/src/openssl31/providers/implementations/signature/sm2_sig.c

Source (jump to first uncovered line)
/*
 * Copyright 2020-2022 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
 */

/*
 * ECDSA low level APIs are deprecated for public use, but still ok for
 * internal use - SM2 implementation uses ECDSA_size() function.
 */
#include "internal/deprecated.h"

#include <string.h> /* memcpy */
#include <openssl/crypto.h>
#include <openssl/core_dispatch.h>
#include <openssl/core_names.h>
#include <openssl/dsa.h>
#include <openssl/params.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/proverr.h>
#include "internal/nelem.h"
#include "internal/sizes.h"
#include "internal/cryptlib.h"
#include "internal/sm3.h"
#include "prov/implementations.h"
#include "prov/providercommon.h"
#include "prov/provider_ctx.h"
#include "crypto/ec.h"
#include "crypto/sm2.h"
#include "prov/der_sm2.h"

static OSSL_FUNC_signature_newctx_fn sm2sig_newctx;
static OSSL_FUNC_signature_sign_init_fn sm2sig_signature_init;
static OSSL_FUNC_signature_verify_init_fn sm2sig_signature_init;
static OSSL_FUNC_signature_sign_fn sm2sig_sign;
static OSSL_FUNC_signature_verify_fn sm2sig_verify;
static OSSL_FUNC_signature_digest_sign_init_fn sm2sig_digest_signverify_init;
static OSSL_FUNC_signature_digest_sign_update_fn sm2sig_digest_signverify_update;
static OSSL_FUNC_signature_digest_sign_final_fn sm2sig_digest_sign_final;
static OSSL_FUNC_signature_digest_verify_init_fn sm2sig_digest_signverify_init;
static OSSL_FUNC_signature_digest_verify_update_fn sm2sig_digest_signverify_update;
static OSSL_FUNC_signature_digest_verify_final_fn sm2sig_digest_verify_final;
static OSSL_FUNC_signature_freectx_fn sm2sig_freectx;
static OSSL_FUNC_signature_dupctx_fn sm2sig_dupctx;
static OSSL_FUNC_signature_get_ctx_params_fn sm2sig_get_ctx_params;
static OSSL_FUNC_signature_gettable_ctx_params_fn sm2sig_gettable_ctx_params;
static OSSL_FUNC_signature_set_ctx_params_fn sm2sig_set_ctx_params;
static OSSL_FUNC_signature_settable_ctx_params_fn sm2sig_settable_ctx_params;
static OSSL_FUNC_signature_get_ctx_md_params_fn sm2sig_get_ctx_md_params;
static OSSL_FUNC_signature_gettable_ctx_md_params_fn sm2sig_gettable_ctx_md_params;
static OSSL_FUNC_signature_set_ctx_md_params_fn sm2sig_set_ctx_md_params;
static OSSL_FUNC_signature_settable_ctx_md_params_fn sm2sig_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 EC structures, so
 * we use that here too.
 */
typedef struct {
    OSSL_LIB_CTX *libctx;
    char *propq;
    EC_KEY *ec;

    /*
     * Flag to determine if the 'z' digest needs to be computed and fed to the
     * hash function.
     * This flag should be set on initialization and the computation should
     * be performed only once, on first update.
     */
    unsigned int flag_compute_z_digest : 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;

    /* SM2 ID used for calculating the Z value */
    unsigned char *id;
    size_t id_len;
} PROV_SM2_CTX;

static int sm2sig_set_mdname(PROV_SM2_CTX *psm2ctx, const char *mdname)
{
    if (psm2ctx->md == NULL) /* We need an SM3 md to compare with */
        psm2ctx->md = EVP_MD_fetch(psm2ctx->libctx, psm2ctx->mdname,
                                   psm2ctx->propq);
    if (psm2ctx->md == NULL)
        return 0;

    if (mdname == NULL)
        return 1;

    if (strlen(mdname) >= sizeof(psm2ctx->mdname)
        || !EVP_MD_is_a(psm2ctx->md, mdname)) {
        ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST, "digest=%s",
                       mdname);
        return 0;
    }

    OPENSSL_strlcpy(psm2ctx->mdname, mdname, sizeof(psm2ctx->mdname));
    return 1;
}

static void *sm2sig_newctx(void *provctx, const char *propq)
{
    PROV_SM2_CTX *ctx = OPENSSL_zalloc(sizeof(PROV_SM2_CTX));

    if (ctx == NULL)
        return NULL;

    ctx->libctx = PROV_LIBCTX_OF(provctx);
    if (propq != NULL && (ctx->propq = OPENSSL_strdup(propq)) == NULL) {
        OPENSSL_free(ctx);
        ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
        return NULL;
    }
    ctx->mdsize = SM3_DIGEST_LENGTH;
    strcpy(ctx->mdname, OSSL_DIGEST_NAME_SM3);
    return ctx;
}

static int sm2sig_signature_init(void *vpsm2ctx, void *ec,
                                 const OSSL_PARAM params[])
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;

