2 * Copyright 1999-2021 The OpenSSL Project Authors. All Rights Reserved.
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
10 /* S/MIME utility function */
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>
22 static int save_certs(char *signerfile, STACK_OF(X509) *signers);
23 static int smime_cb(int ok, X509_STORE_CTX *ctx);
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)
35 typedef enum OPTION_choice {
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,
47 OPT_IN, OPT_INFORM, OPT_OUT,
48 OPT_OUTFORM, OPT_CONTENT
51 const OPTIONS smime_options[] = {
52 {OPT_HELP_STR, 1, '-', "Usage: %s [options] [cert...]\n"},
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"},
67 {"stream", OPT_STREAM, '-', "Enable CMS streaming" },
68 {"indef", OPT_INDEF, '-', "Same as -stream" },
69 {"noindef", OPT_NOINDEF, '-', "Disable CMS streaming"},
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"},
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"},
95 OPT_SECTION("Verification/Decryption"),
96 {"nosigs", OPT_NOSIGS, '-', "Don't verify message signature"},
97 {"noverify", OPT_NOVERIFY, '-', "Don't verify signers certificate"},
99 {"certfile", OPT_CERTFILE, '<', "Other certificates file"},
100 {"recip", OPT_RECIP, '<', "Recipient certificate file for decryption"},
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"},
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"},
128 {"cert", 0, 0, "Recipient certs, used when encrypting"},
132 int smime_main(int argc, char **argv)
135 BIO *in = NULL, *out = NULL, *indata = NULL;
136 EVP_PKEY *key = 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 EVP_CIPHER *cipher = NULL;
144 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;
149 char *subject = NULL, *digestname = NULL, *ciphername = NULL;
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 =
155 int vpmtouched = 0, rv = 0;
157 const char *mime_eol = "\n";
158 OSSL_LIB_CTX *libctx = app_get0_libctx();
160 if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
163 opt_set_unknown_name("cipher");
164 prog = opt_init(argc, argv, smime_options);
165 while ((o = opt_next()) != OPT_EOF) {
170 BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
173 opt_help(smime_options);
177 if (!opt_format(opt_arg(), OPT_FMT_PDS, &informat))
184 if (!opt_format(opt_arg(), OPT_FMT_PDS, &outformat))
191 operation = SMIME_ENCRYPT;
194 operation = SMIME_DECRYPT;
197 operation = SMIME_SIGN;
200 operation = SMIME_RESIGN;
203 operation = SMIME_VERIFY;
206 operation = SMIME_PK7OUT;
212 flags |= PKCS7_NOINTERN;
215 flags |= PKCS7_NOVERIFY;
218 flags |= PKCS7_NOCHAIN;
221 flags |= PKCS7_NOCERTS;
224 flags |= PKCS7_NOATTR;
227 flags &= ~PKCS7_DETACHED;
230 flags |= PKCS7_NOSMIMECAP;
233 flags |= PKCS7_BINARY;
236 flags |= PKCS7_NOSIGS;
246 flags |= PKCS7_CRLFEOL;
254 if (!opt_provider(o))
258 conf = app_load_config_modules(opt_arg());
263 e = setup_engine(opt_arg(), 0);
266 passinarg = opt_arg();
278 /* If previous -signer argument add signer to list */
279 if (signerfile != NULL) {
280 if (sksigners == NULL
281 && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
283 sk_OPENSSL_STRING_push(sksigners, signerfile);
285 keyfile = signerfile;
287 && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
289 sk_OPENSSL_STRING_push(skkeys, keyfile);
292 signerfile = opt_arg();
295 recipfile = opt_arg();
298 digestname = opt_arg();
301 ciphername = opt_unknown();
304 /* If previous -inkey argument add signer to list */
305 if (keyfile != NULL) {
306 if (signerfile == NULL) {
308 "%s: Must have -signer before -inkey\n", prog);
311 if (sksigners == NULL
