apps/dgst.c

   1 /*
   2  * Copyright 1995-2021 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 #include <stdio.h>
  11 #include <string.h>
  12 #include <stdlib.h>
  13 #include "apps.h"
  14 #include "progs.h"
  15 #include <openssl/bio.h>
  16 #include <openssl/err.h>
  17 #include <openssl/evp.h>
  18 #include <openssl/objects.h>
  19 #include <openssl/x509.h>
  20 #include <openssl/pem.h>
  21 #include <openssl/hmac.h>
  22 #include <ctype.h>
  23
  24 #undef BUFSIZE
  25 #define BUFSIZE 1024*8
  26
  27 int do_fp(BIO *out, unsigned char *buf, BIO *bp, int sep, int binout, int xoflen,
  28           EVP_PKEY *key, unsigned char *sigin, int siglen,
  29           const char *sig_name, const char *md_name,
  30           const char *file);
  31 static void show_digests(const OBJ_NAME *name, void *bio_);
  32
  33 struct doall_dgst_digests {
  34     BIO *bio;
  35     int n;
  36 };
  37
  38 typedef enum OPTION_choice {
  39     OPT_COMMON,
  40     OPT_LIST,
  41     OPT_C, OPT_R, OPT_OUT, OPT_SIGN, OPT_PASSIN, OPT_VERIFY,
  42     OPT_PRVERIFY, OPT_SIGNATURE, OPT_KEYFORM, OPT_ENGINE, OPT_ENGINE_IMPL,
  43     OPT_HEX, OPT_BINARY, OPT_DEBUG, OPT_FIPS_FINGERPRINT,
  44     OPT_HMAC, OPT_MAC, OPT_SIGOPT, OPT_MACOPT, OPT_XOFLEN,
  45     OPT_DIGEST,
  46     OPT_R_ENUM, OPT_PROV_ENUM
  47 } OPTION_CHOICE;
  48
  49 const OPTIONS dgst_options[] = {
  50     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [file...]\n"},
  51
  52     OPT_SECTION("General"),
  53     {"help", OPT_HELP, '-', "Display this summary"},
  54     {"list", OPT_LIST, '-', "List digests"},
  55 #ifndef OPENSSL_NO_ENGINE
  56     {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
  57     {"engine_impl", OPT_ENGINE_IMPL, '-',
  58      "Also use engine given by -engine for digest operations"},
  59 #endif
  60     {"passin", OPT_PASSIN, 's', "Input file pass phrase source"},
  61
  62     OPT_SECTION("Output"),
  63     {"c", OPT_C, '-', "Print the digest with separating colons"},
  64     {"r", OPT_R, '-', "Print the digest in coreutils format"},
  65     {"out", OPT_OUT, '>', "Output to filename rather than stdout"},
  66     {"keyform", OPT_KEYFORM, 'f', "Key file format (ENGINE, other values ignored)"},
  67     {"hex", OPT_HEX, '-', "Print as hex dump"},
  68     {"binary", OPT_BINARY, '-', "Print in binary form"},
  69     {"xoflen", OPT_XOFLEN, 'p', "Output length for XOF algorithms"},
  70     {"d", OPT_DEBUG, '-', "Print debug info"},
  71     {"debug", OPT_DEBUG, '-', "Print debug info"},
  72
  73     OPT_SECTION("Signing"),
  74     {"sign", OPT_SIGN, 's', "Sign digest using private key"},
  75     {"verify", OPT_VERIFY, 's', "Verify a signature using public key"},
  76     {"prverify", OPT_PRVERIFY, 's', "Verify a signature using private key"},
  77     {"sigopt", OPT_SIGOPT, 's', "Signature parameter in n:v form"},
  78     {"signature", OPT_SIGNATURE, '<', "File with signature to verify"},
  79     {"hmac", OPT_HMAC, 's', "Create hashed MAC with key"},
  80     {"mac", OPT_MAC, 's', "Create MAC (not necessarily HMAC)"},
  81     {"macopt", OPT_MACOPT, 's', "MAC algorithm parameters in n:v form or key"},
  82     {"", OPT_DIGEST, '-', "Any supported digest"},
  83     {"fips-fingerprint", OPT_FIPS_FINGERPRINT, '-',
  84      "Compute HMAC with the key used in OpenSSL-FIPS fingerprint"},
  85
  86     OPT_R_OPTIONS,
  87     OPT_PROV_OPTIONS,
  88
  89     OPT_PARAMETERS(),
  90     {"file", 0, 0, "Files to digest (optional; default is stdin)"},
