdatalen,p); + s2n(extdatalen, orig); return ret; } -- 2.34.1