crypto/pem/pvkfmt.c

   1 /*
   2  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
   3  * 2005.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 2005 The OpenSSL Project.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in
  17  *    the documentation and/or other materials provided with the
  18  *    distribution.
  19  *
  20  * 3. All advertising materials mentioning features or use of this
  21  *    software must display the following acknowledgment:
  22  *    "This product includes software developed by the OpenSSL Project
  23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  24  *
  25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  26  *    endorse or promote products derived from this software without
  27  *    prior written permission. For written permission, please contact
  28  *    licensing@OpenSSL.org.
  29  *
  30  * 5. Products derived from this software may not be called "OpenSSL"
  31  *    nor may "OpenSSL" appear in their names without prior written
  32  *    permission of the OpenSSL Project.
  33  *
  34  * 6. Redistributions of any form whatsoever must retain the following
  35  *    acknowledgment:
  36  *    "This product includes software developed by the OpenSSL Project
  37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  38  *
  39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  50  * OF THE POSSIBILITY OF SUCH DAMAGE.
  51  * ====================================================================
  52  *
  53  * This product includes cryptographic software written by Eric Young
  54  * (eay@cryptsoft.com).  This product includes software written by Tim
  55  * Hudson (tjh@cryptsoft.com).
  56  *
  57  */
  58
  59 /*
  60  * Support for PVK format keys and related structures (such a PUBLICKEYBLOB
  61  * and PRIVATEKEYBLOB).
  62  */
  63
  64 #include "cryptlib.h"
  65 #include <openssl/pem.h>
  66 #include <openssl/rand.h>
  67 #include <openssl/bn.h>
  68 #if !defined(OPENSSL_NO_RSA) && !defined(OPENSSL_NO_DSA)
  69 # include <openssl/dsa.h>
  70 # include <openssl/rsa.h>
  71
  72 /*
  73  * Utility function: read a DWORD (4 byte unsigned integer) in little endian
  74  * format
  75  */
  76
  77 static unsigned int read_ledword(const unsigned char **in)
  78 {
  79     const unsigned char *p = *in;
  80     unsigned int ret;
  81     ret = *p++;
  82     ret |= (*p++ << 8);
  83     ret |= (*p++ << 16);
  84     ret |= (*p++ << 24);
  85     *in = p;
  86     return ret;
  87 }
  88
  89 /*
  90  * Read a BIGNUM in little endian format. The docs say that this should take
  91  * up bitlen/8 bytes.
  92  */
  93
  94 static int read_lebn(const unsigned char **in, unsigned int nbyte, BIGNUM **r)
  95 {
  96     const unsigned char *p;
  97     unsigned char *tmpbuf, *q;
  98     unsigned int i;
  99     p = *in + nbyte - 1;
 100     tmpbuf = OPENSSL_malloc(nbyte);
 101     if (!tmpbuf)
 102         return 0;
 103     q = tmpbuf;
 104     for (i = 0; i < nbyte; i++)
 105         *q++ = *p--;
 106     *r = BN_bin2bn(tmpbuf, nbyte, NULL);
 107     OPENSSL_free(tmpbuf);
 108     if (*r) {
 109         *in += nbyte;
 110         return 1;
 111     } else
 112         return 0;
 113 }
 114
 115 /* Convert private key blob to EVP_PKEY: RSA and DSA keys supported */
 116
 117 # define MS_PUBLICKEYBLOB        0x6
 118 # define MS_PRIVATEKEYBLOB       0x7
