/src/openssl/crypto/dsa/dsa_pmeth.c

Source
/*
 * Copyright 2006-2025 The OpenSSL Project Authors. All Rights Reserved.
 *
 * 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
 */

/*
 * DSA low level APIs are deprecated for public use, but still ok for
 * internal use.
 */
#include "internal/deprecated.h"

#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/asn1t.h>
#include <openssl/x509.h>
#include <openssl/evp.h>
#include <openssl/bn.h>
#include "crypto/evp.h"
#include "dsa_local.h"

/* DSA pkey context structure */

typedef struct {
    /* Parameter gen parameters */
    int nbits; /* size of p in bits (default: 2048) */
    int qbits; /* size of q in bits (default: 224) */
    const EVP_MD *pmd; /* MD for parameter generation */
    /* Keygen callback info */
    int gentmp[2];
    /* message digest */
    const EVP_MD *md; /* MD for the signature */
} DSA_PKEY_CTX;

static int pkey_dsa_init(EVP_PKEY_CTX *ctx)
{
    DSA_PKEY_CTX *dctx = OPENSSL_malloc(sizeof(*dctx));

    if (dctx == NULL)
        return 0;
    dctx->nbits = 2048;
    dctx->qbits = 224;
    dctx->pmd = NULL;
    dctx->md = NULL;

    ctx->data = dctx;
    ctx->keygen_info = dctx->gentmp;
    ctx->keygen_info_count = 2;

    return 1;
}

static int pkey_dsa_copy(EVP_PKEY_CTX *dst, const EVP_PKEY_CTX *src)
{
    DSA_PKEY_CTX *dctx, *sctx;

    if (!pkey_dsa_init(dst))
        return 0;
    sctx = src->data;
    dctx = dst->data;
    dctx->nbits = sctx->nbits;
    dctx->qbits = sctx->qbits;
    dctx->pmd = sctx->pmd;
    dctx->md = sctx->md;
    return 1;
}

static void pkey_dsa_cleanup(EVP_PKEY_CTX *ctx)
{
    DSA_PKEY_CTX *dctx = ctx->data;
    OPENSSL_free(dctx);
}

static int pkey_dsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
    size_t *siglen, const unsigned char *tbs,
    size_t tbslen)
{
    int ret, md_size;
    unsigned int sltmp;
    DSA_PKEY_CTX *dctx = ctx->data;
    /*
     * Discard const. Its marked as const because this may be a cached copy of
     * the "real" key. These calls don't make any modifications that need to
     * be reflected back in the "original" key.
     */
    DSA *dsa = (DSA *)EVP_PKEY_get0_DSA(ctx->pkey);

    if (dctx->md != NULL) {
        md_size = EVP_MD_get_size(dctx->md);
        if (md_size <= 0)
            return 0;
        if (tbslen != (size_t)md_size)
            return 0;
    }

    ret = DSA_sign(0, tbs, (int)tbslen, sig, &sltmp, dsa);

    if (ret <= 0)
        return ret;
    *siglen = sltmp;
    return 1;
}

static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
    const unsigned char *sig, size_t siglen,
    const unsigned char *tbs, size_t tbslen)
{
    int ret, md_size;
    DSA_PKEY_CTX *dctx = ctx->data;
    /*
     * Discard const. Its marked as const because this may be a cached copy of
     * the "real" key. These calls don't make any modifications that need to
     * be reflected back in the "original" key.
     */
    DSA *dsa = (DSA *)EVP_PKEY_get0_DSA(ctx->pkey);

    if (dctx->md != NULL) {
        md_size = EVP_MD_get_size(dctx->md);
        if (md_size <= 0)
            return 0;
        if (tbslen != (size_t)md_size)
            return 0;
    }

    ret = DSA_verify(0, tbs, (int)tbslen, sig, (int)siglen, dsa);

    return ret;
}

static int pkey_dsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
{
    DSA_PKEY_CTX *dctx = ctx->data;

