[openssl-dev] [PATCH] logjam vulnerability changes for 0.9.8f version
Rao, Yarlagadda Srinivasa (MCOU)
yarlagadda-srinivasa.rao at hp.com
Thu Jun 11 13:57:31 UTC 2015
Hello All,
This patch fixes/back port the DH parameters changes from 1.0.1 stable branch to 0.9.8f version.
-----------------------------------------------------------------------------------
$ cat /tmp/patch.txt
--- s3_clnt.c_org 2015-06-10 14:27:54.000000000 +0530
+++ s3_clnt.c 2015-06-11 08:05:46.000000000 +0530
@@ -2575,22 +2575,31 @@
}
#endif
#ifndef OPENSSL_NO_DH
- if ((algs & SSL_kEDH) &&
- !(has_bits(i, EVP_PK_DH | EVP_PKT_EXCH) || (dh != NULL))) {
- SSLerr(SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM, SSL_R_MISSING_DH_KEY);
+ if ((algs & SSL_kEDH) && dh == NULL) {
+ SSLerr(SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM, ERR_R_INTERNAL_ERROR);
goto f_err;
- } else if ((algs & SSL_kDHr) && !has_bits(i, EVP_PK_DH | EVP_PKS_RSA)) {
+ }
+ if ((algs & SSL_kDHr) && !has_bits(i, EVP_PK_DH | EVP_PKS_RSA)) {
SSLerr(SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM,
SSL_R_MISSING_DH_RSA_CERT);
goto f_err;
}
# ifndef OPENSSL_NO_DSA
- else if ((algs & SSL_kDHd) && !has_bits(i, EVP_PK_DH | EVP_PKS_DSA)) {
+ if ((algs & SSL_kDHd) && !has_bits(i, EVP_PK_DH | EVP_PKS_DSA)) {
SSLerr(SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM,
SSL_R_MISSING_DH_DSA_CERT);
goto f_err;
}
# endif
+ /* Check DHE only: static DH not implemented. */
+ if (algs & SSL_kEDH) {
+ int dh_size = BN_num_bits(dh->p);
+ if ((!SSL_C_IS_EXPORT(s->s3->tmp.new_cipher) && dh_size < 768)
+ || (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher) && dh_size < 512)) {
+ SSLerr(SSL_F_SSL3_CHECK_CERT_AND_ALGORITHM, SSL_R_DH_KEY_TOO_SMALL);
+ goto f_err;
+ }
+ }
#endif
if (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher) && !has_bits(i, EVP_PKT_EXP)) {
--- ssl.h_org 2015-06-10 14:24:27.000000000 +0530
+++ ssl.h 2015-06-11 08:05:28.000000000 +0530
@@ -2036,6 +2036,7 @@
# define SSL_R_DATA_LENGTH_TOO_LONG 146
# define SSL_R_DECRYPTION_FAILED 147
# define SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC 281
+# define SSL_R_DH_KEY_TOO_SMALL 372
# define SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG 148
# define SSL_R_DIGEST_CHECK_FAILED 149
# define SSL_R_DTLS_MESSAGE_TOO_BIG 318
--- ssl_err.c_org 2015-06-10 14:21:03.000000000 +0530
+++ ssl_err.c 2015-06-11 08:05:21.000000000 +0530
@@ -390,6 +390,7 @@
{ERR_REASON(SSL_R_DECRYPTION_FAILED), "decryption failed"},
{ERR_REASON(SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC),
"decryption failed or bad record mac"},
+ {ERR_REASON(SSL_R_DH_KEY_TOO_SMALL), "dh key too small"},
{ERR_REASON(SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG),
