1 /*	$NetBSD: cms.c,v 1.4 2023/06/19 21:41:44 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 2003 - 2007 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * 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 the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "hx_locl.h"
37 
38 /**
39  * @page page_cms CMS/PKCS7 message functions.
40  *
41  * CMS is defined in RFC 3369 and is an continuation of the RSA Labs
42  * standard PKCS7. The basic messages in CMS is
43  *
44  * - SignedData
45  *   Data signed with private key (RSA, DSA, ECDSA) or secret
46  *   (symmetric) key
47  * - EnvelopedData
48  *   Data encrypted with private key (RSA)
49  * - EncryptedData
50  *   Data encrypted with secret (symmetric) key.
51  * - ContentInfo
52  *   Wrapper structure including type and data.
53  *
54  *
55  * See the library functions here: @ref hx509_cms
56  */
57 
58 #define ALLOC(X, N) (X) = calloc((N), sizeof(*(X)))
59 #define ALLOC_SEQ(X, N) do { (X)->len = (N); ALLOC((X)->val, (N)); } while(0)
60 
61 /**
62  * Wrap data and oid in a ContentInfo and encode it.
63  *
64  * @param oid type of the content.
65  * @param buf data to be wrapped. If a NULL pointer is passed in, the
66  * optional content field in the ContentInfo is not going be filled
67  * in.
68  * @param res the encoded buffer, the result should be freed with
69  * der_free_octet_string().
70  *
71  * @return Returns an hx509 error code.
72  *
73  * @ingroup hx509_cms
74  */
75 
76 int
hx509_cms_wrap_ContentInfo(const heim_oid * oid,const heim_octet_string * buf,heim_octet_string * res)77 hx509_cms_wrap_ContentInfo(const heim_oid *oid,
78 			   const heim_octet_string *buf,
79 			   heim_octet_string *res)
80 {
81     ContentInfo ci;
82     size_t size;
83     int ret;
84 
85     memset(res, 0, sizeof(*res));
86     memset(&ci, 0, sizeof(ci));
87 
88     ret = der_copy_oid(oid, &ci.contentType);
89     if (ret)
90 	return ret;
91     if (buf) {
92 	ALLOC(ci.content, 1);
93 	if (ci.content == NULL) {
94 	    free_ContentInfo(&ci);
95 	    return ENOMEM;
96 	}
97 	ci.content->data = malloc(buf->length);
98 	if (ci.content->data == NULL) {
99 	    free_ContentInfo(&ci);
100 	    return ENOMEM;
101 	}
102 	memcpy(ci.content->data, buf->data, buf->length);
103 	ci.content->length = buf->length;
104     }
105 
106     ASN1_MALLOC_ENCODE(ContentInfo, res->data, res->length, &ci, &size, ret);
107     free_ContentInfo(&ci);
108     if (ret)
109 	return ret;
110     if (res->length != size)
111 	_hx509_abort("internal ASN.1 encoder error");
112 
113     return 0;
114 }
115 
116 /**
117  * Decode an ContentInfo and unwrap data and oid it.
118  *
119  * @param in the encoded buffer.
120  * @param oid type of the content.
121  * @param out data to be wrapped.
122  * @param have_data since the data is optional, this flags show dthe
123  * diffrence between no data and the zero length data.
124  *
125  * @return Returns an hx509 error code.
126  *
127  * @ingroup hx509_cms
128  */
129 
130 int
hx509_cms_unwrap_ContentInfo(const heim_octet_string * in,heim_oid * oid,heim_octet_string * out,int * have_data)131 hx509_cms_unwrap_ContentInfo(const heim_octet_string *in,
132 			     heim_oid *oid,
133 			     heim_octet_string *out,
134 			     int *have_data)
135 {
136     ContentInfo ci;
137     size_t size;
138     int ret;
139 
140     memset(oid, 0, sizeof(*oid));
141     memset(out, 0, sizeof(*out));
142 
143     ret = decode_ContentInfo(in->data, in->length, &ci, &size);
144     if (ret)
145 	return ret;
146 
147     ret = der_copy_oid(&ci.contentType, oid);
148     if (ret) {
149 	free_ContentInfo(&ci);
150 	return ret;
151     }
152     if (ci.content) {
153 	ret = der_copy_octet_string(ci.content, out);
154 	if (ret) {
155 	    der_free_oid(oid);
156 	    free_ContentInfo(&ci);
157 	    return ret;
158 	}
159     } else
160 	memset(out, 0, sizeof(*out));
161 
162     if (have_data)
163 	*have_data = (ci.content != NULL) ? 1 : 0;
164 
165     free_ContentInfo(&ci);
166 
167     return 0;
168 }
169 
170 #define CMS_ID_SKI	0
171 #define CMS_ID_NAME	1
172 
173 static int
fill_CMSIdentifier(const hx509_cert cert,int type,CMSIdentifier * id)174 fill_CMSIdentifier(const hx509_cert cert,
175 		   int type,
176 		   CMSIdentifier *id)
177 {
178     int ret;
179 
180     switch (type) {
181     case CMS_ID_SKI:
182 	id->element = choice_CMSIdentifier_subjectKeyIdentifier;
183 	ret = _hx509_find_extension_subject_key_id(_hx509_get_cert(cert),
184 						   &id->u.subjectKeyIdentifier);
185 	if (ret == 0)
186 	    break;
187 	/* FALLTHROUGH */
188     case CMS_ID_NAME: {
189 	hx509_name name;
190 
191 	id->element = choice_CMSIdentifier_issuerAndSerialNumber;
192 	ret = hx509_cert_get_issuer(cert, &name);
193 	if (ret)
194 	    return ret;
195 	ret = hx509_name_to_Name(name, &id->u.issuerAndSerialNumber.issuer);
196 	hx509_name_free(&name);
197 	if (ret)
198 	    return ret;
199 
200 	ret = hx509_cert_get_serialnumber(cert, &id->u.issuerAndSerialNumber.serialNumber);
201 	break;
202     }
203     default:
204 	_hx509_abort("CMS fill identifier with unknown type");
205     }
206     return ret;
207 }
208 
209 static int
unparse_CMSIdentifier(hx509_context context,CMSIdentifier * id,char ** str)210 unparse_CMSIdentifier(hx509_context context,
211 		      CMSIdentifier *id,
212 		      char **str)
213 {
214     int ret = -1;
215 
216     *str = NULL;
217     switch (id->element) {
218     case choice_CMSIdentifier_issuerAndSerialNumber: {
219 	IssuerAndSerialNumber *iasn;
220 	char *serial, *name;
221 
222 	iasn = &id->u.issuerAndSerialNumber;
223 
224 	ret = _hx509_Name_to_string(&iasn->issuer, &name);
225 	if(ret)
226 	    return ret;
227 	ret = der_print_hex_heim_integer(&iasn->serialNumber, &serial);
228 	if (ret) {
229 	    free(name);
230 	    return ret;
231 	}
232 	ret = asprintf(str, "certificate issued by %s with serial number %s",
233 		       name, serial);
234 	free(name);
235 	free(serial);
236 	break;
237     }
238     case choice_CMSIdentifier_subjectKeyIdentifier: {
239 	KeyIdentifier *ki  = &id->u.subjectKeyIdentifier;
240 	char *keyid;
241 	ssize_t len;
242 
243 	len = hex_encode(ki->data, ki->length, &keyid);
244 	if (len < 0)
245 	    return ENOMEM;
246 
247 	ret = asprintf(str, "certificate with id %s", keyid);
248 	free(keyid);
249 	break;
250     }
251     default:
252 	ret = asprintf(str, "certificate have unknown CMSidentifier type");
253 	break;
254     }
255     /*
256      * In the following if, we check ret and *str which should be returned/set
257      * by asprintf(3) in every branch of the switch statement.