    if (!ossl_prov_is_running()
            || psm2ctx == NULL)
        return 0;

    if (ec == NULL && psm2ctx->ec == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
        return 0;
    }

    if (ec != NULL) {
        if (!EC_KEY_up_ref(ec))
            return 0;
        EC_KEY_free(psm2ctx->ec);
        psm2ctx->ec = ec;
    }

    return sm2sig_set_ctx_params(psm2ctx, params);
}

static int sm2sig_sign(void *vpsm2ctx, unsigned char *sig, size_t *siglen,
                       size_t sigsize, const unsigned char *tbs, size_t tbslen)
{
    PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;
    int ret;
    unsigned int sltmp;
    /* SM2 uses ECDSA_size as well */
    size_t ecsize = ECDSA_size(ctx->ec);

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

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

    if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
        return 0;

    ret = ossl_sm2_internal_sign(tbs, tbslen, sig, &sltmp, ctx->ec);
    if (ret <= 0)
        return 0;

    *siglen = sltmp;
    return 1;
}

static int sm2sig_verify(void *vpsm2ctx, const unsigned char *sig, size_t siglen,
                         const unsigned char *tbs, size_t tbslen)
{
    PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;

    if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
        return 0;

    return ossl_sm2_internal_verify(tbs, tbslen, sig, siglen, ctx->ec);
}

static void free_md(PROV_SM2_CTX *ctx)
{
    EVP_MD_CTX_free(ctx->mdctx);
    EVP_MD_free(ctx->md);
    ctx->mdctx = NULL;
    ctx->md = NULL;
}

static int sm2sig_digest_signverify_init(void *vpsm2ctx, const char *mdname,
                                         void *ec, const OSSL_PARAM params[])
{
    PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;
    int md_nid;
    WPACKET pkt;
    int ret = 0;

    if (!sm2sig_signature_init(vpsm2ctx, ec, params)
        || !sm2sig_set_mdname(ctx, mdname))
        return ret;

    if (ctx->mdctx == NULL) {
        ctx->mdctx = EVP_MD_CTX_new();
        if (ctx->mdctx == NULL)
            goto error;
    }

    md_nid = EVP_MD_get_type(ctx->md);

    /*
     * We do not 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))
        && ossl_DER_w_algorithmIdentifier_SM2_with_MD(&pkt, -1, ctx->ec, md_nid)
        && WPACKET_finish(&pkt)) {
        WPACKET_get_total_written(&pkt, &ctx->aid_len);
        ctx->aid = WPACKET_get_curr(&pkt);
    }
    WPACKET_cleanup(&pkt);

    if (!EVP_DigestInit_ex2(ctx->mdctx, ctx->md, params))
        goto error;

    ctx->flag_compute_z_digest = 1;

    ret = 1;

 error:
    return ret;
}

static int sm2sig_compute_z_digest(PROV_SM2_CTX *ctx)
{
    uint8_t *z = NULL;
    int ret = 1;

    if (ctx->flag_compute_z_digest) {
        /* Only do this once */
        ctx->flag_compute_z_digest = 0;

        if ((z = OPENSSL_zalloc(ctx->mdsize)) == NULL
            /* get hashed prefix 'z' of tbs message */
            || !ossl_sm2_compute_z_digest(z, ctx->md, ctx->id, ctx->id_len,
                                          ctx->ec)
            || !EVP_DigestUpdate(ctx->mdctx, z, ctx->mdsize))
            ret = 0;
        OPENSSL_free(z);
    }

    return ret;
}

int sm2sig_digest_signverify_update(void *vpsm2ctx, const unsigned char *data,
                                    size_t datalen)
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;

    if (psm2ctx == NULL || psm2ctx->mdctx == NULL)
        return 0;

    return sm2sig_compute_z_digest(psm2ctx)
        && EVP_DigestUpdate(psm2ctx->mdctx, data, datalen);
}

int sm2sig_digest_sign_final(void *vpsm2ctx, unsigned char *sig, size_t *siglen,
                             size_t sigsize)
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
    unsigned char digest[EVP_MAX_MD_SIZE];
    unsigned int dlen = 0;

    if (psm2ctx == NULL || psm2ctx->mdctx == NULL)
        return 0;

    /*
     * If sig is NULL then we're just finding out the sig size. Other fields
     * are ignored. Defer to sm2sig_sign.
     */
    if (sig != NULL) {
        if (!(sm2sig_compute_z_digest(psm2ctx)
              && EVP_DigestFinal_ex(psm2ctx->mdctx, digest, &dlen)))
            return 0;
    }

    return sm2sig_sign(vpsm2ctx, sig, siglen, sigsize, digest, (size_t)dlen);
}


int sm2sig_digest_verify_final(void *vpsm2ctx, const unsigned char *sig,
                               size_t siglen)
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
    unsigned char digest[EVP_MAX_MD_SIZE];
    unsigned int dlen = 0;

    if (psm2ctx == NULL
        || psm2ctx->mdctx == NULL
        || EVP_MD_get_size(psm2ctx->md) > (int)sizeof(digest))
        return 0;