    switch (type) {
    case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS:
        if (p1 < 256)
            return -2;
        dctx->nbits = p1;
        return 1;

    case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS:
        if (p1 != 160 && p1 != 224 && p1 && p1 != 256)
            return -2;
        dctx->qbits = p1;
        return 1;

    case EVP_PKEY_CTRL_DSA_PARAMGEN_MD:
        if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256) {
            ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
            return 0;
        }
        dctx->pmd = p2;
        return 1;

    case EVP_PKEY_CTRL_MD:
        if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 && EVP_MD_get_type((const EVP_MD *)p2) != NID_dsa && EVP_MD_get_type((const EVP_MD *)p2) != NID_dsaWithSHA && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha384 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha512 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_224 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_256 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_384 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_512) {
            ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
            return 0;
        }
        dctx->md = p2;
        return 1;

    case EVP_PKEY_CTRL_GET_MD:
        *(const EVP_MD **)p2 = dctx->md;
        return 1;

    case EVP_PKEY_CTRL_DIGESTINIT:
    case EVP_PKEY_CTRL_PKCS7_SIGN:
    case EVP_PKEY_CTRL_CMS_SIGN:
        return 1;

    case EVP_PKEY_CTRL_PEER_KEY:
        ERR_raise(ERR_LIB_DSA, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
        return -2;
    default:
        return -2;
    }
}

static int pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx,
    const char *type, const char *value)
{
    if (strcmp(type, "dsa_paramgen_bits") == 0) {
        int nbits;
        nbits = atoi(value);
        return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits);
    }
    if (strcmp(type, "dsa_paramgen_q_bits") == 0) {
        int qbits = atoi(value);
        return EVP_PKEY_CTX_set_dsa_paramgen_q_bits(ctx, qbits);
    }
    if (strcmp(type, "dsa_paramgen_md") == 0) {
        const EVP_MD *md = EVP_get_digestbyname(value);

        if (md == NULL) {
            ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
            return 0;
        }
        return EVP_PKEY_CTX_set_dsa_paramgen_md(ctx, md);
    }
    return -2;
}

static int pkey_dsa_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
    DSA *dsa = NULL;
    DSA_PKEY_CTX *dctx = ctx->data;
    BN_GENCB *pcb;
    int ret, res;

    if (ctx->pkey_gencb) {
        pcb = BN_GENCB_new();
        if (pcb == NULL)
            return 0;
        evp_pkey_set_cb_translate(pcb, ctx);
    } else
        pcb = NULL;
    dsa = DSA_new();
    if (dsa == NULL) {
        BN_GENCB_free(pcb);
        return 0;
    }
    if (dctx->md != NULL)
        ossl_ffc_set_digest(&dsa->params, EVP_MD_get0_name(dctx->md), NULL);

    ret = ossl_ffc_params_FIPS186_4_generate(NULL, &dsa->params,
        FFC_PARAM_TYPE_DSA, dctx->nbits,
        dctx->qbits, &res, pcb);
    BN_GENCB_free(pcb);
    if (ret > 0)
        EVP_PKEY_assign_DSA(pkey, dsa);
    else
        DSA_free(dsa);
    return ret;
}

static int pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
    DSA *dsa = NULL;

    if (ctx->pkey == NULL) {
        ERR_raise(ERR_LIB_DSA, DSA_R_NO_PARAMETERS_SET);
        return 0;
    }
    dsa = DSA_new();
    if (dsa == NULL)
        return 0;
    EVP_PKEY_assign_DSA(pkey, dsa);
    /* Note: if error return, pkey is freed by parent routine */
    if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
        return 0;
    return DSA_generate_key((DSA *)EVP_PKEY_get0_DSA(pkey));
}

static const EVP_PKEY_METHOD dsa_pkey_meth = {
    EVP_PKEY_DSA,
    EVP_PKEY_FLAG_AUTOARGLEN,
    pkey_dsa_init,
    pkey_dsa_copy,
    pkey_dsa_cleanup,

