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, OPT_CONFIG,
  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     OPT_CONFIG_OPTION,
  74
  75     OPT_SECTION("Action"),
  76     {"encrypt", OPT_ENCRYPT, '-', "Encrypt message"},
  77     {"decrypt", OPT_DECRYPT, '-', "Decrypt encrypted message"},
  78     {"sign", OPT_SIGN, '-', "Sign message"},
  79     {"resign", OPT_RESIGN, '-', "Resign a signed message"},
  80     {"verify", OPT_VERIFY, '-', "Verify signed message"},
  81
  82     OPT_SECTION("Signing/Encryption"),
  83     {"passin", OPT_PASSIN, 's', "Input file pass phrase source"},
  84     {"md", OPT_MD, 's', "Digest algorithm to use when signing or resigning"},
  85     {"", OPT_CIPHER, '-', "Any supported cipher"},
  86     {"pk7out", OPT_PK7OUT, '-', "Output PKCS#7 structure"},
  87     {"nointern", OPT_NOINTERN, '-',
  88      "Don't search certificates in message for signer"},
  89     {"nodetach", OPT_NODETACH, '-', "Use opaque signing"},
  90     {"noattr", OPT_NOATTR, '-', "Don't include any signed attributes"},
  91     {"binary", OPT_BINARY, '-', "Don't translate message to text"},
  92     {"signer", OPT_SIGNER, 's', "Signer certificate file"},
  93     {"content", OPT_CONTENT, '<',
  94      "Supply or override content for detached signature"},
  95     {"nocerts", OPT_NOCERTS, '-',
  96      "Don't include signers certificate when signing"},
  97
  98     OPT_SECTION("Verification/Decryption"),
  99     {"nosigs", OPT_NOSIGS, '-', "Don't verify message signature"},
 100     {"noverify", OPT_NOVERIFY, '-', "Don't verify signers certificate"},
 101
 102     {"certfile", OPT_CERTFILE, '<', "Other certificates file"},
 103     {"recip", OPT_RECIP, '<', "Recipient certificate file for decryption"},
 104
 105     OPT_SECTION("Email"),
 106     {"to", OPT_TO, 's', "To address"},
 107     {"from", OPT_FROM, 's', "From address"},
 108     {"subject", OPT_SUBJECT, 's', "Subject"},
 109     {"text", OPT_TEXT, '-', "Include or delete text MIME headers"},
 110     {"nosmimecap", OPT_NOSMIMECAP, '-', "Omit the SMIMECapabilities attribute"},
 111
 112     OPT_SECTION("Certificate chain"),
 113     {"CApath", OPT_CAPATH, '/', "Trusted certificates directory"},
 114     {"CAfile", OPT_CAFILE, '<', "Trusted certificates file"},
 115     {"CAstore", OPT_CASTORE, ':', "Trusted certificates store URI"},
 116     {"no-CAfile", OPT_NOCAFILE, '-',
 117      "Do not load the default certificates file"},
 118     {"no-CApath", OPT_NOCAPATH, '-',
 119      "Do not load certificates from the default certificates directory"},
 120     {"no-CAstore", OPT_NOCASTORE, '-',
 121      "Do not load certificates from the default certificates store"},
 122     {"nochain", OPT_NOCHAIN, '-',
 123      "set PKCS7_NOCHAIN so certificates contained in the message are not used as untrusted CAs" },
 124     {"crlfeol", OPT_CRLFEOL, '-', "Use CRLF as EOL termination instead of CR only"},
 125
 126     OPT_R_OPTIONS,
 127     OPT_V_OPTIONS,
 128     OPT_PROV_OPTIONS,
 129
 130     OPT_PARAMETERS(),
 131     {"cert", 0, 0, "Recipient certs, used when encrypting"},
 132     {NULL}
 133 };
 134
 135 int smime_main(int argc, char **argv)
 136 {
 137     CONF *conf = NULL;
 138     BIO *in = NULL, *out = NULL, *indata = NULL;
 139     EVP_PKEY *key = NULL;
 140     PKCS7 *p7 = NULL;
 141     STACK_OF(OPENSSL_STRING) *sksigners = NULL, *skkeys = NULL;
 142     STACK_OF(X509) *encerts = NULL, *other = NULL;
 143     X509 *cert = NULL, *recip = NULL, *signer = NULL;
 144     X509_STORE *store = NULL;
 145     X509_VERIFY_PARAM *vpm = NULL;
 146     const EVP_CIPHER *cipher = NULL;
 147     const EVP_MD *sign_md = NULL;
 148     const char *CAfile = NULL, *CApath = NULL, *CAstore = NULL, *prog = NULL;
 149     char *certfile = NULL, *keyfile = NULL, *contfile = NULL;
 150     char *infile = NULL, *outfile = NULL, *signerfile = NULL, *recipfile = NULL;
 151     char *passinarg = NULL, *passin = NULL, *to = NULL, *from = NULL, *subject = NULL;
