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;
 142     int base64 = 0, informat = FORMAT_BINARY, outformat = FORMAT_BINARY;
 143     int ret = 1, inl, nopad = 0, non_fips_allow = 0;
 144     unsigned char key[EVP_MAX_KEY_LENGTH], iv[EVP_MAX_IV_LENGTH];
 145     unsigned char *buff = NULL, salt[PKCS5_SALT_LEN];
 146     unsigned long n;
 147 #ifdef ZLIB
 148     int do_zlib = 0;
 149     BIO *bzl = NULL;
 150 #endif
 151
 152     /* first check the program name */
 153     prog = opt_progname(argv[0]);
 154     if (strcmp(prog, "base64") == 0)
 155         base64 = 1;
 156 #ifdef ZLIB
 157     else if (strcmp(prog, "zlib") == 0)
 158         do_zlib = 1;
 159 #endif
 160     else {
 161         cipher = EVP_get_cipherbyname(prog);
 162         if (cipher == NULL && strcmp(prog, "enc") != 0) {
 163             BIO_printf(bio_err, "%s is not a known cipher\n", prog);
 164             goto end;
 165         }
 166     }
 167
 168     prog = opt_init(argc, argv, enc_options);
 169     while ((o = opt_next()) != OPT_EOF) {
 170         switch (o) {
 171         case OPT_EOF:
 172         case OPT_ERR:
 173  opthelp:
 174             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
 175             goto end;
 176         case OPT_HELP:
 177             opt_help(enc_options);
 178             ret = 0;
 179             BIO_printf(bio_err, "Cipher Types\n");
 180             OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_CIPHER_METH,
 181                                    show_ciphers, bio_err);
 182             BIO_printf(bio_err, "\n");
 183             goto end;
 184         case OPT_E:
 185             enc = 1;
 186             break;
 187         case OPT_IN:
 188             infile = opt_arg();
 189             break;
 190         case OPT_OUT:
 191             outfile = opt_arg();
 192             break;
 193         case OPT_PASS:
 194             passarg = opt_arg();
 195             break;
 196         case OPT_ENGINE:
 197             (void)setup_engine(opt_arg(), 0);
 198             break;
 199         case OPT_D:
 200             enc = 0;
 201             break;
 202         case OPT_P:
 203             printkey = 1;
 204             break;
 205         case OPT_V:
 206             verbose = 1;
 207             break;
 208         case OPT_NOPAD:
 209             nopad = 1;
 210             break;
 211         case OPT_SALT:
 212             nosalt = 0;
 213             break;
 214         case OPT_NOSALT:
 215             nosalt = 1;
 216             break;
 217         case OPT_DEBUG:
 218             debug = 1;
 219             break;
 220         case OPT_UPPER_P:
 221             printkey = 2;
 222             break;
 223         case OPT_UPPER_A:
 224             olb64 = 1;
 225             break;
 226         case OPT_A:
 227             base64 = 1;
 228             break;
 229         case OPT_Z:
 230 #ifdef ZLIB
 231             do_zlib = 1;
 232 #endif
 233             break;
 234         case OPT_BUFSIZE:
 235             p = opt_arg();
 236             i = (int)strlen(p) - 1;
 237             k = i >= 1 && p[i] == 'k';
 238             if (k)
 239                 p[i] = '\0';
 240             if (!opt_ulong(opt_arg(), &n))
 241                 goto opthelp;
 242             if (k)
 243                 n *= 1024;
 244             bsize = (int)n;
 245             break;
 246         case OPT_K:
 247             str = opt_arg();
 248             break;
 249         case OPT_KFILE:
 250             in = bio_open_default(opt_arg(), 'r', FORMAT_TEXT);
 251             if (in == NULL)
 252                 goto opthelp;
 253             i = BIO_gets(in, buf, sizeof buf);
 254             BIO_free(in);
 255             in = NULL;
 256             if (i <= 0) {
 257                 BIO_printf(bio_err,
 258                            "%s Can't read key from %s\n", prog, opt_arg());
 259                 goto opthelp;
 260             }
 261             while (--i > 0 && (buf[i] == '\r' || buf[i] == '\n'))
 262                 buf[i] = '\0';
 263             if (i <= 0) {
 264                 BIO_printf(bio_err, "%s: zero length password\n", prog);
 265                 goto opthelp;
 266             }
 267             str = buf;
 268             break;
 269         case OPT_UPPER_K:
 270             hkey = opt_arg();
 271             break;
 272         case OPT_UPPER_S:
