crypto/evp/pmeth_gn.c

   1 /*
   2  * Copyright 2006-2020 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 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <openssl/core.h>
  13 #include <openssl/core_names.h>
  14 #include "internal/cryptlib.h"
  15 #include "internal/core.h"
  16 #include <openssl/objects.h>
  17 #include <openssl/evp.h>
  18 #include "crypto/bn.h"
  19 #include "crypto/asn1.h"
  20 #include "crypto/evp.h"
  21 #include "evp_local.h"
  22
  23 #if !defined(FIPS_MODULE) && !defined(OPENSSL_NO_EC)
  24 # define TMP_SM2_HACK
  25 #endif
  26
  27 /* TODO(3.0) remove when provider SM2 key generation is implemented */
  28 #ifdef TMP_SM2_HACK
  29 # include <openssl/ec.h>
  30 # include <openssl/serializer.h>
  31 # include "internal/sizes.h"
  32 #endif
  33
  34 static int gen_init(EVP_PKEY_CTX *ctx, int operation)
  35 {
  36     int ret = 0;
  37
  38     if (ctx == NULL)
  39         goto not_supported;
  40
  41     evp_pkey_ctx_free_old_ops(ctx);
  42     ctx->operation = operation;
  43
  44     if (ctx->keymgmt == NULL || ctx->keymgmt->gen_init == NULL)
  45         goto legacy;
  46
  47 /* TODO remove when provider SM2 key generation is implemented */
  48 #ifdef TMP_SM2_HACK
  49     if (ctx->pmeth != NULL && ctx->pmeth->pkey_id == EVP_PKEY_SM2)
  50         goto legacy;
  51 #endif
  52
  53     switch (operation) {
  54     case EVP_PKEY_OP_PARAMGEN:
  55         ctx->op.keymgmt.genctx =
  56             evp_keymgmt_gen_init(ctx->keymgmt,
  57                                  OSSL_KEYMGMT_SELECT_ALL_PARAMETERS);
  58         break;
  59     case EVP_PKEY_OP_KEYGEN:
  60         ctx->op.keymgmt.genctx =
  61             evp_keymgmt_gen_init(ctx->keymgmt, OSSL_KEYMGMT_SELECT_KEYPAIR);
  62         break;
  63     }
  64
  65     if (ctx->op.keymgmt.genctx == NULL)
  66         ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
  67     else
  68         ret = 1;
  69     goto end;
  70
  71  legacy:
  72 #ifdef FIPS_MODULE
  73     goto not_supported;
  74 #else
  75     if (ctx->pmeth == NULL
  76         || (operation == EVP_PKEY_OP_PARAMGEN
  77             && ctx->pmeth->paramgen == NULL)
  78         || (operation == EVP_PKEY_OP_KEYGEN
  79             && ctx->pmeth->keygen == NULL))
  80         goto not_supported;
  81
  82     ret = 1;
  83     switch (operation) {
  84     case EVP_PKEY_OP_PARAMGEN:
  85         if (ctx->pmeth->paramgen_init != NULL)
  86             ret = ctx->pmeth->paramgen_init(ctx);
  87         break;
  88     case EVP_PKEY_OP_KEYGEN:
  89         if (ctx->pmeth->keygen_init != NULL)
  90             ret = ctx->pmeth->keygen_init(ctx);
  91         break;
  92     }
  93 #endif
  94
  95  end:
  96     if (ret <= 0)
  97         ctx->operation = EVP_PKEY_OP_UNDEFINED;
  98     return ret;
  99
 100  not_supported:
 101     ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
 102     ret = -2;
 103     goto end;
 104 }
 105
 106 int EVP_PKEY_paramgen_init(EVP_PKEY_CTX *ctx)
 107 {
 108     return gen_init(ctx, EVP_PKEY_OP_PARAMGEN);
 109 }
 110
 111 int EVP_PKEY_keygen_init(EVP_PKEY_CTX *ctx)
 112 {
 113     return gen_init(ctx, EVP_PKEY_OP_KEYGEN);
 114 }
 115
