apps/smime.c

   1 /*
   2  * Copyright 1999-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /* 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 DEFINE_STACK_OF(X509)
  23 DEFINE_STACK_OF_STRING()
  24
  25 static int save_certs(char *signerfile, STACK_OF(X509) *signers);
  26 static int smime_cb(int ok, X509_STORE_CTX *ctx);
  27
  28 #define SMIME_OP        0x10
  29 #define SMIME_IP        0x20
  30 #define SMIME_SIGNERS   0x40
  31 #define SMIME_ENCRYPT   (1 | SMIME_OP)
  32 #define SMIME_DECRYPT   (2 | SMIME_IP)
  33 #define SMIME_SIGN      (3 | SMIME_OP | SMIME_SIGNERS)
  34 #define SMIME_VERIFY    (4 | SMIME_IP)
  35 #define SMIME_PK7OUT    (5 | SMIME_IP | SMIME_OP)
  36 #define SMIME_RESIGN    (6 | SMIME_IP | SMIME_OP | SMIME_SIGNERS)
  37
  38 typedef enum OPTION_choice {
  39     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  40     OPT_ENCRYPT, OPT_DECRYPT, OPT_SIGN, OPT_RESIGN, OPT_VERIFY,
  41     OPT_PK7OUT, OPT_TEXT, OPT_NOINTERN, OPT_NOVERIFY, OPT_NOCHAIN,
  42     OPT_NOCERTS, OPT_NOATTR, OPT_NODETACH, OPT_NOSMIMECAP,
  43     OPT_BINARY, OPT_NOSIGS, OPT_STREAM, OPT_INDEF, OPT_NOINDEF,
  44     OPT_CRLFEOL, OPT_ENGINE, OPT_PASSIN,
  45     OPT_TO, OPT_FROM, OPT_SUBJECT, OPT_SIGNER, OPT_RECIP, OPT_MD,
  46     OPT_CIPHER, OPT_INKEY, OPT_KEYFORM, OPT_CERTFILE, OPT_CAFILE,
  47     OPT_CAPATH, OPT_CASTORE, OPT_NOCAFILE, OPT_NOCAPATH, OPT_NOCASTORE,
  48     OPT_R_ENUM, OPT_PROV_ENUM,
  49     OPT_V_ENUM,
  50     OPT_IN, OPT_INFORM, OPT_OUT,
  51     OPT_OUTFORM, OPT_CONTENT
  52 } OPTION_CHOICE;
  53
  54 const OPTIONS smime_options[] = {
  55     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [cert...]\n"},
  56
  57     OPT_SECTION("General"),
  58     {"help", OPT_HELP, '-', "Display this summary"},
  59     {"in", OPT_IN, '<', "Input file"},
  60     {"inform", OPT_INFORM, 'c', "Input format SMIME (default), PEM or DER"},
  61     {"out", OPT_OUT, '>', "Output file"},
  62     {"outform", OPT_OUTFORM, 'c',
  63      "Output format SMIME (default), PEM or DER"},
  64     {"inkey", OPT_INKEY, 's',
  65      "Input private key (if not signer or recipient)"},
  66     {"keyform", OPT_KEYFORM, 'f', "Input private key format (ENGINE, other values ignored)"},
  67 #ifndef OPENSSL_NO_ENGINE
  68     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
  69 #endif
  70     {"stream", OPT_STREAM, '-', "Enable CMS streaming" },
  71     {"indef", OPT_INDEF, '-', "Same as -stream" },
  72     {"noindef", OPT_NOINDEF, '-', "Disable CMS streaming"},
  73
  74     OPT_SECTION("Action"),
  75     {"encrypt", OPT_ENCRYPT, '-', "Encrypt message"},
  76     {"decrypt", OPT_DECRYPT, '-', "Decrypt encrypted message"},
  77     {"sign", OPT_SIGN, '-', "Sign message"},
  78     {"resign", OPT_RESIGN, '-', "Resign a signed message"},
  79     {"verify", OPT_VERIFY, '-', "Verify signed message"},
  80
  81     OPT_SECTION("Signing/Encryption"),
  82     {"passin", OPT_PASSIN, 's', "Input file pass phrase source"},
  83     {"md", OPT_MD, 's', "Digest algorithm to use when signing or resigning"},
  84     {"", OPT_CIPHER, '-', "Any supported cipher"},
  85     {"pk7out", OPT_PK7OUT, '-', "Output PKCS#7 structure"},
  86     {"nointern", OPT_NOINTERN, '-',
  87      "Don't search certificates in message for signer"},
  88     {"nodetach", OPT_NODETACH, '-', "Use opaque signing"},
  89     {"noattr", OPT_NOATTR, '-', "Don't include any signed attributes"},
  90     {"binary", OPT_BINARY, '-', "Don't translate message to text"},
  91     {"signer", OPT_SIGNER, 's', "Signer certificate file"},
