providers/implementations/keymgmt/dh_kmgmt.c

   1 /*
   2  * Copyright 2019-2020 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  * DH low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <string.h> /* strcmp */
  17 #include <openssl/core_numbers.h>
  18 #include <openssl/core_names.h>
  19 #include <openssl/bn.h>
  20 #include <openssl/err.h>
  21 #include "prov/implementations.h"
  22 #include "prov/providercommon.h"
  23 #include "prov/provider_ctx.h"
  24 #include "crypto/dh.h"
  25 #include "internal/sizes.h"
  26 #include "internal/nelem.h"
  27 #include "internal/param_build_set.h"
  28
  29 static OSSL_OP_keymgmt_new_fn dh_newdata;
  30 static OSSL_OP_keymgmt_free_fn dh_freedata;
  31 static OSSL_OP_keymgmt_gen_init_fn dh_gen_init;
  32 static OSSL_OP_keymgmt_gen_set_template_fn dh_gen_set_template;
  33 static OSSL_OP_keymgmt_gen_set_params_fn dh_gen_set_params;
  34 static OSSL_OP_keymgmt_gen_settable_params_fn dh_gen_settable_params;
  35 static OSSL_OP_keymgmt_gen_fn dh_gen;
  36 static OSSL_OP_keymgmt_gen_cleanup_fn dh_gen_cleanup;
  37 static OSSL_OP_keymgmt_get_params_fn dh_get_params;
  38 static OSSL_OP_keymgmt_gettable_params_fn dh_gettable_params;
  39 static OSSL_OP_keymgmt_has_fn dh_has;
  40 static OSSL_OP_keymgmt_match_fn dh_match;
  41 static OSSL_OP_keymgmt_validate_fn dh_validate;
  42 static OSSL_OP_keymgmt_import_fn dh_import;
  43 static OSSL_OP_keymgmt_import_types_fn dh_import_types;
  44 static OSSL_OP_keymgmt_export_fn dh_export;
  45 static OSSL_OP_keymgmt_export_types_fn dh_export_types;
  46
  47 #define DH_POSSIBLE_SELECTIONS                                                 \
  48     (OSSL_KEYMGMT_SELECT_KEYPAIR | OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS)
  49
  50 struct dh_gen_ctx {
  51     OPENSSL_CTX *libctx;
  52
  53     FFC_PARAMS *ffc_params;
  54     int selection;
  55     /* All these parameters are used for parameter generation only */
  56     /* If there is a group name then the remaining parameters are not needed */
  57     int group_nid;
  58     size_t pbits;
  59     size_t qbits;
  60     EVP_MD *md;
  61     unsigned char *seed; /* optional FIPS186-4 param for testing */
  62     size_t seedlen;
  63     int gindex; /* optional  FIPS186-4 generator index (ignored if -1) */
  64     int gen_type; /* see dhtype2id */
  65     int generator; /* Used by DH_PARAMGEN_TYPE_GENERATOR in non fips mode only */
  66     int pcounter;
  67     int hindex;
  68     int priv_len;
  69
  70     OSSL_CALLBACK *cb;
  71     void *cbarg;
  72 };
  73
  74 typedef struct dh_name2id_st{
  75     const char *name;
  76     int id;
  77 } DH_GENTYPE_NAME2ID;
  78
  79 static const DH_GENTYPE_NAME2ID dhtype2id[]=
  80 {
  81     { "default", DH_PARAMGEN_TYPE_FIPS_186_4 },
  82     { "fips186_4", DH_PARAMGEN_TYPE_FIPS_186_4 },
  83     { "fips186_2", DH_PARAMGEN_TYPE_FIPS_186_2 },
  84     { "group", DH_PARAMGEN_TYPE_GROUP },
  85     { "generator", DH_PARAMGEN_TYPE_GENERATOR }
  86 };
  87
  88 const char *dh_gen_type_id2name(int id)
  89 {
  90     size_t i;
  91
  92     for (i = 0; i < OSSL_NELEM(dhtype2id); ++i) {
  93         if (dhtype2id[i].id == id)
  94             return dhtype2id[i].name;
  95     }
  96     return NULL;
  97 }
  98
  99 static int dh_gen_type_name2id(const char *name)
 100 {
 101     size_t i;
 102
 103     for (i = 0; i < OSSL_NELEM(dhtype2id); ++i) {
 104         if (strcmp(dhtype2id[i].name, name) == 0)