    if (!(sm2sig_compute_z_digest(psm2ctx)
          && EVP_DigestFinal_ex(psm2ctx->mdctx, digest, &dlen)))
        return 0;

    return sm2sig_verify(vpsm2ctx, sig, siglen, digest, (size_t)dlen);
}

static void sm2sig_freectx(void *vpsm2ctx)
{
    PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;

    free_md(ctx);
    EC_KEY_free(ctx->ec);
    OPENSSL_free(ctx->propq);
    OPENSSL_free(ctx->id);
    OPENSSL_free(ctx);
}

static void *sm2sig_dupctx(void *vpsm2ctx)
{
    PROV_SM2_CTX *srcctx = (PROV_SM2_CTX *)vpsm2ctx;
    PROV_SM2_CTX *dstctx;

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

    *dstctx = *srcctx;
    dstctx->ec = NULL;
    dstctx->propq = NULL;
    dstctx->md = NULL;
    dstctx->mdctx = NULL;
    dstctx->id = NULL;

    if (srcctx->ec != NULL && !EC_KEY_up_ref(srcctx->ec))
        goto err;
    dstctx->ec = srcctx->ec;

    if (srcctx->propq != NULL) {
        dstctx->propq = OPENSSL_strdup(srcctx->propq);
        if (dstctx->propq == NULL)
            goto err;
    }

    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;
    }

    if (srcctx->id != NULL) {
        dstctx->id = OPENSSL_malloc(srcctx->id_len);
        if (dstctx->id == NULL)
            goto err;
        dstctx->id_len = srcctx->id_len;
        memcpy(dstctx->id, srcctx->id, srcctx->id_len);
    }

    return dstctx;
 err:
    sm2sig_freectx(dstctx);
    return NULL;
}

static int sm2sig_get_ctx_params(void *vpsm2ctx, OSSL_PARAM *params)
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
    OSSL_PARAM *p;

    if (psm2ctx == NULL)
        return 0;

    p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
    if (p != NULL
        && !OSSL_PARAM_set_octet_string(p, psm2ctx->aid, psm2ctx->aid_len))
        return 0;

    p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
    if (p != NULL && !OSSL_PARAM_set_size_t(p, psm2ctx->mdsize))
        return 0;

    p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
    if (p != NULL && !OSSL_PARAM_set_utf8_string(p, psm2ctx->md == NULL
                                                    ? psm2ctx->mdname
                                                    : EVP_MD_get0_name(psm2ctx->md)))
        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_size_t(OSSL_SIGNATURE_PARAM_DIGEST_SIZE, NULL),
    OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
    OSSL_PARAM_END
};

static const OSSL_PARAM *sm2sig_gettable_ctx_params(ossl_unused void *vpsm2ctx,
                                                    ossl_unused void *provctx)
{
    return known_gettable_ctx_params;
}

static int sm2sig_set_ctx_params(void *vpsm2ctx, const OSSL_PARAM params[])
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
    const OSSL_PARAM *p;
    size_t mdsize;

    if (psm2ctx == NULL)
        return 0;
    if (params == NULL)
        return 1;

    p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_DIST_ID);
    if (p != NULL) {
        void *tmp_id = NULL;
        size_t tmp_idlen = 0;

        /*
         * If the 'z' digest has already been computed, the ID is set too late
         */
        if (!psm2ctx->flag_compute_z_digest)
            return 0;

        if (p->data_size != 0
            && !OSSL_PARAM_get_octet_string(p, &tmp_id, 0, &tmp_idlen))
            return 0;
        OPENSSL_free(psm2ctx->id);
        psm2ctx->id = tmp_id;
        psm2ctx->id_len = tmp_idlen;
    }

    /*
     * The following code checks that the size is the same as the SM3 digest
     * size returning an error otherwise.
     * If there is ever any different digest algorithm allowed with SM2
     * this needs to be adjusted accordingly.
     */
    p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
    if (p != NULL && (!OSSL_PARAM_get_size_t(p, &mdsize)
                      || mdsize != psm2ctx->mdsize))
        return 0;

    p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
    if (p != NULL) {
        char *mdname = NULL;

        if (!OSSL_PARAM_get_utf8_string(p, &mdname, 0))
            return 0;
        if (!sm2sig_set_mdname(psm2ctx, mdname)) {
            OPENSSL_free(mdname);
            return 0;
        }
        OPENSSL_free(mdname);
    }

    return 1;
}

static const OSSL_PARAM known_settable_ctx_params[] = {
    OSSL_PARAM_size_t(OSSL_SIGNATURE_PARAM_DIGEST_SIZE, NULL),
    OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
    OSSL_PARAM_octet_string(OSSL_PKEY_PARAM_DIST_ID, NULL, 0),
    OSSL_PARAM_END
};

static const OSSL_PARAM *sm2sig_settable_ctx_params(ossl_unused void *vpsm2ctx,
                                                    ossl_unused void *provctx)
{
    return known_settable_ctx_params;
}