  92     {"content", OPT_CONTENT, '<',
  93      "Supply or override content for detached signature"},
  94     {"nocerts", OPT_NOCERTS, '-',
  95      "Don't include signers certificate when signing"},
  96
  97     OPT_SECTION("Verification/Decryption"),
  98     {"nosigs", OPT_NOSIGS, '-', "Don't verify message signature"},
  99     {"noverify", OPT_NOVERIFY, '-', "Don't verify signers certificate"},
 100
 101     {"certfile", OPT_CERTFILE, '<', "Other certificates file"},
 102     {"recip", OPT_RECIP, '<', "Recipient certificate file for decryption"},
 103
 104     OPT_SECTION("Email"),
 105     {"to", OPT_TO, 's', "To address"},
 106     {"from", OPT_FROM, 's', "From address"},
 107     {"subject", OPT_SUBJECT, 's', "Subject"},
 108     {"text", OPT_TEXT, '-', "Include or delete text MIME headers"},
 109     {"nosmimecap", OPT_NOSMIMECAP, '-', "Omit the SMIMECapabilities attribute"},
 110
 111     OPT_SECTION("Certificate chain"),
 112     {"CApath", OPT_CAPATH, '/', "Trusted certificates directory"},
 113     {"CAfile", OPT_CAFILE, '<', "Trusted certificates file"},
 114     {"CAstore", OPT_CASTORE, ':', "Trusted certificates store URI"},
 115     {"no-CAfile", OPT_NOCAFILE, '-',
 116      "Do not load the default certificates file"},
 117     {"no-CApath", OPT_NOCAPATH, '-',
 118      "Do not load certificates from the default certificates directory"},
 119     {"no-CAstore", OPT_NOCASTORE, '-',
 120      "Do not load certificates from the default certificates store"},
 121     {"nochain", OPT_NOCHAIN, '-',
 122      "set PKCS7_NOCHAIN so certificates contained in the message are not used as untrusted CAs" },
 123     {"crlfeol", OPT_CRLFEOL, '-', "Use CRLF as EOL termination instead of CR only"},
 124
 125     OPT_R_OPTIONS,
 126     OPT_V_OPTIONS,
 127     OPT_PROV_OPTIONS,
 128
 129     OPT_PARAMETERS(),
 130     {"cert", 0, 0, "Recipient certs, used when encrypting"},
 131     {NULL}
 132 };
 133
 134 int smime_main(int argc, char **argv)
 135 {
 136     BIO *in = NULL, *out = NULL, *indata = NULL;
 137     EVP_PKEY *key = NULL;
 138     PKCS7 *p7 = NULL;
 139     STACK_OF(OPENSSL_STRING) *sksigners = NULL, *skkeys = NULL;
 140     STACK_OF(X509) *encerts = NULL, *other = NULL;
 141     X509 *cert = NULL, *recip = NULL, *signer = NULL;
 142     X509_STORE *store = NULL;
 143     X509_VERIFY_PARAM *vpm = NULL;
 144     const EVP_CIPHER *cipher = NULL;
 145     const EVP_MD *sign_md = NULL;
 146     const char *CAfile = NULL, *CApath = NULL, *CAstore = NULL, *prog = NULL;
 147     char *certfile = NULL, *keyfile = NULL, *contfile = NULL;
 148     char *infile = NULL, *outfile = NULL, *signerfile = NULL, *recipfile = NULL;
 149     char *passinarg = NULL, *passin = NULL, *to = NULL, *from = NULL, *subject = NULL;
 150     OPTION_CHOICE o;
 151     int noCApath = 0, noCAfile = 0, noCAstore = 0;
 152     int flags = PKCS7_DETACHED, operation = 0, ret = 0, indef = 0;
 153     int informat = FORMAT_SMIME, outformat = FORMAT_SMIME, keyform =
 154         FORMAT_PEM;
 155     int vpmtouched = 0, rv = 0;
 156     ENGINE *e = NULL;
 157     const char *mime_eol = "\n";
 158
 159     if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
 160         return 1;
 161
 162     prog = opt_init(argc, argv, smime_options);
 163     while ((o = opt_next()) != OPT_EOF) {
 164         switch (o) {
 165         case OPT_EOF:
 166         case OPT_ERR:
 167  opthelp:
 168             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
 169             goto end;
 170         case OPT_HELP:
 171             opt_help(smime_options);
