wbrawner/openssl
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Better SSLv2 cipher-suite enforcement

Browse source 
Based on patch by: Nimrod Aviram <nimrod.aviram@gmail.com>

CVE-2015-3197

Reviewed-by: Tim Hudson <tjh@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
This commit is contained in:
Viktor Dukhovni 2015-12-30 22:44:51 -05:00 committed by Matt Caswell
parent 3665fa2543
commit d81a160058
1 changed files with 13 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

15
ssl/s2_srvr.c
View file

@ -402,7 +402,7 @@ static int get_client_master_key(SSL *s)
}
cp = ssl2_get_cipher_by_char(p);
if (cp == NULL) {
if (cp == NULL || sk_SSL_CIPHER_find(s->session->ciphers, cp) < 0) {
ssl2_return_error(s, SSL2_PE_NO_CIPHER);
SSLerr(SSL_F_GET_CLIENT_MASTER_KEY, SSL_R_NO_CIPHER_MATCH);
return (-1);
@ -692,8 +692,12 @@ static int get_client_hello(SSL *s)
prio = cs;
allow = cl;
}
/* Generate list of SSLv2 ciphers shared between client and server */
for (z = 0; z < sk_SSL_CIPHER_num(prio); z++) {
if (sk_SSL_CIPHER_find(allow, sk_SSL_CIPHER_value(prio, z)) < 0) {
const SSL_CIPHER *cp = sk_SSL_CIPHER_value(prio, z);
if ((cp->algorithm_ssl & SSL_SSLV2) == 0 ||
sk_SSL_CIPHER_find(allow, cp) < 0) {
(void)sk_SSL_CIPHER_delete(prio, z);
z--;
}
@ -702,6 +706,13 @@ static int get_client_hello(SSL *s)
sk_SSL_CIPHER_free(s->session->ciphers);
s->session->ciphers = prio;
}
/* Make sure we have at least one cipher in common */
if (sk_SSL_CIPHER_num(s->session->ciphers) == 0) {
ssl2_return_error(s, SSL2_PE_NO_CIPHER);
SSLerr(SSL_F_GET_CLIENT_HELLO, SSL_R_NO_CIPHER_MATCH);
return -1;
}
/*
* s->session->ciphers should now have a list of ciphers that are on
* both the client and server. This list is ordered by the order the