xref: /freebsd/crypto/openssl/providers/implementations/signature/sm2_sig.c (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
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 implemetation 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 termine 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 compuation 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 {
95     if (psm2ctx->md == NULL) /* We need an SM3 md to compare with */
96         psm2ctx->md = EVP_MD_fetch(psm2ctx->libctx, psm2ctx->mdname,
97                                    psm2ctx->propq);
98     if (psm2ctx->md == NULL)
99         return 0;
100 
101     if (mdname == NULL)
102         return 1;
103 
104     if (strlen(mdname) >= sizeof(psm2ctx->mdname)
105         || !EVP_MD_is_a(psm2ctx->md, mdname)) {
106         ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST, "digest=%s",
107                        mdname);
108         return 0;
109     }
110 
111     OPENSSL_strlcpy(psm2ctx->mdname, mdname, sizeof(psm2ctx->mdname));
112     return 1;
113 }
114 
115 static void *sm2sig_newctx(void *provctx, const char *propq)
116 {
117     PROV_SM2_CTX *ctx = OPENSSL_zalloc(sizeof(PROV_SM2_CTX));
118 
119     if (ctx == NULL)
120         return NULL;
121 
122     ctx->libctx = PROV_LIBCTX_OF(provctx);
123     if (propq != NULL && (ctx->propq = OPENSSL_strdup(propq)) == NULL) {
124         OPENSSL_free(ctx);
125         ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
126         return NULL;
127     }
128     ctx->mdsize = SM3_DIGEST_LENGTH;
129     strcpy(ctx->mdname, OSSL_DIGEST_NAME_SM3);
130     return ctx;
131 }
132 
133 static int sm2sig_signature_init(void *vpsm2ctx, void *ec,
134                                  const OSSL_PARAM params[])
135 {
136     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
137 
138     if (!ossl_prov_is_running()
139             || psm2ctx == NULL)
140         return 0;
141 
142     if (ec == NULL && psm2ctx->ec == NULL) {
143         ERR_raise(ERR_LIB_PROV, PROV_R_NO_KEY_SET);
144         return 0;
145     }
146 
147     if (ec != NULL) {
148         if (!EC_KEY_up_ref(ec))
149             return 0;
150         EC_KEY_free(psm2ctx->ec);
151         psm2ctx->ec = ec;
152     }
153 
154     return sm2sig_set_ctx_params(psm2ctx, params);
155 }
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 {
160     PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;
161     int ret;
162     unsigned int sltmp;
163     /* SM2 uses ECDSA_size as well */
164     size_t ecsize = ECDSA_size(ctx->ec);
165 
166     if (sig == NULL) {
167         *siglen = ecsize;
168         return 1;
169     }
170 
171     if (sigsize < (size_t)ecsize)
172         return 0;
173 
174     if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
175         return 0;
176 
177     ret = ossl_sm2_internal_sign(tbs, tbslen, sig, &sltmp, ctx->ec);
178     if (ret <= 0)
179         return 0;
180 
181     *siglen = sltmp;
182     return 1;
183 }
184 
185 static int sm2sig_verify(void *vpsm2ctx, const unsigned char *sig, size_t siglen,
186                          const unsigned char *tbs, size_t tbslen)
187 {
188     PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;
189 
190     if (ctx->mdsize != 0 && tbslen != ctx->mdsize)
191         return 0;
192 
193     return ossl_sm2_internal_verify(tbs, tbslen, sig, siglen, ctx->ec);
194 }
195 
196 static void free_md(PROV_SM2_CTX *ctx)
197 {
198     EVP_MD_CTX_free(ctx->mdctx);
199     EVP_MD_free(ctx->md);
200     ctx->mdctx = NULL;
201     ctx->md = NULL;
202 }
203 
204 static int sm2sig_digest_signverify_init(void *vpsm2ctx, const char *mdname,
205                                          void *ec, const OSSL_PARAM params[])
206 {
207     PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;
208     int md_nid;
209     WPACKET pkt;
210     int ret = 0;
211 
212     if (!sm2sig_signature_init(vpsm2ctx, ec, params)
213         || !sm2sig_set_mdname(ctx, mdname))
214         return ret;
215 
216     if (ctx->mdctx == NULL) {
217         ctx->mdctx = EVP_MD_CTX_new();
218         if (ctx->mdctx == NULL)
219             goto error;
220     }
221 
222     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     ctx->aid_len = 0;
232     if (WPACKET_init_der(&pkt, ctx->aid_buf, sizeof(ctx->aid_buf))
