xref: /dragonfly/crypto/libressl/apps/openssl/smime.c (revision 72c33676)
1 /* $OpenBSD: smime.c,v 1.10 2018/02/07 05:47:55 jsing Exp $ */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3  * project.
4  */
5 /* ====================================================================
6  * Copyright (c) 1999-2004 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 /* S/MIME utility function */
60 
61 #include <stdio.h>
62 #include <string.h>
63 
64 #include "apps.h"
65 
66 #include <openssl/crypto.h>
67 #include <openssl/err.h>
68 #include <openssl/pem.h>
69 #include <openssl/x509_vfy.h>
70 #include <openssl/x509v3.h>
71 
72 static int save_certs(char *signerfile, STACK_OF(X509) * signers);
73 static int smime_cb(int ok, X509_STORE_CTX * ctx);
74 
75 #define SMIME_OP	0x10
76 #define SMIME_IP	0x20
77 #define SMIME_SIGNERS	0x40
78 #define SMIME_ENCRYPT	(1 | SMIME_OP)
79 #define SMIME_DECRYPT	(2 | SMIME_IP)
80 #define SMIME_SIGN	(3 | SMIME_OP | SMIME_SIGNERS)
81 #define SMIME_VERIFY	(4 | SMIME_IP)
82 #define SMIME_PK7OUT	(5 | SMIME_IP | SMIME_OP)
83 #define SMIME_RESIGN	(6 | SMIME_IP | SMIME_OP | SMIME_SIGNERS)
84 
85 int
86 smime_main(int argc, char **argv)
87 {
88 	int operation = 0;
89 	int ret = 0;
90 	char **args;
91 	const char *inmode = "r", *outmode = "w";
92 	char *infile = NULL, *outfile = NULL;
93 	char *signerfile = NULL, *recipfile = NULL;
94 	STACK_OF(OPENSSL_STRING) * sksigners = NULL, *skkeys = NULL;
95 	char *certfile = NULL, *keyfile = NULL, *contfile = NULL;
96 	const EVP_CIPHER *cipher = NULL;
97 	PKCS7 *p7 = NULL;
98 	X509_STORE *store = NULL;
99 	X509 *cert = NULL, *recip = NULL, *signer = NULL;
100 	EVP_PKEY *key = NULL;
101 	STACK_OF(X509) * encerts = NULL, *other = NULL;
102 	BIO *in = NULL, *out = NULL, *indata = NULL;
103 	int badarg = 0;
104 	int flags = PKCS7_DETACHED;
105 	char *to = NULL, *from = NULL, *subject = NULL;
106 	char *CAfile = NULL, *CApath = NULL;
107 	char *passargin = NULL, *passin = NULL;
108 	int indef = 0;
109 	const EVP_MD *sign_md = NULL;
110 	int informat = FORMAT_SMIME, outformat = FORMAT_SMIME;
111 	int keyform = FORMAT_PEM;
112 
113 	X509_VERIFY_PARAM *vpm = NULL;
114 
115 	if (single_execution) {
116 		if (pledge("stdio cpath wpath rpath tty", NULL) == -1) {
117 			perror("pledge");
118 			exit(1);
119 		}
120 	}
121 
122 	args = argv + 1;
123 	ret = 1;
124 
125 	while (!badarg && *args && *args[0] == '-') {
126 		if (!strcmp(*args, "-encrypt"))
127 			operation = SMIME_ENCRYPT;
128 		else if (!strcmp(*args, "-decrypt"))
129 			operation = SMIME_DECRYPT;
130 		else if (!strcmp(*args, "-sign"))
131 			operation = SMIME_SIGN;
132 		else if (!strcmp(*args, "-resign"))
133 			operation = SMIME_RESIGN;
134 		else if (!strcmp(*args, "-verify"))
135 			operation = SMIME_VERIFY;
136 		else if (!strcmp(*args, "-pk7out"))
137 			operation = SMIME_PK7OUT;
138 #ifndef OPENSSL_NO_DES
139 		else if (!strcmp(*args, "-des3"))
140 			cipher = EVP_des_ede3_cbc();
141 		else if (!strcmp(*args, "-des"))
142 			cipher = EVP_des_cbc();
143 #endif
144 #ifndef OPENSSL_NO_RC2
145 		else if (!strcmp(*args, "-rc2-40"))
146 			cipher = EVP_rc2_40_cbc();
147 		else if (!strcmp(*args, "-rc2-128"))
148 			cipher = EVP_rc2_cbc();
149 		else if (!strcmp(*args, "-rc2-64"))
150 			cipher = EVP_rc2_64_cbc();
151 #endif
