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 "internal/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     OPENSSL_free(buf);
 289     return ret;
 290 }
 291
 292 static EVP_PKEY *b2i_dss(const unsigned char **in, unsigned int length,
 293                          unsigned int bitlen, int ispub)
 294 {
 295     const unsigned char *p = *in;
 296     EVP_PKEY *ret = NULL;
 297     DSA *dsa = NULL;
 298     BN_CTX *ctx = NULL;
 299     unsigned int nbyte;
 300     nbyte = (bitlen + 7) >> 3;
 301
 302     dsa = DSA_new();
 303     ret = EVP_PKEY_new();
 304     if (!dsa || !ret)
 305         goto memerr;
 306     if (!read_lebn(&p, nbyte, &dsa->p))
 307         goto memerr;
 308     if (!read_lebn(&p, 20, &dsa->q))
 309         goto memerr;
 310     if (!read_lebn(&p, nbyte, &dsa->g))
 311         goto memerr;
 312     if (ispub) {
 313         if (!read_lebn(&p, nbyte, &dsa->pub_key))
 314             goto memerr;
 315     } else {
 316         if (!read_lebn(&p, 20, &dsa->priv_key))
 317             goto memerr;
 318         /* Calculate public key */
 319         if ((dsa->pub_key = BN_new()) == NULL)
 320             goto memerr;
 321         if ((ctx = BN_CTX_new()) == NULL)
 322             goto memerr;
 323
 324         if (!BN_mod_exp(dsa->pub_key, dsa->g, dsa->priv_key, dsa->p, ctx))
 325             goto memerr;
 326         BN_CTX_free(ctx);
 327     }
 328
 329     EVP_PKEY_set1_DSA(ret, dsa);
 330     DSA_free(dsa);
 331     *in = p;
 332     return ret;
 333
 334  memerr:
 335     PEMerr(PEM_F_B2I_DSS, ERR_R_MALLOC_FAILURE);
 336     DSA_free(dsa);
 337     EVP_PKEY_free(ret);
 338     BN_CTX_free(ctx);
 339     return NULL;
 340 }
 341
 342 static EVP_PKEY *b2i_rsa(const unsigned char **in, unsigned int length,
 343                          unsigned int bitlen, int ispub)
 344 {
 345     const unsigned char *p = *in;
 346     EVP_PKEY *ret = NULL;
 347     RSA *rsa = NULL;
 348     unsigned int nbyte, hnbyte;
 349     nbyte = (bitlen + 7) >> 3;
 350     hnbyte = (bitlen + 15) >> 4;
 351     rsa = RSA_new();
 352     ret = EVP_PKEY_new();
 353     if (!rsa || !ret)
 354         goto memerr;
 355     rsa->e = BN_new();
 356     if (!rsa->e)
 357         goto memerr;
 358     if (!BN_set_word(rsa->e, read_ledword(&p)))
 359         goto memerr;
 360     if (!read_lebn(&p, nbyte, &rsa->n))
 361         goto memerr;
 362     if (!ispub) {
 363         if (!read_lebn(&p, hnbyte, &rsa->p))
 364             goto memerr;
 365         if (!read_lebn(&p, hnbyte, &rsa->q))
 366             goto memerr;
 367         if (!read_lebn(&p, hnbyte, &rsa->dmp1))
 368             goto memerr;
 369         if (!read_lebn(&p, hnbyte, &rsa->dmq1))
 370             goto memerr;
 371         if (!read_lebn(&p, hnbyte, &rsa->iqmp))
 372             goto memerr;
 373         if (!read_lebn(&p, nbyte, &rsa->d))
 374             goto memerr;
 375     }
 376
 377     EVP_PKEY_set1_RSA(ret, rsa);
 378     RSA_free(rsa);
 379     *in = p;
 380     return ret;
 381  memerr:
 382     PEMerr(PEM_F_B2I_RSA, ERR_R_MALLOC_FAILURE);
 383     RSA_free(rsa);
 384     EVP_PKEY_free(ret);
 385     return NULL;
 386 }
 387
