xref: /freebsd/crypto/openssl/crypto/dsa/dsa_check.c (revision b077aed33b7b6aefca7b17ddb250cf521f938613)
1*b077aed3SPierre Pronchery /*
2*b077aed3SPierre Pronchery  * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
3*b077aed3SPierre Pronchery  *
4*b077aed3SPierre Pronchery  * Licensed under the Apache License 2.0 (the "License").  You may not use
5*b077aed3SPierre Pronchery  * this file except in compliance with the License.  You can obtain a copy
6*b077aed3SPierre Pronchery  * in the file LICENSE in the source distribution or at
7*b077aed3SPierre Pronchery  * https://www.openssl.org/source/license.html
8*b077aed3SPierre Pronchery  */
9*b077aed3SPierre Pronchery 
10*b077aed3SPierre Pronchery /*
11*b077aed3SPierre Pronchery  * DSA low level APIs are deprecated for public use, but still ok for
12*b077aed3SPierre Pronchery  * internal use.
13*b077aed3SPierre Pronchery  */
14*b077aed3SPierre Pronchery #include "internal/deprecated.h"
15*b077aed3SPierre Pronchery 
16*b077aed3SPierre Pronchery #include <stdio.h>
17*b077aed3SPierre Pronchery #include "internal/cryptlib.h"
18*b077aed3SPierre Pronchery #include <openssl/bn.h>
19*b077aed3SPierre Pronchery #include "dsa_local.h"
20*b077aed3SPierre Pronchery #include "crypto/dsa.h"
21*b077aed3SPierre Pronchery 
22*b077aed3SPierre Pronchery int ossl_dsa_check_params(const DSA *dsa, int checktype, int *ret)
23*b077aed3SPierre Pronchery {
24*b077aed3SPierre Pronchery     if (checktype == OSSL_KEYMGMT_VALIDATE_QUICK_CHECK)
25*b077aed3SPierre Pronchery         return ossl_ffc_params_simple_validate(dsa->libctx, &dsa->params,
26*b077aed3SPierre Pronchery                                                FFC_PARAM_TYPE_DSA, ret);
27*b077aed3SPierre Pronchery     else
28*b077aed3SPierre Pronchery         /*
29*b077aed3SPierre Pronchery          * Do full FFC domain params validation according to FIPS-186-4
30*b077aed3SPierre Pronchery          *  - always in FIPS_MODULE
31*b077aed3SPierre Pronchery          *  - only if possible (i.e., seed is set) in default provider
32*b077aed3SPierre Pronchery          */
33*b077aed3SPierre Pronchery         return ossl_ffc_params_full_validate(dsa->libctx, &dsa->params,
34*b077aed3SPierre Pronchery                                              FFC_PARAM_TYPE_DSA, ret);
35*b077aed3SPierre Pronchery }
36*b077aed3SPierre Pronchery 
37*b077aed3SPierre Pronchery /*
38*b077aed3SPierre Pronchery  * See SP800-56Ar3 Section 5.6.2.3.1 : FFC Full public key validation.
39*b077aed3SPierre Pronchery  */
40*b077aed3SPierre Pronchery int ossl_dsa_check_pub_key(const DSA *dsa, const BIGNUM *pub_key, int *ret)
41*b077aed3SPierre Pronchery {
42*b077aed3SPierre Pronchery     return ossl_ffc_validate_public_key(&dsa->params, pub_key, ret);
43*b077aed3SPierre Pronchery }
44*b077aed3SPierre Pronchery 
45*b077aed3SPierre Pronchery /*
46*b077aed3SPierre Pronchery  * See SP800-56Ar3 Section 5.6.2.3.1 : FFC Partial public key validation.
47*b077aed3SPierre Pronchery  * To only be used with ephemeral FFC public keys generated using the approved
48*b077aed3SPierre Pronchery  * safe-prime groups.
49*b077aed3SPierre Pronchery  */
50*b077aed3SPierre Pronchery int ossl_dsa_check_pub_key_partial(const DSA *dsa, const BIGNUM *pub_key, int *ret)
51*b077aed3SPierre Pronchery {
52*b077aed3SPierre Pronchery     return ossl_ffc_validate_public_key_partial(&dsa->params, pub_key, ret);
53*b077aed3SPierre Pronchery }
54*b077aed3SPierre Pronchery 
55*b077aed3SPierre Pronchery int ossl_dsa_check_priv_key(const DSA *dsa, const BIGNUM *priv_key, int *ret)
56*b077aed3SPierre Pronchery {
57*b077aed3SPierre Pronchery     *ret = 0;
58*b077aed3SPierre Pronchery 
59*b077aed3SPierre Pronchery     return (dsa->params.q != NULL
60*b077aed3SPierre Pronchery             && ossl_ffc_validate_private_key(dsa->params.q, priv_key, ret));
61*b077aed3SPierre Pronchery }
62*b077aed3SPierre Pronchery 
63*b077aed3SPierre Pronchery /*
64*b077aed3SPierre Pronchery  * FFC pairwise check from SP800-56A R3.
65*b077aed3SPierre Pronchery  *    Section 5.6.2.1.4 Owner Assurance of Pair-wise Consistency
66*b077aed3SPierre Pronchery  */
67*b077aed3SPierre Pronchery int ossl_dsa_check_pairwise(const DSA *dsa)
68*b077aed3SPierre Pronchery {
69*b077aed3SPierre Pronchery     int ret = 0;
70*b077aed3SPierre Pronchery     BN_CTX *ctx = NULL;
71*b077aed3SPierre Pronchery     BIGNUM *pub_key = NULL;
72*b077aed3SPierre Pronchery 
73*b077aed3SPierre Pronchery     if (dsa->params.p == NULL
74*b077aed3SPierre Pronchery         || dsa->params.g == NULL
75*b077aed3SPierre Pronchery         || dsa->priv_key == NULL
76*b077aed3SPierre Pronchery         || dsa->pub_key == NULL)
77*b077aed3SPierre Pronchery         return 0;
78*b077aed3SPierre Pronchery 
79*b077aed3SPierre Pronchery     ctx = BN_CTX_new_ex(dsa->libctx);
80*b077aed3SPierre Pronchery     if (ctx == NULL)
81*b077aed3SPierre Pronchery         goto err;
82*b077aed3SPierre Pronchery     pub_key = BN_new();
83*b077aed3SPierre Pronchery     if (pub_key == NULL)
84*b077aed3SPierre Pronchery         goto err;
85*b077aed3SPierre Pronchery 
86*b077aed3SPierre Pronchery     /* recalculate the public key = (g ^ priv) mod p */
87*b077aed3SPierre Pronchery     if (!ossl_dsa_generate_public_key(ctx, dsa, dsa->priv_key, pub_key))
88*b077aed3SPierre Pronchery         goto err;
89*b077aed3SPierre Pronchery     /* check it matches the existing pubic_key */
90*b077aed3SPierre Pronchery     ret = BN_cmp(pub_key, dsa->pub_key) == 0;
91*b077aed3SPierre Pronchery err:
92*b077aed3SPierre Pronchery     BN_free(pub_key);
93*b077aed3SPierre Pronchery     BN_CTX_free(ctx);
94*b077aed3SPierre Pronchery     return ret;
95*b077aed3SPierre Pronchery }
96