crypto/asymmetric_keys/pkcs7_parser.c

   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_sha1:
 231                 ctx->sinfo->sig->hash_algo = "sha1";
 232                 break;
 233         case OID_sha256:
 234                 ctx->sinfo->sig->hash_algo = "sha256";
 235                 break;
 236         case OID_sha384:
 237                 ctx->sinfo->sig->hash_algo = "sha384";
 238                 break;
 239         case OID_sha512:
 240                 ctx->sinfo->sig->hash_algo = "sha512";
 241                 break;
 242         case OID_sha224:
 243                 ctx->sinfo->sig->hash_algo = "sha224";
 244                 break;
 245         case OID_sm3:
 246                 ctx->sinfo->sig->hash_algo = "sm3";
 247                 break;
 248         case OID_gost2012Digest256:
 249                 ctx->sinfo->sig->hash_algo = "streebog256";
 250                 break;
 251         case OID_gost2012Digest512:
 252                 ctx->sinfo->sig->hash_algo = "streebog512";
 253                 break;
 254         case OID_sha3_256:
 255                 ctx->sinfo->sig->hash_algo = "sha3-256";
 256                 break;
 257         case OID_sha3_384:
 258                 ctx->sinfo->sig->hash_algo = "sha3-384";
 259                 break;
 260         case OID_sha3_512:
 261                 ctx->sinfo->sig->hash_algo = "sha3-512";
 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  */
 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         case OID_id_ecdsa_with_sha1:
 285         case OID_id_ecdsa_with_sha224:
 286         case OID_id_ecdsa_with_sha256:
 287         case OID_id_ecdsa_with_sha384:
 288         case OID_id_ecdsa_with_sha512:
 289         case OID_id_ecdsa_with_sha3_256:
 290         case OID_id_ecdsa_with_sha3_384:
 291         case OID_id_ecdsa_with_sha3_512:
 292                 ctx->sinfo->sig->pkey_algo = "ecdsa";
 293                 ctx->sinfo->sig->encoding = "x962";
 294                 break;
 295         case OID_gost2012PKey256:
 296         case OID_gost2012PKey512:
 297                 ctx->sinfo->sig->pkey_algo = "ecrdsa";
 298                 ctx->sinfo->sig->encoding = "raw";
 299                 break;
 300         default:
 301                 printk("Unsupported pkey algo: %u\n", ctx->last_oid);
 302                 return -ENOPKG;
 303         }
 304         return 0;
 305 }
 306
 307 /*
 308  * We only support signed data [RFC2315 sec 9].
 309  */
 310 int pkcs7_check_content_type(void *context, size_t hdrlen,
 311                              unsigned char tag,
 312                              const void *value, size_t vlen)
 313 {
 314         struct pkcs7_parse_context *ctx = context;
 315
 316         if (ctx->last_oid != OID_signed_data) {
 317                 pr_warn("Only support pkcs7_signedData type\n");
 318                 return -EINVAL;
 319         }
 320
 321         return 0;
 322 }
 323
 324 /*
 325  * Note the SignedData version
 326  */
 327 int pkcs7_note_signeddata_version(void *context, size_t hdrlen,
 328                                   unsigned char tag,
 329                                   const void *value, size_t vlen)
 330 {
 331         struct pkcs7_parse_context *ctx = context;
 332         unsigned version;
 333
 334         if (vlen != 1)
 335                 goto unsupported;
 336
 337         ctx->msg->version = version = *(const u8 *)value;
 338         switch (version) {
 339         case 1:
 340                 /* PKCS#7 SignedData [RFC2315 sec 9.1]
 341                  * CMS ver 1 SignedData [RFC5652 sec 5.1]
 342                  */
 343                 break;
 344         case 3:
 345                 /* CMS ver 3 SignedData [RFC2315 sec 5.1] */
 346                 break;
 347         default:
 348                 goto unsupported;
 349         }
 350
 351         return 0;
 352
 353 unsupported:
 354         pr_warn("Unsupported SignedData version\n");
 355         return -EINVAL;
 356 }
 357
 358 /*
 359  * Note the SignerInfo version
 360  */
 361 int pkcs7_note_signerinfo_version(void *context, size_t hdrlen,
 362                                   unsigned char tag,
 363                                   const void *value, size_t vlen)
 364 {
 365         struct pkcs7_parse_context *ctx = context;
 366         unsigned version;
 367
 368         if (vlen != 1)
 369                 goto unsupported;
 370
 371         version = *(const u8 *)value;
 372         switch (version) {
 373         case 1:
 374                 /* PKCS#7 SignerInfo [RFC2315 sec 9.2]
 375                  * CMS ver 1 SignerInfo [RFC5652 sec 5.3]
 376                  */
 377                 if (ctx->msg->version != 1)
 378                         goto version_mismatch;
 379                 ctx->expect_skid = false;
 380                 break;
 381         case 3:
 382                 /* CMS ver 3 SignerInfo [RFC2315 sec 5.3] */
 383                 if (ctx->msg->version == 1)
 384                         goto version_mismatch;
 385                 ctx->expect_skid = true;
 386                 break;
 387         default:
 388                 goto unsupported;
 389         }
 390
 391         return 0;
 392
 393 unsupported:
 394         pr_warn("Unsupported SignerInfo version\n");
 395         return -EINVAL;
 396 version_mismatch:
 397         pr_warn("SignedData-SignerInfo version mismatch\n");
 398         return -EBADMSG;
 399 }
 400
 401 /*
 402  * Extract a certificate and store it in the context.
