1 /* $OpenBSD: pk7_smime.c,v 1.22 2017/01/29 17:49:23 beck 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 /* Simple PKCS#7 processing functions */
60
61 #include <stdio.h>
62
63 #include <openssl/err.h>
64 #include <openssl/x509.h>
65 #include <openssl/x509v3.h>
66
67 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si);
68
69 PKCS7 *
PKCS7_sign(X509 * signcert,EVP_PKEY * pkey,STACK_OF (X509)* certs,BIO * data,int flags)70 PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs, BIO *data,
71 int flags)
72 {
73 PKCS7 *p7;
74 int i;
75
76 if (!(p7 = PKCS7_new())) {
77 PKCS7error(ERR_R_MALLOC_FAILURE);
78 return NULL;
79 }
80
81 if (!PKCS7_set_type(p7, NID_pkcs7_signed))
82 goto err;
83
84 if (!PKCS7_content_new(p7, NID_pkcs7_data))
85 goto err;
86
87 if (pkey && !PKCS7_sign_add_signer(p7, signcert, pkey, NULL, flags)) {
88 PKCS7error(PKCS7_R_PKCS7_ADD_SIGNER_ERROR);
89 goto err;
90 }
91
92 if (!(flags & PKCS7_NOCERTS)) {
93 for (i = 0; i < sk_X509_num(certs); i++) {
94 if (!PKCS7_add_certificate(p7, sk_X509_value(certs, i)))
95 goto err;
96 }
97 }
98
99 if (flags & PKCS7_DETACHED)
100 PKCS7_set_detached(p7, 1);
101
102 if (flags & (PKCS7_STREAM|PKCS7_PARTIAL))
103 return p7;
104
105 if (PKCS7_final(p7, data, flags))
106 return p7;
107
108 err:
109 PKCS7_free(p7);
110 return NULL;
111 }
112
113 int
PKCS7_final(PKCS7 * p7,BIO * data,int flags)114 PKCS7_final(PKCS7 *p7, BIO *data, int flags)
115 {
116 BIO *p7bio;
117 int ret = 0;
118
119 if (!(p7bio = PKCS7_dataInit(p7, NULL))) {
120 PKCS7error(ERR_R_MALLOC_FAILURE);
121 return 0;
122 }
123
124 SMIME_crlf_copy(data, p7bio, flags);
125
126 (void)BIO_flush(p7bio);
127
128 if (!PKCS7_dataFinal(p7, p7bio)) {
129 PKCS7error(PKCS7_R_PKCS7_DATASIGN);
130 goto err;
131 }
132
133 ret = 1;
134
135 err:
136 BIO_free_all(p7bio);
137
138 return ret;
139 }
140
141 /* Check to see if a cipher exists and if so add S/MIME capabilities */
142
143 static int
add_cipher_smcap(STACK_OF (X509_ALGOR)* sk,int nid,int arg)144 add_cipher_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
145 {
146 if (EVP_get_cipherbynid(nid))
147 return PKCS7_simple_smimecap(sk, nid, arg);
148 return 1;
149 }
150
151 static int
add_digest_smcap(STACK_OF (X509_ALGOR)* sk,int nid,int arg)152 add_digest_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
153 {
154 if (EVP_get_digestbynid(nid))
155 return PKCS7_simple_smimecap(sk, nid, arg);
156 return 1;
157 }
158
159 PKCS7_SIGNER_INFO *
PKCS7_sign_add_signer(PKCS7 * p7,X509 * signcert,EVP_PKEY * pkey,const EVP_MD * md,int flags)160 PKCS7_sign_add_signer(PKCS7 *p7, X509 *signcert, EVP_PKEY *pkey,
161 const EVP_MD *md, int flags)
162 {
163 PKCS7_SIGNER_INFO *si = NULL;
164 STACK_OF(X509_ALGOR) *smcap = NULL;
165
166 if (!X509_check_private_key(signcert, pkey)) {
167 PKCS7error(PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
168 return NULL;
169 }
170
171 if (!(si = PKCS7_add_signature(p7, signcert, pkey, md))) {
172 PKCS7error(PKCS7_R_PKCS7_ADD_SIGNATURE_ERROR);
173 return NULL;
174 }
175
176 if (!(flags & PKCS7_NOCERTS)) {
177 if (!PKCS7_add_certificate(p7, signcert))
178 goto err;
179 }
180
181 if (!(flags & PKCS7_NOATTR)) {
182 if (!PKCS7_add_attrib_content_type(si, NULL))
183 goto err;
184 /* Add SMIMECapabilities */