 152     OPTION_CHOICE o;
 153     int noCApath = 0, noCAfile = 0, noCAstore = 0;
 154     int flags = PKCS7_DETACHED, operation = 0, ret = 0, indef = 0;
 155     int informat = FORMAT_SMIME, outformat = FORMAT_SMIME, keyform =
 156         FORMAT_PEM;
 157     int vpmtouched = 0, rv = 0;
 158     ENGINE *e = NULL;
 159     const char *mime_eol = "\n";
 160     OPENSSL_CTX *libctx = app_get0_libctx();
 161     const char *propq = app_get0_propq();
 162
 163     if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
 164         return 1;
 165
 166     prog = opt_init(argc, argv, smime_options);
 167     while ((o = opt_next()) != OPT_EOF) {
 168         switch (o) {
 169         case OPT_EOF:
 170         case OPT_ERR:
 171  opthelp:
 172             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
 173             goto end;
 174         case OPT_HELP:
 175             opt_help(smime_options);
 176             ret = 0;
 177             goto end;
 178         case OPT_INFORM:
 179             if (!opt_format(opt_arg(), OPT_FMT_PDS, &informat))
 180                 goto opthelp;
 181             break;
 182         case OPT_IN:
 183             infile = opt_arg();
 184             break;
 185         case OPT_OUTFORM:
 186             if (!opt_format(opt_arg(), OPT_FMT_PDS, &outformat))
 187                 goto opthelp;
 188             break;
 189         case OPT_OUT:
 190             outfile = opt_arg();
 191             break;
 192         case OPT_ENCRYPT:
 193             operation = SMIME_ENCRYPT;
 194             break;
 195         case OPT_DECRYPT:
 196             operation = SMIME_DECRYPT;
 197             break;
 198         case OPT_SIGN:
 199             operation = SMIME_SIGN;
 200             break;
 201         case OPT_RESIGN:
 202             operation = SMIME_RESIGN;
 203             break;
 204         case OPT_VERIFY:
 205             operation = SMIME_VERIFY;
 206             break;
 207         case OPT_PK7OUT:
 208             operation = SMIME_PK7OUT;
 209             break;
 210         case OPT_TEXT:
 211             flags |= PKCS7_TEXT;
 212             break;
 213         case OPT_NOINTERN:
 214             flags |= PKCS7_NOINTERN;
 215             break;
 216         case OPT_NOVERIFY:
 217             flags |= PKCS7_NOVERIFY;
 218             break;
 219         case OPT_NOCHAIN:
 220             flags |= PKCS7_NOCHAIN;
 221             break;
 222         case OPT_NOCERTS:
 223             flags |= PKCS7_NOCERTS;
 224             break;
 225         case OPT_NOATTR:
 226             flags |= PKCS7_NOATTR;
 227             break;
 228         case OPT_NODETACH:
 229             flags &= ~PKCS7_DETACHED;
 230             break;
 231         case OPT_NOSMIMECAP:
 232             flags |= PKCS7_NOSMIMECAP;
 233             break;
 234         case OPT_BINARY:
 235             flags |= PKCS7_BINARY;
 236             break;
 237         case OPT_NOSIGS:
 238             flags |= PKCS7_NOSIGS;
 239             break;
 240         case OPT_STREAM:
 241         case OPT_INDEF:
 242             indef = 1;
 243             break;
 244         case OPT_NOINDEF:
 245             indef = 0;
 246             break;
 247         case OPT_CRLFEOL:
 248             flags |= PKCS7_CRLFEOL;
 249             mime_eol = "\r\n";
 250             break;
 251         case OPT_R_CASES:
 252             if (!opt_rand(o))
 253                 goto end;
 254             break;
 255         case OPT_PROV_CASES:
 256             if (!opt_provider(o))
 257                 goto end;
 258             break;
 259         case OPT_CONFIG:
 260             conf = app_load_config_modules(opt_arg());
 261             if (conf == NULL)
 262                 goto end;
 263             break;
 264         case OPT_ENGINE:
 265             e = setup_engine(opt_arg(), 0);
 266             break;
 267         case OPT_PASSIN:
 268             passinarg = opt_arg();
 269             break;