152 #ifndef OPENSSL_NO_AES
153 		else if (!strcmp(*args, "-aes128"))
154 			cipher = EVP_aes_128_cbc();
155 		else if (!strcmp(*args, "-aes192"))
156 			cipher = EVP_aes_192_cbc();
157 		else if (!strcmp(*args, "-aes256"))
158 			cipher = EVP_aes_256_cbc();
159 #endif
160 #ifndef OPENSSL_NO_CAMELLIA
161 		else if (!strcmp(*args, "-camellia128"))
162 			cipher = EVP_camellia_128_cbc();
163 		else if (!strcmp(*args, "-camellia192"))
164 			cipher = EVP_camellia_192_cbc();
165 		else if (!strcmp(*args, "-camellia256"))
166 			cipher = EVP_camellia_256_cbc();
167 #endif
168 		else if (!strcmp(*args, "-text"))
169 			flags |= PKCS7_TEXT;
170 		else if (!strcmp(*args, "-nointern"))
171 			flags |= PKCS7_NOINTERN;
172 		else if (!strcmp(*args, "-noverify"))
173 			flags |= PKCS7_NOVERIFY;
174 		else if (!strcmp(*args, "-nochain"))
175 			flags |= PKCS7_NOCHAIN;
176 		else if (!strcmp(*args, "-nocerts"))
177 			flags |= PKCS7_NOCERTS;
178 		else if (!strcmp(*args, "-noattr"))
179 			flags |= PKCS7_NOATTR;
180 		else if (!strcmp(*args, "-nodetach"))
181 			flags &= ~PKCS7_DETACHED;
182 		else if (!strcmp(*args, "-nosmimecap"))
183 			flags |= PKCS7_NOSMIMECAP;
184 		else if (!strcmp(*args, "-binary"))
185 			flags |= PKCS7_BINARY;
186 		else if (!strcmp(*args, "-nosigs"))
187 			flags |= PKCS7_NOSIGS;
188 		else if (!strcmp(*args, "-stream"))
189 			indef = 1;
190 		else if (!strcmp(*args, "-indef"))
191 			indef = 1;
192 		else if (!strcmp(*args, "-noindef"))
193 			indef = 0;
194 		else if (!strcmp(*args, "-nooldmime"))
195 			flags |= PKCS7_NOOLDMIMETYPE;
196 		else if (!strcmp(*args, "-crlfeol"))
197 			flags |= PKCS7_CRLFEOL;
198 		else if (!strcmp(*args, "-passin")) {
199 			if (!args[1])
200 				goto argerr;
201 			passargin = *++args;
202 		} else if (!strcmp(*args, "-to")) {
203 			if (!args[1])
204 				goto argerr;
205 			to = *++args;
206 		} else if (!strcmp(*args, "-from")) {
207 			if (!args[1])
208 				goto argerr;
209 			from = *++args;
210 		} else if (!strcmp(*args, "-subject")) {
211 			if (!args[1])
212 				goto argerr;
213 			subject = *++args;
214 		} else if (!strcmp(*args, "-signer")) {
215 			if (!args[1])
216 				goto argerr;
217 			/* If previous -signer argument add signer to list */
218 
219 			if (signerfile) {
220 				if (!sksigners)
221 					sksigners = sk_OPENSSL_STRING_new_null();
222 				sk_OPENSSL_STRING_push(sksigners, signerfile);
223 				if (!keyfile)
224 					keyfile = signerfile;
225 				if (!skkeys)
226 					skkeys = sk_OPENSSL_STRING_new_null();
227 				sk_OPENSSL_STRING_push(skkeys, keyfile);
228 				keyfile = NULL;
229 			}
230 			signerfile = *++args;
231 		} else if (!strcmp(*args, "-recip")) {
232 			if (!args[1])
233 				goto argerr;
234 			recipfile = *++args;
235 		} else if (!strcmp(*args, "-md")) {
236 			if (!args[1])
237 				goto argerr;
238 			sign_md = EVP_get_digestbyname(*++args);
239 			if (sign_md == NULL) {
240 				BIO_printf(bio_err, "Unknown digest %s\n",
241 				    *args);
242 				goto argerr;
243 			}
244 		} else if (!strcmp(*args, "-inkey")) {
245 			if (!args[1])
246 				goto argerr;
247 			/* If previous -inkey arument add signer to list */
248 			if (keyfile) {
249 				if (!signerfile) {
250 					BIO_puts(bio_err, "Illegal -inkey without -signer\n");
251 					goto argerr;
252 				}
