crypto/pem/pvkfmt.c

   1 /*
   2  * Copyright 2005-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /*
  11  * Support for PVK format keys and related structures (such a PUBLICKEYBLOB
  12  * and PRIVATEKEYBLOB).
  13  */
  14
  15 /*
  16  * DSA low level APIs are deprecated for public use, but still ok for
  17  * internal use.
  18  */
  19 #include "internal/deprecated.h"
  20
  21 #include "internal/cryptlib.h"
  22 #include <openssl/pem.h>
  23 #include "crypto/pem.h"
  24 #include <openssl/rand.h>
  25 #include <openssl/bn.h>
  26 #if !defined(OPENSSL_NO_RSA) && !defined(OPENSSL_NO_DSA)
  27 # include <openssl/dsa.h>
  28 # include <openssl/rsa.h>
  29
  30 /*
  31  * Utility function: read a DWORD (4 byte unsigned integer) in little endian
  32  * format
  33  */
  34
  35 static unsigned int read_ledword(const unsigned char **in)
  36 {
  37     const unsigned char *p = *in;
  38     unsigned int ret;
  39     ret = (unsigned int)*p++;
  40     ret |= (unsigned int)*p++ << 8;
  41     ret |= (unsigned int)*p++ << 16;
  42     ret |= (unsigned int)*p++ << 24;
  43     *in = p;
  44     return ret;
  45 }
  46
  47 /*
  48  * Read a BIGNUM in little endian format. The docs say that this should take
  49  * up bitlen/8 bytes.
  50  */
  51
  52 static int read_lebn(const unsigned char **in, unsigned int nbyte, BIGNUM **r)
  53 {
  54     *r = BN_lebin2bn(*in, nbyte, NULL);
  55     if (*r == NULL)
  56         return 0;
  57     *in += nbyte;
  58     return 1;
  59 }
  60
  61 /* Convert private key blob to EVP_PKEY: RSA and DSA keys supported */
  62
  63 # define MS_PUBLICKEYBLOB        0x6
  64 # define MS_PRIVATEKEYBLOB       0x7
  65 # define MS_RSA1MAGIC            0x31415352L
  66 # define MS_RSA2MAGIC            0x32415352L
  67 # define MS_DSS1MAGIC            0x31535344L
  68 # define MS_DSS2MAGIC            0x32535344L
  69
  70 # define MS_KEYALG_RSA_KEYX      0xa400
  71 # define MS_KEYALG_DSS_SIGN      0x2200
  72
  73 # define MS_KEYTYPE_KEYX         0x1
  74 # define MS_KEYTYPE_SIGN         0x2
  75
  76 /* Maximum length of a blob after header */
  77 # define BLOB_MAX_LENGTH          102400
  78
  79 /* The PVK file magic number: seems to spell out "bobsfile", who is Bob? */
  80 # define MS_PVKMAGIC             0xb0b5f11eL
  81 /* Salt length for PVK files */
  82 # define PVK_SALTLEN             0x10
  83 /* Maximum length in PVK header */
  84 # define PVK_MAX_KEYLEN          102400
  85 /* Maximum salt length */
  86 # define PVK_MAX_SALTLEN         10240
  87
  88 static EVP_PKEY *b2i_rsa(const unsigned char **in,
  89                          unsigned int bitlen, int ispub);
  90 static EVP_PKEY *b2i_dss(const unsigned char **in,
  91                          unsigned int bitlen, int ispub);
  92
  93 int ossl_do_blob_header(const unsigned char **in, unsigned int length,
  94                         unsigned int *pmagic, unsigned int *pbitlen,
  95                         int *pisdss, int *pispub)
  96 {
  97     const unsigned char *p = *in;
  98     if (length < 16)
  99         return 0;
 100     /* bType */
 101     if (*p == MS_PUBLICKEYBLOB) {
 102         if (*pispub == 0) {
 103             PEMerr(PEM_F_OSSL_DO_BLOB_HEADER, PEM_R_EXPECTING_PRIVATE_KEY_BLOB);
 104             return 0;
 105         }