 403  */
 404 int pkcs7_extract_cert(void *context, size_t hdrlen,
 405                        unsigned char tag,
 406                        const void *value, size_t vlen)
 407 {
 408         struct pkcs7_parse_context *ctx = context;
 409         struct x509_certificate *x509;
 410
 411         if (tag != ((ASN1_UNIV << 6) | ASN1_CONS_BIT | ASN1_SEQ)) {
 412                 pr_debug("Cert began with tag %02x at %lu\n",
 413                          tag, (unsigned long)ctx - ctx->data);
 414                 return -EBADMSG;
 415         }
 416
 417         /* We have to correct for the header so that the X.509 parser can start
 418          * from the beginning.  Note that since X.509 stipulates DER, there
 419          * probably shouldn't be an EOC trailer - but it is in PKCS#7 (which
 420          * stipulates BER).
 421          */
 422         value -= hdrlen;
 423         vlen += hdrlen;
 424
 425         if (((u8*)value)[1] == 0x80)
 426                 vlen += 2; /* Indefinite length - there should be an EOC */
 427
 428         x509 = x509_cert_parse(value, vlen);
 429         if (IS_ERR(x509))
 430                 return PTR_ERR(x509);
 431
 432         x509->index = ++ctx->x509_index;
 433         pr_debug("Got cert %u for %s\n", x509->index, x509->subject);
 434         pr_debug("- fingerprint %*phN\n", x509->id->len, x509->id->data);
 435
 436         *ctx->ppcerts = x509;
 437         ctx->ppcerts = &x509->next;
 438         return 0;
 439 }
 440
 441 /*
 442  * Save the certificate list
 443  */
 444 int pkcs7_note_certificate_list(void *context, size_t hdrlen,
 445                                 unsigned char tag,
 446                                 const void *value, size_t vlen)
 447 {
 448         struct pkcs7_parse_context *ctx = context;
 449
 450         pr_devel("Got cert list (%02x)\n", tag);
 451
 452         *ctx->ppcerts = ctx->msg->certs;
 453         ctx->msg->certs = ctx->certs;
 454         ctx->certs = NULL;
 455         ctx->ppcerts = &ctx->certs;
 456         return 0;
 457 }
 458
 459 /*
 460  * Note the content type.
 461  */
 462 int pkcs7_note_content(void *context, size_t hdrlen,
 463                        unsigned char tag,
 464                        const void *value, size_t vlen)
 465 {
 466         struct pkcs7_parse_context *ctx = context;
 467
 468         if (ctx->last_oid != OID_data &&
 469             ctx->last_oid != OID_msIndirectData) {
 470                 pr_warn("Unsupported data type %d\n", ctx->last_oid);
 471                 return -EINVAL;
 472         }
 473
 474         ctx->msg->data_type = ctx->last_oid;
 475         return 0;
 476 }
 477
 478 /*
 479  * Extract the data from the message and store that and its content type OID in
 480  * the context.
 481  */
 482 int pkcs7_note_data(void *context, size_t hdrlen,
 483                     unsigned char tag,
 484                     const void *value, size_t vlen)
 485 {
 486         struct pkcs7_parse_context *ctx = context;
 487
 488         pr_debug("Got data\n");
 489
 490         ctx->msg->data = value;
 491         ctx->msg->data_len = vlen;
 492         ctx->msg->data_hdrlen = hdrlen;
 493         return 0;
 494 }
 495
 496 /*
 497  * Parse authenticated attributes.