312 && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
314 sk_OPENSSL_STRING_push(sksigners, signerfile);
317 && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
319 sk_OPENSSL_STRING_push(skkeys, keyfile);
324 if (!opt_format(opt_arg(), OPT_FMT_ANY, &keyform))
328 certfile = opt_arg();
349 contfile = opt_arg();
352 if (!opt_verify(o, vpm))
359 /* Extra arguments are files with recipient keys. */
360 argc = opt_num_rest();
363 if (!app_RAND_load())
366 if (digestname != NULL) {
367 if (!opt_md(digestname, &sign_md))
370 if (!opt_cipher_any(ciphername, &cipher))
372 if (!(operation & SMIME_SIGNERS) && (skkeys != NULL || sksigners != NULL)) {
373 BIO_puts(bio_err, "Multiple signers or keys not allowed\n");
378 "No operation (-encrypt|-sign|...) specified\n");
382 if (operation & SMIME_SIGNERS) {
383 /* Check to see if any final signer needs to be appended */
384 if (keyfile && !signerfile) {
385 BIO_puts(bio_err, "Illegal -inkey without -signer\n");
388 if (signerfile != NULL) {
389 if (sksigners == NULL
390 && (sksigners = sk_OPENSSL_STRING_new_null()) == NULL)
392 sk_OPENSSL_STRING_push(sksigners, signerfile);
393 if (!skkeys && (skkeys = sk_OPENSSL_STRING_new_null()) == NULL)
396 keyfile = signerfile;
397 sk_OPENSSL_STRING_push(skkeys, keyfile);
399 if (sksigners == NULL) {
400 BIO_printf(bio_err, "No signer certificate specified\n");
405 } else if (operation == SMIME_DECRYPT) {
406 if (recipfile == NULL && keyfile == NULL) {
408 "No recipient certificate or key specified\n");
411 } else if (operation == SMIME_ENCRYPT) {
413 BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
418 if (!app_passwd(passinarg, NULL, &passin, NULL)) {
419 BIO_printf(bio_err, "Error getting password\n");
425 if (!(operation & SMIME_SIGNERS))
426 flags &= ~PKCS7_DETACHED;
428 if (!(operation & SMIME_OP)) {
429 if (flags & PKCS7_BINARY)
430 outformat = FORMAT_BINARY;
433 if (!(operation & SMIME_IP)) {
434 if (flags & PKCS7_BINARY)
435 informat = FORMAT_BINARY;
438 if (operation == SMIME_ENCRYPT) {
439 if (cipher == NULL) {
440 #ifndef OPENSSL_NO_DES
441 cipher = (EVP_CIPHER *)EVP_des_ede3_cbc();
443 BIO_printf(bio_err, "No cipher selected\n");
447 encerts = sk_X509_new_null();
450 while (*argv != NULL) {
451 cert = load_cert(*argv, FORMAT_UNDEF,
452 "recipient certificate file");
455 sk_X509_push(encerts, cert);
461 if (certfile != NULL) {
462 if (!load_certs(certfile, 0, &other, NULL, "certificates")) {
463 ERR_print_errors(bio_err);
468 if (recipfile != NULL && (operation == SMIME_DECRYPT)) {
469 if ((recip = load_cert(recipfile, FORMAT_UNDEF,
470 "recipient certificate file")) == NULL) {
471 ERR_print_errors(bio_err);
476 if (operation == SMIME_DECRYPT) {
479 } else if (operation == SMIME_SIGN) {
481 keyfile = signerfile;
486 if (keyfile != NULL) {
487 key = load_key(keyfile, keyform, 0, passin, e, "signing key");
492 in = bio_open_default(infile, 'r', informat);
496 if (operation & SMIME_IP) {
499 p7 = PKCS7_new_ex(libctx, app_get0_propq());
501 BIO_printf(bio_err, "Error allocating PKCS7 object\n");
504 if (informat == FORMAT_SMIME) {
505 p7_in = SMIME_read_PKCS7_ex(in, &indata, &p7);
506 } else if (informat == FORMAT_PEM) {
507 p7_in = PEM_read_bio_PKCS7(in, &p7, NULL, NULL);
508 } else if (informat == FORMAT_ASN1) {
509 p7_in = d2i_PKCS7_bio(in, &p7);
511 BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
516 BIO_printf(bio_err, "Error reading S/MIME message\n");
519 if (contfile != NULL) {
521 if ((indata = BIO_new_file(contfile, "rb")) == NULL) {
522 BIO_printf(bio_err, "Can't read content file %s\n", contfile);
528 out = bio_open_default(outfile, 'w', outformat);