 388 EVP_PKEY *b2i_PrivateKey(const unsigned char **in, long length)
 389 {
 390     return do_b2i(in, length, 0);
 391 }
 392
 393 EVP_PKEY *b2i_PublicKey(const unsigned char **in, long length)
 394 {
 395     return do_b2i(in, length, 1);
 396 }
 397
 398 EVP_PKEY *b2i_PrivateKey_bio(BIO *in)
 399 {
 400     return do_b2i_bio(in, 0);
 401 }
 402
 403 EVP_PKEY *b2i_PublicKey_bio(BIO *in)
 404 {
 405     return do_b2i_bio(in, 1);
 406 }
 407
 408 static void write_ledword(unsigned char **out, unsigned int dw)
 409 {
 410     unsigned char *p = *out;
 411     *p++ = dw & 0xff;
 412     *p++ = (dw >> 8) & 0xff;
 413     *p++ = (dw >> 16) & 0xff;
 414     *p++ = (dw >> 24) & 0xff;
 415     *out = p;
 416 }
 417
 418 static void write_lebn(unsigned char **out, const BIGNUM *bn, int len)
 419 {
 420     int nb, i;
 421     unsigned char *p = *out, *q, c;
 422     nb = BN_num_bytes(bn);
 423     BN_bn2bin(bn, p);
 424     q = p + nb - 1;
 425     /* In place byte order reversal */
 426     for (i = 0; i < nb / 2; i++) {
 427         c = *p;
 428         *p++ = *q;
 429         *q-- = c;
 430     }
 431     *out += nb;
 432     /* Pad with zeroes if we have to */
 433     if (len > 0) {
 434         len -= nb;
 435         if (len > 0) {
 436             memset(*out, 0, len);
 437             *out += len;
 438         }
 439     }
 440 }
 441
 442 static int check_bitlen_rsa(RSA *rsa, int ispub, unsigned int *magic);
 443 static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *magic);
 444
 445 static void write_rsa(unsigned char **out, RSA *rsa, int ispub);
 446 static void write_dsa(unsigned char **out, DSA *dsa, int ispub);
 447
 448 static int do_i2b(unsigned char **out, EVP_PKEY *pk, int ispub)
 449 {
 450     unsigned char *p;
 451     unsigned int bitlen, magic = 0, keyalg;
 452     int outlen, noinc = 0;
 453     if (pk->type == EVP_PKEY_DSA) {
 454         bitlen = check_bitlen_dsa(pk->pkey.dsa, ispub, &magic);
 455         keyalg = MS_KEYALG_DSS_SIGN;
 456     } else if (pk->type == EVP_PKEY_RSA) {
 457         bitlen = check_bitlen_rsa(pk->pkey.rsa, ispub, &magic);
 458         keyalg = MS_KEYALG_RSA_KEYX;
 459     } else
 460         return -1;
 461     if (bitlen == 0)
 462         return -1;
 463     outlen = 16 + blob_length(bitlen,
 464                               keyalg == MS_KEYALG_DSS_SIGN ? 1 : 0, ispub);
 465     if (out == NULL)
 466         return outlen;
 467     if (*out)
 468         p = *out;
 469     else {
 470         p = OPENSSL_malloc(outlen);
 471         if (!p)
 472             return -1;
 473         *out = p;
 474         noinc = 1;
 475     }
 476     if (ispub)
 477         *p++ = MS_PUBLICKEYBLOB;
 478     else
 479         *p++ = MS_PRIVATEKEYBLOB;
 480     *p++ = 0x2;
 481     *p++ = 0;
 482     *p++ = 0;
 483     write_ledword(&p, keyalg);
 484     write_ledword(&p, magic);
 485     write_ledword(&p, bitlen);
 486     if (keyalg == MS_KEYALG_DSS_SIGN)
 487         write_dsa(&p, pk->pkey.dsa, ispub);
 488     else
 489         write_rsa(&p, pk->pkey.rsa, ispub);
 490     if (!noinc)
 491         *out += outlen;
 492     return outlen;
 493 }
 494
 495 static int do_i2b_bio(BIO *out, EVP_PKEY *pk, int ispub)
