xref: /openbsd/usr.bin/openssl/smime.c (revision cecf84d4)
1 /* $OpenBSD: smime.c,v 1.2 2015/02/08 10:22:45 doug 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 smime_main(int, char **);
86 
87 int
88 smime_main(int argc, char **argv)
89 {
90 	ENGINE *e = NULL;
91 	int operation = 0;
92 	int ret = 0;
93 	char **args;
94 	const char *inmode = "r", *outmode = "w";
95 	char *infile = NULL, *outfile = NULL;
96 	char *signerfile = NULL, *recipfile = NULL;
97 	STACK_OF(OPENSSL_STRING) * sksigners = NULL, *skkeys = NULL;
98 	char *certfile = NULL, *keyfile = NULL, *contfile = NULL;
99 	const EVP_CIPHER *cipher = NULL;
100 	PKCS7 *p7 = NULL;
101 	X509_STORE *store = NULL;
102 	X509 *cert = NULL, *recip = NULL, *signer = NULL;
103 	EVP_PKEY *key = NULL;
104 	STACK_OF(X509) * encerts = NULL, *other = NULL;
105 	BIO *in = NULL, *out = NULL, *indata = NULL;
106 	int badarg = 0;
107 	int flags = PKCS7_DETACHED;
108 	char *to = NULL, *from = NULL, *subject = NULL;
109 	char *CAfile = NULL, *CApath = NULL;
110 	char *passargin = NULL, *passin = NULL;
111 	int indef = 0;
112 	const EVP_MD *sign_md = NULL;
113 	int informat = FORMAT_SMIME, outformat = FORMAT_SMIME;
114 	int keyform = FORMAT_PEM;
115 #ifndef OPENSSL_NO_ENGINE
116 	char *engine = NULL;
117 #endif
118 
119 	X509_VERIFY_PARAM *vpm = NULL;
120 
121 	args = argv + 1;
122 	ret = 1;
123 
124 	while (!badarg && *args && *args[0] == '-') {
125 		if (!strcmp(*args, "-encrypt"))
126 			operation = SMIME_ENCRYPT;
127 		else if (!strcmp(*args, "-decrypt"))
128 			operation = SMIME_DECRYPT;
129 		else if (!strcmp(*args, "-sign"))
130 			operation = SMIME_SIGN;
131 		else if (!strcmp(*args, "-resign"))
132 			operation = SMIME_RESIGN;
133 		else if (!strcmp(*args, "-verify"))
134 			operation = SMIME_VERIFY;
135 		else if (!strcmp(*args, "-pk7out"))
136 			operation = SMIME_PK7OUT;
137 #ifndef OPENSSL_NO_DES
138 		else if (!strcmp(*args, "-des3"))
139 			cipher = EVP_des_ede3_cbc();
140 		else if (!strcmp(*args, "-des"))
141 			cipher = EVP_des_cbc();
142 #endif
143 #ifndef OPENSSL_NO_RC2
144 		else if (!strcmp(*args, "-rc2-40"))
145 			cipher = EVP_rc2_40_cbc();
146 		else if (!strcmp(*args, "-rc2-128"))
147 			cipher = EVP_rc2_cbc();
148 		else if (!strcmp(*args, "-rc2-64"))
149 			cipher = EVP_rc2_64_cbc();
150 #endif
151 #ifndef OPENSSL_NO_AES
152 		else if (!strcmp(*args, "-aes128"))
153 			cipher = EVP_aes_128_cbc();
154 		else if (!strcmp(*args, "-aes192"))
155 			cipher = EVP_aes_192_cbc();
156 		else if (!strcmp(*args, "-aes256"))
157 			cipher = EVP_aes_256_cbc();
158 #endif
159 #ifndef OPENSSL_NO_CAMELLIA
160 		else if (!strcmp(*args, "-camellia128"))
161 			cipher = EVP_camellia_128_cbc();
162 		else if (!strcmp(*args, "-camellia192"))
163 			cipher = EVP_camellia_192_cbc();
164 		else if (!strcmp(*args, "-camellia256"))
165 			cipher = EVP_camellia_256_cbc();
166 #endif
167 		else if (!strcmp(*args, "-text"))
168 			flags |= PKCS7_TEXT;
169 		else if (!strcmp(*args, "-nointern"))
170 			flags |= PKCS7_NOINTERN;
171 		else if (!strcmp(*args, "-noverify"))
172 			flags |= PKCS7_NOVERIFY;
173 		else if (!strcmp(*args, "-nochain"))
174 			flags |= PKCS7_NOCHAIN;