 119 # define MS_RSA1MAGIC            0x31415352L
 120 # define MS_RSA2MAGIC            0x32415352L
 121 # define MS_DSS1MAGIC            0x31535344L
 122 # define MS_DSS2MAGIC            0x32535344L
 123
 124 # define MS_KEYALG_RSA_KEYX      0xa400
 125 # define MS_KEYALG_DSS_SIGN      0x2200
 126
 127 # define MS_KEYTYPE_KEYX         0x1
 128 # define MS_KEYTYPE_SIGN         0x2
 129
 130 /* The PVK file magic number: seems to spell out "bobsfile", who is Bob? */
 131 # define MS_PVKMAGIC             0xb0b5f11eL
 132 /* Salt length for PVK files */
 133 # define PVK_SALTLEN             0x10
 134
 135 static EVP_PKEY *b2i_rsa(const unsigned char **in, unsigned int length,
 136                          unsigned int bitlen, int ispub);
 137 static EVP_PKEY *b2i_dss(const unsigned char **in, unsigned int length,
 138                          unsigned int bitlen, int ispub);
 139
 140 static int do_blob_header(const unsigned char **in, unsigned int length,
 141                           unsigned int *pmagic, unsigned int *pbitlen,
 142                           int *pisdss, int *pispub)
 143 {
 144     const unsigned char *p = *in;
 145     if (length < 16)
 146         return 0;
 147     /* bType */
 148     if (*p == MS_PUBLICKEYBLOB) {
 149         if (*pispub == 0) {
 150             PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PRIVATE_KEY_BLOB);
 151             return 0;
 152         }
 153         *pispub = 1;
 154     } else if (*p == MS_PRIVATEKEYBLOB) {
 155         if (*pispub == 1) {
 156             PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PUBLIC_KEY_BLOB);
 157             return 0;
 158         }
 159         *pispub = 0;
 160     } else
 161         return 0;
 162     p++;
 163     /* Version */
 164     if (*p++ != 0x2) {
 165         PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_BAD_VERSION_NUMBER);
 166         return 0;
 167     }
 168     /* Ignore reserved, aiKeyAlg */
 169     p += 6;
 170     *pmagic = read_ledword(&p);
 171     *pbitlen = read_ledword(&p);
 172     *pisdss = 0;
 173     switch (*pmagic) {
 174
 175     case MS_DSS1MAGIC:
 176         *pisdss = 1;
 177     case MS_RSA1MAGIC:
 178         if (*pispub == 0) {
 179             PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PRIVATE_KEY_BLOB);
 180             return 0;
 181         }
 182         break;
 183
 184     case MS_DSS2MAGIC:
 185         *pisdss = 1;
 186     case MS_RSA2MAGIC:
 187         if (*pispub == 1) {
 188             PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PUBLIC_KEY_BLOB);
 189             return 0;
 190         }
 191         break;
 192
 193     default:
 194         PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_BAD_MAGIC_NUMBER);
 195         return -1;
 196     }
 197     *in = p;
 198     return 1;
 199 }
 200
 201 static unsigned int blob_length(unsigned bitlen, int isdss, int ispub)
 202 {
 203     unsigned int nbyte, hnbyte;
 204     nbyte = (bitlen + 7) >> 3;
 205     hnbyte = (bitlen + 15) >> 4;
 206     if (isdss) {
 207
 208         /*
 209          * Expected length: 20 for q + 3 components bitlen each + 24 for seed
 210          * structure.
 211          */
 212         if (ispub)
 213             return 44 + 3 * nbyte;
 214         /*
 215          * Expected length: 20 for q, priv, 2 bitlen components + 24 for seed
 216          * structure.
