1 /*
2 * Copyright 1999-2020 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (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 /* Simple PKCS#7 processing functions */
11
12 #include <stdio.h>
13 #include "internal/cryptlib.h"
14 #include <openssl/x509.h>
15 #include <openssl/x509v3.h>
16
17
18 #define BUFFERSIZE 4096
19
20 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si);
21
PKCS7_sign(X509 * signcert,EVP_PKEY * pkey,STACK_OF (X509)* certs,BIO * data,int flags)22 PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
23 BIO *data, int flags)
24 {
25 PKCS7 *p7;
26 int i;
27
28 if ((p7 = PKCS7_new()) == NULL) {
29 PKCS7err(PKCS7_F_PKCS7_SIGN, ERR_R_MALLOC_FAILURE);
30 return NULL;
31 }
32
33 if (!PKCS7_set_type(p7, NID_pkcs7_signed))
34 goto err;
35
36 if (!PKCS7_content_new(p7, NID_pkcs7_data))
37 goto err;
38
39 if (pkey && !PKCS7_sign_add_signer(p7, signcert, pkey, NULL, flags)) {
40 PKCS7err(PKCS7_F_PKCS7_SIGN, PKCS7_R_PKCS7_ADD_SIGNER_ERROR);
41 goto err;
42 }
43
44 if (!(flags & PKCS7_NOCERTS)) {
45 for (i = 0; i < sk_X509_num(certs); i++) {
46 if (!PKCS7_add_certificate(p7, sk_X509_value(certs, i)))
47 goto err;
48 }
49 }
50
51 if (flags & PKCS7_DETACHED)
52 PKCS7_set_detached(p7, 1);
53
54 if (flags & (PKCS7_STREAM | PKCS7_PARTIAL))
55 return p7;
56
57 if (PKCS7_final(p7, data, flags))
58 return p7;
59
60 err:
61 PKCS7_free(p7);
62 return NULL;
63 }
64
PKCS7_final(PKCS7 * p7,BIO * data,int flags)65 int PKCS7_final(PKCS7 *p7, BIO *data, int flags)
66 {
67 BIO *p7bio;
68 int ret = 0;
69
70 if ((p7bio = PKCS7_dataInit(p7, NULL)) == NULL) {
71 PKCS7err(PKCS7_F_PKCS7_FINAL, ERR_R_MALLOC_FAILURE);
72 return 0;
73 }
74
75 SMIME_crlf_copy(data, p7bio, flags);
76
77 (void)BIO_flush(p7bio);
78
79 if (!PKCS7_dataFinal(p7, p7bio)) {
80 PKCS7err(PKCS7_F_PKCS7_FINAL, PKCS7_R_PKCS7_DATASIGN);
81 goto err;
82 }
83
84 ret = 1;
85
86 err:
87 BIO_free_all(p7bio);
88
89 return ret;
90
91 }
92
93 /* Check to see if a cipher exists and if so add S/MIME capabilities */
94
add_cipher_smcap(STACK_OF (X509_ALGOR)* sk,int nid,int arg)95 static int add_cipher_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
96 {
97 if (EVP_get_cipherbynid(nid))
98 return PKCS7_simple_smimecap(sk, nid, arg);
99 return 1;
100 }
101
add_digest_smcap(STACK_OF (X509_ALGOR)* sk,int nid,int arg)102 static int add_digest_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
103 {
104 if (EVP_get_digestbynid(nid))
105 return PKCS7_simple_smimecap(sk, nid, arg);
106 return 1;
107 }
108
PKCS7_sign_add_signer(PKCS7 * p7,X509 * signcert,EVP_PKEY * pkey,const EVP_MD * md,int flags)109 PKCS7_SIGNER_INFO *PKCS7_sign_add_signer(PKCS7 *p7, X509 *signcert,
110 EVP_PKEY *pkey, const EVP_MD *md,
111 int flags)
112 {
113 PKCS7_SIGNER_INFO *si = NULL;
114 STACK_OF(X509_ALGOR) *smcap = NULL;
115 if (!X509_check_private_key(signcert, pkey)) {
116 PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
117 PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
118 return NULL;
119 }
120
121 if ((si = PKCS7_add_signature(p7, signcert, pkey, md)) == NULL) {
122 PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
123 PKCS7_R_PKCS7_ADD_SIGNATURE_ERROR);
124 return NULL;
125 }
126
127 if (!(flags & PKCS7_NOCERTS)) {
128 if (!PKCS7_add_certificate(p7, signcert))
129 goto err;
130 }
131
132 if (!(flags & PKCS7_NOATTR)) {
133 if (!PKCS7_add_attrib_content_type(si, NULL))
134 goto err;
135 /* Add SMIMECapabilities */
136 if (!(flags & PKCS7_NOSMIMECAP)) {
137 if ((smcap = sk_X509_ALGOR_new_null()) == NULL) {