 105             return dhtype2id[i].id;
 106     }
 107     return -1;
 108 }
 109
 110 static int dh_key_todata(DH *dh, OSSL_PARAM_BLD *bld, OSSL_PARAM params[])
 111 {
 112     const BIGNUM *priv = NULL, *pub = NULL;
 113
 114     if (dh == NULL)
 115         return 0;
 116
 117     DH_get0_key(dh, &pub, &priv);
 118     if (priv != NULL
 119         && !ossl_param_build_set_bn(bld, params, OSSL_PKEY_PARAM_PRIV_KEY, priv))
 120         return 0;
 121     if (pub != NULL
 122         && !ossl_param_build_set_bn(bld, params, OSSL_PKEY_PARAM_PUB_KEY, pub))
 123         return 0;
 124
 125     return 1;
 126 }
 127
 128 static void *dh_newdata(void *provctx)
 129 {
 130     return dh_new_with_libctx(PROV_LIBRARY_CONTEXT_OF(provctx));
 131 }
 132
 133 static void dh_freedata(void *keydata)
 134 {
 135     DH_free(keydata);
 136 }
 137
 138 static int dh_has(void *keydata, int selection)
 139 {
 140     DH *dh = keydata;
 141     int ok = 0;
 142
 143     if (dh != NULL) {
 144         if ((selection & DH_POSSIBLE_SELECTIONS) != 0)
 145             ok = 1;
 146
 147         if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
 148             ok = ok && (DH_get0_pub_key(dh) != NULL);
 149         if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
 150             ok = ok && (DH_get0_priv_key(dh) != NULL);
 151         if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0)
 152             ok = ok && (DH_get0_p(dh) != NULL && DH_get0_g(dh) != NULL);
 153     }
 154     return ok;
 155 }
 156
 157 static int dh_match(const void *keydata1, const void *keydata2, int selection)
 158 {
 159     const DH *dh1 = keydata1;
 160     const DH *dh2 = keydata2;
 161     int ok = 1;
 162
 163     if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
 164         ok = ok && BN_cmp(DH_get0_pub_key(dh1), DH_get0_pub_key(dh2)) == 0;
 165     if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
 166         ok = ok && BN_cmp(DH_get0_priv_key(dh1), DH_get0_priv_key(dh2)) == 0;
 167     if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0) {
 168         FFC_PARAMS *dhparams1 = dh_get0_params((DH *)dh1);
 169         FFC_PARAMS *dhparams2 = dh_get0_params((DH *)dh2);
 170
 171         ok = ok && ffc_params_cmp(dhparams1, dhparams2, 1);
 172     }
 173     return ok;
 174 }
 175
 176 static int dh_import(void *keydata, int selection, const OSSL_PARAM params[])
 177 {
 178     DH *dh = keydata;
 179     int ok = 1;
 180
 181     if (dh == NULL)
 182         return 0;
 183
 184     if ((selection & DH_POSSIBLE_SELECTIONS) == 0)
 185         return 0;
 186
 187     if ((selection & OSSL_KEYMGMT_SELECT_ALL_PARAMETERS) != 0)
 188         ok = ok && dh_ffc_params_fromdata(dh, params);
 189
 190     if ((selection & OSSL_KEYMGMT_SELECT_KEYPAIR) != 0)
 191         ok = ok && dh_key_fromdata(dh, params);
 192
 193     return ok;
 194 }
 195
 196 static int dh_export(void *keydata, int selection, OSSL_CALLBACK *param_cb,
 197                      void *cbarg)
 198 {
 199     DH *dh = keydata;
 200     OSSL_PARAM_BLD *tmpl = NULL;
 201     OSSL_PARAM *params = NULL;
 202     int ok = 1;
 203
 204     if (dh == NULL)
 205         return 0;
 206
 207     tmpl = OSSL_PARAM_BLD_new();
 208     if (tmpl == NULL)
 209         return 0;
 210
 211     if ((selection & OSSL_KEYMGMT_SELECT_ALL_PARAMETERS) != 0)
 212         ok = ok && ffc_params_todata(dh_get0_params(dh), tmpl, NULL);
 213     if ((selection & OSSL_KEYMGMT_SELECT_KEYPAIR) != 0)
