apps/smime.c

   1 /*
   2  * Copyright 1999-2018 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 /* S/MIME utility function */
  11
  12 #include <stdio.h>
  13 #include <string.h>
  14 #include "apps.h"
  15 #include "progs.h"
  16 #include <openssl/crypto.h>
  17 #include <openssl/pem.h>
  18 #include <openssl/err.h>
  19 #include <openssl/x509_vfy.h>
  20 #include <openssl/x509v3.h>
  21
  22 static int save_certs(char *signerfile, STACK_OF(X509) *signers);
  23 static int smime_cb(int ok, X509_STORE_CTX *ctx);
  24
  25 #define SMIME_OP        0x10
  26 #define SMIME_IP        0x20
  27 #define SMIME_SIGNERS   0x40
  28 #define SMIME_ENCRYPT   (1 | SMIME_OP)
  29 #define SMIME_DECRYPT   (2 | SMIME_IP)
  30 #define SMIME_SIGN      (3 | SMIME_OP | SMIME_SIGNERS)
  31 #define SMIME_VERIFY    (4 | SMIME_IP)
  32 #define SMIME_PK7OUT    (5 | SMIME_IP | SMIME_OP)
  33 #define SMIME_RESIGN    (6 | SMIME_IP | SMIME_OP | SMIME_SIGNERS)
  34
  35 typedef enum OPTION_choice {
  36     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  37     OPT_ENCRYPT, OPT_DECRYPT, OPT_SIGN, OPT_RESIGN, OPT_VERIFY,
  38     OPT_PK7OUT, OPT_TEXT, OPT_NOINTERN, OPT_NOVERIFY, OPT_NOCHAIN,
  39     OPT_NOCERTS, OPT_NOATTR, OPT_NODETACH, OPT_NOSMIMECAP,
  40     OPT_BINARY, OPT_NOSIGS, OPT_STREAM, OPT_INDEF, OPT_NOINDEF,
  41     OPT_CRLFEOL, OPT_ENGINE, OPT_PASSIN,
  42     OPT_TO, OPT_FROM, OPT_SUBJECT, OPT_SIGNER, OPT_RECIP, OPT_MD,
  43     OPT_CIPHER, OPT_INKEY, OPT_KEYFORM, OPT_CERTFILE, OPT_CAFILE,
  44     OPT_CAPATH, OPT_CASTORE, OPT_NOCAFILE, OPT_NOCAPATH, OPT_NOCASTORE,
  45     OPT_R_ENUM,
  46     OPT_V_ENUM,
  47     OPT_IN, OPT_INFORM, OPT_OUT,
  48     OPT_OUTFORM, OPT_CONTENT
  49 } OPTION_CHOICE;
  50
  51 const OPTIONS smime_options[] = {
  52     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [cert...]\n"},
  53
  54     OPT_SECTION("General"),
  55     {"help", OPT_HELP, '-', "Display this summary"},
  56     {"in", OPT_IN, '<', "Input file"},
  57     {"inform", OPT_INFORM, 'c', "Input format SMIME (default), PEM or DER"},
  58     {"out", OPT_OUT, '>', "Output file"},
  59     {"outform", OPT_OUTFORM, 'c',
  60      "Output format SMIME (default), PEM or DER"},
  61     {"inkey", OPT_INKEY, 's',
  62      "Input private key (if not signer or recipient)"},
  63     {"keyform", OPT_KEYFORM, 'f', "Input private key format (PEM or ENGINE)"},
  64 #ifndef OPENSSL_NO_ENGINE
  65     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
  66 #endif
  67     {"stream", OPT_STREAM, '-', "Enable CMS streaming" },
  68     {"indef", OPT_INDEF, '-', "Same as -stream" },
  69     {"noindef", OPT_NOINDEF, '-', "Disable CMS streaming"},
  70
  71     OPT_SECTION("Action"),
  72     {"encrypt", OPT_ENCRYPT, '-', "Encrypt message"},
  73     {"decrypt", OPT_DECRYPT, '-', "Decrypt encrypted message"},
  74     {"sign", OPT_SIGN, '-', "Sign message"},
  75     {"resign", OPT_RESIGN, '-', "Resign a signed message"},
  76     {"verify", OPT_VERIFY, '-', "Verify signed message"},
  77
  78     OPT_SECTION("Signing/Encryption"),
  79     {"passin", OPT_PASSIN, 's', "Input file pass phrase source"},
  80     {"md", OPT_MD, 's', "Digest algorithm to use when signing or resigning"},
  81     {"", OPT_CIPHER, '-', "Any supported cipher"},
  82     {"pk7out", OPT_PK7OUT, '-', "Output PKCS#7 structure"},
  83     {"nointern", OPT_NOINTERN, '-',
  84      "Don't search certificates in message for signer"},
  85     {"nodetach", OPT_NODETACH, '-', "Use opaque signing"},
  86     {"noattr", OPT_NOATTR, '-', "Don't include any signed attributes"},