258      */
259     if (ret == -1 || *str == NULL)
260 	return ENOMEM;
261     return 0;
262 }
263 
264 static int
find_CMSIdentifier(hx509_context context,CMSIdentifier * client,hx509_certs certs,time_t time_now,hx509_cert * signer_cert,int match)265 find_CMSIdentifier(hx509_context context,
266 		   CMSIdentifier *client,
267 		   hx509_certs certs,
268 		   time_t time_now,
269 		   hx509_cert *signer_cert,
270 		   int match)
271 {
272     hx509_query q;
273     hx509_cert cert;
274     Certificate c;
275     int ret;
276 
277     memset(&c, 0, sizeof(c));
278     _hx509_query_clear(&q);
279 
280     *signer_cert = NULL;
281 
282     switch (client->element) {
283     case choice_CMSIdentifier_issuerAndSerialNumber:
284 	q.serial = &client->u.issuerAndSerialNumber.serialNumber;
285 	q.issuer_name = &client->u.issuerAndSerialNumber.issuer;
286 	q.match = HX509_QUERY_MATCH_SERIALNUMBER|HX509_QUERY_MATCH_ISSUER_NAME;
287 	break;
288     case choice_CMSIdentifier_subjectKeyIdentifier:
289 	q.subject_id = &client->u.subjectKeyIdentifier;
290 	q.match = HX509_QUERY_MATCH_SUBJECT_KEY_ID;
291 	break;
292     default:
293 	hx509_set_error_string(context, 0, HX509_CMS_NO_RECIPIENT_CERTIFICATE,
294 			       "unknown CMS identifier element");
295 	return HX509_CMS_NO_RECIPIENT_CERTIFICATE;
296     }
297 
298     q.match |= match;
299 
300     q.match |= HX509_QUERY_MATCH_TIME;
301     if (time_now)
302 	q.timenow = time_now;
303     else
304 	q.timenow = time(NULL);
305 
306     ret = hx509_certs_find(context, certs, &q, &cert);
307     if (ret == HX509_CERT_NOT_FOUND) {
308 	char *str;
309 
310 	ret = unparse_CMSIdentifier(context, client, &str);
311 	if (ret == 0) {
312 	    hx509_set_error_string(context, 0,
313 				   HX509_CMS_NO_RECIPIENT_CERTIFICATE,
314 				   "Failed to find %s", str);
315 	} else
316 	    hx509_clear_error_string(context);
317 	return HX509_CMS_NO_RECIPIENT_CERTIFICATE;
318     } else if (ret) {
319 	hx509_set_error_string(context, HX509_ERROR_APPEND,
320 			       HX509_CMS_NO_RECIPIENT_CERTIFICATE,
321 			       "Failed to find CMS id in cert store");
322 	return HX509_CMS_NO_RECIPIENT_CERTIFICATE;
323     }
324 
325     *signer_cert = cert;
326 
327     return 0;
328 }
329 
330 /**
331  * Decode and unencrypt EnvelopedData.
332  *
333  * Extract data and parameteres from from the EnvelopedData. Also
334  * supports using detached EnvelopedData.
335  *
336  * @param context A hx509 context.
337  * @param certs Certificate that can decrypt the EnvelopedData
338  * encryption key.
339  * @param flags HX509_CMS_UE flags to control the behavior.
340  * @param data pointer the structure the contains the DER/BER encoded
341  * EnvelopedData stucture.
342  * @param length length of the data that data point to.
343  * @param encryptedContent in case of detached signature, this
344  * contains the actual encrypted data, othersize its should be NULL.
345  * @param time_now set the current time, if zero the library uses now as the date.
346  * @param contentType output type oid, should be freed with der_free_oid().
347  * @param content the data, free with der_free_octet_string().
348  *
349  * @return an hx509 error code.
350  *
351  * @ingroup hx509_cms
352  */
353 
354 int
hx509_cms_unenvelope(hx509_context context,hx509_certs certs,int flags,const void * data,size_t length,const heim_octet_string * encryptedContent,time_t time_now,heim_oid * contentType,heim_octet_string * content)355 hx509_cms_unenvelope(hx509_context context,
356 		     hx509_certs certs,
357 		     int flags,
358 		     const void *data,
359 		     size_t length,
360 		     const heim_octet_string *encryptedContent,
361 		     time_t time_now,
362 		     heim_oid *contentType,
363 		     heim_octet_string *content)
364 {
365     heim_octet_string key;
366     EnvelopedData ed;
367     hx509_cert cert;
368     AlgorithmIdentifier *ai;
369     const heim_octet_string *enccontent;
370     heim_octet_string *params, params_data;
371     heim_octet_string ivec;
372     size_t size;
373     int ret, matched = 0, findflags = 0;
374     size_t i;
375 
376 
377     memset(&key, 0, sizeof(key));
378     memset(&ed, 0, sizeof(ed));
379     memset(&ivec, 0, sizeof(ivec));
380     memset(content, 0, sizeof(*content));
381     memset(contentType, 0, sizeof(*contentType));
382 
383     if ((flags & HX509_CMS_UE_DONT_REQUIRE_KU_ENCIPHERMENT) == 0)
384 	findflags |= HX509_QUERY_KU_ENCIPHERMENT;
385 
386     ret = decode_EnvelopedData(data, length, &ed, &size);
387     if (ret) {
388 	hx509_set_error_string(context, 0, ret,
389 			       "Failed to decode EnvelopedData");
390 	return ret;
391     }
392 
393     if (ed.recipientInfos.len == 0) {
394 	ret = HX509_CMS_NO_RECIPIENT_CERTIFICATE;
395 	hx509_set_error_string(context, 0, ret,
396 			       "No recipient info in enveloped data");
397 	goto out;
398     }
399 
400     enccontent = ed.encryptedContentInfo.encryptedContent;
401     if (enccontent == NULL) {
402 	if (encryptedContent == NULL) {
403 	    ret = HX509_CMS_NO_DATA_AVAILABLE;
404 	    hx509_set_error_string(context, 0, ret,
405 				   "Content missing from encrypted data");
406 	    goto out;
407 	}
408 	enccontent = encryptedContent;
409     } else if (encryptedContent != NULL) {
410 	ret = HX509_CMS_NO_DATA_AVAILABLE;
411 	hx509_set_error_string(context, 0, ret,
412 			       "Both internal and external encrypted data");
413 	goto out;
414     }
415 
416     cert = NULL;
417     for (i = 0; i < ed.recipientInfos.len; i++) {
418 	KeyTransRecipientInfo *ri;
419 	char *str;
420 	int ret2;
421 
422 	ri = &ed.recipientInfos.val[i];
423 
424 	ret = find_CMSIdentifier(context, &ri->rid, certs,
425 				 time_now, &cert,
426 				 HX509_QUERY_PRIVATE_KEY|findflags);
427 	if (ret)
428 	    continue;
429 
430 	matched = 1; /* found a matching certificate, let decrypt */
431 
432 	ret = _hx509_cert_private_decrypt(context,
433 					  &ri->encryptedKey,
434 					  &ri->keyEncryptionAlgorithm.algorithm,
435 					  cert, &key);
436 
437 	hx509_cert_free(cert);
438 	if (ret == 0)
439 	    break; /* succuessfully decrypted cert */
440 	cert = NULL;
441 	ret2 = unparse_CMSIdentifier(context, &ri->rid, &str);
442 	if (ret2 == 0) {
443 	    hx509_set_error_string(context, HX509_ERROR_APPEND, ret,
444 				   "Failed to decrypt with %s", str);
445 	    free(str);
446 	}
447     }
448 
449     if (!matched) {
450 	ret = HX509_CMS_NO_RECIPIENT_CERTIFICATE;
451 	hx509_set_error_string(context, 0, ret,
452 			       "No private key matched any certificate");
453 	goto out;
454     }
455 
456     if (cert == NULL) {
457 	ret = HX509_CMS_NO_RECIPIENT_CERTIFICATE;
458 	hx509_set_error_string(context, HX509_ERROR_APPEND, ret,
