-/* crypto/dh/dh_check.c */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
+/*
+ * Copyright 1995-2024 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 Apache License 2.0 (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
*/
+/*
+ * DH low level APIs are deprecated for public use, but still ok for
+ * internal use.
+ */
+#include "internal/deprecated.h"
+
#include <stdio.h>
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
#include <openssl/bn.h>
-#include <openssl/dh.h>
-
-/* Check that p is a safe prime and
- * if g is 2, 3 or 5, check that is is a suitable generator
- * where
- * for 2, p mod 24 == 11
- * for 3, p mod 12 == 5
- * for 5, p mod 10 == 3 or 7
- * should hold.
+#include "dh_local.h"
+#include "crypto/dh.h"
+
+/*-
+ * Check that p and g are suitable enough
+ *
+ * p is odd
+ * 1 < g < p - 1
*/
+int DH_check_params_ex(const DH *dh)
+{
+ int errflags = 0;
+
+ if (!DH_check_params(dh, &errflags))
+ return 0;
+
+ if ((errflags & DH_CHECK_P_NOT_PRIME) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_P_NOT_PRIME);
+ if ((errflags & DH_NOT_SUITABLE_GENERATOR) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_NOT_SUITABLE_GENERATOR);
+ if ((errflags & DH_MODULUS_TOO_SMALL) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_MODULUS_TOO_SMALL);
+ if ((errflags & DH_MODULUS_TOO_LARGE) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_MODULUS_TOO_LARGE);
+
+ return errflags == 0;
+}
+
+#ifdef FIPS_MODULE
+int DH_check_params(const DH *dh, int *ret)
+{
+ int nid;
+
+ *ret = 0;
+ /*
+ * SP800-56A R3 Section 5.5.2 Assurances of Domain Parameter Validity
+ * (1a) The domain parameters correspond to any approved safe prime group.
+ */
+ nid = DH_get_nid((DH *)dh);
+ if (nid != NID_undef)
+ return 1;
+ /*
+ * OR
+ * (2b) FFC domain params conform to FIPS-186-4 explicit domain param
+ * validity tests.
+ */
+ return ossl_ffc_params_FIPS186_4_validate(dh->libctx, &dh->params,
+ FFC_PARAM_TYPE_DH, ret, NULL);
+}
+#else
+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_ex(dh->libctx);
+ if (ctx == NULL)
+ goto err;
+ BN_CTX_start(ctx);
+ tmp = BN_CTX_get(ctx);
+ if (tmp == NULL)
+ goto err;
+
+ if (!BN_is_odd(dh->params.p))
+ *ret |= DH_CHECK_P_NOT_PRIME;
+ if (BN_is_negative(dh->params.g)
+ || BN_is_zero(dh->params.g)
+ || BN_is_one(dh->params.g))
+ *ret |= DH_NOT_SUITABLE_GENERATOR;
+ if (BN_copy(tmp, dh->params.p) == NULL || !BN_sub_word(tmp, 1))
+ goto err;
+ if (BN_cmp(dh->params.g, tmp) >= 0)
+ *ret |= DH_NOT_SUITABLE_GENERATOR;
+ if (BN_num_bits(dh->params.p) < DH_MIN_MODULUS_BITS)
+ *ret |= DH_MODULUS_TOO_SMALL;
+ if (BN_num_bits(dh->params.p) > OPENSSL_DH_MAX_MODULUS_BITS)
+ *ret |= DH_MODULUS_TOO_LARGE;
+
+ ok = 1;
+ err:
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ return ok;
+}
+#endif /* FIPS_MODULE */
+
+/*-
+ * Check that p is a safe prime and
+ * g is a suitable generator.