 273             hsalt = opt_arg();
 274             break;
 275         case OPT_IV:
 276             hiv = opt_arg();
 277             break;
 278         case OPT_MD:
 279             if (!opt_md(opt_arg(), &dgst))
 280                 goto opthelp;
 281             break;
 282         case OPT_NON_FIPS_ALLOW:
 283             non_fips_allow = 1;
 284             break;
 285         case OPT_CIPHER:
 286             if (!opt_cipher(opt_unknown(), &c))
 287                 goto opthelp;
 288             cipher = c;
 289             break;
 290         case OPT_NONE:
 291             cipher = NULL;
 292             break;
 293         }
 294     }
 295     argc = opt_num_rest();
 296     argv = opt_rest();
 297
 298     if (cipher && EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) {
 299         BIO_printf(bio_err, "%s: AEAD ciphers not supported\n", prog);
 300         goto end;
 301     }
 302
 303     if (cipher && (EVP_CIPHER_mode(cipher) == EVP_CIPH_XTS_MODE)) {
 304         BIO_printf(bio_err, "%s XTS ciphers not supported\n", prog);
 305         goto end;
 306     }
 307
 308     if (dgst == NULL)
 309         dgst = EVP_md5();
 310
 311     /* It must be large enough for a base64 encoded line */
 312     if (base64 && bsize < 80)
 313         bsize = 80;
 314     if (verbose)
 315         BIO_printf(bio_err, "bufsize=%d\n", bsize);
 316
 317     if (base64) {
 318         if (enc)
 319             outformat = FORMAT_BASE64;
 320         else
 321             informat = FORMAT_BASE64;
 322     }
 323
 324     strbuf = app_malloc(SIZE, "strbuf");
 325     buff = app_malloc(EVP_ENCODE_LENGTH(bsize), "evp buffer");
 326
 327     if (debug) {
 328         BIO_set_callback(in, BIO_debug_callback);
 329         BIO_set_callback(out, BIO_debug_callback);
 330         BIO_set_callback_arg(in, (char *)bio_err);
 331         BIO_set_callback_arg(out, (char *)bio_err);
 332     }
 333
 334     if (infile == NULL) {
 335         unbuffer(stdin);
 336         in = dup_bio_in(informat);
 337     } else
 338         in = bio_open_default(infile, 'r', informat);
 339     if (in == NULL)
 340         goto end;
 341
 342     if (!str && passarg) {
 343         if (!app_passwd(passarg, NULL, &pass, NULL)) {
 344             BIO_printf(bio_err, "Error getting password\n");
 345             goto end;
 346         }
 347         str = pass;
 348     }
 349
 350     if ((str == NULL) && (cipher != NULL) && (hkey == NULL)) {
 351         for (;;) {
 352             char prompt[200];
 353
 354             BIO_snprintf(prompt, sizeof prompt, "enter %s %s password:",
 355                          OBJ_nid2ln(EVP_CIPHER_nid(cipher)),
 356                          (enc) ? "encryption" : "decryption");
 357             strbuf[0] = '\0';
 358             i = EVP_read_pw_string((char *)strbuf, SIZE, prompt, enc);
 359             if (i == 0) {
 360                 if (strbuf[0] == '\0') {
 361                     ret = 1;
 362                     goto end;
 363                 }
 364                 str = strbuf;
 365                 break;
 366             }
 367             if (i < 0) {
 368                 BIO_printf(bio_err, "bad password read\n");
 369                 goto end;
 370             }
 371         }
 372     }
 373
 374     out = bio_open_default(outfile, 'w', outformat);
 375     if (out == NULL)
 376         goto end;
 377
 378     rbio = in;
 379     wbio = out;
 380
 381 #ifdef ZLIB
 382     if (do_zlib) {
 383         if ((bzl = BIO_new(BIO_f_zlib())) == NULL)
 384             goto end;
 385         if (enc)
 386             wbio = BIO_push(bzl, wbio);
 387         else
 388             rbio = BIO_push(bzl, rbio);
 389     }
 390 #endif
 391
 392     if (base64) {
 393         if ((b64 = BIO_new(BIO_f_base64())) == NULL)
 394             goto end;
 395         if (debug) {
 396             BIO_set_callback(b64, BIO_debug_callback);
 397             BIO_set_callback_arg(b64, (char *)bio_err);
 398         }
 399         if (olb64)
 400             BIO_set_flags(b64, BIO_FLAGS_BASE64_NO_NL);
 401         if (enc)
 402             wbio = BIO_push(b64, wbio);
 403         else
 404             rbio = BIO_push(b64, rbio);
 405     }
 406
 407     if (cipher != NULL) {
 408         /*
 409          * Note that str is NULL if a key was passed on the command line, so
 410          * we get no salt in that case. Is this a bug?