static int sm2sig_get_ctx_md_params(void *vpsm2ctx, OSSL_PARAM *params)
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;

    if (psm2ctx->mdctx == NULL)
        return 0;

    return EVP_MD_CTX_get_params(psm2ctx->mdctx, params);
}

static const OSSL_PARAM *sm2sig_gettable_ctx_md_params(void *vpsm2ctx)
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;

    if (psm2ctx->md == NULL)
        return 0;

    return EVP_MD_gettable_ctx_params(psm2ctx->md);
}

static int sm2sig_set_ctx_md_params(void *vpsm2ctx, const OSSL_PARAM params[])
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;

    if (psm2ctx->mdctx == NULL)
        return 0;

    return EVP_MD_CTX_set_params(psm2ctx->mdctx, params);
}

static const OSSL_PARAM *sm2sig_settable_ctx_md_params(void *vpsm2ctx)
{
    PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;

    if (psm2ctx->md == NULL)
        return 0;

    return EVP_MD_settable_ctx_params(psm2ctx->md);
}

const OSSL_DISPATCH ossl_sm2_signature_functions[] = {
    { OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))sm2sig_newctx },
    { OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))sm2sig_signature_init },
    { OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))sm2sig_sign },
    { OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))sm2sig_signature_init },
    { OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))sm2sig_verify },
    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
      (void (*)(void))sm2sig_digest_signverify_init },
    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
      (void (*)(void))sm2sig_digest_signverify_update },
    { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
      (void (*)(void))sm2sig_digest_sign_final },
    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
      (void (*)(void))sm2sig_digest_signverify_init },
    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
      (void (*)(void))sm2sig_digest_signverify_update },
    { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
      (void (*)(void))sm2sig_digest_verify_final },
    { OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))sm2sig_freectx },
    { OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))sm2sig_dupctx },
    { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))sm2sig_get_ctx_params },
    { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
      (void (*)(void))sm2sig_gettable_ctx_params },
    { OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))sm2sig_set_ctx_params },
    { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
      (void (*)(void))sm2sig_settable_ctx_params },
    { OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
      (void (*)(void))sm2sig_get_ctx_md_params },
    { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
      (void (*)(void))sm2sig_gettable_ctx_md_params },
    { OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
      (void (*)(void))sm2sig_set_ctx_md_params },
    { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
      (void (*)(void))sm2sig_settable_ctx_md_params },
    { 0, NULL }
};