 106         *pispub = 1;
 107     } else if (*p == MS_PRIVATEKEYBLOB) {
 108         if (*pispub == 1) {
 109             PEMerr(PEM_F_OSSL_DO_BLOB_HEADER, PEM_R_EXPECTING_PUBLIC_KEY_BLOB);
 110             return 0;
 111         }
 112         *pispub = 0;
 113     } else
 114         return 0;
 115     p++;
 116     /* Version */
 117     if (*p++ != 0x2) {
 118         PEMerr(PEM_F_OSSL_DO_BLOB_HEADER, PEM_R_BAD_VERSION_NUMBER);
 119         return 0;
 120     }
 121     /* Ignore reserved, aiKeyAlg */
 122     p += 6;
 123     *pmagic = read_ledword(&p);
 124     *pbitlen = read_ledword(&p);
 125     *pisdss = 0;
 126     switch (*pmagic) {
 127
 128     case MS_DSS1MAGIC:
 129         *pisdss = 1;
 130         /* fall thru */
 131     case MS_RSA1MAGIC:
 132         if (*pispub == 0) {
 133             PEMerr(PEM_F_OSSL_DO_BLOB_HEADER, PEM_R_EXPECTING_PRIVATE_KEY_BLOB);
 134             return 0;
 135         }
 136         break;
 137
 138     case MS_DSS2MAGIC:
 139         *pisdss = 1;
 140         /* fall thru */
 141     case MS_RSA2MAGIC:
 142         if (*pispub == 1) {
 143             PEMerr(PEM_F_OSSL_DO_BLOB_HEADER, PEM_R_EXPECTING_PUBLIC_KEY_BLOB);
 144             return 0;
 145         }
 146         break;
 147
 148     default:
 149         PEMerr(PEM_F_OSSL_DO_BLOB_HEADER, PEM_R_BAD_MAGIC_NUMBER);
 150         return -1;
 151     }
 152     *in = p;
 153     return 1;
 154 }
 155
 156 static unsigned int blob_length(unsigned bitlen, int isdss, int ispub)
 157 {
 158     unsigned int nbyte, hnbyte;
 159     nbyte = (bitlen + 7) >> 3;
 160     hnbyte = (bitlen + 15) >> 4;
 161     if (isdss) {
 162
 163         /*
 164          * Expected length: 20 for q + 3 components bitlen each + 24 for seed
 165          * structure.
 166          */
 167         if (ispub)
 168             return 44 + 3 * nbyte;
 169         /*
 170          * Expected length: 20 for q, priv, 2 bitlen components + 24 for seed
 171          * structure.
 172          */
 173         else
 174             return 64 + 2 * nbyte;
 175     } else {
 176         /* Expected length: 4 for 'e' + 'n' */
 177         if (ispub)
 178             return 4 + nbyte;
 179         else
 180             /*
 181              * Expected length: 4 for 'e' and 7 other components. 2
 182              * components are bitlen size, 5 are bitlen/2
 183              */
 184             return 4 + 2 * nbyte + 5 * hnbyte;
 185     }
 186
 187 }
 188
 189 EVP_PKEY *ossl_b2i(const unsigned char **in, unsigned int length, int *ispub)
 190 {
 191     const unsigned char *p = *in;
 192     unsigned int bitlen, magic;
 193     int isdss;
 194     if (ossl_do_blob_header(&p, length, &magic, &bitlen, &isdss, ispub) <= 0) {
 195         PEMerr(0, PEM_R_KEYBLOB_HEADER_PARSE_ERROR);
 196         return NULL;
 197     }
 198     length -= 16;
 199     if (length < blob_length(bitlen, isdss, *ispub)) {
 200         PEMerr(0, PEM_R_KEYBLOB_TOO_SHORT);
 201         return NULL;
 202     }
 203     if (isdss)
 204         return b2i_dss(&p, bitlen, *ispub);
 205     else
 206         return b2i_rsa(&p, bitlen, *ispub);
 207 }
 208
 209 EVP_PKEY *ossl_b2i_bio(BIO *in, int *ispub)
 210 {
 211     const unsigned char *p;
 212     unsigned char hdr_buf[16], *buf = NULL;