 217          */
 218         else
 219             return 64 + 2 * nbyte;
 220     } else {
 221         /* Expected length: 4 for 'e' + 'n' */
 222         if (ispub)
 223             return 4 + nbyte;
 224         else
 225             /*
 226              * Expected length: 4 for 'e' and 7 other components. 2
 227              * components are bitlen size, 5 are bitlen/2
 228              */
 229             return 4 + 2 * nbyte + 5 * hnbyte;
 230     }
 231
 232 }
 233
 234 static EVP_PKEY *do_b2i(const unsigned char **in, unsigned int length,
 235                         int ispub)
 236 {
 237     const unsigned char *p = *in;
 238     unsigned int bitlen, magic;
 239     int isdss;
 240     if (do_blob_header(&p, length, &magic, &bitlen, &isdss, &ispub) <= 0) {
 241         PEMerr(PEM_F_DO_B2I, PEM_R_KEYBLOB_HEADER_PARSE_ERROR);
 242         return NULL;
 243     }
 244     length -= 16;
 245     if (length < blob_length(bitlen, isdss, ispub)) {
 246         PEMerr(PEM_F_DO_B2I, PEM_R_KEYBLOB_TOO_SHORT);
 247         return NULL;
 248     }
 249     if (isdss)
 250         return b2i_dss(&p, length, bitlen, ispub);
 251     else
 252         return b2i_rsa(&p, length, bitlen, ispub);
 253 }
 254
 255 static EVP_PKEY *do_b2i_bio(BIO *in, int ispub)
 256 {
 257     const unsigned char *p;
 258     unsigned char hdr_buf[16], *buf = NULL;
 259     unsigned int bitlen, magic, length;
 260     int isdss;
 261     EVP_PKEY *ret = NULL;
 262     if (BIO_read(in, hdr_buf, 16) != 16) {
 263         PEMerr(PEM_F_DO_B2I_BIO, PEM_R_KEYBLOB_TOO_SHORT);
 264         return NULL;
 265     }
 266     p = hdr_buf;
 267     if (do_blob_header(&p, 16, &magic, &bitlen, &isdss, &ispub) <= 0)
 268         return NULL;
 269
 270     length = blob_length(bitlen, isdss, ispub);
 271     buf = OPENSSL_malloc(length);
 272     if (!buf) {
 273         PEMerr(PEM_F_DO_B2I_BIO, ERR_R_MALLOC_FAILURE);
 274         goto err;
 275     }
 276     p = buf;
 277     if (BIO_read(in, buf, length) != (int)length) {
 278         PEMerr(PEM_F_DO_B2I_BIO, PEM_R_KEYBLOB_TOO_SHORT);
 279         goto err;
 280     }
 281
 282     if (isdss)
 283         ret = b2i_dss(&p, length, bitlen, ispub);
 284     else
 285         ret = b2i_rsa(&p, length, bitlen, ispub);
 286
 287  err:
 288     if (buf)
 289         OPENSSL_free(buf);
 290     return ret;
 291 }
 292
 293 static EVP_PKEY *b2i_dss(const unsigned char **in, unsigned int length,
 294                          unsigned int bitlen, int ispub)
 295 {
 296     const unsigned char *p = *in;
 297     EVP_PKEY *ret = NULL;
 298     DSA *dsa = NULL;
 299     BN_CTX *ctx = NULL;
 300     unsigned int nbyte;
 301     nbyte = (bitlen + 7) >> 3;
 302
 303     dsa = DSA_new();
 304     ret = EVP_PKEY_new();
 305     if (!dsa || !ret)
 306         goto memerr;
 307     if (!read_lebn(&p, nbyte, &dsa->p))
 308         goto memerr;
 309     if (!read_lebn(&p, 20, &dsa->q))
 310         goto memerr;
 311     if (!read_lebn(&p, nbyte, &dsa->g))
 312         goto memerr;
 313     if (ispub) {
 314         if (!read_lebn(&p, nbyte, &dsa->pub_key))
 315             goto memerr;
 316     } else {
 317         if (!read_lebn(&p, 20, &dsa->priv_key))
 318             goto memerr;
 319         /* Calculate public key */
 320         if (!(dsa->pub_key = BN_new()))
 321             goto memerr;
 322         if (!(ctx = BN_CTX_new()))