 214         ok = ok && dh_key_todata(dh, tmpl, NULL);
 215
 216     if (!ok
 217         || (params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL) {
 218         ok = 0;
 219         goto err;
 220     }
 221     ok = param_cb(params, cbarg);
 222     OSSL_PARAM_BLD_free_params(params);
 223 err:
 224     OSSL_PARAM_BLD_free(tmpl);
 225     return ok;
 226 }
 227
 228 /* IMEXPORT = IMPORT + EXPORT */
 229
 230 # define DH_IMEXPORTABLE_PARAMETERS                                            \
 231     OSSL_PARAM_BN(OSSL_PKEY_PARAM_FFC_P, NULL, 0),                             \
 232     OSSL_PARAM_BN(OSSL_PKEY_PARAM_FFC_Q, NULL, 0),                             \
 233     OSSL_PARAM_BN(OSSL_PKEY_PARAM_FFC_G, NULL, 0),                             \
 234     OSSL_PARAM_BN(OSSL_PKEY_PARAM_FFC_COFACTOR, NULL, 0),                      \
 235     OSSL_PARAM_int(OSSL_PKEY_PARAM_FFC_GINDEX, NULL),                          \
 236     OSSL_PARAM_int(OSSL_PKEY_PARAM_FFC_PCOUNTER, NULL),                        \
 237     OSSL_PARAM_int(OSSL_PKEY_PARAM_FFC_H, NULL),                               \
 238     OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_FFC_GROUP, NULL, 0),                \
 239     OSSL_PARAM_octet_string(OSSL_PKEY_PARAM_FFC_SEED, NULL, 0)
 240 # define DH_IMEXPORTABLE_PUBLIC_KEY                                            \
 241     OSSL_PARAM_BN(OSSL_PKEY_PARAM_PUB_KEY, NULL, 0)
 242 # define DH_IMEXPORTABLE_PRIVATE_KEY                                           \
 243     OSSL_PARAM_BN(OSSL_PKEY_PARAM_PRIV_KEY, NULL, 0)
 244 static const OSSL_PARAM dh_all_types[] = {
 245     DH_IMEXPORTABLE_PARAMETERS,
 246     DH_IMEXPORTABLE_PUBLIC_KEY,
 247     DH_IMEXPORTABLE_PRIVATE_KEY,
 248     OSSL_PARAM_END
 249 };
 250 static const OSSL_PARAM dh_parameter_types[] = {
 251     DH_IMEXPORTABLE_PARAMETERS,
 252     OSSL_PARAM_END
 253 };
 254 static const OSSL_PARAM dh_key_types[] = {
 255     DH_IMEXPORTABLE_PUBLIC_KEY,
 256     DH_IMEXPORTABLE_PRIVATE_KEY,
 257     OSSL_PARAM_END
 258 };
 259 static const OSSL_PARAM *dh_types[] = {
 260     NULL,                        /* Index 0 = none of them */
 261     dh_parameter_types,          /* Index 1 = parameter types */
 262     dh_key_types,                /* Index 2 = key types */
 263     dh_all_types                 /* Index 3 = 1 + 2 */
 264 };
 265
 266 static const OSSL_PARAM *dh_imexport_types(int selection)
 267 {
 268     int type_select = 0;
 269
 270     if ((selection & OSSL_KEYMGMT_SELECT_ALL_PARAMETERS) != 0)
 271         type_select += 1;
 272     if ((selection & OSSL_KEYMGMT_SELECT_KEYPAIR) != 0)
 273         type_select += 2;
 274     return dh_types[type_select];
 275 }
 276
 277 static const OSSL_PARAM *dh_import_types(int selection)
 278 {
 279     return dh_imexport_types(selection);
 280 }
 281
 282 static const OSSL_PARAM *dh_export_types(int selection)
 283 {
 284     return dh_imexport_types(selection);
 285 }
 286
 287 static ossl_inline int dh_get_params(void *key, OSSL_PARAM params[])
 288 {
 289     DH *dh = key;
 290     OSSL_PARAM *p;
 291
 292     if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_BITS)) != NULL
 293         && !OSSL_PARAM_set_int(p, DH_bits(dh)))
 294         return 0;
 295     if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_SECURITY_BITS)) != NULL
 296         && !OSSL_PARAM_set_int(p, DH_security_bits(dh)))
 297         return 0;