 213     unsigned int bitlen, magic, length;
 214     int isdss;
 215     EVP_PKEY *ret = NULL;
 216     if (BIO_read(in, hdr_buf, 16) != 16) {
 217         PEMerr(0, PEM_R_KEYBLOB_TOO_SHORT);
 218         return NULL;
 219     }
 220     p = hdr_buf;
 221     if (ossl_do_blob_header(&p, 16, &magic, &bitlen, &isdss, ispub) <= 0)
 222         return NULL;
 223
 224     length = blob_length(bitlen, isdss, *ispub);
 225     if (length > BLOB_MAX_LENGTH) {
 226         PEMerr(0, PEM_R_HEADER_TOO_LONG);
 227         return NULL;
 228     }
 229     buf = OPENSSL_malloc(length);
 230     if (buf == NULL) {
 231         PEMerr(0, ERR_R_MALLOC_FAILURE);
 232         goto err;
 233     }
 234     p = buf;
 235     if (BIO_read(in, buf, length) != (int)length) {
 236         PEMerr(0, PEM_R_KEYBLOB_TOO_SHORT);
 237         goto err;
 238     }
 239
 240     if (isdss)
 241         ret = b2i_dss(&p, bitlen, *ispub);
 242     else
 243         ret = b2i_rsa(&p, bitlen, *ispub);
 244
 245  err:
 246     OPENSSL_free(buf);
 247     return ret;
 248 }
 249
 250 static EVP_PKEY *b2i_dss(const unsigned char **in,
 251                          unsigned int bitlen, int ispub)
 252 {
 253     const unsigned char *p = *in;
 254     EVP_PKEY *ret = NULL;
 255     DSA *dsa = NULL;
 256     BN_CTX *ctx = NULL;
 257     unsigned int nbyte;
 258     BIGNUM *pbn = NULL, *qbn = NULL, *gbn = NULL, *priv_key = NULL;
 259     BIGNUM *pub_key = NULL;
 260
 261     nbyte = (bitlen + 7) >> 3;
 262
 263     dsa = DSA_new();
 264     ret = EVP_PKEY_new();
 265     if (dsa == NULL || ret == NULL)
 266         goto memerr;
 267     if (!read_lebn(&p, nbyte, &pbn))
 268         goto memerr;
 269
 270     if (!read_lebn(&p, 20, &qbn))
 271         goto memerr;
 272
 273     if (!read_lebn(&p, nbyte, &gbn))
 274         goto memerr;
 275
 276     if (ispub) {
 277         if (!read_lebn(&p, nbyte, &pub_key))
 278             goto memerr;
 279     } else {
 280         if (!read_lebn(&p, 20, &priv_key))
 281             goto memerr;
 282
 283         /* Set constant time flag before public key calculation */
 284         BN_set_flags(priv_key, BN_FLG_CONSTTIME);
 285
 286         /* Calculate public key */
 287         pub_key = BN_new();
 288         if (pub_key == NULL)
 289             goto memerr;
 290         if ((ctx = BN_CTX_new()) == NULL)
 291             goto memerr;
 292
 293         if (!BN_mod_exp(pub_key, gbn, priv_key, pbn, ctx))
 294             goto memerr;
 295
 296         BN_CTX_free(ctx);
 297         ctx = NULL;
 298     }
 299     if (!DSA_set0_pqg(dsa, pbn, qbn, gbn))
 300         goto memerr;
 301     pbn = qbn = gbn = NULL;
 302     if (!DSA_set0_key(dsa, pub_key, priv_key))
 303         goto memerr;
 304     pub_key = priv_key = NULL;
 305
 306     if (!EVP_PKEY_set1_DSA(ret, dsa))
 307         goto memerr;
 308     DSA_free(dsa);
 309     *in = p;
 310     return ret;
 311
 312  memerr:
 313     PEMerr(PEM_F_B2I_DSS, ERR_R_MALLOC_FAILURE);
 314     DSA_free(dsa);
 315     BN_free(pbn);
 316     BN_free(qbn);
 317     BN_free(gbn);
 318     BN_free(pub_key);
 319     BN_free(priv_key);
 320     EVP_PKEY_free(ret);
 321     BN_CTX_free(ctx);
 322     return NULL;
 323 }
 324
 325 static EVP_PKEY *b2i_rsa(const unsigned char **in,
 326                          unsigned int bitlen, int ispub)
