crypto/dh/dh_ameth.c

   1 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
   2  * project 2006.
   3  */
   4 /* ====================================================================
   5  * Copyright (c) 2006 The OpenSSL Project.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  *
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in
  16  *    the documentation and/or other materials provided with the
  17  *    distribution.
  18  *
  19  * 3. All advertising materials mentioning features or use of this
  20  *    software must display the following acknowledgment:
  21  *    "This product includes software developed by the OpenSSL Project
  22  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  23  *
  24  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  25  *    endorse or promote products derived from this software without
  26  *    prior written permission. For written permission, please contact
  27  *    licensing@OpenSSL.org.
  28  *
  29  * 5. Products derived from this software may not be called "OpenSSL"
  30  *    nor may "OpenSSL" appear in their names without prior written
  31  *    permission of the OpenSSL Project.
  32  *
  33  * 6. Redistributions of any form whatsoever must retain the following
  34  *    acknowledgment:
  35  *    "This product includes software developed by the OpenSSL Project
  36  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  37  *
  38  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  39  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  40  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  41  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  42  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  43  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  44  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  45  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  46  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  47  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  48  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  49  * OF THE POSSIBILITY OF SUCH DAMAGE.
  50  * ====================================================================
  51  *
  52  * This product includes cryptographic software written by Eric Young
  53  * (eay@cryptsoft.com).  This product includes software written by Tim
  54  * Hudson (tjh@cryptsoft.com).
  55  *
  56  */
  57
  58 #include <stdio.h>
  59 #include "cryptlib.h"
  60 #include <openssl/x509.h>
  61 #include <openssl/asn1.h>
  62 #include <openssl/dh.h>
  63 #include <openssl/bn.h>
  64 #include "asn1_locl.h"
  65
  66 extern const EVP_PKEY_ASN1_METHOD dhx_asn1_meth;
  67
  68 /* i2d/d2i like DH parameter functions which use the appropriate routine
  69  * for PKCS#3 DH or X9.42 DH.
  70  */
  71
  72 static DH * d2i_dhp(const EVP_PKEY *pkey, const unsigned char **pp, long length)
  73         {
  74         if (pkey->ameth == &dhx_asn1_meth)
  75                 return d2i_DHxparams(NULL, pp, length);
  76         return d2i_DHparams(NULL, pp, length);
  77         }
  78
  79 static int i2d_dhp(const EVP_PKEY *pkey, const DH *a, unsigned char **pp)
  80         {
  81         if (pkey->ameth == &dhx_asn1_meth)
  82                 return i2d_DHxparams(a, pp);
  83         return i2d_DHparams(a, pp);
  84         }
  85
  86 static void int_dh_free(EVP_PKEY *pkey)
  87         {
  88         DH_free(pkey->pkey.dh);
  89         }
  90
  91 static int dh_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
  92         {
  93         const unsigned char *p, *pm;
  94         int pklen, pmlen;
  95         int ptype;
  96         void *pval;
  97         ASN1_STRING *pstr;
  98         X509_ALGOR *palg;
  99         ASN1_INTEGER *public_key = NULL;
 100
 101         DH *dh = NULL;
 102
 103         if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
 104                 return 0;
 105         X509_ALGOR_get0(NULL, &ptype, &pval, palg);
 106
 107         if (ptype != V_ASN1_SEQUENCE)
 108                 {
 109                 DHerr(DH_F_DH_PUB_DECODE, DH_R_PARAMETER_ENCODING_ERROR);
 110                 goto err;
 111                 }
 112
 113         pstr = pval;
 114         pm = pstr->data;
 115         pmlen = pstr->length;
 116
 117         if (!(dh = d2i_dhp(pkey, &pm, pmlen)))
 118                 {
 119                 DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
 120                 goto err;
 121                 }
 122
 123         if (!(public_key=d2i_ASN1_INTEGER(NULL, &p, pklen)))
 124                 {
 125                 DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