    0,
    pkey_dsa_paramgen,

    0,
    pkey_dsa_keygen,

    0,
    pkey_dsa_sign,

    0,
    pkey_dsa_verify,

    0, 0,

    0, 0, 0, 0,

    0, 0,

    0, 0,

    0, 0,

    pkey_dsa_ctrl,
    pkey_dsa_ctrl_str
};

const EVP_PKEY_METHOD *ossl_dsa_pkey_method(void)
{
    return &dsa_pkey_meth;
}

Coverage Report

Created: 2025-12-10 06:24

Line	Count	Source
1		/*
2		* Copyright 2006-2025 The OpenSSL Project Authors. All Rights Reserved.
3		*
4		* Licensed under the Apache License 2.0 (the "License"). You may not use
5		* this file except in compliance with the License. You can obtain a copy
6		* in the file LICENSE in the source distribution or at
7		* https://www.openssl.org/source/license.html
8		*/
9
10		/*
11		* DSA low level APIs are deprecated for public use, but still ok for
12		* internal use.
13		*/
14		#include "internal/deprecated.h"
15
16		#include <stdio.h>
17		#include "internal/cryptlib.h"
18		#include <openssl/asn1t.h>
19		#include <openssl/x509.h>
20		#include <openssl/evp.h>
21		#include <openssl/bn.h>
22		#include "crypto/evp.h"
23		#include "dsa_local.h"
24
25		/* DSA pkey context structure */
26
27		typedef struct {
28		/* Parameter gen parameters */
29		int nbits; /* size of p in bits (default: 2048) */
30		int qbits; /* size of q in bits (default: 224) */
31		const EVP_MD pmd; / MD for parameter generation */
32		/* Keygen callback info */
33		int gentmp[2];
34		/* message digest */
35		const EVP_MD md; / MD for the signature */
36		} DSA_PKEY_CTX;
37
38		static int pkey_dsa_init(EVP_PKEY_CTX *ctx)
39	0	{
40	0	DSA_PKEY_CTX dctx = OPENSSL_malloc(sizeof(dctx));
41
42	0	if (dctx == NULL)
43	0	return 0;
44	0	dctx->nbits = 2048;
45	0	dctx->qbits = 224;
46	0	dctx->pmd = NULL;
47	0	dctx->md = NULL;
48
49	0	ctx->data = dctx;
50	0	ctx->keygen_info = dctx->gentmp;
51	0	ctx->keygen_info_count = 2;
52
53	0	return 1;
54	0	}
55
56		static int pkey_dsa_copy(EVP_PKEY_CTX dst, const EVP_PKEY_CTX src)
57	0	{
58	0	DSA_PKEY_CTX dctx, sctx;
59
60	0	if (!pkey_dsa_init(dst))
61	0	return 0;
62	0	sctx = src->data;
63	0	dctx = dst->data;
64	0	dctx->nbits = sctx->nbits;
65	0	dctx->qbits = sctx->qbits;
66	0	dctx->pmd = sctx->pmd;
67	0	dctx->md = sctx->md;
68	0	return 1;
69	0	}
70
71		static void pkey_dsa_cleanup(EVP_PKEY_CTX *ctx)
72	0	{
73	0	DSA_PKEY_CTX *dctx = ctx->data;
74	0	OPENSSL_free(dctx);
75	0	}
76
77		static int pkey_dsa_sign(EVP_PKEY_CTX ctx, unsigned char sig,
78		size_t siglen, const unsigned char tbs,
79		size_t tbslen)
80	0	{
81	0	int ret, md_size;
82	0	unsigned int sltmp;
83	0	DSA_PKEY_CTX *dctx = ctx->data;
84		/*
85		* Discard const. Its marked as const because this may be a cached copy of
86		* the "real" key. These calls don't make any modifications that need to
87		* be reflected back in the "original" key.
88		*/
89	0	DSA dsa = (DSA )EVP_PKEY_get0_DSA(ctx->pkey);
90
91	0	if (dctx->md != NULL) {