+ */
+int DH_check_ex(const DH *dh)
+{
+ int errflags = 0;
+
+ if (!DH_check(dh, &errflags))
+ return 0;
+
+ if ((errflags & DH_NOT_SUITABLE_GENERATOR) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_NOT_SUITABLE_GENERATOR);
+ if ((errflags & DH_CHECK_Q_NOT_PRIME) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_Q_NOT_PRIME);
+ if ((errflags & DH_CHECK_INVALID_Q_VALUE) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_INVALID_Q_VALUE);
+ if ((errflags & DH_CHECK_INVALID_J_VALUE) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_INVALID_J_VALUE);
+ if ((errflags & DH_UNABLE_TO_CHECK_GENERATOR) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_UNABLE_TO_CHECK_GENERATOR);
+ if ((errflags & DH_CHECK_P_NOT_PRIME) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_P_NOT_PRIME);
+ if ((errflags & DH_CHECK_P_NOT_SAFE_PRIME) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_P_NOT_SAFE_PRIME);
+ if ((errflags & DH_MODULUS_TOO_SMALL) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_MODULUS_TOO_SMALL);
+ if ((errflags & DH_MODULUS_TOO_LARGE) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_MODULUS_TOO_LARGE);
+
+ return errflags == 0;
+}
+
+/* Note: according to documentation - this only checks the params */
+int DH_check(const DH *dh, int *ret)
+{
+#ifdef FIPS_MODULE
+ return DH_check_params(dh, ret);
+#else
+ int ok = 0, r, q_good = 0;
+ BN_CTX *ctx = NULL;
+ BIGNUM *t1 = NULL, *t2 = NULL;
+ int nid = DH_get_nid((DH *)dh);
+
+ *ret = 0;
+ if (nid != NID_undef)
+ return 1;
+
+ /* Don't do any checks at all with an excessively large modulus */
+ if (BN_num_bits(dh->params.p) > OPENSSL_DH_CHECK_MAX_MODULUS_BITS) {
+ ERR_raise(ERR_LIB_DH, DH_R_MODULUS_TOO_LARGE);
+ *ret = DH_MODULUS_TOO_LARGE | DH_CHECK_P_NOT_PRIME;
+ return 0;
+ }
+
+ if (!DH_check_params(dh, ret))
+ return 0;
+
+ ctx = BN_CTX_new_ex(dh->libctx);
+ if (ctx == NULL)
+ goto err;
+ BN_CTX_start(ctx);
+ t1 = BN_CTX_get(ctx);
+ t2 = BN_CTX_get(ctx);
+ if (t2 == NULL)
+ goto err;
+
+ if (dh->params.q != NULL) {
+ if (BN_ucmp(dh->params.p, dh->params.q) > 0)
+ q_good = 1;
+ else
+ *ret |= DH_CHECK_INVALID_Q_VALUE;
+ }
-int DH_check(DH *dh, int *ret)
- {
- int ok=0;
- BN_CTX *ctx=NULL;
- BN_ULONG l;
- BIGNUM *q=NULL;
-
- *ret=0;
- ctx=BN_CTX_new();
- if (ctx == NULL) goto err;
- q=BN_new();
- if (q == NULL) goto err;
-
- if (BN_is_word(dh->g,DH_GENERATOR_2))
- {
- l=BN_mod_word(dh->p,24);
- 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;
- }
+ if (q_good) {
+ if (BN_cmp(dh->params.g, BN_value_one()) <= 0)
+ *ret |= DH_NOT_SUITABLE_GENERATOR;
+ else if (BN_cmp(dh->params.g, dh->params.p) >= 0)
+ *ret |= DH_NOT_SUITABLE_GENERATOR;
+ else {
+ /* Check g^q == 1 mod p */
+ if (!BN_mod_exp(t1, dh->params.g, dh->params.q, dh->params.p, ctx))
+ goto err;
+ if (!BN_is_one(t1))
+ *ret |= DH_NOT_SUITABLE_GENERATOR;
+ }
+ r = BN_check_prime(dh->params.q, 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->params.p, dh->params.q, ctx))
+ goto err;
+ if (!BN_is_one(t2))
+ *ret |= DH_CHECK_INVALID_Q_VALUE;
+ if (dh->params.j != NULL
+ && BN_cmp(dh->params.j, t1))
+ *ret |= DH_CHECK_INVALID_J_VALUE;
+ }
+
+ r = BN_check_prime(dh->params.p, ctx, NULL);
+ if (r < 0)
+ goto err;
+ if (!r)
+ *ret |= DH_CHECK_P_NOT_PRIME;
+ else if (dh->params.q == NULL) {
+ if (!BN_rshift1(t1, dh->params.p))
+ goto err;
+ r = BN_check_prime(t1, ctx, NULL);
+ if (r < 0)
+ goto err;
+ if (!r)
+ *ret |= DH_CHECK_P_NOT_SAFE_PRIME;
+ }
+ ok = 1;
+ err:
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ return ok;
+#endif /* FIPS_MODULE */
+}
+
+int DH_check_pub_key_ex(const DH *dh, const BIGNUM *pub_key)
+{
+ int errflags = 0;
+
+ if (!DH_check_pub_key(dh, pub_key, &errflags))
+ return 0;
+
+ if ((errflags & DH_CHECK_PUBKEY_TOO_SMALL) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_PUBKEY_TOO_SMALL);
+ if ((errflags & DH_CHECK_PUBKEY_TOO_LARGE) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_PUBKEY_TOO_LARGE);
+ if ((errflags & DH_CHECK_PUBKEY_INVALID) != 0)
+ ERR_raise(ERR_LIB_DH, DH_R_CHECK_PUBKEY_INVALID);
+
+ return errflags == 0;
+}
+
+/*
+ * See SP800-56Ar3 Section 5.6.2.3.1 : FFC Full public key validation.
