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 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/export.h>
12 #include <linux/slab.h>
13 #include <linux/err.h>
14 #include <linux/oid_registry.h>
15 #include <crypto/public_key.h>
16 #include "pkcs7_parser.h"
17 #include "pkcs7.asn1.h"
18 
19 MODULE_DESCRIPTION("PKCS#7 parser");
20 MODULE_AUTHOR("Red Hat, Inc.");
21 MODULE_LICENSE("GPL");
22 
23 struct pkcs7_parse_context {
24 	struct pkcs7_message	*msg;		/* Message being constructed */
25 	struct pkcs7_signed_info *sinfo;	/* SignedInfo being constructed */
26 	struct pkcs7_signed_info **ppsinfo;
27 	struct x509_certificate *certs;		/* Certificate cache */
28 	struct x509_certificate **ppcerts;
29 	unsigned long	data;			/* Start of data */
30 	enum OID	last_oid;		/* Last OID encountered */
31 	unsigned	x509_index;
32 	unsigned	sinfo_index;
33 	const void	*raw_serial;
34 	unsigned	raw_serial_size;
35 	unsigned	raw_issuer_size;
36 	const void	*raw_issuer;
37 	const void	*raw_skid;
38 	unsigned	raw_skid_size;
39 	bool		expect_skid;
40 };
41 
42 /*
43  * Free a signed information block.
44  */
45 static void pkcs7_free_signed_info(struct pkcs7_signed_info *sinfo)
46 {
47 	if (sinfo) {
48 		public_key_signature_free(sinfo->sig);
49 		kfree(sinfo);
50 	}
51 }
52 
53 /**
54  * pkcs7_free_message - Free a PKCS#7 message
55  * @pkcs7: The PKCS#7 message to free
56  */
57 void pkcs7_free_message(struct pkcs7_message *pkcs7)
58 {
59 	struct x509_certificate *cert;
60 	struct pkcs7_signed_info *sinfo;
61 
62 	if (pkcs7) {
63 		while (pkcs7->certs) {
64 			cert = pkcs7->certs;
65 			pkcs7->certs = cert->next;
66 			x509_free_certificate(cert);
67 		}
68 		while (pkcs7->crl) {
69 			cert = pkcs7->crl;
70 			pkcs7->crl = cert->next;
71 			x509_free_certificate(cert);
72 		}
73 		while (pkcs7->signed_infos) {
74 			sinfo = pkcs7->signed_infos;
75 			pkcs7->signed_infos = sinfo->next;
76 			pkcs7_free_signed_info(sinfo);
77 		}
78 		kfree(pkcs7);
79 	}
80 }
81 EXPORT_SYMBOL_GPL(pkcs7_free_message);
82 
83 /*
84  * Check authenticatedAttributes are provided or not provided consistently.
85  */
86 static int pkcs7_check_authattrs(struct pkcs7_message *msg)
87 {
88 	struct pkcs7_signed_info *sinfo;
89 	bool want = false;
90 
91 	sinfo = msg->signed_infos;
92 	if (!sinfo)
93 		goto inconsistent;
94 
95 	if (sinfo->authattrs) {
96 		want = true;
97 		msg->have_authattrs = true;
98 	}
99 
100 	for (sinfo = sinfo->next; sinfo; sinfo = sinfo->next)
101 		if (!!sinfo->authattrs != want)
102 			goto inconsistent;
103 	return 0;
104 
105 inconsistent:
106 	pr_warn("Inconsistently supplied authAttrs\n");
107 	return -EINVAL;
108 }
109 
110 /**
111  * pkcs7_parse_message - Parse a PKCS#7 message
112  * @data: The raw binary ASN.1 encoded message to be parsed
113  * @datalen: The size of the encoded message
114  */
115 struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen)
116 {
117 	struct pkcs7_parse_context *ctx;
118 	struct pkcs7_message *msg = ERR_PTR(-ENOMEM);