Coverage Report

Created: 2025-06-13 06:58

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2020-2022 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		* ECDSA low level APIs are deprecated for public use, but still ok for
12		* internal use - SM2 implementation uses ECDSA_size() function.
13		*/
14		#include "internal/deprecated.h"
15
16		#include <string.h> /* memcpy */
17		#include <openssl/crypto.h>
18		#include <openssl/core_dispatch.h>
19		#include <openssl/core_names.h>
20		#include <openssl/dsa.h>
21		#include <openssl/params.h>
22		#include <openssl/evp.h>
23		#include <openssl/err.h>
24		#include <openssl/proverr.h>
25		#include "internal/nelem.h"
26		#include "internal/sizes.h"
27		#include "internal/cryptlib.h"
28		#include "internal/sm3.h"
29		#include "prov/implementations.h"
30		#include "prov/providercommon.h"
31		#include "prov/provider_ctx.h"
32		#include "crypto/ec.h"
33		#include "crypto/sm2.h"
34		#include "prov/der_sm2.h"
35
36		static OSSL_FUNC_signature_newctx_fn sm2sig_newctx;
37		static OSSL_FUNC_signature_sign_init_fn sm2sig_signature_init;
38		static OSSL_FUNC_signature_verify_init_fn sm2sig_signature_init;
39		static OSSL_FUNC_signature_sign_fn sm2sig_sign;
40		static OSSL_FUNC_signature_verify_fn sm2sig_verify;
41		static OSSL_FUNC_signature_digest_sign_init_fn sm2sig_digest_signverify_init;
42		static OSSL_FUNC_signature_digest_sign_update_fn sm2sig_digest_signverify_update;
43		static OSSL_FUNC_signature_digest_sign_final_fn sm2sig_digest_sign_final;
44		static OSSL_FUNC_signature_digest_verify_init_fn sm2sig_digest_signverify_init;
45		static OSSL_FUNC_signature_digest_verify_update_fn sm2sig_digest_signverify_update;
46		static OSSL_FUNC_signature_digest_verify_final_fn sm2sig_digest_verify_final;
47		static OSSL_FUNC_signature_freectx_fn sm2sig_freectx;
48		static OSSL_FUNC_signature_dupctx_fn sm2sig_dupctx;
49		static OSSL_FUNC_signature_get_ctx_params_fn sm2sig_get_ctx_params;
50		static OSSL_FUNC_signature_gettable_ctx_params_fn sm2sig_gettable_ctx_params;
51		static OSSL_FUNC_signature_set_ctx_params_fn sm2sig_set_ctx_params;
52		static OSSL_FUNC_signature_settable_ctx_params_fn sm2sig_settable_ctx_params;
53		static OSSL_FUNC_signature_get_ctx_md_params_fn sm2sig_get_ctx_md_params;
54		static OSSL_FUNC_signature_gettable_ctx_md_params_fn sm2sig_gettable_ctx_md_params;
55		static OSSL_FUNC_signature_set_ctx_md_params_fn sm2sig_set_ctx_md_params;
56		static OSSL_FUNC_signature_settable_ctx_md_params_fn sm2sig_settable_ctx_md_params;
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 EC structures, so
61		* we use that here too.
62		*/
63		typedef struct {
64		OSSL_LIB_CTX *libctx;
65		char *propq;
66		EC_KEY *ec;
67
68		/*
69		* Flag to determine if the 'z' digest needs to be computed and fed to the
70		* hash function.
71		* This flag should be set on initialization and the computation should
72		* be performed only once, on first update.
73		*/
74		unsigned int flag_compute_z_digest : 1;
75
76		char mdname[OSSL_MAX_NAME_SIZE];
77
78		/* The Algorithm Identifier of the combined signature algorithm */
79		unsigned char aid_buf[OSSL_MAX_ALGORITHM_ID_SIZE];
80		unsigned char *aid;
81		size_t aid_len;
82
83		/* main digest */
84		EVP_MD *md;
85		EVP_MD_CTX *mdctx;
86		size_t mdsize;
87
88		/* SM2 ID used for calculating the Z value */
89		unsigned char *id;
90		size_t id_len;
91		} PROV_SM2_CTX;
92
93		static int sm2sig_set_mdname(PROV_SM2_CTX psm2ctx, const char mdname)
94	0	{
95	0	if (psm2ctx->md == NULL) /* We need an SM3 md to compare with */
96	0	psm2ctx->md = EVP_MD_fetch(psm2ctx->libctx, psm2ctx->mdname,
97	0	psm2ctx->propq);
98	0	if (psm2ctx->md == NULL)
99	0	return 0;
100
101	0	if (mdname == NULL)
102	0	return 1;
103
104	0	if (strlen(mdname) >= sizeof(psm2ctx->mdname)
105	0	\|\| !EVP_MD_is_a(psm2ctx->md, mdname)) {
106	0	ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST, "digest=%s",
107	0	mdname);
108	0	return 0;
109	0	}
110
111	0	OPENSSL_strlcpy(psm2ctx->mdname, mdname, sizeof(psm2ctx->mdname));
112	0	return 1;
113	0	}
114
115		static void sm2sig_newctx(void provctx, const char *propq)
116	0	{
117	0	PROV_SM2_CTX *ctx = OPENSSL_zalloc(sizeof(PROV_SM2_CTX));
118
119	0	if (ctx == NULL)
120	0	return NULL;
121
122	0	ctx->libctx = PROV_LIBCTX_OF(provctx);
123	0	if (propq != NULL && (ctx->propq = OPENSSL_strdup(propq)) == NULL) {
124	0	OPENSSL_free(ctx);
125	0	ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
126	0	return NULL;
127	0	}
128	0	ctx->mdsize = SM3_DIGEST_LENGTH;