 298     if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_MAX_SIZE)) != NULL
 299         && !OSSL_PARAM_set_int(p, DH_size(dh)))
 300         return 0;
 301     return ffc_params_todata(dh_get0_params(dh), NULL, params)
 302            && dh_key_todata(dh, NULL, params);
 303 }
 304
 305 static const OSSL_PARAM dh_params[] = {
 306     OSSL_PARAM_int(OSSL_PKEY_PARAM_BITS, NULL),
 307     OSSL_PARAM_int(OSSL_PKEY_PARAM_SECURITY_BITS, NULL),
 308     OSSL_PARAM_int(OSSL_PKEY_PARAM_MAX_SIZE, NULL),
 309     DH_IMEXPORTABLE_PARAMETERS,
 310     DH_IMEXPORTABLE_PUBLIC_KEY,
 311     DH_IMEXPORTABLE_PRIVATE_KEY,
 312     OSSL_PARAM_END
 313 };
 314
 315 static const OSSL_PARAM *dh_gettable_params(void)
 316 {
 317     return dh_params;
 318 }
 319
 320 static int dh_validate_public(DH *dh)
 321 {
 322     const BIGNUM *pub_key = NULL;
 323
 324     DH_get0_key(dh, &pub_key, NULL);
 325     return DH_check_pub_key_ex(dh, pub_key);
 326 }
 327
 328 static int dh_validate_private(DH *dh)
 329 {
 330     int status = 0;
 331     const BIGNUM *priv_key = NULL;
 332
 333     DH_get0_key(dh, NULL, &priv_key);
 334     return dh_check_priv_key(dh, priv_key, &status);;
 335 }
 336
 337 static int dh_validate(void *keydata, int selection)
 338 {
 339     DH *dh = keydata;
 340     int ok = 0;
 341
 342     if ((selection & DH_POSSIBLE_SELECTIONS) != 0)
 343         ok = 1;
 344
 345     if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0)
 346         ok = ok && DH_check_params_ex(dh);
 347
 348     if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
 349         ok = ok && dh_validate_public(dh);
 350
 351     if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
 352         ok = ok && dh_validate_private(dh);
 353
 354     if ((selection & OSSL_KEYMGMT_SELECT_KEYPAIR)
 355             == OSSL_KEYMGMT_SELECT_KEYPAIR)
 356         ok = ok && dh_check_pairwise(dh);
 357     return ok;
 358 }
 359
 360 static void *dh_gen_init(void *provctx, int selection)
 361 {
 362     OPENSSL_CTX *libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
 363     struct dh_gen_ctx *gctx = NULL;
 364
 365     if ((selection & (OSSL_KEYMGMT_SELECT_KEYPAIR
 366                       | OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS)) == 0)
 367         return NULL;
 368
 369     if ((gctx = OPENSSL_zalloc(sizeof(*gctx))) != NULL) {
 370         gctx->selection = selection;
 371         gctx->libctx = libctx;
 372         gctx->pbits = 2048;
 373         gctx->qbits = 224;
 374         gctx->md = NULL;
 375         gctx->gen_type = DH_PARAMGEN_TYPE_FIPS_186_4;
 376         gctx->gindex = -1;
 377         gctx->hindex = 0;
 378         gctx->pcounter = -1;
 379         gctx->generator = DH_GENERATOR_2;
 380     }
 381     return gctx;
 382 }
 383
 384 static int dh_gen_set_template(void *genctx, void *templ)
 385 {
 386     struct dh_gen_ctx *gctx = genctx;
 387     DH *dh = templ;
 388
 389     if (gctx == NULL || dh == NULL)
 390         return 0;
 391     gctx->ffc_params = dh_get0_params(dh);
 392     return 1;
 393 }
 394
 395 static int dh_set_gen_seed(struct dh_gen_ctx *gctx, unsigned char *seed,
 396                            size_t seedlen)
 397 {
 398     OPENSSL_clear_free(gctx->seed, gctx->seedlen);
 399     gctx->seed = NULL;
 400     gctx->seedlen = 0;
 401     if (seed != NULL && seedlen > 0) {
 402         gctx->seed = OPENSSL_memdup(seed, seedlen);
 403         if (gctx->seed == NULL)