+ */
+int DH_check_pub_key(const DH *dh, const BIGNUM *pub_key, int *ret)
+{
+ /* Don't do any checks at all with an excessively large modulus */
+ if (BN_num_bits(dh->params.p) > OPENSSL_DH_CHECK_MAX_MODULUS_BITS) {
+ ERR_raise(ERR_LIB_DH, DH_R_MODULUS_TOO_LARGE);
+ *ret = DH_MODULUS_TOO_LARGE | DH_CHECK_PUBKEY_INVALID;
+ return 0;
+ }
+
+ if (dh->params.q != NULL && BN_ucmp(dh->params.p, dh->params.q) < 0) {
+ *ret |= DH_CHECK_INVALID_Q_VALUE | DH_CHECK_PUBKEY_INVALID;
+ return 1;
+ }
+
+ return ossl_ffc_validate_public_key(&dh->params, pub_key, ret);
+}
+
+/*
+ * See SP800-56Ar3 Section 5.6.2.3.1 : FFC Partial public key validation.
+ * To only be used with ephemeral FFC public keys generated using the approved
+ * safe-prime groups.
+ */
+int ossl_dh_check_pub_key_partial(const DH *dh, const BIGNUM *pub_key, int *ret)
+{
+ return ossl_ffc_validate_public_key_partial(&dh->params, pub_key, ret)
+ && *ret == 0;
+}
+
+int ossl_dh_check_priv_key(const DH *dh, const BIGNUM *priv_key, int *ret)
+{
+ int ok = 0;
+ BIGNUM *two_powN = NULL, *upper;
+
+ *ret = 0;
+ two_powN = BN_new();
+ if (two_powN == NULL)
+ return 0;
+
+ if (dh->params.q != NULL) {
+ upper = dh->params.q;
+#ifndef FIPS_MODULE
+ } else if (dh->params.p != NULL) {
+ /*
+ * We do not have q so we just check the key is within some
+ * reasonable range, or the number of bits is equal to dh->length.
+ */
+ int length = dh->length;
+
+ if (length == 0) {
+ length = BN_num_bits(dh->params.p) - 1;
+ if (BN_num_bits(priv_key) <= length
+ && BN_num_bits(priv_key) > 1)
+ ok = 1;
+ } else if (BN_num_bits(priv_key) == length) {
+ ok = 1;
+ }
+ goto end;
#endif
- else if (BN_is_word(dh->g,DH_GENERATOR_5))
- {
- l=BN_mod_word(dh->p,10);
- if ((l != 3) && (l != 7))
- *ret|=DH_NOT_SUITABLE_GENERATOR;
- }
- else
- *ret|=DH_UNABLE_TO_CHECK_GENERATOR;
-
- if (!BN_is_prime(dh->p,BN_prime_checks,NULL,ctx,NULL))
- *ret|=DH_CHECK_P_NOT_PRIME;
- else
- {
- if (!BN_rshift1(q,dh->p)) goto err;
- if (!BN_is_prime(q,BN_prime_checks,NULL,ctx,NULL))
- *ret|=DH_CHECK_P_NOT_SAFE_PRIME;
- }
- ok=1;
+ } else {
+ goto end;
+ }
+
+ /* Is it from an approved Safe prime group ?*/
+ if (DH_get_nid((DH *)dh) != NID_undef && dh->length != 0) {
+ if (!BN_lshift(two_powN, BN_value_one(), dh->length))
+ goto end;
+ if (BN_cmp(two_powN, dh->params.q) < 0)
+ upper = two_powN;
+ }
+ if (!ossl_ffc_validate_private_key(upper, priv_key, ret))
+ goto end;
+
+ ok = 1;
+end:
+ BN_free(two_powN);
+ return ok;
+}
+
+/*
+ * FFC pairwise check from SP800-56A R3.
+ * Section 5.6.2.1.4 Owner Assurance of Pair-wise Consistency
+ */
+int ossl_dh_check_pairwise(const DH *dh)
+{
+ int ret = 0;
+ BN_CTX *ctx = NULL;
+ BIGNUM *pub_key = NULL;
+
+ if (dh->params.p == NULL
+ || dh->params.g == NULL
+ || dh->priv_key == NULL
+ || dh->pub_key == NULL)
+ return 0;
+
+ ctx = BN_CTX_new_ex(dh->libctx);
+ if (ctx == NULL)
+ goto err;
+ pub_key = BN_new();
+ if (pub_key == NULL)
+ goto err;
+
+ /* recalculate the public key = (g ^ priv) mod p */
+ if (!ossl_dh_generate_public_key(ctx, dh, dh->priv_key, pub_key))
+ goto err;
+ /* check it matches the existing public_key */
+ ret = BN_cmp(pub_key, dh->pub_key) == 0;
err:
- if (ctx != NULL) BN_CTX_free(ctx);
- if (q != NULL) BN_free(q);
- return(ok);
- }
+ BN_free(pub_key);
+ BN_CTX_free(ctx);
+ return ret;
+}
projects / openssl.git / blobdiff