175 		else if (!strcmp(*args, "-nocerts"))
176 			flags |= PKCS7_NOCERTS;
177 		else if (!strcmp(*args, "-noattr"))
178 			flags |= PKCS7_NOATTR;
179 		else if (!strcmp(*args, "-nodetach"))
180 			flags &= ~PKCS7_DETACHED;
181 		else if (!strcmp(*args, "-nosmimecap"))
182 			flags |= PKCS7_NOSMIMECAP;
183 		else if (!strcmp(*args, "-binary"))
184 			flags |= PKCS7_BINARY;
185 		else if (!strcmp(*args, "-nosigs"))
186 			flags |= PKCS7_NOSIGS;
187 		else if (!strcmp(*args, "-stream"))
188 			indef = 1;
189 		else if (!strcmp(*args, "-indef"))
190 			indef = 1;
191 		else if (!strcmp(*args, "-noindef"))
192 			indef = 0;
193 		else if (!strcmp(*args, "-nooldmime"))
194 			flags |= PKCS7_NOOLDMIMETYPE;
195 		else if (!strcmp(*args, "-crlfeol"))
196 			flags |= PKCS7_CRLFEOL;
197 #ifndef OPENSSL_NO_ENGINE
198 		else if (!strcmp(*args, "-engine")) {
199 			if (!args[1])
200 				goto argerr;
201 			engine = *++args;
202 		}
203 #endif
204 		else if (!strcmp(*args, "-passin")) {
205 			if (!args[1])
206 				goto argerr;
207 			passargin = *++args;
208 		} else if (!strcmp(*args, "-to")) {
209 			if (!args[1])
210 				goto argerr;
211 			to = *++args;
212 		} else if (!strcmp(*args, "-from")) {
213 			if (!args[1])
214 				goto argerr;
215 			from = *++args;
216 		} else if (!strcmp(*args, "-subject")) {
217 			if (!args[1])
218 				goto argerr;
219 			subject = *++args;
220 		} else if (!strcmp(*args, "-signer")) {
221 			if (!args[1])
222 				goto argerr;
223 			/* If previous -signer argument add signer to list */
224 
225 			if (signerfile) {
226 				if (!sksigners)
227 					sksigners = sk_OPENSSL_STRING_new_null();
228 				sk_OPENSSL_STRING_push(sksigners, signerfile);
229 				if (!keyfile)
230 					keyfile = signerfile;
231 				if (!skkeys)
232 					skkeys = sk_OPENSSL_STRING_new_null();
233 				sk_OPENSSL_STRING_push(skkeys, keyfile);
234 				keyfile = NULL;
235 			}
236 			signerfile = *++args;
237 		} else if (!strcmp(*args, "-recip")) {
238 			if (!args[1])
239 				goto argerr;
240 			recipfile = *++args;
241 		} else if (!strcmp(*args, "-md")) {
242 			if (!args[1])
243 				goto argerr;
244 			sign_md = EVP_get_digestbyname(*++args);
245 			if (sign_md == NULL) {
246 				BIO_printf(bio_err, "Unknown digest %s\n",
247 				    *args);
248 				goto argerr;
249 			}
250 		} else if (!strcmp(*args, "-inkey")) {
251 			if (!args[1])
252 				goto argerr;
253 			/* If previous -inkey arument add signer to list */
254 			if (keyfile) {
255 				if (!signerfile) {
256 					BIO_puts(bio_err, "Illegal -inkey without -signer\n");
257 					goto argerr;
258 				}
259 				if (!sksigners)
260 					sksigners = sk_OPENSSL_STRING_new_null();
261 				sk_OPENSSL_STRING_push(sksigners, signerfile);
262 				signerfile = NULL;
263 				if (!skkeys)
264 					skkeys = sk_OPENSSL_STRING_new_null();
265 				sk_OPENSSL_STRING_push(skkeys, keyfile);
266 			}
267 			keyfile = *++args;
268 		} else if (!strcmp(*args, "-keyform")) {
269 			if (!args[1])
270 				goto argerr;
271 			keyform = str2fmt(*++args);
272 		} else if (!strcmp(*args, "-certfile")) {
273 			if (!args[1])
274 				goto argerr;
275 			certfile = *++args;
276 		} else if (!strcmp(*args, "-CAfile")) {