 327 {
 328     const unsigned char *pin = *in;
 329     EVP_PKEY *ret = NULL;
 330     BIGNUM *e = NULL, *n = NULL, *d = NULL;
 331     BIGNUM *p = NULL, *q = NULL, *dmp1 = NULL, *dmq1 = NULL, *iqmp = NULL;
 332     RSA *rsa = NULL;
 333     unsigned int nbyte, hnbyte;
 334     nbyte = (bitlen + 7) >> 3;
 335     hnbyte = (bitlen + 15) >> 4;
 336     rsa = RSA_new();
 337     ret = EVP_PKEY_new();
 338     if (rsa == NULL || ret == NULL)
 339         goto memerr;
 340     e = BN_new();
 341     if (e == NULL)
 342         goto memerr;
 343     if (!BN_set_word(e, read_ledword(&pin)))
 344         goto memerr;
 345     if (!read_lebn(&pin, nbyte, &n))
 346         goto memerr;
 347     if (!ispub) {
 348         if (!read_lebn(&pin, hnbyte, &p))
 349             goto memerr;
 350         if (!read_lebn(&pin, hnbyte, &q))
 351             goto memerr;
 352         if (!read_lebn(&pin, hnbyte, &dmp1))
 353             goto memerr;
 354         if (!read_lebn(&pin, hnbyte, &dmq1))
 355             goto memerr;
 356         if (!read_lebn(&pin, hnbyte, &iqmp))
 357             goto memerr;
 358         if (!read_lebn(&pin, nbyte, &d))
 359             goto memerr;
 360         if (!RSA_set0_factors(rsa, p, q))
 361             goto memerr;
 362         p = q = NULL;
 363         if (!RSA_set0_crt_params(rsa, dmp1, dmq1, iqmp))
 364             goto memerr;
 365         dmp1 = dmq1 = iqmp = NULL;
 366     }
 367     if (!RSA_set0_key(rsa, n, e, d))
 368         goto memerr;
 369     n = e = d = NULL;
 370
 371     if (!EVP_PKEY_set1_RSA(ret, rsa))
 372         goto memerr;
 373     RSA_free(rsa);
 374     *in = pin;
 375     return ret;
 376  memerr:
 377     PEMerr(PEM_F_B2I_RSA, ERR_R_MALLOC_FAILURE);
 378     BN_free(e);
 379     BN_free(n);
 380     BN_free(p);
 381     BN_free(q);
 382     BN_free(dmp1);
 383     BN_free(dmq1);
 384     BN_free(iqmp);
 385     BN_free(d);
 386     RSA_free(rsa);
 387     EVP_PKEY_free(ret);
 388     return NULL;
 389 }
 390
 391 EVP_PKEY *b2i_PrivateKey(const unsigned char **in, long length)
 392 {
 393     int ispub = 0;
 394
 395     return ossl_b2i(in, length, &ispub);
 396 }
 397
 398 EVP_PKEY *b2i_PublicKey(const unsigned char **in, long length)
 399 {
 400     int ispub = 1;
 401
 402     return ossl_b2i(in, length, &ispub);
 403 }
 404
 405 EVP_PKEY *b2i_PrivateKey_bio(BIO *in)
 406 {
 407     int ispub = 0;
 408
 409     return ossl_b2i_bio(in, &ispub);
 410 }
 411
 412 EVP_PKEY *b2i_PublicKey_bio(BIO *in)
 413 {
 414     int ispub = 1;
 415
 416     return ossl_b2i_bio(in, &ispub);
 417 }
 418
 419 static void write_ledword(unsigned char **out, unsigned int dw)
 420 {
 421     unsigned char *p = *out;
 422     *p++ = dw & 0xff;
 423     *p++ = (dw >> 8) & 0xff;
 424     *p++ = (dw >> 16) & 0xff;
 425     *p++ = (dw >> 24) & 0xff;
 426     *out = p;
 427 }
 428
 429 static void write_lebn(unsigned char **out, const BIGNUM *bn, int len)
 430 {
 431     BN_bn2lebinpad(bn, *out, len);
 432     *out += len;
 433 }
 434
 435 static int check_bitlen_rsa(RSA *rsa, int ispub, unsigned int *magic);
 436 static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *magic);
 437
 438 static void write_rsa(unsigned char **out, RSA *rsa, int ispub);
 439 static void write_dsa(unsigned char **out, DSA *dsa, int ispub);