253 				if (!sksigners)
254 					sksigners = sk_OPENSSL_STRING_new_null();
255 				sk_OPENSSL_STRING_push(sksigners, signerfile);
256 				signerfile = NULL;
257 				if (!skkeys)
258 					skkeys = sk_OPENSSL_STRING_new_null();
259 				sk_OPENSSL_STRING_push(skkeys, keyfile);
260 			}
261 			keyfile = *++args;
262 		} else if (!strcmp(*args, "-keyform")) {
263 			if (!args[1])
264 				goto argerr;
265 			keyform = str2fmt(*++args);
266 		} else if (!strcmp(*args, "-certfile")) {
267 			if (!args[1])
268 				goto argerr;
269 			certfile = *++args;
270 		} else if (!strcmp(*args, "-CAfile")) {
271 			if (!args[1])
272 				goto argerr;
273 			CAfile = *++args;
274 		} else if (!strcmp(*args, "-CApath")) {
275 			if (!args[1])
276 				goto argerr;
277 			CApath = *++args;
278 		} else if (!strcmp(*args, "-in")) {
279 			if (!args[1])
280 				goto argerr;
281 			infile = *++args;
282 		} else if (!strcmp(*args, "-inform")) {
283 			if (!args[1])
284 				goto argerr;
285 			informat = str2fmt(*++args);
286 		} else if (!strcmp(*args, "-outform")) {
287 			if (!args[1])
288 				goto argerr;
289 			outformat = str2fmt(*++args);
290 		} else if (!strcmp(*args, "-out")) {
291 			if (!args[1])
292 				goto argerr;
293 			outfile = *++args;
294 		} else if (!strcmp(*args, "-content")) {
295 			if (!args[1])
296 				goto argerr;
297 			contfile = *++args;
298 		} else if (args_verify(&args, NULL, &badarg, bio_err, &vpm))
299 			continue;
300 		else if ((cipher = EVP_get_cipherbyname(*args + 1)) == NULL)
301 			badarg = 1;
302 		args++;
303 	}
304 
305 	if (!(operation & SMIME_SIGNERS) && (skkeys || sksigners)) {
306 		BIO_puts(bio_err, "Multiple signers or keys not allowed\n");
307 		goto argerr;
308 	}
309 	if (operation & SMIME_SIGNERS) {
310 		/* Check to see if any final signer needs to be appended */
311 		if (keyfile && !signerfile) {
312 			BIO_puts(bio_err, "Illegal -inkey without -signer\n");
313 			goto argerr;
314 		}
315 		if (signerfile) {
316 			if (!sksigners)
317 				sksigners = sk_OPENSSL_STRING_new_null();
318 			sk_OPENSSL_STRING_push(sksigners, signerfile);
319 			if (!skkeys)
320 				skkeys = sk_OPENSSL_STRING_new_null();
321 			if (!keyfile)
322 				keyfile = signerfile;
323 			sk_OPENSSL_STRING_push(skkeys, keyfile);
324 		}
325 		if (!sksigners) {
326 			BIO_printf(bio_err, "No signer certificate specified\n");
327 			badarg = 1;
328 		}
329 		signerfile = NULL;
330 		keyfile = NULL;
331 	} else if (operation == SMIME_DECRYPT) {
332 		if (!recipfile && !keyfile) {
333 			BIO_printf(bio_err, "No recipient certificate or key specified\n");
334 			badarg = 1;
335 		}
336 	} else if (operation == SMIME_ENCRYPT) {
337 		if (!*args) {
338 			BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
339 			badarg = 1;
340 		}
341 	} else if (!operation)
342 		badarg = 1;
343 
344 	if (badarg) {
345  argerr:
346 		BIO_printf(bio_err, "Usage smime [options] cert.pem ...\n");
347 		BIO_printf(bio_err, "where options are\n");
348 		BIO_printf(bio_err, "-encrypt       encrypt message\n");
349 		BIO_printf(bio_err, "-decrypt       decrypt encrypted message\n");
350 		BIO_printf(bio_err, "-sign          sign message\n");
351 		BIO_printf(bio_err, "-verify        verify signed message\n");
352 		BIO_printf(bio_err, "-pk7out        output PKCS#7 structure\n");