 323             goto memerr;
 324
 325         if (!BN_mod_exp(dsa->pub_key, dsa->g, dsa->priv_key, dsa->p, ctx))
 326
 327             goto memerr;
 328         BN_CTX_free(ctx);
 329     }
 330
 331     EVP_PKEY_set1_DSA(ret, dsa);
 332     DSA_free(dsa);
 333     *in = p;
 334     return ret;
 335
 336  memerr:
 337     PEMerr(PEM_F_B2I_DSS, ERR_R_MALLOC_FAILURE);
 338     DSA_free(dsa);
 339     EVP_PKEY_free(ret);
 340     BN_CTX_free(ctx);
 341     return NULL;
 342 }
 343
 344 static EVP_PKEY *b2i_rsa(const unsigned char **in, unsigned int length,
 345                          unsigned int bitlen, int ispub)
 346 {
 347     const unsigned char *p = *in;
 348     EVP_PKEY *ret = NULL;
 349     RSA *rsa = NULL;
 350     unsigned int nbyte, hnbyte;
 351     nbyte = (bitlen + 7) >> 3;
 352     hnbyte = (bitlen + 15) >> 4;
 353     rsa = RSA_new();
 354     ret = EVP_PKEY_new();
 355     if (!rsa || !ret)
 356         goto memerr;
 357     rsa->e = BN_new();
 358     if (!rsa->e)
 359         goto memerr;
 360     if (!BN_set_word(rsa->e, read_ledword(&p)))
 361         goto memerr;
 362     if (!read_lebn(&p, nbyte, &rsa->n))
 363         goto memerr;
 364     if (!ispub) {
 365         if (!read_lebn(&p, hnbyte, &rsa->p))
 366             goto memerr;
 367         if (!read_lebn(&p, hnbyte, &rsa->q))
 368             goto memerr;
 369         if (!read_lebn(&p, hnbyte, &rsa->dmp1))
 370             goto memerr;
 371         if (!read_lebn(&p, hnbyte, &rsa->dmq1))
 372             goto memerr;
 373         if (!read_lebn(&p, hnbyte, &rsa->iqmp))
 374             goto memerr;
 375         if (!read_lebn(&p, nbyte, &rsa->d))
 376             goto memerr;
 377     }
 378
 379     EVP_PKEY_set1_RSA(ret, rsa);
 380     RSA_free(rsa);
 381     *in = p;
 382     return ret;
 383  memerr:
 384     PEMerr(PEM_F_B2I_RSA, ERR_R_MALLOC_FAILURE);
 385     RSA_free(rsa);
 386     EVP_PKEY_free(ret);
 387     return NULL;
 388 }
 389
 390 EVP_PKEY *b2i_PrivateKey(const unsigned char **in, long length)
 391 {
 392     return do_b2i(in, length, 0);
 393 }
 394
 395 EVP_PKEY *b2i_PublicKey(const unsigned char **in, long length)
 396 {
 397     return do_b2i(in, length, 1);
 398 }
 399
 400 EVP_PKEY *b2i_PrivateKey_bio(BIO *in)
 401 {
 402     return do_b2i_bio(in, 0);
 403 }
 404
 405 EVP_PKEY *b2i_PublicKey_bio(BIO *in)
 406 {
 407     return do_b2i_bio(in, 1);
 408 }
 409
 410 static void write_ledword(unsigned char **out, unsigned int dw)
 411 {
 412     unsigned char *p = *out;
 413     *p++ = dw & 0xff;
 414     *p++ = (dw >> 8) & 0xff;
 415     *p++ = (dw >> 16) & 0xff;
 416     *p++ = (dw >> 24) & 0xff;
 417     *out = p;
 418 }
 419
 420 static void write_lebn(unsigned char **out, const BIGNUM *bn, int len)
 421 {
 422     int nb, i;
 423     unsigned char *p = *out, *q, c;
 424     nb = BN_num_bytes(bn);
 425     BN_bn2bin(bn, p);
 426     q = p + nb - 1;
 427     /* In place byte order reversal */
 428     for (i = 0; i < nb / 2; i++) {
 429         c = *p;
 430         *p++ = *q;
 431         *q-- = c;
 432     }
 433     *out += nb;
 434     /* Pad with zeroes if we have to */
 435     if (len > 0) {
 436         len -= nb;
 437         if (len > 0) {
 438             memset(*out, 0, len);
 439             *out += len;
 440         }
 441     }
 442 }
 443
 444 static int check_bitlen_rsa(RSA *rsa, int ispub, unsigned int *magic);