185 if (!(flags & PKCS7_NOSMIMECAP)) {
186 if (!(smcap = sk_X509_ALGOR_new_null())) {
187 PKCS7error(ERR_R_MALLOC_FAILURE);
188 goto err;
189 }
190 if (!add_cipher_smcap(smcap, NID_aes_256_cbc, -1) ||
191 !add_digest_smcap(smcap, NID_id_GostR3411_94, -1) ||
192 !add_digest_smcap(smcap, NID_id_tc26_gost3411_2012_256, -1) ||
193 !add_digest_smcap(smcap, NID_id_tc26_gost3411_2012_512, -1) ||
194 !add_cipher_smcap(smcap, NID_id_Gost28147_89, -1) ||
195 !add_cipher_smcap(smcap, NID_aes_192_cbc, -1) ||
196 !add_cipher_smcap(smcap, NID_aes_128_cbc, -1) ||
197 !add_cipher_smcap(smcap, NID_des_ede3_cbc, -1) ||
198 !add_cipher_smcap(smcap, NID_rc2_cbc, 128) ||
199 !add_cipher_smcap(smcap, NID_rc2_cbc, 64) ||
200 !add_cipher_smcap(smcap, NID_des_cbc, -1) ||
201 !add_cipher_smcap(smcap, NID_rc2_cbc, 40) ||
202 !PKCS7_add_attrib_smimecap(si, smcap))
203 goto err;
204 sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
205 smcap = NULL;
206 }
207 if (flags & PKCS7_REUSE_DIGEST) {
208 if (!pkcs7_copy_existing_digest(p7, si))
209 goto err;
210 if (!(flags & PKCS7_PARTIAL) &&
211 !PKCS7_SIGNER_INFO_sign(si))
212 goto err;
213 }
214 }
215 return si;
216
217 err:
218 if (smcap)
219 sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
220 return NULL;
221 }
222
223 /* Search for a digest matching SignerInfo digest type and if found
224 * copy across.
225 */
226
227 static int
pkcs7_copy_existing_digest(PKCS7 * p7,PKCS7_SIGNER_INFO * si)228 pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
229 {
230 int i;
231 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
232 PKCS7_SIGNER_INFO *sitmp;
233 ASN1_OCTET_STRING *osdig = NULL;
234
235 sinfos = PKCS7_get_signer_info(p7);
236 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
237 sitmp = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
238 if (si == sitmp)
239 break;
240 if (sk_X509_ATTRIBUTE_num(sitmp->auth_attr) <= 0)
241 continue;
242 if (!OBJ_cmp(si->digest_alg->algorithm,
243 sitmp->digest_alg->algorithm)) {
244 osdig = PKCS7_digest_from_attributes(sitmp->auth_attr);
245 break;
246 }
247
248 }
249
250 if (osdig)
251 return PKCS7_add1_attrib_digest(si, osdig->data, osdig->length);
252
253 PKCS7error(PKCS7_R_NO_MATCHING_DIGEST_TYPE_FOUND);
254 return 0;
255 }
256
257 int
PKCS7_verify(PKCS7 * p7,STACK_OF (X509)* certs,X509_STORE * store,BIO * indata,BIO * out,int flags)258 PKCS7_verify(PKCS7 *p7, STACK_OF(X509) *certs, X509_STORE *store, BIO *indata,
259 BIO *out, int flags)
260 {
261 STACK_OF(X509) *signers;
262 X509 *signer;
263 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
264 PKCS7_SIGNER_INFO *si;
265 X509_STORE_CTX cert_ctx;
266 char buf[4096];
267 int i, j = 0, k, ret = 0;
268 BIO *p7bio;
269 BIO *tmpin, *tmpout;
270
271 if (!p7) {
272 PKCS7error(PKCS7_R_INVALID_NULL_POINTER);
273 return 0;
274 }
275
276 if (!PKCS7_type_is_signed(p7)) {
277 PKCS7error(PKCS7_R_WRONG_CONTENT_TYPE);
278 return 0;
279 }
280
281 /* Check for no data and no content: no data to verify signature */
282 if (PKCS7_get_detached(p7) && !indata) {
283 PKCS7error(PKCS7_R_NO_CONTENT);
284 return 0;
285 }
286
287 /*
288 * Very old Netscape illegally included empty content with
289 * a detached signature. Very old users should upgrade.