 498  */
 499 int pkcs7_sig_note_authenticated_attr(void *context, size_t hdrlen,
 500                                       unsigned char tag,
 501                                       const void *value, size_t vlen)
 502 {
 503         struct pkcs7_parse_context *ctx = context;
 504         struct pkcs7_signed_info *sinfo = ctx->sinfo;
 505         enum OID content_type;
 506
 507         pr_devel("AuthAttr: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
 508
 509         switch (ctx->last_oid) {
 510         case OID_contentType:
 511                 if (__test_and_set_bit(sinfo_has_content_type, &sinfo->aa_set))
 512                         goto repeated;
 513                 content_type = look_up_OID(value, vlen);
 514                 if (content_type != ctx->msg->data_type) {
 515                         pr_warn("Mismatch between global data type (%d) and sinfo %u (%d)\n",
 516                                 ctx->msg->data_type, sinfo->index,
 517                                 content_type);
 518                         return -EBADMSG;
 519                 }
 520                 return 0;
 521
 522         case OID_signingTime:
 523                 if (__test_and_set_bit(sinfo_has_signing_time, &sinfo->aa_set))
 524                         goto repeated;
 525                 /* Should we check that the signing time is consistent
 526                  * with the signer's X.509 cert?
 527                  */
 528                 return x509_decode_time(&sinfo->signing_time,
 529                                         hdrlen, tag, value, vlen);
 530
 531         case OID_messageDigest:
 532                 if (__test_and_set_bit(sinfo_has_message_digest, &sinfo->aa_set))
 533                         goto repeated;
 534                 if (tag != ASN1_OTS)
 535                         return -EBADMSG;
 536                 sinfo->msgdigest = value;
 537                 sinfo->msgdigest_len = vlen;
 538                 return 0;
 539
 540         case OID_smimeCapabilites:
 541                 if (__test_and_set_bit(sinfo_has_smime_caps, &sinfo->aa_set))
 542                         goto repeated;
 543                 if (ctx->msg->data_type != OID_msIndirectData) {
 544                         pr_warn("S/MIME Caps only allowed with Authenticode\n");
 545                         return -EKEYREJECTED;
 546                 }
 547                 return 0;
 548
 549                 /* Microsoft SpOpusInfo seems to be contain cont[0] 16-bit BE
 550                  * char URLs and cont[1] 8-bit char URLs.
 551                  *
 552                  * Microsoft StatementType seems to contain a list of OIDs that
 553                  * are also used as extendedKeyUsage types in X.509 certs.
 554                  */
 555         case OID_msSpOpusInfo:
 556                 if (__test_and_set_bit(sinfo_has_ms_opus_info, &sinfo->aa_set))
 557                         goto repeated;
 558                 goto authenticode_check;
 559         case OID_msStatementType:
 560                 if (__test_and_set_bit(sinfo_has_ms_statement_type, &sinfo->aa_set))
 561                         goto repeated;
 562         authenticode_check:
 563                 if (ctx->msg->data_type != OID_msIndirectData) {
 564                         pr_warn("Authenticode AuthAttrs only allowed with Authenticode\n");
 565                         return -EKEYREJECTED;
 566                 }
 567                 /* I'm not sure how to validate these */
 568                 return 0;
 569         default:
 570                 return 0;
 571         }
 572
 573 repeated:
 574         /* We permit max one item per AuthenticatedAttribute and no repeats */
 575         pr_warn("Repeated/multivalue AuthAttrs not permitted\n");
 576         return -EKEYREJECTED;
 577 }
 578
 579 /*
 580  * Note the set of auth attributes for digestion purposes [RFC2315 sec 9.3]
 581  */
 582 int pkcs7_sig_note_set_of_authattrs(void *context, size_t hdrlen,
 583                                     unsigned char tag,
 584                                     const void *value, size_t vlen)
 585 {
 586         struct pkcs7_parse_context *ctx = context;
 587         struct pkcs7_signed_info *sinfo = ctx->sinfo;
 588
 589         if (!test_bit(sinfo_has_content_type, &sinfo->aa_set) ||
 590             !test_bit(sinfo_has_message_digest, &sinfo->aa_set)) {