129	0	strcpy(ctx->mdname, OSSL_DIGEST_NAME_SM3);
130	0	return ctx;
131	0	}
132
133		static int sm2sig_signature_init(void vpsm2ctx, void ec,
134		const OSSL_PARAM params[])
135	0	{
136	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
137
138	0	if (!ossl_prov_is_running()
139	0	\|\| psm2ctx == NULL)
140	0	return 0;
141
142	0	if (ec == NULL && psm2ctx->ec == NULL) {
143	0	ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
144	0	return 0;
145	0	}
146
147	0	if (ec != NULL) {
148	0	if (!EC_KEY_up_ref(ec))
149	0	return 0;
150	0	EC_KEY_free(psm2ctx->ec);
151	0	psm2ctx->ec = ec;
152	0	}
153
154	0	return sm2sig_set_ctx_params(psm2ctx, params);
155	0	}
156
157		static int sm2sig_sign(void vpsm2ctx, unsigned char sig, size_t *siglen,
158		size_t sigsize, const unsigned char *tbs, size_t tbslen)
159	0	{
160	0	PROV_SM2_CTX ctx = (PROV_SM2_CTX )vpsm2ctx;
161	0	int ret;
162	0	unsigned int sltmp;
163		/* SM2 uses ECDSA_size as well */
164	0	size_t ecsize = ECDSA_size(ctx->ec);
165
166	0	if (sig == NULL) {
167	0	*siglen = ecsize;
168	0	return 1;
169	0	}
170
171	0	if (sigsize < (size_t)ecsize)
172	0	return 0;
173
174	0	if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
175	0	return 0;
176
177	0	ret = ossl_sm2_internal_sign(tbs, tbslen, sig, &sltmp, ctx->ec);
178	0	if (ret <= 0)
179	0	return 0;
180
181	0	*siglen = sltmp;
182	0	return 1;
183	0	}
184
185		static int sm2sig_verify(void vpsm2ctx, const unsigned char sig, size_t siglen,
186		const unsigned char *tbs, size_t tbslen)
187	0	{
188	0	PROV_SM2_CTX ctx = (PROV_SM2_CTX )vpsm2ctx;
189
190	0	if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
191	0	return 0;
192
193	0	return ossl_sm2_internal_verify(tbs, tbslen, sig, siglen, ctx->ec);
194	0	}
195
196		static void free_md(PROV_SM2_CTX *ctx)
197	0	{
198	0	EVP_MD_CTX_free(ctx->mdctx);
199	0	EVP_MD_free(ctx->md);
200	0	ctx->mdctx = NULL;
201	0	ctx->md = NULL;
202	0	}
203
204		static int sm2sig_digest_signverify_init(void vpsm2ctx, const char mdname,
205		void *ec, const OSSL_PARAM params[])
206	0	{
207	0	PROV_SM2_CTX ctx = (PROV_SM2_CTX )vpsm2ctx;
208	0	int md_nid;
209	0	WPACKET pkt;
210	0	int ret = 0;
211
212	0	if (!sm2sig_signature_init(vpsm2ctx, ec, params)
213	0	\|\| !sm2sig_set_mdname(ctx, mdname))
214	0	return ret;
215
216	0	if (ctx->mdctx == NULL) {
217	0	ctx->mdctx = EVP_MD_CTX_new();
218	0	if (ctx->mdctx == NULL)
219	0	goto error;
220	0	}
221
222	0	md_nid = EVP_MD_get_type(ctx->md);
223
224		/*
225		* We do not care about DER writing errors.
226		* All it really means is that for some reason, there's no
227		* AlgorithmIdentifier to be had, but the operation itself is
228		* still valid, just as long as it's not used to construct
229		* anything that needs an AlgorithmIdentifier.
230		*/
231	0	ctx->aid_len = 0;
232	0	if (WPACKET_init_der(&pkt, ctx->aid_buf, sizeof(ctx->aid_buf))
233	0	&& ossl_DER_w_algorithmIdentifier_SM2_with_MD(&pkt, -1, ctx->ec, md_nid)
234	0	&& WPACKET_finish(&pkt)) {
235	0	WPACKET_get_total_written(&pkt, &ctx->aid_len);
236	0	ctx->aid = WPACKET_get_curr(&pkt);
237	0	}
238	0	WPACKET_cleanup(&pkt);
239
240	0	if (!EVP_DigestInit_ex2(ctx->mdctx, ctx->md, params))
241	0	goto error;
242
243	0	ctx->flag_compute_z_digest = 1;
244
245	0	ret = 1;
246
247	0	error:
248	0	return ret;
249	0	}
250
251		static int sm2sig_compute_z_digest(PROV_SM2_CTX *ctx)
252	0	{
253	0	uint8_t *z = NULL;
254	0	int ret = 1;
255
256	0	if (ctx->flag_compute_z_digest) {
257		/* Only do this once */
258	0	ctx->flag_compute_z_digest = 0;
259
260	0	if ((z = OPENSSL_zalloc(ctx->mdsize)) == NULL
261		/* get hashed prefix 'z' of tbs message */
262	0	\|\| !ossl_sm2_compute_z_digest(z, ctx->md, ctx->id, ctx->id_len,
263	0	ctx->ec)
264	0	\|\| !EVP_DigestUpdate(ctx->mdctx, z, ctx->mdsize))
265	0	ret = 0;
266	0	OPENSSL_free(z);
267	0	}
268
269	0	return ret;
270	0	}
271
272		int sm2sig_digest_signverify_update(void vpsm2ctx, const unsigned char data,
273		size_t datalen)
274	0	{
275	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
276
277	0	if (psm2ctx == NULL \|\| psm2ctx->mdctx == NULL)
278	0	return 0;
279
280	0	return sm2sig_compute_z_digest(psm2ctx)
281	0	&& EVP_DigestUpdate(psm2ctx->mdctx, data, datalen);
282	0	}
283
284		int sm2sig_digest_sign_final(void vpsm2ctx, unsigned char sig, size_t *siglen,
285		size_t sigsize)
286	0	{
287	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
288	0	unsigned char digest[EVP_MAX_MD_SIZE];
289	0	unsigned int dlen = 0;
290
291	0	if (psm2ctx == NULL \|\| psm2ctx->mdctx == NULL)
292	0	return 0;
293
294		/*