119 	int ret;
120 
121 	ctx = kzalloc(sizeof(struct pkcs7_parse_context), GFP_KERNEL);
122 	if (!ctx)
123 		goto out_no_ctx;
124 	ctx->msg = kzalloc(sizeof(struct pkcs7_message), GFP_KERNEL);
125 	if (!ctx->msg)
126 		goto out_no_msg;
127 	ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
128 	if (!ctx->sinfo)
129 		goto out_no_sinfo;
130 	ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
131 				  GFP_KERNEL);
132 	if (!ctx->sinfo->sig)
133 		goto out_no_sig;
134 
135 	ctx->data = (unsigned long)data;
136 	ctx->ppcerts = &ctx->certs;
137 	ctx->ppsinfo = &ctx->msg->signed_infos;
138 
139 	/* Attempt to decode the signature */
140 	ret = asn1_ber_decoder(&pkcs7_decoder, ctx, data, datalen);
141 	if (ret < 0) {
142 		msg = ERR_PTR(ret);
143 		goto out;
144 	}
145 
146 	ret = pkcs7_check_authattrs(ctx->msg);
147 	if (ret < 0) {
148 		msg = ERR_PTR(ret);
149 		goto out;
150 	}
151 
152 	msg = ctx->msg;
153 	ctx->msg = NULL;
154 
155 out:
156 	while (ctx->certs) {
157 		struct x509_certificate *cert = ctx->certs;
158 		ctx->certs = cert->next;
159 		x509_free_certificate(cert);
160 	}
161 out_no_sig:
162 	pkcs7_free_signed_info(ctx->sinfo);
163 out_no_sinfo:
164 	pkcs7_free_message(ctx->msg);
165 out_no_msg:
166 	kfree(ctx);
167 out_no_ctx:
168 	return msg;
169 }
170 EXPORT_SYMBOL_GPL(pkcs7_parse_message);
171 
172 /**
173  * pkcs7_get_content_data - Get access to the PKCS#7 content
174  * @pkcs7: The preparsed PKCS#7 message to access
175  * @_data: Place to return a pointer to the data
176  * @_data_len: Place to return the data length
177  * @_headerlen: Size of ASN.1 header not included in _data
178  *
179  * Get access to the data content of the PKCS#7 message.  The size of the
180  * header of the ASN.1 object that contains it is also provided and can be used
181  * to adjust *_data and *_data_len to get the entire object.
182  *
183  * Returns -ENODATA if the data object was missing from the message.
184  */
185 int pkcs7_get_content_data(const struct pkcs7_message *pkcs7,
186 			   const void **_data, size_t *_data_len,
187 			   size_t *_headerlen)
188 {
189 	if (!pkcs7->data)
190 		return -ENODATA;
191 
192 	*_data = pkcs7->data;
193 	*_data_len = pkcs7->data_len;
194 	if (_headerlen)
195 		*_headerlen = pkcs7->data_hdrlen;
196 	return 0;
197 }
198 EXPORT_SYMBOL_GPL(pkcs7_get_content_data);
199 
200 /*
201  * Note an OID when we find one for later processing when we know how
202  * to interpret it.
203  */
204 int pkcs7_note_OID(void *context, size_t hdrlen,
205 		   unsigned char tag,
206 		   const void *value, size_t vlen)
207 {
208 	struct pkcs7_parse_context *ctx = context;
209 
210 	ctx->last_oid = look_up_OID(value, vlen);
211 	if (ctx->last_oid == OID__NR) {
212 		char buffer[50];
213 		sprint_oid(value, vlen, buffer, sizeof(buffer));
214 		printk("PKCS7: Unknown OID: [%lu] %s\n",
215 		       (unsigned long)value - ctx->data, buffer);
216 	}
217 	return 0;
218 }
219 
220 /*
221  * Note the digest algorithm for the signature.
