1 /*
2 * Copyright 1999-2021 The OpenSSL Project Authors. All Rights Reserved.
3 *
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
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 #include "pk7_local.h"
17
18 #define BUFFERSIZE 4096
19
20
21 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si);
22
PKCS7_sign_ex(X509 * signcert,EVP_PKEY * pkey,STACK_OF (X509)* certs,BIO * data,int flags,OSSL_LIB_CTX * libctx,const char * propq)23 PKCS7 *PKCS7_sign_ex(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
24 BIO *data, int flags, OSSL_LIB_CTX *libctx,
25 const char *propq)
26 {
27 PKCS7 *p7;
28 int i;
29
30 if ((p7 = PKCS7_new_ex(libctx, propq)) == NULL) {
31 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
32 return NULL;
33 }
34
35 if (!PKCS7_set_type(p7, NID_pkcs7_signed))
36 goto err;
37
38 if (!PKCS7_content_new(p7, NID_pkcs7_data))
39 goto err;
40
41 if (pkey && !PKCS7_sign_add_signer(p7, signcert, pkey, NULL, flags)) {
42 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_PKCS7_ADD_SIGNER_ERROR);
43 goto err;
44 }
45
46 if (!(flags & PKCS7_NOCERTS)) {
47 for (i = 0; i < sk_X509_num(certs); i++) {
48 if (!PKCS7_add_certificate(p7, sk_X509_value(certs, i)))
49 goto err;
50 }
51 }
52
53 if (flags & PKCS7_DETACHED)
54 PKCS7_set_detached(p7, 1);
55
56 if (flags & (PKCS7_STREAM | PKCS7_PARTIAL))
57 return p7;
58
59 if (PKCS7_final(p7, data, flags))
60 return p7;
61
62 err:
63 PKCS7_free(p7);
64 return NULL;
65 }
66
PKCS7_sign(X509 * signcert,EVP_PKEY * pkey,STACK_OF (X509)* certs,BIO * data,int flags)67 PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
68 BIO *data, int flags)
69 {
70 return PKCS7_sign_ex(signcert, pkey, certs, data, flags, NULL, NULL);
71 }
72
73
PKCS7_final(PKCS7 * p7,BIO * data,int flags)74 int PKCS7_final(PKCS7 *p7, BIO *data, int flags)
75 {
76 BIO *p7bio;
77 int ret = 0;
78
79 if ((p7bio = PKCS7_dataInit(p7, NULL)) == NULL) {
80 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
81 return 0;
82 }
83
84 if (!SMIME_crlf_copy(data, p7bio, flags))
85 goto err;
86
87 (void)BIO_flush(p7bio);
88
89 if (!PKCS7_dataFinal(p7, p7bio)) {
90 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_PKCS7_DATASIGN);
91 goto err;
92 }
93 ret = 1;
94 err:
95 BIO_free_all(p7bio);
96
97 return ret;
98
99 }
100
101 /* Check to see if a cipher exists and if so add S/MIME capabilities */
102
add_cipher_smcap(STACK_OF (X509_ALGOR)* sk,int nid,int arg)103 static int add_cipher_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
104 {
105 if (EVP_get_cipherbynid(nid))
106 return PKCS7_simple_smimecap(sk, nid, arg);
