1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* PKCS#7 parser
3 *
4 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8 #define pr_fmt(fmt) "PKCS7: "fmt
9 #ifdef __UBOOT__
10 #include <log.h>
11 #include <dm/devres.h>
12 #include <linux/bitops.h>
13 #include <linux/compat.h>
14 #endif
15 #include <linux/kernel.h>
16 #ifndef __UBOOT__
17 #include <linux/module.h>
18 #include <linux/export.h>
19 #include <linux/slab.h>
20 #endif
21 #include <linux/err.h>
22 #include <linux/oid_registry.h>
23 #include <crypto/public_key.h>
24 #ifdef __UBOOT__
25 #include <crypto/pkcs7_parser.h>
26 #else
27 #include "pkcs7_parser.h"
28 #endif
29 #include "pkcs7.asn1.h"
30
31 MODULE_DESCRIPTION("PKCS#7 parser");
32 MODULE_AUTHOR("Red Hat, Inc.");
33 MODULE_LICENSE("GPL");
34
35 struct pkcs7_parse_context {
36 struct pkcs7_message *msg; /* Message being constructed */
37 struct pkcs7_signed_info *sinfo; /* SignedInfo being constructed */
38 struct pkcs7_signed_info **ppsinfo;
39 struct x509_certificate *certs; /* Certificate cache */
40 struct x509_certificate **ppcerts;
41 unsigned long data; /* Start of data */
42 enum OID last_oid; /* Last OID encountered */
43 unsigned x509_index;
44 unsigned sinfo_index;
45 const void *raw_serial;
46 unsigned raw_serial_size;
47 unsigned raw_issuer_size;
48 const void *raw_issuer;
49 const void *raw_skid;
50 unsigned raw_skid_size;
51 bool expect_skid;
52 };
53
54 /*
55 * Free a signed information block.
56 */
pkcs7_free_signed_info(struct pkcs7_signed_info * sinfo)57 static void pkcs7_free_signed_info(struct pkcs7_signed_info *sinfo)
58 {
59 if (sinfo) {
60 public_key_signature_free(sinfo->sig);
61 kfree(sinfo);
62 }
63 }
64
65 /**
66 * pkcs7_free_message - Free a PKCS#7 message
67 * @pkcs7: The PKCS#7 message to free
68 */
pkcs7_free_message(struct pkcs7_message * pkcs7)69 void pkcs7_free_message(struct pkcs7_message *pkcs7)
70 {
71 struct x509_certificate *cert;
72 struct pkcs7_signed_info *sinfo;
73
74 if (pkcs7) {
75 while (pkcs7->certs) {
76 cert = pkcs7->certs;
77 pkcs7->certs = cert->next;
78 x509_free_certificate(cert);
79 }
80 while (pkcs7->crl) {
81 cert = pkcs7->crl;
82 pkcs7->crl = cert->next;
83 x509_free_certificate(cert);
84 }
85 while (pkcs7->signed_infos) {
86 sinfo = pkcs7->signed_infos;
87 pkcs7->signed_infos = sinfo->next;
88 pkcs7_free_signed_info(sinfo);
89 }
90 kfree(pkcs7);
91 }
92 }
93 EXPORT_SYMBOL_GPL(pkcs7_free_message);
94
95 /*
96 * Check authenticatedAttributes are provided or not provided consistently.