  87     {"binary", OPT_BINARY, '-', "Don't translate message to text"},
  88     {"signer", OPT_SIGNER, 's', "Signer certificate file"},
  89     {"content", OPT_CONTENT, '<',
  90      "Supply or override content for detached signature"},
  91     {"nocerts", OPT_NOCERTS, '-',
  92      "Don't include signers certificate when signing"},
  93
  94     OPT_SECTION("Verification/Decryption"),
  95     {"nosigs", OPT_NOSIGS, '-', "Don't verify message signature"},
  96     {"noverify", OPT_NOVERIFY, '-', "Don't verify signers certificate"},
  97
  98     {"certfile", OPT_CERTFILE, '<', "Other certificates file"},
  99     {"recip", OPT_RECIP, '<', "Recipient certificate file for decryption"},
 100
 101     OPT_SECTION("Email"),
 102     {"to", OPT_TO, 's', "To address"},
 103     {"from", OPT_FROM, 's', "From address"},
 104     {"subject", OPT_SUBJECT, 's', "Subject"},
 105     {"text", OPT_TEXT, '-', "Include or delete text MIME headers"},
 106     {"nosmimecap", OPT_NOSMIMECAP, '-', "Omit the SMIMECapabilities attribute"},
 107
 108     OPT_SECTION("Certificate chain"),
 109     {"CApath", OPT_CAPATH, '/', "Trusted certificates directory"},
 110     {"CAfile", OPT_CAFILE, '<', "Trusted certificates file"},
 111     {"CAstore", OPT_CASTORE, ':', "Trusted certificates store URI"},
 112     {"no-CAfile", OPT_NOCAFILE, '-',
 113      "Do not load the default certificates file"},
 114     {"no-CApath", OPT_NOCAPATH, '-',
 115      "Do not load certificates from the default certificates directory"},
 116     {"no-CAstore", OPT_NOCASTORE, '-',
 117      "Do not load certificates from the default certificates store"},
 118     {"nochain", OPT_NOCHAIN, '-',
 119      "set PKCS7_NOCHAIN so certificates contained in the message are not used as untrusted CAs" },
 120     {"crlfeol", OPT_CRLFEOL, '-', "Use CRLF as EOL termination instead of CR only"},
 121
 122     OPT_R_OPTIONS,
 123     OPT_V_OPTIONS,
 124
 125     OPT_PARAMETERS(),
 126     {"cert", 0, 0, "Recipient certs, used when encrypting"},
 127     {NULL}
 128 };
 129
 130 int smime_main(int argc, char **argv)
 131 {
 132     BIO *in = NULL, *out = NULL, *indata = NULL;
 133     EVP_PKEY *key = NULL;
 134     PKCS7 *p7 = NULL;
 135     STACK_OF(OPENSSL_STRING) *sksigners = NULL, *skkeys = NULL;
 136     STACK_OF(X509) *encerts = NULL, *other = NULL;
 137     X509 *cert = NULL, *recip = NULL, *signer = NULL;
 138     X509_STORE *store = NULL;
 139     X509_VERIFY_PARAM *vpm = NULL;
 140     const EVP_CIPHER *cipher = NULL;
 141     const EVP_MD *sign_md = NULL;
 142     const char *CAfile = NULL, *CApath = NULL, *CAstore = NULL, *prog = NULL;
 143     char *certfile = NULL, *keyfile = NULL, *contfile = NULL;
 144     char *infile = NULL, *outfile = NULL, *signerfile = NULL, *recipfile = NULL;
 145     char *passinarg = NULL, *passin = NULL, *to = NULL, *from = NULL, *subject = NULL;
 146     OPTION_CHOICE o;
 147     int noCApath = 0, noCAfile = 0, noCAstore = 0;
 148     int flags = PKCS7_DETACHED, operation = 0, ret = 0, indef = 0;
 149     int informat = FORMAT_SMIME, outformat = FORMAT_SMIME, keyform =
 150         FORMAT_PEM;
 151     int vpmtouched = 0, rv = 0;
 152     ENGINE *e = NULL;
 153     const char *mime_eol = "\n";
 154
 155     if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
 156         return 1;
 157
 158     prog = opt_init(argc, argv, smime_options);
 159     while ((o = opt_next()) != OPT_EOF) {
 160         switch (o) {
 161         case OPT_EOF:
 162         case OPT_ERR:
 163  opthelp:
 164             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