222  */
223 int pkcs7_sig_note_digest_algo(void *context, size_t hdrlen,
224 			       unsigned char tag,
225 			       const void *value, size_t vlen)
226 {
227 	struct pkcs7_parse_context *ctx = context;
228 
229 	switch (ctx->last_oid) {
230 	case OID_md4:
231 		ctx->sinfo->sig->hash_algo = "md4";
232 		break;
233 	case OID_md5:
234 		ctx->sinfo->sig->hash_algo = "md5";
235 		break;
236 	case OID_sha1:
237 		ctx->sinfo->sig->hash_algo = "sha1";
238 		break;
239 	case OID_sha256:
240 		ctx->sinfo->sig->hash_algo = "sha256";
241 		break;
242 	case OID_sha384:
243 		ctx->sinfo->sig->hash_algo = "sha384";
244 		break;
245 	case OID_sha512:
246 		ctx->sinfo->sig->hash_algo = "sha512";
247 		break;
248 	case OID_sha224:
249 		ctx->sinfo->sig->hash_algo = "sha224";
250 		break;
251 	case OID_sm3:
252 		ctx->sinfo->sig->hash_algo = "sm3";
253 		break;
254 	case OID_gost2012Digest256:
255 		ctx->sinfo->sig->hash_algo = "streebog256";
256 		break;
257 	case OID_gost2012Digest512:
258 		ctx->sinfo->sig->hash_algo = "streebog512";
259 		break;
260 	default:
261 		printk("Unsupported digest algo: %u\n", ctx->last_oid);
262 		return -ENOPKG;
263 	}
264 	return 0;
265 }
266 
267 /*
268  * Note the public key algorithm for the signature.
269  */
270 int pkcs7_sig_note_pkey_algo(void *context, size_t hdrlen,
271 			     unsigned char tag,
272 			     const void *value, size_t vlen)
273 {
274 	struct pkcs7_parse_context *ctx = context;
275 
276 	switch (ctx->last_oid) {
277 	case OID_rsaEncryption:
278 		ctx->sinfo->sig->pkey_algo = "rsa";
279 		ctx->sinfo->sig->encoding = "pkcs1";
280 		break;
281 	case OID_id_ecdsa_with_sha1:
282 	case OID_id_ecdsa_with_sha224:
283 	case OID_id_ecdsa_with_sha256:
284 	case OID_id_ecdsa_with_sha384:
285 	case OID_id_ecdsa_with_sha512:
286 		ctx->sinfo->sig->pkey_algo = "ecdsa";
287 		ctx->sinfo->sig->encoding = "x962";
288 		break;
289 	case OID_SM2_with_SM3:
290 		ctx->sinfo->sig->pkey_algo = "sm2";
291 		ctx->sinfo->sig->encoding = "raw";
292 		break;
293 	case OID_gost2012PKey256:
294 	case OID_gost2012PKey512:
295 		ctx->sinfo->sig->pkey_algo = "ecrdsa";
296 		ctx->sinfo->sig->encoding = "raw";
297 		break;
298 	default:
299 		printk("Unsupported pkey algo: %u\n", ctx->last_oid);
300 		return -ENOPKG;
301 	}
302 	return 0;
303 }
304 
305 /*
306  * We only support signed data [RFC2315 sec 9].
307  */
308 int pkcs7_check_content_type(void *context, size_t hdrlen,
309 			     unsigned char tag,
310 			     const void *value, size_t vlen)
311 {
312 	struct pkcs7_parse_context *ctx = context;
313 
314 	if (ctx->last_oid != OID_signed_data) {
315 		pr_warn("Only support pkcs7_signedData type\n");
316 		return -EINVAL;
317 	}
318 
319 	return 0;
320 }
321 
322 /*
323  * Note the SignedData version
324  */
325 int pkcs7_note_signeddata_version(void *context, size_t hdrlen,
326 				  unsigned char tag,
327 				  const void *value, size_t vlen)
328 {
329 	struct pkcs7_parse_context *ctx = context;
330 	unsigned version;
331 
332 	if (vlen != 1)
333 		goto unsupported;
334 
335 	ctx->msg->version = version = *(const u8 *)value;
336 	switch (version) {
337 	case 1:
338 		/* PKCS#7 SignedData [RFC2315 sec 9.1]
339 		 * CMS ver 1 SignedData [RFC5652 sec 5.1]
340 		 */
341 		break;
342 	case 3:
343 		/* CMS ver 3 SignedData [RFC2315 sec 5.1] */
344 		break;
345 	default:
346 		goto unsupported;
347 	}
348 
349 	return 0;
350 
351 unsupported:
352 	pr_warn("Unsupported SignedData version\n");
353 	return -EINVAL;
354 }
355 
356 /*
357  * Note the SignerInfo version
358  */
359 int pkcs7_note_signerinfo_version(void *context, size_t hdrlen,
360 				  unsigned char tag,
361 				  const void *value, size_t vlen)
362 {
363 	struct pkcs7_parse_context *ctx = context;
364 	unsigned version;
365 
366 	if (vlen != 1)
367 		goto unsupported;
368 
369 	version = *(const u8 *)value;
370 	switch (version) {
371 	case 1:
372 		/* PKCS#7 SignerInfo [RFC2315 sec 9.2]
373 		 * CMS ver 1 SignerInfo [RFC5652 sec 5.3]
374 		 */
375 		if (ctx->msg->version != 1)
376 			goto version_mismatch;
377 		ctx->expect_skid = false;
378 		break;
379 	case 3:
380 		/* CMS ver 3 SignerInfo [RFC2315 sec 5.3] */
381 		if (ctx->msg->version == 1)
382 			goto version_mismatch;
383 		ctx->expect_skid = true;
384 		break;
385 	default:
386 		goto unsupported;
387 	}
388 
389 	return 0;
390 
391 unsupported:
392 	pr_warn("Unsupported SignerInfo version\n");
393 	return -EINVAL;
394 version_mismatch:
395 	pr_warn("SignedData-SignerInfo version mismatch\n");
396 	return -EBADMSG;
397 }
398 
399 /*
400  * Extract a certificate and store it in the context.