97 */
pkcs7_check_authattrs(struct pkcs7_message * msg)98 static int pkcs7_check_authattrs(struct pkcs7_message *msg)
99 {
100 struct pkcs7_signed_info *sinfo;
101 bool want = false;
102
103 sinfo = msg->signed_infos;
104 if (!sinfo)
105 goto inconsistent;
106
107 if (sinfo->authattrs) {
108 want = true;
109 msg->have_authattrs = true;
110 }
111
112 for (sinfo = sinfo->next; sinfo; sinfo = sinfo->next)
113 if (!!sinfo->authattrs != want)
114 goto inconsistent;
115 return 0;
116
117 inconsistent:
118 pr_warn("Inconsistently supplied authAttrs\n");
119 return -EINVAL;
120 }
121
122 /**
123 * pkcs7_parse_message - Parse a PKCS#7 message
124 * @data: The raw binary ASN.1 encoded message to be parsed
125 * @datalen: The size of the encoded message
126 */
pkcs7_parse_message(const void * data,size_t datalen)127 struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen)
128 {
129 struct pkcs7_parse_context *ctx;
130 struct pkcs7_message *msg = ERR_PTR(-ENOMEM);
131 int ret;
132
133 ctx = kzalloc(sizeof(struct pkcs7_parse_context), GFP_KERNEL);
134 if (!ctx)
135 goto out_no_ctx;
136 ctx->msg = kzalloc(sizeof(struct pkcs7_message), GFP_KERNEL);
137 if (!ctx->msg)
138 goto out_no_msg;
139 ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
140 if (!ctx->sinfo)
141 goto out_no_sinfo;
142 ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
143 GFP_KERNEL);
144 if (!ctx->sinfo->sig)
145 goto out_no_sig;
146
147 ctx->data = (unsigned long)data;
148 ctx->ppcerts = &ctx->certs;
149 ctx->ppsinfo = &ctx->msg->signed_infos;
150
151 /* Attempt to decode the signature */
152 ret = asn1_ber_decoder(&pkcs7_decoder, ctx, data, datalen);
153 if (ret < 0) {
154 msg = ERR_PTR(ret);
155 goto out;
156 }
157
158 ret = pkcs7_check_authattrs(ctx->msg);
159 if (ret < 0) {
160 msg = ERR_PTR(ret);
161 goto out;
162 }
163
164 msg = ctx->msg;
165 ctx->msg = NULL;
166
167 out:
168 while (ctx->certs) {
169 struct x509_certificate *cert = ctx->certs;
170 ctx->certs = cert->next;
171 x509_free_certificate(cert);
172 }
173 out_no_sig:
174 pkcs7_free_signed_info(ctx->sinfo);
175 out_no_sinfo:
176 pkcs7_free_message(ctx->msg);
177 out_no_msg:
178 kfree(ctx);
179 out_no_ctx:
180 return msg;
181 }
182 EXPORT_SYMBOL_GPL(pkcs7_parse_message);
183
184 /**
185 * pkcs7_get_content_data - Get access to the PKCS#7 content
186 * @pkcs7: The preparsed PKCS#7 message to access
187 * @_data: Place to return a pointer to the data
188 * @_data_len: Place to return the data length
189 * @_headerlen: Size of ASN.1 header not included in _data
190 *
191 * Get access to the data content of the PKCS#7 message. The size of the
192 * header of the ASN.1 object that contains it is also provided and can be used
193 * to adjust *_data and *_data_len to get the entire object.
194 *
195 * Returns -ENODATA if the data object was missing from the message.
196 */
pkcs7_get_content_data(const struct pkcs7_message * pkcs7,const void ** _data,size_t * _data_len,size_t * _headerlen)197 int pkcs7_get_content_data(const struct pkcs7_message *pkcs7,
198 const void **_data, size_t *_data_len,
199 size_t *_headerlen)
200 {
201 if (!pkcs7->data)
202 return -ENODATA;
203
204 *_data = pkcs7->data;
205 *_data_len = pkcs7->data_len;
206 if (_headerlen)
207 *_headerlen = pkcs7->data_hdrlen;
208 return 0;
209 }
210 EXPORT_SYMBOL_GPL(pkcs7_get_content_data);
211
212 /*
213 * Note an OID when we find one for later processing when we know how
214 * to interpret it.
215 */
pkcs7_note_OID(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)216 int pkcs7_note_OID(void *context, size_t hdrlen,
217 unsigned char tag,
218 const void *value, size_t vlen)
219 {
220 struct pkcs7_parse_context *ctx = context;
221
222 ctx->last_oid = look_up_OID(value, vlen);
223 if (ctx->last_oid == OID__NR) {
224 char buffer[50];
225 sprint_oid(value, vlen, buffer, sizeof(buffer));
226 printk("PKCS7: Unknown OID: [%lu] %s\n",
227 (unsigned long)value - ctx->data, buffer);
228 }
229 return 0;
230 }
231
232 /*
233 * Note the digest algorithm for the signature.