 440
 441 static int do_i2b(unsigned char **out, const EVP_PKEY *pk, int ispub)
 442 {
 443     unsigned char *p;
 444     unsigned int bitlen, magic = 0, keyalg;
 445     int outlen, noinc = 0;
 446     int pktype = EVP_PKEY_id(pk);
 447     if (pktype == EVP_PKEY_DSA) {
 448         bitlen = check_bitlen_dsa(EVP_PKEY_get0_DSA(pk), ispub, &magic);
 449         keyalg = MS_KEYALG_DSS_SIGN;
 450     } else if (pktype == EVP_PKEY_RSA) {
 451         bitlen = check_bitlen_rsa(EVP_PKEY_get0_RSA(pk), ispub, &magic);
 452         keyalg = MS_KEYALG_RSA_KEYX;
 453     } else
 454         return -1;
 455     if (bitlen == 0)
 456         return -1;
 457     outlen = 16 + blob_length(bitlen,
 458                               keyalg == MS_KEYALG_DSS_SIGN ? 1 : 0, ispub);
 459     if (out == NULL)
 460         return outlen;
 461     if (*out)
 462         p = *out;
 463     else {
 464         if ((p = OPENSSL_malloc(outlen)) == NULL) {
 465             PEMerr(PEM_F_DO_I2B, ERR_R_MALLOC_FAILURE);
 466             return -1;
 467         }
 468         *out = p;
 469         noinc = 1;
 470     }
 471     if (ispub)
 472         *p++ = MS_PUBLICKEYBLOB;
 473     else
 474         *p++ = MS_PRIVATEKEYBLOB;
 475     *p++ = 0x2;
 476     *p++ = 0;
 477     *p++ = 0;
 478     write_ledword(&p, keyalg);
 479     write_ledword(&p, magic);
 480     write_ledword(&p, bitlen);
 481     if (keyalg == MS_KEYALG_DSS_SIGN)
 482         write_dsa(&p, EVP_PKEY_get0_DSA(pk), ispub);
 483     else
 484         write_rsa(&p, EVP_PKEY_get0_RSA(pk), ispub);
 485     if (!noinc)
 486         *out += outlen;
 487     return outlen;
 488 }
 489
 490 static int do_i2b_bio(BIO *out, const EVP_PKEY *pk, int ispub)
 491 {
 492     unsigned char *tmp = NULL;
 493     int outlen, wrlen;
 494     outlen = do_i2b(&tmp, pk, ispub);
 495     if (outlen < 0)
 496         return -1;
 497     wrlen = BIO_write(out, tmp, outlen);
 498     OPENSSL_free(tmp);
 499     if (wrlen == outlen)
 500         return outlen;
 501     return -1;
 502 }
 503
 504 static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *pmagic)
 505 {
 506     int bitlen;
 507     const BIGNUM *p = NULL, *q = NULL, *g = NULL;
 508     const BIGNUM *pub_key = NULL, *priv_key = NULL;
 509
 510     DSA_get0_pqg(dsa, &p, &q, &g);
 511     DSA_get0_key(dsa, &pub_key, &priv_key);
 512     bitlen = BN_num_bits(p);
 513     if ((bitlen & 7) || (BN_num_bits(q) != 160)
 514         || (BN_num_bits(g) > bitlen))
 515         goto badkey;
 516     if (ispub) {
 517         if (BN_num_bits(pub_key) > bitlen)
 518             goto badkey;
 519         *pmagic = MS_DSS1MAGIC;
 520     } else {
 521         if (BN_num_bits(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     const BIGNUM *e;
 536
 537     RSA_get0_key(rsa, NULL, &e, NULL);
 538     if (BN_num_bits(e) > 32)
 539         goto badkey;
 540     bitlen = RSA_bits(rsa);
 541     nbyte = RSA_size(rsa);
 542     hnbyte = (bitlen + 15) >> 4;
 543     if (ispub) {
 544         *pmagic = MS_RSA1MAGIC;
 545         return bitlen;
 546     } else {
 547         const BIGNUM *d, *p, *q, *iqmp, *dmp1, *dmq1;
 548
 549         *pmagic = MS_RSA2MAGIC;
 550
 551         /*
 552          * For private key each component must fit within nbyte or hnbyte.