233         && ossl_DER_w_algorithmIdentifier_SM2_with_MD(&pkt, -1, ctx->ec, md_nid)
234         && WPACKET_finish(&pkt)) {
235         WPACKET_get_total_written(&pkt, &ctx->aid_len);
236         ctx->aid = WPACKET_get_curr(&pkt);
237     }
238     WPACKET_cleanup(&pkt);
239 
240     if (!EVP_DigestInit_ex2(ctx->mdctx, ctx->md, params))
241         goto error;
242 
243     ctx->flag_compute_z_digest = 1;
244 
245     ret = 1;
246 
247  error:
248     return ret;
249 }
250 
251 static int sm2sig_compute_z_digest(PROV_SM2_CTX *ctx)
252 {
253     uint8_t *z = NULL;
254     int ret = 1;
255 
256     if (ctx->flag_compute_z_digest) {
257         /* Only do this once */
258         ctx->flag_compute_z_digest = 0;
259 
260         if ((z = OPENSSL_zalloc(ctx->mdsize)) == NULL
261             /* get hashed prefix 'z' of tbs message */
262             || !ossl_sm2_compute_z_digest(z, ctx->md, ctx->id, ctx->id_len,
263                                           ctx->ec)
264             || !EVP_DigestUpdate(ctx->mdctx, z, ctx->mdsize))
265             ret = 0;
266         OPENSSL_free(z);
267     }
268 
269     return ret;
270 }
271 
272 int sm2sig_digest_signverify_update(void *vpsm2ctx, const unsigned char *data,
273                                     size_t datalen)
274 {
275     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
276 
277     if (psm2ctx == NULL || psm2ctx->mdctx == NULL)
278         return 0;
279 
280     return sm2sig_compute_z_digest(psm2ctx)
281         && EVP_DigestUpdate(psm2ctx->mdctx, data, datalen);
282 }
283 
284 int sm2sig_digest_sign_final(void *vpsm2ctx, unsigned char *sig, size_t *siglen,
285                              size_t sigsize)
286 {
287     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
288     unsigned char digest[EVP_MAX_MD_SIZE];
289     unsigned int dlen = 0;
290 
291     if (psm2ctx == NULL || psm2ctx->mdctx == NULL)
292         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     if (sig != NULL) {
299         if (!(sm2sig_compute_z_digest(psm2ctx)
300               && EVP_DigestFinal_ex(psm2ctx->mdctx, digest, &dlen)))
301             return 0;
302     }
303 
304     return sm2sig_sign(vpsm2ctx, sig, siglen, sigsize, digest, (size_t)dlen);
305 }
306 
307 
308 int sm2sig_digest_verify_final(void *vpsm2ctx, const unsigned char *sig,
309                                size_t siglen)
310 {
311     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
312     unsigned char digest[EVP_MAX_MD_SIZE];
313     unsigned int dlen = 0;
314 
315     if (psm2ctx == NULL
316         || psm2ctx->mdctx == NULL
317         || EVP_MD_get_size(psm2ctx->md) > (int)sizeof(digest))
318         return 0;
319 
320     if (!(sm2sig_compute_z_digest(psm2ctx)
321           && EVP_DigestFinal_ex(psm2ctx->mdctx, digest, &dlen)))
322         return 0;
323 
324     return sm2sig_verify(vpsm2ctx, sig, siglen, digest, (size_t)dlen);
325 }
326 
327 static void sm2sig_freectx(void *vpsm2ctx)
328 {
329     PROV_SM2_CTX *ctx = (PROV_SM2_CTX *)vpsm2ctx;
330 
331     free_md(ctx);
332     EC_KEY_free(ctx->ec);
333     OPENSSL_free(ctx->propq);
334     OPENSSL_free(ctx->id);
335     OPENSSL_free(ctx);
336 }
337 
338 static void *sm2sig_dupctx(void *vpsm2ctx)
339 {
340     PROV_SM2_CTX *srcctx = (PROV_SM2_CTX *)vpsm2ctx;
341     PROV_SM2_CTX *dstctx;
342 
343     dstctx = OPENSSL_zalloc(sizeof(*srcctx));
344     if (dstctx == NULL)
345         return NULL;
346 
347     *dstctx = *srcctx;
348     dstctx->ec = NULL;
349     dstctx->propq = NULL;
350     dstctx->md = NULL;
351     dstctx->mdctx = NULL;
352     dstctx->id = NULL;
353 
354     if (srcctx->ec != NULL && !EC_KEY_up_ref(srcctx->ec))
355         goto err;
356     dstctx->ec = srcctx->ec;
357 
358     if (srcctx->propq != NULL) {
359         dstctx->propq = OPENSSL_strdup(srcctx->propq);
360         if (dstctx->propq == NULL)
361             goto err;
362     }
363 
364     if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
365         goto err;
366     dstctx->md = srcctx->md;
367 
368     if (srcctx->mdctx != NULL) {
369         dstctx->mdctx = EVP_MD_CTX_new();
370         if (dstctx->mdctx == NULL
371                 || !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
372             goto err;
373     }
374 