 445 static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *magic);
 446
 447 static void write_rsa(unsigned char **out, RSA *rsa, int ispub);
 448 static void write_dsa(unsigned char **out, DSA *dsa, int ispub);
 449
 450 static int do_i2b(unsigned char **out, EVP_PKEY *pk, int ispub)
 451 {
 452     unsigned char *p;
 453     unsigned int bitlen, magic = 0, keyalg;
 454     int outlen, noinc = 0;
 455     if (pk->type == EVP_PKEY_DSA) {
 456         bitlen = check_bitlen_dsa(pk->pkey.dsa, ispub, &magic);
 457         keyalg = MS_KEYALG_DSS_SIGN;
 458     } else if (pk->type == EVP_PKEY_RSA) {
 459         bitlen = check_bitlen_rsa(pk->pkey.rsa, ispub, &magic);
 460         keyalg = MS_KEYALG_RSA_KEYX;
 461     } else
 462         return -1;
 463     if (bitlen == 0)
 464         return -1;
 465     outlen = 16 + blob_length(bitlen,
 466                               keyalg == MS_KEYALG_DSS_SIGN ? 1 : 0, ispub);
 467     if (out == NULL)
 468         return outlen;
 469     if (*out)
 470         p = *out;
 471     else {
 472         p = OPENSSL_malloc(outlen);
 473         if (!p)
 474             return -1;
 475         *out = p;
 476         noinc = 1;
 477     }
 478     if (ispub)
 479         *p++ = MS_PUBLICKEYBLOB;
 480     else
 481         *p++ = MS_PRIVATEKEYBLOB;
 482     *p++ = 0x2;
 483     *p++ = 0;
 484     *p++ = 0;
 485     write_ledword(&p, keyalg);
 486     write_ledword(&p, magic);
 487     write_ledword(&p, bitlen);
 488     if (keyalg == MS_KEYALG_DSS_SIGN)
 489         write_dsa(&p, pk->pkey.dsa, ispub);
 490     else
 491         write_rsa(&p, pk->pkey.rsa, ispub);
 492     if (!noinc)
 493         *out += outlen;
 494     return outlen;
 495 }
 496
 497 static int do_i2b_bio(BIO *out, EVP_PKEY *pk, int ispub)
 498 {
 499     unsigned char *tmp = NULL;
 500     int outlen, wrlen;
 501     outlen = do_i2b(&tmp, pk, ispub);
 502     if (outlen < 0)
 503         return -1;
 504     wrlen = BIO_write(out, tmp, outlen);
 505     OPENSSL_free(tmp);
 506     if (wrlen == outlen)
 507         return outlen;
 508     return -1;
 509 }
 510
 511 static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *pmagic)
 512 {
 513     int bitlen;
 514     bitlen = BN_num_bits(dsa->p);
 515     if ((bitlen & 7) || (BN_num_bits(dsa->q) != 160)
 516         || (BN_num_bits(dsa->g) > bitlen))
 517         goto badkey;
 518     if (ispub) {
 519         if (BN_num_bits(dsa->pub_key) > bitlen)
 520             goto badkey;
 521         *pmagic = MS_DSS1MAGIC;
 522     } else {
 523         if (BN_num_bits(dsa->priv_key) > 160)
 524             goto badkey;
 525         *pmagic = MS_DSS2MAGIC;
 526     }
 527
 528     return bitlen;
 529  badkey:
 530     PEMerr(PEM_F_CHECK_BITLEN_DSA, PEM_R_UNSUPPORTED_KEY_COMPONENTS);
 531     return 0;
 532 }
 533
 534 static int check_bitlen_rsa(RSA *rsa, int ispub, unsigned int *pmagic)
 535 {
 536     int nbyte, hnbyte, bitlen;
 537     if (BN_num_bits(rsa->e) > 32)
 538         goto badkey;
 539     bitlen = BN_num_bits(rsa->n);
 540     nbyte = BN_num_bytes(rsa->n);
 541     hnbyte = (BN_num_bits(rsa->n) + 15) >> 4;
 542     if (ispub) {
 543         *pmagic = MS_RSA1MAGIC;
 544         return bitlen;
 545     } else {
 546         *pmagic = MS_RSA2MAGIC;
 547         /*
 548          * For private key each component must fit within nbyte or hnbyte.