 411          */
 412         if (str != NULL) {
 413             /*
 414              * Salt handling: if encrypting generate a salt and write to
 415              * output BIO. If decrypting read salt from input BIO.
 416              */
 417             unsigned char *sptr;
 418             if (nosalt)
 419                 sptr = NULL;
 420             else {
 421                 if (enc) {
 422                     if (hsalt) {
 423                         if (!set_hex(hsalt, salt, sizeof salt)) {
 424                             BIO_printf(bio_err, "invalid hex salt value\n");
 425                             goto end;
 426                         }
 427                     } else if (RAND_bytes(salt, sizeof salt) <= 0)
 428                         goto end;
 429                     /*
 430                      * If -P option then don't bother writing
 431                      */
 432                     if ((printkey != 2)
 433                         && (BIO_write(wbio, magic,
 434                                       sizeof magic - 1) != sizeof magic - 1
 435                             || BIO_write(wbio,
 436                                          (char *)salt,
 437                                          sizeof salt) != sizeof salt)) {
 438                         BIO_printf(bio_err, "error writing output file\n");
 439                         goto end;
 440                     }
 441                 } else if (BIO_read(rbio, mbuf, sizeof mbuf) != sizeof mbuf
 442                            || BIO_read(rbio,
 443                                        (unsigned char *)salt,
 444                                        sizeof salt) != sizeof salt) {
 445                     BIO_printf(bio_err, "error reading input file\n");
 446                     goto end;
 447                 } else if (memcmp(mbuf, magic, sizeof magic - 1)) {
 448                     BIO_printf(bio_err, "bad magic number\n");
 449                     goto end;
 450                 }
 451
 452                 sptr = salt;
 453             }
 454
 455             if (!EVP_BytesToKey(cipher, dgst, sptr,
 456                                 (unsigned char *)str,
 457                                 strlen(str), 1, key, iv)) {
 458                 BIO_printf(bio_err, "EVP_BytesToKey failed\n");
 459                 goto end;
 460             }
 461             /*
 462              * zero the complete buffer or the string passed from the command
 463              * line bug picked up by Larry J. Hughes Jr. <hughes@indiana.edu>
 464              */
 465             if (str == strbuf)
 466                 OPENSSL_cleanse(str, SIZE);
 467             else
 468                 OPENSSL_cleanse(str, strlen(str));
 469         }
 470         if (hiv != NULL) {
 471             int siz = EVP_CIPHER_iv_length(cipher);
 472             if (siz == 0) {
 473                 BIO_printf(bio_err, "warning: iv not use by this cipher\n");
 474             } else if (!set_hex(hiv, iv, sizeof iv)) {
 475                 BIO_printf(bio_err, "invalid hex iv value\n");
 476                 goto end;
 477             }
 478         }
 479         if ((hiv == NULL) && (str == NULL)
 480             && EVP_CIPHER_iv_length(cipher) != 0) {
 481             /*
 482              * No IV was explicitly set and no IV was generated during
 483              * EVP_BytesToKey. Hence the IV is undefined, making correct
 484              * decryption impossible.
 485              */
 486             BIO_printf(bio_err, "iv undefined\n");
 487             goto end;
 488         }
 489         if ((hkey != NULL) && !set_hex(hkey, key, EVP_CIPHER_key_length(cipher))) {
 490             BIO_printf(bio_err, "invalid hex key value\n");
 491             goto end;
 492         }
 493
 494         if ((benc = BIO_new(BIO_f_cipher())) == NULL)
 495             goto end;
 496
 497         /*
 498          * Since we may be changing parameters work on the encryption context
 499          * rather than calling BIO_set_cipher().