 165             goto end;
 166         case OPT_HELP:
 167             opt_help(smime_options);
 168             ret = 0;
 169             goto end;
 170         case OPT_INFORM:
 171             if (!opt_format(opt_arg(), OPT_FMT_PDS, &informat))
 172                 goto opthelp;
 173             break;
 174         case OPT_IN:
 175             infile = opt_arg();
 176             break;
 177         case OPT_OUTFORM:
 178             if (!opt_format(opt_arg(), OPT_FMT_PDS, &outformat))
 179                 goto opthelp;
 180             break;
 181         case OPT_OUT:
 182             outfile = opt_arg();
 183             break;
 184         case OPT_ENCRYPT:
 185             operation = SMIME_ENCRYPT;
 186             break;
 187         case OPT_DECRYPT:
 188             operation = SMIME_DECRYPT;
 189             break;
 190         case OPT_SIGN:
 191             operation = SMIME_SIGN;
 192             break;
 193         case OPT_RESIGN:
 194             operation = SMIME_RESIGN;
 195             break;
 196         case OPT_VERIFY:
 197             operation = SMIME_VERIFY;
 198             break;
 199         case OPT_PK7OUT:
 200             operation = SMIME_PK7OUT;
 201             break;
 202         case OPT_TEXT:
 203             flags |= PKCS7_TEXT;
 204             break;
 205         case OPT_NOINTERN:
 206             flags |= PKCS7_NOINTERN;
 207             break;
 208         case OPT_NOVERIFY:
 209             flags |= PKCS7_NOVERIFY;
 210             break;
 211         case OPT_NOCHAIN:
 212             flags |= PKCS7_NOCHAIN;
 213             break;
 214         case OPT_NOCERTS:
 215             flags |= PKCS7_NOCERTS;
 216             break;
 217         case OPT_NOATTR:
 218             flags |= PKCS7_NOATTR;
 219             break;
 220         case OPT_NODETACH:
 221             flags &= ~PKCS7_DETACHED;
 222             break;
 223         case OPT_NOSMIMECAP:
 224             flags |= PKCS7_NOSMIMECAP;
 225             break;
 226         case OPT_BINARY:
 227             flags |= PKCS7_BINARY;
 228             break;
 229         case OPT_NOSIGS:
 230             flags |= PKCS7_NOSIGS;
 231             break;
 232         case OPT_STREAM:
 233         case OPT_INDEF:
 234             indef = 1;
 235             break;
 236         case OPT_NOINDEF:
 237             indef = 0;
 238             break;
 239         case OPT_CRLFEOL:
 240             flags |= PKCS7_CRLFEOL;
 241             mime_eol = "\r\n";
 242             break;
 243         case OPT_R_CASES:
 244             if (!opt_rand(o))
 245                 goto end;
 246             break;
 247         case OPT_ENGINE:
 248             e = setup_engine(opt_arg(), 0);
 249             break;
 250         case OPT_PASSIN:
 251             passinarg = opt_arg();
 252             break;
 253         case OPT_TO:
 254             to = opt_arg();
 255             break;
 256         case OPT_FROM:
 257             from = opt_arg();
 258             break;
 259         case OPT_SUBJECT:
 260             subject = opt_arg();
 261             break;
 262         case OPT_SIGNER:
 263             /* If previous -signer argument add signer to list */
 264             if (signerfile != NULL) {
 265                 if (sksigners == NULL
 266                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 267                     goto end;
 268                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 269                 if (keyfile == NULL)
 270                     keyfile = signerfile;
