crypto/dh/dh_ameth.c

   1 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) 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 "asn1_locl.h"
  64
  65 static void int_dh_free(EVP_PKEY *pkey)
  66         {
  67         DH_free(pkey->pkey.dh);
  68         }
  69
  70 static int dh_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
  71         {
  72         const unsigned char *p, *pm;
  73         int pklen, pmlen;
  74         int ptype;
  75         void *pval;
  76         ASN1_STRING *pstr;
  77         X509_ALGOR *palg;
  78         ASN1_INTEGER *public_key = NULL;
  79
  80         DH *dh = NULL;
  81
  82         if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey))
  83                 return 0;
  84         X509_ALGOR_get0(NULL, &ptype, &pval, palg);
  85
  86         if (ptype != V_ASN1_SEQUENCE)
  87                 {
  88                 DHerr(DH_F_DH_PUB_DECODE, DH_R_PARAMETER_ENCODING_ERROR);
  89                 goto err;
  90                 }
  91
  92         pstr = pval;
  93         pm = pstr->data;
  94         pmlen = pstr->length;
  95
  96         if (!(dh = d2i_DHparams(NULL, &pm, pmlen)))
  97                 {
  98                 DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
  99                 goto err;
 100                 }
 101
 102         if (!(public_key=d2i_ASN1_INTEGER(NULL, &p, pklen)))
 103                 {
 104                 DHerr(DH_F_DH_PUB_DECODE, DH_R_DECODE_ERROR);
 105                 goto err;
 106                 }
 107
 108         /* We have parameters now set public key */
 109         if (!(dh->pub_key = ASN1_INTEGER_to_BN(public_key, NULL)))
 110                 {
 111                 DHerr(DH_F_DH_PUB_DECODE, DH_R_BN_DECODE_ERROR);
 112                 goto err;
 113                 }
 114
 115         ASN1_INTEGER_free(public_key);
 116         EVP_PKEY_assign_DH(pkey, dh);
 117         return 1;
 118
 119         err:
 120         if (pubkey)
 121                 ASN1_INTEGER_free(public_key);
 122         if (dh)
 123                 DH_free(dh);
 124         return 0;
 125
 126         }
 127
 128 static int dh_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
 129         {
 130         DH *dh;
 131         void *pval = NULL;
 132         int ptype;
 133         unsigned char *penc = NULL;
 134         int penclen;
 135         ASN1_STRING *str;
 136         ASN1_INTEGER *pub_key = NULL;
 137
 138         dh=pkey->pkey.dh;
 139
 140         str = ASN1_STRING_new();
 141         str->length = i2d_DHparams(dh, &str->data);
 142         if (str->length <= 0)
 143                 {
 144                 DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
 145                 goto err;
 146                 }
 147         pval = str;
 148         ptype = V_ASN1_SEQUENCE;
 149
 150         pub_key = BN_to_ASN1_INTEGER(dh->pub_key, NULL);
 151         if (!pub_key)
 152                 goto err;
 153
 154         penclen = i2d_ASN1_INTEGER(pub_key, &penc);
 155
 156         ASN1_INTEGER_free(pub_key);
 157
 158         if (penclen <= 0)
 159                 {
 160                 DHerr(DH_F_DH_PUB_ENCODE, ERR_R_MALLOC_FAILURE);
 161                 goto err;
 162                 }
 163
 164         if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_DH),
 165                                 ptype, pval, penc, penclen))
 166                 return 1;
 167
 168         err:
 169         if (penc)
 170                 OPENSSL_free(penc);
 171         if (pval)
 172                 ASN1_STRING_free(pval);
 173
 174         return 0;
 175         }
 176
 177
 178 /* PKCS#8 DH is defined in PKCS#11 of all places. It is similar to DH in
 179  * that the AlgorithmIdentifier contains the paramaters, the private key
 180  * is explcitly included and the pubkey must be recalculated.
