[thirdparty/openssl.git] / providers / implementations / signature / dsa.c

/*
 * Copyright 2019-2020 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 <string.h>

#include <openssl/crypto.h>
#include <openssl/core_dispatch.h>
#include <openssl/core_names.h>
#include <openssl/err.h>
#include <openssl/dsa.h>
#include <openssl/params.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include "internal/nelem.h"
#include "internal/sizes.h"
#include "internal/cryptlib.h"
#include "prov/providercommonerr.h"
#include "prov/implementations.h"
#include "prov/providercommonerr.h"
#include "prov/provider_ctx.h"
#include "crypto/dsa.h"
#include "prov/der_dsa.h"

static OSSL_FUNC_signature_newctx_fn dsa_newctx;
static OSSL_FUNC_signature_sign_init_fn dsa_signature_init;
static OSSL_FUNC_signature_verify_init_fn dsa_signature_init;
static OSSL_FUNC_signature_sign_fn dsa_sign;
static OSSL_FUNC_signature_verify_fn dsa_verify;
static OSSL_FUNC_signature_digest_sign_init_fn dsa_digest_signverify_init;
static OSSL_FUNC_signature_digest_sign_update_fn dsa_digest_signverify_update;
static OSSL_FUNC_signature_digest_sign_final_fn dsa_digest_sign_final;
static OSSL_FUNC_signature_digest_verify_init_fn dsa_digest_signverify_init;
static OSSL_FUNC_signature_digest_verify_update_fn dsa_digest_signverify_update;
static OSSL_FUNC_signature_digest_verify_final_fn dsa_digest_verify_final;
static OSSL_FUNC_signature_freectx_fn dsa_freectx;
static OSSL_FUNC_signature_dupctx_fn dsa_dupctx;
static OSSL_FUNC_signature_get_ctx_params_fn dsa_get_ctx_params;
static OSSL_FUNC_signature_gettable_ctx_params_fn dsa_gettable_ctx_params;
static OSSL_FUNC_signature_set_ctx_params_fn dsa_set_ctx_params;
static OSSL_FUNC_signature_settable_ctx_params_fn dsa_settable_ctx_params;
static OSSL_FUNC_signature_get_ctx_md_params_fn dsa_get_ctx_md_params;
static OSSL_FUNC_signature_gettable_ctx_md_params_fn dsa_gettable_ctx_md_params;
static OSSL_FUNC_signature_set_ctx_md_params_fn dsa_set_ctx_md_params;
static OSSL_FUNC_signature_settable_ctx_md_params_fn dsa_settable_ctx_md_params;

/*
 * What's passed as an actual key is defined by the KEYMGMT interface.
 * We happen to know that our KEYMGMT simply passes DSA structures, so
 * we use that here too.
 */

typedef struct {
    OPENSSL_CTX *libctx;
    char *propq;
    DSA *dsa;

    /*
     * Flag to determine if the hash function can be changed (1) or not (0)
     * Because it's dangerous to change during a DigestSign or DigestVerify
     * operation, this flag is cleared by their Init function, and set again
     * by their Final function.
     */
    unsigned int flag_allow_md : 1;

    char mdname[OSSL_MAX_NAME_SIZE];

    /* The Algorithm Identifier of the combined signature algorithm */
    unsigned char aid_buf[OSSL_MAX_ALGORITHM_ID_SIZE];
    unsigned char *aid;
    size_t  aid_len;

    /* main digest */
    EVP_MD *md;
    EVP_MD_CTX *mdctx;
    size_t mdsize;
} PROV_DSA_CTX;

static size_t dsa_get_md_size(const PROV_DSA_CTX *pdsactx)
{
    if (pdsactx->md != NULL)
        return EVP_MD_size(pdsactx->md);
    return 0;
}

static int dsa_get_md_nid(const EVP_MD *md)
{
    /*
     * Because the DSA library deals with NIDs, we need to translate.
     * We do so using EVP_MD_is_a(), and therefore need a name to NID
     * map.
     */
    static const OSSL_ITEM name_to_nid[] = {
        { NID_sha1,   OSSL_DIGEST_NAME_SHA1   },
        { NID_sha224, OSSL_DIGEST_NAME_SHA2_224 },
        { NID_sha256, OSSL_DIGEST_NAME_SHA2_256 },
        { NID_sha384, OSSL_DIGEST_NAME_SHA2_384 },
        { NID_sha512, OSSL_DIGEST_NAME_SHA2_512 },
        { NID_sha3_224, OSSL_DIGEST_NAME_SHA3_224 },
        { NID_sha3_256, OSSL_DIGEST_NAME_SHA3_256 },
        { NID_sha3_384, OSSL_DIGEST_NAME_SHA3_384 },
        { NID_sha3_512, OSSL_DIGEST_NAME_SHA3_512 },
    };
    size_t i;
    int mdnid = NID_undef;

    if (md == NULL)
        goto end;

    for (i = 0; i < OSSL_NELEM(name_to_nid); i++) {
        if (EVP_MD_is_a(md, name_to_nid[i].ptr)) {
            mdnid = (int)name_to_nid[i].id;
            break;
        }
    }