 271                 if (skkeys == NULL
 272                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 273                     goto end;
 274                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 275                 keyfile = NULL;
 276             }
 277             signerfile = opt_arg();
 278             break;
 279         case OPT_RECIP:
 280             recipfile = opt_arg();
 281             break;
 282         case OPT_MD:
 283             if (!opt_md(opt_arg(), &sign_md))
 284                 goto opthelp;
 285             break;
 286         case OPT_CIPHER:
 287             if (!opt_cipher(opt_unknown(), &cipher))
 288                 goto opthelp;
 289             break;
 290         case OPT_INKEY:
 291             /* If previous -inkey argument add signer to list */
 292             if (keyfile != NULL) {
 293                 if (signerfile == NULL) {
 294                     BIO_printf(bio_err,
 295                                "%s: Must have -signer before -inkey\n", prog);
 296                     goto opthelp;
 297                 }
 298                 if (sksigners == NULL
 299                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 300                     goto end;
 301                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 302                 signerfile = NULL;
 303                 if (skkeys == NULL
 304                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 305                     goto end;
 306                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 307             }
 308             keyfile = opt_arg();
 309             break;
 310         case OPT_KEYFORM:
 311             if (!opt_format(opt_arg(), OPT_FMT_ANY, &keyform))
 312                 goto opthelp;
 313             break;
 314         case OPT_CERTFILE:
 315             certfile = opt_arg();
 316             break;
 317         case OPT_CAFILE:
 318             CAfile = opt_arg();
 319             break;
 320         case OPT_CAPATH:
 321             CApath = opt_arg();
 322             break;
 323         case OPT_CASTORE:
 324             CAstore = opt_arg();
 325             break;
 326         case OPT_NOCAFILE:
 327             noCAfile = 1;
 328             break;
 329         case OPT_NOCAPATH:
 330             noCApath = 1;
 331             break;
 332         case OPT_NOCASTORE:
 333             noCAstore = 1;
 334             break;
 335         case OPT_CONTENT:
 336             contfile = opt_arg();
 337             break;
 338         case OPT_V_CASES:
 339             if (!opt_verify(o, vpm))
 340                 goto opthelp;
 341             vpmtouched++;
 342             break;
 343         }
 344     }
 345     argc = opt_num_rest();
 346     argv = opt_rest();
 347
 348     if (!(operation & SMIME_SIGNERS) && (skkeys != NULL || sksigners != NULL)) {
 349         BIO_puts(bio_err, "Multiple signers or keys not allowed\n");
 350         goto opthelp;
 351     }
 352
 353     if (operation & SMIME_SIGNERS) {
 354         /* Check to see if any final signer needs to be appended */
 355         if (keyfile && !signerfile) {
 356             BIO_puts(bio_err, "Illegal -inkey without -signer\n");
 357             goto opthelp;
 358         }
 359         if (signerfile != NULL) {
 360             if (sksigners == NULL
 361                 && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 362                 goto end;
 363             sk_OPENSSL_STRING_push(sksigners, signerfile);
 364             if (!skkeys && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 365                 goto end;