 553          */
 554         RSA_get0_key(rsa, NULL, NULL, &d);
 555         if (BN_num_bytes(d) > nbyte)
 556             goto badkey;
 557         RSA_get0_factors(rsa, &p, &q);
 558         RSA_get0_crt_params(rsa, &dmp1, &dmq1, &iqmp);
 559         if ((BN_num_bytes(iqmp) > hnbyte)
 560             || (BN_num_bytes(p) > hnbyte)
 561             || (BN_num_bytes(q) > hnbyte)
 562             || (BN_num_bytes(dmp1) > hnbyte)
 563             || (BN_num_bytes(dmq1) > hnbyte))
 564             goto badkey;
 565     }
 566     return bitlen;
 567  badkey:
 568     PEMerr(PEM_F_CHECK_BITLEN_RSA, PEM_R_UNSUPPORTED_KEY_COMPONENTS);
 569     return 0;
 570 }
 571
 572 static void write_rsa(unsigned char **out, RSA *rsa, int ispub)
 573 {
 574     int nbyte, hnbyte;
 575     const BIGNUM *n, *d, *e, *p, *q, *iqmp, *dmp1, *dmq1;
 576
 577     nbyte = RSA_size(rsa);
 578     hnbyte = (RSA_bits(rsa) + 15) >> 4;
 579     RSA_get0_key(rsa, &n, &e, &d);
 580     write_lebn(out, e, 4);
 581     write_lebn(out, n, nbyte);
 582     if (ispub)
 583         return;
 584     RSA_get0_factors(rsa, &p, &q);
 585     RSA_get0_crt_params(rsa, &dmp1, &dmq1, &iqmp);
 586     write_lebn(out, p, hnbyte);
 587     write_lebn(out, q, hnbyte);
 588     write_lebn(out, dmp1, hnbyte);
 589     write_lebn(out, dmq1, hnbyte);
 590     write_lebn(out, iqmp, hnbyte);
 591     write_lebn(out, d, nbyte);
 592 }
 593
 594 static void write_dsa(unsigned char **out, DSA *dsa, int ispub)
 595 {
 596     int nbyte;
 597     const BIGNUM *p = NULL, *q = NULL, *g = NULL;
 598     const BIGNUM *pub_key = NULL, *priv_key = NULL;
 599
 600     DSA_get0_pqg(dsa, &p, &q, &g);
 601     DSA_get0_key(dsa, &pub_key, &priv_key);
 602     nbyte = BN_num_bytes(p);
 603     write_lebn(out, p, nbyte);
 604     write_lebn(out, q, 20);
 605     write_lebn(out, g, nbyte);
 606     if (ispub)
 607         write_lebn(out, pub_key, nbyte);
 608     else
 609         write_lebn(out, priv_key, 20);
 610     /* Set "invalid" for seed structure values */
 611     memset(*out, 0xff, 24);
 612     *out += 24;
 613     return;
 614 }
 615
 616 int i2b_PrivateKey_bio(BIO *out, const EVP_PKEY *pk)
 617 {
 618     return do_i2b_bio(out, pk, 0);
 619 }
 620
 621 int i2b_PublicKey_bio(BIO *out, const EVP_PKEY *pk)
 622 {
 623     return do_i2b_bio(out, pk, 1);
 624 }
 625
 626 # ifndef OPENSSL_NO_RC4
 627
 628 int ossl_do_PVK_header(const unsigned char **in, unsigned int length,
 629                        int skip_magic,
 630                        unsigned int *psaltlen, unsigned int *pkeylen)
 631 {
 632     const unsigned char *p = *in;
 633     unsigned int pvk_magic, is_encrypted;
 634
 635     if (skip_magic) {
 636         if (length < 20) {
 637             PEMerr(PEM_F_OSSL_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
 638             return 0;
 639         }
 640     } else {
 641         if (length < 24) {
 642             PEMerr(PEM_F_OSSL_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
 643             return 0;
 644         }
 645         pvk_magic = read_ledword(&p);
 646         if (pvk_magic != MS_PVKMAGIC) {
 647             PEMerr(PEM_F_OSSL_DO_PVK_HEADER, PEM_R_BAD_MAGIC_NUMBER);
 648             return 0;
 649         }
 650     }
 651     /* Skip reserved */
 652     p += 4;
 653     /*
 654      * keytype =
 655      */ read_ledword(&p);
 656     is_encrypted = read_ledword(&p);
 657     *psaltlen = read_ledword(&p);
 658     *pkeylen = read_ledword(&p);
 659
 660     if (*pkeylen > PVK_MAX_KEYLEN || *psaltlen > PVK_MAX_SALTLEN)
 661         return 0;
 662
 663     if (is_encrypted && *psaltlen == 0) {
 664         PEMerr(PEM_F_OSSL_DO_PVK_HEADER, PEM_R_INCONSISTENT_HEADER);
 665         return 0;
 666     }
 667
 668     *in = p;
 669     return 1;
 670 }
 671
 672 static int derive_pvk_key(unsigned char *key,
 673                           const unsigned char *salt, unsigned int saltlen,