234 */
pkcs7_sig_note_digest_algo(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)235 int pkcs7_sig_note_digest_algo(void *context, size_t hdrlen,
236 unsigned char tag,
237 const void *value, size_t vlen)
238 {
239 struct pkcs7_parse_context *ctx = context;
240
241 switch (ctx->last_oid) {
242 case OID_md4:
243 ctx->sinfo->sig->hash_algo = "md4";
244 break;
245 case OID_md5:
246 ctx->sinfo->sig->hash_algo = "md5";
247 break;
248 case OID_sha1:
249 ctx->sinfo->sig->hash_algo = "sha1";
250 break;
251 case OID_sha256:
252 ctx->sinfo->sig->hash_algo = "sha256";
253 break;
254 case OID_sha384:
255 ctx->sinfo->sig->hash_algo = "sha384";
256 break;
257 case OID_sha512:
258 ctx->sinfo->sig->hash_algo = "sha512";
259 break;
260 case OID_sha224:
261 ctx->sinfo->sig->hash_algo = "sha224";
262 break;
263 default:
264 printk("Unsupported digest algo: %u\n", ctx->last_oid);
265 return -ENOPKG;
266 }
267 return 0;
268 }
269
270 /*
271 * Note the public key algorithm for the signature.
272 */
pkcs7_sig_note_pkey_algo(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)273 int pkcs7_sig_note_pkey_algo(void *context, size_t hdrlen,
274 unsigned char tag,
275 const void *value, size_t vlen)
276 {
277 struct pkcs7_parse_context *ctx = context;
278
279 switch (ctx->last_oid) {
280 case OID_rsaEncryption:
281 ctx->sinfo->sig->pkey_algo = "rsa";
282 ctx->sinfo->sig->encoding = "pkcs1";
283 break;
284 default:
285 printk("Unsupported pkey algo: %u\n", ctx->last_oid);
286 return -ENOPKG;
287 }
288 return 0;
289 }
290
291 /*
292 * We only support signed data [RFC2315 sec 9].
293 */
pkcs7_check_content_type(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)294 int pkcs7_check_content_type(void *context, size_t hdrlen,
295 unsigned char tag,
296 const void *value, size_t vlen)
297 {
298 struct pkcs7_parse_context *ctx = context;
299
300 if (ctx->last_oid != OID_signed_data) {
301 pr_warn("Only support pkcs7_signedData type\n");
302 return -EINVAL;
303 }
304
305 return 0;
306 }
307
308 /*
309 * Note the SignedData version
310 */
pkcs7_note_signeddata_version(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)311 int pkcs7_note_signeddata_version(void *context, size_t hdrlen,
312 unsigned char tag,
313 const void *value, size_t vlen)
314 {
315 struct pkcs7_parse_context *ctx = context;
316 unsigned version;
317
318 if (vlen != 1)
319 goto unsupported;
320
321 ctx->msg->version = version = *(const u8 *)value;
322 switch (version) {
323 case 1:
324 /* PKCS#7 SignedData [RFC2315 sec 9.1]
325 * CMS ver 1 SignedData [RFC5652 sec 5.1]
326 */
327 break;
328 case 3:
329 /* CMS ver 3 SignedData [RFC2315 sec 5.1] */
330 break;
331 default:
332 goto unsupported;
333 }
334
335 return 0;
336
337 unsupported:
338 pr_warn("Unsupported SignedData version\n");
339 return -EINVAL;
340 }
341
342 /*
343 * Note the SignerInfo version
344 */
pkcs7_note_signerinfo_version(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)345 int pkcs7_note_signerinfo_version(void *context, size_t hdrlen,
346 unsigned char tag,
347 const void *value, size_t vlen)
348 {
349 struct pkcs7_parse_context *ctx = context;
350 unsigned version;
351
352 if (vlen != 1)
353 goto unsupported;
354
355 version = *(const u8 *)value;
356 switch (version) {
357 case 1:
358 /* PKCS#7 SignerInfo [RFC2315 sec 9.2]
359 * CMS ver 1 SignerInfo [RFC5652 sec 5.3]
360 */
361 if (ctx->msg->version != 1)
362 goto version_mismatch;
363 ctx->expect_skid = false;
364 break;
365 case 3:
366 /* CMS ver 3 SignerInfo [RFC2315 sec 5.3] */
367 if (ctx->msg->version == 1)
368 goto version_mismatch;
369 ctx->expect_skid = true;
370 break;
371 default:
372 goto unsupported;
373 }
374
375 return 0;
376
377 unsupported:
378 pr_warn("Unsupported SignerInfo version\n");
379 return -EINVAL;
380 version_mismatch:
381 pr_warn("SignedData-SignerInfo version mismatch\n");
382 return -EBADMSG;
383 }
384
385 /*
386 * Extract a certificate and store it in the context.