 366             if (!keyfile)
 367                 keyfile = signerfile;
 368             sk_OPENSSL_STRING_push(skkeys, keyfile);
 369         }
 370         if (sksigners == NULL) {
 371             BIO_printf(bio_err, "No signer certificate specified\n");
 372             goto opthelp;
 373         }
 374         signerfile = NULL;
 375         keyfile = NULL;
 376     } else if (operation == SMIME_DECRYPT) {
 377         if (recipfile == NULL && keyfile == NULL) {
 378             BIO_printf(bio_err,
 379                        "No recipient certificate or key specified\n");
 380             goto opthelp;
 381         }
 382     } else if (operation == SMIME_ENCRYPT) {
 383         if (argc == 0) {
 384             BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
 385             goto opthelp;
 386         }
 387     } else if (!operation) {
 388         goto opthelp;
 389     }
 390
 391     if (!app_passwd(passinarg, NULL, &passin, NULL)) {
 392         BIO_printf(bio_err, "Error getting password\n");
 393         goto end;
 394     }
 395
 396     ret = 2;
 397
 398     if (!(operation & SMIME_SIGNERS))
 399         flags &= ~PKCS7_DETACHED;
 400
 401     if (!(operation & SMIME_OP)) {
 402         if (flags & PKCS7_BINARY)
 403             outformat = FORMAT_BINARY;
 404     }
 405
 406     if (!(operation & SMIME_IP)) {
 407         if (flags & PKCS7_BINARY)
 408             informat = FORMAT_BINARY;
 409     }
 410
 411     if (operation == SMIME_ENCRYPT) {
 412         if (cipher == NULL) {
 413 #ifndef OPENSSL_NO_DES
 414             cipher = EVP_des_ede3_cbc();
 415 #else
 416             BIO_printf(bio_err, "No cipher selected\n");
 417             goto end;
 418 #endif
 419         }
 420         encerts = sk_X509_new_null();
 421         if (encerts == NULL)
 422             goto end;
 423         while (*argv != NULL) {
 424             cert = load_cert(*argv, FORMAT_PEM,
 425                              "recipient certificate file");
 426             if (cert == NULL)
 427                 goto end;
 428             sk_X509_push(encerts, cert);
 429             cert = NULL;
 430             argv++;
 431         }
 432     }
 433
 434     if (certfile != NULL) {
 435         if (!load_certs(certfile, &other, FORMAT_PEM, NULL,
 436                         "certificate file")) {
 437             ERR_print_errors(bio_err);
 438             goto end;
 439         }
 440     }
 441
 442     if (recipfile != NULL && (operation == SMIME_DECRYPT)) {
 443         if ((recip = load_cert(recipfile, FORMAT_PEM,
 444                                "recipient certificate file")) == NULL) {
 445             ERR_print_errors(bio_err);
 446             goto end;
 447         }
 448     }
 449
 450     if (operation == SMIME_DECRYPT) {
 451         if (keyfile == NULL)
 452             keyfile = recipfile;
 453     } else if (operation == SMIME_SIGN) {
 454         if (keyfile == NULL)
 455             keyfile = signerfile;
 456     } else {
 457         keyfile = NULL;
 458     }
 459
 460     if (keyfile != NULL) {
 461         key = load_key(keyfile, keyform, 0, passin, e, "signing key file");
 462         if (key == NULL)
 463             goto end;
 464     }
 465
 466     in = bio_open_default(infile, 'r', informat);
 467     if (in == NULL)
 468         goto end;
 469
 470     if (operation & SMIME_IP) {
 471         if (informat == FORMAT_SMIME) {
 472             p7 = SMIME_read_PKCS7(in, &indata);
 473         } else if (informat == FORMAT_PEM) {