532 if (operation == SMIME_VERIFY) {
533 if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
534 CAstore, noCAstore)) == NULL)
536 X509_STORE_set_verify_cb(store, smime_cb);
538 X509_STORE_set1_param(store, vpm);
543 if (operation == SMIME_ENCRYPT) {
545 flags |= PKCS7_STREAM;
546 p7 = PKCS7_encrypt_ex(encerts, in, cipher, flags, libctx, app_get0_propq());
547 } else if (operation & SMIME_SIGNERS) {
550 * If detached data content we only enable streaming if S/MIME output
553 if (operation == SMIME_SIGN) {
554 if (flags & PKCS7_DETACHED) {
555 if (outformat == FORMAT_SMIME)
556 flags |= PKCS7_STREAM;
558 flags |= PKCS7_STREAM;
560 flags |= PKCS7_PARTIAL;
561 p7 = PKCS7_sign_ex(NULL, NULL, other, in, flags, libctx, app_get0_propq());
564 if (flags & PKCS7_NOCERTS) {
565 for (i = 0; i < sk_X509_num(other); i++) {
566 X509 *x = sk_X509_value(other, i);
567 PKCS7_add_certificate(p7, x);
571 flags |= PKCS7_REUSE_DIGEST;
573 for (i = 0; i < sk_OPENSSL_STRING_num(sksigners); i++) {
574 signerfile = sk_OPENSSL_STRING_value(sksigners, i);
575 keyfile = sk_OPENSSL_STRING_value(skkeys, i);
576 signer = load_cert(signerfile, FORMAT_UNDEF, "signer certificate");
579 key = load_key(keyfile, keyform, 0, passin, e, "signing key");
583 if (!PKCS7_sign_add_signer(p7, signer, key, sign_md, flags))
590 /* If not streaming or resigning finalize structure */
591 if ((operation == SMIME_SIGN) && !(flags & PKCS7_STREAM)) {
592 if (!PKCS7_final(p7, in, flags))
598 BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
603 if (operation == SMIME_DECRYPT) {
604 if (!PKCS7_decrypt(p7, key, recip, out, flags)) {
605 BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
608 } else if (operation == SMIME_VERIFY) {
609 STACK_OF(X509) *signers;
610 if (PKCS7_verify(p7, other, store, indata, out, flags))
611 BIO_printf(bio_err, "Verification successful\n");
613 BIO_printf(bio_err, "Verification failure\n");
616 signers = PKCS7_get0_signers(p7, other, flags);
617 if (!save_certs(signerfile, signers)) {
618 BIO_printf(bio_err, "Error writing signers to %s\n", signerfile);
622 sk_X509_free(signers);
623 } else if (operation == SMIME_PK7OUT) {
624 PEM_write_bio_PKCS7(out, p7);
627 BIO_printf(out, "To: %s%s", to, mime_eol);
629 BIO_printf(out, "From: %s%s", from, mime_eol);
631 BIO_printf(out, "Subject: %s%s", subject, mime_eol);
632 if (outformat == FORMAT_SMIME) {
633 if (operation == SMIME_RESIGN)
634 rv = SMIME_write_PKCS7(out, p7, indata, flags);
636 rv = SMIME_write_PKCS7(out, p7, in, flags);
637 } else if (outformat == FORMAT_PEM) {
638 rv = PEM_write_bio_PKCS7_stream(out, p7, in, flags);
639 } else if (outformat == FORMAT_ASN1) {
640 rv = i2d_PKCS7_bio_stream(out, p7, in, flags);
642 BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
646 BIO_printf(bio_err, "Error writing output\n");
654 ERR_print_errors(bio_err);
655 OSSL_STACK_OF_X509_free(encerts);
656 OSSL_STACK_OF_X509_free(other);
657 X509_VERIFY_PARAM_free(vpm);
658 sk_OPENSSL_STRING_free(sksigners);
659 sk_OPENSSL_STRING_free(skkeys);
660 X509_STORE_free(store);
665 EVP_MD_free(sign_md);
666 EVP_CIPHER_free(cipher);
672 OPENSSL_free(passin);
677 static int save_certs(char *signerfile, STACK_OF(X509) *signers)
682 if (signerfile == NULL)
684 tmp = BIO_new_file(signerfile, "w");
687 for (i = 0; i < sk_X509_num(signers); i++)
688 PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
693 /* Minimal callback just to output policy info (if any) */
695 static int smime_cb(int ok, X509_STORE_CTX *ctx)
699 error = X509_STORE_CTX_get_error(ctx);
701 if ((error != X509_V_ERR_NO_EXPLICIT_POLICY)
702 && ((error != X509_V_OK) || (ok != 2)))