 126                 goto err;
 127                 }
 128
 129         /* We have parameters now set public key */
 130         if (!(dh->pub_key = ASN1_INTEGER_to_BN(public_key, NULL)))
 131                 {
 132                 DHerr(DH_F_DH_PUB_DECODE, DH_R_BN_DECODE_ERROR);
 133                 goto err;
 134                 }
 135
 136         ASN1_INTEGER_free(public_key);
 137         EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, dh);
 138         return 1;
 139
 140         err:
 141         if (public_key)
 142                 ASN1_INTEGER_free(public_key);
 143         if (dh)
 144                 DH_free(dh);
 145         return 0;
 146
 147         }
 148
 149 static int dh_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
 150         {
 151         DH *dh;
 152         void *pval = NULL;
 153         int ptype;
 154         unsigned char *penc = NULL;
 155         int penclen;
 156         ASN1_STRING *str;
 157         ASN1_INTEGER *pub_key = NULL;
 158
 159         dh=pkey->pkey.dh;
 160
 161         str = ASN1_STRING_new();
 162         str->length = i2d_dhp(pkey, dh, &str->data);
 163         if (str->length <= 0)
 164                 {
 165                 DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
 166                 goto err;
 167                 }
 168         pval = str;
 169         ptype = V_ASN1_SEQUENCE;
 170
 171         pub_key = BN_to_ASN1_INTEGER(dh->pub_key, NULL);
 172         if (!pub_key)
 173                 goto err;
 174
 175         penclen = i2d_ASN1_INTEGER(pub_key, &penc);
 176
 177         ASN1_INTEGER_free(pub_key);
 178
 179         if (penclen <= 0)
 180                 {
 181                 DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
 182                 goto err;
 183                 }
 184
 185         if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(pkey->ameth->pkey_id),
 186                                 ptype, pval, penc, penclen))
 187                 return 1;
 188
 189         err:
 190         if (penc)
 191                 OPENSSL_free(penc);
 192         if (pval)
 193                 ASN1_STRING_free(pval);
 194
 195         return 0;
 196         }
 197
 198
 199 /* PKCS#8 DH is defined in PKCS#11 of all places. It is similar to DH in
 200  * that the AlgorithmIdentifier contains the paramaters, the private key
 201  * is explcitly included and the pubkey must be recalculated.
 202  */
 203
 204 static int dh_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
 205         {
 206         const unsigned char *p, *pm;
 207         int pklen, pmlen;
 208         int ptype;
 209         void *pval;
 210         ASN1_STRING *pstr;
 211         X509_ALGOR *palg;
 212         ASN1_INTEGER *privkey = NULL;
 213
 214         DH *dh = NULL;
 215
 216         if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
 217                 return 0;
 218
 219         X509_ALGOR_get0(NULL, &ptype, &pval, palg);
 220
 221         if (ptype != V_ASN1_SEQUENCE)
 222                         goto decerr;
 223
 224         if (!(privkey=d2i_ASN1_INTEGER(NULL, &p, pklen)))
 225                 goto decerr;
 226
 227
 228         pstr = pval;
 229         pm = pstr->data;
 230         pmlen = pstr->length;
 231         if (!(dh = d2i_dhp(pkey, &pm, pmlen)))
 232                 goto decerr;
 233         /* We have parameters now set private key */
 234         if (!(dh->priv_key = ASN1_INTEGER_to_BN(privkey, NULL)))
 235                 {
 236                 DHerr(DH_F_DH_PRIV_DECODE,DH_R_BN_ERROR);
 237                 goto dherr;
 238                 }
 239         /* Calculate public key */
 240         if (!DH_generate_key(dh))
 241                 goto dherr;
 242
 243         EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, dh);
 244
 245         ASN1_INTEGER_free(privkey);
 246
 247         return 1;
 248
 249         decerr:
 250         DHerr(DH_F_DH_PRIV_DECODE, EVP_R_DECODE_ERROR);
 251         dherr:
 252         DH_free(dh);
 253         return 0;
 254         }
 255
 256 static int dh_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
 257 {
 258         ASN1_STRING *params = NULL;
 259         ASN1_INTEGER *prkey = NULL;
 260         unsigned char *dp = NULL;
 261         int dplen;
 262
 263         params = ASN1_STRING_new();
 264
 265         if (!params)
 266                 {
 267                 DHerr(DH_F_DH_PRIV_ENCODE,ERR_R_MALLOC_FAILURE);
 268                 goto err;
 269                 }
 270
 271         params->length = i2d_dhp(pkey, pkey->pkey.dh, &params->data);