 549          */
 550         if (BN_num_bytes(rsa->d) > nbyte)
 551             goto badkey;
 552         if ((BN_num_bytes(rsa->iqmp) > hnbyte)
 553             || (BN_num_bytes(rsa->p) > hnbyte)
 554             || (BN_num_bytes(rsa->q) > hnbyte)
 555             || (BN_num_bytes(rsa->dmp1) > hnbyte)
 556             || (BN_num_bytes(rsa->dmq1) > hnbyte))
 557             goto badkey;
 558     }
 559     return bitlen;
 560  badkey:
 561     PEMerr(PEM_F_CHECK_BITLEN_RSA, PEM_R_UNSUPPORTED_KEY_COMPONENTS);
 562     return 0;
 563 }
 564
 565 static void write_rsa(unsigned char **out, RSA *rsa, int ispub)
 566 {
 567     int nbyte, hnbyte;
 568     nbyte = BN_num_bytes(rsa->n);
 569     hnbyte = (BN_num_bits(rsa->n) + 15) >> 4;
 570     write_lebn(out, rsa->e, 4);
 571     write_lebn(out, rsa->n, -1);
 572     if (ispub)
 573         return;
 574     write_lebn(out, rsa->p, hnbyte);
 575     write_lebn(out, rsa->q, hnbyte);
 576     write_lebn(out, rsa->dmp1, hnbyte);
 577     write_lebn(out, rsa->dmq1, hnbyte);
 578     write_lebn(out, rsa->iqmp, hnbyte);
 579     write_lebn(out, rsa->d, nbyte);
 580 }
 581
 582 static void write_dsa(unsigned char **out, DSA *dsa, int ispub)
 583 {
 584     int nbyte;
 585     nbyte = BN_num_bytes(dsa->p);
 586     write_lebn(out, dsa->p, nbyte);
 587     write_lebn(out, dsa->q, 20);
 588     write_lebn(out, dsa->g, nbyte);
 589     if (ispub)
 590         write_lebn(out, dsa->pub_key, nbyte);
 591     else
 592         write_lebn(out, dsa->priv_key, 20);
 593     /* Set "invalid" for seed structure values */
 594     memset(*out, 0xff, 24);
 595     *out += 24;
 596     return;
 597 }
 598
 599 int i2b_PrivateKey_bio(BIO *out, EVP_PKEY *pk)
 600 {
 601     return do_i2b_bio(out, pk, 0);
 602 }
 603
 604 int i2b_PublicKey_bio(BIO *out, EVP_PKEY *pk)
 605 {
 606     return do_i2b_bio(out, pk, 1);
 607 }
 608
 609 # ifndef OPENSSL_NO_RC4
 610
 611 static int do_PVK_header(const unsigned char **in, unsigned int length,
 612                          int skip_magic,
 613                          unsigned int *psaltlen, unsigned int *pkeylen)
 614 {
 615     const unsigned char *p = *in;
 616     unsigned int pvk_magic, is_encrypted;
 617     if (skip_magic) {
 618         if (length < 20) {
 619             PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
 620             return 0;
 621         }
 622         length -= 20;
 623     } else {
 624         if (length < 24) {
 625             PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
 626             return 0;
 627         }
 628         length -= 24;
 629         pvk_magic = read_ledword(&p);
 630         if (pvk_magic != MS_PVKMAGIC) {
 631             PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_BAD_MAGIC_NUMBER);
 632             return 0;
 633         }
 634     }
 635     /* Skip reserved */
 636     p += 4;
 637     /*
 638      * keytype =
 639      */ read_ledword(&p);
 640     is_encrypted = read_ledword(&p);
 641     *psaltlen = read_ledword(&p);
 642     *pkeylen = read_ledword(&p);
 643
 644     if (is_encrypted && !*psaltlen) {
 645         PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_INCONSISTENT_HEADER);
 646         return 0;
 647     }
 648
 649     *in = p;
 650     return 1;
 651 }
 652
 653 static int derive_pvk_key(unsigned char *key,
 654                           const unsigned char *salt, unsigned int saltlen,
 655                           const unsigned char *pass, int passlen)
 656 {
 657     EVP_MD_CTX mctx;
 658     int rv = 1;
 659     EVP_MD_CTX_init(&mctx);
 660     if (!EVP_DigestInit_ex(&mctx, EVP_sha1(), NULL)
 661         || !EVP_DigestUpdate(&mctx, salt, saltlen)