107 return 1;
108 }
109
add_digest_smcap(STACK_OF (X509_ALGOR)* sk,int nid,int arg)110 static int add_digest_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
111 {
112 if (EVP_get_digestbynid(nid))
113 return PKCS7_simple_smimecap(sk, nid, arg);
114 return 1;
115 }
116
PKCS7_sign_add_signer(PKCS7 * p7,X509 * signcert,EVP_PKEY * pkey,const EVP_MD * md,int flags)117 PKCS7_SIGNER_INFO *PKCS7_sign_add_signer(PKCS7 *p7, X509 *signcert,
118 EVP_PKEY *pkey, const EVP_MD *md,
119 int flags)
120 {
121 PKCS7_SIGNER_INFO *si = NULL;
122 STACK_OF(X509_ALGOR) *smcap = NULL;
123
124 if (!X509_check_private_key(signcert, pkey)) {
125 ERR_raise(ERR_LIB_PKCS7,
126 PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
127 return NULL;
128 }
129
130 if ((si = PKCS7_add_signature(p7, signcert, pkey, md)) == NULL) {
131 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_PKCS7_ADD_SIGNATURE_ERROR);
132 return NULL;
133 }
134
135 si->ctx = ossl_pkcs7_get0_ctx(p7);
136 if (!(flags & PKCS7_NOCERTS)) {
137 if (!PKCS7_add_certificate(p7, signcert))
138 goto err;
139 }
140
141 if (!(flags & PKCS7_NOATTR)) {
142 if (!PKCS7_add_attrib_content_type(si, NULL))
143 goto err;
144 /* Add SMIMECapabilities */
145 if (!(flags & PKCS7_NOSMIMECAP)) {
146 if ((smcap = sk_X509_ALGOR_new_null()) == NULL) {
147 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
148 goto err;
149 }
150 if (!add_cipher_smcap(smcap, NID_aes_256_cbc, -1)
151 || !add_digest_smcap(smcap, NID_id_GostR3411_2012_256, -1)
152 || !add_digest_smcap(smcap, NID_id_GostR3411_2012_512, -1)
153 || !add_digest_smcap(smcap, NID_id_GostR3411_94, -1)
154 || !add_cipher_smcap(smcap, NID_id_Gost28147_89, -1)
155 || !add_cipher_smcap(smcap, NID_aes_192_cbc, -1)
156 || !add_cipher_smcap(smcap, NID_aes_128_cbc, -1)
157 || !add_cipher_smcap(smcap, NID_des_ede3_cbc, -1)
158 || !add_cipher_smcap(smcap, NID_rc2_cbc, 128)
159 || !add_cipher_smcap(smcap, NID_rc2_cbc, 64)
160 || !add_cipher_smcap(smcap, NID_des_cbc, -1)
161 || !add_cipher_smcap(smcap, NID_rc2_cbc, 40)
162 || !PKCS7_add_attrib_smimecap(si, smcap))
163 goto err;
164 sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
165 smcap = NULL;
166 }
167 if (flags & PKCS7_REUSE_DIGEST) {
168 if (!pkcs7_copy_existing_digest(p7, si))
169 goto err;
170 if (!(flags & PKCS7_PARTIAL)
171 && !PKCS7_SIGNER_INFO_sign(si))
172 goto err;
173 }
174 }
175 return si;
176 err:
177 sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
178 return NULL;
179 }
180
181 /*
182 * Search for a digest matching SignerInfo digest type and if found copy
183 * across.