459 			       "No private key decrypted the transfer key");
460 	goto out;
461     }
462 
463     ret = der_copy_oid(&ed.encryptedContentInfo.contentType, contentType);
464     if (ret) {
465 	hx509_set_error_string(context, 0, ret,
466 			       "Failed to copy EnvelopedData content oid");
467 	goto out;
468     }
469 
470     ai = &ed.encryptedContentInfo.contentEncryptionAlgorithm;
471     if (ai->parameters) {
472 	params_data.data = ai->parameters->data;
473 	params_data.length = ai->parameters->length;
474 	params = &params_data;
475     } else
476 	params = NULL;
477 
478     {
479 	hx509_crypto crypto;
480 
481 	ret = hx509_crypto_init(context, NULL, &ai->algorithm, &crypto);
482 	if (ret)
483 	    goto out;
484 
485 	if (flags & HX509_CMS_UE_ALLOW_WEAK)
486 	    hx509_crypto_allow_weak(crypto);
487 
488 	if (params) {
489 	    ret = hx509_crypto_set_params(context, crypto, params, &ivec);
490 	    if (ret) {
491 		hx509_crypto_destroy(crypto);
492 		goto out;
493 	    }
494 	}
495 
496 	ret = hx509_crypto_set_key_data(crypto, key.data, key.length);
497 	if (ret) {
498 	    hx509_crypto_destroy(crypto);
499 	    hx509_set_error_string(context, 0, ret,
500 				   "Failed to set key for decryption "
501 				   "of EnvelopedData");
502 	    goto out;
503 	}
504 
505 	ret = hx509_crypto_decrypt(crypto,
506 				   enccontent->data,
507 				   enccontent->length,
508 				   ivec.length ? &ivec : NULL,
509 				   content);
510 	hx509_crypto_destroy(crypto);
511 	if (ret) {
512 	    hx509_set_error_string(context, 0, ret,
513 				   "Failed to decrypt EnvelopedData");
514 	    goto out;
515 	}
516     }
517 
518 out:
519 
520     free_EnvelopedData(&ed);
521     der_free_octet_string(&key);
522     if (ivec.length)
523 	der_free_octet_string(&ivec);
524     if (ret) {
525 	der_free_oid(contentType);
526 	der_free_octet_string(content);
527     }
528 
529     return ret;
530 }
531 
532 /**
533  * Encrypt end encode EnvelopedData.
534  *
535  * Encrypt and encode EnvelopedData. The data is encrypted with a
536  * random key and the the random key is encrypted with the
537  * certificates private key. This limits what private key type can be
538  * used to RSA.
539  *
540  * @param context A hx509 context.
541  * @param flags flags to control the behavior.
542  *    - HX509_CMS_EV_NO_KU_CHECK - Don't check KU on certificate
543  *    - HX509_CMS_EV_ALLOW_WEAK - Allow weak crytpo
544  *    - HX509_CMS_EV_ID_NAME - prefer issuer name and serial number
545  * @param cert Certificate to encrypt the EnvelopedData encryption key
546  * with.
547  * @param data pointer the data to encrypt.
548  * @param length length of the data that data point to.
549  * @param encryption_type Encryption cipher to use for the bulk data,
550  * use NULL to get default.
551  * @param contentType type of the data that is encrypted
552  * @param content the output of the function,
553  * free with der_free_octet_string().
554  *
555  * @return an hx509 error code.
556  *
557  * @ingroup hx509_cms
558  */
559 
560 int
hx509_cms_envelope_1(hx509_context context,int flags,hx509_cert cert,const void * data,size_t length,const heim_oid * encryption_type,const heim_oid * contentType,heim_octet_string * content)561 hx509_cms_envelope_1(hx509_context context,
562 		     int flags,
563 		     hx509_cert cert,
564 		     const void *data,
565 		     size_t length,
566 		     const heim_oid *encryption_type,
567 		     const heim_oid *contentType,
568 		     heim_octet_string *content)
569 {
570     KeyTransRecipientInfo *ri;
571     heim_octet_string ivec;
572     heim_octet_string key;
573     hx509_crypto crypto = NULL;
574     int ret, cmsidflag;
575     EnvelopedData ed;
576     size_t size;
577 
578     memset(&ivec, 0, sizeof(ivec));
579     memset(&key, 0, sizeof(key));
580     memset(&ed, 0, sizeof(ed));
581     memset(content, 0, sizeof(*content));
582 
583     if (encryption_type == NULL)
584 	encryption_type = &asn1_oid_id_aes_256_cbc;
585 
586     if ((flags & HX509_CMS_EV_NO_KU_CHECK) == 0) {
587 	ret = _hx509_check_key_usage(context, cert, 1 << 2, TRUE);
588 	if (ret)
589 	    goto out;
590     }
591 
592     ret = hx509_crypto_init(context, NULL, encryption_type, &crypto);
593     if (ret)
594 	goto out;
595 
596     if (flags & HX509_CMS_EV_ALLOW_WEAK)
597 	hx509_crypto_allow_weak(crypto);
598 
599     ret = hx509_crypto_set_random_key(crypto, &key);
600     if (ret) {
601 	hx509_set_error_string(context, 0, ret,
602 			       "Create random key for EnvelopedData content");
603 	goto out;
604     }
605 
606     ret = hx509_crypto_random_iv(crypto, &ivec);
607     if (ret) {
608 	hx509_set_error_string(context, 0, ret,
609 			       "Failed to create a random iv");
610 	goto out;
611     }
612 
613     ret = hx509_crypto_encrypt(crypto,
614 			       data,
615 			       length,
616 			       &ivec,
617 			       &ed.encryptedContentInfo.encryptedContent);
618     if (ret) {
619 	hx509_set_error_string(context, 0, ret,
620 			       "Failed to encrypt EnvelopedData content");
621 	goto out;
622     }
623 
624     {
625 	AlgorithmIdentifier *enc_alg;
626 	enc_alg = &ed.encryptedContentInfo.contentEncryptionAlgorithm;
627 	ret = der_copy_oid(encryption_type, &enc_alg->algorithm);
628 	if (ret) {
629 	    hx509_set_error_string(context, 0, ret,
630 				   "Failed to set crypto oid "
631 				   "for EnvelopedData");
632 	    goto out;
633 	}
634 	ALLOC(enc_alg->parameters, 1);
635 	if (enc_alg->parameters == NULL) {
636 	    ret = ENOMEM;
637 	    hx509_set_error_string(context, 0, ret,
638 				   "Failed to allocate crypto paramaters "
639 				   "for EnvelopedData");
640 	    goto out;
641 	}
642 
643 	ret = hx509_crypto_get_params(context,
644 				      crypto,
645 				      &ivec,
646 				      enc_alg->parameters);
647 	if (ret) {
648 	    goto out;
649 	}
650     }
651 
652     ALLOC_SEQ(&ed.recipientInfos, 1);
653     if (ed.recipientInfos.val == NULL) {
654 	ret = ENOMEM;
655 	hx509_set_error_string(context, 0, ret,
656 			       "Failed to allocate recipients info "
657 			       "for EnvelopedData");
658 	goto out;
659     }
660 
661     ri = &ed.recipientInfos.val[0];
662 
663     if (flags & HX509_CMS_EV_ID_NAME) {
664 	ri->version = 0;
665 	cmsidflag = CMS_ID_NAME;
666     } else {
667 	ri->version = 2;
668 	cmsidflag = CMS_ID_SKI;
669     }
670 
671     ret = fill_CMSIdentifier(cert, cmsidflag, &ri->rid);
672     if (ret) {
673 	hx509_set_error_string(context, 0, ret,
674 			       "Failed to set CMS identifier info "
675 			       "for EnvelopedData");
676 	goto out;
677     }
678 
679     ret = hx509_cert_public_encrypt(context,
680 				     &key, cert,
681 				     &ri->keyEncryptionAlgorithm.algorithm,