290 */
291 /* Check for data and content: two sets of data */
292 if (!PKCS7_get_detached(p7) && indata) {
293 PKCS7error(PKCS7_R_CONTENT_AND_DATA_PRESENT);
294 return 0;
295 }
296
297 sinfos = PKCS7_get_signer_info(p7);
298
299 if (!sinfos || !sk_PKCS7_SIGNER_INFO_num(sinfos)) {
300 PKCS7error(PKCS7_R_NO_SIGNATURES_ON_DATA);
301 return 0;
302 }
303
304
305 signers = PKCS7_get0_signers(p7, certs, flags);
306
307 if (!signers)
308 return 0;
309
310 /* Now verify the certificates */
311
312 if (!(flags & PKCS7_NOVERIFY))
313 for (k = 0; k < sk_X509_num(signers); k++) {
314 signer = sk_X509_value (signers, k);
315 if (!(flags & PKCS7_NOCHAIN)) {
316 if (!X509_STORE_CTX_init(&cert_ctx, store,
317 signer, p7->d.sign->cert)) {
318 PKCS7error(ERR_R_X509_LIB);
319 sk_X509_free(signers);
320 return 0;
321 }
322 if (X509_STORE_CTX_set_default(&cert_ctx,
323 "smime_sign") == 0) {
324 sk_X509_free(signers);
325 return 0;
326 }
327 } else if (!X509_STORE_CTX_init(&cert_ctx, store,
328 signer, NULL)) {
329 PKCS7error(ERR_R_X509_LIB);
330 sk_X509_free(signers);
331 return 0;
332 }
333 if (!(flags & PKCS7_NOCRL))
334 X509_STORE_CTX_set0_crls(&cert_ctx, p7->d.sign->crl);
335 i = X509_verify_cert(&cert_ctx);
336 if (i <= 0)
337 j = X509_STORE_CTX_get_error(&cert_ctx);
338 X509_STORE_CTX_cleanup(&cert_ctx);
339 if (i <= 0) {
340 PKCS7error(PKCS7_R_CERTIFICATE_VERIFY_ERROR);
341 ERR_asprintf_error_data("Verify error:%s",
342 X509_verify_cert_error_string(j));
343 sk_X509_free(signers);
344 return 0;
345 }
346 /* Check for revocation status here */
347 }
348
349 /*
350 * Performance optimization: if the content is a memory BIO then
351 * store its contents in a temporary read only memory BIO. This
352 * avoids potentially large numbers of slow copies of data which will
353 * occur when reading from a read write memory BIO when signatures
354 * are calculated.
355 */
356 if (indata && (BIO_method_type(indata) == BIO_TYPE_MEM)) {
357 char *ptr;
358 long len;
359
360 len = BIO_get_mem_data(indata, &ptr);
361 tmpin = BIO_new_mem_buf(ptr, len);
362 if (tmpin == NULL) {
363 PKCS7error(ERR_R_MALLOC_FAILURE);
364 return 0;
365 }
366 } else
367 tmpin = indata;
368
369
370 if (!(p7bio = PKCS7_dataInit(p7, tmpin)))
371 goto err;
372
373 if (flags & PKCS7_TEXT) {
374 if (!(tmpout = BIO_new(BIO_s_mem()))) {
375 PKCS7error(ERR_R_MALLOC_FAILURE);
376 goto err;
377 }
378 BIO_set_mem_eof_return(tmpout, 0);
379 } else
380 tmpout = out;
381
382 /* We now have to 'read' from p7bio to calculate digests etc. */
383 for (;;) {
384 i = BIO_read(p7bio, buf, sizeof(buf));
385 if (i <= 0)
386 break;
387 if (tmpout)
388 BIO_write(tmpout, buf, i);
389 }
390
391 if (flags & PKCS7_TEXT) {
392 if (!SMIME_text(tmpout, out)) {
393 PKCS7error(PKCS7_R_SMIME_TEXT_ERROR);
394 BIO_free(tmpout);
395 goto err;
396 }
397 BIO_free(tmpout);
398 }
399
400 /* Now Verify All Signatures */
401 if (!(flags & PKCS7_NOSIGS))
402 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
403 si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
404 signer = sk_X509_value (signers, i);
405 j = PKCS7_signatureVerify(p7bio, p7, si, signer);
406 if (j <= 0) {
407 PKCS7error(PKCS7_R_SIGNATURE_FAILURE);
408 goto err;
409 }
410 }
411
412 ret = 1;
413
414 err:
415 if (tmpin == indata) {
416 if (indata)
417 BIO_pop(p7bio);
418 }
419 BIO_free_all(p7bio);
420 sk_X509_free(signers);
421
422 return ret;
423 }
424
STACK_OF(X509)425 STACK_OF(X509) *
426 PKCS7_get0_signers(PKCS7 *p7, STACK_OF(X509) *certs, int flags)
427 {
428 STACK_OF(X509) *signers;
429 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
430 PKCS7_SIGNER_INFO *si;
431 PKCS7_ISSUER_AND_SERIAL *ias;
432 X509 *signer;
433 int i;
434
435 if (!p7) {