184 */
185
pkcs7_copy_existing_digest(PKCS7 * p7,PKCS7_SIGNER_INFO * si)186 static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
187 {
188 int i;
189 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
190 PKCS7_SIGNER_INFO *sitmp;
191 ASN1_OCTET_STRING *osdig = NULL;
192 sinfos = PKCS7_get_signer_info(p7);
193 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
194 sitmp = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
195 if (si == sitmp)
196 break;
197 if (sk_X509_ATTRIBUTE_num(sitmp->auth_attr) <= 0)
198 continue;
199 if (!OBJ_cmp(si->digest_alg->algorithm, sitmp->digest_alg->algorithm)) {
200 osdig = PKCS7_digest_from_attributes(sitmp->auth_attr);
201 break;
202 }
203
204 }
205
206 if (osdig != NULL)
207 return PKCS7_add1_attrib_digest(si, osdig->data, osdig->length);
208
209 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_NO_MATCHING_DIGEST_TYPE_FOUND);
210 return 0;
211 }
212
PKCS7_verify(PKCS7 * p7,STACK_OF (X509)* certs,X509_STORE * store,BIO * indata,BIO * out,int flags)213 int PKCS7_verify(PKCS7 *p7, STACK_OF(X509) *certs, X509_STORE *store,
214 BIO *indata, BIO *out, int flags)
215 {
216 STACK_OF(X509) *signers;
217 X509 *signer;
218 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
219 PKCS7_SIGNER_INFO *si;
220 X509_STORE_CTX *cert_ctx = NULL;
221 char *buf = NULL;
222 int i, j = 0, k, ret = 0;
223 BIO *p7bio = NULL;
224 BIO *tmpout = NULL;
225 const PKCS7_CTX *p7_ctx;
226
227 if (p7 == NULL) {
228 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_INVALID_NULL_POINTER);
229 return 0;
230 }
231
232 if (!PKCS7_type_is_signed(p7)) {
233 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
234 return 0;
235 }
236
237 /* Check for no data and no content: no data to verify signature */
238 if (PKCS7_get_detached(p7) && !indata) {
239 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_NO_CONTENT);
240 return 0;
241 }
242
243 if (flags & PKCS7_NO_DUAL_CONTENT) {
244 /*
245 * This was originally "#if 0" because we thought that only old broken
246 * Netscape did this. It turns out that Authenticode uses this kind
247 * of "extended" PKCS7 format, and things like UEFI secure boot and
248 * tools like osslsigncode need it. In Authenticode the verification
249 * process is different, but the existing PKCs7 verification works.
250 */
251 if (!PKCS7_get_detached(p7) && indata) {
252 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_CONTENT_AND_DATA_PRESENT);
253 return 0;
254 }
255 }
256
257 sinfos = PKCS7_get_signer_info(p7);
258
259 if (!sinfos || !sk_PKCS7_SIGNER_INFO_num(sinfos)) {
260 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_NO_SIGNATURES_ON_DATA);
261 return 0;
262 }
263
264 signers = PKCS7_get0_signers(p7, certs, flags);
265 if (signers == NULL)
266 return 0;
267
268 /* Now verify the certificates */
269 p7_ctx = ossl_pkcs7_get0_ctx(p7);
270 cert_ctx = X509_STORE_CTX_new_ex(ossl_pkcs7_ctx_get0_libctx(p7_ctx),
271 ossl_pkcs7_ctx_get0_propq(p7_ctx));
272 if (cert_ctx == NULL)
273 goto err;
274 if (!(flags & PKCS7_NOVERIFY))
275 for (k = 0; k < sk_X509_num(signers); k++) {
276 signer = sk_X509_value(signers, k);
277 if (!(flags & PKCS7_NOCHAIN)) {
278 if (!X509_STORE_CTX_init(cert_ctx, store, signer,
279 p7->d.sign->cert)) {
280 ERR_raise(ERR_LIB_PKCS7, ERR_R_X509_LIB);
281 goto err;
282 }
283 X509_STORE_CTX_set_default(cert_ctx, "smime_sign");
284 } else if (!X509_STORE_CTX_init(cert_ctx, store, signer, NULL)) {
285 ERR_raise(ERR_LIB_PKCS7, ERR_R_X509_LIB);
286 goto err;
287 }