 116 static int ossl_callback_to_pkey_gencb(const OSSL_PARAM params[], void *arg)
 117 {
 118     EVP_PKEY_CTX *ctx = arg;
 119     const OSSL_PARAM *param = NULL;
 120     int p = -1, n = -1;
 121
 122     if (ctx->pkey_gencb == NULL)
 123         return 1;                /* No callback?  That's fine */
 124
 125     if ((param = OSSL_PARAM_locate_const(params, OSSL_GEN_PARAM_POTENTIAL))
 126         == NULL
 127         || !OSSL_PARAM_get_int(param, &p))
 128         return 0;
 129     if ((param = OSSL_PARAM_locate_const(params, OSSL_GEN_PARAM_ITERATION))
 130         == NULL
 131         || !OSSL_PARAM_get_int(param, &n))
 132         return 0;
 133
 134     ctx->keygen_info[0] = p;
 135     ctx->keygen_info[1] = n;
 136
 137     return ctx->pkey_gencb(ctx);
 138 }
 139
 140 int EVP_PKEY_gen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)
 141 {
 142     int ret = 0;
 143     OSSL_CALLBACK cb;
 144     EVP_PKEY *allocated_pkey = NULL;
 145
 146     if (ppkey == NULL)
 147         return -1;
 148
 149     if (ctx == NULL)
 150         goto not_supported;
 151
 152     if ((ctx->operation & EVP_PKEY_OP_TYPE_GEN) == 0)
 153         goto not_initialized;
 154
 155     if (*ppkey == NULL)
 156         *ppkey = allocated_pkey = EVP_PKEY_new();
 157
 158     if (*ppkey == NULL) {
 159         ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
 160         return -1;
 161     }
 162
 163     if (ctx->op.keymgmt.genctx == NULL)
 164         goto legacy;
 165
 166     ret = 1;
 167     if (ctx->pkey != NULL) {
 168         EVP_KEYMGMT *tmp_keymgmt = ctx->keymgmt;
 169         void *keydata =
 170             evp_pkey_export_to_provider(ctx->pkey, ctx->libctx,
 171                                         &tmp_keymgmt, ctx->propquery);
 172
 173         if (tmp_keymgmt == NULL)
 174             goto not_supported;
 175         /*
 176          * It's ok if keydata is NULL here.  The backend is expected to deal
 177          * with that as it sees fit.
 178          */
 179         ret = evp_keymgmt_gen_set_template(ctx->keymgmt,
 180                                            ctx->op.keymgmt.genctx, keydata);
 181     }
 182
 183     /*
 184      * the returned value from evp_keymgmt_util_gen() is cached in *ppkey,
 185      * so we so not need to save it, just check it.
 186      */
 187     ret = ret
 188         && (evp_keymgmt_util_gen(*ppkey, ctx->keymgmt, ctx->op.keymgmt.genctx,
 189                                  ossl_callback_to_pkey_gencb, ctx)
 190             != NULL);
 191
 192 #ifndef FIPS_MODULE
 193     /* In case |*ppkey| was originally a legacy key */
 194     if (ret)
 195         evp_pkey_free_legacy(*ppkey);
 196 #endif
 197
 198 /* TODO remove when SM2 key have been cleanly separated from EC keys */
 199 #ifdef TMP_SM2_HACK
 200     /*
 201      * Legacy SM2 keys are implemented as EC_KEY with a twist.  The legacy
 202      * key generation detects the SM2 curve and "magically" changes the pkey
 203      * id accordingly.
 204      * Since we don't have SM2 in the provider implementation, we need to
 205      * downgrade the generated provider side key to a legacy one under the
 206      * same conditions.
