contrib/bind-9.3/lib/dns/openssldh_link.c

   1 /*
   2  * Portions Copyright (C) 2004, 2006  Internet Systems Consortium, Inc. ("ISC")
   3  * Portions Copyright (C) 1999-2002  Internet Software Consortium.
   4  * Portions Copyright (C) 1995-2000 by Network Associates, Inc.
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC AND NETWORK ASSOCIATES DISCLAIMS
  11  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
  12  * WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE
  13  * FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
  16  * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 /*
  20  * Principal Author: Brian Wellington
  21  * $Id: openssldh_link.c,v 1.1.4.3 2006/03/02 00:37:20 marka Exp $
  22  */
  23
  24 #ifdef OPENSSL
  25
  26 #include <config.h>
  27
  28 #include <ctype.h>
  29
  30 #include <isc/mem.h>
  31 #include <isc/string.h>
  32 #include <isc/util.h>
  33
  34 #include <dst/result.h>
  35
  36 #include "dst_internal.h"
  37 #include "dst_openssl.h"
  38 #include "dst_parse.h"
  39
  40 #include <openssl/dh.h>
  41
  42 #define PRIME768 "FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088" \
  43         "A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25" \
  44         "F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A63A3620FFFFFFFFFFFFFFFF"
  45
  46 #define PRIME1024 "FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E08" \
  47         "8A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF2" \
  48         "5F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406" \
  49         "B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF"
  50
  51 #define PRIME1536 "FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD1" \
  52         "29024E088A67CC74020BBEA63B139B22514A08798E3404DD" \
  53         "EF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245" \
  54         "E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7ED" \
  55         "EE386BFB5A899FA5AE9F24117C4B1FE649286651ECE45B3D" \
  56         "C2007CB8A163BF0598DA48361C55D39A69163FA8FD24CF5F" \
  57         "83655D23DCA3AD961C62F356208552BB9ED529077096966D" \
  58         "670C354E4ABC9804F1746C08CA237327FFFFFFFFFFFFFFFF"
  59
  60
  61 static isc_result_t openssldh_todns(const dst_key_t *key, isc_buffer_t *data);
  62
  63 static BIGNUM bn2, bn768, bn1024, bn1536;
  64
  65 static isc_result_t
  66 openssldh_computesecret(const dst_key_t *pub, const dst_key_t *priv,
  67                         isc_buffer_t *secret)
  68 {
  69         DH *dhpub, *dhpriv;
  70         int ret;
  71         isc_region_t r;
  72         unsigned int len;
  73
  74         REQUIRE(pub->opaque != NULL);
  75         REQUIRE(priv->opaque != NULL);
  76
  77         dhpub = (DH *) pub->opaque;
  78         dhpriv = (DH *) priv->opaque;
  79
  80         len = DH_size(dhpriv);
  81         isc_buffer_availableregion(secret, &r);
  82         if (r.length < len)
  83                 return (ISC_R_NOSPACE);
  84         ret = DH_compute_key(r.base, dhpub->pub_key, dhpriv);
  85         if (ret == 0)
  86                 return (dst__openssl_toresult(DST_R_COMPUTESECRETFAILURE));
  87         isc_buffer_add(secret, len);
  88         return (ISC_R_SUCCESS);
  89 }
  90
  91 static isc_boolean_t
  92 openssldh_compare(const dst_key_t *key1, const dst_key_t *key2) {
  93         int status;
  94         DH *dh1, *dh2;
  95
  96         dh1 = (DH *) key1->opaque;
  97         dh2 = (DH *) key2->opaque;
  98
  99         if (dh1 == NULL && dh2 == NULL)
 100                 return (ISC_TRUE);
 101         else if (dh1 == NULL || dh2 == NULL)
 102                 return (ISC_FALSE);
 103
 104         status = BN_cmp(dh1->p, dh2->p) ||
 105                  BN_cmp(dh1->g, dh2->g) ||
 106                  BN_cmp(dh1->pub_key, dh2->pub_key);