 172             ret = 0;
 173             goto end;
 174         case OPT_INFORM:
 175             if (!opt_format(opt_arg(), OPT_FMT_PDS, &informat))
 176                 goto opthelp;
 177             break;
 178         case OPT_IN:
 179             infile = opt_arg();
 180             break;
 181         case OPT_OUTFORM:
 182             if (!opt_format(opt_arg(), OPT_FMT_PDS, &outformat))
 183                 goto opthelp;
 184             break;
 185         case OPT_OUT:
 186             outfile = opt_arg();
 187             break;
 188         case OPT_ENCRYPT:
 189             operation = SMIME_ENCRYPT;
 190             break;
 191         case OPT_DECRYPT:
 192             operation = SMIME_DECRYPT;
 193             break;
 194         case OPT_SIGN:
 195             operation = SMIME_SIGN;
 196             break;
 197         case OPT_RESIGN:
 198             operation = SMIME_RESIGN;
 199             break;
 200         case OPT_VERIFY:
 201             operation = SMIME_VERIFY;
 202             break;
 203         case OPT_PK7OUT:
 204             operation = SMIME_PK7OUT;
 205             break;
 206         case OPT_TEXT:
 207             flags |= PKCS7_TEXT;
 208             break;
 209         case OPT_NOINTERN:
 210             flags |= PKCS7_NOINTERN;
 211             break;
 212         case OPT_NOVERIFY:
 213             flags |= PKCS7_NOVERIFY;
 214             break;
 215         case OPT_NOCHAIN:
 216             flags |= PKCS7_NOCHAIN;
 217             break;
 218         case OPT_NOCERTS:
 219             flags |= PKCS7_NOCERTS;
 220             break;
 221         case OPT_NOATTR:
 222             flags |= PKCS7_NOATTR;
 223             break;
 224         case OPT_NODETACH:
 225             flags &= ~PKCS7_DETACHED;
 226             break;
 227         case OPT_NOSMIMECAP:
 228             flags |= PKCS7_NOSMIMECAP;
 229             break;
 230         case OPT_BINARY:
 231             flags |= PKCS7_BINARY;
 232             break;
 233         case OPT_NOSIGS:
 234             flags |= PKCS7_NOSIGS;
 235             break;
 236         case OPT_STREAM:
 237         case OPT_INDEF:
 238             indef = 1;
 239             break;
 240         case OPT_NOINDEF:
 241             indef = 0;
 242             break;
 243         case OPT_CRLFEOL:
 244             flags |= PKCS7_CRLFEOL;
 245             mime_eol = "\r\n";
 246             break;
 247         case OPT_R_CASES:
 248             if (!opt_rand(o))
 249                 goto end;
 250             break;
 251         case OPT_PROV_CASES:
 252             if (!opt_provider(o))
 253                 goto end;
 254             break;
 255         case OPT_ENGINE:
 256             e = setup_engine(opt_arg(), 0);
 257             break;
 258         case OPT_PASSIN:
 259             passinarg = opt_arg();
 260             break;
 261         case OPT_TO:
 262             to = opt_arg();
 263             break;
 264         case OPT_FROM:
 265             from = opt_arg();
 266             break;
 267         case OPT_SUBJECT:
 268             subject = opt_arg();
 269             break;
 270         case OPT_SIGNER:
 271             /* If previous -signer argument add signer to list */
 272             if (signerfile != NULL) {
 273                 if (sksigners == NULL
 274                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 275                     goto end;
 276                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 277                 if (keyfile == NULL)
 278                     keyfile = signerfile;