  91     {NULL}
  92 };
  93
  94 int dgst_main(int argc, char **argv)
  95 {
  96     BIO *in = NULL, *inp, *bmd = NULL, *out = NULL;
  97     ENGINE *e = NULL, *impl = NULL;
  98     EVP_PKEY *sigkey = NULL;
  99     STACK_OF(OPENSSL_STRING) *sigopts = NULL, *macopts = NULL;
 100     char *hmac_key = NULL;
 101     char *mac_name = NULL, *digestname = NULL;
 102     char *passinarg = NULL, *passin = NULL;
 103     EVP_MD *md = NULL;
 104     const char *outfile = NULL, *keyfile = NULL, *prog = NULL;
 105     const char *sigfile = NULL;
 106     const char *md_name = NULL;
 107     OPTION_CHOICE o;
 108     int separator = 0, debug = 0, keyform = FORMAT_UNDEF, siglen = 0;
 109     int i, ret = 1, out_bin = -1, want_pub = 0, do_verify = 0;
 110     int xoflen = 0;
 111     unsigned char *buf = NULL, *sigbuf = NULL;
 112     int engine_impl = 0;
 113     struct doall_dgst_digests dec;
 114
 115     buf = app_malloc(BUFSIZE, "I/O buffer");
 116     md = (EVP_MD *)EVP_get_digestbyname(argv[0]);
 117
 118     prog = opt_init(argc, argv, dgst_options);
 119     while ((o = opt_next()) != OPT_EOF) {
 120         switch (o) {
 121         case OPT_EOF:
 122         case OPT_ERR:
 123  opthelp:
 124             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
 125             goto end;
 126         case OPT_HELP:
 127             opt_help(dgst_options);
 128             ret = 0;
 129             goto end;
 130         case OPT_LIST:
 131             BIO_printf(bio_out, "Supported digests:\n");
 132             dec.bio = bio_out;
 133             dec.n = 0;
 134             OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_MD_METH,
 135                                    show_digests, &dec);
 136             BIO_printf(bio_out, "\n");
 137             ret = 0;
 138             goto end;
 139         case OPT_C:
 140             separator = 1;
 141             break;
 142         case OPT_R:
 143             separator = 2;
 144             break;
 145         case OPT_R_CASES:
 146             if (!opt_rand(o))
 147                 goto end;
 148             break;
 149         case OPT_OUT:
 150             outfile = opt_arg();
 151             break;
 152         case OPT_SIGN:
 153             keyfile = opt_arg();
 154             break;
 155         case OPT_PASSIN:
 156             passinarg = opt_arg();
 157             break;
 158         case OPT_VERIFY:
 159             keyfile = opt_arg();
 160             want_pub = do_verify = 1;
 161             break;
 162         case OPT_PRVERIFY:
 163             keyfile = opt_arg();
 164             do_verify = 1;
 165             break;
 166         case OPT_SIGNATURE:
 167             sigfile = opt_arg();
 168             break;
 169         case OPT_KEYFORM:
 170             if (!opt_format(opt_arg(), OPT_FMT_ANY, &keyform))
 171                 goto opthelp;
 172             break;
 173         case OPT_ENGINE:
 174             e = setup_engine(opt_arg(), 0);
 175             break;
 176         case OPT_ENGINE_IMPL:
 177             engine_impl = 1;
 178             break;
 179         case OPT_HEX:
 180             out_bin = 0;
 181             break;
 182         case OPT_BINARY:
 183             out_bin = 1;
 184             break;
 185         case OPT_XOFLEN:
 186             xoflen = atoi(opt_arg());
 187             break;
 188         case OPT_DEBUG:
 189             debug = 1;
 190             break;
 191         case OPT_FIPS_FINGERPRINT:
 192             hmac_key = "etaonrishdlcupfm";