401  */
402 int pkcs7_extract_cert(void *context, size_t hdrlen,
403 		       unsigned char tag,
404 		       const void *value, size_t vlen)
405 {
406 	struct pkcs7_parse_context *ctx = context;
407 	struct x509_certificate *x509;
408 
409 	if (tag != ((ASN1_UNIV << 6) | ASN1_CONS_BIT | ASN1_SEQ)) {
410 		pr_debug("Cert began with tag %02x at %lu\n",
411 			 tag, (unsigned long)ctx - ctx->data);
412 		return -EBADMSG;
413 	}
414 
415 	/* We have to correct for the header so that the X.509 parser can start
416 	 * from the beginning.  Note that since X.509 stipulates DER, there
417 	 * probably shouldn't be an EOC trailer - but it is in PKCS#7 (which
418 	 * stipulates BER).
419 	 */
420 	value -= hdrlen;
421 	vlen += hdrlen;
422 
423 	if (((u8*)value)[1] == 0x80)
424 		vlen += 2; /* Indefinite length - there should be an EOC */
425 
426 	x509 = x509_cert_parse(value, vlen);
427 	if (IS_ERR(x509))
428 		return PTR_ERR(x509);
429 
430 	x509->index = ++ctx->x509_index;
431 	pr_debug("Got cert %u for %s\n", x509->index, x509->subject);
432 	pr_debug("- fingerprint %*phN\n", x509->id->len, x509->id->data);
433 
434 	*ctx->ppcerts = x509;
435 	ctx->ppcerts = &x509->next;
436 	return 0;
437 }
438 
439 /*
440  * Save the certificate list
441  */
442 int pkcs7_note_certificate_list(void *context, size_t hdrlen,
443 				unsigned char tag,
444 				const void *value, size_t vlen)
445 {
446 	struct pkcs7_parse_context *ctx = context;
447 
448 	pr_devel("Got cert list (%02x)\n", tag);
449 
450 	*ctx->ppcerts = ctx->msg->certs;
451 	ctx->msg->certs = ctx->certs;
452 	ctx->certs = NULL;
453 	ctx->ppcerts = &ctx->certs;
454 	return 0;
455 }
456 
457 /*
458  * Note the content type.
459  */
460 int pkcs7_note_content(void *context, size_t hdrlen,
461 		       unsigned char tag,
462 		       const void *value, size_t vlen)
463 {
464 	struct pkcs7_parse_context *ctx = context;
465 
466 	if (ctx->last_oid != OID_data &&
467 	    ctx->last_oid != OID_msIndirectData) {
468 		pr_warn("Unsupported data type %d\n", ctx->last_oid);
469 		return -EINVAL;
470 	}
471 
472 	ctx->msg->data_type = ctx->last_oid;
473 	return 0;
474 }
475 
476 /*
477  * Extract the data from the message and store that and its content type OID in
478  * the context.
479  */
480 int pkcs7_note_data(void *context, size_t hdrlen,
481 		    unsigned char tag,
482 		    const void *value, size_t vlen)
483 {
484 	struct pkcs7_parse_context *ctx = context;
485 
486 	pr_debug("Got data\n");
487 
488 	ctx->msg->data = value;
489 	ctx->msg->data_len = vlen;
490 	ctx->msg->data_hdrlen = hdrlen;
491 	return 0;
492 }
493 
494 /*
495  * Parse authenticated attributes.
