apps/smime.c

   1 /*
   2  * Copyright 1999-2021 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 /* 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, OPT_PROV_ENUM, OPT_CONFIG,
  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 (ENGINE, other values ignored)"},
  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     OPT_CONFIG_OPTION,
  71
  72     OPT_SECTION("Action"),
  73     {"encrypt", OPT_ENCRYPT, '-', "Encrypt message"},
  74     {"decrypt", OPT_DECRYPT, '-', "Decrypt encrypted message"},
  75     {"sign", OPT_SIGN, '-', "Sign message"},
  76     {"resign", OPT_RESIGN, '-', "Resign a signed message"},
  77     {"verify", OPT_VERIFY, '-', "Verify signed message"},
  78
  79     OPT_SECTION("Signing/Encryption"),
  80     {"passin", OPT_PASSIN, 's', "Input file pass phrase source"},
  81     {"md", OPT_MD, 's', "Digest algorithm to use when signing or resigning"},
  82     {"", OPT_CIPHER, '-', "Any supported cipher"},
  83     {"pk7out", OPT_PK7OUT, '-', "Output PKCS#7 structure"},
  84     {"nointern", OPT_NOINTERN, '-',
  85      "Don't search certificates in message for signer"},
  86     {"nodetach", OPT_NODETACH, '-', "Use opaque signing"},
  87     {"noattr", OPT_NOATTR, '-', "Don't include any signed attributes"},
  88     {"binary", OPT_BINARY, '-', "Don't translate message to text"},
  89     {"signer", OPT_SIGNER, 's', "Signer certificate file"},
  90     {"content", OPT_CONTENT, '<',
  91      "Supply or override content for detached signature"},
  92     {"nocerts", OPT_NOCERTS, '-',
  93      "Don't include signers certificate when signing"},
  94
  95     OPT_SECTION("Verification/Decryption"),
  96     {"nosigs", OPT_NOSIGS, '-', "Don't verify message signature"},
  97     {"noverify", OPT_NOVERIFY, '-', "Don't verify signers certificate"},
  98
  99     {"certfile", OPT_CERTFILE, '<', "Other certificates file"},
 100     {"recip", OPT_RECIP, '<', "Recipient certificate file for decryption"},
 101
 102     OPT_SECTION("Email"),
 103     {"to", OPT_TO, 's', "To address"},
 104     {"from", OPT_FROM, 's', "From address"},
 105     {"subject", OPT_SUBJECT, 's', "Subject"},
 106     {"text", OPT_TEXT, '-', "Include or delete text MIME headers"},
 107     {"nosmimecap", OPT_NOSMIMECAP, '-', "Omit the SMIMECapabilities attribute"},
 108
 109     OPT_SECTION("Certificate chain"),
 110     {"CApath", OPT_CAPATH, '/', "Trusted certificates directory"},
 111     {"CAfile", OPT_CAFILE, '<', "Trusted certificates file"},
 112     {"CAstore", OPT_CASTORE, ':', "Trusted certificates store URI"},
 113     {"no-CAfile", OPT_NOCAFILE, '-',
 114      "Do not load the default certificates file"},
 115     {"no-CApath", OPT_NOCAPATH, '-',
 116      "Do not load certificates from the default certificates directory"},
 117     {"no-CAstore", OPT_NOCASTORE, '-',
 118      "Do not load certificates from the default certificates store"},
 119     {"nochain", OPT_NOCHAIN, '-',
 120      "set PKCS7_NOCHAIN so certificates contained in the message are not used as untrusted CAs" },
 121     {"crlfeol", OPT_CRLFEOL, '-', "Use CRLF as EOL termination instead of CR only"},
 122
 123     OPT_R_OPTIONS,
 124     OPT_V_OPTIONS,
 125     OPT_PROV_OPTIONS,
 126
 127     OPT_PARAMETERS(),
 128     {"cert", 0, 0, "Recipient certs, used when encrypting"},
 129     {NULL}
 130 };
 131
 132 int smime_main(int argc, char **argv)
 133 {
 134     CONF *conf = NULL;
 135     BIO *in = NULL, *out = NULL, *indata = NULL;
 136     EVP_PKEY *key = NULL;
 137     PKCS7 *p7 = NULL;
 138     STACK_OF(OPENSSL_STRING) *sksigners = NULL, *skkeys = NULL;
 139     STACK_OF(X509) *encerts = NULL, *other = NULL;
 140     X509 *cert = NULL, *recip = NULL, *signer = NULL;
 141     X509_STORE *store = NULL;
 142     X509_VERIFY_PARAM *vpm = NULL;
 143     const EVP_CIPHER *cipher = NULL;
 144     const EVP_MD *sign_md = NULL;
 145     const char *CAfile = NULL, *CApath = NULL, *CAstore = NULL, *prog = NULL;
 146     char *certfile = NULL, *keyfile = NULL, *contfile = NULL;
 147     char *infile = NULL, *outfile = NULL, *signerfile = NULL, *recipfile = NULL;