 279                 if (skkeys == NULL
 280                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 281                     goto end;
 282                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 283                 keyfile = NULL;
 284             }
 285             signerfile = opt_arg();
 286             break;
 287         case OPT_RECIP:
 288             recipfile = opt_arg();
 289             break;
 290         case OPT_MD:
 291             if (!opt_md(opt_arg(), &sign_md))
 292                 goto opthelp;
 293             break;
 294         case OPT_CIPHER:
 295             if (!opt_cipher(opt_unknown(), &cipher))
 296                 goto opthelp;
 297             break;
 298         case OPT_INKEY:
 299             /* If previous -inkey argument add signer to list */
 300             if (keyfile != NULL) {
 301                 if (signerfile == NULL) {
 302                     BIO_printf(bio_err,
 303                                "%s: Must have -signer before -inkey\n", prog);
 304                     goto opthelp;
 305                 }
 306                 if (sksigners == NULL
 307                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 308                     goto end;
 309                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 310                 signerfile = NULL;
 311                 if (skkeys == NULL
 312                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 313                     goto end;
 314                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 315             }
 316             keyfile = opt_arg();
 317             break;
 318         case OPT_KEYFORM:
 319             if (!opt_format(opt_arg(), OPT_FMT_ANY, &keyform))
 320                 goto opthelp;
 321             break;
 322         case OPT_CERTFILE:
 323             certfile = opt_arg();
 324             break;
 325         case OPT_CAFILE:
 326             CAfile = opt_arg();
 327             break;
 328         case OPT_CAPATH:
 329             CApath = opt_arg();
 330             break;
 331         case OPT_CASTORE:
 332             CAstore = opt_arg();
 333             break;
 334         case OPT_NOCAFILE:
 335             noCAfile = 1;
 336             break;
 337         case OPT_NOCAPATH:
 338             noCApath = 1;
 339             break;
 340         case OPT_NOCASTORE:
 341             noCAstore = 1;
 342             break;
 343         case OPT_CONTENT:
 344             contfile = opt_arg();
 345             break;
 346         case OPT_V_CASES:
 347             if (!opt_verify(o, vpm))
 348                 goto opthelp;
 349             vpmtouched++;
 350             break;
 351         }
 352     }
 353     argc = opt_num_rest();
 354     argv = opt_rest();
 355
 356     if (!(operation & SMIME_SIGNERS) && (skkeys != NULL || sksigners != NULL)) {
 357         BIO_puts(bio_err, "Multiple signers or keys not allowed\n");
 358         goto opthelp;
 359     }
 360
 361     if (operation & SMIME_SIGNERS) {
 362         /* Check to see if any final signer needs to be appended */
 363         if (keyfile && !signerfile) {
 364             BIO_puts(bio_err, "Illegal -inkey without -signer\n");
 365             goto opthelp;
 366         }
 367         if (signerfile != NULL) {
 368             if (sksigners == NULL
 369                 && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 370                 goto end;
 371             sk_OPENSSL_STRING_push(sksigners, signerfile);
 372             if (!skkeys && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 373                 goto end;