    if (mdnid == NID_undef)
        ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DIGEST);

 end:
    return mdnid;
}

static void *dsa_newctx(void *provctx, const char *propq)
{
    PROV_DSA_CTX *pdsactx = OPENSSL_zalloc(sizeof(PROV_DSA_CTX));

    if (pdsactx == NULL)
        return NULL;

    pdsactx->libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
    pdsactx->flag_allow_md = 1;
    if (propq != NULL && (pdsactx->propq = OPENSSL_strdup(propq)) == NULL) {
        OPENSSL_free(pdsactx);
        pdsactx = NULL;
        ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
    }
    return pdsactx;
}

static int dsa_setup_md(PROV_DSA_CTX *ctx,
                        const char *mdname, const char *mdprops)
{
    if (mdprops == NULL)
        mdprops = ctx->propq;

    if (mdname != NULL) {
        EVP_MD *md = EVP_MD_fetch(ctx->libctx, mdname, mdprops);
        int md_nid = dsa_get_md_nid(md);
        WPACKET pkt;

        if (md == NULL || md_nid == NID_undef) {
            EVP_MD_free(md);
            return 0;
        }

        EVP_MD_CTX_free(ctx->mdctx);
        EVP_MD_free(ctx->md);

        /*
         * TODO(3.0) Should we care about DER writing errors?
         * All it really means is that for some reason, there's no
         * AlgorithmIdentifier to be had, but the operation itself is
         * still valid, just as long as it's not used to construct
         * anything that needs an AlgorithmIdentifier.
         */
        ctx->aid_len = 0;
        if (WPACKET_init_der(&pkt, ctx->aid_buf, sizeof(ctx->aid_buf))
            && DER_w_algorithmIdentifier_DSA_with_MD(&pkt, -1, ctx->dsa,
                                                     md_nid)
            && WPACKET_finish(&pkt)) {
            WPACKET_get_total_written(&pkt, &ctx->aid_len);
            ctx->aid = WPACKET_get_curr(&pkt);
        }
        WPACKET_cleanup(&pkt);

        ctx->mdctx = NULL;
        ctx->md = md;
        OPENSSL_strlcpy(ctx->mdname, mdname, sizeof(ctx->mdname));
    }
    return 1;
}

static int dsa_signature_init(void *vpdsactx, void *vdsa)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;

    if (pdsactx == NULL || vdsa == NULL || !DSA_up_ref(vdsa))
        return 0;
    DSA_free(pdsactx->dsa);
    pdsactx->dsa = vdsa;
    return 1;
}

static int dsa_sign(void *vpdsactx, unsigned char *sig, size_t *siglen,
                    size_t sigsize, const unsigned char *tbs, size_t tbslen)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
    int ret;
    unsigned int sltmp;
    size_t dsasize = DSA_size(pdsactx->dsa);
    size_t mdsize = dsa_get_md_size(pdsactx);

    if (sig == NULL) {
        *siglen = dsasize;
        return 1;
    }

    if (sigsize < (size_t)dsasize)
        return 0;

    if (mdsize != 0 && tbslen != mdsize)
        return 0;

    ret = dsa_sign_int(0, tbs, tbslen, sig, &sltmp, pdsactx->dsa);
    if (ret <= 0)
        return 0;

    *siglen = sltmp;
    return 1;
}

static int dsa_verify(void *vpdsactx, const unsigned char *sig, size_t siglen,
                      const unsigned char *tbs, size_t tbslen)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
    size_t mdsize = dsa_get_md_size(pdsactx);

    if (mdsize != 0 && tbslen != mdsize)
        return 0;

    return DSA_verify(0, tbs, tbslen, sig, siglen, pdsactx->dsa);
}

static int dsa_digest_signverify_init(void *vpdsactx, const char *mdname,
                                      void *vdsa)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;

    pdsactx->flag_allow_md = 0;
    if (!dsa_signature_init(vpdsactx, vdsa))
        return 0;

    if (!dsa_setup_md(pdsactx, mdname, NULL))
        return 0;

    pdsactx->mdctx = EVP_MD_CTX_new();
    if (pdsactx->mdctx == NULL)
        goto error;

    if (!EVP_DigestInit_ex(pdsactx->mdctx, pdsactx->md, NULL))
        goto error;

    return 1;

 error:
    EVP_MD_CTX_free(pdsactx->mdctx);
    EVP_MD_free(pdsactx->md);
    pdsactx->mdctx = NULL;
    pdsactx->md = NULL;
    return 0;
}

int dsa_digest_signverify_update(void *vpdsactx, const unsigned char *data,
                                 size_t datalen)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;

    if (pdsactx == NULL || pdsactx->mdctx == NULL)
        return 0;

    return EVP_DigestUpdate(pdsactx->mdctx, data, datalen);
}

int dsa_digest_sign_final(void *vpdsactx, unsigned char *sig, size_t *siglen,
                          size_t sigsize)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
    unsigned char digest[EVP_MAX_MD_SIZE];
    unsigned int dlen = 0;

    if (pdsactx == NULL || pdsactx->mdctx == NULL)
        return 0;

