apps/enc.c

   1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   2  * All rights reserved.
   3  *
   4  * This package is an SSL implementation written
   5  * by Eric Young (eay@cryptsoft.com).
   6  * The implementation was written so as to conform with Netscapes SSL.
   7  *
   8  * This library is free for commercial and non-commercial use as long as
   9  * the following conditions are aheared to.  The following conditions
  10  * apply to all code found in this distribution, be it the RC4, RSA,
  11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  12  * included with this distribution is covered by the same copyright terms
  13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  14  *
  15  * Copyright remains Eric Young's, and as such any Copyright notices in
  16  * the code are not to be removed.
  17  * If this package is used in a product, Eric Young should be given attribution
  18  * as the author of the parts of the library used.
  19  * This can be in the form of a textual message at program startup or
  20  * in documentation (online or textual) provided with the package.
  21  *
  22  * Redistribution and use in source and binary forms, with or without
  23  * modification, are permitted provided that the following conditions
  24  * are met:
  25  * 1. Redistributions of source code must retain the copyright
  26  *    notice, this list of conditions and the following disclaimer.
  27  * 2. Redistributions in binary form must reproduce the above copyright
  28  *    notice, this list of conditions and the following disclaimer in the
  29  *    documentation and/or other materials provided with the distribution.
  30  * 3. All advertising materials mentioning features or use of this software
  31  *    must display the following acknowledgement:
  32  *    "This product includes cryptographic software written by
  33  *     Eric Young (eay@cryptsoft.com)"
  34  *    The word 'cryptographic' can be left out if the rouines from the library
  35  *    being used are not cryptographic related :-).
  36  * 4. If you include any Windows specific code (or a derivative thereof) from
  37  *    the apps directory (application code) you must include an acknowledgement:
  38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  50  * SUCH DAMAGE.
  51  *
  52  * The licence and distribution terms for any publically available version or
  53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  54  * copied and put under another distribution licence
  55  * [including the GNU Public Licence.]
  56  */
  57
  58 #include <stdio.h>
  59 #include <stdlib.h>
  60 #include <string.h>
  61 #include "apps.h"
  62 #include <openssl/bio.h>
  63 #include <openssl/err.h>
  64 #include <openssl/evp.h>
  65 #include <openssl/objects.h>
  66 #include <openssl/x509.h>
  67 #include <openssl/rand.h>
  68 #include <openssl/pem.h>
  69 #ifndef OPENSSL_NO_COMP
  70 # include <openssl/comp.h>
  71 #endif
  72 #include <ctype.h>
  73
  74 #undef SIZE
  75 #undef BSIZE
  76 #define SIZE    (512)
  77 #define BSIZE   (8*1024)
  78
  79 static int set_hex(char *in, unsigned char *out, int size);
  80 static void show_ciphers(const OBJ_NAME *name, void *bio_);
  81
  82 typedef enum OPTION_choice {
  83     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  84     OPT_E, OPT_IN, OPT_OUT, OPT_PASS, OPT_ENGINE, OPT_D, OPT_P, OPT_V,
  85     OPT_NOPAD, OPT_SALT, OPT_NOSALT, OPT_DEBUG, OPT_UPPER_P, OPT_UPPER_A,
  86     OPT_A, OPT_Z, OPT_BUFSIZE, OPT_K, OPT_KFILE, OPT_UPPER_K, OPT_NONE,
  87     OPT_UPPER_S, OPT_IV, OPT_MD, OPT_NON_FIPS_ALLOW, OPT_CIPHER
  88 } OPTION_CHOICE;
  89
  90 OPTIONS enc_options[] = {