682 				     &ri->encryptedKey);
683     if (ret) {
684 	hx509_set_error_string(context, HX509_ERROR_APPEND, ret,
685 			       "Failed to encrypt transport key for "
686 			       "EnvelopedData");
687 	goto out;
688     }
689 
690     /*
691      *
692      */
693 
694     ed.version = 0;
695     ed.originatorInfo = NULL;
696 
697     ret = der_copy_oid(contentType, &ed.encryptedContentInfo.contentType);
698     if (ret) {
699 	hx509_set_error_string(context, 0, ret,
700 			       "Failed to copy content oid for "
701 			       "EnvelopedData");
702 	goto out;
703     }
704 
705     ed.unprotectedAttrs = NULL;
706 
707     ASN1_MALLOC_ENCODE(EnvelopedData, content->data, content->length,
708 		       &ed, &size, ret);
709     if (ret) {
710 	hx509_set_error_string(context, 0, ret,
711 			       "Failed to encode EnvelopedData");
712 	goto out;
713     }
714     if (size != content->length)
715 	_hx509_abort("internal ASN.1 encoder error");
716 
717 out:
718     if (crypto)
719 	hx509_crypto_destroy(crypto);
720     if (ret)
721 	der_free_octet_string(content);
722     der_free_octet_string(&key);
723     der_free_octet_string(&ivec);
724     free_EnvelopedData(&ed);
725 
726     return ret;
727 }
728 
729 static int
any_to_certs(hx509_context context,const SignedData * sd,hx509_certs certs)730 any_to_certs(hx509_context context, const SignedData *sd, hx509_certs certs)
731 {
732     int ret;
733     size_t i;
734 
735     if (sd->certificates == NULL)
736 	return 0;
737 
738     for (i = 0; i < sd->certificates->len; i++) {
739 	heim_error_t error;
740 	hx509_cert c;
741 
742 	c = hx509_cert_init_data(context,
743 				 sd->certificates->val[i].data,
744 				 sd->certificates->val[i].length,
745 				 &error);
746 	if (c == NULL) {
747 	    ret = heim_error_get_code(error);
748 	    heim_release(error);
749 	    return ret;
750 	}
751 	ret = hx509_certs_add(context, certs, c);
752 	hx509_cert_free(c);
753 	if (ret)
754 	    return ret;
755     }
756 
757     return 0;
758 }
759 
760 static const Attribute *
find_attribute(const CMSAttributes * attr,const heim_oid * oid)761 find_attribute(const CMSAttributes *attr, const heim_oid *oid)
762 {
763     size_t i;
764     for (i = 0; i < attr->len; i++)
765 	if (der_heim_oid_cmp(&attr->val[i].type, oid) == 0)
766 	    return &attr->val[i];
767     return NULL;
768 }
769 
770 /**
771  * Decode SignedData and verify that the signature is correct.
772  *
773  * @param context A hx509 context.
774  * @param ctx a hx509 verify context.
775  * @param flags to control the behaivor of the function.
776  *    - HX509_CMS_VS_NO_KU_CHECK - Don't check KeyUsage
777  *    - HX509_CMS_VS_ALLOW_DATA_OID_MISMATCH - allow oid mismatch
778  *    - HX509_CMS_VS_ALLOW_ZERO_SIGNER - no signer, see below.
779  * @param data pointer to CMS SignedData encoded data.
780  * @param length length of the data that data point to.
781  * @param signedContent external data used for signature.
782  * @param pool certificate pool to build certificates paths.
783  * @param contentType free with der_free_oid().
784  * @param content the output of the function, free with
785  * der_free_octet_string().
786  * @param signer_certs list of the cerficates used to sign this
787  * request, free with hx509_certs_free().
788  *
789  * @return an hx509 error code.
790  *
791  * @ingroup hx509_cms
792  */
793 
794 int
hx509_cms_verify_signed(hx509_context context,hx509_verify_ctx ctx,unsigned int flags,const void * data,size_t length,const heim_octet_string * signedContent,hx509_certs pool,heim_oid * contentType,heim_octet_string * content,hx509_certs * signer_certs)795 hx509_cms_verify_signed(hx509_context context,
796 			hx509_verify_ctx ctx,
797 			unsigned int flags,
798 			const void *data,
799 			size_t length,
800 			const heim_octet_string *signedContent,
801 			hx509_certs pool,
802 			heim_oid *contentType,
803 			heim_octet_string *content,
804 			hx509_certs *signer_certs)
805 {
806     SignerInfo *signer_info;
807     hx509_cert cert = NULL;
808     hx509_certs certs = NULL;
809     SignedData sd;
810     size_t size;
811     int ret, found_valid_sig;
812     size_t i;
813 
814     *signer_certs = NULL;
815     content->data = NULL;
816     content->length = 0;
817     contentType->length = 0;
818     contentType->components = NULL;
819 
820     memset(&sd, 0, sizeof(sd));
821 
822     ret = decode_SignedData(data, length, &sd, &size);
823     if (ret) {
824 	hx509_set_error_string(context, 0, ret,
825 			       "Failed to decode SignedData");
826 	goto out;
827     }
828 
829     if (sd.encapContentInfo.eContent == NULL && signedContent == NULL) {
830 	ret = HX509_CMS_NO_DATA_AVAILABLE;
831 	hx509_set_error_string(context, 0, ret,
832 			       "No content data in SignedData");
833 	goto out;
834     }
835     if (sd.encapContentInfo.eContent && signedContent) {
836 	ret = HX509_CMS_NO_DATA_AVAILABLE;
837 	hx509_set_error_string(context, 0, ret,
838 			       "Both external and internal SignedData");
839 	goto out;
840     }
841 
842     if (sd.encapContentInfo.eContent)
843 	ret = der_copy_octet_string(sd.encapContentInfo.eContent, content);
844     else
845 	ret = der_copy_octet_string(signedContent, content);
846     if (ret) {
847 	hx509_set_error_string(context, 0, ret, "malloc: out of memory");
848 	goto out;
849     }
850 
851     ret = hx509_certs_init(context, "MEMORY:cms-cert-buffer",
852 			   0, NULL, &certs);
853     if (ret)
854 	goto out;
855 
856     ret = hx509_certs_init(context, "MEMORY:cms-signer-certs",
857 			   0, NULL, signer_certs);
858     if (ret)
859 	goto out;
860 
861     /* XXX Check CMS version */
862 
863     ret = any_to_certs(context, &sd, certs);
864     if (ret)
865 	goto out;
866 
867     if (pool) {
868 	ret = hx509_certs_merge(context, certs, pool);
869 	if (ret)
870 	    goto out;
871     }
872 
873     for (found_valid_sig = 0, i = 0; i < sd.signerInfos.len; i++) {
874 	heim_octet_string signed_data = { 0, 0 };
875 	const heim_oid *match_oid;
876 	heim_oid decode_oid;
877 
878 	signer_info = &sd.signerInfos.val[i];
879 	match_oid = NULL;
880 
881 	if (signer_info->signature.length == 0) {
882 	    ret = HX509_CMS_MISSING_SIGNER_DATA;
883 	    hx509_set_error_string(context, 0, ret,
884 				   "SignerInfo %d in SignedData "
885 				   "missing sigature", i);
886 	    continue;
887 	}
888 
889 	ret = find_CMSIdentifier(context, &signer_info->sid, certs,
890 				 _hx509_verify_get_time(ctx), &cert,
891 				 HX509_QUERY_KU_DIGITALSIGNATURE);
892 	if (ret) {
893 	    /**
894 	     * If HX509_CMS_VS_NO_KU_CHECK is set, allow more liberal
895 	     * search for matching certificates by not considering
896 	     * KeyUsage bits on the certificates.