353 #ifndef OPENSSL_NO_DES
354 		BIO_printf(bio_err, "-des3          encrypt with triple DES\n");
355 		BIO_printf(bio_err, "-des           encrypt with DES\n");
356 #endif
357 #ifndef OPENSSL_NO_RC2
358 		BIO_printf(bio_err, "-rc2-40        encrypt with RC2-40 (default)\n");
359 		BIO_printf(bio_err, "-rc2-64        encrypt with RC2-64\n");
360 		BIO_printf(bio_err, "-rc2-128       encrypt with RC2-128\n");
361 #endif
362 #ifndef OPENSSL_NO_AES
363 		BIO_printf(bio_err, "-aes128, -aes192, -aes256\n");
364 		BIO_printf(bio_err, "               encrypt PEM output with cbc aes\n");
365 #endif
366 #ifndef OPENSSL_NO_CAMELLIA
367 		BIO_printf(bio_err, "-camellia128, -camellia192, -camellia256\n");
368 		BIO_printf(bio_err, "               encrypt PEM output with cbc camellia\n");
369 #endif
370 		BIO_printf(bio_err, "-nointern      don't search certificates in message for signer\n");
371 		BIO_printf(bio_err, "-nosigs        don't verify message signature\n");
372 		BIO_printf(bio_err, "-noverify      don't verify signers certificate\n");
373 		BIO_printf(bio_err, "-nocerts       don't include signers certificate when signing\n");
374 		BIO_printf(bio_err, "-nodetach      use opaque signing\n");
375 		BIO_printf(bio_err, "-noattr        don't include any signed attributes\n");
376 		BIO_printf(bio_err, "-binary        don't translate message to text\n");
377 		BIO_printf(bio_err, "-certfile file other certificates file\n");
378 		BIO_printf(bio_err, "-signer file   signer certificate file\n");
379 		BIO_printf(bio_err, "-recip  file   recipient certificate file for decryption\n");
380 		BIO_printf(bio_err, "-in file       input file\n");
381 		BIO_printf(bio_err, "-inform arg    input format SMIME (default), PEM or DER\n");
382 		BIO_printf(bio_err, "-inkey file    input private key (if not signer or recipient)\n");
383 		BIO_printf(bio_err, "-keyform arg   input private key format (PEM)\n");
384 		BIO_printf(bio_err, "-out file      output file\n");
385 		BIO_printf(bio_err, "-outform arg   output format SMIME (default), PEM or DER\n");
386 		BIO_printf(bio_err, "-content file  supply or override content for detached signature\n");
387 		BIO_printf(bio_err, "-to addr       to address\n");
388 		BIO_printf(bio_err, "-from ad       from address\n");
389 		BIO_printf(bio_err, "-subject s     subject\n");
390 		BIO_printf(bio_err, "-text          include or delete text MIME headers\n");
391 		BIO_printf(bio_err, "-CApath dir    trusted certificates directory\n");
392 		BIO_printf(bio_err, "-CAfile file   trusted certificates file\n");
393 		BIO_printf(bio_err, "-crl_check     check revocation status of signer's certificate using CRLs\n");
394 		BIO_printf(bio_err, "-crl_check_all check revocation status of signer's certificate chain using CRLs\n");
395 		BIO_printf(bio_err, "-passin arg    input file pass phrase source\n");
396 		BIO_printf(bio_err, "cert.pem       recipient certificate(s) for encryption\n");
397 		goto end;
398 	}
399 
400 	if (!app_passwd(bio_err, passargin, NULL, &passin, NULL)) {
401 		BIO_printf(bio_err, "Error getting password\n");
402 		goto end;
403 	}
404 	ret = 2;
405 
406 	if (!(operation & SMIME_SIGNERS))
407 		flags &= ~PKCS7_DETACHED;
408 
409 	if (operation & SMIME_OP) {
410 		if (outformat == FORMAT_ASN1)