  91     {"help", OPT_HELP, '-', "Display this summary"},
  92     {"in", OPT_IN, '<', "Input file"},
  93     {"out", OPT_OUT, '>', "Output file"},
  94     {"pass", OPT_PASS, 's', "Passphrase source"},
  95     {"e", OPT_E, '-', "Encrypt"},
  96     {"d", OPT_D, '-', "Decrypt"},
  97     {"p", OPT_P, '-', "Print the iv/key"},
  98     {"P", OPT_UPPER_P, '-', "Print the iv/key and exit"},
  99     {"v", OPT_V, '-'},
 100     {"nopad", OPT_NOPAD, '-', "Disable standard block padding"},
 101     {"salt", OPT_SALT, '-'},
 102     {"nosalt", OPT_NOSALT, '-'},
 103     {"debug", OPT_DEBUG, '-'},
 104     {"A", OPT_UPPER_A, '-'},
 105     {"a", OPT_A, '-', "base64 encode/decode, depending on encryption flag"},
 106     {"base64", OPT_A, '-', "Base64 output as a single line"},
 107     {"bufsize", OPT_BUFSIZE, 's', "Buffer size"},
 108     {"k", OPT_K, 's', "Passphrase"},
 109     {"kfile", OPT_KFILE, '<', "Fead passphrase from file"},
 110     {"K", OPT_UPPER_K, 's', "Raw key, in hex"},
 111     {"S", OPT_UPPER_S, 's', "Salt, in hex"},
 112     {"iv", OPT_IV, 's', "IV in hex"},
 113     {"md", OPT_MD, 's', "Use specified digest to create key from passphrase"},
 114     {"non-fips-allow", OPT_NON_FIPS_ALLOW, '-'},
 115     {"none", OPT_NONE, '-', "Don't encrypt"},
 116     {"", OPT_CIPHER, '-', "Any supported cipher"},
 117 #ifdef ZLIB
 118     {"z", OPT_Z, '-', "Use zlib as the 'encryption'"},
 119 #endif
 120 #ifndef OPENSSL_NO_ENGINE
 121     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
 122 #endif
 123     {NULL}
 124 };
 125
 126 int enc_main(int argc, char **argv)
 127 {
 128     static char buf[128];
 129     static const char magic[] = "Salted__";
 130     BIO *in = NULL, *out = NULL, *b64 = NULL, *benc = NULL, *rbio =
 131         NULL, *wbio = NULL;
 132     EVP_CIPHER_CTX *ctx = NULL;
 133     const EVP_CIPHER *cipher = NULL, *c;
 134     const EVP_MD *dgst = NULL;
 135     char *hkey = NULL, *hiv = NULL, *hsalt = NULL, *p;
 136     char *infile = NULL, *outfile = NULL, *prog;
 137     char *str = NULL, *passarg = NULL, *pass = NULL, *strbuf = NULL;
 138     char mbuf[sizeof magic - 1];
 139     OPTION_CHOICE o;
 140     int bsize = BSIZE, verbose = 0, debug = 0, olb64 = 0, nosalt = 0;
 141     int enc = 1, printkey = 0, i, k, format = FORMAT_BINARY;
 142     int ret = 1, inl, nopad = 0, non_fips_allow = 0;
 143     unsigned char key[EVP_MAX_KEY_LENGTH], iv[EVP_MAX_IV_LENGTH];
 144     unsigned char *buff = NULL, salt[PKCS5_SALT_LEN];
 145     unsigned long n;
 146 #ifdef ZLIB
 147     int do_zlib = 0;
 148     BIO *bzl = NULL;
 149 #endif
 150
 151     /* first check the program name */
 152     prog = opt_progname(argv[0]);
 153     if (strcmp(prog, "base64") == 0)
 154         format = FORMAT_BASE64;
 155 #ifdef ZLIB
 156     else if (strcmp(prog, "zlib") == 0)
 157         do_zlib = 1;
 158 #endif
 159     else {
 160         cipher = EVP_get_cipherbyname(prog);
 161         if (cipher == NULL && strcmp(prog, "enc") != 0) {
 162             BIO_printf(bio_err, "%s is not a known cipher\n", prog);
 163             goto end;
 164         }
 165     }
 166
 167     prog = opt_init(argc, argv, enc_options);
 168     while ((o = opt_next()) != OPT_EOF) {
 169         switch (o) {
 170         case OPT_EOF:
 171         case OPT_ERR:
 172  opthelp:
 173             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
 174             goto end;
 175         case OPT_HELP:
 176             opt_help(enc_options);
 177             ret = 0;
 178             BIO_printf(bio_err, "Cipher Types\n");
 179             OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_CIPHER_METH,
 180                                    show_ciphers, bio_err);