 500          */
 501
 502         BIO_get_cipher_ctx(benc, &ctx);
 503
 504         if (non_fips_allow)
 505             EVP_CIPHER_CTX_set_flags(ctx, EVP_CIPH_FLAG_NON_FIPS_ALLOW);
 506
 507         if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, enc)) {
 508             BIO_printf(bio_err, "Error setting cipher %s\n",
 509                        EVP_CIPHER_name(cipher));
 510             ERR_print_errors(bio_err);
 511             goto end;
 512         }
 513
 514         if (nopad)
 515             EVP_CIPHER_CTX_set_padding(ctx, 0);
 516
 517         if (!EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, enc)) {
 518             BIO_printf(bio_err, "Error setting cipher %s\n",
 519                        EVP_CIPHER_name(cipher));
 520             ERR_print_errors(bio_err);
 521             goto end;
 522         }
 523
 524         if (debug) {
 525             BIO_set_callback(benc, BIO_debug_callback);
 526             BIO_set_callback_arg(benc, (char *)bio_err);
 527         }
 528
 529         if (printkey) {
 530             if (!nosalt) {
 531                 printf("salt=");
 532                 for (i = 0; i < (int)sizeof(salt); i++)
 533                     printf("%02X", salt[i]);
 534                 printf("\n");
 535             }
 536             if (cipher->key_len > 0) {
 537                 printf("key=");
 538                 for (i = 0; i < cipher->key_len; i++)
 539                     printf("%02X", key[i]);
 540                 printf("\n");
 541             }
 542             if (cipher->iv_len > 0) {
 543                 printf("iv =");
 544                 for (i = 0; i < cipher->iv_len; i++)
 545                     printf("%02X", iv[i]);
 546                 printf("\n");
 547             }
 548             if (printkey == 2) {
 549                 ret = 0;
 550                 goto end;
 551             }
 552         }
 553     }
 554
 555     /* Only encrypt/decrypt as we write the file */
 556     if (benc != NULL)
 557         wbio = BIO_push(benc, wbio);
 558
 559     for (;;) {
 560         inl = BIO_read(rbio, (char *)buff, bsize);
 561         if (inl <= 0)
 562             break;
 563         if (BIO_write(wbio, (char *)buff, inl) != inl) {
 564             BIO_printf(bio_err, "error writing output file\n");
 565             goto end;
 566         }
 567     }
 568     if (!BIO_flush(wbio)) {
 569         BIO_printf(bio_err, "bad decrypt\n");
 570         goto end;
 571     }
 572
 573     ret = 0;
 574     if (verbose) {
 575         BIO_printf(bio_err, "bytes read   :%8"PRIu64"\n", BIO_number_read(in));
 576         BIO_printf(bio_err, "bytes written:%8"PRIu64"\n", BIO_number_written(out));
 577     }
 578  end:
 579     ERR_print_errors(bio_err);
 580     OPENSSL_free(strbuf);
 581     OPENSSL_free(buff);
 582     BIO_free(in);
 583     BIO_free_all(out);
 584     BIO_free(benc);
 585     BIO_free(b64);
 586 #ifdef ZLIB
 587     BIO_free(bzl);
 588 #endif
 589     OPENSSL_free(pass);
 590     return (ret);
 591 }
 592
 593 static void show_ciphers(const OBJ_NAME *name, void *bio_)
 594 {
 595     BIO *bio = bio_;
 596     static int n;
 597
 598     if (!islower((unsigned char)*name->name))
 599         return;
 600
 601     BIO_printf(bio, "-%-25s", name->name);
 602     if (++n == 3) {
 603         BIO_printf(bio, "\n");
 604         n = 0;
 605     } else
 606         BIO_printf(bio, " ");
 607 }
 608
 609 static int set_hex(char *in, unsigned char *out, int size)
 610 {
 611     int i, n;
 612     unsigned char j;
 613
 614     n = strlen(in);
 615     if (n > (size * 2)) {
 616         BIO_printf(bio_err, "hex string is too long\n");
 617         return (0);
 618     }
 619     memset(out, 0, size);
 620     for (i = 0; i < n; i++) {
 621         j = (unsigned char)*in;
 622         *(in++) = '\0';
 623         if (j == 0)
 624             break;
 625         if (!isxdigit(j)) {
 626             BIO_printf(bio_err, "non-hex digit\n");
 627             return (0);
 628         }
 629         j = (unsigned char)app_hex(j);
 630         if (i & 1)
 631             out[i / 2] |= j;
 632         else
 633             out[i / 2] = (j << 4);
 634     }
 635     return (1);
 636 }