897 	     */
898 	    if ((flags & HX509_CMS_VS_NO_KU_CHECK) == 0)
899 		continue;
900 
901 	    ret = find_CMSIdentifier(context, &signer_info->sid, certs,
902 				     _hx509_verify_get_time(ctx), &cert,
903 				     0);
904 	    if (ret)
905 		continue;
906 
907 	}
908 
909 	if (signer_info->signedAttrs) {
910 	    const Attribute *attr;
911 
912 	    CMSAttributes sa;
913 	    heim_octet_string os;
914 
915 	    sa.val = signer_info->signedAttrs->val;
916 	    sa.len = signer_info->signedAttrs->len;
917 
918 	    /* verify that sigature exists */
919 	    attr = find_attribute(&sa, &asn1_oid_id_pkcs9_messageDigest);
920 	    if (attr == NULL) {
921 		ret = HX509_CRYPTO_SIGNATURE_MISSING;
922 		hx509_set_error_string(context, 0, ret,
923 				       "SignerInfo have signed attributes "
924 				       "but messageDigest (signature) "
925 				       "is missing");
926 		goto next_sigature;
927 	    }
928 	    if (attr->value.len != 1) {
929 		ret = HX509_CRYPTO_SIGNATURE_MISSING;
930 		hx509_set_error_string(context, 0, ret,
931 				       "SignerInfo have more then one "
932 				       "messageDigest (signature)");
933 		goto next_sigature;
934 	    }
935 
936 	    ret = decode_MessageDigest(attr->value.val[0].data,
937 				       attr->value.val[0].length,
938 				       &os,
939 				       &size);
940 	    if (ret) {
941 		hx509_set_error_string(context, 0, ret,
942 				       "Failed to decode "
943 				       "messageDigest (signature)");
944 		goto next_sigature;
945 	    }
946 
947 	    ret = _hx509_verify_signature(context,
948 					  NULL,
949 					  &signer_info->digestAlgorithm,
950 					  content,
951 					  &os);
952 	    der_free_octet_string(&os);
953 	    if (ret) {
954 		hx509_set_error_string(context, HX509_ERROR_APPEND, ret,
955 				       "Failed to verify messageDigest");
956 		goto next_sigature;
957 	    }
958 
959 	    /*
960 	     * Fetch content oid inside signedAttrs or set it to
961 	     * id-pkcs7-data.
962 	     */
963 	    attr = find_attribute(&sa, &asn1_oid_id_pkcs9_contentType);
964 	    if (attr == NULL) {
965 		match_oid = &asn1_oid_id_pkcs7_data;
966 	    } else {
967 		if (attr->value.len != 1) {
968 		    ret = HX509_CMS_DATA_OID_MISMATCH;
969 		    hx509_set_error_string(context, 0, ret,
970 					   "More then one oid in signedAttrs");
971 		    goto next_sigature;
972 
973 		}
974 		ret = decode_ContentType(attr->value.val[0].data,
975 					 attr->value.val[0].length,
976 					 &decode_oid,
977 					 &size);
978 		if (ret) {
979 		    hx509_set_error_string(context, 0, ret,
980 					   "Failed to decode "
981 					   "oid in signedAttrs");
982 		    goto next_sigature;
983 		}
984 		match_oid = &decode_oid;
985 	    }
986 
987 	    ASN1_MALLOC_ENCODE(CMSAttributes,
988 			       signed_data.data,
989 			       signed_data.length,
990 			       &sa,
991 			       &size, ret);
992 	    if (ret) {
993 		if (match_oid == &decode_oid)
994 		    der_free_oid(&decode_oid);
995 		hx509_clear_error_string(context);
996 		goto next_sigature;
997 	    }
998 	    if (size != signed_data.length)
999 		_hx509_abort("internal ASN.1 encoder error");
1000 
1001 	} else {
1002 	    signed_data.data = content->data;
1003 	    signed_data.length = content->length;
1004 	    match_oid = &asn1_oid_id_pkcs7_data;
1005 	}
1006 
1007 	/**
1008 	 * If HX509_CMS_VS_ALLOW_DATA_OID_MISMATCH, allow
1009 	 * encapContentInfo mismatch with the oid in signedAttributes
1010 	 * (or if no signedAttributes where use, pkcs7-data oid).
1011 	 * This is only needed to work with broken CMS implementations
1012 	 * that doesn't follow CMS signedAttributes rules.
1013 	 */
1014 
1015 	if (der_heim_oid_cmp(match_oid, &sd.encapContentInfo.eContentType) &&
1016 	    (flags & HX509_CMS_VS_ALLOW_DATA_OID_MISMATCH) == 0) {
1017 	    ret = HX509_CMS_DATA_OID_MISMATCH;
1018 	    hx509_set_error_string(context, 0, ret,
1019 				   "Oid in message mismatch from the expected");
1020 	}
1021 	if (match_oid == &decode_oid)
1022 	    der_free_oid(&decode_oid);
1023 
1024 	if (ret == 0) {
1025 	    ret = hx509_verify_signature(context,
1026 					 cert,
1027 					 &signer_info->signatureAlgorithm,
1028 					 &signed_data,
1029 					 &signer_info->signature);
1030 	    if (ret)
1031 		hx509_set_error_string(context, HX509_ERROR_APPEND, ret,
1032 				       "Failed to verify signature in "
1033 				       "CMS SignedData");
1034 	}
1035         if (signed_data.data != NULL && content->data != signed_data.data) {
1036             free(signed_data.data);
1037             signed_data.data = NULL;
1038         }
1039 	if (ret)
1040 	    goto next_sigature;
1041 
1042 	/**
1043 	 * If HX509_CMS_VS_NO_VALIDATE flags is set, do not verify the
1044 	 * signing certificates and leave that up to the caller.
1045 	 */
1046 
1047 	if ((flags & HX509_CMS_VS_NO_VALIDATE) == 0) {
1048 	    ret = hx509_verify_path(context, ctx, cert, certs);
1049 	    if (ret)
1050 		goto next_sigature;
1051 	}
1052 
1053 	ret = hx509_certs_add(context, *signer_certs, cert);
1054 	if (ret)
1055 	    goto next_sigature;
1056 
1057 	found_valid_sig++;
1058 
1059     next_sigature:
1060 	if (cert)
1061 	    hx509_cert_free(cert);
1062 	cert = NULL;
1063     }
1064     /**
1065      * If HX509_CMS_VS_ALLOW_ZERO_SIGNER is set, allow empty
1066      * SignerInfo (no signatures). If SignedData have no signatures,
1067      * the function will return 0 with signer_certs set to NULL. Zero
1068      * signers is allowed by the standard, but since its only useful
1069      * in corner cases, it make into a flag that the caller have to
1070      * turn on.