 107
 108         if (status != 0)
 109                 return (ISC_FALSE);
 110
 111         if (dh1->priv_key != NULL || dh2->priv_key != NULL) {
 112                 if (dh1->priv_key == NULL || dh2->priv_key == NULL)
 113                         return (ISC_FALSE);
 114                 if (BN_cmp(dh1->priv_key, dh2->priv_key) != 0)
 115                         return (ISC_FALSE);
 116         }
 117         return (ISC_TRUE);
 118 }
 119
 120 static isc_boolean_t
 121 openssldh_paramcompare(const dst_key_t *key1, const dst_key_t *key2) {
 122         int status;
 123         DH *dh1, *dh2;
 124
 125         dh1 = (DH *) key1->opaque;
 126         dh2 = (DH *) key2->opaque;
 127
 128         if (dh1 == NULL && dh2 == NULL)
 129                 return (ISC_TRUE);
 130         else if (dh1 == NULL || dh2 == NULL)
 131                 return (ISC_FALSE);
 132
 133         status = BN_cmp(dh1->p, dh2->p) ||
 134                  BN_cmp(dh1->g, dh2->g);
 135
 136         if (status != 0)
 137                 return (ISC_FALSE);
 138         return (ISC_TRUE);
 139 }
 140
 141 #ifndef HAVE_DH_GENERATE_PARAMETERS
 142 /* ====================================================================
 143  * Copyright (c) 1998-2002 The OpenSSL Project.  All rights reserved.
 144  *
 145  * Redistribution and use in source and binary forms, with or without
 146  * modification, are permitted provided that the following conditions
 147  * are met:
 148  *
 149  * 1. Redistributions of source code must retain the above copyright
 150  *    notice, this list of conditions and the following disclaimer.
 151  *
 152  * 2. Redistributions in binary form must reproduce the above copyright
 153  *    notice, this list of conditions and the following disclaimer in
 154  *    the documentation and/or other materials provided with the
 155  *    distribution.
 156  *
 157  * 3. All advertising materials mentioning features or use of this
 158  *    software must display the following acknowledgment:
 159  *    "This product includes software developed by the OpenSSL Project
 160  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
 161  *
 162  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 163  *    endorse or promote products derived from this software without
 164  *    prior written permission. For written permission, please contact
 165  *    openssl-core@openssl.org.
 166  *
 167  * 5. Products derived from this software may not be called "OpenSSL"
 168  *    nor may "OpenSSL" appear in their names without prior written
 169  *    permission of the OpenSSL Project.
 170  *
 171  * 6. Redistributions of any form whatsoever must retain the following
 172  *    acknowledgment:
 173  *    "This product includes software developed by the OpenSSL Project
 174  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
 175  *
 176  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 177  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 178  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 179  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 180  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 181  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 182  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 183  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 184  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 185  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 186  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 187  * OF THE POSSIBILITY OF SUCH DAMAGE.
 188  * ====================================================================
 189  *
 190  * This product includes cryptographic software written by Eric Young
 191  * (eay@cryptsoft.com).  This product includes software written by Tim
 192  * Hudson (tjh@cryptsoft.com).