 270         case OPT_TO:
 271             to = opt_arg();
 272             break;
 273         case OPT_FROM:
 274             from = opt_arg();
 275             break;
 276         case OPT_SUBJECT:
 277             subject = opt_arg();
 278             break;
 279         case OPT_SIGNER:
 280             /* If previous -signer argument add signer to list */
 281             if (signerfile != NULL) {
 282                 if (sksigners == NULL
 283                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 284                     goto end;
 285                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 286                 if (keyfile == NULL)
 287                     keyfile = signerfile;
 288                 if (skkeys == NULL
 289                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 290                     goto end;
 291                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 292                 keyfile = NULL;
 293             }
 294             signerfile = opt_arg();
 295             break;
 296         case OPT_RECIP:
 297             recipfile = opt_arg();
 298             break;
 299         case OPT_MD:
 300             if (!opt_md(opt_arg(), &sign_md))
 301                 goto opthelp;
 302             break;
 303         case OPT_CIPHER:
 304             if (!opt_cipher(opt_unknown(), &cipher))
 305                 goto opthelp;
 306             break;
 307         case OPT_INKEY:
 308             /* If previous -inkey argument add signer to list */
 309             if (keyfile != NULL) {
 310                 if (signerfile == NULL) {
 311                     BIO_printf(bio_err,
 312                                "%s: Must have -signer before -inkey\n", prog);
 313                     goto opthelp;
 314                 }
 315                 if (sksigners == NULL
 316                     && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 317                     goto end;
 318                 sk_OPENSSL_STRING_push(sksigners, signerfile);
 319                 signerfile = NULL;
 320                 if (skkeys == NULL
 321                     && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 322                     goto end;
 323                 sk_OPENSSL_STRING_push(skkeys, keyfile);
 324             }
 325             keyfile = opt_arg();
 326             break;
 327         case OPT_KEYFORM:
 328             if (!opt_format(opt_arg(), OPT_FMT_ANY, &keyform))
 329                 goto opthelp;
 330             break;
 331         case OPT_CERTFILE:
 332             certfile = opt_arg();
 333             break;
 334         case OPT_CAFILE:
 335             CAfile = opt_arg();
 336             break;
 337         case OPT_CAPATH:
 338             CApath = opt_arg();
 339             break;
 340         case OPT_CASTORE:
 341             CAstore = opt_arg();
 342             break;
 343         case OPT_NOCAFILE:
 344             noCAfile = 1;
 345             break;
 346         case OPT_NOCAPATH:
 347             noCApath = 1;
 348             break;
 349         case OPT_NOCASTORE:
 350             noCAstore = 1;
 351             break;
 352         case OPT_CONTENT:
 353             contfile = opt_arg();
 354             break;
 355         case OPT_V_CASES:
 356             if (!opt_verify(o, vpm))
 357                 goto opthelp;
 358             vpmtouched++;
 359             break;
 360         }
 361     }
 362     argc = opt_num_rest();
 363     argv = opt_rest();
 364
 365     if (!(operation & SMIME_SIGNERS) && (skkeys != NULL || sksigners != NULL)) {
 366         BIO_puts(bio_err, "Multiple signers or keys not allowed\n");
 367         goto opthelp;
 368     }
 369
 370     if (operation & SMIME_SIGNERS) {
 371         /* Check to see if any final signer needs to be appended */
 372         if (keyfile && !signerfile) {
 373             BIO_puts(bio_err, "Illegal -inkey without -signer\n");