 496 {
 497     unsigned char *tmp = NULL;
 498     int outlen, wrlen;
 499     outlen = do_i2b(&tmp, pk, ispub);
 500     if (outlen < 0)
 501         return -1;
 502     wrlen = BIO_write(out, tmp, outlen);
 503     OPENSSL_free(tmp);
 504     if (wrlen == outlen)
 505         return outlen;
 506     return -1;
 507 }
 508
 509 static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *pmagic)
 510 {
 511     int bitlen;
 512     bitlen = BN_num_bits(dsa->p);
 513     if ((bitlen & 7) || (BN_num_bits(dsa->q) != 160)
 514         || (BN_num_bits(dsa->g) > bitlen))
 515         goto badkey;
 516     if (ispub) {
 517         if (BN_num_bits(dsa->pub_key) > bitlen)
 518             goto badkey;
 519         *pmagic = MS_DSS1MAGIC;
 520     } else {
 521         if (BN_num_bits(dsa->priv_key) > 160)
 522             goto badkey;
 523         *pmagic = MS_DSS2MAGIC;
 524     }
 525
 526     return bitlen;
 527  badkey:
 528     PEMerr(PEM_F_CHECK_BITLEN_DSA, PEM_R_UNSUPPORTED_KEY_COMPONENTS);
 529     return 0;
 530 }
 531
 532 static int check_bitlen_rsa(RSA *rsa, int ispub, unsigned int *pmagic)
 533 {
 534     int nbyte, hnbyte, bitlen;
 535     if (BN_num_bits(rsa->e) > 32)
 536         goto badkey;
 537     bitlen = BN_num_bits(rsa->n);
 538     nbyte = BN_num_bytes(rsa->n);
 539     hnbyte = (BN_num_bits(rsa->n) + 15) >> 4;
 540     if (ispub) {
 541         *pmagic = MS_RSA1MAGIC;
 542         return bitlen;
 543     } else {
 544         *pmagic = MS_RSA2MAGIC;
 545         /*
 546          * For private key each component must fit within nbyte or hnbyte.
 547          */
 548         if (BN_num_bytes(rsa->d) > nbyte)
 549             goto badkey;
 550         if ((BN_num_bytes(rsa->iqmp) > hnbyte)
 551             || (BN_num_bytes(rsa->p) > hnbyte)
 552             || (BN_num_bytes(rsa->q) > hnbyte)
 553             || (BN_num_bytes(rsa->dmp1) > hnbyte)
 554             || (BN_num_bytes(rsa->dmq1) > hnbyte))
 555             goto badkey;
 556     }
 557     return bitlen;
 558  badkey:
 559     PEMerr(PEM_F_CHECK_BITLEN_RSA, PEM_R_UNSUPPORTED_KEY_COMPONENTS);
 560     return 0;
 561 }
 562
 563 static void write_rsa(unsigned char **out, RSA *rsa, int ispub)
 564 {
 565     int nbyte, hnbyte;
 566     nbyte = BN_num_bytes(rsa->n);
 567     hnbyte = (BN_num_bits(rsa->n) + 15) >> 4;
 568     write_lebn(out, rsa->e, 4);
 569     write_lebn(out, rsa->n, -1);
 570     if (ispub)
 571         return;
 572     write_lebn(out, rsa->p, hnbyte);
 573     write_lebn(out, rsa->q, hnbyte);
 574     write_lebn(out, rsa->dmp1, hnbyte);
 575     write_lebn(out, rsa->dmq1, hnbyte);
 576     write_lebn(out, rsa->iqmp, hnbyte);
 577     write_lebn(out, rsa->d, nbyte);
 578 }
 579
 580 static void write_dsa(unsigned char **out, DSA *dsa, int ispub)
 581 {
 582     int nbyte;
 583     nbyte = BN_num_bytes(dsa->p);
 584     write_lebn(out, dsa->p, nbyte);
 585     write_lebn(out, dsa->q, 20);
 586     write_lebn(out, dsa->g, nbyte);
 587     if (ispub)
 588         write_lebn(out, dsa->pub_key, nbyte);
 589     else
 590         write_lebn(out, dsa->priv_key, 20);
 591     /* Set "invalid" for seed structure values */