 148     char *passinarg = NULL, *passin = NULL, *to = NULL, *from = NULL, *subject = NULL;
 149     OPTION_CHOICE o;
 150     int noCApath = 0, noCAfile = 0, noCAstore = 0;
 151     int flags = PKCS7_DETACHED, operation = 0, ret = 0, indef = 0;
 152     int informat = FORMAT_SMIME, outformat = FORMAT_SMIME, keyform =
 153         FORMAT_PEM;
 154     int vpmtouched = 0, rv = 0;
 155     ENGINE *e = NULL;
 156     const char *mime_eol = "\n";
 157     OSSL_LIB_CTX *libctx = app_get0_libctx();
 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_CONFIG:
 256             conf = app_load_config_modules(opt_arg());
 257             if (conf == NULL)
 258                 goto end;
 259             break;
 260         case OPT_ENGINE:
 261             e = setup_engine(opt_arg(), 0);
 262             break;
 263         case OPT_PASSIN:
 264             passinarg = opt_arg();
 265             break;
 266         case OPT_TO:
 267             to = opt_arg();
 268             break;
 269         case OPT_FROM:
 270             from = opt_arg();
 271             break;
 272         case OPT_SUBJECT:
 273             subject = opt_arg();
 274             break;
 275         case OPT_SIGNER:
 276             /* If previous -signer argument add signer to list */
 277             if (signerfile != NULL) {
 278                 if (sksigners == NULL
 279                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 280                     goto end;
 281                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 282                 if (keyfile == NULL)
 283                     keyfile = signerfile;
 284                 if (skkeys == NULL
 285                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 286                     goto end;
 287                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 288                 keyfile = NULL;
 289             }
 290             signerfile = opt_arg();
 291             break;
 292         case OPT_RECIP:
 293             recipfile = opt_arg();
 294             break;
 295         case OPT_MD:
 296             if (!opt_md(opt_arg(), &sign_md))
 297                 goto opthelp;
 298             break;
 299         case OPT_CIPHER:
 300             if (!opt_cipher(opt_unknown(), &cipher))
 301                 goto opthelp;
 302             break;
 303         case OPT_INKEY:
 304             /* If previous -inkey argument add signer to list */
 305             if (keyfile != NULL) {
 306                 if (signerfile == NULL) {
 307                     BIO_printf(bio_err,
 308                                "%s: Must have -signer before -inkey\n", prog);
 309                     goto opthelp;
 310                 }
 311                 if (sksigners == NULL
 312                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 313                     goto end;
 314                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 315                 signerfile = NULL;
 316                 if (skkeys == NULL
 317                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 318                     goto end;
 319                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 320             }
 321             keyfile = opt_arg();
 322             break;
 323         case OPT_KEYFORM:
 324             if (!opt_format(opt_arg(), OPT_FMT_ANY, &keyform))
 325                 goto opthelp;
 326             break;
 327         case OPT_CERTFILE:
 328             certfile = opt_arg();
 329             break;
 330         case OPT_CAFILE:
 331             CAfile = opt_arg();
 332             break;
 333         case OPT_CAPATH:
 334             CApath = opt_arg();
 335             break;
 336         case OPT_CASTORE:
 337             CAstore = opt_arg();
 338             break;
 339         case OPT_NOCAFILE:
 340             noCAfile = 1;
 341             break;
 342         case OPT_NOCAPATH:
 343             noCApath = 1;
 344             break;
 345         case OPT_NOCASTORE:
 346             noCAstore = 1;
 347             break;