92	0	md_size = EVP_MD_get_size(dctx->md);
93	0	if (md_size <= 0)
94	0	return 0;
95	0	if (tbslen != (size_t)md_size)
96	0	return 0;
97	0	}
98
99	0	ret = DSA_sign(0, tbs, (int)tbslen, sig, &sltmp, dsa);
100
101	0	if (ret <= 0)
102	0	return ret;
103	0	*siglen = sltmp;
104	0	return 1;
105	0	}
106
107		static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
108		const unsigned char *sig, size_t siglen,
109		const unsigned char *tbs, size_t tbslen)
110	0	{
111	0	int ret, md_size;
112	0	DSA_PKEY_CTX *dctx = ctx->data;
113		/*
114		* Discard const. Its marked as const because this may be a cached copy of
115		* the "real" key. These calls don't make any modifications that need to
116		* be reflected back in the "original" key.
117		*/
118	0	DSA dsa = (DSA )EVP_PKEY_get0_DSA(ctx->pkey);
119
120	0	if (dctx->md != NULL) {
121	0	md_size = EVP_MD_get_size(dctx->md);
122	0	if (md_size <= 0)
123	0	return 0;
124	0	if (tbslen != (size_t)md_size)
125	0	return 0;
126	0	}
127
128	0	ret = DSA_verify(0, tbs, (int)tbslen, sig, (int)siglen, dsa);
129
130	0	return ret;
131	0	}
132
133		static int pkey_dsa_ctrl(EVP_PKEY_CTX ctx, int type, int p1, void p2)
134	0	{
135	0	DSA_PKEY_CTX *dctx = ctx->data;
136
137	0	switch (type) {
138	0	case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS:
139	0	if (p1 < 256)
140	0	return -2;
141	0	dctx->nbits = p1;
142	0	return 1;
143
144	0	case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS:
145	0	if (p1 != 160 && p1 != 224 && p1 && p1 != 256)
146	0	return -2;
147	0	dctx->qbits = p1;
148	0	return 1;
149
150	0	case EVP_PKEY_CTRL_DSA_PARAMGEN_MD:
151	0	if (EVP_MD_get_type((const EVP_MD )p2) != NID_sha1 && EVP_MD_get_type((const EVP_MD )p2) != NID_sha224 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256) {
152	0	ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
153	0	return 0;
154	0	}
155	0	dctx->pmd = p2;
156	0	return 1;
157
158	0	case EVP_PKEY_CTRL_MD:
159	0	if (EVP_MD_get_type((const EVP_MD )p2) != NID_sha1 && EVP_MD_get_type((const EVP_MD )p2) != NID_dsa && EVP_MD_get_type((const EVP_MD )p2) != NID_dsaWithSHA && EVP_MD_get_type((const EVP_MD )p2) != NID_sha224 && EVP_MD_get_type((const EVP_MD )p2) != NID_sha256 && EVP_MD_get_type((const EVP_MD )p2) != NID_sha384 && EVP_MD_get_type((const EVP_MD )p2) != NID_sha512 && EVP_MD_get_type((const EVP_MD )p2) != NID_sha3_224 && EVP_MD_get_type((const EVP_MD )p2) != NID_sha3_256 && EVP_MD_get_type((const EVP_MD )p2) != NID_sha3_384 && EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_512) {
160	0	ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
161	0	return 0;
162	0	}
163	0	dctx->md = p2;
164	0	return 1;
165
166	0	case EVP_PKEY_CTRL_GET_MD:
167	0	(const EVP_MD *)p2 = dctx->md;
168	0	return 1;
169
170	0	case EVP_PKEY_CTRL_DIGESTINIT:
171	0	case EVP_PKEY_CTRL_PKCS7_SIGN:
172	0	case EVP_PKEY_CTRL_CMS_SIGN:
173	0	return 1;