 674                           const unsigned char *pass, int passlen)
 675 {
 676     EVP_MD_CTX *mctx = EVP_MD_CTX_new();
 677     int rv = 1;
 678     if (mctx == NULL
 679         || !EVP_DigestInit_ex(mctx, EVP_sha1(), NULL)
 680         || !EVP_DigestUpdate(mctx, salt, saltlen)
 681         || !EVP_DigestUpdate(mctx, pass, passlen)
 682         || !EVP_DigestFinal_ex(mctx, key, NULL))
 683         rv = 0;
 684
 685     EVP_MD_CTX_free(mctx);
 686     return rv;
 687 }
 688
 689 static EVP_PKEY *do_PVK_body(const unsigned char **in,
 690                              unsigned int saltlen, unsigned int keylen,
 691                              pem_password_cb *cb, void *u)
 692 {
 693     EVP_PKEY *ret = NULL;
 694     const unsigned char *p = *in;
 695     unsigned int magic;
 696     unsigned char *enctmp = NULL, *q;
 697     unsigned char keybuf[20];
 698
 699     EVP_CIPHER_CTX *cctx = EVP_CIPHER_CTX_new();
 700     if (saltlen) {
 701         char psbuf[PEM_BUFSIZE];
 702         int enctmplen, inlen;
 703         if (cb)
 704             inlen = cb(psbuf, PEM_BUFSIZE, 0, u);
 705         else
 706             inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 0, u);
 707         if (inlen < 0) {
 708             PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_PASSWORD_READ);
 709             goto err;
 710         }
 711         enctmp = OPENSSL_malloc(keylen + 8);
 712         if (enctmp == NULL) {
 713             PEMerr(PEM_F_DO_PVK_BODY, ERR_R_MALLOC_FAILURE);
 714             goto err;
 715         }
 716         if (!derive_pvk_key(keybuf, p, saltlen,
 717                             (unsigned char *)psbuf, inlen))
 718             goto err;
 719         p += saltlen;
 720         /* Copy BLOBHEADER across, decrypt rest */
 721         memcpy(enctmp, p, 8);
 722         p += 8;
 723         if (keylen < 8) {
 724             PEMerr(PEM_F_DO_PVK_BODY, PEM_R_PVK_TOO_SHORT);
 725             goto err;
 726         }
 727         inlen = keylen - 8;
 728         q = enctmp + 8;
 729         if (!EVP_DecryptInit_ex(cctx, EVP_rc4(), NULL, keybuf, NULL))
 730             goto err;
 731         if (!EVP_DecryptUpdate(cctx, q, &enctmplen, p, inlen))
 732             goto err;
 733         if (!EVP_DecryptFinal_ex(cctx, q + enctmplen, &enctmplen))
 734             goto err;
 735         magic = read_ledword((const unsigned char **)&q);
 736         if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
 737             q = enctmp + 8;
 738             memset(keybuf + 5, 0, 11);
 739             if (!EVP_DecryptInit_ex(cctx, EVP_rc4(), NULL, keybuf, NULL))
 740                 goto err;
 741             if (!EVP_DecryptUpdate(cctx, q, &enctmplen, p, inlen))
 742                 goto err;
 743             if (!EVP_DecryptFinal_ex(cctx, q + enctmplen, &enctmplen))
 744                 goto err;
 745             magic = read_ledword((const unsigned char **)&q);
 746             if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
 747                 PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_DECRYPT);
 748                 goto err;
 749             }
 750         }
 751         p = enctmp;
 752     }
 753
 754     ret = b2i_PrivateKey(&p, keylen);
 755  err:
 756     EVP_CIPHER_CTX_free(cctx);
 757     if (enctmp != NULL) {
 758         OPENSSL_cleanse(keybuf, sizeof(keybuf));
 759         OPENSSL_free(enctmp);
 760     }
 761     return ret;
 762 }
 763
 764 EVP_PKEY *b2i_PVK_bio(BIO *in, pem_password_cb *cb, void *u)
 765 {
 766     unsigned char pvk_hdr[24], *buf = NULL;
 767     const unsigned char *p;
 768     int buflen;
 769     EVP_PKEY *ret = NULL;
 770     unsigned int saltlen, keylen;
 771     if (BIO_read(in, pvk_hdr, 24) != 24) {
 772         PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
 773         return NULL;
 774     }
 775     p = pvk_hdr;
 776
 777     if (!ossl_do_PVK_header(&p, 24, 0, &saltlen, &keylen))