 348         case OPT_CONTENT:
 349             contfile = opt_arg();
 350             break;
 351         case OPT_V_CASES:
 352             if (!opt_verify(o, vpm))
 353                 goto opthelp;
 354             vpmtouched++;
 355             break;
 356         }
 357     }
 358
 359     /* Extra arguments are files with recipient keys. */
 360     argc = opt_num_rest();
 361     argv = opt_rest();
 362
 363     app_RAND_load();
 364     if (!(operation & SMIME_SIGNERS) && (skkeys != NULL || sksigners != NULL)) {
 365         BIO_puts(bio_err, "Multiple signers or keys not allowed\n");
 366         goto opthelp;
 367     }
 368     if (!operation) {
 369         BIO_puts(bio_err,
 370                 "No operation (-encrypt|-sign|...) specified\n");
 371         goto opthelp;
 372     }
 373
 374     if (operation & SMIME_SIGNERS) {
 375         /* Check to see if any final signer needs to be appended */
 376         if (keyfile && !signerfile) {
 377             BIO_puts(bio_err, "Illegal -inkey without -signer\n");
 378             goto opthelp;
 379         }
 380         if (signerfile != NULL) {
 381             if (sksigners == NULL
 382                 && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 383                 goto end;
 384             sk_OPENSSL_STRING_push(sksigners, signerfile);
 385             if (!skkeys && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 386                 goto end;
 387             if (!keyfile)
 388                 keyfile = signerfile;
 389             sk_OPENSSL_STRING_push(skkeys, keyfile);
 390         }
 391         if (sksigners == NULL) {
 392             BIO_printf(bio_err, "No signer certificate specified\n");
 393             goto opthelp;
 394         }
 395         signerfile = NULL;
 396         keyfile = NULL;
 397     } else if (operation == SMIME_DECRYPT) {
 398         if (recipfile == NULL && keyfile == NULL) {
 399             BIO_printf(bio_err,
 400                        "No recipient certificate or key specified\n");
 401             goto opthelp;
 402         }
 403     } else if (operation == SMIME_ENCRYPT) {
 404         if (argc == 0) {
 405             BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
 406             goto opthelp;
 407         }
 408     }
 409
 410     if (!app_passwd(passinarg, NULL, &passin, NULL)) {
 411         BIO_printf(bio_err, "Error getting password\n");
 412         goto end;
 413     }
 414
 415     ret = 2;
 416
 417     if (!(operation & SMIME_SIGNERS))
 418         flags &= ~PKCS7_DETACHED;
 419
 420     if (!(operation & SMIME_OP)) {
 421         if (flags & PKCS7_BINARY)
 422             outformat = FORMAT_BINARY;
 423     }
 424
 425     if (!(operation & SMIME_IP)) {
 426         if (flags & PKCS7_BINARY)
 427             informat = FORMAT_BINARY;
 428     }
 429
 430     if (operation == SMIME_ENCRYPT) {
 431         if (cipher == NULL) {
 432 #ifndef OPENSSL_NO_DES
 433             cipher = EVP_des_ede3_cbc();
 434 #else
 435             BIO_printf(bio_err, "No cipher selected\n");
 436             goto end;
 437 #endif
 438         }
 439         encerts = sk_X509_new_null();
 440         if (encerts == NULL)
 441             goto end;
 442         while (*argv != NULL) {
 443             cert = load_cert(*argv, "recipient certificate file");
 444             if (cert == NULL)
 445                 goto end;
 446             sk_X509_push(encerts, cert);
 447             cert = NULL;
 448             argv++;
 449         }
 450     }
 451
 452     if (certfile != NULL) {
 453         if (!load_certs(certfile, &other, NULL, "certificates")) {
 454             ERR_print_errors(bio_err);
 455             goto end;
 456         }
 457     }
 458
 459     if (recipfile != NULL && (operation == SMIME_DECRYPT)) {
 460         if ((recip = load_cert(recipfile,
 461                                "recipient certificate file")) == NULL) {
 462             ERR_print_errors(bio_err);
 463             goto end;
 464         }
 465     }
 466
 467     if (operation == SMIME_DECRYPT) {