 193             break;
 194         case OPT_HMAC:
 195             hmac_key = opt_arg();
 196             break;
 197         case OPT_MAC:
 198             mac_name = opt_arg();
 199             break;
 200         case OPT_SIGOPT:
 201             if (!sigopts)
 202                 sigopts = sk_OPENSSL_STRING_new_null();
 203             if (!sigopts || !sk_OPENSSL_STRING_push(sigopts, opt_arg()))
 204                 goto opthelp;
 205             break;
 206         case OPT_MACOPT:
 207             if (!macopts)
 208                 macopts = sk_OPENSSL_STRING_new_null();
 209             if (!macopts || !sk_OPENSSL_STRING_push(macopts, opt_arg()))
 210                 goto opthelp;
 211             break;
 212         case OPT_DIGEST:
 213             digestname = opt_unknown();
 214             break;
 215         case OPT_PROV_CASES:
 216             if (!opt_provider(o))
 217                 goto end;
 218             break;
 219         }
 220     }
 221
 222     /* Remaining args are files to digest. */
 223     argc = opt_num_rest();
 224     argv = opt_rest();
 225     if (keyfile != NULL && argc > 1) {
 226         BIO_printf(bio_err, "%s: Can only sign or verify one file.\n", prog);
 227         goto end;
 228     }
 229     if (!app_RAND_load())
 230         goto end;
 231
 232     if (digestname != NULL) {
 233         if (!opt_md(digestname, &md))
 234             goto opthelp;
 235     }
 236
 237     if (do_verify && sigfile == NULL) {
 238         BIO_printf(bio_err,
 239                    "No signature to verify: use the -signature option\n");
 240         goto end;
 241     }
 242     if (engine_impl)
 243         impl = e;
 244
 245     in = BIO_new(BIO_s_file());
 246     bmd = BIO_new(BIO_f_md());
 247     if ((in == NULL) || (bmd == NULL)) {
 248         ERR_print_errors(bio_err);
 249         goto end;
 250     }
 251
 252     if (debug) {
 253         BIO_set_callback(in, BIO_debug_callback);
 254         /* needed for windows 3.1 */
 255         BIO_set_callback_arg(in, (char *)bio_err);
 256     }
 257
 258     if (!app_passwd(passinarg, NULL, &passin, NULL)) {
 259         BIO_printf(bio_err, "Error getting password\n");
 260         goto end;
 261     }
 262
 263     if (out_bin == -1) {
 264         if (keyfile != NULL)
 265             out_bin = 1;
 266         else
 267             out_bin = 0;
 268     }
 269
 270     out = bio_open_default(outfile, 'w', out_bin ? FORMAT_BINARY : FORMAT_TEXT);
 271     if (out == NULL)
 272         goto end;
 273
 274     if ((!(mac_name == NULL) + !(keyfile == NULL) + !(hmac_key == NULL)) > 1) {
 275         BIO_printf(bio_err, "MAC and Signing key cannot both be specified\n");
 276         goto end;
 277     }
 278
 279     if (keyfile != NULL) {
 280         int type;
 281
 282         if (want_pub)
 283             sigkey = load_pubkey(keyfile, keyform, 0, NULL, e, "public key");
 284         else
 285             sigkey = load_key(keyfile, keyform, 0, passin, e, "private key");
 286         if (sigkey == NULL) {
 287             /*
 288              * load_[pub]key() has already printed an appropriate message
 289              */
 290             goto end;
 291         }
 292         type = EVP_PKEY_id(sigkey);
 293         if (type == EVP_PKEY_ED25519 || type == EVP_PKEY_ED448) {
 294             /*
 295              * We implement PureEdDSA for these which doesn't have a separate
 296              * digest, and only supports one shot.