277 			if (!args[1])
278 				goto argerr;
279 			CAfile = *++args;
280 		} else if (!strcmp(*args, "-CApath")) {
281 			if (!args[1])
282 				goto argerr;
283 			CApath = *++args;
284 		} else if (!strcmp(*args, "-in")) {
285 			if (!args[1])
286 				goto argerr;
287 			infile = *++args;
288 		} else if (!strcmp(*args, "-inform")) {
289 			if (!args[1])
290 				goto argerr;
291 			informat = str2fmt(*++args);
292 		} else if (!strcmp(*args, "-outform")) {
293 			if (!args[1])
294 				goto argerr;
295 			outformat = str2fmt(*++args);
296 		} else if (!strcmp(*args, "-out")) {
297 			if (!args[1])
298 				goto argerr;
299 			outfile = *++args;
300 		} else if (!strcmp(*args, "-content")) {
301 			if (!args[1])
302 				goto argerr;
303 			contfile = *++args;
304 		} else if (args_verify(&args, NULL, &badarg, bio_err, &vpm))
305 			continue;
306 		else if ((cipher = EVP_get_cipherbyname(*args + 1)) == NULL)
307 			badarg = 1;
308 		args++;
309 	}
310 
311 	if (!(operation & SMIME_SIGNERS) && (skkeys || sksigners)) {
312 		BIO_puts(bio_err, "Multiple signers or keys not allowed\n");
313 		goto argerr;
314 	}
315 	if (operation & SMIME_SIGNERS) {
316 		/* Check to see if any final signer needs to be appended */
317 		if (keyfile && !signerfile) {
318 			BIO_puts(bio_err, "Illegal -inkey without -signer\n");
319 			goto argerr;
320 		}
321 		if (signerfile) {
322 			if (!sksigners)
323 				sksigners = sk_OPENSSL_STRING_new_null();
324 			sk_OPENSSL_STRING_push(sksigners, signerfile);
325 			if (!skkeys)
326 				skkeys = sk_OPENSSL_STRING_new_null();
327 			if (!keyfile)
328 				keyfile = signerfile;
329 			sk_OPENSSL_STRING_push(skkeys, keyfile);
330 		}
331 		if (!sksigners) {
332 			BIO_printf(bio_err, "No signer certificate specified\n");
333 			badarg = 1;
334 		}
335 		signerfile = NULL;
336 		keyfile = NULL;
337 	} else if (operation == SMIME_DECRYPT) {
338 		if (!recipfile && !keyfile) {
339 			BIO_printf(bio_err, "No recipient certificate or key specified\n");
340 			badarg = 1;
341 		}
342 	} else if (operation == SMIME_ENCRYPT) {
343 		if (!*args) {
344 			BIO_printf(bio_err, "No recipient(s) certificate(s) specified\n");
345 			badarg = 1;
346 		}
347 	} else if (!operation)
348 		badarg = 1;
349 
350 	if (badarg) {
351 argerr:
352 		BIO_printf(bio_err, "Usage smime [options] cert.pem ...\n");
353 		BIO_printf(bio_err, "where options are\n");
354 		BIO_printf(bio_err, "-encrypt       encrypt message\n");
355 		BIO_printf(bio_err, "-decrypt       decrypt encrypted message\n");
356 		BIO_printf(bio_err, "-sign          sign message\n");
357 		BIO_printf(bio_err, "-verify        verify signed message\n");
358 		BIO_printf(bio_err, "-pk7out        output PKCS#7 structure\n");
359 #ifndef OPENSSL_NO_DES
360 		BIO_printf(bio_err, "-des3          encrypt with triple DES\n");
361 		BIO_printf(bio_err, "-des           encrypt with DES\n");
362 #endif
363 #ifndef OPENSSL_NO_RC2
364 		BIO_printf(bio_err, "-rc2-40        encrypt with RC2-40 (default)\n");
365 		BIO_printf(bio_err, "-rc2-64        encrypt with RC2-64\n");
366 		BIO_printf(bio_err, "-rc2-128       encrypt with RC2-128\n");
367 #endif
368 #ifndef OPENSSL_NO_AES