 374             if (!keyfile)
 375                 keyfile = signerfile;
 376             sk_OPENSSL_STRING_push(skkeys, keyfile);
 377         }
 378         if (sksigners == NULL) {
 379             BIO_printf(bio_err, "No signer certificate specified\n");
 380             goto opthelp;
 381         }
 382         signerfile = NULL;
 383         keyfile = NULL;
 384     } else if (operation == SMIME_DECRYPT) {
 385         if (recipfile == NULL && keyfile == NULL) {
 386             BIO_printf(bio_err,
 387                        "No recipient certificate or key specified\n");
 388             goto opthelp;
 389         }
 390     } else if (operation == SMIME_ENCRYPT) {
 391         if (argc == 0) {
 392             BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
 393             goto opthelp;
 394         }
 395     } else if (!operation) {
 396         goto opthelp;
 397     }
 398
 399     if (!app_passwd(passinarg, NULL, &passin, NULL)) {
 400         BIO_printf(bio_err, "Error getting password\n");
 401         goto end;
 402     }
 403
 404     ret = 2;
 405
 406     if (!(operation & SMIME_SIGNERS))
 407         flags &= ~PKCS7_DETACHED;
 408
 409     if (!(operation & SMIME_OP)) {
 410         if (flags & PKCS7_BINARY)
 411             outformat = FORMAT_BINARY;
 412     }
 413
 414     if (!(operation & SMIME_IP)) {
 415         if (flags & PKCS7_BINARY)
 416             informat = FORMAT_BINARY;
 417     }
 418
 419     if (operation == SMIME_ENCRYPT) {
 420         if (cipher == NULL) {
 421 #ifndef OPENSSL_NO_DES
 422             cipher = EVP_des_ede3_cbc();
 423 #else
 424             BIO_printf(bio_err, "No cipher selected\n");
 425             goto end;
 426 #endif
 427         }
 428         encerts = sk_X509_new_null();
 429         if (encerts == NULL)
 430             goto end;
 431         while (*argv != NULL) {
 432             cert = load_cert(*argv, FORMAT_UNDEF,
 433                              "recipient certificate file");
 434             if (cert == NULL)
 435                 goto end;
 436             sk_X509_push(encerts, cert);
 437             cert = NULL;
 438             argv++;
 439         }
 440     }
 441
 442     if (certfile != NULL) {
 443         if (!load_certs(certfile, &other, FORMAT_PEM, NULL,
 444                         "certificate file")) {
 445             ERR_print_errors(bio_err);
 446             goto end;
 447         }
 448     }
 449
 450     if (recipfile != NULL && (operation == SMIME_DECRYPT)) {
 451         if ((recip = load_cert(recipfile, FORMAT_UNDEF,
 452                                "recipient certificate file")) == NULL) {
 453             ERR_print_errors(bio_err);
 454             goto end;
 455         }
 456     }
 457
 458     if (operation == SMIME_DECRYPT) {
 459         if (keyfile == NULL)
 460             keyfile = recipfile;
 461     } else if (operation == SMIME_SIGN) {
 462         if (keyfile == NULL)
 463             keyfile = signerfile;
 464     } else {
 465         keyfile = NULL;
 466     }
 467
 468     if (keyfile != NULL) {
 469         key = load_key(keyfile, keyform, 0, passin, e, "signing key file");
 470         if (key == NULL)
 471             goto end;
 472     }
 473
 474     in = bio_open_default(infile, 'r', informat);
 475     if (in == NULL)
 476         goto end;
 477
 478     if (operation & SMIME_IP) {
 479         if (informat == FORMAT_SMIME) {
 480             p7 = SMIME_read_PKCS7(in, &indata);
 481         } else if (informat == FORMAT_PEM) {