 592     memset(*out, 0xff, 24);
 593     *out += 24;
 594     return;
 595 }
 596
 597 int i2b_PrivateKey_bio(BIO *out, EVP_PKEY *pk)
 598 {
 599     return do_i2b_bio(out, pk, 0);
 600 }
 601
 602 int i2b_PublicKey_bio(BIO *out, EVP_PKEY *pk)
 603 {
 604     return do_i2b_bio(out, pk, 1);
 605 }
 606
 607 # ifndef OPENSSL_NO_RC4
 608
 609 static int do_PVK_header(const unsigned char **in, unsigned int length,
 610                          int skip_magic,
 611                          unsigned int *psaltlen, unsigned int *pkeylen)
 612 {
 613     const unsigned char *p = *in;
 614     unsigned int pvk_magic, is_encrypted;
 615     if (skip_magic) {
 616         if (length < 20) {
 617             PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
 618             return 0;
 619         }
 620         length -= 20;
 621     } else {
 622         if (length < 24) {
 623             PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
 624             return 0;
 625         }
 626         length -= 24;
 627         pvk_magic = read_ledword(&p);
 628         if (pvk_magic != MS_PVKMAGIC) {
 629             PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_BAD_MAGIC_NUMBER);
 630             return 0;
 631         }
 632     }
 633     /* Skip reserved */
 634     p += 4;
 635     /*
 636      * keytype =
 637      */ read_ledword(&p);
 638     is_encrypted = read_ledword(&p);
 639     *psaltlen = read_ledword(&p);
 640     *pkeylen = read_ledword(&p);
 641
 642     if (is_encrypted && !*psaltlen) {
 643         PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_INCONSISTENT_HEADER);
 644         return 0;
 645     }
 646
 647     *in = p;
 648     return 1;
 649 }
 650
 651 static int derive_pvk_key(unsigned char *key,
 652                           const unsigned char *salt, unsigned int saltlen,
 653                           const unsigned char *pass, int passlen)
 654 {
 655     EVP_MD_CTX mctx;
 656     int rv = 1;
 657     EVP_MD_CTX_init(&mctx);
 658     if (!EVP_DigestInit_ex(&mctx, EVP_sha1(), NULL)
 659         || !EVP_DigestUpdate(&mctx, salt, saltlen)
 660         || !EVP_DigestUpdate(&mctx, pass, passlen)
 661         || !EVP_DigestFinal_ex(&mctx, key, NULL))
 662         rv = 0;
 663
 664     EVP_MD_CTX_cleanup(&mctx);
 665     return rv;
 666 }
 667
 668 static EVP_PKEY *do_PVK_body(const unsigned char **in,
 669                              unsigned int saltlen, unsigned int keylen,
 670                              pem_password_cb *cb, void *u)
 671 {
 672     EVP_PKEY *ret = NULL;
 673     const unsigned char *p = *in;
 674     unsigned int magic;
 675     unsigned char *enctmp = NULL, *q;
 676
 677     EVP_CIPHER_CTX cctx;
 678     EVP_CIPHER_CTX_init(&cctx);
 679     if (saltlen) {
 680         char psbuf[PEM_BUFSIZE];
 681         unsigned char keybuf[20];
 682         int enctmplen, inlen;
 683         if (cb)
 684             inlen = cb(psbuf, PEM_BUFSIZE, 0, u);
 685         else
 686             inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 0, u);
 687         if (inlen <= 0) {
 688             PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_PASSWORD_READ);