369 		BIO_printf(bio_err, "-aes128, -aes192, -aes256\n");
370 		BIO_printf(bio_err, "               encrypt PEM output with cbc aes\n");
371 #endif
372 #ifndef OPENSSL_NO_CAMELLIA
373 		BIO_printf(bio_err, "-camellia128, -camellia192, -camellia256\n");
374 		BIO_printf(bio_err, "               encrypt PEM output with cbc camellia\n");
375 #endif
376 		BIO_printf(bio_err, "-nointern      don't search certificates in message for signer\n");
377 		BIO_printf(bio_err, "-nosigs        don't verify message signature\n");
378 		BIO_printf(bio_err, "-noverify      don't verify signers certificate\n");
379 		BIO_printf(bio_err, "-nocerts       don't include signers certificate when signing\n");
380 		BIO_printf(bio_err, "-nodetach      use opaque signing\n");
381 		BIO_printf(bio_err, "-noattr        don't include any signed attributes\n");
382 		BIO_printf(bio_err, "-binary        don't translate message to text\n");
383 		BIO_printf(bio_err, "-certfile file other certificates file\n");
384 		BIO_printf(bio_err, "-signer file   signer certificate file\n");
385 		BIO_printf(bio_err, "-recip  file   recipient certificate file for decryption\n");
386 		BIO_printf(bio_err, "-in file       input file\n");
387 		BIO_printf(bio_err, "-inform arg    input format SMIME (default), PEM or DER\n");
388 		BIO_printf(bio_err, "-inkey file    input private key (if not signer or recipient)\n");
389 		BIO_printf(bio_err, "-keyform arg   input private key format (PEM or ENGINE)\n");
390 		BIO_printf(bio_err, "-out file      output file\n");
391 		BIO_printf(bio_err, "-outform arg   output format SMIME (default), PEM or DER\n");
392 		BIO_printf(bio_err, "-content file  supply or override content for detached signature\n");
393 		BIO_printf(bio_err, "-to addr       to address\n");
394 		BIO_printf(bio_err, "-from ad       from address\n");
395 		BIO_printf(bio_err, "-subject s     subject\n");
396 		BIO_printf(bio_err, "-text          include or delete text MIME headers\n");
397 		BIO_printf(bio_err, "-CApath dir    trusted certificates directory\n");
398 		BIO_printf(bio_err, "-CAfile file   trusted certificates file\n");
399 		BIO_printf(bio_err, "-crl_check     check revocation status of signer's certificate using CRLs\n");
400 		BIO_printf(bio_err, "-crl_check_all check revocation status of signer's certificate chain using CRLs\n");
401 #ifndef OPENSSL_NO_ENGINE
402 		BIO_printf(bio_err, "-engine e      use engine e, possibly a hardware device.\n");
403 #endif
404 		BIO_printf(bio_err, "-passin arg    input file pass phrase source\n");
405 		BIO_printf(bio_err, "cert.pem       recipient certificate(s) for encryption\n");
406 		goto end;
407 	}
408 #ifndef OPENSSL_NO_ENGINE
409 	e = setup_engine(bio_err, engine, 0);
410 #endif
411 
412 	if (!app_passwd(bio_err, passargin, NULL, &passin, NULL)) {
413 		BIO_printf(bio_err, "Error getting password\n");
414 		goto end;
415 	}
416 	ret = 2;
417 
418 	if (!(operation & SMIME_SIGNERS))
419 		flags &= ~PKCS7_DETACHED;
420 
421 	if (operation & SMIME_OP) {
422 		if (outformat == FORMAT_ASN1)
423 			outmode = "wb";
424 	} else {
425 		if (flags & PKCS7_BINARY)
426 			outmode = "wb";
427 	}
428 
429 	if (operation & SMIME_IP) {