288 if (!(flags & PKCS7_NOCRL))
289 X509_STORE_CTX_set0_crls(cert_ctx, p7->d.sign->crl);
290 i = X509_verify_cert(cert_ctx);
291 if (i <= 0)
292 j = X509_STORE_CTX_get_error(cert_ctx);
293 if (i <= 0) {
294 ERR_raise_data(ERR_LIB_PKCS7, PKCS7_R_CERTIFICATE_VERIFY_ERROR,
295 "Verify error: %s",
296 X509_verify_cert_error_string(j));
297 goto err;
298 }
299 /* Check for revocation status here */
300 }
301
302 if ((p7bio = PKCS7_dataInit(p7, indata)) == NULL)
303 goto err;
304
305 if (flags & PKCS7_TEXT) {
306 if ((tmpout = BIO_new(BIO_s_mem())) == NULL) {
307 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
308 goto err;
309 }
310 BIO_set_mem_eof_return(tmpout, 0);
311 } else
312 tmpout = out;
313
314 /* We now have to 'read' from p7bio to calculate digests etc. */
315 if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
316 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
317 goto err;
318 }
319 for (;;) {
320 i = BIO_read(p7bio, buf, BUFFERSIZE);
321 if (i <= 0)
322 break;
323 if (tmpout)
324 BIO_write(tmpout, buf, i);
325 }
326
327 if (flags & PKCS7_TEXT) {
328 if (!SMIME_text(tmpout, out)) {
329 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_SMIME_TEXT_ERROR);
330 BIO_free(tmpout);
331 goto err;
332 }
333 BIO_free(tmpout);
334 }
335
336 /* Now Verify All Signatures */
337 if (!(flags & PKCS7_NOSIGS))
338 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
339 si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
340 signer = sk_X509_value(signers, i);
341 j = PKCS7_signatureVerify(p7bio, p7, si, signer);
342 if (j <= 0) {
343 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_SIGNATURE_FAILURE);
344 goto err;
345 }
346 }
347
348 ret = 1;
349
350 err:
351 X509_STORE_CTX_free(cert_ctx);
352 OPENSSL_free(buf);
353 if (indata)
354 BIO_pop(p7bio);
355 BIO_free_all(p7bio);
356 sk_X509_free(signers);
357 return ret;
358 }
359
STACK_OF(X509)360 STACK_OF(X509) *PKCS7_get0_signers(PKCS7 *p7, STACK_OF(X509) *certs,
361 int flags)
362 {
363 STACK_OF(X509) *signers;
364 STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
365 PKCS7_SIGNER_INFO *si;
366 PKCS7_ISSUER_AND_SERIAL *ias;
367 X509 *signer;
368 int i;
369
370 if (p7 == NULL) {
371 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_INVALID_NULL_POINTER);
372 return NULL;
373 }
374
375 if (!PKCS7_type_is_signed(p7)) {
376 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
377 return NULL;
378 }
379
380 /* Collect all the signers together */
381
382 sinfos = PKCS7_get_signer_info(p7);
383
384 if (sk_PKCS7_SIGNER_INFO_num(sinfos) <= 0) {
385 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_NO_SIGNERS);
386 return 0;
387 }
388
389 if ((signers = sk_X509_new_null()) == NULL) {
390 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
391 return NULL;
392 }
393
394 for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
395 si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
396 ias = si->issuer_and_serial;
397 signer = NULL;
398 /* If any certificates passed they take priority */
399 if (certs)
400 signer = X509_find_by_issuer_and_serial(certs,
401 ias->issuer, ias->serial);
402 if (!signer && !(flags & PKCS7_NOINTERN)
403 && p7->d.sign->cert)
404 signer =
405 X509_find_by_issuer_and_serial(p7->d.sign->cert,
406 ias->issuer, ias->serial);
407 if (!signer) {
408 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_SIGNER_CERTIFICATE_NOT_FOUND);
409 sk_X509_free(signers);
410 return 0;
411 }
412
413 if (!sk_X509_push(signers, signer)) {