    /*
     * If sig is NULL then we're just finding out the sig size. Other fields
     * are ignored. Defer to dsa_sign.
     */
    if (sig != NULL) {
        /*
         * TODO(3.0): There is the possibility that some externally provided
         * digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
         * but that problem is much larger than just in DSA.
         */
        if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
            return 0;
    }

    pdsactx->flag_allow_md = 1;

    return dsa_sign(vpdsactx, sig, siglen, sigsize, digest, (size_t)dlen);
}


int dsa_digest_verify_final(void *vpdsactx, const unsigned char *sig,
                            size_t siglen)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
    unsigned char digest[EVP_MAX_MD_SIZE];
    unsigned int dlen = 0;

    if (pdsactx == NULL || pdsactx->mdctx == NULL)
        return 0;

    /*
     * TODO(3.0): There is the possibility that some externally provided
     * digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
     * but that problem is much larger than just in DSA.
     */
    if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
        return 0;

    pdsactx->flag_allow_md = 1;

    return dsa_verify(vpdsactx, sig, siglen, digest, (size_t)dlen);
}

static void dsa_freectx(void *vpdsactx)
{
    PROV_DSA_CTX *ctx = (PROV_DSA_CTX *)vpdsactx;

    OPENSSL_free(ctx->propq);
    EVP_MD_CTX_free(ctx->mdctx);
    EVP_MD_free(ctx->md);
    ctx->propq = NULL;
    ctx->mdctx = NULL;
    ctx->md = NULL;
    ctx->mdsize = 0;
    DSA_free(ctx->dsa);
    OPENSSL_free(ctx);
}

static void *dsa_dupctx(void *vpdsactx)
{
    PROV_DSA_CTX *srcctx = (PROV_DSA_CTX *)vpdsactx;
    PROV_DSA_CTX *dstctx;

    dstctx = OPENSSL_zalloc(sizeof(*srcctx));
    if (dstctx == NULL)
        return NULL;

    *dstctx = *srcctx;
    dstctx->dsa = NULL;
    dstctx->md = NULL;
    dstctx->mdctx = NULL;

    if (srcctx->dsa != NULL && !DSA_up_ref(srcctx->dsa))
        goto err;
    dstctx->dsa = srcctx->dsa;

    if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
        goto err;
    dstctx->md = srcctx->md;

    if (srcctx->mdctx != NULL) {
        dstctx->mdctx = EVP_MD_CTX_new();
        if (dstctx->mdctx == NULL
                || !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
            goto err;
    }

    return dstctx;
 err:
    dsa_freectx(dstctx);
    return NULL;
}

static int dsa_get_ctx_params(void *vpdsactx, OSSL_PARAM *params)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
    OSSL_PARAM *p;

    if (pdsactx == NULL || params == NULL)
        return 0;

    p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
    if (p != NULL
        && !OSSL_PARAM_set_octet_string(p, pdsactx->aid, pdsactx->aid_len))
        return 0;

    p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
    if (p != NULL && !OSSL_PARAM_set_utf8_string(p, pdsactx->mdname))
        return 0;

    return 1;
}

static const OSSL_PARAM known_gettable_ctx_params[] = {
    OSSL_PARAM_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID, NULL, 0),
    OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
    OSSL_PARAM_END
};

static const OSSL_PARAM *dsa_gettable_ctx_params(void)
{
    return known_gettable_ctx_params;
}

static int dsa_set_ctx_params(void *vpdsactx, const OSSL_PARAM params[])
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
    const OSSL_PARAM *p;

    if (pdsactx == NULL || params == NULL)
        return 0;

    p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
    /* Not allowed during certain operations */
    if (p != NULL && !pdsactx->flag_allow_md)
        return 0;
    if (p != NULL) {
        char mdname[OSSL_MAX_NAME_SIZE] = "", *pmdname = mdname;
        char mdprops[OSSL_MAX_PROPQUERY_SIZE] = "", *pmdprops = mdprops;
        const OSSL_PARAM *propsp =
            OSSL_PARAM_locate_const(params,
                                    OSSL_SIGNATURE_PARAM_PROPERTIES);

        if (!OSSL_PARAM_get_utf8_string(p, &pmdname, sizeof(mdname)))
            return 0;
        if (propsp != NULL
            && !OSSL_PARAM_get_utf8_string(propsp, &pmdprops, sizeof(mdprops)))
            return 0;
        if (!dsa_setup_md(pdsactx, mdname, mdprops))
            return 0;
    }

    return 1;
}

static const OSSL_PARAM known_settable_ctx_params[] = {
    OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
    OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PROPERTIES, NULL, 0),
    OSSL_PARAM_END
};

static const OSSL_PARAM *dsa_settable_ctx_params(void)
{
    /*
     * TODO(3.0): Should this function return a different set of settable ctx
     * params if the ctx is being used for a DigestSign/DigestVerify? In that
     * case it is not allowed to set the digest size/digest name because the
     * digest is explicitly set as part of the init.
     */
    return known_settable_ctx_params;
}

static int dsa_get_ctx_md_params(void *vpdsactx, OSSL_PARAM *params)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;