"dh public value length is wrong"},
{ERR_REASON(SSL_R_DIGEST_CHECK_FAILED), "digest check failed"},
--- dhparam.c_org 2015-06-10 14:17:53.000000000 +0530
+++ dhparam.c 2015-06-11 08:04:47.000000000 +0530
@@ -130,7 +130,7 @@
# undef PROG
# define PROG dhparam_main
-# define DEFBITS 512
+# define DEFBITS 2048
/*-
* -inform arg - input format - default PEM (DER or PEM)
@@ -254,7 +254,7 @@
BIO_printf(bio_err,
" -5 generate parameters using 5 as the generator value\n");
BIO_printf(bio_err,
- " numbits number of bits in to generate (default 512)\n");
+ " numbits number of bits in to generate (default 2048)\n");
# ifndef OPENSSL_NO_ENGINE
BIO_printf(bio_err,
" -engine e use engine e, possibly a hardware device.\n");
--- gendh.c_org 2015-06-10 14:18:31.000000000 +0530
+++ gendh.c 2015-06-11 08:04:55.000000000 +0530
@@ -80,7 +80,7 @@
# include <openssl/x509.h>
# include <openssl/pem.h>
-# define DEFBITS 512
+# define DEFBITS 2048
# undef PROG
# define PROG gendh_main
--- s_server.c_org 2015-06-10 14:16:40.000000000 +0530
+++ s_server.c 2015-06-11 08:04:38.000000000 +0530
@@ -197,7 +197,7 @@
unsigned int *id_len);
#ifndef OPENSSL_NO_DH
static DH *load_dh_param(const char *dhfile);
-static DH *get_dh512(void);
+static DH *get_dh2048(void);
#endif
#ifdef MONOLITH
@@ -213,30 +213,48 @@
#endif
#ifndef OPENSSL_NO_DH
-static unsigned char dh512_p[] = {
- 0xDA, 0x58, 0x3C, 0x16, 0xD9, 0x85, 0x22, 0x89, 0xD0, 0xE4, 0xAF, 0x75,
- 0x6F, 0x4C, 0xCA, 0x92, 0xDD, 0x4B, 0xE5, 0x33, 0xB8, 0x04, 0xFB, 0x0F,
- 0xED, 0x94, 0xEF, 0x9C, 0x8A, 0x44, 0x03, 0xED, 0x57, 0x46, 0x50, 0xD3,
- 0x69, 0x99, 0xDB, 0x29, 0xD7, 0x76, 0x27, 0x6B, 0xA2, 0xD3, 0xD4, 0x12,
- 0xE2, 0x18, 0xF4, 0xDD, 0x1E, 0x08, 0x4C, 0xF6, 0xD8, 0x00, 0x3E, 0x7C,
- 0x47, 0x74, 0xE8, 0x33,
+static unsigned char dh2048_p[] = {
+ 0xF6,0x42,0x57,0xB7,0x08,0x7F,0x08,0x17,0x72,0xA2,0xBA,0xD6,
+ 0xA9,0x42,0xF3,0x05,0xE8,0xF9,0x53,0x11,0x39,0x4F,0xB6,0xF1,
+ 0x6E,0xB9,0x4B,0x38,0x20,0xDA,0x01,0xA7,0x56,0xA3,0x14,0xE9,
+ 0x8F,0x40,0x55,0xF3,0xD0,0x07,0xC6,0xCB,0x43,0xA9,0x94,0xAD,
+ 0xF7,0x4C,0x64,0x86,0x49,0xF8,0x0C,0x83,0xBD,0x65,0xE9,0x17,
+ 0xD4,0xA1,0xD3,0x50,0xF8,0xF5,0x59,0x5F,0xDC,0x76,0x52,0x4F,
+ 0x3D,0x3D,0x8D,0xDB,0xCE,0x99,0xE1,0x57,0x92,0x59,0xCD,0xFD,
+ 0xB8,0xAE,0x74,0x4F,0xC5,0xFC,0x76,0xBC,0x83,0xC5,0x47,0x30,
+ 0x61,0xCE,0x7C,0xC9,0x66,0xFF,0x15,0xF9,0xBB,0xFD,0x91,0x5E,
+ 0xC7,0x01,0xAA,0xD3,0x5B,0x9E,0x8D,0xA0,0xA5,0x72,0x3A,0xD4,
+ 0x1A,0xF0,0xBF,0x46,0x00,0x58,0x2B,0xE5,0xF4,0x88,0xFD,0x58,
+ 0x4E,0x49,0xDB,0xCD,0x20,0xB4,0x9D,0xE4,0x91,0x07,0x36,0x6B,
+ 0x33,0x6C,0x38,0x0D,0x45,0x1D,0x0F,0x7C,0x88,0xB3,0x1C,0x7C,
+ 0x5B,0x2D,0x8E,0xF6,0xF3,0xC9,0x23,0xC0,0x43,0xF0,0xA5,0x5B,
+ 0x18,0x8D,0x8E,0xBB,0x55,0x8C,0xB8,0x5D,0x38,0xD3,0x34,0xFD,