 404             return 0;
 405         gctx->seedlen = seedlen;
 406     }
 407     return 1;
 408 }
 409
 410 static int dh_gen_set_params(void *genctx, const OSSL_PARAM params[])
 411 {
 412     struct dh_gen_ctx *gctx = genctx;
 413     const OSSL_PARAM *p;
 414
 415     if (gctx == NULL)
 416         return 0;
 417
 418     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_TYPE);
 419     if (p != NULL) {
 420         if (p->data_type != OSSL_PARAM_UTF8_STRING
 421             || ((gctx->gen_type = dh_gen_type_name2id(p->data)) == -1)) {
 422             ERR_raise(ERR_LIB_PROV, ERR_R_PASSED_INVALID_ARGUMENT);
 423             return 0;
 424         }
 425     }
 426     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_GROUP);
 427     if (p != NULL) {
 428         if (p->data_type != OSSL_PARAM_UTF8_STRING
 429            || ((gctx->group_nid = ffc_named_group_to_uid(p->data)) == NID_undef)) {
 430             ERR_raise(ERR_LIB_PROV, ERR_R_PASSED_INVALID_ARGUMENT);
 431             return 0;
 432         }
 433         gctx->gen_type = DH_PARAMGEN_TYPE_GROUP;
 434     }
 435     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_GENERATOR);
 436     if (p != NULL && !OSSL_PARAM_get_int(p, &gctx->generator))
 437         return 0;
 438     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_GINDEX);
 439     if (p != NULL && !OSSL_PARAM_get_int(p, &gctx->gindex))
 440         return 0;
 441     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_PCOUNTER);
 442     if (p != NULL && !OSSL_PARAM_get_int(p, &gctx->pcounter))
 443         return 0;
 444     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_H);
 445     if (p != NULL && !OSSL_PARAM_get_int(p, &gctx->hindex))
 446         return 0;
 447     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_SEED);
 448     if (p != NULL
 449         && (p->data_type != OSSL_PARAM_OCTET_STRING
 450             || !dh_set_gen_seed(gctx, p->data, p->data_size)))
 451             return 0;
 452
 453     if ((p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_PBITS)) != NULL
 454         && !OSSL_PARAM_get_size_t(p, &gctx->pbits))
 455         return 0;
 456     if ((p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_QBITS)) != NULL
 457         && !OSSL_PARAM_get_size_t(p, &gctx->qbits))
 458         return 0;
 459     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_DIGEST);
 460     if (p != NULL) {
 461         const OSSL_PARAM *p1;
 462         char mdprops[OSSL_MAX_PROPQUERY_SIZE] = { '\0' };
 463         char *str = mdprops;
 464
 465         if (p->data_type != OSSL_PARAM_UTF8_STRING)
 466             return 0;
 467         p1 = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_FFC_DIGEST_PROPS);
 468         if (p1 != NULL
 469             && !OSSL_PARAM_get_utf8_string(p1, &str, sizeof(mdprops)))
 470             return 0;
 471         EVP_MD_free(gctx->md);
 472         gctx->md = EVP_MD_fetch(gctx->libctx, p->data, mdprops);
 473         if (gctx->md == NULL)
 474             return 0;
 475     }
 476     p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_DH_PRIV_LEN);
 477     if (p != NULL && !OSSL_PARAM_get_int(p, &gctx->priv_len))
 478         return 0;
 479     return 1;
 480 }
 481
 482 static const OSSL_PARAM *dh_gen_settable_params(void *provctx)
 483 {
 484     static OSSL_PARAM settable[] = {
 485         OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_FFC_GROUP, NULL, 0),