    if (pdsactx->mdctx == NULL)
        return 0;

    return EVP_MD_CTX_get_params(pdsactx->mdctx, params);
}

static const OSSL_PARAM *dsa_gettable_ctx_md_params(void *vpdsactx)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;

    if (pdsactx->md == NULL)
        return 0;

    return EVP_MD_gettable_ctx_params(pdsactx->md);
}

static int dsa_set_ctx_md_params(void *vpdsactx, const OSSL_PARAM params[])
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;

    if (pdsactx->mdctx == NULL)
        return 0;

    return EVP_MD_CTX_set_params(pdsactx->mdctx, params);
}

static const OSSL_PARAM *dsa_settable_ctx_md_params(void *vpdsactx)
{
    PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;

    if (pdsactx->md == NULL)
        return 0;

    return EVP_MD_settable_ctx_params(pdsactx->md);
}

const OSSL_DISPATCH dsa_signature_functions[] = {
    { OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))dsa_newctx },
    { OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))dsa_signature_init },
    { OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))dsa_sign },
    { OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))dsa_signature_init },
    { OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))dsa_verify },
    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
      (void (*)(void))dsa_digest_signverify_init },
    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
      (void (*)(void))dsa_digest_signverify_update },
    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
      (void (*)(void))dsa_digest_sign_final },
    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
      (void (*)(void))dsa_digest_signverify_init },
    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
      (void (*)(void))dsa_digest_signverify_update },
    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
      (void (*)(void))dsa_digest_verify_final },
    { OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))dsa_freectx },
    { OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))dsa_dupctx },
    { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))dsa_get_ctx_params },
    { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
      (void (*)(void))dsa_gettable_ctx_params },
    { OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))dsa_set_ctx_params },
    { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
      (void (*)(void))dsa_settable_ctx_params },
    { OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
      (void (*)(void))dsa_get_ctx_md_params },
    { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
      (void (*)(void))dsa_gettable_ctx_md_params },
    { OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
      (void (*)(void))dsa_set_ctx_md_params },
    { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
      (void (*)(void))dsa_settable_ctx_md_params },
    { 0, NULL }
};
Commit	Line	Data
4889dadc	1	/*
33388b44	2	* Copyright 2019-2020 The OpenSSL Project Authors. All Rights Reserved.
4889dadc MC	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
f41ac0ee P	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
505b41fc RL	16	#include <string.h>
505b41fc RL	17
4889dadc	18	#include <openssl/crypto.h>
23c48d94	19	#include <openssl/core_dispatch.h>
4889dadc	20	#include <openssl/core_names.h>
505b41fc	21	#include <openssl/err.h>
4889dadc MC	22	#include <openssl/dsa.h>
4889dadc MC	23	#include <openssl/params.h>
45a845e4	24	#include <openssl/evp.h>
8bee6512	25	#include <openssl/err.h>
505b41fc	26	#include "internal/nelem.h"
c24937d5	27	#include "internal/sizes.h"
8c555803	28	#include "internal/cryptlib.h"
505b41fc	29	#include "prov/providercommonerr.h"
af3e7e1b	30	#include "prov/implementations.h"
8bee6512	31	#include "prov/providercommonerr.h"
ddd21319	32	#include "prov/provider_ctx.h"
e683582b	33	#include "crypto/dsa.h"
8c555803	34	#include "prov/der_dsa.h"
4889dadc	35
363b1e5d DMSP	36	static OSSL_FUNC_signature_newctx_fn dsa_newctx;
	37	static OSSL_FUNC_signature_sign_init_fn dsa_signature_init;
	38	static OSSL_FUNC_signature_verify_init_fn dsa_signature_init;
	39	static OSSL_FUNC_signature_sign_fn dsa_sign;
	40	static OSSL_FUNC_signature_verify_fn dsa_verify;
	41	static OSSL_FUNC_signature_digest_sign_init_fn dsa_digest_signverify_init;