387 */
pkcs7_extract_cert(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)388 int pkcs7_extract_cert(void *context, size_t hdrlen,
389 unsigned char tag,
390 const void *value, size_t vlen)
391 {
392 struct pkcs7_parse_context *ctx = context;
393 struct x509_certificate *x509;
394
395 if (tag != ((ASN1_UNIV << 6) | ASN1_CONS_BIT | ASN1_SEQ)) {
396 pr_debug("Cert began with tag %02x at %lu\n",
397 tag, (unsigned long)ctx - ctx->data);
398 return -EBADMSG;
399 }
400
401 /* We have to correct for the header so that the X.509 parser can start
402 * from the beginning. Note that since X.509 stipulates DER, there
403 * probably shouldn't be an EOC trailer - but it is in PKCS#7 (which
404 * stipulates BER).
405 */
406 value -= hdrlen;
407 vlen += hdrlen;
408
409 if (((u8*)value)[1] == 0x80)
410 vlen += 2; /* Indefinite length - there should be an EOC */
411
412 x509 = x509_cert_parse(value, vlen);
413 if (IS_ERR(x509))
414 return PTR_ERR(x509);
415
416 x509->index = ++ctx->x509_index;
417 pr_debug("Got cert %u for %s\n", x509->index, x509->subject);
418 pr_debug("- fingerprint %*phN\n", x509->id->len, x509->id->data);
419
420 *ctx->ppcerts = x509;
421 ctx->ppcerts = &x509->next;
422 return 0;
423 }
424
425 /*
426 * Save the certificate list
427 */
pkcs7_note_certificate_list(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)428 int pkcs7_note_certificate_list(void *context, size_t hdrlen,
429 unsigned char tag,
430 const void *value, size_t vlen)
431 {
432 struct pkcs7_parse_context *ctx = context;
433
434 pr_devel("Got cert list (%02x)\n", tag);
435
436 *ctx->ppcerts = ctx->msg->certs;
437 ctx->msg->certs = ctx->certs;
438 ctx->certs = NULL;
439 ctx->ppcerts = &ctx->certs;
440 return 0;
441 }
442
443 /*
444 * Note the content type.
445 */
pkcs7_note_content(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)446 int pkcs7_note_content(void *context, size_t hdrlen,
447 unsigned char tag,
448 const void *value, size_t vlen)
449 {
450 struct pkcs7_parse_context *ctx = context;
451
452 if (ctx->last_oid != OID_data &&
453 ctx->last_oid != OID_msIndirectData) {
454 pr_warn("Unsupported data type %d\n", ctx->last_oid);
455 return -EINVAL;
456 }
457
458 ctx->msg->data_type = ctx->last_oid;
459 return 0;
460 }
461
462 /*
463 * Extract the data from the message and store that and its content type OID in
464 * the context.
465 */
pkcs7_note_data(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)466 int pkcs7_note_data(void *context, size_t hdrlen,
467 unsigned char tag,
468 const void *value, size_t vlen)
469 {
470 struct pkcs7_parse_context *ctx = context;
471
472 pr_debug("Got data\n");
473
474 ctx->msg->data = value;
475 ctx->msg->data_len = vlen;
476 ctx->msg->data_hdrlen = hdrlen;
477 return 0;
478 }
479
480 /*
481 * Parse authenticated attributes.