 181             BIO_printf(bio_err, "\n");
 182             goto end;
 183         case OPT_E:
 184             enc = 1;
 185             break;
 186         case OPT_IN:
 187             infile = opt_arg();
 188             break;
 189         case OPT_OUT:
 190             outfile = opt_arg();
 191             break;
 192         case OPT_PASS:
 193             passarg = opt_arg();
 194             break;
 195         case OPT_ENGINE:
 196             (void)setup_engine(opt_arg(), 0);
 197             break;
 198         case OPT_D:
 199             enc = 0;
 200             break;
 201         case OPT_P:
 202             printkey = 1;
 203             break;
 204         case OPT_V:
 205             verbose = 1;
 206             break;
 207         case OPT_NOPAD:
 208             nopad = 1;
 209             break;
 210         case OPT_SALT:
 211             nosalt = 0;
 212             break;
 213         case OPT_NOSALT:
 214             nosalt = 1;
 215             break;
 216         case OPT_DEBUG:
 217             debug = 1;
 218             break;
 219         case OPT_UPPER_P:
 220             printkey = 2;
 221             break;
 222         case OPT_UPPER_A:
 223             olb64 = 1;
 224             break;
 225         case OPT_A:
 226             format = FORMAT_BASE64;
 227             break;
 228         case OPT_Z:
 229 #ifdef ZLIB
 230             do_zlib = 1;
 231 #endif
 232             break;
 233         case OPT_BUFSIZE:
 234             p = opt_arg();
 235             i = (int)strlen(p) - 1;
 236             k = i >= 1 && p[i] == 'k';
 237             if (k)
 238                 p[i] = '\0';
 239             if (!opt_ulong(opt_arg(), &n))
 240                 goto opthelp;
 241             if (k)
 242                 n *= 1024;
 243             bsize = (int)n;
 244             break;
 245         case OPT_K:
 246             str = opt_arg();
 247             break;
 248         case OPT_KFILE:
 249             in = bio_open_default(opt_arg(), 'r', FORMAT_TEXT);
 250             if (in == NULL)
 251                 goto opthelp;
 252             i = BIO_gets(in, buf, sizeof buf);
 253             BIO_free(in);
 254             in = NULL;
 255             if (i <= 0) {
 256                 BIO_printf(bio_err,
 257                            "%s Can't read key from %s\n", prog, opt_arg());
 258                 goto opthelp;
 259             }
 260             while (--i > 0 && (buf[i] == '\r' || buf[i] == '\n'))
 261                 buf[i] = '\0';
 262             if (i <= 0) {
 263                 BIO_printf(bio_err, "%s: zero length password\n", prog);
 264                 goto opthelp;
 265             }
 266             str = buf;
 267             break;
 268         case OPT_UPPER_K:
 269             hkey = opt_arg();
 270             break;
 271         case OPT_UPPER_S:
 272             hsalt = opt_arg();
 273             break;
 274         case OPT_IV:
 275             hiv = opt_arg();
 276             break;
 277         case OPT_MD:
 278             if (!opt_md(opt_arg(), &dgst))
 279                 goto opthelp;
 280             break;
 281         case OPT_NON_FIPS_ALLOW:
 282             non_fips_allow = 1;
 283             break;
 284         case OPT_CIPHER:
 285             if (!opt_cipher(opt_unknown(), &c))
 286                 goto opthelp;
 287             cipher = c;
 288             break;
 289         case OPT_NONE:
 290             cipher = NULL;
 291             break;
 292         }
 293     }
 294     argc = opt_num_rest();
 295     argv = opt_rest();
 296
 297     if (!app_load_modules(NULL))
 298         goto end;
 299
 300     if (cipher && EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) {