 272         if (params->length <= 0)
 273                 {
 274                 DHerr(DH_F_DH_PRIV_ENCODE,ERR_R_MALLOC_FAILURE);
 275                 goto err;
 276                 }
 277         params->type = V_ASN1_SEQUENCE;
 278
 279         /* Get private key into integer */
 280         prkey = BN_to_ASN1_INTEGER(pkey->pkey.dh->priv_key, NULL);
 281
 282         if (!prkey)
 283                 {
 284                 DHerr(DH_F_DH_PRIV_ENCODE,DH_R_BN_ERROR);
 285                 goto err;
 286                 }
 287
 288         dplen = i2d_ASN1_INTEGER(prkey, &dp);
 289
 290         ASN1_INTEGER_free(prkey);
 291
 292         if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(pkey->ameth->pkey_id), 0,
 293                                 V_ASN1_SEQUENCE, params, dp, dplen))
 294                 goto err;
 295
 296         return 1;
 297
 298 err:
 299         if (dp != NULL)
 300                 OPENSSL_free(dp);
 301         if (params != NULL)
 302                 ASN1_STRING_free(params);
 303         if (prkey != NULL)
 304                 ASN1_INTEGER_free(prkey);
 305         return 0;
 306 }
 307
 308
 309 static void update_buflen(const BIGNUM *b, size_t *pbuflen)
 310         {
 311         size_t i;
 312         if (!b)
 313                 return;
 314         if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
 315                         *pbuflen = i;
 316         }
 317
 318 static int dh_param_decode(EVP_PKEY *pkey,
 319                                         const unsigned char **pder, int derlen)
 320         {
 321         DH *dh;
 322         if (!(dh = d2i_dhp(pkey, pder, derlen)))
 323                 {
 324                 DHerr(DH_F_DH_PARAM_DECODE, ERR_R_DH_LIB);
 325                 return 0;
 326                 }
 327         EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, dh);
 328         return 1;
 329         }
 330
 331 static int dh_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
 332         {
 333         return i2d_dhp(pkey, pkey->pkey.dh, pder);
 334         }
 335
 336 static int do_dh_print(BIO *bp, const DH *x, int indent,
 337                                                 ASN1_PCTX *ctx, int ptype)
 338         {
 339         unsigned char *m=NULL;
 340         int reason=ERR_R_BUF_LIB,ret=0;
 341         size_t buf_len=0;
 342
 343         const char *ktype = NULL;
 344
 345         BIGNUM *priv_key, *pub_key;
 346
 347         if (ptype == 2)
 348                 priv_key = x->priv_key;
 349         else
 350                 priv_key = NULL;
 351
 352         if (ptype > 0)
 353                 pub_key = x->pub_key;
 354         else
 355                 pub_key = NULL;
 356
 357         update_buflen(x->p, &buf_len);
 358
 359         if (buf_len == 0)
 360                 {
 361                 reason = ERR_R_PASSED_NULL_PARAMETER;
 362                 goto err;
 363                 }
 364
 365         update_buflen(x->g, &buf_len);
 366         update_buflen(x->q, &buf_len);
 367         update_buflen(pub_key, &buf_len);
 368         update_buflen(priv_key, &buf_len);
 369
 370         if (ptype == 2)
 371                 ktype = "DH Private-Key";
 372         else if (ptype == 1)
 373                 ktype = "DH Public-Key";
 374         else
 375                 ktype = "DH Parameters";
 376
 377         m= OPENSSL_malloc(buf_len+10);
 378         if (m == NULL)
 379                 {
 380                 reason=ERR_R_MALLOC_FAILURE;
 381                 goto err;
 382                 }
 383
 384         BIO_indent(bp, indent, 128);
 385         if (BIO_printf(bp,"%s: (%d bit)\n", ktype, BN_num_bits(x->p)) <= 0)
 386                 goto err;
 387         indent += 4;
 388
 389         if (!ASN1_bn_print(bp,"private-key:",priv_key,m,indent)) goto err;
 390         if (!ASN1_bn_print(bp,"public-key:",pub_key,m,indent)) goto err;
 391
 392         if (!ASN1_bn_print(bp,"prime:",x->p,m,indent)) goto err;
 393         if (!ASN1_bn_print(bp,"generator:",x->g,m,indent)) goto err;
 394         if (x->q && !ASN1_bn_print(bp,"subgroup order:",x->q,m,indent)) goto err;
 395         if (x->length != 0)
 396                 {
 397                 BIO_indent(bp, indent, 128);
 398                 if (BIO_printf(bp,"recommended-private-length: %d bits\n",
 399                         (int)x->length) <= 0) goto err;
 400                 }
 401
 402
 403         ret=1;
 404         if (0)
 405                 {
 406 err:
 407                 DHerr(DH_F_DO_DH_PRINT,reason);
 408                 }
 409         if (m != NULL) OPENSSL_free(m);
 410         return(ret);
 411         }