138 PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER, ERR_R_MALLOC_FAILURE);
139 goto err;
140 }
141 if (!add_cipher_smcap(smcap, NID_aes_256_cbc, -1)
142 || !add_digest_smcap(smcap, NID_id_GostR3411_2012_256, -1)
143 || !add_digest_smcap(smcap, NID_id_GostR3411_2012_512, -1)
144 || !add_digest_smcap(smcap, NID_id_GostR3411_94, -1)
145 || !add_cipher_smcap(smcap, NID_id_Gost28147_89, -1)
146 || !add_cipher_smcap(smcap, NID_aes_192_cbc, -1)
147 || !add_cipher_smcap(smcap, NID_aes_128_cbc, -1)
148 || !add_cipher_smcap(smcap, NID_des_ede3_cbc, -1)
149 || !add_cipher_smcap(smcap, NID_rc2_cbc, 128)
150 || !add_cipher_smcap(smcap, NID_rc2_cbc, 64)
151 || !add_cipher_smcap(smcap, NID_des_cbc, -1)
152 || !add_cipher_smcap(smcap, NID_rc2_cbc, 40)
153 || !PKCS7_add_attrib_smimecap(si, smcap))
154 goto err;
155 sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
156 smcap = NULL;
157 }
158 if (flags & PKCS7_REUSE_DIGEST) {
159 if (!pkcs7_copy_existing_digest(p7, si))
160 goto err;
161 if (!(flags & PKCS7_PARTIAL) && !PKCS7_SIGNER_INFO_sign(si))
162 goto err;
163 }
164 }
165 return si;
166 err:
167 sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
168 return NULL;
169 }
170
171 /*
172 * Search for a digest matching SignerInfo digest type and if found copy
173 * across.
174 */
175
pkcs7_copy_existing_digest(PKCS7 * p7,PKCS7_SIGNER_INFO * si)176 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
177 {
178 int i;
179 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
180 PKCS7_SIGNER_INFO *sitmp;
181 ASN1_OCTET_STRING *osdig = NULL;
182 sinfos = PKCS7_get_signer_info(p7);
183 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
184 sitmp = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
185 if (si == sitmp)
186 break;
187 if (sk_X509_ATTRIBUTE_num(sitmp->auth_attr) <= 0)
188 continue;
189 if (!OBJ_cmp(si->digest_alg->algorithm, sitmp->digest_alg->algorithm)) {
190 osdig = PKCS7_digest_from_attributes(sitmp->auth_attr);
191 break;
192 }
193
194 }
195
196 if (osdig)
197 return PKCS7_add1_attrib_digest(si, osdig->data, osdig->length);
198
199 PKCS7err(PKCS7_F_PKCS7_COPY_EXISTING_DIGEST,
200 PKCS7_R_NO_MATCHING_DIGEST_TYPE_FOUND);
201 return 0;
202 }
203
PKCS7_verify(PKCS7 * p7,STACK_OF (X509)* certs,X509_STORE * store,BIO * indata,BIO * out,int flags)204 int PKCS7_verify(PKCS7 *p7, STACK_OF(X509) *certs, X509_STORE *store,
205 BIO *indata, BIO *out, int flags)
206 {
207 STACK_OF(X509) *signers;
208 X509 *signer;
209 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
210 PKCS7_SIGNER_INFO *si;
211 X509_STORE_CTX *cert_ctx = NULL;
212 char *buf = NULL;
213 int i, j = 0, k, ret = 0;
214 BIO *p7bio = NULL;
215 BIO *tmpin = NULL, *tmpout = NULL;
216
217 if (!p7) {
218 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_INVALID_NULL_POINTER);
219 return 0;
220 }
221
222 if (!PKCS7_type_is_signed(p7)) {
223 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_WRONG_CONTENT_TYPE);
224 return 0;
225 }
226
227 /* Check for no data and no content: no data to verify signature */
228 if (PKCS7_get_detached(p7) && !indata) {
229 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_CONTENT);
230 return 0;
231 }
232
233 if (flags & PKCS7_NO_DUAL_CONTENT) {
234 /*
235 * This was originally "#if 0" because we thought that only old broken
236 * Netscape did this. It turns out that Authenticode uses this kind
237 * of "extended" PKCS7 format, and things like UEFI secure boot and
238 * tools like osslsigncode need it. In Authenticode the verification
239 * process is different, but the existing PKCs7 verification works.
