-/* crypto/dh/dh_check.c */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
+/*
+ * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
*
- * This package is an SSL implementation written
- * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
- *
- * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to. The following conditions
- * apply to all code found in this distribution, be it the RC4, RSA,
- * lhash, DES, etc., code; not just the SSL code. The SSL documentation
- * included with this distribution is covered by the same copyright terms
- * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- *
- * Copyright remains Eric Young's, and as such any Copyright notices in
- * the code are not to be removed.
- * If this package is used in a product, Eric Young should be given attribution
- * as the author of the parts of the library used.
- * This can be in the form of a textual message at program startup or
- * in documentation (online or textual) provided with the package.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * "This product includes cryptographic software written by
- * Eric Young (eay@cryptsoft.com)"
- * The word 'cryptographic' can be left out if the rouines from the library
- * being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from
- * the apps directory (application code) you must include an acknowledgement:
- * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- *
- * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * The licence and distribution terms for any publically available version or
- * derivative of this code cannot be changed. i.e. this code cannot simply be
- * copied and put under another distribution licence
- * [including the GNU Public Licence.]
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
*/
#include <stdio.h>
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
#include <openssl/bn.h>
-#include <openssl/dh.h>
+#include "dh_locl.h"
+
+/*-
+ * Check that p and g are suitable enough
+ *
+ * p is odd
+ * 1 < g < p - 1
+ */
+
+int DH_check_params(const DH *dh, int *ret)
+{
+ int ok = 0;
+ BIGNUM *tmp = NULL;
+ BN_CTX *ctx = NULL;
+
+ *ret = 0;
+ ctx = BN_CTX_new();
+ if (ctx == NULL)
+ goto err;
+ BN_CTX_start(ctx);
+ tmp = BN_CTX_get(ctx);
+ if (tmp == NULL)
+ goto err;
+
+ if (!BN_is_odd(dh->p))
+ *ret |= DH_CHECK_P_NOT_PRIME;
+ if (BN_is_negative(dh->g) || BN_is_zero(dh->g) || BN_is_one(dh->g))
+ *ret |= DH_NOT_SUITABLE_GENERATOR;
+ if (BN_copy(tmp, dh->p) == NULL || !BN_sub_word(tmp, 1))
+ goto err;
+ if (BN_cmp(dh->g, tmp) >= 0)
+ *ret |= DH_NOT_SUITABLE_GENERATOR;
+
+ ok = 1;
+ err:
+ if (ctx != NULL) {
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ }
+ return (ok);
+}
/*-
* Check that p is a safe prime and
int DH_check(const DH *dh, int *ret)
{
- int ok = 0;
+ int ok = 0, r;
BN_CTX *ctx = NULL;
BN_ULONG l;
BIGNUM *t1 = NULL, *t2 = NULL;
goto err;
BN_CTX_start(ctx);
t1 = BN_CTX_get(ctx);
- if (t1 == NULL)
- goto err;
t2 = BN_CTX_get(ctx);
if (t2 == NULL)
goto err;
if (!BN_is_one(t1))
*ret |= DH_NOT_SUITABLE_GENERATOR;
}
- if (!BN_is_prime_ex(dh->q, BN_prime_checks, ctx, NULL))
+ r = BN_is_prime_ex(dh->q, BN_prime_checks, ctx, NULL);
+ if (r < 0)
+ goto err;
+ if (!r)
*ret |= DH_CHECK_Q_NOT_PRIME;
/* Check p == 1 mod q i.e. q divides p - 1 */
if (!BN_div(t1, t2, dh->p, dh->q, ctx))
} else if (BN_is_word(dh->g, DH_GENERATOR_2)) {
l = BN_mod_word(dh->p, 24);
+ if (l == (BN_ULONG)-1)
+ goto err;
if (l != 11)
*ret |= DH_NOT_SUITABLE_GENERATOR;
- }
-#if 0
- else if (BN_is_word(dh->g, DH_GENERATOR_3)) {
- l = BN_mod_word(dh->p, 12);
- if (l != 5)
- *ret |= DH_NOT_SUITABLE_GENERATOR;
- }
-#endif
- else if (BN_is_word(dh->g, DH_GENERATOR_5)) {
+ } else if (BN_is_word(dh->g, DH_GENERATOR_5)) {
l = BN_mod_word(dh->p, 10);
+ if (l == (BN_ULONG)-1)
+ goto err;
if ((l != 3) && (l != 7))
*ret |= DH_NOT_SUITABLE_GENERATOR;
} else
*ret |= DH_UNABLE_TO_CHECK_GENERATOR;
- if (!BN_is_prime_ex(dh->p, BN_prime_checks, ctx, NULL))
+ r = BN_is_prime_ex(dh->p, BN_prime_checks, ctx, NULL);
+ if (r < 0)
+ goto err;
+ if (!r)
*ret |= DH_CHECK_P_NOT_PRIME;
else if (!dh->q) {
if (!BN_rshift1(t1, dh->p))
goto err;
- if (!BN_is_prime_ex(t1, BN_prime_checks, ctx, NULL))
+ r = BN_is_prime_ex(t1, BN_prime_checks, ctx, NULL);
+ if (r < 0)
+ goto err;
+ if (!r)
*ret |= DH_CHECK_P_NOT_SAFE_PRIME;
}
ok = 1;
int DH_check_pub_key(const DH *dh, const BIGNUM *pub_key, int *ret)
{
int ok = 0;
- BIGNUM *q = NULL;
+ BIGNUM *tmp = NULL;
+ BN_CTX *ctx = NULL;
*ret = 0;
- q = BN_new();
- if (q == NULL)
+ ctx = BN_CTX_new();
+ if (ctx == NULL)
goto err;
- BN_set_word(q, 1);
- if (BN_cmp(pub_key, q) <= 0)
+ BN_CTX_start(ctx);
+ tmp = BN_CTX_get(ctx);
+ if (tmp == NULL || !BN_set_word(tmp, 1))
+ goto err;
+ if (BN_cmp(pub_key, tmp) <= 0)
*ret |= DH_CHECK_PUBKEY_TOO_SMALL;
- BN_copy(q, dh->p);
- BN_sub_word(q, 1);
- if (BN_cmp(pub_key, q) >= 0)
+ if (BN_copy(tmp, dh->p) == NULL || !BN_sub_word(tmp, 1))
+ goto err;
+ if (BN_cmp(pub_key, tmp) >= 0)
*ret |= DH_CHECK_PUBKEY_TOO_LARGE;
+ if (dh->q != NULL) {
+ /* Check pub_key^q == 1 mod p */
+ if (!BN_mod_exp(tmp, pub_key, dh->q, dh->p, ctx))
+ goto err;
+ if (!BN_is_one(tmp))
+ *ret |= DH_CHECK_PUBKEY_INVALID;
+ }
+
ok = 1;
err:
- if (q != NULL)
- BN_free(q);
+ if (ctx != NULL) {
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ }
return (ok);
}
projects / openssl.git / blobdiff