	42	static OSSL_FUNC_signature_digest_sign_update_fn dsa_digest_signverify_update;
	43	static OSSL_FUNC_signature_digest_sign_final_fn dsa_digest_sign_final;
	44	static OSSL_FUNC_signature_digest_verify_init_fn dsa_digest_signverify_init;
	45	static OSSL_FUNC_signature_digest_verify_update_fn dsa_digest_signverify_update;
	46	static OSSL_FUNC_signature_digest_verify_final_fn dsa_digest_verify_final;
	47	static OSSL_FUNC_signature_freectx_fn dsa_freectx;
	48	static OSSL_FUNC_signature_dupctx_fn dsa_dupctx;
	49	static OSSL_FUNC_signature_get_ctx_params_fn dsa_get_ctx_params;
	50	static OSSL_FUNC_signature_gettable_ctx_params_fn dsa_gettable_ctx_params;
	51	static OSSL_FUNC_signature_set_ctx_params_fn dsa_set_ctx_params;
	52	static OSSL_FUNC_signature_settable_ctx_params_fn dsa_settable_ctx_params;
	53	static OSSL_FUNC_signature_get_ctx_md_params_fn dsa_get_ctx_md_params;
	54	static OSSL_FUNC_signature_gettable_ctx_md_params_fn dsa_gettable_ctx_md_params;
	55	static OSSL_FUNC_signature_set_ctx_md_params_fn dsa_set_ctx_md_params;
	56	static OSSL_FUNC_signature_settable_ctx_md_params_fn dsa_settable_ctx_md_params;
4889dadc MC	57
	58	/*
	59	* What's passed as an actual key is defined by the KEYMGMT interface.
	60	* We happen to know that our KEYMGMT simply passes DSA structures, so
	61	* we use that here too.
	62	*/
	63
	64	typedef struct {
45a845e4	65	OPENSSL_CTX *libctx;
2c6094ba	66	char *propq;
4889dadc	67	DSA *dsa;
8bee6512 RL	68
	69	/*
	70	* Flag to determine if the hash function can be changed (1) or not (0)
	71	* Because it's dangerous to change during a DigestSign or DigestVerify
	72	* operation, this flag is cleared by their Init function, and set again
	73	* by their Final function.
	74	*/
	75	unsigned int flag_allow_md : 1;
	76
c24937d5	77	char mdname[OSSL_MAX_NAME_SIZE];
505b41fc	78
edd3b7a3	79	/* The Algorithm Identifier of the combined signature algorithm */
8c555803 RL	80	unsigned char aid_buf[OSSL_MAX_ALGORITHM_ID_SIZE];
8c555803 RL	81	unsigned char *aid;
505b41fc RL	82	size_t aid_len;
	83
	84	/* main digest */
45a845e4 MC	85	EVP_MD *md;
45a845e4 MC	86	EVP_MD_CTX *mdctx;
8bee6512	87	size_t mdsize;
4889dadc MC	88	} PROV_DSA_CTX;
4889dadc MC	89
8bee6512 RL	90	static size_t dsa_get_md_size(const PROV_DSA_CTX *pdsactx)
	91	{
	92	if (pdsactx->md != NULL)
	93	return EVP_MD_size(pdsactx->md);
	94	return 0;
	95	}
	96
	97	static int dsa_get_md_nid(const EVP_MD *md)
	98	{
	99	/*
	100	* Because the DSA library deals with NIDs, we need to translate.
	101	* We do so using EVP_MD_is_a(), and therefore need a name to NID
	102	* map.
	103	*/
	104	static const OSSL_ITEM name_to_nid[] = {
	105	{ NID_sha1, OSSL_DIGEST_NAME_SHA1 },
	106	{ NID_sha224, OSSL_DIGEST_NAME_SHA2_224 },
	107	{ NID_sha256, OSSL_DIGEST_NAME_SHA2_256 },
	108	{ NID_sha384, OSSL_DIGEST_NAME_SHA2_384 },
	109	{ NID_sha512, OSSL_DIGEST_NAME_SHA2_512 },
	110	{ NID_sha3_224, OSSL_DIGEST_NAME_SHA3_224 },
	111	{ NID_sha3_256, OSSL_DIGEST_NAME_SHA3_256 },
	112	{ NID_sha3_384, OSSL_DIGEST_NAME_SHA3_384 },
	113	{ NID_sha3_512, OSSL_DIGEST_NAME_SHA3_512 },
	114	};
	115	size_t i;
	116	int mdnid = NID_undef;
	117
	118	if (md == NULL)
	119	goto end;
	120
	121	for (i = 0; i < OSSL_NELEM(name_to_nid); i++) {
	122	if (EVP_MD_is_a(md, name_to_nid[i].ptr)) {
	123	mdnid = (int)name_to_nid[i].id;
	124	break;
	125	}
	126	}
	127
	128	if (mdnid == NID_undef)
	129	ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DIGEST);
	130
	131	end:
	132	return mdnid;
	133	}
	134
2c6094ba	135	static void dsa_newctx(void provctx, const char *propq)
4889dadc	136	{
45a845e4 MC	137	PROV_DSA_CTX *pdsactx = OPENSSL_zalloc(sizeof(PROV_DSA_CTX));
	138
	139	if (pdsactx == NULL)
	140	return NULL;
	141
	142	pdsactx->libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
8bee6512	143	pdsactx->flag_allow_md = 1;
2c6094ba RL	144	if (propq != NULL && (pdsactx->propq = OPENSSL_strdup(propq)) == NULL) {
	145	OPENSSL_free(pdsactx);
	146	pdsactx = NULL;
	147	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
	148	}
45a845e4	149	return pdsactx;
4889dadc MC	150	}
4889dadc MC	151
8bee6512 RL	152	static int dsa_setup_md(PROV_DSA_CTX *ctx,
	153	const char mdname, const char mdprops)
	154	{
2c6094ba RL	155	if (mdprops == NULL)
	156	mdprops = ctx->propq;
	157
8bee6512 RL	158	if (mdname != NULL) {
	159	EVP_MD *md = EVP_MD_fetch(ctx->libctx, mdname, mdprops);