 662         || !EVP_DigestUpdate(&mctx, pass, passlen)
 663         || !EVP_DigestFinal_ex(&mctx, key, NULL))
 664         rv = 0;
 665
 666     EVP_MD_CTX_cleanup(&mctx);
 667     return rv;
 668 }
 669
 670 static EVP_PKEY *do_PVK_body(const unsigned char **in,
 671                              unsigned int saltlen, unsigned int keylen,
 672                              pem_password_cb *cb, void *u)
 673 {
 674     EVP_PKEY *ret = NULL;
 675     const unsigned char *p = *in;
 676     unsigned int magic;
 677     unsigned char *enctmp = NULL, *q;
 678     EVP_CIPHER_CTX cctx;
 679     EVP_CIPHER_CTX_init(&cctx);
 680     if (saltlen) {
 681         char psbuf[PEM_BUFSIZE];
 682         unsigned char keybuf[20];
 683         int enctmplen, inlen;
 684         if (cb)
 685             inlen = cb(psbuf, PEM_BUFSIZE, 0, u);
 686         else
 687             inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 0, u);
 688         if (inlen <= 0) {
 689             PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_PASSWORD_READ);
 690             return NULL;
 691         }
 692         enctmp = OPENSSL_malloc(keylen + 8);
 693         if (!enctmp) {
 694             PEMerr(PEM_F_DO_PVK_BODY, ERR_R_MALLOC_FAILURE);
 695             return NULL;
 696         }
 697         if (!derive_pvk_key(keybuf, p, saltlen,
 698                             (unsigned char *)psbuf, inlen))
 699             return NULL;
 700         p += saltlen;
 701         /* Copy BLOBHEADER across, decrypt rest */
 702         memcpy(enctmp, p, 8);
 703         p += 8;
 704         if (keylen < 8) {
 705             PEMerr(PEM_F_DO_PVK_BODY, PEM_R_PVK_TOO_SHORT);
 706             return NULL;
 707         }
 708         inlen = keylen - 8;
 709         q = enctmp + 8;
 710         if (!EVP_DecryptInit_ex(&cctx, EVP_rc4(), NULL, keybuf, NULL))
 711             goto err;
 712         if (!EVP_DecryptUpdate(&cctx, q, &enctmplen, p, inlen))
 713             goto err;
 714         if (!EVP_DecryptFinal_ex(&cctx, q + enctmplen, &enctmplen))
 715             goto err;
 716         magic = read_ledword((const unsigned char **)&q);
 717         if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
 718             q = enctmp + 8;
 719             memset(keybuf + 5, 0, 11);
 720             if (!EVP_DecryptInit_ex(&cctx, EVP_rc4(), NULL, keybuf, NULL))
 721                 goto err;
 722             OPENSSL_cleanse(keybuf, 20);
 723             if (!EVP_DecryptUpdate(&cctx, q, &enctmplen, p, inlen))
 724                 goto err;
 725             if (!EVP_DecryptFinal_ex(&cctx, q + enctmplen, &enctmplen))
 726                 goto err;
 727             magic = read_ledword((const unsigned char **)&q);
 728             if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
 729                 PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_DECRYPT);
 730                 goto err;
 731             }
 732         } else
 733             OPENSSL_cleanse(keybuf, 20);
 734         p = enctmp;
 735     }
 736
 737     ret = b2i_PrivateKey(&p, keylen);
 738  err:
 739     EVP_CIPHER_CTX_cleanup(&cctx);
 740     if (enctmp && saltlen)
 741         OPENSSL_free(enctmp);
 742     return ret;
 743 }
 744
 745 EVP_PKEY *b2i_PVK_bio(BIO *in, pem_password_cb *cb, void *u)
 746 {
 747     unsigned char pvk_hdr[24], *buf = NULL;
 748     const unsigned char *p;
 749     int buflen;
 750     EVP_PKEY *ret = NULL;
 751     unsigned int saltlen, keylen;
 752     if (BIO_read(in, pvk_hdr, 24) != 24) {
 753         PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
 754         return NULL;
 755     }
 756     p = pvk_hdr;
 757
 758     if (!do_PVK_header(&p, 24, 0, &saltlen, &keylen))