482 */
pkcs7_sig_note_authenticated_attr(void * context,size_t hdrlen,unsigned char tag,const void * value,size_t vlen)483 int pkcs7_sig_note_authenticated_attr(void *context, size_t hdrlen,
484 unsigned char tag,
485 const void *value, size_t vlen)
486 {
487 struct pkcs7_parse_context *ctx = context;
488 struct pkcs7_signed_info *sinfo = ctx->sinfo;
489 enum OID content_type;
490
491 pr_devel("AuthAttr: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
492
493 switch (ctx->last_oid) {
494 case OID_contentType:
495 if (__test_and_set_bit(sinfo_has_content_type, &sinfo->aa_set))
496 goto repeated;
497 content_type = look_up_OID(value, vlen);
498 if (content_type != ctx->msg->data_type) {
499 pr_warn("Mismatch between global data type (%d) and sinfo %u (%d)\n",
500 ctx->msg->data_type, sinfo->index,
501 content_type);
502 return -EBADMSG;
503 }
504 return 0;
505
506 case OID_signingTime:
507 if (__test_and_set_bit(sinfo_has_signing_time, &sinfo->aa_set))
508 goto repeated;
509 /* Should we check that the signing time is consistent
510 * with the signer's X.509 cert?
511 */
512 return x509_decode_time(&sinfo->signing_time,
513 hdrlen, tag, value, vlen);
514
515 case OID_messageDigest:
516 if (__test_and_set_bit(sinfo_has_message_digest, &sinfo->aa_set))
517 goto repeated;
518 if (tag != ASN1_OTS)
519 return -EBADMSG;
520 sinfo->msgdigest = value;
521 sinfo->msgdigest_len = vlen;
522 return 0;
523
524 case OID_smimeCapabilites:
525 if (__test_and_set_bit(sinfo_has_smime_caps, &sinfo->aa_set))
526 goto repeated;
527 #ifdef __UBOOT__ /* OID_data is needed for authenticated UEFI variables */
528 if (ctx->msg->data_type != OID_msIndirectData &&
529 ctx->msg->data_type != OID_data) {
530 #else
531 if (ctx->msg->data_type != OID_msIndirectData) {
532 #endif
533 pr_warn("S/MIME Caps only allowed with Authenticode\n");
534 return -EKEYREJECTED;
535 }
536 return 0;
537
538 /* Microsoft SpOpusInfo seems to be contain cont[0] 16-bit BE
539 * char URLs and cont[1] 8-bit char URLs.
540 *
541 * Microsoft StatementType seems to contain a list of OIDs that
542 * are also used as extendedKeyUsage types in X.509 certs.
543 */
544 case OID_msSpOpusInfo:
545 if (__test_and_set_bit(sinfo_has_ms_opus_info, &sinfo->aa_set))
546 goto repeated;
547 goto authenticode_check;
548 case OID_msStatementType:
549 if (__test_and_set_bit(sinfo_has_ms_statement_type, &sinfo->aa_set))
550 goto repeated;
551 authenticode_check:
552 if (ctx->msg->data_type != OID_msIndirectData) {
553 pr_warn("Authenticode AuthAttrs only allowed with Authenticode\n");
554 return -EKEYREJECTED;
555 }
556 /* I'm not sure how to validate these */
557 return 0;
558 default:
559 return 0;
560 }
561
562 repeated:
563 /* We permit max one item per AuthenticatedAttribute and no repeats */
564 pr_warn("Repeated/multivalue AuthAttrs not permitted\n");
565 return -EKEYREJECTED;
566 }
567
568 /*
569 * Note the set of auth attributes for digestion purposes [RFC2315 sec 9.3]
570 */
571 int pkcs7_sig_note_set_of_authattrs(void *context, size_t hdrlen,
572 unsigned char tag,
573 const void *value, size_t vlen)
574 {
575 struct pkcs7_parse_context *ctx = context;
576 struct pkcs7_signed_info *sinfo = ctx->sinfo;
577
578 if (!test_bit(sinfo_has_content_type, &sinfo->aa_set) ||