 207      *
 208      * THIS IS AN UGLY BUT TEMPORARY HACK
 209      */
 210     {
 211         char curve_name[OSSL_MAX_NAME_SIZE] = "";
 212
 213         if (EVP_PKEY_CTX_get_ec_paramgen_curve_name(ctx, curve_name,
 214                                                     sizeof(curve_name)) < 1
 215             || strcmp(curve_name, "SM2") != 0)
 216             goto end;
 217     }
 218
 219     if (!evp_pkey_downgrade(*ppkey)
 220         || !EVP_PKEY_set_alias_type(*ppkey, EVP_PKEY_SM2))
 221         ret = 0;
 222 #endif
 223     goto end;
 224
 225  legacy:
 226 #ifdef FIPS_MODULE
 227     goto not_supported;
 228 #else
 229     if (ctx->pkey && !evp_pkey_downgrade(ctx->pkey))
 230         goto not_accessible;
 231     switch (ctx->operation) {
 232     case EVP_PKEY_OP_PARAMGEN:
 233         ret = ctx->pmeth->paramgen(ctx, *ppkey);
 234         break;
 235     case EVP_PKEY_OP_KEYGEN:
 236         ret = ctx->pmeth->keygen(ctx, *ppkey);
 237         break;
 238     default:
 239         goto not_supported;
 240     }
 241 #endif
 242
 243  end:
 244     if (ret <= 0) {
 245         if (allocated_pkey != NULL)
 246             *ppkey = NULL;
 247         EVP_PKEY_free(allocated_pkey);
 248     }
 249     return ret;
 250
 251  not_supported:
 252     ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
 253     ret = -2;
 254     goto end;
 255  not_initialized:
 256     ERR_raise(ERR_LIB_EVP, EVP_R_OPERATON_NOT_INITIALIZED);
 257     ret = -1;
 258     goto end;
 259 #ifndef FIPS_MODULE
 260  not_accessible:
 261     ERR_raise(ERR_LIB_EVP, EVP_R_INACCESSIBLE_DOMAIN_PARAMETERS);
 262     ret = -1;
 263     goto end;
 264 #endif
 265 }
 266
 267 int EVP_PKEY_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)
 268 {
 269     if (ctx->operation != EVP_PKEY_OP_PARAMGEN) {
 270         ERR_raise(ERR_LIB_EVP, EVP_R_OPERATON_NOT_INITIALIZED);
 271         return -1;
 272     }
 273     return EVP_PKEY_gen(ctx, ppkey);
 274 }
 275
 276 int EVP_PKEY_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey)
 277 {
 278     if (ctx->operation != EVP_PKEY_OP_KEYGEN) {
 279         ERR_raise(ERR_LIB_EVP, EVP_R_OPERATON_NOT_INITIALIZED);
 280         return -1;
 281     }
 282     return EVP_PKEY_gen(ctx, ppkey);
 283 }
 284
 285 void EVP_PKEY_CTX_set_cb(EVP_PKEY_CTX *ctx, EVP_PKEY_gen_cb *cb)
 286 {
 287     ctx->pkey_gencb = cb;
 288 }
 289
 290 EVP_PKEY_gen_cb *EVP_PKEY_CTX_get_cb(EVP_PKEY_CTX *ctx)
 291 {
 292     return ctx->pkey_gencb;
 293 }
 294
 295 /*
 296  * "translation callback" to call EVP_PKEY_CTX callbacks using BN_GENCB style
 297  * callbacks.
 298  */
 299
 300 static int trans_cb(int a, int b, BN_GENCB *gcb)
 301 {
 302     EVP_PKEY_CTX *ctx = BN_GENCB_get_arg(gcb);
 303     ctx->keygen_info[0] = a;
 304     ctx->keygen_info[1] = b;
 305     return ctx->pkey_gencb(ctx);
 306 }
 307
 308 void evp_pkey_set_cb_translate(BN_GENCB *cb, EVP_PKEY_CTX *ctx)
 309 {
 310     BN_GENCB_set(cb, trans_cb, ctx);
 311 }
 312
 313 int EVP_PKEY_CTX_get_keygen_info(EVP_PKEY_CTX *ctx, int idx)
 314 {
 315     if (idx == -1)
 316         return ctx->keygen_info_count;
 317     if (idx < 0 || idx > ctx->keygen_info_count)
 318         return 0;
 319     return ctx->keygen_info[idx];
 320 }
 321
 322 #ifndef FIPS_MODULE
 323
 324 EVP_PKEY *EVP_PKEY_new_mac_key(int type, ENGINE *e,
 325                                const unsigned char *key, int keylen)
 326 {