 486         OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_FFC_TYPE, NULL, 0),
 487         OSSL_PARAM_size_t(OSSL_PKEY_PARAM_FFC_PBITS, NULL),
 488         OSSL_PARAM_size_t(OSSL_PKEY_PARAM_FFC_QBITS, NULL),
 489         OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_FFC_DIGEST, NULL, 0),
 490         OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_FFC_DIGEST_PROPS, NULL, 0),
 491         OSSL_PARAM_int(OSSL_PKEY_PARAM_FFC_GINDEX, NULL),
 492         OSSL_PARAM_octet_string(OSSL_PKEY_PARAM_FFC_SEED, NULL, 0),
 493         OSSL_PARAM_int(OSSL_PKEY_PARAM_FFC_GENERATOR, NULL),
 494         OSSL_PARAM_int(OSSL_PKEY_PARAM_FFC_PCOUNTER, NULL),
 495         OSSL_PARAM_int(OSSL_PKEY_PARAM_FFC_H, NULL),
 496         OSSL_PARAM_int(OSSL_PKEY_PARAM_DH_PRIV_LEN, NULL),
 497         OSSL_PARAM_END
 498     };
 499     return settable;
 500 }
 501
 502 static int dh_gencb(int p, int n, BN_GENCB *cb)
 503 {
 504     struct dh_gen_ctx *gctx = BN_GENCB_get_arg(cb);
 505     OSSL_PARAM params[] = { OSSL_PARAM_END, OSSL_PARAM_END, OSSL_PARAM_END };
 506
 507     params[0] = OSSL_PARAM_construct_int(OSSL_GEN_PARAM_POTENTIAL, &p);
 508     params[1] = OSSL_PARAM_construct_int(OSSL_GEN_PARAM_ITERATION, &n);
 509
 510     return gctx->cb(params, gctx->cbarg);
 511 }
 512
 513 static void *dh_gen(void *genctx, OSSL_CALLBACK *osslcb, void *cbarg)
 514 {
 515     int ret = 0;
 516     struct dh_gen_ctx *gctx = genctx;
 517     DH *dh = NULL;
 518     BN_GENCB *gencb = NULL;
 519     FFC_PARAMS *ffc;
 520
 521     if (gctx == NULL)
 522         return NULL;
 523
 524     /* For parameter generation - If there is a group name just create it */
 525     if (gctx->gen_type == DH_PARAMGEN_TYPE_GROUP) {
 526         /* Select a named group if there is not one already */
 527         if (gctx->group_nid == NID_undef)
 528             gctx->group_nid = dh_get_named_group_uid_from_size(gctx->pbits);
 529         if (gctx->group_nid == NID_undef)
 530             return NULL;
 531         dh = dh_new_by_nid_with_libctx(gctx->libctx, gctx->group_nid);
 532         if (dh == NULL)
 533             return NULL;
 534         ffc = dh_get0_params(dh);
 535     } else {
 536         dh = dh_new_with_libctx(gctx->libctx);
 537         if (dh == NULL)
 538             return NULL;
 539         ffc = dh_get0_params(dh);
 540
 541         /* Copy the template value if one was passed */
 542         if (gctx->ffc_params != NULL
 543             && !ffc_params_copy(ffc, gctx->ffc_params))
 544             goto end;
 545
 546         if (!ffc_params_set_seed(ffc, gctx->seed, gctx->seedlen))
 547             goto end;
 548         if (gctx->gindex != -1) {
 549             ffc_params_set_gindex(ffc, gctx->gindex);
 550             if (gctx->pcounter != -1)
 551                 ffc_params_set_pcounter(ffc, gctx->pcounter);
 552         } else if (gctx->hindex != 0) {
 553             ffc_params_set_h(ffc, gctx->hindex);
 554         }
 555         gctx->cb = osslcb;
 556         gctx->cbarg = cbarg;
 557         gencb = BN_GENCB_new();
 558         if (gencb != NULL)
 559             BN_GENCB_set(gencb, dh_gencb, genctx);
 560
 561         if ((gctx->selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0) {
 562             /*
 563              * NOTE: The old safe prime generator code is not used in fips mode,
 564              * (i.e internally it ignores the generator and chooses a named
 565              * group based on pbits.