 689             return NULL;
 690         }
 691         enctmp = OPENSSL_malloc(keylen + 8);
 692         if (!enctmp) {
 693             PEMerr(PEM_F_DO_PVK_BODY, ERR_R_MALLOC_FAILURE);
 694             return NULL;
 695         }
 696         if (!derive_pvk_key(keybuf, p, saltlen,
 697                             (unsigned char *)psbuf, inlen))
 698             return NULL;
 699         p += saltlen;
 700         /* Copy BLOBHEADER across, decrypt rest */
 701         memcpy(enctmp, p, 8);
 702         p += 8;
 703         if (keylen < 8) {
 704             PEMerr(PEM_F_DO_PVK_BODY, PEM_R_PVK_TOO_SHORT);
 705             return NULL;
 706         }
 707         inlen = keylen - 8;
 708         q = enctmp + 8;
 709         if (!EVP_DecryptInit_ex(&cctx, EVP_rc4(), NULL, keybuf, NULL))
 710             goto err;
 711         if (!EVP_DecryptUpdate(&cctx, q, &enctmplen, p, inlen))
 712             goto err;
 713         if (!EVP_DecryptFinal_ex(&cctx, q + enctmplen, &enctmplen))
 714             goto err;
 715         magic = read_ledword((const unsigned char **)&q);
 716         if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
 717             q = enctmp + 8;
 718             memset(keybuf + 5, 0, 11);
 719             if (!EVP_DecryptInit_ex(&cctx, EVP_rc4(), NULL, keybuf, NULL))
 720                 goto err;
 721             OPENSSL_cleanse(keybuf, 20);
 722             if (!EVP_DecryptUpdate(&cctx, q, &enctmplen, p, inlen))
 723                 goto err;
 724             if (!EVP_DecryptFinal_ex(&cctx, q + enctmplen, &enctmplen))
 725                 goto err;
 726             magic = read_ledword((const unsigned char **)&q);
 727             if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
 728                 PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_DECRYPT);
 729                 goto err;
 730             }
 731         } else
 732             OPENSSL_cleanse(keybuf, 20);
 733         p = enctmp;
 734     }
 735
 736     ret = b2i_PrivateKey(&p, keylen);
 737  err:
 738     EVP_CIPHER_CTX_cleanup(&cctx);
 739     OPENSSL_free(enctmp);
 740     return ret;
 741 }
 742
 743 EVP_PKEY *b2i_PVK_bio(BIO *in, pem_password_cb *cb, void *u)
 744 {
 745     unsigned char pvk_hdr[24], *buf = NULL;
 746     const unsigned char *p;
 747     int buflen;
 748     EVP_PKEY *ret = NULL;
 749     unsigned int saltlen, keylen;
 750     if (BIO_read(in, pvk_hdr, 24) != 24) {
 751         PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
 752         return NULL;
 753     }
 754     p = pvk_hdr;
 755
 756     if (!do_PVK_header(&p, 24, 0, &saltlen, &keylen))
 757         return 0;
 758     buflen = (int)keylen + saltlen;
 759     buf = OPENSSL_malloc(buflen);
 760     if (!buf) {
 761         PEMerr(PEM_F_B2I_PVK_BIO, ERR_R_MALLOC_FAILURE);
 762         return 0;
 763     }
 764     p = buf;
 765     if (BIO_read(in, buf, buflen) != buflen) {
 766         PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
 767         goto err;
 768     }
 769     ret = do_PVK_body(&p, saltlen, keylen, cb, u);
 770
 771  err:
 772     OPENSSL_clear_free(buf, buflen);
 773     return ret;