174
175	0	case EVP_PKEY_CTRL_PEER_KEY:
176	0	ERR_raise(ERR_LIB_DSA, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
177	0	return -2;
178	0	default:
179	0	return -2;
180	0	}
181	0	}
182
183		static int pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx,
184		const char type, const char value)
185	0	{
186	0	if (strcmp(type, "dsa_paramgen_bits") == 0) {
187	0	int nbits;
188	0	nbits = atoi(value);
189	0	return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits);
190	0	}
191	0	if (strcmp(type, "dsa_paramgen_q_bits") == 0) {
192	0	int qbits = atoi(value);
193	0	return EVP_PKEY_CTX_set_dsa_paramgen_q_bits(ctx, qbits);
194	0	}
195	0	if (strcmp(type, "dsa_paramgen_md") == 0) {
196	0	const EVP_MD *md = EVP_get_digestbyname(value);
197
198	0	if (md == NULL) {
199	0	ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
200	0	return 0;
201	0	}
202	0	return EVP_PKEY_CTX_set_dsa_paramgen_md(ctx, md);
203	0	}
204	0	return -2;
205	0	}
206
207		static int pkey_dsa_paramgen(EVP_PKEY_CTX ctx, EVP_PKEY pkey)
208	0	{
209	0	DSA *dsa = NULL;
210	0	DSA_PKEY_CTX *dctx = ctx->data;
211	0	BN_GENCB *pcb;
212	0	int ret, res;
213
214	0	if (ctx->pkey_gencb) {
215	0	pcb = BN_GENCB_new();
216	0	if (pcb == NULL)
217	0	return 0;
218	0	evp_pkey_set_cb_translate(pcb, ctx);
219	0	} else
220	0	pcb = NULL;
221	0	dsa = DSA_new();
222	0	if (dsa == NULL) {
223	0	BN_GENCB_free(pcb);
224	0	return 0;
225	0	}
226	0	if (dctx->md != NULL)
227	0	ossl_ffc_set_digest(&dsa->params, EVP_MD_get0_name(dctx->md), NULL);
228
229	0	ret = ossl_ffc_params_FIPS186_4_generate(NULL, &dsa->params,
230	0	FFC_PARAM_TYPE_DSA, dctx->nbits,
231	0	dctx->qbits, &res, pcb);
232	0	BN_GENCB_free(pcb);
233	0	if (ret > 0)
234	0	EVP_PKEY_assign_DSA(pkey, dsa);
235	0	else
236	0	DSA_free(dsa);
237	0	return ret;
238	0	}
239
240		static int pkey_dsa_keygen(EVP_PKEY_CTX ctx, EVP_PKEY pkey)
241	0	{
242	0	DSA *dsa = NULL;
243
244	0	if (ctx->pkey == NULL) {
245	0	ERR_raise(ERR_LIB_DSA, DSA_R_NO_PARAMETERS_SET);
246	0	return 0;
247	0	}
248	0	dsa = DSA_new();
249	0	if (dsa == NULL)
250	0	return 0;
251	0	EVP_PKEY_assign_DSA(pkey, dsa);
252		/* Note: if error return, pkey is freed by parent routine */
253	0	if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
254	0	return 0;
255	0	return DSA_generate_key((DSA *)EVP_PKEY_get0_DSA(pkey));
256	0	}
257
258		static const EVP_PKEY_METHOD dsa_pkey_meth = {
259		EVP_PKEY_DSA,
260		EVP_PKEY_FLAG_AUTOARGLEN,
261		pkey_dsa_init,
262		pkey_dsa_copy,
263		pkey_dsa_cleanup,
264
265		0,
266		pkey_dsa_paramgen,
267
268		0,
269		pkey_dsa_keygen,
270
271		0,
272		pkey_dsa_sign,
273
274		0,
275		pkey_dsa_verify,
276
277		0, 0,
278
279		0, 0, 0, 0,
280
281		0, 0,
282
283		0, 0,
284
285		0, 0,
286
287		pkey_dsa_ctrl,
288		pkey_dsa_ctrl_str
289		};
290
291		const EVP_PKEY_METHOD *ossl_dsa_pkey_method(void)
292	0	{
293	0	return &dsa_pkey_meth;
294	0	}