375     if (srcctx->id != NULL) {
376         dstctx->id = OPENSSL_malloc(srcctx->id_len);
377         if (dstctx->id == NULL)
378             goto err;
379         dstctx->id_len = srcctx->id_len;
380         memcpy(dstctx->id, srcctx->id, srcctx->id_len);
381     }
382 
383     return dstctx;
384  err:
385     sm2sig_freectx(dstctx);
386     return NULL;
387 }
388 
389 static int sm2sig_get_ctx_params(void *vpsm2ctx, OSSL_PARAM *params)
390 {
391     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
392     OSSL_PARAM *p;
393 
394     if (psm2ctx == NULL)
395         return 0;
396 
397     p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
398     if (p != NULL
399         && !OSSL_PARAM_set_octet_string(p, psm2ctx->aid, psm2ctx->aid_len))
400         return 0;
401 
402     p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
403     if (p != NULL && !OSSL_PARAM_set_size_t(p, psm2ctx->mdsize))
404         return 0;
405 
406     p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
407     if (p != NULL && !OSSL_PARAM_set_utf8_string(p, psm2ctx->md == NULL
408                                                     ? psm2ctx->mdname
409                                                     : EVP_MD_get0_name(psm2ctx->md)))
410         return 0;
411 
412     return 1;
413 }
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 {
425     return known_gettable_ctx_params;
426 }
427 
428 static int sm2sig_set_ctx_params(void *vpsm2ctx, const OSSL_PARAM params[])
429 {
430     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
431     const OSSL_PARAM *p;
432     size_t mdsize;
433 
434     if (psm2ctx == NULL)
435         return 0;
436     if (params == NULL)
437         return 1;
438 
439     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_DIST_ID);
440     if (p != NULL) {
441         void *tmp_id = NULL;
442         size_t tmp_idlen = 0;
443 
444         /*
445          * If the 'z' digest has already been computed, the ID is set too late
446          */
447         if (!psm2ctx->flag_compute_z_digest)
448             return 0;
449 
450         if (p->data_size != 0
451             && !OSSL_PARAM_get_octet_string(p, &tmp_id, 0, &tmp_idlen))
452             return 0;
453         OPENSSL_free(psm2ctx->id);
454         psm2ctx->id = tmp_id;
455         psm2ctx->id_len = tmp_idlen;
456     }
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     p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST_SIZE);
465     if (p != NULL && (!OSSL_PARAM_get_size_t(p, &mdsize)
466                       || mdsize != psm2ctx->mdsize))
467         return 0;
468 
469     p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
470     if (p != NULL) {
471         char *mdname = NULL;
472 
473         if (!OSSL_PARAM_get_utf8_string(p, &mdname, 0))
474             return 0;
475         if (!sm2sig_set_mdname(psm2ctx, mdname)) {
476             OPENSSL_free(mdname);
477             return 0;
478         }
479         OPENSSL_free(mdname);
480     }
481 
482     return 1;
483 }
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 {
495     return known_settable_ctx_params;
496 }
497 
498 static int sm2sig_get_ctx_md_params(void *vpsm2ctx, OSSL_PARAM *params)
499 {
500     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
501 
502     if (psm2ctx->mdctx == NULL)
503         return 0;
504 
505     return EVP_MD_CTX_get_params(psm2ctx->mdctx, params);
506 }
507 
508 static const OSSL_PARAM *sm2sig_gettable_ctx_md_params(void *vpsm2ctx)
509 {
510     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
511 
512     if (psm2ctx->md == NULL)
513         return 0;
514 
515     return EVP_MD_gettable_ctx_params(psm2ctx->md);
516 }
517 
518 static int sm2sig_set_ctx_md_params(void *vpsm2ctx, const OSSL_PARAM params[])
519 {
520     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
521 
522     if (psm2ctx->mdctx == NULL)
523         return 0;
524 
525     return EVP_MD_CTX_set_params(psm2ctx->mdctx, params);
526 }
527 
528 static const OSSL_PARAM *sm2sig_settable_ctx_md_params(void *vpsm2ctx)
529 {
530     PROV_SM2_CTX *psm2ctx = (PROV_SM2_CTX *)vpsm2ctx;
531 
532     if (psm2ctx->md == NULL)
533         return 0;
534 
535     return EVP_MD_settable_ctx_params(psm2ctx->md);
536 }
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 };
574