496  */
497 int pkcs7_sig_note_authenticated_attr(void *context, size_t hdrlen,
498 				      unsigned char tag,
499 				      const void *value, size_t vlen)
500 {
501 	struct pkcs7_parse_context *ctx = context;
502 	struct pkcs7_signed_info *sinfo = ctx->sinfo;
503 	enum OID content_type;
504 
505 	pr_devel("AuthAttr: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
506 
507 	switch (ctx->last_oid) {
508 	case OID_contentType:
509 		if (__test_and_set_bit(sinfo_has_content_type, &sinfo->aa_set))
510 			goto repeated;
511 		content_type = look_up_OID(value, vlen);
512 		if (content_type != ctx->msg->data_type) {
513 			pr_warn("Mismatch between global data type (%d) and sinfo %u (%d)\n",
514 				ctx->msg->data_type, sinfo->index,
515 				content_type);
516 			return -EBADMSG;
517 		}
518 		return 0;
519 
520 	case OID_signingTime:
521 		if (__test_and_set_bit(sinfo_has_signing_time, &sinfo->aa_set))
522 			goto repeated;
523 		/* Should we check that the signing time is consistent
524 		 * with the signer's X.509 cert?
525 		 */
526 		return x509_decode_time(&sinfo->signing_time,
527 					hdrlen, tag, value, vlen);
528 
529 	case OID_messageDigest:
530 		if (__test_and_set_bit(sinfo_has_message_digest, &sinfo->aa_set))
531 			goto repeated;
532 		if (tag != ASN1_OTS)
533 			return -EBADMSG;
534 		sinfo->msgdigest = value;
535 		sinfo->msgdigest_len = vlen;
536 		return 0;
537 
538 	case OID_smimeCapabilites:
539 		if (__test_and_set_bit(sinfo_has_smime_caps, &sinfo->aa_set))
540 			goto repeated;
541 		if (ctx->msg->data_type != OID_msIndirectData) {
542 			pr_warn("S/MIME Caps only allowed with Authenticode\n");
543 			return -EKEYREJECTED;
544 		}
545 		return 0;
546 
547 		/* Microsoft SpOpusInfo seems to be contain cont[0] 16-bit BE
548 		 * char URLs and cont[1] 8-bit char URLs.
549 		 *
550 		 * Microsoft StatementType seems to contain a list of OIDs that
551 		 * are also used as extendedKeyUsage types in X.509 certs.
552 		 */
553 	case OID_msSpOpusInfo:
554 		if (__test_and_set_bit(sinfo_has_ms_opus_info, &sinfo->aa_set))
555 			goto repeated;
556 		goto authenticode_check;
557 	case OID_msStatementType:
558 		if (__test_and_set_bit(sinfo_has_ms_statement_type, &sinfo->aa_set))
559 			goto repeated;
560 	authenticode_check:
561 		if (ctx->msg->data_type != OID_msIndirectData) {
562 			pr_warn("Authenticode AuthAttrs only allowed with Authenticode\n");
563 			return -EKEYREJECTED;
564 		}
565 		/* I'm not sure how to validate these */
566 		return 0;
567 	default:
568 		return 0;
569 	}
570 
571 repeated:
572 	/* We permit max one item per AuthenticatedAttribute and no repeats */
573 	pr_warn("Repeated/multivalue AuthAttrs not permitted\n");
574 	return -EKEYREJECTED;
575 }
576 
577 /*
578  * Note the set of auth attributes for digestion purposes [RFC2315 sec 9.3]
579  */
580 int pkcs7_sig_note_set_of_authattrs(void *context, size_t hdrlen,
581 				    unsigned char tag,
582 				    const void *value, size_t vlen)
583 {
584 	struct pkcs7_parse_context *ctx = context;
585 	struct pkcs7_signed_info *sinfo = ctx->sinfo;
586 
587 	if (!test_bit(sinfo_has_content_type, &sinfo->aa_set) ||
588 	    !test_bit(sinfo_has_message_digest, &sinfo->aa_set)) {
589 		pr_warn("Missing required AuthAttr\n");
590 		return -EBADMSG;
591 	}