 301         BIO_printf(bio_err, "%s: AEAD ciphers not supported\n", prog);
 302         goto end;
 303     }
 304
 305     if (cipher && (EVP_CIPHER_mode(cipher) == EVP_CIPH_XTS_MODE)) {
 306         BIO_printf(bio_err, "%s XTS ciphers not supported\n", prog);
 307         goto end;
 308     }
 309
 310     if (dgst == NULL)
 311         dgst = EVP_md5();
 312
 313     /* It must be large enough for a base64 encoded line */
 314     if (format == FORMAT_BASE64 && bsize < 80)
 315         bsize = 80;
 316     if (verbose)
 317         BIO_printf(bio_err, "bufsize=%d\n", bsize);
 318
 319     strbuf = app_malloc(SIZE, "strbuf");
 320     buff = app_malloc(EVP_ENCODE_LENGTH(bsize), "evp buffer");
 321
 322     if (debug) {
 323         BIO_set_callback(in, BIO_debug_callback);
 324         BIO_set_callback(out, BIO_debug_callback);
 325         BIO_set_callback_arg(in, (char *)bio_err);
 326         BIO_set_callback_arg(out, (char *)bio_err);
 327     }
 328
 329     if (infile == NULL) {
 330         unbuffer(stdin);
 331         in = dup_bio_in();
 332     } else
 333         in = bio_open_default(infile, 'r', format);
 334     if (in == NULL)
 335         goto end;
 336
 337     if (!str && passarg) {
 338         if (!app_passwd(passarg, NULL, &pass, NULL)) {
 339             BIO_printf(bio_err, "Error getting password\n");
 340             goto end;
 341         }
 342         str = pass;
 343     }
 344
 345     if ((str == NULL) && (cipher != NULL) && (hkey == NULL)) {
 346         for (;;) {
 347             char prompt[200];
 348
 349             BIO_snprintf(prompt, sizeof prompt, "enter %s %s password:",
 350                          OBJ_nid2ln(EVP_CIPHER_nid(cipher)),
 351                          (enc) ? "encryption" : "decryption");
 352             strbuf[0] = '\0';
 353             i = EVP_read_pw_string((char *)strbuf, SIZE, prompt, enc);
 354             if (i == 0) {
 355                 if (strbuf[0] == '\0') {
 356                     ret = 1;
 357                     goto end;
 358                 }
 359                 str = strbuf;
 360                 break;
 361             }
 362             if (i < 0) {
 363                 BIO_printf(bio_err, "bad password read\n");
 364                 goto end;
 365             }
 366         }
 367     }
 368
 369     out = bio_open_default(outfile, 'w', format);
 370     if (out == NULL)
 371         goto end;
 372
 373     rbio = in;
 374     wbio = out;
 375
 376 #ifdef ZLIB
 377     if (do_zlib) {
 378         if ((bzl = BIO_new(BIO_f_zlib())) == NULL)
 379             goto end;
 380         if (enc)
 381             wbio = BIO_push(bzl, wbio);
 382         else
 383             rbio = BIO_push(bzl, rbio);
 384     }
 385 #endif
 386
 387     if (format == FORMAT_BASE64) {
 388         if ((b64 = BIO_new(BIO_f_base64())) == NULL)
 389             goto end;
 390         if (debug) {
 391             BIO_set_callback(b64, BIO_debug_callback);
 392             BIO_set_callback_arg(b64, (char *)bio_err);
 393         }
 394         if (olb64)
 395             BIO_set_flags(b64, BIO_FLAGS_BASE64_NO_NL);
 396         if (enc)
 397             wbio = BIO_push(b64, wbio);
 398         else
 399             rbio = BIO_push(b64, rbio);
 400     }
 401
 402     if (cipher != NULL) {
 403         /*
 404          * Note that str is NULL if a key was passed on the command line, so
 405          * we get no salt in that case. Is this a bug?
 406          */
 407         if (str != NULL) {
 408             /*
 409              * Salt handling: if encrypting generate a salt and write to
 410              * output BIO. If decrypting read salt from input BIO.