579 !test_bit(sinfo_has_message_digest, &sinfo->aa_set)) {
580 pr_warn("Missing required AuthAttr\n");
581 return -EBADMSG;
582 }
583
584 if (ctx->msg->data_type != OID_msIndirectData &&
585 test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) {
586 pr_warn("Unexpected Authenticode AuthAttr\n");
587 return -EBADMSG;
588 }
589
590 /* We need to switch the 'CONT 0' to a 'SET OF' when we digest */
591 sinfo->authattrs = value - (hdrlen - 1);
592 sinfo->authattrs_len = vlen + (hdrlen - 1);
593 return 0;
594 }
595
596 /*
597 * Note the issuing certificate serial number
598 */
599 int pkcs7_sig_note_serial(void *context, size_t hdrlen,
600 unsigned char tag,
601 const void *value, size_t vlen)
602 {
603 struct pkcs7_parse_context *ctx = context;
604 ctx->raw_serial = value;
605 ctx->raw_serial_size = vlen;
606 return 0;
607 }
608
609 /*
610 * Note the issuer's name
611 */
612 int pkcs7_sig_note_issuer(void *context, size_t hdrlen,
613 unsigned char tag,
614 const void *value, size_t vlen)
615 {
616 struct pkcs7_parse_context *ctx = context;
617 ctx->raw_issuer = value;
618 ctx->raw_issuer_size = vlen;
619 return 0;
620 }
621
622 /*
623 * Note the issuing cert's subjectKeyIdentifier
624 */
625 int pkcs7_sig_note_skid(void *context, size_t hdrlen,
626 unsigned char tag,
627 const void *value, size_t vlen)
628 {
629 struct pkcs7_parse_context *ctx = context;
630
631 pr_devel("SKID: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
632
633 ctx->raw_skid = value;
634 ctx->raw_skid_size = vlen;
635 return 0;
636 }
637
638 /*
639 * Note the signature data
640 */
641 int pkcs7_sig_note_signature(void *context, size_t hdrlen,
642 unsigned char tag,
643 const void *value, size_t vlen)
644 {
645 struct pkcs7_parse_context *ctx = context;
646
647 ctx->sinfo->sig->s = kmemdup(value, vlen, GFP_KERNEL);
648 if (!ctx->sinfo->sig->s)
649 return -ENOMEM;
650
651 ctx->sinfo->sig->s_size = vlen;
652 return 0;
653 }
654
655 /*
656 * Note a signature information block
657 */
658 int pkcs7_note_signed_info(void *context, size_t hdrlen,
659 unsigned char tag,
660 const void *value, size_t vlen)
661 {
662 struct pkcs7_parse_context *ctx = context;
663 struct pkcs7_signed_info *sinfo = ctx->sinfo;
664 struct asymmetric_key_id *kid;
665
666 if (ctx->msg->data_type == OID_msIndirectData && !sinfo->authattrs) {
667 pr_warn("Authenticode requires AuthAttrs\n");
668 return -EBADMSG;
669 }
670
671 /* Generate cert issuer + serial number key ID */
672 if (!ctx->expect_skid) {
673 kid = asymmetric_key_generate_id(ctx->raw_serial,
674 ctx->raw_serial_size,
675 ctx->raw_issuer,
676 ctx->raw_issuer_size);
677 } else {
678 kid = asymmetric_key_generate_id(ctx->raw_skid,
679 ctx->raw_skid_size,
680 "", 0);
681 }
682 if (IS_ERR(kid))
683 return PTR_ERR(kid);
684
685 pr_devel("SINFO KID: %u [%*phN]\n", kid->len, kid->len, kid->data);
686
687 sinfo->sig->auth_ids[0] = kid;
688 sinfo->index = ++ctx->sinfo_index;
689 *ctx->ppsinfo = sinfo;
690 ctx->ppsinfo = &sinfo->next;
691 ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
692 if (!ctx->sinfo)
693 return -ENOMEM;
694 ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
695 GFP_KERNEL);
696 if (!ctx->sinfo->sig)
697 return -ENOMEM;
698 return 0;
699 }
700