 566              */
 567             if (gctx->gen_type == DH_PARAMGEN_TYPE_GENERATOR)
 568                 ret = DH_generate_parameters_ex(dh, gctx->pbits,
 569                                                 gctx->generator, gencb);
 570             else
 571                 ret = dh_generate_ffc_parameters(dh, gctx->gen_type, gctx->pbits,
 572                                                  gctx->qbits, gctx->md, gencb);
 573             if (ret <= 0)
 574                 goto end;
 575         }
 576     }
 577
 578     if ((gctx->selection & OSSL_KEYMGMT_SELECT_KEYPAIR) != 0) {
 579         if (ffc->p == NULL || ffc->g == NULL)
 580             goto end;
 581         if (gctx->priv_len > 0)
 582             DH_set_length(dh, (long)gctx->priv_len);
 583         if (DH_generate_key(dh) <= 0)
 584             goto end;
 585     }
 586     ret = 1;
 587 end:
 588     if (ret <= 0) {
 589         DH_free(dh);
 590         dh = NULL;
 591     }
 592     BN_GENCB_free(gencb);
 593     return dh;
 594 }
 595
 596 static void dh_gen_cleanup(void *genctx)
 597 {
 598     struct dh_gen_ctx *gctx = genctx;
 599
 600     if (gctx == NULL)
 601         return;
 602
 603     OPENSSL_clear_free(gctx->seed, gctx->seedlen);
 604     EVP_MD_free(gctx->md);
 605     OPENSSL_free(gctx);
 606 }
 607
 608 const OSSL_DISPATCH dh_keymgmt_functions[] = {
 609     { OSSL_FUNC_KEYMGMT_NEW, (void (*)(void))dh_newdata },
 610     { OSSL_FUNC_KEYMGMT_GEN_INIT, (void (*)(void))dh_gen_init },
 611     { OSSL_FUNC_KEYMGMT_GEN_SET_TEMPLATE, (void (*)(void))dh_gen_set_template },
 612     { OSSL_FUNC_KEYMGMT_GEN_SET_PARAMS, (void (*)(void))dh_gen_set_params },
 613     { OSSL_FUNC_KEYMGMT_GEN_SETTABLE_PARAMS,
 614       (void (*)(void))dh_gen_settable_params },
 615     { OSSL_FUNC_KEYMGMT_GEN, (void (*)(void))dh_gen },
 616     { OSSL_FUNC_KEYMGMT_GEN_CLEANUP, (void (*)(void))dh_gen_cleanup },
 617     { OSSL_FUNC_KEYMGMT_FREE, (void (*)(void))dh_freedata },
 618     { OSSL_FUNC_KEYMGMT_GET_PARAMS, (void (*) (void))dh_get_params },
 619     { OSSL_FUNC_KEYMGMT_GETTABLE_PARAMS, (void (*) (void))dh_gettable_params },
 620     { OSSL_FUNC_KEYMGMT_HAS, (void (*)(void))dh_has },
 621     { OSSL_FUNC_KEYMGMT_MATCH, (void (*)(void))dh_match },
 622     { OSSL_FUNC_KEYMGMT_VALIDATE, (void (*)(void))dh_validate },
 623     { OSSL_FUNC_KEYMGMT_IMPORT, (void (*)(void))dh_import },
 624     { OSSL_FUNC_KEYMGMT_IMPORT_TYPES, (void (*)(void))dh_import_types },
 625     { OSSL_FUNC_KEYMGMT_EXPORT, (void (*)(void))dh_export },
 626     { OSSL_FUNC_KEYMGMT_EXPORT_TYPES, (void (*)(void))dh_export_types },
 627     { 0, NULL }
 628 };