 297              */
 298             BIO_printf(bio_err, "Key type not supported for this operation\n");
 299             goto end;
 300         }
 301     }
 302
 303     if (mac_name != NULL) {
 304         EVP_PKEY_CTX *mac_ctx = NULL;
 305         int r = 0;
 306         if (!init_gen_str(&mac_ctx, mac_name, impl, 0, NULL, NULL))
 307             goto mac_end;
 308         if (macopts != NULL) {
 309             char *macopt;
 310             for (i = 0; i < sk_OPENSSL_STRING_num(macopts); i++) {
 311                 macopt = sk_OPENSSL_STRING_value(macopts, i);
 312                 if (pkey_ctrl_string(mac_ctx, macopt) <= 0) {
 313                     BIO_printf(bio_err,
 314                                "MAC parameter error \"%s\"\n", macopt);
 315                     ERR_print_errors(bio_err);
 316                     goto mac_end;
 317                 }
 318             }
 319         }
 320         if (EVP_PKEY_keygen(mac_ctx, &sigkey) <= 0) {
 321             BIO_puts(bio_err, "Error generating key\n");
 322             ERR_print_errors(bio_err);
 323             goto mac_end;
 324         }
 325         r = 1;
 326  mac_end:
 327         EVP_PKEY_CTX_free(mac_ctx);
 328         if (r == 0)
 329             goto end;
 330     }
 331
 332     if (hmac_key != NULL) {
 333         if (md == NULL)
 334             md = (EVP_MD *)EVP_sha256();
 335         sigkey = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, impl,
 336                                               (unsigned char *)hmac_key,
 337                                               strlen(hmac_key));
 338         if (sigkey == NULL)
 339             goto end;
 340     }
 341
 342     if (sigkey != NULL) {
 343         EVP_MD_CTX *mctx = NULL;
 344         EVP_PKEY_CTX *pctx = NULL;
 345         int r;
 346         if (!BIO_get_md_ctx(bmd, &mctx)) {
 347             BIO_printf(bio_err, "Error getting context\n");
 348             ERR_print_errors(bio_err);
 349             goto end;
 350         }
 351         if (do_verify)
 352             r = EVP_DigestVerifyInit(mctx, &pctx, md, impl, sigkey);
 353         else
 354             r = EVP_DigestSignInit(mctx, &pctx, md, impl, sigkey);
 355         if (!r) {
 356             BIO_printf(bio_err, "Error setting context\n");
 357             ERR_print_errors(bio_err);
 358             goto end;
 359         }
 360         if (sigopts != NULL) {
 361             char *sigopt;
 362             for (i = 0; i < sk_OPENSSL_STRING_num(sigopts); i++) {
 363                 sigopt = sk_OPENSSL_STRING_value(sigopts, i);
 364                 if (pkey_ctrl_string(pctx, sigopt) <= 0) {
 365                     BIO_printf(bio_err, "parameter error \"%s\"\n", sigopt);
 366                     ERR_print_errors(bio_err);
 367                     goto end;
 368                 }
 369             }
 370         }
 371     }
 372     /* we use md as a filter, reading from 'in' */
 373     else {
 374         EVP_MD_CTX *mctx = NULL;
 375         if (!BIO_get_md_ctx(bmd, &mctx)) {
 376             BIO_printf(bio_err, "Error getting context\n");
 377             ERR_print_errors(bio_err);
 378             goto end;
 379         }
 380         if (md == NULL)
 381             md = (EVP_MD *)EVP_sha256();
 382         if (!EVP_DigestInit_ex(mctx, md, impl)) {
 383             BIO_printf(bio_err, "Error setting digest\n");
 384             ERR_print_errors(bio_err);
 385             goto end;
 386         }
 387     }
 388
 389     if (sigfile != NULL && sigkey != NULL) {
 390         BIO *sigbio = BIO_new_file(sigfile, "rb");
 391         if (sigbio == NULL) {
 392             BIO_printf(bio_err, "Error opening signature file %s\n", sigfile);
 393             ERR_print_errors(bio_err);
 394             goto end;
 395         }
 396         siglen = EVP_PKEY_size(sigkey);