 482             p7 = PEM_read_bio_PKCS7(in, NULL, NULL, NULL);
 483         } else if (informat == FORMAT_ASN1) {
 484             p7 = d2i_PKCS7_bio(in, NULL);
 485         } else {
 486             BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
 487             goto end;
 488         }
 489
 490         if (p7 == NULL) {
 491             BIO_printf(bio_err, "Error reading S/MIME message\n");
 492             goto end;
 493         }
 494         if (contfile != NULL) {
 495             BIO_free(indata);
 496             if ((indata = BIO_new_file(contfile, "rb")) == NULL) {
 497                 BIO_printf(bio_err, "Can't read content file %s\n", contfile);
 498                 goto end;
 499             }
 500         }
 501     }
 502
 503     out = bio_open_default(outfile, 'w', outformat);
 504     if (out == NULL)
 505         goto end;
 506
 507     if (operation == SMIME_VERIFY) {
 508         if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
 509                                   CAstore, noCAstore)) == NULL)
 510             goto end;
 511         X509_STORE_set_verify_cb(store, smime_cb);
 512         if (vpmtouched)
 513             X509_STORE_set1_param(store, vpm);
 514     }
 515
 516     ret = 3;
 517
 518     if (operation == SMIME_ENCRYPT) {
 519         if (indef)
 520             flags |= PKCS7_STREAM;
 521         p7 = PKCS7_encrypt(encerts, in, cipher, flags);
 522     } else if (operation & SMIME_SIGNERS) {
 523         int i;
 524         /*
 525          * If detached data content we only enable streaming if S/MIME output
 526          * format.
 527          */
 528         if (operation == SMIME_SIGN) {
 529             if (flags & PKCS7_DETACHED) {
 530                 if (outformat == FORMAT_SMIME)
 531                     flags |= PKCS7_STREAM;
 532             } else if (indef) {
 533                 flags |= PKCS7_STREAM;
 534             }
 535             flags |= PKCS7_PARTIAL;
 536             p7 = PKCS7_sign(NULL, NULL, other, in, flags);
 537             if (p7 == NULL)
 538                 goto end;
 539             if (flags & PKCS7_NOCERTS) {
 540                 for (i = 0; i < sk_X509_num(other); i++) {
 541                     X509 *x = sk_X509_value(other, i);
 542                     PKCS7_add_certificate(p7, x);
 543                 }
 544             }
 545         } else {
 546             flags |= PKCS7_REUSE_DIGEST;
 547         }
 548         for (i = 0; i < sk_OPENSSL_STRING_num(sksigners); i++) {
 549             signerfile = sk_OPENSSL_STRING_value(sksigners, i);
 550             keyfile = sk_OPENSSL_STRING_value(skkeys, i);
 551             signer = load_cert(signerfile, FORMAT_UNDEF,
 552                                "signer certificate");
 553             if (signer == NULL)
 554                 goto end;
 555             key = load_key(keyfile, keyform, 0, passin, e, "signing key file");
 556             if (key == NULL)
 557                 goto end;
 558             if (!PKCS7_sign_add_signer(p7, signer, key, sign_md, flags))
 559                 goto end;
 560             X509_free(signer);
 561             signer = NULL;
 562             EVP_PKEY_free(key);
 563             key = NULL;
 564         }
 565         /* If not streaming or resigning finalize structure */
 566         if ((operation == SMIME_SIGN) && !(flags & PKCS7_STREAM)) {
 567             if (!PKCS7_final(p7, in, flags))
 568                 goto end;
 569         }
 570     }
 571
 572     if (p7 == NULL) {
 573         BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
