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1// SPDX-License-Identifier: GPL-2.0-or-later2/* Parse a Microsoft Individual Code Signing blob3 *4 * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.5 * Written by David Howells (dhowells@redhat.com)6 */7 8#define pr_fmt(fmt) "MSCODE: "fmt9#include <linux/kernel.h>10#include <linux/slab.h>11#include <linux/err.h>12#include <linux/oid_registry.h>13#include <crypto/pkcs7.h>14#include "verify_pefile.h"15#include "mscode.asn1.h"16 17/*18 * Parse a Microsoft Individual Code Signing blob19 */20int mscode_parse(void *_ctx, const void *content_data, size_t data_len,21 size_t asn1hdrlen)22{23 struct pefile_context *ctx = _ctx;24 25 content_data -= asn1hdrlen;26 data_len += asn1hdrlen;27 pr_devel("Data: %zu [%*ph]\n", data_len, (unsigned)(data_len),28 content_data);29 30 return asn1_ber_decoder(&mscode_decoder, ctx, content_data, data_len);31}32 33/*34 * Check the content type OID35 */36int mscode_note_content_type(void *context, size_t hdrlen,37 unsigned char tag,38 const void *value, size_t vlen)39{40 enum OID oid;41 42 oid = look_up_OID(value, vlen);43 if (oid == OID__NR) {44 char buffer[50];45 46 sprint_oid(value, vlen, buffer, sizeof(buffer));47 pr_err("Unknown OID: %s\n", buffer);48 return -EBADMSG;49 }50 51 /*52 * pesign utility had a bug where it was putting53 * OID_msIndividualSPKeyPurpose instead of OID_msPeImageDataObjId54 * So allow both OIDs.55 */56 if (oid != OID_msPeImageDataObjId &&57 oid != OID_msIndividualSPKeyPurpose) {58 pr_err("Unexpected content type OID %u\n", oid);59 return -EBADMSG;60 }61 62 return 0;63}64 65/*66 * Note the digest algorithm OID67 */68int mscode_note_digest_algo(void *context, size_t hdrlen,69 unsigned char tag,70 const void *value, size_t vlen)71{72 struct pefile_context *ctx = context;73 char buffer[50];74 enum OID oid;75 76 oid = look_up_OID(value, vlen);77 switch (oid) {78 case OID_sha1:79 ctx->digest_algo = "sha1";80 break;81 case OID_sha256:82 ctx->digest_algo = "sha256";83 break;84 case OID_sha384:85 ctx->digest_algo = "sha384";86 break;87 case OID_sha512:88 ctx->digest_algo = "sha512";89 break;90 case OID_sha3_256:91 ctx->digest_algo = "sha3-256";92 break;93 case OID_sha3_384:94 ctx->digest_algo = "sha3-384";95 break;96 case OID_sha3_512:97 ctx->digest_algo = "sha3-512";98 break;99 100 case OID__NR:101 sprint_oid(value, vlen, buffer, sizeof(buffer));102 pr_err("Unknown OID: %s\n", buffer);103 return -EBADMSG;104 105 default:106 pr_err("Unsupported content type: %u\n", oid);107 return -ENOPKG;108 }109 110 return 0;111}112 113/*114 * Note the digest we're guaranteeing with this certificate115 */116int mscode_note_digest(void *context, size_t hdrlen,117 unsigned char tag,118 const void *value, size_t vlen)119{120 struct pefile_context *ctx = context;121 122 ctx->digest = kmemdup(value, vlen, GFP_KERNEL);123 if (!ctx->digest)124 return -ENOMEM;125 126 ctx->digest_len = vlen;127 128 return 0;129}130