1071      */
1072     if (sd.signerInfos.len == 0 && (flags & HX509_CMS_VS_ALLOW_ZERO_SIGNER)) {
1073 	if (*signer_certs)
1074 	    hx509_certs_free(signer_certs);
1075     } else if (found_valid_sig == 0) {
1076 	if (ret == 0) {
1077 	    ret = HX509_CMS_SIGNER_NOT_FOUND;
1078 	    hx509_set_error_string(context, 0, ret,
1079 				   "No signers where found");
1080 	}
1081 	goto out;
1082     }
1083 
1084     ret = der_copy_oid(&sd.encapContentInfo.eContentType, contentType);
1085     if (ret) {
1086 	hx509_clear_error_string(context);
1087 	goto out;
1088     }
1089 
1090 out:
1091     free_SignedData(&sd);
1092     if (certs)
1093 	hx509_certs_free(&certs);
1094     if (ret) {
1095 	if (content->data)
1096 	    der_free_octet_string(content);
1097 	if (*signer_certs)
1098 	    hx509_certs_free(signer_certs);
1099 	der_free_oid(contentType);
1100 	der_free_octet_string(content);
1101     }
1102 
1103     return ret;
1104 }
1105 
1106 static int
add_one_attribute(Attribute ** attr,unsigned int * len,const heim_oid * oid,heim_octet_string * data)1107 add_one_attribute(Attribute **attr,
1108 		  unsigned int *len,
1109 		  const heim_oid *oid,
1110 		  heim_octet_string *data)
1111 {
1112     void *d;
1113     int ret;
1114 
1115     d = realloc(*attr, sizeof((*attr)[0]) * (*len + 1));
1116     if (d == NULL)
1117 	return ENOMEM;
1118     (*attr) = d;
1119 
1120     ret = der_copy_oid(oid, &(*attr)[*len].type);
1121     if (ret)
1122 	return ret;
1123 
1124     ALLOC_SEQ(&(*attr)[*len].value, 1);
1125     if ((*attr)[*len].value.val == NULL) {
1126 	der_free_oid(&(*attr)[*len].type);
1127 	return ENOMEM;
1128     }
1129 
1130     (*attr)[*len].value.val[0].data = data->data;
1131     (*attr)[*len].value.val[0].length = data->length;
1132 
1133     *len += 1;
1134 
1135     return 0;
1136 }
1137 
1138 /**
1139  * Decode SignedData and verify that the signature is correct.
1140  *
1141  * @param context A hx509 context.
1142  * @param flags
1143  * @param eContentType the type of the data.
1144  * @param data data to sign
1145  * @param length length of the data that data point to.
1146  * @param digest_alg digest algorithm to use, use NULL to get the
1147  * default or the peer determined algorithm.
1148  * @param cert certificate to use for sign the data.
1149  * @param peer info about the peer the message to send the message to,
1150  * like what digest algorithm to use.
1151  * @param anchors trust anchors that the client will use, used to
1152  * polulate the certificates included in the message
1153  * @param pool certificates to use in try to build the path to the
1154  * trust anchors.
1155  * @param signed_data the output of the function, free with
1156  * der_free_octet_string().
1157  *
1158  * @return Returns an hx509 error code.
1159  *
1160  * @ingroup hx509_cms
1161  */
1162 
1163 int
hx509_cms_create_signed_1(hx509_context context,int flags,const heim_oid * eContentType,const void * data,size_t length,const AlgorithmIdentifier * digest_alg,hx509_cert cert,hx509_peer_info peer,hx509_certs anchors,hx509_certs pool,heim_octet_string * signed_data)1164 hx509_cms_create_signed_1(hx509_context context,
1165 			  int flags,
1166 			  const heim_oid *eContentType,
1167 			  const void *data, size_t length,
1168 			  const AlgorithmIdentifier *digest_alg,
1169 			  hx509_cert cert,
1170 			  hx509_peer_info peer,
1171 			  hx509_certs anchors,
1172 			  hx509_certs pool,
1173 			  heim_octet_string *signed_data)
1174 {
1175     hx509_certs certs;
1176     int ret = 0;
1177 
1178     signed_data->data = NULL;
1179     signed_data->length = 0;
1180 
1181     ret = hx509_certs_init(context, "MEMORY:certs", 0, NULL, &certs);
1182     if (ret)
1183 	return ret;
1184     ret = hx509_certs_add(context, certs, cert);
1185     if (ret)
1186 	goto out;
1187 
1188     ret = hx509_cms_create_signed(context, flags, eContentType, data, length,
1189 				  digest_alg, certs, peer, anchors, pool,
1190 				  signed_data);
1191 
1192  out:
1193     hx509_certs_free(&certs);
1194     return ret;
1195 }
1196 
1197 struct sigctx {
1198     SignedData sd;
1199     const AlgorithmIdentifier *digest_alg;
1200     const heim_oid *eContentType;
1201     heim_octet_string content;
1202     hx509_peer_info peer;
1203     int cmsidflag;
1204     int leafonly;
1205     hx509_certs certs;
1206     hx509_certs anchors;
1207     hx509_certs pool;
1208 };
1209 
1210 static int
sig_process(hx509_context context,void * ctx,hx509_cert cert)1211 sig_process(hx509_context context, void *ctx, hx509_cert cert)
1212 {
1213     struct sigctx *sigctx = ctx;
1214     heim_octet_string buf, sigdata = { 0, NULL };
1215     SignerInfo *signer_info = NULL;
1216     AlgorithmIdentifier digest;
1217     size_t size;
1218     void *ptr;
1219     int ret;
1220     SignedData *sd = &sigctx->sd;
1221     hx509_path path;
1222 
1223     memset(&digest, 0, sizeof(digest));
1224     memset(&path, 0, sizeof(path));
1225 
1226     if (_hx509_cert_private_key(cert) == NULL) {
1227 	hx509_set_error_string(context, 0, HX509_PRIVATE_KEY_MISSING,
1228 			       "Private key missing for signing");
1229 	return HX509_PRIVATE_KEY_MISSING;
1230     }
1231 
1232     if (sigctx->digest_alg) {
1233 	ret = copy_AlgorithmIdentifier(sigctx->digest_alg, &digest);
1234 	if (ret)
1235 	    hx509_clear_error_string(context);
1236     } else {
1237 	ret = hx509_crypto_select(context, HX509_SELECT_DIGEST,
1238 				  _hx509_cert_private_key(cert),
1239 				  sigctx->peer, &digest);
1240     }
1241     if (ret)
1242 	goto out;
1243 
1244     /*
1245      * Allocate on more signerInfo and do the signature processing
1246      */
1247 
1248     ptr = realloc(sd->signerInfos.val,
1249 		  (sd->signerInfos.len + 1) * sizeof(sd->signerInfos.val[0]));
1250     if (ptr == NULL) {
1251 	ret = ENOMEM;
1252 	goto out;
1253     }
1254     sd->signerInfos.val = ptr;
1255 
1256     signer_info = &sd->signerInfos.val[sd->signerInfos.len];
1257 
1258     memset(signer_info, 0, sizeof(*signer_info));
1259 
1260     signer_info->version = 1;
1261 
1262     ret = fill_CMSIdentifier(cert, sigctx->cmsidflag, &signer_info->sid);
1263     if (ret) {
1264 	hx509_clear_error_string(context);
1265 	goto out;
1266     }
1267 
1268     signer_info->signedAttrs = NULL;
1269     signer_info->unsignedAttrs = NULL;
1270 
1271     ret = copy_AlgorithmIdentifier(&digest, &signer_info->digestAlgorithm);