 193  *
 194  */
 195 static DH *
 196 DH_generate_parameters(int prime_len, int generator,
 197                        void (*callback)(int,int,void *), void *cb_arg)
 198 {
 199         BN_GENCB cb;
 200         DH *dh = NULL;
 201
 202         dh = DH_new();
 203         if (dh != NULL) {
 204                 BN_GENCB_set_old(&cb, callback, cb_arg);
 205
 206                 if (DH_generate_parameters_ex(dh, prime_len, generator, &cb))
 207                         return (dh);
 208                 DH_free(dh);
 209         }
 210         return (NULL);
 211 }
 212 #endif
 213
 214 static isc_result_t
 215 openssldh_generate(dst_key_t *key, int generator) {
 216         DH *dh = NULL;
 217
 218         if (generator == 0) {
 219                 if (key->key_size == 768 ||
 220                     key->key_size == 1024 ||
 221                     key->key_size == 1536)
 222                 {
 223                         dh = DH_new();
 224                         if (dh == NULL)
 225                                 return (ISC_R_NOMEMORY);
 226                         if (key->key_size == 768)
 227                                 dh->p = &bn768;
 228                         else if (key->key_size == 1024)
 229                                 dh->p = &bn1024;
 230                         else
 231                                 dh->p = &bn1536;
 232                         dh->g = &bn2;
 233                 }
 234                 else
 235                         generator = 2;
 236         }
 237
 238         if (generator != 0)
 239                 dh = DH_generate_parameters(key->key_size, generator,
 240                                             NULL, NULL);
 241
 242         if (dh == NULL)
 243                 return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
 244
 245         if (DH_generate_key(dh) == 0) {
 246                 DH_free(dh);
 247                 return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
 248         }
 249         dh->flags &= ~DH_FLAG_CACHE_MONT_P;
 250
 251         key->opaque = dh;
 252
 253         return (ISC_R_SUCCESS);
 254 }
 255
 256 static isc_boolean_t
 257 openssldh_isprivate(const dst_key_t *key) {
 258         DH *dh = (DH *) key->opaque;
 259         return (ISC_TF(dh != NULL && dh->priv_key != NULL));
 260 }
 261
 262 static void
 263 openssldh_destroy(dst_key_t *key) {
 264         DH *dh = key->opaque;
 265
 266         if (dh == NULL)
 267                 return;
 268
 269         if (dh->p == &bn768 || dh->p == &bn1024 || dh->p == &bn1536)
 270                 dh->p = NULL;
 271         if (dh->g == &bn2)
 272                 dh->g = NULL;
 273         DH_free(dh);
 274         key->opaque = NULL;
 275 }
 276
 277 static void
 278 uint16_toregion(isc_uint16_t val, isc_region_t *region) {
 279         *region->base++ = (val & 0xff00) >> 8;
 280         *region->base++ = (val & 0x00ff);
 281 }
 282
 283 static isc_uint16_t
 284 uint16_fromregion(isc_region_t *region) {
 285         isc_uint16_t val;
 286         unsigned char *cp = region->base;
 287
 288         val = ((unsigned int)(cp[0])) << 8;
 289         val |= ((unsigned int)(cp[1]));
 290
 291         region->base += 2;
 292         return (val);
 293 }
 294
 295 static isc_result_t
 296 openssldh_todns(const dst_key_t *key, isc_buffer_t *data) {
 297         DH *dh;
 298         isc_region_t r;
 299         isc_uint16_t dnslen, plen, glen, publen;
 300
 301         REQUIRE(key->opaque != NULL);
 302
 303         dh = (DH *) key->opaque;
 304
 305         isc_buffer_availableregion(data, &r);
 306
 307         if (dh->g == &bn2 &&
 308             (dh->p == &bn768 || dh->p == &bn1024 || dh->p == &bn1536)) {
 309                 plen = 1;
 310                 glen = 0;
 311         }
 312         else {
 313                 plen = BN_num_bytes(dh->p);
 314                 glen = BN_num_bytes(dh->g);
 315         }
 316         publen = BN_num_bytes(dh->pub_key);
 317         dnslen = plen + glen + publen + 6;
 318         if (r.length < (unsigned int) dnslen)
 319                 return (ISC_R_NOSPACE);
 320
 321         uint16_toregion(plen, &r);
 322         if (plen == 1) {
 323                 if (dh->p == &bn768)
 324                         *r.base = 1;
 325                 else if (dh->p == &bn1024)
 326                         *r.base = 2;
 327                 else
 328                         *r.base = 3;
 329         }
 330         else
 331                 BN_bn2bin(dh->p, r.base);
 332         r.base += plen;
 333
 334         uint16_toregion(glen, &r);
 335         if (glen > 0)
 336                 BN_bn2bin(dh->g, r.base);
 337         r.base += glen;
 338
 339         uint16_toregion(publen, &r);
 340         BN_bn2bin(dh->pub_key, r.base);
 341         r.base += publen;
 342
 343         isc_buffer_add(data, dnslen);
 344
 345         return (ISC_R_SUCCESS);
 346 }
 347
 348 static isc_result_t
 349 openssldh_fromdns(dst_key_t *key, isc_buffer_t *data) {
 350         DH *dh;
 351         isc_region_t r;
 352         isc_uint16_t plen, glen, publen;
 353         int special = 0;
 354
 355         isc_buffer_remainingregion(data, &r);
 356         if (r.length == 0)
 357                 return (ISC_R_SUCCESS);
 358
 359         dh = DH_new();
 360         if (dh == NULL)
 361                 return (ISC_R_NOMEMORY);
 362         dh->flags &= ~DH_FLAG_CACHE_MONT_P;
 363
 364         /*
 365          * Read the prime length.  1 & 2 are table entries, > 16 means a
 366          * prime follows, otherwise an error.