295		* If sig is NULL then we're just finding out the sig size. Other fields
296		* are ignored. Defer to sm2sig_sign.
297		*/
298	0	if (sig != NULL) {
299	0	if (!(sm2sig_compute_z_digest(psm2ctx)
300	0	&& EVP_DigestFinal_ex(psm2ctx->mdctx, digest, &dlen)))
301	0	return 0;
302	0	}
303
304	0	return sm2sig_sign(vpsm2ctx, sig, siglen, sigsize, digest, (size_t)dlen);
305	0	}
306
307
308		int sm2sig_digest_verify_final(void vpsm2ctx, const unsigned char sig,
309		size_t siglen)
310	0	{
311	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
312	0	unsigned char digest[EVP_MAX_MD_SIZE];
313	0	unsigned int dlen = 0;
314
315	0	if (psm2ctx == NULL
316	0	\|\| psm2ctx->mdctx == NULL
317	0	\|\| EVP_MD_get_size(psm2ctx->md) > (int)sizeof(digest))
318	0	return 0;
319
320	0	if (!(sm2sig_compute_z_digest(psm2ctx)
321	0	&& EVP_DigestFinal_ex(psm2ctx->mdctx, digest, &dlen)))
322	0	return 0;
323
324	0	return sm2sig_verify(vpsm2ctx, sig, siglen, digest, (size_t)dlen);
325	0	}
326
327		static void sm2sig_freectx(void *vpsm2ctx)
328	0	{
329	0	PROV_SM2_CTX ctx = (PROV_SM2_CTX )vpsm2ctx;
330
331	0	free_md(ctx);
332	0	EC_KEY_free(ctx->ec);
333	0	OPENSSL_free(ctx->propq);
334	0	OPENSSL_free(ctx->id);
335	0	OPENSSL_free(ctx);
336	0	}
337
338		static void sm2sig_dupctx(void vpsm2ctx)
339	0	{
340	0	PROV_SM2_CTX srcctx = (PROV_SM2_CTX )vpsm2ctx;
341	0	PROV_SM2_CTX *dstctx;
342
343	0	dstctx = OPENSSL_zalloc(sizeof(*srcctx));
344	0	if (dstctx == NULL)
345	0	return NULL;
346
347	0	dstctx = srcctx;
348	0	dstctx->ec = NULL;
349	0	dstctx->propq = NULL;
350	0	dstctx->md = NULL;
351	0	dstctx->mdctx = NULL;
352	0	dstctx->id = NULL;
353
354	0	if (srcctx->ec != NULL && !EC_KEY_up_ref(srcctx->ec))
355	0	goto err;
356	0	dstctx->ec = srcctx->ec;
357
358	0	if (srcctx->propq != NULL) {
359	0	dstctx->propq = OPENSSL_strdup(srcctx->propq);
360	0	if (dstctx->propq == NULL)
361	0	goto err;
362	0	}
363
364	0	if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
365	0	goto err;
366	0	dstctx->md = srcctx->md;
367
368	0	if (srcctx->mdctx != NULL) {
369	0	dstctx->mdctx = EVP_MD_CTX_new();
370	0	if (dstctx->mdctx == NULL
371	0	\|\| !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
372	0	goto err;
373	0	}
374
375	0	if (srcctx->id != NULL) {
376	0	dstctx->id = OPENSSL_malloc(srcctx->id_len);
377	0	if (dstctx->id == NULL)
378	0	goto err;
379	0	dstctx->id_len = srcctx->id_len;
380	0	memcpy(dstctx->id, srcctx->id, srcctx->id_len);
381	0	}
382
383	0	return dstctx;
384	0	err:
385	0	sm2sig_freectx(dstctx);
386	0	return NULL;
387	0	}
388
389		static int sm2sig_get_ctx_params(void vpsm2ctx, OSSL_PARAM params)
390	0	{
391	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
392	0	OSSL_PARAM *p;
393
394	0	if (psm2ctx == NULL)
395	0	return 0;
396
397	0	p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
398	0	if (p != NULL
399	0	&& !OSSL_PARAM_set_octet_string(p, psm2ctx->aid, psm2ctx->aid_len))
400	0	return 0;
401
402	0	p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
403	0	if (p != NULL && !OSSL_PARAM_set_size_t(p, psm2ctx->mdsize))
404	0	return 0;
405
406	0	p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
407	0	if (p != NULL && !OSSL_PARAM_set_utf8_string(p, psm2ctx->md == NULL
408	0	? psm2ctx->mdname
409	0	: EVP_MD_get0_name(psm2ctx->md)))
410	0	return 0;
411
412	0	return 1;
413	0	}
414
415		static const OSSL_PARAM known_gettable_ctx_params[] = {
416		OSSL_PARAM_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID, NULL, 0),
417		OSSL_PARAM_size_t(OSSL_SIGNATURE_PARAM_DIGEST_SIZE, NULL),
418		OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
419		OSSL_PARAM_END
420		};
421
422		static const OSSL_PARAM sm2sig_gettable_ctx_params(ossl_unused void vpsm2ctx,
423		ossl_unused void *provctx)
424	0	{
425	0	return known_gettable_ctx_params;
426	0	}
427
428		static int sm2sig_set_ctx_params(void *vpsm2ctx, const OSSL_PARAM params[])
429	0	{
430	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
431	0	const OSSL_PARAM *p;
432	0	size_t mdsize;
433
434	0	if (psm2ctx == NULL)
435	0	return 0;
436	0	if (params == NULL)
437	0	return 1;
438
439	0	p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_DIST_ID);
440	0	if (p != NULL) {
441	0	void *tmp_id = NULL;
442	0	size_t tmp_idlen = 0;
443
444		/*
445		* If the 'z' digest has already been computed, the ID is set too late
446		*/
447	0	if (!psm2ctx->flag_compute_z_digest)
448	0	return 0;
449
450	0	if (p->data_size != 0
451	0	&& !OSSL_PARAM_get_octet_string(p, &tmp_id, 0, &tmp_idlen))
452	0	return 0;
453	0	OPENSSL_free(psm2ctx->id);
454	0	psm2ctx->id = tmp_id;
455	0	psm2ctx->id_len = tmp_idlen;