	160	int md_nid = dsa_get_md_nid(md);
8c555803	161	WPACKET pkt;
8bee6512	162
8c555803	163	if (md == NULL \|\| md_nid == NID_undef) {
8bee6512 RL	164	EVP_MD_free(md);
	165	return 0;
	166	}
	167
8c555803 RL	168	EVP_MD_CTX_free(ctx->mdctx);
	169	EVP_MD_free(ctx->md);
	170
	171	/*
	172	* TODO(3.0) Should we care about DER writing errors?
	173	* All it really means is that for some reason, there's no
	174	* AlgorithmIdentifier to be had, but the operation itself is
	175	* still valid, just as long as it's not used to construct
	176	* anything that needs an AlgorithmIdentifier.
	177	*/
	178	ctx->aid_len = 0;
	179	if (WPACKET_init_der(&pkt, ctx->aid_buf, sizeof(ctx->aid_buf))
a30027b6 RL	180	&& DER_w_algorithmIdentifier_DSA_with_MD(&pkt, -1, ctx->dsa,
a30027b6 RL	181	md_nid)
8c555803 RL	182	&& WPACKET_finish(&pkt)) {
	183	WPACKET_get_total_written(&pkt, &ctx->aid_len);
	184	ctx->aid = WPACKET_get_curr(&pkt);
	185	}
	186	WPACKET_cleanup(&pkt);
	187
	188	ctx->mdctx = NULL;
8bee6512 RL	189	ctx->md = md;
	190	OPENSSL_strlcpy(ctx->mdname, mdname, sizeof(ctx->mdname));
	191	}
	192	return 1;
	193	}
	194
390acbeb	195	static int dsa_signature_init(void vpdsactx, void vdsa)
4889dadc MC	196	{
	197	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	198
	199	if (pdsactx == NULL \|\| vdsa == NULL \|\| !DSA_up_ref(vdsa))
	200	return 0;
	201	DSA_free(pdsactx->dsa);
	202	pdsactx->dsa = vdsa;
	203	return 1;
	204	}
	205
	206	static int dsa_sign(void vpdsactx, unsigned char sig, size_t *siglen,
	207	size_t sigsize, const unsigned char *tbs, size_t tbslen)
	208	{
	209	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	210	int ret;
	211	unsigned int sltmp;
	212	size_t dsasize = DSA_size(pdsactx->dsa);
8bee6512	213	size_t mdsize = dsa_get_md_size(pdsactx);
4889dadc MC	214
	215	if (sig == NULL) {
	216	*siglen = dsasize;
	217	return 1;
	218	}
	219
	220	if (sigsize < (size_t)dsasize)
	221	return 0;
	222
8bee6512	223	if (mdsize != 0 && tbslen != mdsize)
4889dadc MC	224	return 0;
4889dadc MC	225
8083fd3a	226	ret = dsa_sign_int(0, tbs, tbslen, sig, &sltmp, pdsactx->dsa);
4889dadc MC	227	if (ret <= 0)
	228	return 0;
	229
	230	*siglen = sltmp;
	231	return 1;
	232	}
	233
390acbeb MC	234	static int dsa_verify(void vpdsactx, const unsigned char sig, size_t siglen,
	235	const unsigned char *tbs, size_t tbslen)
	236	{
	237	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
8bee6512	238	size_t mdsize = dsa_get_md_size(pdsactx);
390acbeb	239
8bee6512	240	if (mdsize != 0 && tbslen != mdsize)
390acbeb MC	241	return 0;
	242
	243	return DSA_verify(0, tbs, tbslen, sig, siglen, pdsactx->dsa);
	244	}
	245
45a845e4	246	static int dsa_digest_signverify_init(void vpdsactx, const char mdname,
2c6094ba	247	void *vdsa)
45a845e4 MC	248	{
45a845e4 MC	249	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
45a845e4	250
8bee6512	251	pdsactx->flag_allow_md = 0;
45a845e4 MC	252	if (!dsa_signature_init(vpdsactx, vdsa))
	253	return 0;
	254
2c6094ba	255	if (!dsa_setup_md(pdsactx, mdname, NULL))
8bee6512	256	return 0;
505b41fc	257
45a845e4 MC	258	pdsactx->mdctx = EVP_MD_CTX_new();
45a845e4 MC	259	if (pdsactx->mdctx == NULL)
505b41fc	260	goto error;
45a845e4	261
505b41fc RL	262	if (!EVP_DigestInit_ex(pdsactx->mdctx, pdsactx->md, NULL))
505b41fc RL	263	goto error;
45a845e4 MC	264
45a845e4 MC	265	return 1;
505b41fc RL	266
	267	error:
	268	EVP_MD_CTX_free(pdsactx->mdctx);
	269	EVP_MD_free(pdsactx->md);
	270	pdsactx->mdctx = NULL;
505b41fc RL	271	pdsactx->md = NULL;
505b41fc RL	272	return 0;
45a845e4 MC	273	}
	274
	275	int dsa_digest_signverify_update(void vpdsactx, const unsigned char data,
	276	size_t datalen)
	277	{
	278	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	279
	280	if (pdsactx == NULL \|\| pdsactx->mdctx == NULL)
	281	return 0;
	282
	283	return EVP_DigestUpdate(pdsactx->mdctx, data, datalen);
	284	}
	285
	286	int dsa_digest_sign_final(void vpdsactx, unsigned char sig, size_t *siglen,
	287	size_t sigsize)
	288	{
	289	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	290	unsigned char digest[EVP_MAX_MD_SIZE];
	291	unsigned int dlen = 0;
	292
	293	if (pdsactx == NULL \|\| pdsactx->mdctx == NULL)
	294	return 0;
	295
	296	/*
	297	* If sig is NULL then we're just finding out the sig size. Other fields
	298	* are ignored. Defer to dsa_sign.
	299	*/