 374             goto opthelp;
 375         }
 376         if (signerfile != NULL) {
 377             if (sksigners == NULL
 378                 && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
 379                 goto end;
 380             sk_OPENSSL_STRING_push(sksigners, signerfile);
 381             if (!skkeys && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
 382                 goto end;
 383             if (!keyfile)
 384                 keyfile = signerfile;
 385             sk_OPENSSL_STRING_push(skkeys, keyfile);
 386         }
 387         if (sksigners == NULL) {
 388             BIO_printf(bio_err, "No signer certificate specified\n");
 389             goto opthelp;
 390         }
 391         signerfile = NULL;
 392         keyfile = NULL;
 393     } else if (operation == SMIME_DECRYPT) {
 394         if (recipfile == NULL && keyfile == NULL) {
 395             BIO_printf(bio_err,
 396                        "No recipient certificate or key specified\n");
 397             goto opthelp;
 398         }
 399     } else if (operation == SMIME_ENCRYPT) {
 400         if (argc == 0) {
 401             BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
 402             goto opthelp;
 403         }
 404     } else if (!operation) {
 405         goto opthelp;
 406     }
 407
 408     if (!app_passwd(passinarg, NULL, &passin, NULL)) {
 409         BIO_printf(bio_err, "Error getting password\n");
 410         goto end;
 411     }
 412
 413     ret = 2;
 414
 415     if (!(operation & SMIME_SIGNERS))
 416         flags &= ~PKCS7_DETACHED;
 417
 418     if (!(operation & SMIME_OP)) {
 419         if (flags & PKCS7_BINARY)
 420             outformat = FORMAT_BINARY;
 421     }
 422
 423     if (!(operation & SMIME_IP)) {
 424         if (flags & PKCS7_BINARY)
 425             informat = FORMAT_BINARY;
 426     }
 427
 428     if (operation == SMIME_ENCRYPT) {
 429         if (cipher == NULL) {
 430 #ifndef OPENSSL_NO_DES
 431             cipher = EVP_des_ede3_cbc();
 432 #else
 433             BIO_printf(bio_err, "No cipher selected\n");
 434             goto end;
 435 #endif
 436         }
 437         encerts = sk_X509_new_null();
 438         if (encerts == NULL)
 439             goto end;
 440         while (*argv != NULL) {
 441             cert = load_cert(*argv, FORMAT_UNDEF,
 442                              "recipient certificate file");
 443             if (cert == NULL)
 444                 goto end;
 445             sk_X509_push(encerts, cert);
 446             cert = NULL;
 447             argv++;
 448         }
 449     }
 450
 451     if (certfile != NULL) {
 452         if (!load_certs(certfile, &other, NULL, "certificates")) {
 453             ERR_print_errors(bio_err);
 454             goto end;
 455         }
 456     }
 457
 458     if (recipfile != NULL && (operation == SMIME_DECRYPT)) {
 459         if ((recip = load_cert(recipfile, FORMAT_UNDEF,
 460                                "recipient certificate file")) == NULL) {
 461             ERR_print_errors(bio_err);
 462             goto end;
 463         }
 464     }
 465
 466     if (operation == SMIME_DECRYPT) {
 467         if (keyfile == NULL)
 468             keyfile = recipfile;
 469     } else if (operation == SMIME_SIGN) {
 470         if (keyfile == NULL)
 471             keyfile = signerfile;
 472     } else {
 473         keyfile = NULL;
 474     }
 475
 476     if (keyfile != NULL) {
 477         key = load_key(keyfile, keyform, 0, passin, e, "signing key file");
 478         if (key == NULL)
 479             goto end;
 480
 481         /*
 482          * TODO: Remove this when CMS has full support for provider-native
 483          * EVP_PKEYs
 484          */
 485         if (EVP_PKEY_get0(key) == NULL)
 486             goto end;
 487
 488     }
 489
 490     in = bio_open_default(infile, 'r', informat);
 491     if (in == NULL)
 492         goto end;
 493
 494     if (operation & SMIME_IP) {
