Description: Check for null bytes in CN/subjAltName
Origin: http://www.openwall.com/lists/oss-security/2010/06/14/4
Author: Ludwig Nussel <ludwig.nussel@suse.de>
Bug-Debian: http://bugs.debian.org/587445
--- w3m-0.5.2.orig/istream.c
+++ w3m-0.5.2/istream.c
@@ -447,8 +447,17 @@ ssl_check_cert_ident(X509 * x, char *hos
if (!seen_dnsname)
seen_dnsname = Strnew();
+ /* replace \0 to make full string visible to user */
+ if (sl != strlen(sn)) {
+ int i;
+ for (i = 0; i < sl; ++i) {
+ if (!sn[i])
+ sn[i] = '!';
+ }
+ }
Strcat_m_charp(seen_dnsname, sn, " ", NULL);
- if (ssl_match_cert_ident(sn, sl, hostname))
+ if (sl == strlen(sn) /* catch \0 in SAN */
+ && ssl_match_cert_ident(sn, sl, hostname))
break;
}
}
@@ -466,16 +475,27 @@ ssl_check_cert_ident(X509 * x, char *hos
if (match_ident == FALSE && ret == NULL) {
X509_NAME *xn;
char buf[2048];
+ int slen;
xn = X509_get_subject_name(x);
- if (X509_NAME_get_text_by_NID(xn, NID_commonName,
- buf, sizeof(buf)) == -1)
+ slen = X509_NAME_get_text_by_NID(xn, NID_commonName, buf, sizeof(buf));
+ if ( slen == -1)
/* FIXME: gettextize? */
ret = Strnew_charp("Unable to get common name from peer cert");
- else if (!ssl_match_cert_ident(buf, strlen(buf), hostname))
+ else if (slen != strlen(buf)
+ || !ssl_match_cert_ident(buf, strlen(buf), hostname)) {
+ /* replace \0 to make full string visible to user */
+ if (slen != strlen(buf)) {
+ int i;
+ for (i = 0; i < slen; ++i) {
+ if (!buf[i])
+ buf[i] = '!';
+ }
+ }
/* FIXME: gettextize? */
ret = Sprintf("Bad cert ident %s from %s", buf, hostname);
+ }
else
match_ident = TRUE;
}