240 */
241 if (!PKCS7_get_detached(p7) && indata) {
242 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_CONTENT_AND_DATA_PRESENT);
243 return 0;
244 }
245 }
246
247 sinfos = PKCS7_get_signer_info(p7);
248
249 if (!sinfos || !sk_PKCS7_SIGNER_INFO_num(sinfos)) {
250 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_SIGNATURES_ON_DATA);
251 return 0;
252 }
253
254 signers = PKCS7_get0_signers(p7, certs, flags);
255 if (!signers)
256 return 0;
257
258 /* Now verify the certificates */
259
260 cert_ctx = X509_STORE_CTX_new();
261 if (cert_ctx == NULL)
262 goto err;
263 if (!(flags & PKCS7_NOVERIFY))
264 for (k = 0; k < sk_X509_num(signers); k++) {
265 signer = sk_X509_value(signers, k);
266 if (!(flags & PKCS7_NOCHAIN)) {
267 if (!X509_STORE_CTX_init(cert_ctx, store, signer,
268 p7->d.sign->cert)) {
269 PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
270 goto err;
271 }
272 X509_STORE_CTX_set_default(cert_ctx, "smime_sign");
273 } else if (!X509_STORE_CTX_init(cert_ctx, store, signer, NULL)) {
274 PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
275 goto err;
276 }
277 if (!(flags & PKCS7_NOCRL))
278 X509_STORE_CTX_set0_crls(cert_ctx, p7->d.sign->crl);
279 i = X509_verify_cert(cert_ctx);
280 if (i <= 0)
281 j = X509_STORE_CTX_get_error(cert_ctx);
282 X509_STORE_CTX_cleanup(cert_ctx);
283 if (i <= 0) {
284 PKCS7err(PKCS7_F_PKCS7_VERIFY,
285 PKCS7_R_CERTIFICATE_VERIFY_ERROR);
286 ERR_add_error_data(2, "Verify error:",
287 X509_verify_cert_error_string(j));
288 goto err;
289 }
290 /* Check for revocation status here */
291 }
292
293 /*
294 * Performance optimization: if the content is a memory BIO then store
295 * its contents in a temporary read only memory BIO. This avoids
296 * potentially large numbers of slow copies of data which will occur when
297 * reading from a read write memory BIO when signatures are calculated.
298 */
299
300 if (indata && (BIO_method_type(indata) == BIO_TYPE_MEM)) {
301 char *ptr;
302 long len;
303 len = BIO_get_mem_data(indata, &ptr);
304 tmpin = (len == 0) ? indata : BIO_new_mem_buf(ptr, len);
305 if (tmpin == NULL) {
306 PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
307 goto err;
308 }
309 } else
310 tmpin = indata;
311
312 if ((p7bio = PKCS7_dataInit(p7, tmpin)) == NULL)
313 goto err;
314
315 if (flags & PKCS7_TEXT) {
316 if ((tmpout = BIO_new(BIO_s_mem())) == NULL) {
317 PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
318 goto err;
319 }
320 BIO_set_mem_eof_return(tmpout, 0);
321 } else
322 tmpout = out;
323
324 /* We now have to 'read' from p7bio to calculate digests etc. */
325 if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
326 PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
327 goto err;
328 }
329 for (;;) {
330 i = BIO_read(p7bio, buf, BUFFERSIZE);
331 if (i <= 0)
332 break;
333 if (tmpout)
334 BIO_write(tmpout, buf, i);
335 }
336
337 if (flags & PKCS7_TEXT) {
338 if (!SMIME_text(tmpout, out)) {
339 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SMIME_TEXT_ERROR);
340 BIO_free(tmpout);
341 goto err;
342 }
343 BIO_free(tmpout);
344 }
345
346 /* Now Verify All Signatures */
347 if (!(flags & PKCS7_NOSIGS))
348 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
349 si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
350 signer = sk_X509_value(signers, i);
351 j = PKCS7_signatureVerify(p7bio, p7, si, signer);
352 if (j <= 0) {
353 PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SIGNATURE_FAILURE);
354 goto err;
355 }
356 }
357
358 ret = 1;
359
360 err:
361 X509_STORE_CTX_free(cert_ctx);
362 OPENSSL_free(buf);
363 if (tmpin == indata) {
364 if (indata)
365 BIO_pop(p7bio);
366 }
367 BIO_free_all(p7bio);
368 sk_X509_free(signers);
369 return ret;
370 }
371
STACK_OF(X509)372 STACK_OF(X509) *PKCS7_get0_signers(PKCS7 *p7, STACK_OF(X509) *certs,
373 int flags)
374 {
375 STACK_OF(X509) *signers;
376 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
377 PKCS7_SIGNER_INFO *si;
378 PKCS7_ISSUER_AND_SERIAL *ias;
379 X509 *signer;
380 int i;
381
382 if (!p7) {
383 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_INVALID_NULL_POINTER);
384 return NULL;
385 }
386
387 if (!PKCS7_type_is_signed(p7)) {
388 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_WRONG_CONTENT_TYPE);
389 return NULL;