 411              */
 412             unsigned char *sptr;
 413             if (nosalt)
 414                 sptr = NULL;
 415             else {
 416                 if (enc) {
 417                     if (hsalt) {
 418                         if (!set_hex(hsalt, salt, sizeof salt)) {
 419                             BIO_printf(bio_err, "invalid hex salt value\n");
 420                             goto end;
 421                         }
 422                     } else if (RAND_bytes(salt, sizeof salt) <= 0)
 423                         goto end;
 424                     /*
 425                      * If -P option then don't bother writing
 426                      */
 427                     if ((printkey != 2)
 428                         && (BIO_write(wbio, magic,
 429                                       sizeof magic - 1) != sizeof magic - 1
 430                             || BIO_write(wbio,
 431                                          (char *)salt,
 432                                          sizeof salt) != sizeof salt)) {
 433                         BIO_printf(bio_err, "error writing output file\n");
 434                         goto end;
 435                     }
 436                 } else if (BIO_read(rbio, mbuf, sizeof mbuf) != sizeof mbuf
 437                            || BIO_read(rbio,
 438                                        (unsigned char *)salt,
 439                                        sizeof salt) != sizeof salt) {
 440                     BIO_printf(bio_err, "error reading input file\n");
 441                     goto end;
 442                 } else if (memcmp(mbuf, magic, sizeof magic - 1)) {
 443                     BIO_printf(bio_err, "bad magic number\n");
 444                     goto end;
 445                 }
 446
 447                 sptr = salt;
 448             }
 449
 450             if (!EVP_BytesToKey(cipher, dgst, sptr,
 451                                 (unsigned char *)str,
 452                                 strlen(str), 1, key, iv)) {
 453                 BIO_printf(bio_err, "EVP_BytesToKey failed\n");
 454                 goto end;
 455             }
 456             /*
 457              * zero the complete buffer or the string passed from the command
 458              * line bug picked up by Larry J. Hughes Jr. <hughes@indiana.edu>
 459              */
 460             if (str == strbuf)
 461                 OPENSSL_cleanse(str, SIZE);
 462             else
 463                 OPENSSL_cleanse(str, strlen(str));
 464         }
 465         if (hiv != NULL) {
 466             int siz = EVP_CIPHER_iv_length(cipher);
 467             if (siz == 0) {
 468                 BIO_printf(bio_err, "warning: iv not use by this cipher\n");
 469             } else if (!set_hex(hiv, iv, sizeof iv)) {
 470                 BIO_printf(bio_err, "invalid hex iv value\n");
 471                 goto end;
 472             }
 473         }
 474         if ((hiv == NULL) && (str == NULL)
 475             && EVP_CIPHER_iv_length(cipher) != 0) {
 476             /*
 477              * No IV was explicitly set and no IV was generated during
 478              * EVP_BytesToKey. Hence the IV is undefined, making correct
 479              * decryption impossible.
 480              */
 481             BIO_printf(bio_err, "iv undefined\n");
 482             goto end;
 483         }
 484         if ((hkey != NULL) && !set_hex(hkey, key, EVP_CIPHER_key_length(cipher))) {
 485             BIO_printf(bio_err, "invalid hex key value\n");
 486             goto end;
 487         }
 488
 489         if ((benc = BIO_new(BIO_f_cipher())) == NULL)
 490             goto end;
 491
 492         /*
 493          * Since we may be changing parameters work on the encryption context
 494          * rather than calling BIO_set_cipher().
