1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Parse a Microsoft Individual Code Signing blob
3 *
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: "fmt
9 #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 blob
19 */
20 int 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 OID
35 */
36 int 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 putting
53 * OID_msIndividualSPKeyPurpose instead of OID_msPeImageDataObjId
54 * 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 OID
67 */
68 int 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 certificate
115 */
116 int 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
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.