 495         PKCS7 *p7_in = NULL;
 496
 497         p7 = PKCS7_new_with_libctx(libctx, propq);
 498         if (p7 == NULL) {
 499             BIO_printf(bio_err, "Error allocating PKCS7 object\n");
 500             goto end;
 501         }
 502         if (informat == FORMAT_SMIME) {
 503             p7_in = SMIME_read_PKCS7_ex(in, &indata, &p7);
 504         } else if (informat == FORMAT_PEM) {
 505             p7_in = PEM_read_bio_PKCS7(in, &p7, NULL, NULL);
 506         } else if (informat == FORMAT_ASN1) {
 507             p7_in = d2i_PKCS7_bio(in, &p7);
 508         } else {
 509             BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
 510             goto end;
 511         }
 512
 513         if (p7_in == NULL) {
 514             BIO_printf(bio_err, "Error reading S/MIME message\n");
 515             goto end;
 516         }
 517         if (contfile != NULL) {
 518             BIO_free(indata);
 519             if ((indata = BIO_new_file(contfile, "rb")) == NULL) {
 520                 BIO_printf(bio_err, "Can't read content file %s\n", contfile);
 521                 goto end;
 522             }
 523         }
 524     }
 525
 526     out = bio_open_default(outfile, 'w', outformat);
 527     if (out == NULL)
 528         goto end;
 529
 530     if (operation == SMIME_VERIFY) {
 531         if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
 532                                   CAstore, noCAstore)) == NULL)
 533             goto end;
 534         X509_STORE_set_verify_cb(store, smime_cb);
 535         if (vpmtouched)
 536             X509_STORE_set1_param(store, vpm);
 537     }
 538
 539     ret = 3;
 540
 541     if (operation == SMIME_ENCRYPT) {
 542         if (indef)
 543             flags |= PKCS7_STREAM;
 544         p7 = PKCS7_encrypt_with_libctx(encerts, in, cipher, flags, libctx, propq);
 545     } else if (operation & SMIME_SIGNERS) {
 546         int i;
 547         /*
 548          * If detached data content we only enable streaming if S/MIME output
 549          * format.
 550          */
 551         if (operation == SMIME_SIGN) {
 552             if (flags & PKCS7_DETACHED) {
 553                 if (outformat == FORMAT_SMIME)
 554                     flags |= PKCS7_STREAM;
 555             } else if (indef) {
 556                 flags |= PKCS7_STREAM;
 557             }
 558             flags |= PKCS7_PARTIAL;
 559             p7 = PKCS7_sign_with_libctx(NULL, NULL, other, in, flags, libctx,
 560                                         propq);
 561             if (p7 == NULL)
 562                 goto end;
 563             if (flags & PKCS7_NOCERTS) {
 564                 for (i = 0; i < sk_X509_num(other); i++) {
 565                     X509 *x = sk_X509_value(other, i);
 566                     PKCS7_add_certificate(p7, x);
 567                 }
 568             }
 569         } else {
 570             flags |= PKCS7_REUSE_DIGEST;
 571         }
 572         for (i = 0; i < sk_OPENSSL_STRING_num(sksigners); i++) {
 573             signerfile = sk_OPENSSL_STRING_value(sksigners, i);
 574             keyfile = sk_OPENSSL_STRING_value(skkeys, i);
 575             signer = load_cert(signerfile, FORMAT_UNDEF,
 576                                "signer certificate");
 577             if (signer == NULL)
 578                 goto end;
 579             key = load_key(keyfile, keyform, 0, passin, e, "signing key file");
 580             if (key == NULL)
 581                 goto end;
 582
 583             /*
 584              * TODO: Remove this when CMS has full support for provider-native
 585              * EVP_PKEYs
 586              */
 587             if (EVP_PKEY_get0(key) == NULL)
 588                 goto end;
 589
 590             if (!PKCS7_sign_add_signer(p7, signer, key, sign_md, flags))
 591                 goto end;
 592             X509_free(signer);
 593             signer = NULL;
 594             EVP_PKEY_free(key);
 595             key = NULL;