 778         return 0;
 779     buflen = (int)keylen + saltlen;
 780     buf = OPENSSL_malloc(buflen);
 781     if (buf == NULL) {
 782         PEMerr(PEM_F_B2I_PVK_BIO, ERR_R_MALLOC_FAILURE);
 783         return 0;
 784     }
 785     p = buf;
 786     if (BIO_read(in, buf, buflen) != buflen) {
 787         PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
 788         goto err;
 789     }
 790     ret = do_PVK_body(&p, saltlen, keylen, cb, u);
 791
 792  err:
 793     OPENSSL_clear_free(buf, buflen);
 794     return ret;
 795 }
 796
 797 static int i2b_PVK(unsigned char **out, const EVP_PKEY *pk, int enclevel,
 798                    pem_password_cb *cb, void *u)
 799 {
 800     int outlen = 24, pklen;
 801     unsigned char *p = NULL, *start = NULL, *salt = NULL;
 802     EVP_CIPHER_CTX *cctx = NULL;
 803     if (enclevel)
 804         outlen += PVK_SALTLEN;
 805     pklen = do_i2b(NULL, pk, 0);
 806     if (pklen < 0)
 807         return -1;
 808     outlen += pklen;
 809     if (out == NULL)
 810         return outlen;
 811     if (*out != NULL) {
 812         p = *out;
 813     } else {
 814         start = p = OPENSSL_malloc(outlen);
 815         if (p == NULL) {
 816             PEMerr(PEM_F_I2B_PVK, ERR_R_MALLOC_FAILURE);
 817             return -1;
 818         }
 819     }
 820
 821     cctx = EVP_CIPHER_CTX_new();
 822     if (cctx == NULL)
 823         goto error;
 824
 825     write_ledword(&p, MS_PVKMAGIC);
 826     write_ledword(&p, 0);
 827     if (EVP_PKEY_id(pk) == EVP_PKEY_DSA)
 828         write_ledword(&p, MS_KEYTYPE_SIGN);
 829     else
 830         write_ledword(&p, MS_KEYTYPE_KEYX);
 831     write_ledword(&p, enclevel ? 1 : 0);
 832     write_ledword(&p, enclevel ? PVK_SALTLEN : 0);
 833     write_ledword(&p, pklen);
 834     if (enclevel) {
 835         if (RAND_bytes(p, PVK_SALTLEN) <= 0)
 836             goto error;
 837         salt = p;
 838         p += PVK_SALTLEN;
 839     }
 840     do_i2b(&p, pk, 0);
 841     if (enclevel != 0) {
 842         char psbuf[PEM_BUFSIZE];
 843         unsigned char keybuf[20];
 844         int enctmplen, inlen;
 845         if (cb)
 846             inlen = cb(psbuf, PEM_BUFSIZE, 1, u);
 847         else
 848             inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 1, u);
 849         if (inlen <= 0) {
 850             PEMerr(PEM_F_I2B_PVK, PEM_R_BAD_PASSWORD_READ);
 851             goto error;
 852         }
 853         if (!derive_pvk_key(keybuf, salt, PVK_SALTLEN,
 854                             (unsigned char *)psbuf, inlen))
 855             goto error;
 856         if (enclevel == 1)
 857             memset(keybuf + 5, 0, 11);
 858         p = salt + PVK_SALTLEN + 8;
 859         if (!EVP_EncryptInit_ex(cctx, EVP_rc4(), NULL, keybuf, NULL))
 860             goto error;
 861         OPENSSL_cleanse(keybuf, 20);
 862         if (!EVP_EncryptUpdate(cctx, p, &enctmplen, p, pklen - 8))
 863             goto error;
 864         if (!EVP_EncryptFinal_ex(cctx, p + enctmplen, &enctmplen))
 865             goto error;
 866     }
 867
 868     EVP_CIPHER_CTX_free(cctx);
 869
 870     if (*out == NULL)
 871         *out = start;
 872
 873     return outlen;
 874
 875  error:
 876     EVP_CIPHER_CTX_free(cctx);
 877     if (*out == NULL)
 878         OPENSSL_free(start);
 879     return -1;
 880 }
 881
 882 int i2b_PVK_bio(BIO *out, const EVP_PKEY *pk, int enclevel,
 883                 pem_password_cb *cb, void *u)
 884 {
 885     unsigned char *tmp = NULL;
 886     int outlen, wrlen;
 887     outlen = i2b_PVK(&tmp, pk, enclevel, cb, u);
 888     if (outlen < 0)
 889         return -1;
 890     wrlen = BIO_write(out, tmp, outlen);
 891     OPENSSL_free(tmp);
 892     if (wrlen == outlen) {
 893         return outlen;
 894     }
 895     PEMerr(PEM_F_I2B_PVK_BIO, PEM_R_BIO_WRITE_FAILURE);
 896     return -1;
 897 }
 898
 899 # endif
 900
 901 #endif