 181  */
 182
 183 static int dh_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8)
 184         {
 185         const unsigned char *p, *pm;
 186         int pklen, pmlen;
 187         int ptype;
 188         void *pval;
 189         ASN1_STRING *pstr;
 190         X509_ALGOR *palg;
 191         ASN1_INTEGER *privkey = NULL;
 192
 193         DH *dh = NULL;
 194
 195         if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8))
 196                 return 0;
 197
 198         X509_ALGOR_get0(NULL, &ptype, &pval, palg);
 199
 200         if (ptype != V_ASN1_SEQUENCE)
 201                         goto decerr;
 202
 203         if (!(privkey=d2i_ASN1_INTEGER(NULL, &p, pklen)))
 204                 goto decerr;
 205
 206
 207         pstr = pval;
 208         pm = pstr->data;
 209         pmlen = pstr->length;
 210         if (!(dh = d2i_DHparams(NULL, &pm, pmlen)))
 211                 goto decerr;
 212         /* We have parameters now set private key */
 213         if (!(dh->priv_key = ASN1_INTEGER_to_BN(privkey, NULL)))
 214                 {
 215                 DHerr(DH_F_DH_PRIV_DECODE,DH_R_BN_ERROR);
 216                 goto dherr;
 217                 }
 218         /* Calculate public key */
 219         if (!DH_generate_key(dh))
 220                 goto dherr;
 221
 222         EVP_PKEY_assign_DH(pkey, dh);
 223
 224         ASN1_INTEGER_free(privkey);
 225
 226         return 1;
 227
 228         decerr:
 229         DHerr(DH_F_DH_PRIV_DECODE, EVP_R_DECODE_ERROR);
 230         dherr:
 231         DH_free(dh);
 232         return 0;
 233         }
 234
 235 static int dh_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey)
 236 {
 237         ASN1_STRING *params = NULL;
 238         ASN1_INTEGER *prkey = NULL;
 239         unsigned char *dp = NULL;
 240         int dplen;
 241
 242         params = ASN1_STRING_new();
 243
 244         if (!params)
 245                 {
 246                 DHerr(DH_F_DH_PRIV_ENCODE,ERR_R_MALLOC_FAILURE);
 247                 goto err;
 248                 }
 249
 250         params->length = i2d_DHparams(pkey->pkey.dh, &params->data);
 251         if (params->length <= 0)
 252                 {
 253                 DHerr(DH_F_DH_PRIV_ENCODE,ERR_R_MALLOC_FAILURE);
 254                 goto err;
 255                 }
 256         params->type = V_ASN1_SEQUENCE;
 257
 258         /* Get private key into integer */
 259         prkey = BN_to_ASN1_INTEGER(pkey->pkey.dh->priv_key, NULL);
 260
 261         if (!prkey)
 262                 {
 263                 DHerr(DH_F_DH_PRIV_ENCODE,DH_R_BN_ERROR);
 264                 goto err;
 265                 }
 266
 267         dplen = i2d_ASN1_INTEGER(prkey, &dp);
 268
 269         ASN1_INTEGER_free(prkey);
 270
 271         if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_dhKeyAgreement), 0,
 272                                 V_ASN1_SEQUENCE, params, dp, dplen))
 273                 goto err;
 274
 275         return 1;
 276
 277 err:
 278         if (dp != NULL)
 279                 OPENSSL_free(dp);
 280         if (params != NULL)
 281                 ASN1_STRING_free(params);
 282         if (prkey != NULL)
 283                 ASN1_INTEGER_free(prkey);
 284         return 0;
 285 }
 286
 287
 288 static void update_buflen(const BIGNUM *b, size_t *pbuflen)
 289         {
 290         size_t i;
 291         if (!b)
 292                 return;
 293         if (*pbuflen < (i = (size_t)BN_num_bytes(b)))
 294                         *pbuflen = i;
 295         }
 296
 297 static int dh_param_decode(EVP_PKEY *pkey,
 298                                         const unsigned char **pder, int derlen)
 299         {
 300         DH *dh;
 301         if (!(dh = d2i_DHparams(NULL, pder, derlen)))
 302                 {
 303                 DHerr(DH_F_DH_PARAM_DECODE, ERR_R_DH_LIB);
 304                 return 0;
 305                 }
 306         EVP_PKEY_assign_DH(pkey, dh);
 307         return 1;
 308         }
 309
 310 static int dh_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
 311         {
 312         return i2d_DHparams(pkey->pkey.dh, pder);
 313         }
 314
 315 static int do_dh_print(BIO *bp, const DH *x, int indent,
 316                                                 ASN1_PCTX *ctx, int ptype)
 317         {
 318         unsigned char *m=NULL;
 319         int reason=ERR_R_BUF_LIB,ret=0;
 320         size_t buf_len=0;
 321
 322         const char *ktype = NULL;
 323
 324         BIGNUM *priv_key, *pub_key;
 325
 326         if (ptype == 2)
 327                 priv_key = x->priv_key;
 328         else
 329                 priv_key = NULL;
 330
 331         if (ptype > 0)
 332                 pub_key = x->pub_key;
 333         else
 334                 pub_key = NULL;
 335
 336         update_buflen(x->p, &buf_len);
 337
 338         if (buf_len == 0)
 339                 {
 340                 reason = ERR_R_PASSED_NULL_PARAMETER;
 341                 goto err;