 327     EVP_PKEY_CTX *mac_ctx = NULL;
 328     EVP_PKEY *mac_key = NULL;
 329     mac_ctx = EVP_PKEY_CTX_new_id(type, e);
 330     if (!mac_ctx)
 331         return NULL;
 332     if (EVP_PKEY_keygen_init(mac_ctx) <= 0)
 333         goto merr;
 334     if (EVP_PKEY_CTX_set_mac_key(mac_ctx, key, keylen) <= 0)
 335         goto merr;
 336     if (EVP_PKEY_keygen(mac_ctx, &mac_key) <= 0)
 337         goto merr;
 338  merr:
 339     EVP_PKEY_CTX_free(mac_ctx);
 340     return mac_key;
 341 }
 342
 343 #endif /* FIPS_MODULE */
 344
 345 /*- All methods below can also be used in FIPS_MODULE */
 346
 347 static int fromdata_init(EVP_PKEY_CTX *ctx, int operation)
 348 {
 349     if (ctx == NULL || ctx->keytype == NULL)
 350         goto not_supported;
 351
 352     evp_pkey_ctx_free_old_ops(ctx);
 353     if (ctx->keymgmt == NULL)
 354         goto not_supported;
 355
 356     ctx->operation = operation;
 357     return 1;
 358
 359  not_supported:
 360     ctx->operation = EVP_PKEY_OP_UNDEFINED;
 361     ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
 362     return -2;
 363 }
 364
 365 int EVP_PKEY_param_fromdata_init(EVP_PKEY_CTX *ctx)
 366 {
 367     return fromdata_init(ctx, EVP_PKEY_OP_PARAMFROMDATA);
 368 }
 369
 370 int EVP_PKEY_key_fromdata_init(EVP_PKEY_CTX *ctx)
 371 {
 372     return fromdata_init(ctx, EVP_PKEY_OP_KEYFROMDATA);
 373 }
 374
 375 int EVP_PKEY_fromdata(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey, OSSL_PARAM params[])
 376 {
 377     void *keydata = NULL;
 378     int selection;
 379
 380     if (ctx == NULL || (ctx->operation & EVP_PKEY_OP_TYPE_FROMDATA) == 0) {
 381         ERR_raise(ERR_LIB_EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
 382         return -2;
 383     }
 384
 385     if (ppkey == NULL)
 386         return -1;
 387
 388     if (*ppkey == NULL)
 389         *ppkey = EVP_PKEY_new();
 390
 391     if (*ppkey == NULL) {
 392         ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
 393         return -1;
 394     }
 395
 396     if (ctx->operation == EVP_PKEY_OP_PARAMFROMDATA)
 397         selection = OSSL_KEYMGMT_SELECT_ALL_PARAMETERS;
 398     else
 399         selection = OSSL_KEYMGMT_SELECT_ALL;
 400     keydata = evp_keymgmt_util_fromdata(*ppkey, ctx->keymgmt, selection,
 401                                         params);
 402
 403     if (keydata == NULL)
 404         return 0;
 405     /* keydata is cached in *ppkey, so we need not bother with it further */
 406     return 1;
 407 }
 408
 409 /*
 410  * TODO(3.0) Re-evaluate the names, it's possible that we find these to be
 411  * better:
 412  *
 413  * EVP_PKEY_param_settable()
 414  * EVP_PKEY_param_gettable()
 415  */
 416 const OSSL_PARAM *EVP_PKEY_param_fromdata_settable(EVP_PKEY_CTX *ctx)
 417 {
 418     /* We call fromdata_init to get ctx->keymgmt populated */
 419     if (fromdata_init(ctx, EVP_PKEY_OP_UNDEFINED))
 420         return evp_keymgmt_import_types(ctx->keymgmt,
 421                                         OSSL_KEYMGMT_SELECT_ALL_PARAMETERS);
 422     return NULL;
 423 }
 424
 425 const OSSL_PARAM *EVP_PKEY_key_fromdata_settable(EVP_PKEY_CTX *ctx)
 426 {
 427     /* We call fromdata_init to get ctx->keymgmt populated */
 428     if (fromdata_init(ctx, EVP_PKEY_OP_UNDEFINED))
 429         return evp_keymgmt_import_types(ctx->keymgmt,
 430                                         OSSL_KEYMGMT_SELECT_ALL);
 431     return NULL;
 432 }