 474             p7 = PEM_read_bio_PKCS7(in, NULL, NULL, NULL);
 475         } else if (informat == FORMAT_ASN1) {
 476             p7 = d2i_PKCS7_bio(in, NULL);
 477         } else {
 478             BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
 479             goto end;
 480         }
 481
 482         if (p7 == NULL) {
 483             BIO_printf(bio_err, "Error reading S/MIME message\n");
 484             goto end;
 485         }
 486         if (contfile != NULL) {
 487             BIO_free(indata);
 488             if ((indata = BIO_new_file(contfile, "rb")) == NULL) {
 489                 BIO_printf(bio_err, "Can't read content file %s\n", contfile);
 490                 goto end;
 491             }
 492         }
 493     }
 494
 495     out = bio_open_default(outfile, 'w', outformat);
 496     if (out == NULL)
 497         goto end;
 498
 499     if (operation == SMIME_VERIFY) {
 500         if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
 501                                   CAstore, noCAstore)) == NULL)
 502             goto end;
 503         X509_STORE_set_verify_cb(store, smime_cb);
 504         if (vpmtouched)
 505             X509_STORE_set1_param(store, vpm);
 506     }
 507
 508     ret = 3;
 509
 510     if (operation == SMIME_ENCRYPT) {
 511         if (indef)
 512             flags |= PKCS7_STREAM;
 513         p7 = PKCS7_encrypt(encerts, in, cipher, flags);
 514     } else if (operation & SMIME_SIGNERS) {
 515         int i;
 516         /*
 517          * If detached data content we only enable streaming if S/MIME output
 518          * format.
 519          */
 520         if (operation == SMIME_SIGN) {
 521             if (flags & PKCS7_DETACHED) {
 522                 if (outformat == FORMAT_SMIME)
 523                     flags |= PKCS7_STREAM;
 524             } else if (indef) {
 525                 flags |= PKCS7_STREAM;
 526             }
 527             flags |= PKCS7_PARTIAL;
 528             p7 = PKCS7_sign(NULL, NULL, other, in, flags);
 529             if (p7 == NULL)
 530                 goto end;
 531             if (flags & PKCS7_NOCERTS) {
 532                 for (i = 0; i < sk_X509_num(other); i++) {
 533                     X509 *x = sk_X509_value(other, i);
 534                     PKCS7_add_certificate(p7, x);
 535                 }
 536             }
 537         } else {
 538             flags |= PKCS7_REUSE_DIGEST;
 539         }
 540         for (i = 0; i < sk_OPENSSL_STRING_num(sksigners); i++) {
 541             signerfile = sk_OPENSSL_STRING_value(sksigners, i);
 542             keyfile = sk_OPENSSL_STRING_value(skkeys, i);
 543             signer = load_cert(signerfile, FORMAT_PEM,
 544                                "signer certificate");
 545             if (signer == NULL)
 546                 goto end;
 547             key = load_key(keyfile, keyform, 0, passin, e, "signing key file");
 548             if (key == NULL)
 549                 goto end;
 550             if (!PKCS7_sign_add_signer(p7, signer, key, sign_md, flags))
 551                 goto end;
 552             X509_free(signer);
 553             signer = NULL;
 554             EVP_PKEY_free(key);
 555             key = NULL;
 556         }
 557         /* If not streaming or resigning finalize structure */
 558         if ((operation == SMIME_SIGN) && !(flags & PKCS7_STREAM)) {
 559             if (!PKCS7_final(p7, in, flags))
 560                 goto end;
 561         }
 562     }
 563
 564     if (p7 == NULL) {
 565         BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