 468         if (keyfile == NULL)
 469             keyfile = recipfile;
 470     } else if (operation == SMIME_SIGN) {
 471         if (keyfile == NULL)
 472             keyfile = signerfile;
 473     } else {
 474         keyfile = NULL;
 475     }
 476
 477     if (keyfile != NULL) {
 478         key = load_key(keyfile, keyform, 0, passin, e, "signing key");
 479         if (key == NULL)
 480             goto end;
 481     }
 482
 483     in = bio_open_default(infile, 'r', informat);
 484     if (in == NULL)
 485         goto end;
 486
 487     if (operation & SMIME_IP) {
 488         PKCS7 *p7_in = NULL;
 489
 490         p7 = PKCS7_new_ex(libctx, app_get0_propq());
 491         if (p7 == NULL) {
 492             BIO_printf(bio_err, "Error allocating PKCS7 object\n");
 493             goto end;
 494         }
 495         if (informat == FORMAT_SMIME) {
 496             p7_in = SMIME_read_PKCS7_ex(in, &indata, &p7);
 497         } else if (informat == FORMAT_PEM) {
 498             p7_in = PEM_read_bio_PKCS7(in, &p7, NULL, NULL);
 499         } else if (informat == FORMAT_ASN1) {
 500             p7_in = d2i_PKCS7_bio(in, &p7);
 501         } else {
 502             BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
 503             goto end;
 504         }
 505
 506         if (p7_in == NULL) {
 507             BIO_printf(bio_err, "Error reading S/MIME message\n");
 508             goto end;
 509         }
 510         if (contfile != NULL) {
 511             BIO_free(indata);
 512             if ((indata = BIO_new_file(contfile, "rb")) == NULL) {
 513                 BIO_printf(bio_err, "Can't read content file %s\n", contfile);
 514                 goto end;
 515             }
 516         }
 517     }
 518
 519     out = bio_open_default(outfile, 'w', outformat);
 520     if (out == NULL)
 521         goto end;
 522
 523     if (operation == SMIME_VERIFY) {
 524         if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
 525                                   CAstore, noCAstore)) == NULL)
 526             goto end;
 527         X509_STORE_set_verify_cb(store, smime_cb);
 528         if (vpmtouched)
 529             X509_STORE_set1_param(store, vpm);
 530     }
 531
 532     ret = 3;
 533
 534     if (operation == SMIME_ENCRYPT) {
 535         if (indef)
 536             flags |= PKCS7_STREAM;
 537         p7 = PKCS7_encrypt_ex(encerts, in, cipher, flags, libctx, app_get0_propq());
 538     } else if (operation & SMIME_SIGNERS) {
 539         int i;
 540         /*
 541          * If detached data content we only enable streaming if S/MIME output
 542          * format.
 543          */
 544         if (operation == SMIME_SIGN) {
 545             if (flags & PKCS7_DETACHED) {
 546                 if (outformat == FORMAT_SMIME)
 547                     flags |= PKCS7_STREAM;
 548             } else if (indef) {
 549                 flags |= PKCS7_STREAM;
 550             }
 551             flags |= PKCS7_PARTIAL;
 552             p7 = PKCS7_sign_ex(NULL, NULL, other, in, flags, libctx, app_get0_propq());
 553             if (p7 == NULL)
 554                 goto end;
 555             if (flags & PKCS7_NOCERTS) {
 556                 for (i = 0; i < sk_X509_num(other); i++) {
 557                     X509 *x = sk_X509_value(other, i);
 558                     PKCS7_add_certificate(p7, x);
 559                 }
 560             }
 561         } else {
 562             flags |= PKCS7_REUSE_DIGEST;
 563         }
 564         for (i = 0; i < sk_OPENSSL_STRING_num(sksigners); i++) {
 565             signerfile = sk_OPENSSL_STRING_value(sksigners, i);
 566             keyfile = sk_OPENSSL_STRING_value(skkeys, i);
 567             signer = load_cert(signerfile, "signer certificate");
 568             if (signer == NULL)
 569                 goto end;
 570             key = load_key(keyfile, keyform, 0, passin, e, "signing key");
 571             if (key == NULL)
 572                 goto end;
 573
 574             if (!PKCS7_sign_add_signer(p7, signer, key, sign_md, flags))
 575                 goto end;