	300	if (sig != NULL) {
	301	/*
	302	* TODO(3.0): There is the possibility that some externally provided
	303	* digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
	304	* but that problem is much larger than just in DSA.
	305	*/
	306	if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
	307	return 0;
	308	}
	309
8bee6512 RL	310	pdsactx->flag_allow_md = 1;
8bee6512 RL	311
45a845e4 MC	312	return dsa_sign(vpdsactx, sig, siglen, sigsize, digest, (size_t)dlen);
	313	}
	314
	315
	316	int dsa_digest_verify_final(void vpdsactx, const unsigned char sig,
	317	size_t siglen)
	318	{
	319	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	320	unsigned char digest[EVP_MAX_MD_SIZE];
	321	unsigned int dlen = 0;
	322
	323	if (pdsactx == NULL \|\| pdsactx->mdctx == NULL)
	324	return 0;
	325
	326	/*
	327	* TODO(3.0): There is the possibility that some externally provided
	328	* digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
	329	* but that problem is much larger than just in DSA.
	330	*/
	331	if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
	332	return 0;
	333
8bee6512 RL	334	pdsactx->flag_allow_md = 1;
8bee6512 RL	335
45a845e4 MC	336	return dsa_verify(vpdsactx, sig, siglen, digest, (size_t)dlen);
45a845e4 MC	337	}
390acbeb	338
4889dadc MC	339	static void dsa_freectx(void *vpdsactx)
4889dadc MC	340	{
4f2271d5 SL	341	PROV_DSA_CTX ctx = (PROV_DSA_CTX )vpdsactx;
	342
	343	OPENSSL_free(ctx->propq);
	344	EVP_MD_CTX_free(ctx->mdctx);
	345	EVP_MD_free(ctx->md);
	346	ctx->propq = NULL;
	347	ctx->mdctx = NULL;
	348	ctx->md = NULL;
	349	ctx->mdsize = 0;
	350	DSA_free(ctx->dsa);
	351	OPENSSL_free(ctx);
4889dadc MC	352	}
	353
	354	static void dsa_dupctx(void vpdsactx)
	355	{
	356	PROV_DSA_CTX srcctx = (PROV_DSA_CTX )vpdsactx;
	357	PROV_DSA_CTX *dstctx;
	358
	359	dstctx = OPENSSL_zalloc(sizeof(*srcctx));
	360	if (dstctx == NULL)
	361	return NULL;
	362
	363	dstctx = srcctx;
45a845e4 MC	364	dstctx->dsa = NULL;
	365	dstctx->md = NULL;
	366	dstctx->mdctx = NULL;
	367
	368	if (srcctx->dsa != NULL && !DSA_up_ref(srcctx->dsa))
	369	goto err;
	370	dstctx->dsa = srcctx->dsa;
	371
	372	if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
	373	goto err;
	374	dstctx->md = srcctx->md;
	375
	376	if (srcctx->mdctx != NULL) {
	377	dstctx->mdctx = EVP_MD_CTX_new();
	378	if (dstctx->mdctx == NULL
	379	\|\| !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
	380	goto err;
4889dadc MC	381	}
	382
	383	return dstctx;
45a845e4 MC	384	err:
	385	dsa_freectx(dstctx);
	386	return NULL;
4889dadc MC	387	}
4889dadc MC	388
9c45222d MC	389	static int dsa_get_ctx_params(void vpdsactx, OSSL_PARAM params)
	390	{
	391	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	392	OSSL_PARAM *p;
	393
	394	if (pdsactx == NULL \|\| params == NULL)
	395	return 0;
	396
505b41fc RL	397	p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
	398	if (p != NULL
	399	&& !OSSL_PARAM_set_octet_string(p, pdsactx->aid, pdsactx->aid_len))
	400	return 0;
	401
9c45222d	402	p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
8bee6512	403	if (p != NULL && !OSSL_PARAM_set_utf8_string(p, pdsactx->mdname))
9c45222d MC	404	return 0;
	405
	406	return 1;
	407	}
	408
	409	static const OSSL_PARAM known_gettable_ctx_params[] = {
505b41fc	410	OSSL_PARAM_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID, NULL, 0),
9c45222d MC	411	OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
	412	OSSL_PARAM_END
	413	};
	414
	415	static const OSSL_PARAM *dsa_gettable_ctx_params(void)
	416	{
	417	return known_gettable_ctx_params;
	418	}
	419
	420	static int dsa_set_ctx_params(void *vpdsactx, const OSSL_PARAM params[])
4889dadc MC	421	{
	422	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	423	const OSSL_PARAM *p;
4889dadc MC	424
	425	if (pdsactx == NULL \|\| params == NULL)
	426	return 0;
	427
9c45222d	428	p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
8bee6512 RL	429	/* Not allowed during certain operations */
8bee6512 RL	430	if (p != NULL && !pdsactx->flag_allow_md)
9c45222d	431	return 0;
8bee6512 RL	432	if (p != NULL) {
	433	char mdname[OSSL_MAX_NAME_SIZE] = "", *pmdname = mdname;
	434	char mdprops[OSSL_MAX_PROPQUERY_SIZE] = "", *pmdprops = mdprops;
	435	const OSSL_PARAM *propsp =
	436	OSSL_PARAM_locate_const(params,
	437	OSSL_SIGNATURE_PARAM_PROPERTIES);
	438