 574         goto end;
 575     }
 576
 577     ret = 4;
 578     if (operation == SMIME_DECRYPT) {
 579         if (!PKCS7_decrypt(p7, key, recip, out, flags)) {
 580             BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
 581             goto end;
 582         }
 583     } else if (operation == SMIME_VERIFY) {
 584         STACK_OF(X509) *signers;
 585         if (PKCS7_verify(p7, other, store, indata, out, flags))
 586             BIO_printf(bio_err, "Verification successful\n");
 587         else {
 588             BIO_printf(bio_err, "Verification failure\n");
 589             goto end;
 590         }
 591         signers = PKCS7_get0_signers(p7, other, flags);
 592         if (!save_certs(signerfile, signers)) {
 593             BIO_printf(bio_err, "Error writing signers to %s\n", signerfile);
 594             ret = 5;
 595             goto end;
 596         }
 597         sk_X509_free(signers);
 598     } else if (operation == SMIME_PK7OUT) {
 599         PEM_write_bio_PKCS7(out, p7);
 600     } else {
 601         if (to)
 602             BIO_printf(out, "To: %s%s", to, mime_eol);
 603         if (from)
 604             BIO_printf(out, "From: %s%s", from, mime_eol);
 605         if (subject)
 606             BIO_printf(out, "Subject: %s%s", subject, mime_eol);
 607         if (outformat == FORMAT_SMIME) {
 608             if (operation == SMIME_RESIGN)
 609                 rv = SMIME_write_PKCS7(out, p7, indata, flags);
 610             else
 611                 rv = SMIME_write_PKCS7(out, p7, in, flags);
 612         } else if (outformat == FORMAT_PEM) {
 613             rv = PEM_write_bio_PKCS7_stream(out, p7, in, flags);
 614         } else if (outformat == FORMAT_ASN1) {
 615             rv = i2d_PKCS7_bio_stream(out, p7, in, flags);
 616         } else {
 617             BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
 618             goto end;
 619         }
 620         if (rv == 0) {
 621             BIO_printf(bio_err, "Error writing output\n");
 622             ret = 3;
 623             goto end;
 624         }
 625     }
 626     ret = 0;
 627  end:
 628     if (ret)
 629         ERR_print_errors(bio_err);
 630     sk_X509_pop_free(encerts, X509_free);
 631     sk_X509_pop_free(other, X509_free);
 632     X509_VERIFY_PARAM_free(vpm);
 633     sk_OPENSSL_STRING_free(sksigners);
 634     sk_OPENSSL_STRING_free(skkeys);
 635     X509_STORE_free(store);
 636     X509_free(cert);
 637     X509_free(recip);
 638     X509_free(signer);
 639     EVP_PKEY_free(key);
 640     PKCS7_free(p7);
 641     release_engine(e);
 642     BIO_free(in);
 643     BIO_free(indata);
 644     BIO_free_all(out);
 645     OPENSSL_free(passin);
 646     return ret;
 647 }
 648
 649 static int save_certs(char *signerfile, STACK_OF(X509) *signers)
 650 {
 651     int i;
 652     BIO *tmp;
 653
 654     if (signerfile == NULL)
 655         return 1;
 656     tmp = BIO_new_file(signerfile, "w");
 657     if (tmp == NULL)
 658         return 0;
 659     for (i = 0; i < sk_X509_num(signers); i++)
 660         PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
 661     BIO_free(tmp);
 662     return 1;
 663 }
 664
 665 /* Minimal callback just to output policy info (if any) */
 666
 667 static int smime_cb(int ok, X509_STORE_CTX *ctx)
 668 {
 669     int error;
 670
 671     error = X509_STORE_CTX_get_error(ctx);
 672
 673     if ((error != X509_V_ERR_NO_EXPLICIT_POLICY)
 674         && ((error != X509_V_OK) || (ok != 2)))
 675         return ok;
 676
 677     policies_print(ctx);
 678
 679     return ok;
 680 }