Commit 855d2918 authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

Fix for DTLS DoS issue introduced by fix for CVE-2011-4109.

Thanks to Antonio Martin, Enterprise Secure Access Research and
Development, Cisco Systems, Inc. for discovering this bug and
preparing a fix. (CVE-2012-0050)
parent ac07bc86
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+16 −0
Original line number Diff line number Diff line
@@ -522,6 +522,14 @@
       Add command line options to s_client/s_server.
     [Steve Henson]

 Changes between 1.0.0f and 1.0.0g [18 Jan 2012]

  *) Fix for DTLS DoS issue introduced by fix for CVE-2011-4109.
     Thanks to Antonio Martin, Enterprise Secure Access Research and
     Development, Cisco Systems, Inc. for discovering this bug and
     preparing a fix. (CVE-2012-0050)
     [Antonio Martin]

 Changes between 1.0.0e and 1.0.0f [4 Jan 2012]

  *) Nadhem Alfardan and Kenny Paterson have discovered an extension
@@ -1486,6 +1494,14 @@
  *) Change 'Configure' script to enable Camellia by default.
     [NTT]

 Changes between 0.9.8s and 0.9.8t [18 Jan 2012]

  *) Fix for DTLS DoS issue introduced by fix for CVE-2011-4109.
     Thanks to Antonio Martin, Enterprise Secure Access Research and
     Development, Cisco Systems, Inc. for discovering this bug and
     preparing a fix. (CVE-2012-0050)
     [Antonio Martin]
  
 Changes between 0.9.8r and 0.9.8s [4 Jan 2012]

  *) Nadhem Alfardan and Kenny Paterson have discovered an extension
+1 −1
Original line number Diff line number Diff line
@@ -2056,7 +2056,7 @@ static void print_stuff(BIO *bio, SSL *s, int full)
	}
#endif

#ifdef SSL_DEBUG
#if 1
	{
	/* Print out local port of connection: useful for debugging */
	int sock;
+7 −10
Original line number Diff line number Diff line
@@ -384,6 +384,7 @@ dtls1_process_record(SSL *s)
	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);
@@ -455,19 +456,15 @@ printf("\n");
#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];
			}
		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;
			}