414 sk_X509_free(signers);
415 return NULL;
416 }
417 }
418 return signers;
419 }
420
421 /* Build a complete PKCS#7 enveloped data */
422
PKCS7_encrypt_ex(STACK_OF (X509)* certs,BIO * in,const EVP_CIPHER * cipher,int flags,OSSL_LIB_CTX * libctx,const char * propq)423 PKCS7 *PKCS7_encrypt_ex(STACK_OF(X509) *certs, BIO *in,
424 const EVP_CIPHER *cipher, int flags,
425 OSSL_LIB_CTX *libctx, const char *propq)
426 {
427 PKCS7 *p7;
428 BIO *p7bio = NULL;
429 int i;
430 X509 *x509;
431
432 if ((p7 = PKCS7_new_ex(libctx, propq)) == NULL) {
433 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
434 return NULL;
435 }
436
437 if (!PKCS7_set_type(p7, NID_pkcs7_enveloped))
438 goto err;
439 if (!PKCS7_set_cipher(p7, cipher)) {
440 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_ERROR_SETTING_CIPHER);
441 goto err;
442 }
443
444 for (i = 0; i < sk_X509_num(certs); i++) {
445 x509 = sk_X509_value(certs, i);
446 if (!PKCS7_add_recipient(p7, x509)) {
447 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_ERROR_ADDING_RECIPIENT);
448 goto err;
449 }
450 }
451
452 if (flags & PKCS7_STREAM)
453 return p7;
454
455 if (PKCS7_final(p7, in, flags))
456 return p7;
457
458 err:
459
460 BIO_free_all(p7bio);
461 PKCS7_free(p7);
462 return NULL;
463
464 }
465
PKCS7_encrypt(STACK_OF (X509)* certs,BIO * in,const EVP_CIPHER * cipher,int flags)466 PKCS7 *PKCS7_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher,
467 int flags)
468 {
469 return PKCS7_encrypt_ex(certs, in, cipher, flags, NULL, NULL);
470 }
471
472
PKCS7_decrypt(PKCS7 * p7,EVP_PKEY * pkey,X509 * cert,BIO * data,int flags)473 int PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
474 {
475 BIO *tmpmem;
476 int ret = 0, i;
477 char *buf = NULL;
478
479 if (p7 == NULL) {
480 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_INVALID_NULL_POINTER);
481 return 0;
482 }
483
484 if (!PKCS7_type_is_enveloped(p7)) {
485 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_WRONG_CONTENT_TYPE);
486 return 0;
487 }
488
489 if (cert && !X509_check_private_key(cert, pkey)) {
490 ERR_raise(ERR_LIB_PKCS7,
491 PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
492 return 0;
493 }
494
495 if ((tmpmem = PKCS7_dataDecode(p7, pkey, NULL, cert)) == NULL) {
496 ERR_raise(ERR_LIB_PKCS7, PKCS7_R_DECRYPT_ERROR);
497 return 0;
498 }
499
500 if (flags & PKCS7_TEXT) {
501 BIO *tmpbuf, *bread;
502 /* Encrypt BIOs can't do BIO_gets() so add a buffer BIO */
503 if ((tmpbuf = BIO_new(BIO_f_buffer())) == NULL) {
504 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
505 BIO_free_all(tmpmem);
506 return 0;
507 }
508 if ((bread = BIO_push(tmpbuf, tmpmem)) == NULL) {
509 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
510 BIO_free_all(tmpbuf);
511 BIO_free_all(tmpmem);
512 return 0;
513 }
514 ret = SMIME_text(bread, data);
515 if (ret > 0 && BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
516 if (BIO_get_cipher_status(tmpmem) <= 0)
517 ret = 0;
518 }
519 BIO_free_all(bread);
520 return ret;
521 }
522 if ((buf = OPENSSL_malloc(BUFFERSIZE)) == NULL) {
523 ERR_raise(ERR_LIB_PKCS7, ERR_R_MALLOC_FAILURE);
524 goto err;
525 }
526 for (;;) {
527 i = BIO_read(tmpmem, buf, BUFFERSIZE);
528 if (i <= 0) {
529 ret = 1;
530 if (BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
531 if (BIO_get_cipher_status(tmpmem) <= 0)
532 ret = 0;
533 }
534
535 break;
536 }
537 if (BIO_write(data, buf, i) != i) {
538 break;
539 }
540 }
541 err:
542 OPENSSL_free(buf);
543 BIO_free_all(tmpmem);
544 return ret;
545 }
546