 412
 413 static int int_dh_size(const EVP_PKEY *pkey)
 414         {
 415         return(DH_size(pkey->pkey.dh));
 416         }
 417
 418 static int dh_bits(const EVP_PKEY *pkey)
 419         {
 420         return BN_num_bits(pkey->pkey.dh->p);
 421         }
 422
 423 static int dh_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
 424         {
 425         if (    BN_cmp(a->pkey.dh->p,b->pkey.dh->p) ||
 426                 BN_cmp(a->pkey.dh->g,b->pkey.dh->g))
 427                 return 0;
 428         else if (a->ameth == &dhx_asn1_meth)
 429                 {
 430                 if (BN_cmp(a->pkey.dh->q,b->pkey.dh->q))
 431                         return 0;
 432                 }
 433         return 1;
 434         }
 435
 436 static int dh_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
 437         {
 438         BIGNUM *a;
 439
 440         if ((a=BN_dup(from->pkey.dh->p)) == NULL)
 441                 return 0;
 442         if (to->pkey.dh->p != NULL)
 443                 BN_free(to->pkey.dh->p);
 444         to->pkey.dh->p=a;
 445
 446         if ((a=BN_dup(from->pkey.dh->g)) == NULL)
 447                 return 0;
 448         if (to->pkey.dh->g != NULL)
 449                 BN_free(to->pkey.dh->g);
 450         to->pkey.dh->g=a;
 451         if (from->ameth == &dhx_asn1_meth)
 452                 {
 453                 a = BN_dup(from->pkey.dh->q);
 454                 if (!a)
 455                         return 0;
 456                 if (to->pkey.dh->q)
 457                         BN_free(to->pkey.dh->q);
 458                 to->pkey.dh->q = a;
 459                 }
 460
 461         return 1;
 462         }
 463
 464 static int dh_missing_parameters(const EVP_PKEY *a)
 465         {
 466         if (!a->pkey.dh->p || !a->pkey.dh->g)
 467                 return 1;
 468         return 0;
 469         }
 470
 471 static int dh_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
 472         {
 473         if (dh_cmp_parameters(a, b) == 0)
 474                 return 0;
 475         if (BN_cmp(b->pkey.dh->pub_key,a->pkey.dh->pub_key) != 0)
 476                 return 0;
 477         else
 478                 return 1;
 479         }
 480
 481 static int dh_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 482                                                         ASN1_PCTX *ctx)
 483         {
 484         return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 0);
 485         }
 486
 487 static int dh_public_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 488                                                         ASN1_PCTX *ctx)
 489         {
 490         return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 1);
 491         }
 492
 493 static int dh_private_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 494                                                         ASN1_PCTX *ctx)
 495         {
 496         return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 2);
 497         }
 498
 499 int DHparams_print(BIO *bp, const DH *x)
 500         {
 501         return do_dh_print(bp, x, 4, NULL, 0);
 502         }
 503
 504 const EVP_PKEY_ASN1_METHOD dh_asn1_meth =
 505         {
 506         EVP_PKEY_DH,
 507         EVP_PKEY_DH,
 508         0,
 509
 510         "DH",
 511         "OpenSSL PKCS#3 DH method",
 512
 513         dh_pub_decode,
 514         dh_pub_encode,
 515         dh_pub_cmp,
 516         dh_public_print,
 517
 518         dh_priv_decode,
 519         dh_priv_encode,
 520         dh_private_print,
 521
 522         int_dh_size,
 523         dh_bits,
 524
 525         dh_param_decode,
 526         dh_param_encode,
 527         dh_missing_parameters,
 528         dh_copy_parameters,
 529         dh_cmp_parameters,
 530         dh_param_print,
 531         0,
 532
 533         int_dh_free,
 534         0
 535         };
 536
 537 const EVP_PKEY_ASN1_METHOD dhx_asn1_meth =
 538         {
 539         EVP_PKEY_DHX,
 540         EVP_PKEY_DHX,
 541         0,
 542
 543         "X9.42 DH",
 544         "OpenSSL X9.42 DH method",
 545
 546         dh_pub_decode,
 547         dh_pub_encode,
 548         dh_pub_cmp,
 549         dh_public_print,
 550
 551         dh_priv_decode,
 552         dh_priv_encode,
 553         dh_private_print,
 554
 555         int_dh_size,
 556         dh_bits,
 557
 558         dh_param_decode,
 559         dh_param_encode,
 560         dh_missing_parameters,
 561         dh_copy_parameters,
 562         dh_cmp_parameters,
 563         dh_param_print,
 564         0,
 565
 566         int_dh_free,
 567         0
 568         };
 569