1272     if (ret) {
1273 	hx509_clear_error_string(context);
1274 	goto out;
1275     }
1276 
1277     /*
1278      * If it isn't pkcs7-data send signedAttributes
1279      */
1280 
1281     if (der_heim_oid_cmp(sigctx->eContentType, &asn1_oid_id_pkcs7_data) != 0) {
1282 	CMSAttributes sa;
1283 	heim_octet_string sig;
1284 
1285 	ALLOC(signer_info->signedAttrs, 1);
1286 	if (signer_info->signedAttrs == NULL) {
1287 	    ret = ENOMEM;
1288 	    goto out;
1289 	}
1290 
1291 	ret = _hx509_create_signature(context,
1292 				      NULL,
1293 				      &digest,
1294 				      &sigctx->content,
1295 				      NULL,
1296 				      &sig);
1297 	if (ret)
1298 	    goto out;
1299 
1300 	ASN1_MALLOC_ENCODE(MessageDigest,
1301 			   buf.data,
1302 			   buf.length,
1303 			   &sig,
1304 			   &size,
1305 			   ret);
1306 	der_free_octet_string(&sig);
1307 	if (ret) {
1308 	    hx509_clear_error_string(context);
1309 	    goto out;
1310 	}
1311 	if (size != buf.length)
1312 	    _hx509_abort("internal ASN.1 encoder error");
1313 
1314 	ret = add_one_attribute(&signer_info->signedAttrs->val,
1315 				&signer_info->signedAttrs->len,
1316 				&asn1_oid_id_pkcs9_messageDigest,
1317 				&buf);
1318 	if (ret) {
1319 	    free(buf.data);
1320 	    hx509_clear_error_string(context);
1321 	    goto out;
1322 	}
1323 
1324 
1325 	ASN1_MALLOC_ENCODE(ContentType,
1326 			   buf.data,
1327 			   buf.length,
1328 			   sigctx->eContentType,
1329 			   &size,
1330 			   ret);
1331 	if (ret)
1332 	    goto out;
1333 	if (size != buf.length)
1334 	    _hx509_abort("internal ASN.1 encoder error");
1335 
1336 	ret = add_one_attribute(&signer_info->signedAttrs->val,
1337 				&signer_info->signedAttrs->len,
1338 				&asn1_oid_id_pkcs9_contentType,
1339 				&buf);
1340 	if (ret) {
1341 	    free(buf.data);
1342 	    hx509_clear_error_string(context);
1343 	    goto out;
1344 	}
1345 
1346 	sa.val = signer_info->signedAttrs->val;
1347 	sa.len = signer_info->signedAttrs->len;
1348 
1349 	ASN1_MALLOC_ENCODE(CMSAttributes,
1350 			   sigdata.data,
1351 			   sigdata.length,
1352 			   &sa,
1353 			   &size,
1354 			   ret);
1355 	if (ret) {
1356 	    hx509_clear_error_string(context);
1357 	    goto out;
1358 	}
1359 	if (size != sigdata.length)
1360 	    _hx509_abort("internal ASN.1 encoder error");
1361     } else {
1362 	sigdata.data = sigctx->content.data;
1363 	sigdata.length = sigctx->content.length;
1364     }
1365 
1366     {
1367 	AlgorithmIdentifier sigalg;
1368 
1369 	ret = hx509_crypto_select(context, HX509_SELECT_PUBLIC_SIG,
1370 				  _hx509_cert_private_key(cert), sigctx->peer,
1371 				  &sigalg);
1372 	if (ret)
1373 	    goto out;
1374 
1375 	ret = _hx509_create_signature(context,
1376 				      _hx509_cert_private_key(cert),
1377 				      &sigalg,
1378 				      &sigdata,
1379 				      &signer_info->signatureAlgorithm,
1380 				      &signer_info->signature);
1381 	free_AlgorithmIdentifier(&sigalg);
1382 	if (ret)
1383 	    goto out;
1384     }
1385 
1386     sigctx->sd.signerInfos.len++;
1387     signer_info = NULL;
1388 
1389     /*
1390      * Provide best effort path
1391      */
1392     if (sigctx->certs) {
1393 	unsigned int i;
1394 
1395 	if (sigctx->pool && sigctx->leafonly == 0) {
1396 	    _hx509_calculate_path(context,
1397 				  HX509_CALCULATE_PATH_NO_ANCHOR,
1398 				  time(NULL),
1399 				  sigctx->anchors,
1400 				  0,
1401 				  cert,
1402 				  sigctx->pool,
1403 				  &path);
1404 	} else
1405 	    _hx509_path_append(context, &path, cert);
1406 
1407 	for (i = 0; i < path.len; i++) {
1408 	    /* XXX remove dups */
1409 	    ret = hx509_certs_add(context, sigctx->certs, path.val[i]);
1410 	    if (ret) {
1411 		hx509_clear_error_string(context);
1412 		goto out;
1413 	    }
1414 	}
1415     }
1416 
1417  out:
1418     if (signer_info)
1419 	free_SignerInfo(signer_info);
1420     if (sigdata.data != sigctx->content.data)
1421 	der_free_octet_string(&sigdata);
1422     _hx509_path_free(&path);
1423     free_AlgorithmIdentifier(&digest);
1424 
1425     return ret;
1426 }
1427 
1428 static int
cert_process(hx509_context context,void * ctx,hx509_cert cert)1429 cert_process(hx509_context context, void *ctx, hx509_cert cert)
1430 {
1431     struct sigctx *sigctx = ctx;
1432     const unsigned int i = sigctx->sd.certificates->len;
1433     void *ptr;
1434     int ret;
1435 
1436     ptr = realloc(sigctx->sd.certificates->val,
1437 		  (i + 1) * sizeof(sigctx->sd.certificates->val[0]));
1438     if (ptr == NULL)
1439 	return ENOMEM;
1440     sigctx->sd.certificates->val = ptr;
1441 
1442     ret = hx509_cert_binary(context, cert,
1443 			    &sigctx->sd.certificates->val[i]);
1444     if (ret == 0)
1445 	sigctx->sd.certificates->len++;
1446 
1447     return ret;
1448 }
1449 
1450 static int
cmp_AlgorithmIdentifier(const AlgorithmIdentifier * p,const AlgorithmIdentifier * q)1451 cmp_AlgorithmIdentifier(const AlgorithmIdentifier *p, const AlgorithmIdentifier *q)
1452 {
1453     return der_heim_oid_cmp(&p->algorithm, &q->algorithm);
1454 }
1455 
1456 int
hx509_cms_create_signed(hx509_context context,int flags,const heim_oid * eContentType,const void * data,size_t length,const AlgorithmIdentifier * digest_alg,hx509_certs certs,hx509_peer_info peer,hx509_certs anchors,hx509_certs pool,heim_octet_string * signed_data)1457 hx509_cms_create_signed(hx509_context context,
1458 			int flags,
1459 			const heim_oid *eContentType,
1460 			const void *data, size_t length,
1461 			const AlgorithmIdentifier *digest_alg,
1462 			hx509_certs certs,
1463 			hx509_peer_info peer,
1464 			hx509_certs anchors,
1465 			hx509_certs pool,
1466 			heim_octet_string *signed_data)
1467 {
1468     unsigned int i, j;
1469     hx509_name name;
1470     int ret;
1471     size_t size;
1472     struct sigctx sigctx;
1473 
1474     memset(&sigctx, 0, sizeof(sigctx));
1475     memset(&name, 0, sizeof(name));
1476 
1477     if (eContentType == NULL)
1478 	eContentType = &asn1_oid_id_pkcs7_data;
1479 
1480     sigctx.digest_alg = digest_alg;
1481     sigctx.content.data = rk_UNCONST(data);
1482     sigctx.content.length = length;
1483     sigctx.eContentType = eContentType;
1484     sigctx.peer = peer;
1485     /**
1486      * Use HX509_CMS_SIGNATURE_ID_NAME to preferred use of issuer name
1487      * and serial number if possible. Otherwise subject key identifier
1488      * will preferred.