 576             X509_free(signer);
 577             signer = NULL;
 578             EVP_PKEY_free(key);
 579             key = NULL;
 580         }
 581         /* If not streaming or resigning finalize structure */
 582         if ((operation == SMIME_SIGN) && !(flags & PKCS7_STREAM)) {
 583             if (!PKCS7_final(p7, in, flags))
 584                 goto end;
 585         }
 586     }
 587
 588     if (p7 == NULL) {
 589         BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
 590         goto end;
 591     }
 592
 593     ret = 4;
 594     if (operation == SMIME_DECRYPT) {
 595         if (!PKCS7_decrypt(p7, key, recip, out, flags)) {
 596             BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
 597             goto end;
 598         }
 599     } else if (operation == SMIME_VERIFY) {
 600         STACK_OF(X509) *signers;
 601         if (PKCS7_verify(p7, other, store, indata, out, flags))
 602             BIO_printf(bio_err, "Verification successful\n");
 603         else {
 604             BIO_printf(bio_err, "Verification failure\n");
 605             goto end;
 606         }
 607         signers = PKCS7_get0_signers(p7, other, flags);
 608         if (!save_certs(signerfile, signers)) {
 609             BIO_printf(bio_err, "Error writing signers to %s\n", signerfile);
 610             ret = 5;
 611             goto end;
 612         }
 613         sk_X509_free(signers);
 614     } else if (operation == SMIME_PK7OUT) {
 615         PEM_write_bio_PKCS7(out, p7);
 616     } else {
 617         if (to)
 618             BIO_printf(out, "To: %s%s", to, mime_eol);
 619         if (from)
 620             BIO_printf(out, "From: %s%s", from, mime_eol);
 621         if (subject)
 622             BIO_printf(out, "Subject: %s%s", subject, mime_eol);
 623         if (outformat == FORMAT_SMIME) {
 624             if (operation == SMIME_RESIGN)
 625                 rv = SMIME_write_PKCS7(out, p7, indata, flags);
 626             else
 627                 rv = SMIME_write_PKCS7(out, p7, in, flags);
 628         } else if (outformat == FORMAT_PEM) {
 629             rv = PEM_write_bio_PKCS7_stream(out, p7, in, flags);
 630         } else if (outformat == FORMAT_ASN1) {
 631             rv = i2d_PKCS7_bio_stream(out, p7, in, flags);
 632         } else {
 633             BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
 634             goto end;
 635         }
 636         if (rv == 0) {
 637             BIO_printf(bio_err, "Error writing output\n");
 638             ret = 3;
 639             goto end;
 640         }
 641     }
 642     ret = 0;
 643  end:
 644     if (ret)
 645         ERR_print_errors(bio_err);
 646     sk_X509_pop_free(encerts, X509_free);
 647     sk_X509_pop_free(other, X509_free);
 648     X509_VERIFY_PARAM_free(vpm);
 649     sk_OPENSSL_STRING_free(sksigners);
 650     sk_OPENSSL_STRING_free(skkeys);
 651     X509_STORE_free(store);
 652     X509_free(cert);
 653     X509_free(recip);
 654     X509_free(signer);
 655     EVP_PKEY_free(key);
 656     PKCS7_free(p7);
 657     release_engine(e);
 658     BIO_free(in);
 659     BIO_free(indata);
 660     BIO_free_all(out);
 661     OPENSSL_free(passin);
 662     NCONF_free(conf);
 663     return ret;
 664 }
 665
 666 static int save_certs(char *signerfile, STACK_OF(X509) *signers)
 667 {
 668     int i;
 669     BIO *tmp;
 670
 671     if (signerfile == NULL)
 672         return 1;
 673     tmp = BIO_new_file(signerfile, "w");
 674     if (tmp == NULL)
 675         return 0;
 676     for (i = 0; i < sk_X509_num(signers); i++)
 677         PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
 678     BIO_free(tmp);
 679     return 1;
 680 }
 681
 682 /* Minimal callback just to output policy info (if any) */
 683
 684 static int smime_cb(int ok, X509_STORE_CTX *ctx)
 685 {
 686     int error;
 687
 688     error = X509_STORE_CTX_get_error(ctx);
 689
 690     if ((error != X509_V_ERR_NO_EXPLICIT_POLICY)
 691         && ((error != X509_V_OK) || (ok != 2)))
 692         return ok;
 693
 694     policies_print(ctx);
 695
 696     return ok;
 697 }