411 			outmode = "wb";
412 	} else {
413 		if (flags & PKCS7_BINARY)
414 			outmode = "wb";
415 	}
416 
417 	if (operation & SMIME_IP) {
418 		if (informat == FORMAT_ASN1)
419 			inmode = "rb";
420 	} else {
421 		if (flags & PKCS7_BINARY)
422 			inmode = "rb";
423 	}
424 
425 	if (operation == SMIME_ENCRYPT) {
426 		if (!cipher) {
427 #ifndef OPENSSL_NO_RC2
428 			cipher = EVP_rc2_40_cbc();
429 #else
430 			BIO_printf(bio_err, "No cipher selected\n");
431 			goto end;
432 #endif
433 		}
434 		encerts = sk_X509_new_null();
435 		while (*args) {
436 			if (!(cert = load_cert(bio_err, *args, FORMAT_PEM,
437 			    NULL, "recipient certificate file"))) {
438 				goto end;
439 			}
440 			sk_X509_push(encerts, cert);
441 			cert = NULL;
442 			args++;
443 		}
444 	}
445 	if (certfile) {
446 		if (!(other = load_certs(bio_err, certfile, FORMAT_PEM, NULL,
447 		    "certificate file"))) {
448 			ERR_print_errors(bio_err);
449 			goto end;
450 		}
451 	}
452 	if (recipfile && (operation == SMIME_DECRYPT)) {
453 		if (!(recip = load_cert(bio_err, recipfile, FORMAT_PEM, NULL,
454 		    "recipient certificate file"))) {
455 			ERR_print_errors(bio_err);
456 			goto end;
457 		}
458 	}
459 	if (operation == SMIME_DECRYPT) {
460 		if (!keyfile)
461 			keyfile = recipfile;
462 	} else if (operation == SMIME_SIGN) {
463 		if (!keyfile)
464 			keyfile = signerfile;
465 	} else
466 		keyfile = NULL;
467 
468 	if (keyfile) {
469 		key = load_key(bio_err, keyfile, keyform, 0, passin,
470 		    "signing key file");
471 		if (!key)
472 			goto end;
473 	}
474 	if (infile) {
475 		if (!(in = BIO_new_file(infile, inmode))) {
476 			BIO_printf(bio_err,
477 			    "Can't open input file %s\n", infile);
478 			goto end;
479 		}
480 	} else
481 		in = BIO_new_fp(stdin, BIO_NOCLOSE);
482 
483 	if (operation & SMIME_IP) {
484 		if (informat == FORMAT_SMIME)
485 			p7 = SMIME_read_PKCS7(in, &indata);
486 		else if (informat == FORMAT_PEM)
487 			p7 = PEM_read_bio_PKCS7(in, NULL, NULL, NULL);
488 		else if (informat == FORMAT_ASN1)
489 			p7 = d2i_PKCS7_bio(in, NULL);
490 		else {
491 			BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
492 			goto end;
493 		}
494 
495 		if (!p7) {
496 			BIO_printf(bio_err, "Error reading S/MIME message\n");
497 			goto end;
498 		}
499 		if (contfile) {
500 			BIO_free(indata);
501 			if (!(indata = BIO_new_file(contfile, "rb"))) {
502 				BIO_printf(bio_err, "Can't read content file %s\n", contfile);
503 				goto end;
504 			}
505 		}
506 	}
507 	if (outfile) {
508 		if (!(out = BIO_new_file(outfile, outmode))) {
509 			BIO_printf(bio_err,
510 			    "Can't open output file %s\n", outfile);
511 			goto end;
512 		}
513 	} else {
514 		out = BIO_new_fp(stdout, BIO_NOCLOSE);
515 	}
516 
517 	if (operation == SMIME_VERIFY) {
518 		if (!(store = setup_verify(bio_err, CAfile, CApath)))
519 			goto end;
520 		X509_STORE_set_verify_cb(store, smime_cb);
521 		if (vpm)
522 			X509_STORE_set1_param(store, vpm);
523 	}
524 	ret = 3;
525 
526 	if (operation == SMIME_ENCRYPT) {
527 		if (indef)
528 			flags |= PKCS7_STREAM;
529 		p7 = PKCS7_encrypt(encerts, in, cipher, flags);
530 	} else if (operation & SMIME_SIGNERS) {
531 		int i;
532 		/*
533 		 * If detached data content we only enable streaming if
534 		 * S/MIME output format.
