| From d81a1600588b726c2bdccda7efad3cc7a87d6245 Mon Sep 17 00:00:00 2001 |
| From: Viktor Dukhovni <openssl-users@dukhovni.org> |
| Date: Wed, 30 Dec 2015 22:44:51 -0500 |
| Subject: [PATCH] Better SSLv2 cipher-suite enforcement |
| |
| 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> |
| |
| Upstream-Status: Backport |
| https://github.com/openssl/openssl/commit/d81a1600588b726c2bdccda7efad3cc7a87d6245 |
| |
| CVE: CVE-2015-3197 |
| Signed-off-by: Armin Kuster <akuster@mvista.com> |
| |
| --- |
| ssl/s2_srvr.c | 15 +++++++++++++-- |
| 1 file changed, 13 insertions(+), 2 deletions(-) |
| |
| Index: openssl-1.0.2d/ssl/s2_srvr.c |
| =================================================================== |
| --- openssl-1.0.2d.orig/ssl/s2_srvr.c |
| +++ openssl-1.0.2d/ssl/s2_srvr.c |
| @@ -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); |
| @@ -687,8 +687,12 @@ 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--; |
| } |
| @@ -697,6 +701,13 @@ 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 |