 367          */
 368         if (r.length < 2) {
 369                 DH_free(dh);
 370                 return (DST_R_INVALIDPUBLICKEY);
 371         }
 372         plen = uint16_fromregion(&r);
 373         if (plen < 16 && plen != 1 && plen != 2) {
 374                 DH_free(dh);
 375                 return (DST_R_INVALIDPUBLICKEY);
 376         }
 377         if (r.length < plen) {
 378                 DH_free(dh);
 379                 return (DST_R_INVALIDPUBLICKEY);
 380         }
 381         if (plen == 1 || plen == 2) {
 382                 if (plen == 1)
 383                         special = *r.base++;
 384                 else
 385                         special = uint16_fromregion(&r);
 386                 switch (special) {
 387                         case 1:
 388                                 dh->p = &bn768;
 389                                 break;
 390                         case 2:
 391                                 dh->p = &bn1024;
 392                                 break;
 393                         case 3:
 394                                 dh->p = &bn1536;
 395                                 break;
 396                         default:
 397                                 DH_free(dh);
 398                                 return (DST_R_INVALIDPUBLICKEY);
 399                 }
 400         }
 401         else {
 402                 dh->p = BN_bin2bn(r.base, plen, NULL);
 403                 r.base += plen;
 404         }
 405
 406         /*
 407          * Read the generator length.  This should be 0 if the prime was
 408          * special, but it might not be.  If it's 0 and the prime is not
 409          * special, we have a problem.
 410          */
 411         if (r.length < 2) {
 412                 DH_free(dh);
 413                 return (DST_R_INVALIDPUBLICKEY);
 414         }
 415         glen = uint16_fromregion(&r);
 416         if (r.length < glen) {
 417                 DH_free(dh);
 418                 return (DST_R_INVALIDPUBLICKEY);
 419         }
 420         if (special != 0) {
 421                 if (glen == 0)
 422                         dh->g = &bn2;
 423                 else {
 424                         dh->g = BN_bin2bn(r.base, glen, NULL);
 425                         if (BN_cmp(dh->g, &bn2) == 0) {
 426                                 BN_free(dh->g);
 427                                 dh->g = &bn2;
 428                         }
 429                         else {
 430                                 DH_free(dh);
 431                                 return (DST_R_INVALIDPUBLICKEY);
 432                         }
 433                 }
 434         }
 435         else {
 436                 if (glen == 0) {
 437                         DH_free(dh);
 438                         return (DST_R_INVALIDPUBLICKEY);
 439                 }
 440                 dh->g = BN_bin2bn(r.base, glen, NULL);
 441         }
 442         r.base += glen;
 443
 444         if (r.length < 2) {
 445                 DH_free(dh);
 446                 return (DST_R_INVALIDPUBLICKEY);
 447         }
 448         publen = uint16_fromregion(&r);
 449         if (r.length < publen) {
 450                 DH_free(dh);
 451                 return (DST_R_INVALIDPUBLICKEY);
 452         }
 453         dh->pub_key = BN_bin2bn(r.base, publen, NULL);
 454         r.base += publen;
 455
 456         key->key_size = BN_num_bits(dh->p);
 457
 458         isc_buffer_forward(data, plen + glen + publen + 6);
 459
 460         key->opaque = (void *) dh;
 461
 462         return (ISC_R_SUCCESS);
 463 }
 464
 465 static isc_result_t
 466 openssldh_tofile(const dst_key_t *key, const char *directory) {
 467         int i;