 591                 pr_warn("Missing required AuthAttr\n");
 592                 return -EBADMSG;
 593         }
 594
 595         if (ctx->msg->data_type != OID_msIndirectData &&
 596             test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) {
 597                 pr_warn("Unexpected Authenticode AuthAttr\n");
 598                 return -EBADMSG;
 599         }
 600
 601         /* We need to switch the 'CONT 0' to a 'SET OF' when we digest */
 602         sinfo->authattrs = value - (hdrlen - 1);
 603         sinfo->authattrs_len = vlen + (hdrlen - 1);
 604         return 0;
 605 }
 606
 607 /*
 608  * Note the issuing certificate serial number
 609  */
 610 int pkcs7_sig_note_serial(void *context, size_t hdrlen,
 611                           unsigned char tag,
 612                           const void *value, size_t vlen)
 613 {
 614         struct pkcs7_parse_context *ctx = context;
 615         ctx->raw_serial = value;
 616         ctx->raw_serial_size = vlen;
 617         return 0;
 618 }
 619
 620 /*
 621  * Note the issuer's name
 622  */
 623 int pkcs7_sig_note_issuer(void *context, size_t hdrlen,
 624                           unsigned char tag,
 625                           const void *value, size_t vlen)
 626 {
 627         struct pkcs7_parse_context *ctx = context;
 628         ctx->raw_issuer = value;
 629         ctx->raw_issuer_size = vlen;
 630         return 0;
 631 }
 632
 633 /*
 634  * Note the issuing cert's subjectKeyIdentifier
 635  */
 636 int pkcs7_sig_note_skid(void *context, size_t hdrlen,
 637                         unsigned char tag,
 638                         const void *value, size_t vlen)
 639 {
 640         struct pkcs7_parse_context *ctx = context;
 641
 642         pr_devel("SKID: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value);
 643
 644         ctx->raw_skid = value;
 645         ctx->raw_skid_size = vlen;
 646         return 0;
 647 }
 648
 649 /*
 650  * Note the signature data
 651  */
 652 int pkcs7_sig_note_signature(void *context, size_t hdrlen,
 653                              unsigned char tag,
 654                              const void *value, size_t vlen)
 655 {
 656         struct pkcs7_parse_context *ctx = context;
 657
 658         ctx->sinfo->sig->s = kmemdup(value, vlen, GFP_KERNEL);
 659         if (!ctx->sinfo->sig->s)
 660                 return -ENOMEM;
 661
 662         ctx->sinfo->sig->s_size = vlen;
 663         return 0;
 664 }
 665
 666 /*
 667  * Note a signature information block
 668  */
 669 int pkcs7_note_signed_info(void *context, size_t hdrlen,
 670                            unsigned char tag,
 671                            const void *value, size_t vlen)
 672 {
 673         struct pkcs7_parse_context *ctx = context;
 674         struct pkcs7_signed_info *sinfo = ctx->sinfo;
 675         struct asymmetric_key_id *kid;
 676
 677         if (ctx->msg->data_type == OID_msIndirectData && !sinfo->authattrs) {
 678                 pr_warn("Authenticode requires AuthAttrs\n");
 679                 return -EBADMSG;
 680         }
 681
 682         /* Generate cert issuer + serial number key ID */
 683         if (!ctx->expect_skid) {
 684                 kid = asymmetric_key_generate_id(ctx->raw_serial,
 685                                                  ctx->raw_serial_size,
 686                                                  ctx->raw_issuer,
 687                                                  ctx->raw_issuer_size);
 688         } else {
 689                 kid = asymmetric_key_generate_id(ctx->raw_skid,
 690                                                  ctx->raw_skid_size,
 691                                                  "", 0);
 692         }
 693         if (IS_ERR(kid))
 694                 return PTR_ERR(kid);
 695
 696         pr_devel("SINFO KID: %u [%*phN]\n", kid->len, kid->len, kid->data);
 697
 698         sinfo->sig->auth_ids[0] = kid;
 699         sinfo->index = ++ctx->sinfo_index;
 700         *ctx->ppsinfo = sinfo;
 701         ctx->ppsinfo = &sinfo->next;
 702         ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL);
 703         if (!ctx->sinfo)
 704                 return -ENOMEM;
 705         ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature),
 706                                   GFP_KERNEL);
 707         if (!ctx->sinfo->sig)
 708                 return -ENOMEM;
 709         return 0;
 710 }