436 PKCS7error(PKCS7_R_INVALID_NULL_POINTER);
437 return NULL;
438 }
439
440 if (!PKCS7_type_is_signed(p7)) {
441 PKCS7error(PKCS7_R_WRONG_CONTENT_TYPE);
442 return NULL;
443 }
444
445 /* Collect all the signers together */
446 sinfos = PKCS7_get_signer_info(p7);
447 if (sk_PKCS7_SIGNER_INFO_num(sinfos) <= 0) {
448 PKCS7error(PKCS7_R_NO_SIGNERS);
449 return 0;
450 }
451
452 if (!(signers = sk_X509_new_null())) {
453 PKCS7error(ERR_R_MALLOC_FAILURE);
454 return NULL;
455 }
456
457 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
458 si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
459 ias = si->issuer_and_serial;
460 signer = NULL;
461 /* If any certificates passed they take priority */
462 if (certs)
463 signer = X509_find_by_issuer_and_serial (certs,
464 ias->issuer, ias->serial);
465 if (!signer && !(flags & PKCS7_NOINTERN) && p7->d.sign->cert)
466 signer =
467 X509_find_by_issuer_and_serial(p7->d.sign->cert,
468 ias->issuer, ias->serial);
469 if (!signer) {
470 PKCS7error(PKCS7_R_SIGNER_CERTIFICATE_NOT_FOUND);
471 sk_X509_free(signers);
472 return 0;
473 }
474
475 if (!sk_X509_push(signers, signer)) {
476 sk_X509_free(signers);
477 return NULL;
478 }
479 }
480 return signers;
481 }
482
483 /* Build a complete PKCS#7 enveloped data */
484
485 PKCS7 *
PKCS7_encrypt(STACK_OF (X509)* certs,BIO * in,const EVP_CIPHER * cipher,int flags)486 PKCS7_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher,
487 int flags)
488 {
489 PKCS7 *p7;
490 BIO *p7bio = NULL;
491 int i;
492 X509 *x509;
493
494 if (!(p7 = PKCS7_new())) {
495 PKCS7error(ERR_R_MALLOC_FAILURE);
496 return NULL;
497 }
498
499 if (!PKCS7_set_type(p7, NID_pkcs7_enveloped))
500 goto err;
501 if (!PKCS7_set_cipher(p7, cipher)) {
502 PKCS7error(PKCS7_R_ERROR_SETTING_CIPHER);
503 goto err;
504 }
505
506 for (i = 0; i < sk_X509_num(certs); i++) {
507 x509 = sk_X509_value(certs, i);
508 if (!PKCS7_add_recipient(p7, x509)) {
509 PKCS7error(PKCS7_R_ERROR_ADDING_RECIPIENT);
510 goto err;
511 }
512 }
513
514 if (flags & PKCS7_STREAM)
515 return p7;
516
517 if (PKCS7_final(p7, in, flags))
518 return p7;
519
520 err:
521 BIO_free_all(p7bio);
522 PKCS7_free(p7);
523 return NULL;
524 }
525
526 int
PKCS7_decrypt(PKCS7 * p7,EVP_PKEY * pkey,X509 * cert,BIO * data,int flags)527 PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
528 {
529 BIO *tmpmem;
530 int ret, i;
531 char buf[4096];
532
533 if (!p7) {
534 PKCS7error(PKCS7_R_INVALID_NULL_POINTER);
535 return 0;
536 }
537
538 if (!PKCS7_type_is_enveloped(p7)) {
539 PKCS7error(PKCS7_R_WRONG_CONTENT_TYPE);
540 return 0;
541 }
542
543 if (cert && !X509_check_private_key(cert, pkey)) {
544 PKCS7error(PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
545 return 0;
546 }
547
548 if (!(tmpmem = PKCS7_dataDecode(p7, pkey, NULL, cert))) {
549 PKCS7error(PKCS7_R_DECRYPT_ERROR);
550 return 0;
551 }
552
553 if (flags & PKCS7_TEXT) {
554 BIO *tmpbuf;
555
556 /* Encrypt BIOs can't do BIO_gets() so add a buffer BIO */
557 if (!(tmpbuf = BIO_new(BIO_f_buffer()))) {
558 PKCS7error(ERR_R_MALLOC_FAILURE);
559 BIO_free_all(tmpmem);
560 return 0;
561 }
562 BIO_push(tmpbuf, tmpmem);
563 ret = SMIME_text(tmpbuf, data);
564 if (ret > 0 && BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
565 if (!BIO_get_cipher_status(tmpmem))
566 ret = 0;
567 }
568 BIO_free_all(tmpbuf);
569 return ret;
570 } else {
571 for (;;) {
572 i = BIO_read(tmpmem, buf, sizeof(buf));
573 if (i <= 0) {
574 ret = 1;
575 if (BIO_method_type(tmpmem) ==
576 BIO_TYPE_CIPHER) {
577 if (!BIO_get_cipher_status(tmpmem))
578 ret = 0;
579 }
580 break;
581 }
582 if (BIO_write(data, buf, i) != i) {
583 ret = 0;
584 break;
585 }
586 }
587 BIO_free_all(tmpmem);
588 return ret;
589 }
590 }
591