	439	if (!OSSL_PARAM_get_utf8_string(p, &pmdname, sizeof(mdname)))
	440	return 0;
	441	if (propsp != NULL
	442	&& !OSSL_PARAM_get_utf8_string(propsp, &pmdprops, sizeof(mdprops)))
	443	return 0;
	444	if (!dsa_setup_md(pdsactx, mdname, mdprops))
	445	return 0;
	446	}
4889dadc MC	447
	448	return 1;
	449	}
	450
9c45222d	451	static const OSSL_PARAM known_settable_ctx_params[] = {
9c45222d	452	OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
b8086652	453	OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PROPERTIES, NULL, 0),
9c45222d MC	454	OSSL_PARAM_END
	455	};
	456
	457	static const OSSL_PARAM *dsa_settable_ctx_params(void)
	458	{
45a845e4 MC	459	/*
	460	* TODO(3.0): Should this function return a different set of settable ctx
	461	* params if the ctx is being used for a DigestSign/DigestVerify? In that
	462	* case it is not allowed to set the digest size/digest name because the
	463	* digest is explicitly set as part of the init.
	464	*/
9c45222d MC	465	return known_settable_ctx_params;
	466	}
	467
45a845e4 MC	468	static int dsa_get_ctx_md_params(void vpdsactx, OSSL_PARAM params)
	469	{
	470	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	471
	472	if (pdsactx->mdctx == NULL)
	473	return 0;
	474
	475	return EVP_MD_CTX_get_params(pdsactx->mdctx, params);
	476	}
	477
	478	static const OSSL_PARAM dsa_gettable_ctx_md_params(void vpdsactx)
	479	{
	480	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	481
	482	if (pdsactx->md == NULL)
	483	return 0;
	484
	485	return EVP_MD_gettable_ctx_params(pdsactx->md);
	486	}
	487
	488	static int dsa_set_ctx_md_params(void *vpdsactx, const OSSL_PARAM params[])
	489	{
	490	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	491
	492	if (pdsactx->mdctx == NULL)
	493	return 0;
	494
	495	return EVP_MD_CTX_set_params(pdsactx->mdctx, params);
	496	}
	497
	498	static const OSSL_PARAM dsa_settable_ctx_md_params(void vpdsactx)
	499	{
	500	PROV_DSA_CTX pdsactx = (PROV_DSA_CTX )vpdsactx;
	501
	502	if (pdsactx->md == NULL)
	503	return 0;
	504
	505	return EVP_MD_settable_ctx_params(pdsactx->md);
	506	}
	507
4889dadc MC	508	const OSSL_DISPATCH dsa_signature_functions[] = {
4889dadc MC	509	{ OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))dsa_newctx },
390acbeb	510	{ OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))dsa_signature_init },
4889dadc	511	{ OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))dsa_sign },
390acbeb MC	512	{ OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))dsa_signature_init },
390acbeb MC	513	{ OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))dsa_verify },
45a845e4 MC	514	{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
	515	(void (*)(void))dsa_digest_signverify_init },
	516	{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
	517	(void (*)(void))dsa_digest_signverify_update },
	518	{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
	519	(void (*)(void))dsa_digest_sign_final },
	520	{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
	521	(void (*)(void))dsa_digest_signverify_init },
	522	{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
	523	(void (*)(void))dsa_digest_signverify_update },
	524	{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
	525	(void (*)(void))dsa_digest_verify_final },
4889dadc MC	526	{ OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))dsa_freectx },
4889dadc MC	527	{ OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))dsa_dupctx },
9c45222d MC	528	{ OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))dsa_get_ctx_params },
	529	{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
	530	(void (*)(void))dsa_gettable_ctx_params },
	531	{ OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))dsa_set_ctx_params },
	532	{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
	533	(void (*)(void))dsa_settable_ctx_params },
45a845e4 MC	534	{ OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
	535	(void (*)(void))dsa_get_ctx_md_params },
	536	{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
	537	(void (*)(void))dsa_gettable_ctx_md_params },
	538	{ OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
	539	(void (*)(void))dsa_set_ctx_md_params },
	540	{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
	541	(void (*)(void))dsa_settable_ctx_md_params },
4889dadc MC	542	{ 0, NULL }
4889dadc MC	543	};