390 }
391
392 /* Collect all the signers together */
393
394 sinfos = PKCS7_get_signer_info(p7);
395
396 if (sk_PKCS7_SIGNER_INFO_num(sinfos) <= 0) {
397 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_NO_SIGNERS);
398 return 0;
399 }
400
401 if ((signers = sk_X509_new_null()) == NULL) {
402 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, ERR_R_MALLOC_FAILURE);
403 return NULL;
404 }
405
406 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
407 si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
408 ias = si->issuer_and_serial;
409 signer = NULL;
410 /* If any certificates passed they take priority */
411 if (certs)
412 signer = X509_find_by_issuer_and_serial(certs,
413 ias->issuer, ias->serial);
414 if (!signer && !(flags & PKCS7_NOINTERN)
415 && p7->d.sign->cert)
416 signer =
417 X509_find_by_issuer_and_serial(p7->d.sign->cert,
418 ias->issuer, ias->serial);
419 if (!signer) {
420 PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,
421 PKCS7_R_SIGNER_CERTIFICATE_NOT_FOUND);
422 sk_X509_free(signers);
423 return 0;
424 }
425
426 if (!sk_X509_push(signers, signer)) {
427 sk_X509_free(signers);
428 return NULL;
429 }
430 }
431 return signers;
432 }
433
434 /* Build a complete PKCS#7 enveloped data */
435
PKCS7_encrypt(STACK_OF (X509)* certs,BIO * in,const EVP_CIPHER * cipher,int flags)436 PKCS7 *PKCS7_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher,
437 int flags)
438 {
439 PKCS7 *p7;
440 BIO *p7bio = NULL;
441 int i;
442 X509 *x509;
443 if ((p7 = PKCS7_new()) == NULL) {
444 PKCS7err(PKCS7_F_PKCS7_ENCRYPT, ERR_R_MALLOC_FAILURE);
445 return NULL;
446 }
447
448 if (!PKCS7_set_type(p7, NID_pkcs7_enveloped))
449 goto err;
450 if (!PKCS7_set_cipher(p7, cipher)) {
451 PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_SETTING_CIPHER);
452 goto err;
453 }
454
455 for (i = 0; i < sk_X509_num(certs); i++) {
456 x509 = sk_X509_value(certs, i);
457 if (!PKCS7_add_recipient(p7, x509)) {
458 PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_ADDING_RECIPIENT);
459 goto err;
460 }
461 }
462
463 if (flags & PKCS7_STREAM)
464 return p7;
465
466 if (PKCS7_final(p7, in, flags))
467 return p7;
468
469 err:
470
471 BIO_free_all(p7bio);
472 PKCS7_free(p7);
473 return NULL;
474
475 }
476
PKCS7_decrypt(PKCS7 * p7,EVP_PKEY * pkey,X509 * cert,BIO * data,int flags)477 int PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
478 {
479 BIO *tmpmem;
480 int ret = 0, i;
481 char *buf = NULL;
482
483 if (!p7) {
484 PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_INVALID_NULL_POINTER);
485 return 0;
486 }
487
488 if (!PKCS7_type_is_enveloped(p7)) {
489 PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_WRONG_CONTENT_TYPE);
490 return 0;
491 }
492
493 if (cert && !X509_check_private_key(cert, pkey)) {
494 PKCS7err(PKCS7_F_PKCS7_DECRYPT,
495 PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
496 return 0;
497 }
498
499 if ((tmpmem = PKCS7_dataDecode(p7, pkey, NULL, cert)) == NULL) {
500 PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_DECRYPT_ERROR);
501 return 0;
502 }
503
504 if (flags & PKCS7_TEXT) {
505 BIO *tmpbuf, *bread;
506 /* Encrypt BIOs can't do BIO_gets() so add a buffer BIO */
507 if ((tmpbuf = BIO_new(BIO_f_buffer())) == NULL) {
508 PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
509 BIO_free_all(tmpmem);
510 return 0;
511 }
512 if ((bread = BIO_push(tmpbuf, tmpmem)) == NULL) {
513 PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
514 BIO_free_all(tmpbuf);
515 BIO_free_all(tmpmem);
516 return 0;
517 }
518 ret = SMIME_text(bread, data);
519 if (ret > 0 && BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
520 if (!BIO_get_cipher_status(tmpmem))
521 ret = 0;
522 }
523 BIO_free_all(bread);
524 return ret;
525 }
526 if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
527 PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
528 goto err;
529 }
530 for (;;) {
531 i = BIO_read(tmpmem, buf, BUFFERSIZE);
532 if (i <= 0) {
533 ret = 1;
534 if (BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
535 if (!BIO_get_cipher_status(tmpmem))
536 ret = 0;
537 }
538
539 break;
540 }
541 if (BIO_write(data, buf, i) != i) {
542 break;
543 }
544 }
545 err:
546 OPENSSL_free(buf);
547 BIO_free_all(tmpmem);
548 return ret;
549 }
550