1489      */
1490     if (flags & HX509_CMS_SIGNATURE_ID_NAME)
1491 	sigctx.cmsidflag = CMS_ID_NAME;
1492     else
1493 	sigctx.cmsidflag = CMS_ID_SKI;
1494 
1495     /**
1496      * Use HX509_CMS_SIGNATURE_LEAF_ONLY to only request leaf
1497      * certificates to be added to the SignedData.
1498      */
1499     sigctx.leafonly = (flags & HX509_CMS_SIGNATURE_LEAF_ONLY) ? 1 : 0;
1500 
1501     /**
1502      * Use HX509_CMS_NO_CERTS to make the SignedData contain no
1503      * certificates, overrides HX509_CMS_SIGNATURE_LEAF_ONLY.
1504      */
1505 
1506     if ((flags & HX509_CMS_SIGNATURE_NO_CERTS) == 0) {
1507 	ret = hx509_certs_init(context, "MEMORY:certs", 0, NULL, &sigctx.certs);
1508 	if (ret)
1509 	    return ret;
1510     }
1511 
1512     sigctx.anchors = anchors;
1513     sigctx.pool = pool;
1514 
1515     sigctx.sd.version = CMSVersion_v3;
1516 
1517     der_copy_oid(eContentType, &sigctx.sd.encapContentInfo.eContentType);
1518 
1519     /**
1520      * Use HX509_CMS_SIGNATURE_DETACHED to create detached signatures.
1521      */
1522     if ((flags & HX509_CMS_SIGNATURE_DETACHED) == 0) {
1523 	ALLOC(sigctx.sd.encapContentInfo.eContent, 1);
1524 	if (sigctx.sd.encapContentInfo.eContent == NULL) {
1525 	    hx509_clear_error_string(context);
1526 	    ret = ENOMEM;
1527 	    goto out;
1528 	}
1529 
1530 	sigctx.sd.encapContentInfo.eContent->data = malloc(length);
1531 	if (sigctx.sd.encapContentInfo.eContent->data == NULL) {
1532 	    hx509_clear_error_string(context);
1533 	    ret = ENOMEM;
1534 	    goto out;
1535 	}
1536 	memcpy(sigctx.sd.encapContentInfo.eContent->data, data, length);
1537 	sigctx.sd.encapContentInfo.eContent->length = length;
1538     }
1539 
1540     /**
1541      * Use HX509_CMS_SIGNATURE_NO_SIGNER to create no sigInfo (no
1542      * signatures).
1543      */
1544     if ((flags & HX509_CMS_SIGNATURE_NO_SIGNER) == 0) {
1545 	ret = hx509_certs_iter_f(context, certs, sig_process, &sigctx);
1546 	if (ret)
1547 	    goto out;
1548     }
1549 
1550     if (sigctx.sd.signerInfos.len) {
1551 
1552 	/*
1553 	 * For each signerInfo, collect all different digest types.
1554 	 */
1555 	for (i = 0; i < sigctx.sd.signerInfos.len; i++) {
1556 	    AlgorithmIdentifier *di =
1557 		&sigctx.sd.signerInfos.val[i].digestAlgorithm;
1558 
1559 	    for (j = 0; j < sigctx.sd.digestAlgorithms.len; j++)
1560 		if (cmp_AlgorithmIdentifier(di, &sigctx.sd.digestAlgorithms.val[j]) == 0)
1561 		    break;
1562 	    if (j == sigctx.sd.digestAlgorithms.len) {
1563 		ret = add_DigestAlgorithmIdentifiers(&sigctx.sd.digestAlgorithms, di);
1564 		if (ret) {
1565 		    hx509_clear_error_string(context);
1566 		    goto out;
1567 		}
1568 	    }
1569 	}
1570     }
1571 
1572     /*
1573      * Add certs we think are needed, build as part of sig_process
1574      */
1575     if (sigctx.certs) {
1576 	ALLOC(sigctx.sd.certificates, 1);
1577 	if (sigctx.sd.certificates == NULL) {
1578 	    hx509_clear_error_string(context);
1579 	    ret = ENOMEM;
1580 	    goto out;
1581 	}
1582 
1583 	ret = hx509_certs_iter_f(context, sigctx.certs, cert_process, &sigctx);
1584 	if (ret)
1585 	    goto out;
1586     }
1587 
1588     ASN1_MALLOC_ENCODE(SignedData,
1589 		       signed_data->data, signed_data->length,
1590 		       &sigctx.sd, &size, ret);
1591     if (ret) {
1592 	hx509_clear_error_string(context);
1593 	goto out;
1594     }
1595     if (signed_data->length != size)
1596 	_hx509_abort("internal ASN.1 encoder error");
1597 
1598 out:
1599     hx509_certs_free(&sigctx.certs);
1600     free_SignedData(&sigctx.sd);
1601 
1602     return ret;
1603 }
1604 
1605 int
hx509_cms_decrypt_encrypted(hx509_context context,hx509_lock lock,const void * data,size_t length,heim_oid * contentType,heim_octet_string * content)1606 hx509_cms_decrypt_encrypted(hx509_context context,
1607 			    hx509_lock lock,
1608 			    const void *data,
1609 			    size_t length,
1610 			    heim_oid *contentType,
1611 			    heim_octet_string *content)
1612 {
1613     heim_octet_string cont;
1614     CMSEncryptedData ed;
1615     AlgorithmIdentifier *ai;
1616     int ret;
1617 
1618     memset(content, 0, sizeof(*content));
1619     memset(&cont, 0, sizeof(cont));
1620 
1621     ret = decode_CMSEncryptedData(data, length, &ed, NULL);
1622     if (ret) {
1623 	hx509_set_error_string(context, 0, ret,
1624 			       "Failed to decode CMSEncryptedData");
1625 	return ret;
1626     }
1627 
1628     if (ed.encryptedContentInfo.encryptedContent == NULL) {
1629 	ret = HX509_CMS_NO_DATA_AVAILABLE;
1630 	hx509_set_error_string(context, 0, ret,
1631 			       "No content in EncryptedData");
1632 	goto out;
1633     }
1634 
1635     ret = der_copy_oid(&ed.encryptedContentInfo.contentType, contentType);
1636     if (ret) {
1637 	hx509_clear_error_string(context);
1638 	goto out;
1639     }
1640 
1641     ai = &ed.encryptedContentInfo.contentEncryptionAlgorithm;
1642     if (ai->parameters == NULL) {
1643 	ret = HX509_ALG_NOT_SUPP;
1644 	hx509_clear_error_string(context);
1645 	goto out;
1646     }
1647 
1648     ret = _hx509_pbe_decrypt(context,
1649 			     lock,
1650 			     ai,
1651 			     ed.encryptedContentInfo.encryptedContent,
1652 			     &cont);
1653     if (ret)
1654 	goto out;
1655 
1656     *content = cont;
1657 
1658 out:
1659     if (ret) {
1660 	if (cont.data)
1661 	    free(cont.data);
1662     }
1663     free_CMSEncryptedData(&ed);
1664     return ret;
1665 }
1666