456	0	}
457
458		/*
459		* The following code checks that the size is the same as the SM3 digest
460		* size returning an error otherwise.
461		* If there is ever any different digest algorithm allowed with SM2
462		* this needs to be adjusted accordingly.
463		*/
464	0	p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
465	0	if (p != NULL && (!OSSL_PARAM_get_size_t(p, &mdsize)
466	0	\|\| mdsize != psm2ctx->mdsize))
467	0	return 0;
468
469	0	p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
470	0	if (p != NULL) {
471	0	char *mdname = NULL;
472
473	0	if (!OSSL_PARAM_get_utf8_string(p, &mdname, 0))
474	0	return 0;
475	0	if (!sm2sig_set_mdname(psm2ctx, mdname)) {
476	0	OPENSSL_free(mdname);
477	0	return 0;
478	0	}
479	0	OPENSSL_free(mdname);
480	0	}
481
482	0	return 1;
483	0	}
484
485		static const OSSL_PARAM known_settable_ctx_params[] = {
486		OSSL_PARAM_size_t(OSSL_SIGNATURE_PARAM_DIGEST_SIZE, NULL),
487		OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
488		OSSL_PARAM_octet_string(OSSL_PKEY_PARAM_DIST_ID, NULL, 0),
489		OSSL_PARAM_END
490		};
491
492		static const OSSL_PARAM sm2sig_settable_ctx_params(ossl_unused void vpsm2ctx,
493		ossl_unused void *provctx)
494	1	{
495	1	return known_settable_ctx_params;
496	1	}
497
498		static int sm2sig_get_ctx_md_params(void vpsm2ctx, OSSL_PARAM params)
499	0	{
500	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
501
502	0	if (psm2ctx->mdctx == NULL)
503	0	return 0;
504
505	0	return EVP_MD_CTX_get_params(psm2ctx->mdctx, params);
506	0	}
507
508		static const OSSL_PARAM sm2sig_gettable_ctx_md_params(void vpsm2ctx)
509	0	{
510	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
511
512	0	if (psm2ctx->md == NULL)
513	0	return 0;
514
515	0	return EVP_MD_gettable_ctx_params(psm2ctx->md);
516	0	}
517
518		static int sm2sig_set_ctx_md_params(void *vpsm2ctx, const OSSL_PARAM params[])
519	0	{
520	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
521
522	0	if (psm2ctx->mdctx == NULL)
523	0	return 0;
524
525	0	return EVP_MD_CTX_set_params(psm2ctx->mdctx, params);
526	0	}
527
528		static const OSSL_PARAM sm2sig_settable_ctx_md_params(void vpsm2ctx)
529	0	{
530	0	PROV_SM2_CTX psm2ctx = (PROV_SM2_CTX )vpsm2ctx;
531
532	0	if (psm2ctx->md == NULL)
533	0	return 0;
534
535	0	return EVP_MD_settable_ctx_params(psm2ctx->md);
536	0	}
537
538		const OSSL_DISPATCH ossl_sm2_signature_functions[] = {
539		{ OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))sm2sig_newctx },
540		{ OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))sm2sig_signature_init },
541		{ OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))sm2sig_sign },
542		{ OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))sm2sig_signature_init },
543		{ OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))sm2sig_verify },
544		{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
545		(void (*)(void))sm2sig_digest_signverify_init },
546		{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
547		(void (*)(void))sm2sig_digest_signverify_update },
548		{ OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
549		(void (*)(void))sm2sig_digest_sign_final },
550		{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
551		(void (*)(void))sm2sig_digest_signverify_init },
552		{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
553		(void (*)(void))sm2sig_digest_signverify_update },
554		{ OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
555		(void (*)(void))sm2sig_digest_verify_final },
556		{ OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))sm2sig_freectx },
557		{ OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))sm2sig_dupctx },
558		{ OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))sm2sig_get_ctx_params },
559		{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
560		(void (*)(void))sm2sig_gettable_ctx_params },
561		{ OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))sm2sig_set_ctx_params },
562		{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
563		(void (*)(void))sm2sig_settable_ctx_params },
564		{ OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
565		(void (*)(void))sm2sig_get_ctx_md_params },
566		{ OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
567		(void (*)(void))sm2sig_gettable_ctx_md_params },
568		{ OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
569		(void (*)(void))sm2sig_set_ctx_md_params },
570		{ OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
571		(void (*)(void))sm2sig_settable_ctx_md_params },
572		{ 0, NULL }
573		};