 759         return 0;
 760     buflen = (int)keylen + saltlen;
 761     buf = OPENSSL_malloc(buflen);
 762     if (!buf) {
 763         PEMerr(PEM_F_B2I_PVK_BIO, ERR_R_MALLOC_FAILURE);
 764         return 0;
 765     }
 766     p = buf;
 767     if (BIO_read(in, buf, buflen) != buflen) {
 768         PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
 769         goto err;
 770     }
 771     ret = do_PVK_body(&p, saltlen, keylen, cb, u);
 772
 773  err:
 774     OPENSSL_clear_free(buf, buflen);
 775     return ret;
 776 }
 777
 778 static int i2b_PVK(unsigned char **out, EVP_PKEY *pk, int enclevel,
 779                    pem_password_cb *cb, void *u)
 780 {
 781     int outlen = 24, pklen;
 782     unsigned char *p, *salt = NULL;
 783     EVP_CIPHER_CTX cctx;
 784     EVP_CIPHER_CTX_init(&cctx);
 785     if (enclevel)
 786         outlen += PVK_SALTLEN;
 787     pklen = do_i2b(NULL, pk, 0);
 788     if (pklen < 0)
 789         return -1;
 790     outlen += pklen;
 791     if (!out)
 792         return outlen;
 793     if (*out)
 794         p = *out;
 795     else {
 796         p = OPENSSL_malloc(outlen);
 797         if (!p) {
 798             PEMerr(PEM_F_I2B_PVK, ERR_R_MALLOC_FAILURE);
 799             return -1;
 800         }
 801         *out = p;
 802     }
 803
 804     write_ledword(&p, MS_PVKMAGIC);
 805     write_ledword(&p, 0);
 806     if (pk->type == EVP_PKEY_DSA)
 807         write_ledword(&p, MS_KEYTYPE_SIGN);
 808     else
 809         write_ledword(&p, MS_KEYTYPE_KEYX);
 810     write_ledword(&p, enclevel ? 1 : 0);
 811     write_ledword(&p, enclevel ? PVK_SALTLEN : 0);
 812     write_ledword(&p, pklen);
 813     if (enclevel) {
 814         if (RAND_bytes(p, PVK_SALTLEN) <= 0)
 815             goto error;
 816         salt = p;
 817         p += PVK_SALTLEN;
 818     }
 819     do_i2b(&p, pk, 0);
 820     if (enclevel == 0)
 821         return outlen;
 822     else {
 823         char psbuf[PEM_BUFSIZE];
 824         unsigned char keybuf[20];
 825         int enctmplen, inlen;
 826         if (cb)
 827             inlen = cb(psbuf, PEM_BUFSIZE, 1, u);
 828         else
 829             inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 1, u);
 830         if (inlen <= 0) {
 831             PEMerr(PEM_F_I2B_PVK, PEM_R_BAD_PASSWORD_READ);
 832             goto error;
 833         }
 834         if (!derive_pvk_key(keybuf, salt, PVK_SALTLEN,
 835                             (unsigned char *)psbuf, inlen))
 836             goto error;
 837         if (enclevel == 1)
 838             memset(keybuf + 5, 0, 11);
 839         p = salt + PVK_SALTLEN + 8;
 840         if (!EVP_EncryptInit_ex(&cctx, EVP_rc4(), NULL, keybuf, NULL))
 841             goto error;
 842         OPENSSL_cleanse(keybuf, 20);
 843         if (!EVP_DecryptUpdate(&cctx, p, &enctmplen, p, pklen - 8))
 844             goto error;
 845         if (!EVP_DecryptFinal_ex(&cctx, p + enctmplen, &enctmplen))
 846             goto error;
 847     }
 848     EVP_CIPHER_CTX_cleanup(&cctx);
 849     return outlen;
 850
 851  error:
 852     EVP_CIPHER_CTX_cleanup(&cctx);
 853     return -1;
 854 }
 855
 856 int i2b_PVK_bio(BIO *out, EVP_PKEY *pk, int enclevel,
 857                 pem_password_cb *cb, void *u)
 858 {
 859     unsigned char *tmp = NULL;
 860     int outlen, wrlen;
 861     outlen = i2b_PVK(&tmp, pk, enclevel, cb, u);
 862     if (outlen < 0)
 863         return -1;
 864     wrlen = BIO_write(out, tmp, outlen);
 865     OPENSSL_free(tmp);
 866     if (wrlen == outlen) {
 867         PEMerr(PEM_F_I2B_PVK_BIO, PEM_R_BIO_WRITE_FAILURE);
 868         return outlen;
 869     }
 870     return -1;
 871 }
 872
 873 # endif
 874
 875 #endif