535 		 */
536 		if (operation == SMIME_SIGN) {
537 			if (flags & PKCS7_DETACHED) {
538 				if (outformat == FORMAT_SMIME)
539 					flags |= PKCS7_STREAM;
540 			} else if (indef)
541 				flags |= PKCS7_STREAM;
542 			flags |= PKCS7_PARTIAL;
543 			p7 = PKCS7_sign(NULL, NULL, other, in, flags);
544 			if (!p7)
545 				goto end;
546 		} else
547 			flags |= PKCS7_REUSE_DIGEST;
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(bio_err, signerfile, FORMAT_PEM, NULL,
552 			    "signer certificate");
553 			if (!signer)
554 				goto end;
555 			key = load_key(bio_err, keyfile, keyform, 0, passin,
556 			    "signing key file");
557 			if (!key)
558 				goto end;
559 			if (!PKCS7_sign_add_signer(p7, signer, key,
560 				sign_md, flags))
561 				goto end;
562 			X509_free(signer);
563 			signer = NULL;
564 			EVP_PKEY_free(key);
565 			key = NULL;
566 		}
567 		/* If not streaming or resigning finalize structure */
568 		if ((operation == SMIME_SIGN) && !(flags & PKCS7_STREAM)) {
569 			if (!PKCS7_final(p7, in, flags))
570 				goto end;
571 		}
572 	}
573 	if (!p7) {
574 		BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
575 		goto end;
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",
594 			    signerfile);
595 			ret = 5;
596 			goto end;
597 		}
598 		sk_X509_free(signers);
599 	} else if (operation == SMIME_PK7OUT)
600 		PEM_write_bio_PKCS7(out, p7);
601 	else {
602 		if (to)
603 			BIO_printf(out, "To: %s\n", to);
604 		if (from)
605 			BIO_printf(out, "From: %s\n", from);
606 		if (subject)
607 			BIO_printf(out, "Subject: %s\n", subject);
608 		if (outformat == FORMAT_SMIME) {
609 			if (operation == SMIME_RESIGN)
610 				SMIME_write_PKCS7(out, p7, indata, flags);
611 			else
612 				SMIME_write_PKCS7(out, p7, in, flags);
613 		} else if (outformat == FORMAT_PEM)
614 			PEM_write_bio_PKCS7_stream(out, p7, in, flags);
615 		else if (outformat == FORMAT_ASN1)
616 			i2d_PKCS7_bio_stream(out, p7, in, flags);
617 		else {
618 			BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
619 			goto end;
620 		}
621 	}
622 	ret = 0;
623  end:
624 	if (ret)
625 		ERR_print_errors(bio_err);
626 	sk_X509_pop_free(encerts, X509_free);
627 	sk_X509_pop_free(other, X509_free);
628 	X509_VERIFY_PARAM_free(vpm);
629 	sk_OPENSSL_STRING_free(sksigners);
630 	sk_OPENSSL_STRING_free(skkeys);
631 	X509_STORE_free(store);
632 	X509_free(cert);
633 	X509_free(recip);
634 	X509_free(signer);
635 	EVP_PKEY_free(key);
636 	PKCS7_free(p7);
637 	BIO_free(in);
638 	BIO_free(indata);
639 	BIO_free_all(out);
640 	free(passin);
641 
642 	return (ret);
643 }
644 
645 static int
646 save_certs(char *signerfile, STACK_OF(X509) * signers)
647 {
648 	int i;
649 	BIO *tmp;
650 	if (!signerfile)
651 		return 1;
652 	tmp = BIO_new_file(signerfile, "w");
653 	if (!tmp)
654 		return 0;
655 	for (i = 0; i < sk_X509_num(signers); i++)
656 		PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
657 	BIO_free(tmp);
658 	return 1;
659 }
660 
661 
662 /* Minimal callback just to output policy info (if any) */
663 
664 static int
665 smime_cb(int ok, X509_STORE_CTX * ctx)
666 {
667 	int error;
668 
669 	error = X509_STORE_CTX_get_error(ctx);
670 
671 	if ((error != X509_V_ERR_NO_EXPLICIT_POLICY)
672 	    && ((error != X509_V_OK) || (ok != 2)))
673 		return ok;
674 
675 	policies_print(NULL, ctx);
676 
677 	return ok;
678 
679 }
680