592 
593 	if (ctx->msg->data_type != OID_msIndirectData &&
594 	    test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) {
595 		pr_warn("Unexpected Authenticode AuthAttr\n");
596 		return -EBADMSG;
597 	}
598 
599 	/* We need to switch the 'CONT 0' to a 'SET OF' when we digest */
600 	sinfo->authattrs = value - (hdrlen - 1);
601 	sinfo->authattrs_len = vlen + (hdrlen - 1);
602 	return 0;
603 }
604 
605 /*
606  * Note the issuing certificate serial number
607  */
608 int pkcs7_sig_note_serial(void *context, size_t hdrlen,
609 			  unsigned char tag,
610 			  const void *value, size_t vlen)
611 {
612 	struct pkcs7_parse_context *ctx = context;
613 	ctx->raw_serial = value;
614 	ctx->raw_serial_size = vlen;
615 	return 0;
616 }
617 
618 /*
619  * Note the issuer's name
620  */
621 int pkcs7_sig_note_issuer(void *context, size_t hdrlen,
622 			  unsigned char tag,
623 			  const void *value, size_t vlen)
624 {
625 	struct pkcs7_parse_context *ctx = context;
626 	ctx->raw_issuer = value;
627 	ctx->raw_issuer_size = vlen;
628 	return 0;
629 }
630 
631 /*
632  * Note the issuing cert's subjectKeyIdentifier
633  */
634 int pkcs7_sig_note_skid(void *context, size_t hdrlen,
635 			unsigned char tag,
636 			const void *value, size_t vlen)
637 {
638 	struct pkcs7_parse_context *ctx = context;
639 
640 	pr_devel("SKID: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
641 
642 	ctx->raw_skid = value;
643 	ctx->raw_skid_size = vlen;
644 	return 0;
645 }
646 
647 /*
648  * Note the signature data
649  */
650 int pkcs7_sig_note_signature(void *context, size_t hdrlen,
651 			     unsigned char tag,
652 			     const void *value, size_t vlen)
653 {
654 	struct pkcs7_parse_context *ctx = context;
655 
656 	ctx->sinfo->sig->s = kmemdup(value, vlen, GFP_KERNEL);
657 	if (!ctx->sinfo->sig->s)
658 		return -ENOMEM;
659 
660 	ctx->sinfo->sig->s_size = vlen;
661 	return 0;
662 }
663 
664 /*
665  * Note a signature information block
666  */
667 int pkcs7_note_signed_info(void *context, size_t hdrlen,
668 			   unsigned char tag,
669 			   const void *value, size_t vlen)
670 {
671 	struct pkcs7_parse_context *ctx = context;
672 	struct pkcs7_signed_info *sinfo = ctx->sinfo;
673 	struct asymmetric_key_id *kid;
674 
675 	if (ctx->msg->data_type == OID_msIndirectData && !sinfo->authattrs) {
676 		pr_warn("Authenticode requires AuthAttrs\n");
677 		return -EBADMSG;
678 	}
679 
680 	/* Generate cert issuer + serial number key ID */
681 	if (!ctx->expect_skid) {
682 		kid = asymmetric_key_generate_id(ctx->raw_serial,
683 						 ctx->raw_serial_size,
684 						 ctx->raw_issuer,
685 						 ctx->raw_issuer_size);
686 	} else {
687 		kid = asymmetric_key_generate_id(ctx->raw_skid,
688 						 ctx->raw_skid_size,
689 						 "", 0);
690 	}
691 	if (IS_ERR(kid))
692 		return PTR_ERR(kid);
693 
694 	pr_devel("SINFO KID: %u [%*phN]\n", kid->len, kid->len, kid->data);
695 
696 	sinfo->sig->auth_ids[0] = kid;
697 	sinfo->index = ++ctx->sinfo_index;
698 	*ctx->ppsinfo = sinfo;
699 	ctx->ppsinfo = &sinfo->next;
700 	ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
701 	if (!ctx->sinfo)
702 		return -ENOMEM;
703 	ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
704 				  GFP_KERNEL);
705 	if (!ctx->sinfo->sig)
706 		return -ENOMEM;
707 	return 0;
708 }
709