 596         }
 597         /* If not streaming or resigning finalize structure */
 598         if ((operation == SMIME_SIGN) && !(flags & PKCS7_STREAM)) {
 599             if (!PKCS7_final(p7, in, flags))
 600                 goto end;
 601         }
 602     }
 603
 604     if (p7 == NULL) {
 605         BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
 606         goto end;
 607     }
 608
 609     ret = 4;
 610     if (operation == SMIME_DECRYPT) {
 611         if (!PKCS7_decrypt(p7, key, recip, out, flags)) {
 612             BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
 613             goto end;
 614         }
 615     } else if (operation == SMIME_VERIFY) {
 616         STACK_OF(X509) *signers;
 617         if (PKCS7_verify(p7, other, store, indata, out, flags))
 618             BIO_printf(bio_err, "Verification successful\n");
 619         else {
 620             BIO_printf(bio_err, "Verification failure\n");
 621             goto end;
 622         }
 623         signers = PKCS7_get0_signers(p7, other, flags);
 624         if (!save_certs(signerfile, signers)) {
 625             BIO_printf(bio_err, "Error writing signers to %s\n", signerfile);
 626             ret = 5;
 627             goto end;
 628         }
 629         sk_X509_free(signers);
 630     } else if (operation == SMIME_PK7OUT) {
 631         PEM_write_bio_PKCS7(out, p7);
 632     } else {
 633         if (to)
 634             BIO_printf(out, "To: %s%s", to, mime_eol);
 635         if (from)
 636             BIO_printf(out, "From: %s%s", from, mime_eol);
 637         if (subject)
 638             BIO_printf(out, "Subject: %s%s", subject, mime_eol);
 639         if (outformat == FORMAT_SMIME) {
 640             if (operation == SMIME_RESIGN)
 641                 rv = SMIME_write_PKCS7(out, p7, indata, flags);
 642             else
 643                 rv = SMIME_write_PKCS7(out, p7, in, flags);
 644         } else if (outformat == FORMAT_PEM) {
 645             rv = PEM_write_bio_PKCS7_stream(out, p7, in, flags);
 646         } else if (outformat == FORMAT_ASN1) {
 647             rv = i2d_PKCS7_bio_stream(out, p7, in, flags);
 648         } else {
 649             BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
 650             goto end;
 651         }
 652         if (rv == 0) {
 653             BIO_printf(bio_err, "Error writing output\n");
 654             ret = 3;
 655             goto end;
 656         }
 657     }
 658     ret = 0;
 659  end:
 660     if (ret)
 661         ERR_print_errors(bio_err);
 662     sk_X509_pop_free(encerts, X509_free);
 663     sk_X509_pop_free(other, X509_free);
 664     X509_VERIFY_PARAM_free(vpm);
 665     sk_OPENSSL_STRING_free(sksigners);
 666     sk_OPENSSL_STRING_free(skkeys);
 667     X509_STORE_free(store);
 668     X509_free(cert);
 669     X509_free(recip);
 670     X509_free(signer);
 671     EVP_PKEY_free(key);
 672     PKCS7_free(p7);
 673     release_engine(e);
 674     BIO_free(in);
 675     BIO_free(indata);
 676     BIO_free_all(out);
 677     OPENSSL_free(passin);
 678     NCONF_free(conf);
 679     return ret;
 680 }
 681
 682 static int save_certs(char *signerfile, STACK_OF(X509) *signers)
 683 {
 684     int i;
 685     BIO *tmp;
 686
 687     if (signerfile == NULL)
 688         return 1;
 689     tmp = BIO_new_file(signerfile, "w");
 690     if (tmp == NULL)
 691         return 0;
 692     for (i = 0; i < sk_X509_num(signers); i++)
 693         PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
 694     BIO_free(tmp);
 695     return 1;
 696 }
 697
 698 /* Minimal callback just to output policy info (if any) */
 699
 700 static int smime_cb(int ok, X509_STORE_CTX *ctx)
 701 {
 702     int error;
 703
 704     error = X509_STORE_CTX_get_error(ctx);
 705
 706     if ((error != X509_V_ERR_NO_EXPLICIT_POLICY)
 707         && ((error != X509_V_OK) || (ok != 2)))
 708         return ok;
 709
 710     policies_print(ctx);
 711
 712     return ok;
 713 }