 774 }
 775
 776 static int i2b_PVK(unsigned char **out, EVP_PKEY *pk, int enclevel,
 777                    pem_password_cb *cb, void *u)
 778 {
 779     int outlen = 24, pklen;
 780     unsigned char *p, *salt = NULL;
 781     EVP_CIPHER_CTX cctx;
 782     EVP_CIPHER_CTX_init(&cctx);
 783     if (enclevel)
 784         outlen += PVK_SALTLEN;
 785     pklen = do_i2b(NULL, pk, 0);
 786     if (pklen < 0)
 787         return -1;
 788     outlen += pklen;
 789     if (!out)
 790         return outlen;
 791     if (*out)
 792         p = *out;
 793     else {
 794         p = OPENSSL_malloc(outlen);
 795         if (!p) {
 796             PEMerr(PEM_F_I2B_PVK, ERR_R_MALLOC_FAILURE);
 797             return -1;
 798         }
 799         *out = p;
 800     }
 801
 802     write_ledword(&p, MS_PVKMAGIC);
 803     write_ledword(&p, 0);
 804     if (pk->type == EVP_PKEY_DSA)
 805         write_ledword(&p, MS_KEYTYPE_SIGN);
 806     else
 807         write_ledword(&p, MS_KEYTYPE_KEYX);
 808     write_ledword(&p, enclevel ? 1 : 0);
 809     write_ledword(&p, enclevel ? PVK_SALTLEN : 0);
 810     write_ledword(&p, pklen);
 811     if (enclevel) {
 812         if (RAND_bytes(p, PVK_SALTLEN) <= 0)
 813             goto error;
 814         salt = p;
 815         p += PVK_SALTLEN;
 816     }
 817     do_i2b(&p, pk, 0);
 818     if (enclevel == 0)
 819         return outlen;
 820     else {
 821         char psbuf[PEM_BUFSIZE];
 822         unsigned char keybuf[20];
 823         int enctmplen, inlen;
 824         if (cb)
 825             inlen = cb(psbuf, PEM_BUFSIZE, 1, u);
 826         else
 827             inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 1, u);
 828         if (inlen <= 0) {
 829             PEMerr(PEM_F_I2B_PVK, PEM_R_BAD_PASSWORD_READ);
 830             goto error;
 831         }
 832         if (!derive_pvk_key(keybuf, salt, PVK_SALTLEN,
 833                             (unsigned char *)psbuf, inlen))
 834             goto error;
 835         if (enclevel == 1)
 836             memset(keybuf + 5, 0, 11);
 837         p = salt + PVK_SALTLEN + 8;
 838         if (!EVP_EncryptInit_ex(&cctx, EVP_rc4(), NULL, keybuf, NULL))
 839             goto error;
 840         OPENSSL_cleanse(keybuf, 20);
 841         if (!EVP_DecryptUpdate(&cctx, p, &enctmplen, p, pklen - 8))
 842             goto error;
 843         if (!EVP_DecryptFinal_ex(&cctx, p + enctmplen, &enctmplen))
 844             goto error;
 845     }
 846     EVP_CIPHER_CTX_cleanup(&cctx);
 847     return outlen;
 848
 849  error:
 850     EVP_CIPHER_CTX_cleanup(&cctx);
 851     return -1;
 852 }
 853
 854 int i2b_PVK_bio(BIO *out, EVP_PKEY *pk, int enclevel,
 855                 pem_password_cb *cb, void *u)
 856 {
 857     unsigned char *tmp = NULL;
 858     int outlen, wrlen;
 859     outlen = i2b_PVK(&tmp, pk, enclevel, cb, u);
 860     if (outlen < 0)
 861         return -1;
 862     wrlen = BIO_write(out, tmp, outlen);
 863     OPENSSL_free(tmp);
 864     if (wrlen == outlen) {
 865         PEMerr(PEM_F_I2B_PVK_BIO, PEM_R_BIO_WRITE_FAILURE);
 866         return outlen;
 867     }
 868     return -1;
 869 }
 870
 871 # endif
 872
 873 #endif