430 		if (informat == FORMAT_ASN1)
431 			inmode = "rb";
432 	} else {
433 		if (flags & PKCS7_BINARY)
434 			inmode = "rb";
435 	}
436 
437 	if (operation == SMIME_ENCRYPT) {
438 		if (!cipher) {
439 #ifndef OPENSSL_NO_RC2
440 			cipher = EVP_rc2_40_cbc();
441 #else
442 			BIO_printf(bio_err, "No cipher selected\n");
443 			goto end;
444 #endif
445 		}
446 		encerts = sk_X509_new_null();
447 		while (*args) {
448 			if (!(cert = load_cert(bio_err, *args, FORMAT_PEM,
449 			    NULL, e, "recipient certificate file"))) {
450 				goto end;
451 			}
452 			sk_X509_push(encerts, cert);
453 			cert = NULL;
454 			args++;
455 		}
456 	}
457 	if (certfile) {
458 		if (!(other = load_certs(bio_err, certfile, FORMAT_PEM, NULL,
459 			    e, "certificate file"))) {
460 			ERR_print_errors(bio_err);
461 			goto end;
462 		}
463 	}
464 	if (recipfile && (operation == SMIME_DECRYPT)) {
465 		if (!(recip = load_cert(bio_err, recipfile, FORMAT_PEM, NULL,
466 			    e, "recipient certificate file"))) {
467 			ERR_print_errors(bio_err);
468 			goto end;
469 		}
470 	}
471 	if (operation == SMIME_DECRYPT) {
472 		if (!keyfile)
473 			keyfile = recipfile;
474 	} else if (operation == SMIME_SIGN) {
475 		if (!keyfile)
476 			keyfile = signerfile;
477 	} else
478 		keyfile = NULL;
479 
480 	if (keyfile) {
481 		key = load_key(bio_err, keyfile, keyform, 0, passin, e,
482 		    "signing key file");
483 		if (!key)
484 			goto end;
485 	}
486 	if (infile) {
487 		if (!(in = BIO_new_file(infile, inmode))) {
488 			BIO_printf(bio_err,
489 			    "Can't open input file %s\n", infile);
490 			goto end;
491 		}
492 	} else
493 		in = BIO_new_fp(stdin, BIO_NOCLOSE);
494 
495 	if (operation & SMIME_IP) {
496 		if (informat == FORMAT_SMIME)
497 			p7 = SMIME_read_PKCS7(in, &indata);
498 		else if (informat == FORMAT_PEM)
499 			p7 = PEM_read_bio_PKCS7(in, NULL, NULL, NULL);
500 		else if (informat == FORMAT_ASN1)
501 			p7 = d2i_PKCS7_bio(in, NULL);
502 		else {
503 			BIO_printf(bio_err, "Bad input format for PKCS#7 file\n");
504 			goto end;
505 		}
506 
507 		if (!p7) {
508 			BIO_printf(bio_err, "Error reading S/MIME message\n");
509 			goto end;
510 		}
511 		if (contfile) {
512 			BIO_free(indata);
513 			if (!(indata = BIO_new_file(contfile, "rb"))) {
514 				BIO_printf(bio_err, "Can't read content file %s\n", contfile);
515 				goto end;
516 			}
517 		}
518 	}
519 	if (outfile) {
520 		if (!(out = BIO_new_file(outfile, outmode))) {
521 			BIO_printf(bio_err,
522 			    "Can't open output file %s\n", outfile);
523 			goto end;
524 		}
525 	} else {
526 		out = BIO_new_fp(stdout, BIO_NOCLOSE);
527 	}
528 
529 	if (operation == SMIME_VERIFY) {
530 		if (!(store = setup_verify(bio_err, CAfile, CApath)))
531 			goto end;
532 		X509_STORE_set_verify_cb(store, smime_cb);
533 		if (vpm)
534 			X509_STORE_set1_param(store, vpm);
535 	}
536 	ret = 3;
537 
538 	if (operation == SMIME_ENCRYPT) {
539 		if (indef)
540 			flags |= PKCS7_STREAM;
541 		p7 = PKCS7_encrypt(encerts, in, cipher, flags);
542 	} else if (operation & SMIME_SIGNERS) {
543 		int i;
544 		/*
545 		 * If detached data content we only enable streaming if
546 		 * S/MIME output format.