 566         goto end;
 567     }
 568
 569     ret = 4;
 570     if (operation == SMIME_DECRYPT) {
 571         if (!PKCS7_decrypt(p7, key, recip, out, flags)) {
 572             BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
 573             goto end;
 574         }
 575     } else if (operation == SMIME_VERIFY) {
 576         STACK_OF(X509) *signers;
 577         if (PKCS7_verify(p7, other, store, indata, out, flags))
 578             BIO_printf(bio_err, "Verification successful\n");
 579         else {
 580             BIO_printf(bio_err, "Verification failure\n");
 581             goto end;
 582         }
 583         signers = PKCS7_get0_signers(p7, other, flags);
 584         if (!save_certs(signerfile, signers)) {
 585             BIO_printf(bio_err, "Error writing signers to %s\n", signerfile);
 586             ret = 5;
 587             goto end;
 588         }
 589         sk_X509_free(signers);
 590     } else if (operation == SMIME_PK7OUT) {
 591         PEM_write_bio_PKCS7(out, p7);
 592     } else {
 593         if (to)
 594             BIO_printf(out, "To: %s%s", to, mime_eol);
 595         if (from)
 596             BIO_printf(out, "From: %s%s", from, mime_eol);
 597         if (subject)
 598             BIO_printf(out, "Subject: %s%s", subject, mime_eol);
 599         if (outformat == FORMAT_SMIME) {
 600             if (operation == SMIME_RESIGN)
 601                 rv = SMIME_write_PKCS7(out, p7, indata, flags);
 602             else
 603                 rv = SMIME_write_PKCS7(out, p7, in, flags);
 604         } else if (outformat == FORMAT_PEM) {
 605             rv = PEM_write_bio_PKCS7_stream(out, p7, in, flags);
 606         } else if (outformat == FORMAT_ASN1) {
 607             rv = i2d_PKCS7_bio_stream(out, p7, in, flags);
 608         } else {
 609             BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
 610             goto end;
 611         }
 612         if (rv == 0) {
 613             BIO_printf(bio_err, "Error writing output\n");
 614             ret = 3;
 615             goto end;
 616         }
 617     }
 618     ret = 0;
 619  end:
 620     if (ret)
 621         ERR_print_errors(bio_err);
 622     sk_X509_pop_free(encerts, X509_free);
 623     sk_X509_pop_free(other, X509_free);
 624     X509_VERIFY_PARAM_free(vpm);
 625     sk_OPENSSL_STRING_free(sksigners);
 626     sk_OPENSSL_STRING_free(skkeys);
 627     X509_STORE_free(store);
 628     X509_free(cert);
 629     X509_free(recip);
 630     X509_free(signer);
 631     EVP_PKEY_free(key);
 632     PKCS7_free(p7);
 633     release_engine(e);
 634     BIO_free(in);
 635     BIO_free(indata);
 636     BIO_free_all(out);
 637     OPENSSL_free(passin);
 638     return ret;
 639 }
 640
 641 static int save_certs(char *signerfile, STACK_OF(X509) *signers)
 642 {
 643     int i;
 644     BIO *tmp;
 645
 646     if (signerfile == NULL)
 647         return 1;
 648     tmp = BIO_new_file(signerfile, "w");
 649     if (tmp == NULL)
 650         return 0;
 651     for (i = 0; i < sk_X509_num(signers); i++)
 652         PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
 653     BIO_free(tmp);
 654     return 1;
 655 }
 656
 657 /* Minimal callback just to output policy info (if any) */
 658
 659 static int smime_cb(int ok, X509_STORE_CTX *ctx)
 660 {
 661     int error;
 662
 663     error = X509_STORE_CTX_get_error(ctx);
 664
 665     if ((error != X509_V_ERR_NO_EXPLICIT_POLICY)
 666         && ((error != X509_V_OK) || (ok != 2)))
 667         return ok;
 668
 669     policies_print(ctx);
 670
 671     return ok;
 672 }