+ 0x7C,0x17,0x57,0x43,0xA3,0x1D,0x18,0x6C,0xDE,0x33,0x21,0x2C,
+ 0xB5,0x2A,0xFF,0x3C,0xE1,0xB1,0x29,0x40,0x18,0x11,0x8D,0x7C,
+ 0x84,0xA7,0x0A,0x72,0xD6,0x86,0xC4,0x03,0x19,0xC8,0x07,0x29,
+ 0x7A,0xCA,0x95,0x0C,0xD9,0x96,0x9F,0xAB,0xD0,0x0A,0x50,0x9B,
+ 0x02,0x46,0xD3,0x08,0x3D,0x66,0xA4,0x5D,0x41,0x9F,0x9C,0x7C,
+ 0xBD,0x89,0x4B,0x22,0x19,0x26,0xBA,0xAB,0xA2,0x5E,0xC3,0x55,
+ 0xE9,0x32,0x0B,0x3B,
};
-static unsigned char dh512_g[] = {
+static unsigned char dh2048_g[] = {
0x02,
};
-static DH *get_dh512(void)
+DH *get_dh2048(void)
{
- DH *dh = NULL;
+ DH *dh;
if ((dh = DH_new()) == NULL)
- return (NULL);
- dh->p = BN_bin2bn(dh512_p, sizeof(dh512_p), NULL);
- dh->g = BN_bin2bn(dh512_g, sizeof(dh512_g), NULL);
- if ((dh->p == NULL) || (dh->g == NULL))
- return (NULL);
- return (dh);
+ return NULL;
+ dh->p = BN_bin2bn(dh2048_p, sizeof(dh2048_p), NULL);
+ dh->g = BN_bin2bn(dh2048_g, sizeof(dh2048_g), NULL);
+ if (dh->p == NULL || dh->g == NULL) {
+ DH_free(dh);
+ return NULL;
+ }
+ return dh;
}
#endif
@@ -1343,7 +1361,11 @@
BIO_printf(bio_s_out, "Setting temp DH parameters\n");
} else {
BIO_printf(bio_s_out, "Using default temp DH parameters\n");
- dh = get_dh512();
+ dh = get_dh2048();
+ if (dh == NULL) {
+ ERR_print_errors(bio_err);
+ goto end;
+ }
}
(void)BIO_flush(bio_s_out);
$
---------------------------------------------------------------------
After applying the above patch to 0.9.8f, I could find the following o/p from the test logs.
Step-1: Generate DH parameters with 767 and 512 bits.
openssl dhparam -out dh767.pem 767
openssl dhparam -out dh512.pem 512
Step-2: Start openssl s_server with the above created DH parameters.
openssl s_server -dhparam dh767.pem -accept 1234 -cert server.crt -key server.key
Step-3: connect s_client to the above server
openssl s_client -connect x.x.x.x:1234
Following error shows in the s_client side:
20422:error:14082174:SSL routines:SSL3_CHECK_CERT_AND_ALGORITHM:dh key too small:s3_clnt.c:2599:
And from s_server side shows following error message.
ERROR
23019:error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure:s3_pkt.c:1143:SSL alert number 40
shutting down SSL
Step-4: start s_server with DH parameters more than 767 bits (Example 1024 and 768)
openssl s_server -dhparam dh1024.pem -accept 1234 -cert server.crt -key server.key
Step-5: connect s_client to the above server
The connection succeeds without any error messages.
>From the above test logs, It looks like the changes are working fine.
Can someone help me to validate the changes?
If the changes are fine, then I can submit the same changes to 0.9.8 stable branch. So that it will be available in the next release.
Thanks & Regards,
Vasu
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