547 		 */
548 		if (operation == SMIME_SIGN) {
549 			if (flags & PKCS7_DETACHED) {
550 				if (outformat == FORMAT_SMIME)
551 					flags |= PKCS7_STREAM;
552 			} else if (indef)
553 				flags |= PKCS7_STREAM;
554 			flags |= PKCS7_PARTIAL;
555 			p7 = PKCS7_sign(NULL, NULL, other, in, flags);
556 			if (!p7)
557 				goto end;
558 		} else
559 			flags |= PKCS7_REUSE_DIGEST;
560 		for (i = 0; i < sk_OPENSSL_STRING_num(sksigners); i++) {
561 			signerfile = sk_OPENSSL_STRING_value(sksigners, i);
562 			keyfile = sk_OPENSSL_STRING_value(skkeys, i);
563 			signer = load_cert(bio_err, signerfile, FORMAT_PEM, NULL,
564 			    e, "signer certificate");
565 			if (!signer)
566 				goto end;
567 			key = load_key(bio_err, keyfile, keyform, 0, passin, e,
568 			    "signing key file");
569 			if (!key)
570 				goto end;
571 			if (!PKCS7_sign_add_signer(p7, signer, key,
572 				sign_md, flags))
573 				goto end;
574 			X509_free(signer);
575 			signer = NULL;
576 			EVP_PKEY_free(key);
577 			key = NULL;
578 		}
579 		/* If not streaming or resigning finalize structure */
580 		if ((operation == SMIME_SIGN) && !(flags & PKCS7_STREAM)) {
581 			if (!PKCS7_final(p7, in, flags))
582 				goto end;
583 		}
584 	}
585 	if (!p7) {
586 		BIO_printf(bio_err, "Error creating PKCS#7 structure\n");
587 		goto end;
588 	}
589 	ret = 4;
590 	if (operation == SMIME_DECRYPT) {
591 		if (!PKCS7_decrypt(p7, key, recip, out, flags)) {
592 			BIO_printf(bio_err, "Error decrypting PKCS#7 structure\n");
593 			goto end;
594 		}
595 	} else if (operation == SMIME_VERIFY) {
596 		STACK_OF(X509) * signers;
597 		if (PKCS7_verify(p7, other, store, indata, out, flags))
598 			BIO_printf(bio_err, "Verification successful\n");
599 		else {
600 			BIO_printf(bio_err, "Verification failure\n");
601 			goto end;
602 		}
603 		signers = PKCS7_get0_signers(p7, other, flags);
604 		if (!save_certs(signerfile, signers)) {
605 			BIO_printf(bio_err, "Error writing signers to %s\n",
606 			    signerfile);
607 			ret = 5;
608 			goto end;
609 		}
610 		sk_X509_free(signers);
611 	} else if (operation == SMIME_PK7OUT)
612 		PEM_write_bio_PKCS7(out, p7);
613 	else {
614 		if (to)
615 			BIO_printf(out, "To: %s\n", to);
616 		if (from)
617 			BIO_printf(out, "From: %s\n", from);
618 		if (subject)
619 			BIO_printf(out, "Subject: %s\n", subject);
620 		if (outformat == FORMAT_SMIME) {
621 			if (operation == SMIME_RESIGN)
622 				SMIME_write_PKCS7(out, p7, indata, flags);
623 			else
624 				SMIME_write_PKCS7(out, p7, in, flags);
625 		} else if (outformat == FORMAT_PEM)
626 			PEM_write_bio_PKCS7_stream(out, p7, in, flags);
627 		else if (outformat == FORMAT_ASN1)
628 			i2d_PKCS7_bio_stream(out, p7, in, flags);
629 		else {
630 			BIO_printf(bio_err, "Bad output format for PKCS#7 file\n");
631 			goto end;
632 		}
633 	}
634 	ret = 0;
635 end:
636 	if (ret)
637 		ERR_print_errors(bio_err);
638 	sk_X509_pop_free(encerts, X509_free);
639 	sk_X509_pop_free(other, X509_free);
640 	if (vpm)
641 		X509_VERIFY_PARAM_free(vpm);
642 	if (sksigners)
643 		sk_OPENSSL_STRING_free(sksigners);
644 	if (skkeys)
645 		sk_OPENSSL_STRING_free(skkeys);
646 	X509_STORE_free(store);
647 	X509_free(cert);
648 	X509_free(recip);
649 	X509_free(signer);
650 	EVP_PKEY_free(key);
651 	PKCS7_free(p7);
652 	BIO_free(in);
653 	BIO_free(indata);
654 	BIO_free_all(out);
655 	free(passin);
656 
657 	return (ret);
658 }
659 
660 static int
661 save_certs(char *signerfile, STACK_OF(X509) * signers)
662 {
663 	int i;
664 	BIO *tmp;
665 	if (!signerfile)
666 		return 1;
667 	tmp = BIO_new_file(signerfile, "w");
668 	if (!tmp)
669 		return 0;
670 	for (i = 0; i < sk_X509_num(signers); i++)
671 		PEM_write_bio_X509(tmp, sk_X509_value(signers, i));
672 	BIO_free(tmp);
673 	return 1;
674 }
675 
676 
677 /* Minimal callback just to output policy info (if any) */
678 
679 static int
680 smime_cb(int ok, X509_STORE_CTX * ctx)
681 {
682 	int error;
683 
684 	error = X509_STORE_CTX_get_error(ctx);
685 
686 	if ((error != X509_V_ERR_NO_EXPLICIT_POLICY)
687 	    && ((error != X509_V_OK) || (ok != 2)))
688 		return ok;
689 
690 	policies_print(NULL, ctx);
691 
692 	return ok;
693 
694 }
695