 397         sigbuf = app_malloc(siglen, "signature buffer");
 398         siglen = BIO_read(sigbio, sigbuf, siglen);
 399         BIO_free(sigbio);
 400         if (siglen <= 0) {
 401             BIO_printf(bio_err, "Error reading signature file %s\n", sigfile);
 402             ERR_print_errors(bio_err);
 403             goto end;
 404         }
 405     }
 406     inp = BIO_push(bmd, in);
 407
 408     if (md == NULL) {
 409         EVP_MD_CTX *tctx;
 410
 411         BIO_get_md_ctx(bmd, &tctx);
 412         md = EVP_MD_CTX_get1_md(tctx);
 413     }
 414     if (md != NULL)
 415         md_name = EVP_MD_name(md);
 416
 417     if (xoflen > 0) {
 418         if (!(EVP_MD_flags(md) & EVP_MD_FLAG_XOF)) {
 419             BIO_printf(bio_err, "Length can only be specified for XOF\n");
 420             goto end;
 421         }
 422         if (sigkey != NULL) {
 423             BIO_printf(bio_err, "Signing key cannot be specified for XOF\n");
 424             goto end;
 425         }
 426     }
 427
 428     if (argc == 0) {
 429         BIO_set_fp(in, stdin, BIO_NOCLOSE);
 430         ret = do_fp(out, buf, inp, separator, out_bin, xoflen, sigkey, sigbuf,
 431                     siglen, NULL, md_name, "stdin");
 432     } else {
 433         const char *sig_name = NULL;
 434         if (!out_bin) {
 435             if (sigkey != NULL)
 436                 sig_name = EVP_PKEY_get0_type_name(sigkey);
 437         }
 438         ret = 0;
 439         for (i = 0; i < argc; i++) {
 440             int r;
 441             if (BIO_read_filename(in, argv[i]) <= 0) {
 442                 perror(argv[i]);
 443                 ret++;
 444                 continue;
 445             } else {
 446                 r = do_fp(out, buf, inp, separator, out_bin, xoflen,
 447                           sigkey, sigbuf, siglen, sig_name, md_name, argv[i]);
 448             }
 449             if (r)
 450                 ret = r;
 451             (void)BIO_reset(bmd);
 452         }
 453     }
 454  end:
 455     OPENSSL_clear_free(buf, BUFSIZE);
 456     BIO_free(in);
 457     OPENSSL_free(passin);
 458     BIO_free_all(out);
 459     EVP_MD_free(md);
 460     EVP_PKEY_free(sigkey);
 461     sk_OPENSSL_STRING_free(sigopts);
 462     sk_OPENSSL_STRING_free(macopts);
 463     OPENSSL_free(sigbuf);
 464     BIO_free(bmd);
 465     release_engine(e);
 466     return ret;
 467 }
 468
 469 static void show_digests(const OBJ_NAME *name, void *arg)
 470 {
 471     struct doall_dgst_digests *dec = (struct doall_dgst_digests *)arg;
 472     const EVP_MD *md = NULL;
 473
 474     /* Filter out signed digests (a.k.a signature algorithms) */
 475     if (strstr(name->name, "rsa") != NULL || strstr(name->name, "RSA") != NULL)
 476         return;
 477
 478     if (!islower((unsigned char)*name->name))
 479         return;
 480
 481     /* Filter out message digests that we cannot use */
 482     md = EVP_get_digestbyname(name->name);
 483     if (md == NULL)
 484         return;
 485
 486     BIO_printf(dec->bio, "-%-25s", name->name);
 487     if (++dec->n == 3) {
 488         BIO_printf(dec->bio, "\n");
 489         dec->n = 0;
 490     } else {
 491         BIO_printf(dec->bio, " ");
 492     }
 493 }
 494
 495 /*
 496  * The newline_escape_filename function performs newline escaping for any
 497  * filename that contains a newline.  This function also takes a pointer
 498  * to backslash. The backslash pointer is a flag to indicating whether a newline
 499  * is present in the filename.  If a newline is present, the backslash flag is
 500  * set and the output format will contain a backslash at the beginning of the
 501  * digest output. This output format is to replicate the output format found
 502  * in the '*sum' checksum programs. This aims to preserve backward
 503  * compatibility.