 468         DH *dh;
 469         dst_private_t priv;
 470         unsigned char *bufs[4];
 471         isc_result_t result;
 472
 473         if (key->opaque == NULL)
 474                 return (DST_R_NULLKEY);
 475
 476         dh = (DH *) key->opaque;
 477
 478         for (i = 0; i < 4; i++) {
 479                 bufs[i] = isc_mem_get(key->mctx, BN_num_bytes(dh->p));
 480                 if (bufs[i] == NULL) {
 481                         result = ISC_R_NOMEMORY;
 482                         goto fail;
 483                 }
 484         }
 485
 486         i = 0;
 487
 488         priv.elements[i].tag = TAG_DH_PRIME;
 489         priv.elements[i].length = BN_num_bytes(dh->p);
 490         BN_bn2bin(dh->p, bufs[i]);
 491         priv.elements[i].data = bufs[i];
 492         i++;
 493
 494         priv.elements[i].tag = TAG_DH_GENERATOR;
 495         priv.elements[i].length = BN_num_bytes(dh->g);
 496         BN_bn2bin(dh->g, bufs[i]);
 497         priv.elements[i].data = bufs[i];
 498         i++;
 499
 500         priv.elements[i].tag = TAG_DH_PRIVATE;
 501         priv.elements[i].length = BN_num_bytes(dh->priv_key);
 502         BN_bn2bin(dh->priv_key, bufs[i]);
 503         priv.elements[i].data = bufs[i];
 504         i++;
 505
 506         priv.elements[i].tag = TAG_DH_PUBLIC;
 507         priv.elements[i].length = BN_num_bytes(dh->pub_key);
 508         BN_bn2bin(dh->pub_key, bufs[i]);
 509         priv.elements[i].data = bufs[i];
 510         i++;
 511
 512         priv.nelements = i;
 513         result = dst__privstruct_writefile(key, &priv, directory);
 514  fail:
 515         for (i = 0; i < 4; i++) {
 516                 if (bufs[i] == NULL)
 517                         break;
 518                 isc_mem_put(key->mctx, bufs[i], BN_num_bytes(dh->p));
 519         }
 520         return (result);
 521 }
 522
 523 static isc_result_t
 524 openssldh_parse(dst_key_t *key, isc_lex_t *lexer) {
 525         dst_private_t priv;
 526         isc_result_t ret;
 527         int i;
 528         DH *dh = NULL;
 529         isc_mem_t *mctx;
 530 #define DST_RET(a) {ret = a; goto err;}
 531
 532         mctx = key->mctx;
 533
 534         /* read private key file */
 535         ret = dst__privstruct_parse(key, DST_ALG_DH, lexer, mctx, &priv);
 536         if (ret != ISC_R_SUCCESS)
 537                 return (ret);
 538
 539         dh = DH_new();
 540         if (dh == NULL)
 541                 DST_RET(ISC_R_NOMEMORY);
 542         dh->flags &= ~DH_FLAG_CACHE_MONT_P;
 543         key->opaque = dh;
 544
 545         for (i = 0; i < priv.nelements; i++) {
 546                 BIGNUM *bn;
 547                 bn = BN_bin2bn(priv.elements[i].data,
 548                                priv.elements[i].length, NULL);
 549                 if (bn == NULL)
 550                         DST_RET(ISC_R_NOMEMORY);
 551
 552                 switch (priv.elements[i].tag) {
 553                         case TAG_DH_PRIME:
 554                                 dh->p = bn;
 555                                 break;
 556                         case TAG_DH_GENERATOR:
 557                                 dh->g = bn;
 558                                 break;
 559                         case TAG_DH_PRIVATE:
 560                                 dh->priv_key = bn;
 561                                 break;
 562                         case TAG_DH_PUBLIC:
 563                                 dh->pub_key = bn;
 564                                 break;
 565                 }
 566         }
 567         dst__privstruct_free(&priv, mctx);
 568
 569         key->key_size = BN_num_bits(dh->p);
 570
 571         if ((key->key_size == 768 ||
 572              key->key_size == 1024 ||