 342                 }
 343
 344         update_buflen(x->g, &buf_len);
 345         update_buflen(pub_key, &buf_len);
 346         update_buflen(priv_key, &buf_len);
 347
 348         if (ptype == 2)
 349                 ktype = "PKCS#3 DH Private-Key";
 350         else if (ptype == 1)
 351                 ktype = "PKCS#3 DH Public-Key";
 352         else
 353                 ktype = "PKCS#3 DH Parameters";
 354
 355         m= OPENSSL_malloc(buf_len+10);
 356         if (m == NULL)
 357                 {
 358                 reason=ERR_R_MALLOC_FAILURE;
 359                 goto err;
 360                 }
 361
 362         BIO_indent(bp, indent, 128);
 363         if (BIO_printf(bp,"%s: (%d bit)\n", ktype, BN_num_bits(x->p)) <= 0)
 364                 goto err;
 365         indent += 4;
 366
 367         if (!ASN1_bn_print(bp,"private-key:",priv_key,m,indent)) goto err;
 368         if (!ASN1_bn_print(bp,"public-key:",pub_key,m,indent)) goto err;
 369
 370         if (!ASN1_bn_print(bp,"prime:",x->p,m,indent)) goto err;
 371         if (!ASN1_bn_print(bp,"generator:",x->g,m,indent)) goto err;
 372         if (x->length != 0)
 373                 {
 374                 BIO_indent(bp, indent, 128);
 375                 if (BIO_printf(bp,"recommended-private-length: %d bits\n",
 376                         (int)x->length) <= 0) goto err;
 377                 }
 378
 379
 380         ret=1;
 381         if (0)
 382                 {
 383 err:
 384                 DHerr(DH_F_DO_DH_PRINT,reason);
 385                 }
 386         if (m != NULL) OPENSSL_free(m);
 387         return(ret);
 388         }
 389
 390 static int int_dh_size(const EVP_PKEY *pkey)
 391         {
 392         return(DH_size(pkey->pkey.dh));
 393         }
 394
 395 static int dh_bits(const EVP_PKEY *pkey)
 396         {
 397         return BN_num_bits(pkey->pkey.dh->p);
 398         }
 399
 400 static int dh_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b)
 401         {
 402         if (    BN_cmp(a->pkey.dh->p,b->pkey.dh->p) ||
 403                 BN_cmp(a->pkey.dh->g,b->pkey.dh->g))
 404                 return 0;
 405         else
 406                 return 1;
 407         }
 408
 409 static int dh_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from)
 410         {
 411         BIGNUM *a;
 412
 413         if ((a=BN_dup(from->pkey.dh->p)) == NULL)
 414                 return 0;
 415         if (to->pkey.dh->p != NULL)
 416                 BN_free(to->pkey.dh->p);
 417         to->pkey.dh->p=a;
 418
 419         if ((a=BN_dup(from->pkey.dh->g)) == NULL)
 420                 return 0;
 421         if (to->pkey.dh->g != NULL)
 422                 BN_free(to->pkey.dh->g);
 423         to->pkey.dh->g=a;
 424
 425         return 1;
 426         }
 427
 428 static int dh_missing_parameters(const EVP_PKEY *a)
 429         {
 430         if (!a->pkey.dh->p || !a->pkey.dh->g)
 431                 return 1;
 432         return 0;
 433         }
 434
 435 static int dh_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b)
 436         {
 437         if (dh_cmp_parameters(a, b) == 0)
 438                 return 0;
 439         if (BN_cmp(b->pkey.dh->pub_key,a->pkey.dh->pub_key) != 0)
 440                 return 0;
 441         else
 442                 return 1;
 443         }
 444
 445 static int dh_param_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 446                                                         ASN1_PCTX *ctx)
 447         {
 448         return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 0);
 449         }
 450
 451 static int dh_public_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 452                                                         ASN1_PCTX *ctx)
 453         {
 454         return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 1);
 455         }
 456
 457 static int dh_private_print(BIO *bp, const EVP_PKEY *pkey, int indent,
 458                                                         ASN1_PCTX *ctx)
 459         {
 460         return do_dh_print(bp, pkey->pkey.dh, indent, ctx, 2);
 461         }
 462
 463 int DHparams_print(BIO *bp, const DH *x)
 464         {
 465         return do_dh_print(bp, x, 4, NULL, 0);
 466         }
 467
 468 const EVP_PKEY_ASN1_METHOD dh_asn1_meth =
 469         {
 470         EVP_PKEY_DH,
 471         EVP_PKEY_DH,
 472         0,
 473
 474         "DH",
 475         "OpenSSL PKCS#3 DH method",
 476
 477         dh_pub_decode,
 478         dh_pub_encode,
 479         dh_pub_cmp,
 480         dh_public_print,
 481
 482         dh_priv_decode,
 483         dh_priv_encode,
 484         dh_private_print,
 485
 486         int_dh_size,
 487         dh_bits,
 488
 489         dh_param_decode,
 490         dh_param_encode,
 491         dh_missing_parameters,
 492         dh_copy_parameters,
 493         dh_cmp_parameters,
 494         dh_param_print,
 495
 496         int_dh_free,
 497         0
 498         };
 499