 504  */
 505 static const char *newline_escape_filename(const char *file, int * backslash)
 506 {
 507     size_t i, e = 0, length = strlen(file), newline_count = 0, mem_len = 0;
 508     char *file_cpy = NULL;
 509
 510     for (i = 0; i < length; i++)
 511         if (file[i] == '\n')
 512             newline_count++;
 513
 514     mem_len = length + newline_count + 1;
 515     file_cpy = app_malloc(mem_len, file);
 516     i = 0;
 517
 518     while(e < length) {
 519         const char c = file[e];
 520         if (c == '\n') {
 521             file_cpy[i++] = '\\';
 522             file_cpy[i++] = 'n';
 523             *backslash = 1;
 524         } else {
 525             file_cpy[i++] = c;
 526         }
 527         e++;
 528     }
 529     file_cpy[i] = '\0';
 530     return (const char*)file_cpy;
 531 }
 532
 533
 534 int do_fp(BIO *out, unsigned char *buf, BIO *bp, int sep, int binout, int xoflen,
 535           EVP_PKEY *key, unsigned char *sigin, int siglen,
 536           const char *sig_name, const char *md_name,
 537           const char *file)
 538 {
 539     size_t len = BUFSIZE;
 540     int i, backslash = 0, ret = 1;
 541     unsigned char *allocated_buf = NULL;
 542
 543     while (BIO_pending(bp) || !BIO_eof(bp)) {
 544         i = BIO_read(bp, (char *)buf, BUFSIZE);
 545         if (i < 0) {
 546             BIO_printf(bio_err, "Read Error in %s\n", file);
 547             ERR_print_errors(bio_err);
 548             goto end;
 549         }
 550         if (i == 0)
 551             break;
 552     }
 553     if (sigin != NULL) {
 554         EVP_MD_CTX *ctx;
 555         BIO_get_md_ctx(bp, &ctx);
 556         i = EVP_DigestVerifyFinal(ctx, sigin, (unsigned int)siglen);
 557         if (i > 0) {
 558             BIO_printf(out, "Verified OK\n");
 559         } else if (i == 0) {
 560             BIO_printf(out, "Verification Failure\n");
 561             goto end;
 562         } else {
 563             BIO_printf(bio_err, "Error Verifying Data\n");
 564             ERR_print_errors(bio_err);
 565             goto end;
 566         }
 567         ret = 0;
 568         goto end;
 569     }
 570     if (key != NULL) {
 571         EVP_MD_CTX *ctx;
 572         size_t tmplen;
 573
 574         BIO_get_md_ctx(bp, &ctx);
 575         if (!EVP_DigestSignFinal(ctx, NULL, &tmplen)) {
 576             BIO_printf(bio_err, "Error Signing Data\n");
 577             ERR_print_errors(bio_err);
 578             goto end;
 579         }
 580         if (tmplen > BUFSIZE) {
 581             len = tmplen;
 582             allocated_buf = app_malloc(len, "Signature buffer");
 583             buf = allocated_buf;
 584         }
 585         if (!EVP_DigestSignFinal(ctx, buf, &len)) {
 586             BIO_printf(bio_err, "Error Signing Data\n");
 587             ERR_print_errors(bio_err);
 588             goto end;
 589         }
 590     } else if (xoflen > 0) {
 591         EVP_MD_CTX *ctx;
 592
 593         len = xoflen;
 594         if (len > BUFSIZE) {
 595             allocated_buf = app_malloc(len, "Digest buffer");
 596             buf = allocated_buf;
 597         }
 598
 599         BIO_get_md_ctx(bp, &ctx);
 600
 601         if (!EVP_DigestFinalXOF(ctx, buf, len)) {
 602             BIO_printf(bio_err, "Error Digesting Data\n");
 603             ERR_print_errors(bio_err);
 604             goto end;
 605         }
 606     } else {
 607         len = BIO_gets(bp, (char *)buf, BUFSIZE);
 608         if ((int)len < 0) {
 609             ERR_print_errors(bio_err);
 610             goto end;
 611         }
 612     }
 613
 614     if (binout) {
 615         BIO_write(out, buf, len);
 616     } else if (sep == 2) {
 617         file = newline_escape_filename(file, &backslash);
 618
 619         if (backslash == 1)
 620             BIO_puts(out, "\\");
 621
 622         for (i = 0; i < (int)len; i++)
 623             BIO_printf(out, "%02x", buf[i]);
 624
 625         BIO_printf(out, " *%s\n", file);
 626         OPENSSL_free((char *)file);
 627     } else {
 628         if (sig_name != NULL) {
 629             BIO_puts(out, sig_name);
 630             if (md_name != NULL)
 631                 BIO_printf(out, "-%s", md_name);
 632             BIO_printf(out, "(%s)= ", file);
 633         } else if (md_name != NULL) {
 634             BIO_printf(out, "%s(%s)= ", md_name, file);
 635         } else {
 636             BIO_printf(out, "(%s)= ", file);
 637         }
 638         for (i = 0; i < (int)len; i++) {
 639             if (sep && (i != 0))
 640                 BIO_printf(out, ":");
 641             BIO_printf(out, "%02x", buf[i]);
 642         }
 643         BIO_printf(out, "\n");
 644     }
 645
 646     ret = 0;
 647  end:
 648     if (allocated_buf != NULL)
 649         OPENSSL_clear_free(allocated_buf, len);
 650
 651     return ret;
 652 }