[src/trunk]: src/crypto/external/bsd/openssl/dist/ssl pull in rev.22050 from ...

[drochner <drochner%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0b466b41cfbd
branches:  trunk
changeset: 772856:0b466b41cfbd
user:      drochner <drochner%NetBSD.org@localhost>
date:      Wed Jan 18 20:08:49 2012 +0000

description:
pull in rev.22050 from upstream CVS, following secadv_20120118.txt:
Fix for DTLS DoS issue introduced by fix for CVE-2011-4108 (CVE-2012-0050)

diffstat:

 crypto/external/bsd/openssl/dist/ssl/d1_pkt.c |  17 +++++++----------
 1 files changed, 7 insertions(+), 10 deletions(-)

diffs (37 lines):

diff -r aaf65c7ec3cd -r 0b466b41cfbd crypto/external/bsd/openssl/dist/ssl/d1_pkt.c
--- a/crypto/external/bsd/openssl/dist/ssl/d1_pkt.c     Wed Jan 18 19:17:02 2012 +0000
+++ b/crypto/external/bsd/openssl/dist/ssl/d1_pkt.c     Wed Jan 18 20:08:49 2012 +0000
@@ -376,6 +376,7 @@
        unsigned int mac_size;
        unsigned char md[EVP_MAX_MD_SIZE];
        int decryption_failed_or_bad_record_mac = 0;
+       unsigned char *mac = NULL;
 
 
        rr= &(s->s3->rrec);
@@ -450,19 +451,15 @@
 #endif                 
                        }
                /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
-               if (rr->length < mac_size)
+               if (rr->length >= mac_size)
                        {
-#if 0 /* OK only for stream ciphers */
-                       al=SSL_AD_DECODE_ERROR;
-                       SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
-                       goto f_err;
-#else
-                       decryption_failed_or_bad_record_mac = 1;
-#endif
+                       rr->length -= mac_size;
+                       mac = &rr->data[rr->length];
                        }
-               rr->length-=mac_size;
+               else
+                       rr->length = 0;
                i=s->method->ssl3_enc->mac(s,md,0);
-               if (i < 0 || memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
+               if (i < 0 || mac == NULL || memcmp(md, mac, mac_size) != 0)
                        {
                        decryption_failed_or_bad_record_mac = 1;
                        }