 573              key->key_size == 1536) &&
 574             BN_cmp(dh->g, &bn2) == 0)
 575         {
 576                 if (key->key_size == 768 && BN_cmp(dh->p, &bn768) == 0) {
 577                         BN_free(dh->p);
 578                         BN_free(dh->g);
 579                         dh->p = &bn768;
 580                         dh->g = &bn2;
 581                 } else if (key->key_size == 1024 &&
 582                            BN_cmp(dh->p, &bn1024) == 0) {
 583                         BN_free(dh->p);
 584                         BN_free(dh->g);
 585                         dh->p = &bn1024;
 586                         dh->g = &bn2;
 587                 } else if (key->key_size == 1536 &&
 588                            BN_cmp(dh->p, &bn1536) == 0) {
 589                         BN_free(dh->p);
 590                         BN_free(dh->g);
 591                         dh->p = &bn1536;
 592                         dh->g = &bn2;
 593                 }
 594         }
 595
 596         return (ISC_R_SUCCESS);
 597
 598  err:
 599         openssldh_destroy(key);
 600         dst__privstruct_free(&priv, mctx);
 601         memset(&priv, 0, sizeof(priv));
 602         return (ret);
 603 }
 604
 605 static void
 606 BN_fromhex(BIGNUM *b, const char *str) {
 607         static const char hexdigits[] = "0123456789abcdef";
 608         unsigned char data[512];
 609         unsigned int i;
 610         BIGNUM *out;
 611
 612         RUNTIME_CHECK(strlen(str) < 1024U && strlen(str) % 2 == 0U);
 613         for (i = 0; i < strlen(str); i += 2) {
 614                 char *s;
 615                 unsigned int high, low;
 616
 617                 s = strchr(hexdigits, tolower((unsigned char)str[i]));
 618                 RUNTIME_CHECK(s != NULL);
 619                 high = s - hexdigits;
 620
 621                 s = strchr(hexdigits, tolower((unsigned char)str[i + 1]));
 622                 RUNTIME_CHECK(s != NULL);
 623                 low = s - hexdigits;
 624
 625                 data[i/2] = (unsigned char)((high << 4) + low);
 626         }
 627         out = BN_bin2bn(data, strlen(str)/2, b);
 628         RUNTIME_CHECK(out != NULL);
 629 }
 630
 631 static void
 632 openssldh_cleanup(void) {
 633         BN_free(&bn2);
 634         BN_free(&bn768);
 635         BN_free(&bn1024);
 636         BN_free(&bn1536);
 637 }
 638
 639 static dst_func_t openssldh_functions = {
 640         NULL, /* createctx */
 641         NULL, /* destroyctx */
 642         NULL, /* adddata */
 643         NULL, /* openssldh_sign */
 644         NULL, /* openssldh_verify */
 645         openssldh_computesecret,
 646         openssldh_compare,
 647         openssldh_paramcompare,
 648         openssldh_generate,
 649         openssldh_isprivate,
 650         openssldh_destroy,
 651         openssldh_todns,
 652         openssldh_fromdns,
 653         openssldh_tofile,
 654         openssldh_parse,
 655         openssldh_cleanup,
 656 };
 657
 658 isc_result_t
 659 dst__openssldh_init(dst_func_t **funcp) {
 660         REQUIRE(funcp != NULL);
 661         if (*funcp == NULL) {
 662                 BN_init(&bn2);
 663                 BN_init(&bn768);
 664                 BN_init(&bn1024);
 665                 BN_init(&bn1536);
 666                 BN_set_word(&bn2, 2);
 667                 BN_fromhex(&bn768, PRIME768);
 668                 BN_fromhex(&bn1024, PRIME1024);
 669                 BN_fromhex(&bn1536, PRIME1536);
 670                 *funcp = &openssldh_functions;
 671         }
 672         return (ISC_R_SUCCESS);
 673 }
 674
 675 #else /* OPENSSL */
 676
 677 #include <isc/util.h>
 678
 679 EMPTY_TRANSLATION_UNIT
 680
 681 #endif /* OPENSSL */