 495          */
 496
 497         BIO_get_cipher_ctx(benc, &ctx);
 498
 499         if (non_fips_allow)
 500             EVP_CIPHER_CTX_set_flags(ctx, EVP_CIPH_FLAG_NON_FIPS_ALLOW);
 501
 502         if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, enc)) {
 503             BIO_printf(bio_err, "Error setting cipher %s\n",
 504                        EVP_CIPHER_name(cipher));
 505             ERR_print_errors(bio_err);
 506             goto end;
 507         }
 508
 509         if (nopad)
 510             EVP_CIPHER_CTX_set_padding(ctx, 0);
 511
 512         if (!EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, enc)) {
 513             BIO_printf(bio_err, "Error setting cipher %s\n",
 514                        EVP_CIPHER_name(cipher));
 515             ERR_print_errors(bio_err);
 516             goto end;
 517         }
 518
 519         if (debug) {
 520             BIO_set_callback(benc, BIO_debug_callback);
 521             BIO_set_callback_arg(benc, (char *)bio_err);
 522         }
 523
 524         if (printkey) {
 525             if (!nosalt) {
 526                 printf("salt=");
 527                 for (i = 0; i < (int)sizeof(salt); i++)
 528                     printf("%02X", salt[i]);
 529                 printf("\n");
 530             }
 531             if (cipher->key_len > 0) {
 532                 printf("key=");
 533                 for (i = 0; i < cipher->key_len; i++)
 534                     printf("%02X", key[i]);
 535                 printf("\n");
 536             }
 537             if (cipher->iv_len > 0) {
 538                 printf("iv =");
 539                 for (i = 0; i < cipher->iv_len; i++)
 540                     printf("%02X", iv[i]);
 541                 printf("\n");
 542             }
 543             if (printkey == 2) {
 544                 ret = 0;
 545                 goto end;
 546             }
 547         }
 548     }
 549
 550     /* Only encrypt/decrypt as we write the file */
 551     if (benc != NULL)
 552         wbio = BIO_push(benc, wbio);
 553
 554     for (;;) {
 555         inl = BIO_read(rbio, (char *)buff, bsize);
 556         if (inl <= 0)
 557             break;
 558         if (BIO_write(wbio, (char *)buff, inl) != inl) {
 559             BIO_printf(bio_err, "error writing output file\n");
 560             goto end;
 561         }
 562     }
 563     if (!BIO_flush(wbio)) {
 564         BIO_printf(bio_err, "bad decrypt\n");
 565         goto end;
 566     }
 567
 568     ret = 0;
 569     if (verbose) {
 570         BIO_printf(bio_err, "bytes read   :%8"PRIu64"\n", BIO_number_read(in));
 571         BIO_printf(bio_err, "bytes written:%8"PRIu64"\n", BIO_number_written(out));
 572     }
 573  end:
 574     ERR_print_errors(bio_err);
 575     OPENSSL_free(strbuf);
 576     OPENSSL_free(buff);
 577     BIO_free(in);
 578     BIO_free_all(out);
 579     BIO_free(benc);
 580     BIO_free(b64);
 581 #ifdef ZLIB
 582     BIO_free(bzl);
 583 #endif
 584     OPENSSL_free(pass);
 585     return (ret);
 586 }
 587
 588 static void show_ciphers(const OBJ_NAME *name, void *bio_)
 589 {
 590     BIO *bio = bio_;
 591     static int n;
 592
 593     if (!islower((unsigned char)*name->name))
 594         return;
 595
 596     BIO_printf(bio, "-%-25s", name->name);
 597     if (++n == 3) {
 598         BIO_printf(bio, "\n");
 599         n = 0;
 600     } else
 601         BIO_printf(bio, " ");
 602 }
 603
 604 static int set_hex(char *in, unsigned char *out, int size)
 605 {
 606     int i, n;
 607     unsigned char j;
 608
 609     n = strlen(in);
 610     if (n > (size * 2)) {
 611         BIO_printf(bio_err, "hex string is too long\n");
 612         return (0);
 613     }
 614     memset(out, 0, size);
 615     for (i = 0; i < n; i++) {
 616         j = (unsigned char)*in;
 617         *(in++) = '\0';
 618         if (j == 0)
 619             break;
 620         if (!isxdigit(j)) {
 621             BIO_printf(bio_err, "non-hex digit\n");
 622             return (0);
 623         }
 624         j = (unsigned char)app_hex(j);
 625         if (i & 1)
 626             out[i / 2] |= j;
 627         else
 628             out[i / 2] = (j << 4);
 629     }
 630     return (1);
 631 }