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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-14 16:39:34 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-14 16:39:34 -0400
commitd25282d1c9b9bc4cda7f9d3c0205108e99aa7a9d (patch)
treef414482d768b015a609924293b779b4ad0b8f764 /crypto
parentb6eea87fc6850d3531a64a27d2323a4498cd4e43 (diff)
parentdbadc17683e6c673a69b236c0f041b931cc55c42 (diff)
Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module signing support from Rusty Russell: "module signing is the highlight, but it's an all-over David Howells frenzy..." Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG. * 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits) X.509: Fix indefinite length element skip error handling X.509: Convert some printk calls to pr_devel asymmetric keys: fix printk format warning MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking MODSIGN: Make mrproper should remove generated files. MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs MODSIGN: Use the same digest for the autogen key sig as for the module sig MODSIGN: Sign modules during the build process MODSIGN: Provide a script for generating a key ID from an X.509 cert MODSIGN: Implement module signature checking MODSIGN: Provide module signing public keys to the kernel MODSIGN: Automatically generate module signing keys if missing MODSIGN: Provide Kconfig options MODSIGN: Provide gitignore and make clean rules for extra files MODSIGN: Add FIPS policy module: signature checking hook X.509: Add a crypto key parser for binary (DER) X.509 certificates MPILIB: Provide a function to read raw data into an MPI X.509: Add an ASN.1 decoder X.509: Add simple ASN.1 grammar compiler ...
Diffstat (limited to 'crypto')
-rw-r--r--crypto/Kconfig1
-rw-r--r--crypto/Makefile1
-rw-r--r--crypto/asymmetric_keys/.gitignore1
-rw-r--r--crypto/asymmetric_keys/Kconfig38
-rw-r--r--crypto/asymmetric_keys/Makefile27
-rw-r--r--crypto/asymmetric_keys/asymmetric_keys.h15
-rw-r--r--crypto/asymmetric_keys/asymmetric_type.c274
-rw-r--r--crypto/asymmetric_keys/public_key.c108
-rw-r--r--crypto/asymmetric_keys/public_key.h30
-rw-r--r--crypto/asymmetric_keys/rsa.c277
-rw-r--r--crypto/asymmetric_keys/signature.c49
-rw-r--r--crypto/asymmetric_keys/x509.asn160
-rw-r--r--crypto/asymmetric_keys/x509_cert_parser.c496
-rw-r--r--crypto/asymmetric_keys/x509_parser.h36
-rw-r--r--crypto/asymmetric_keys/x509_public_key.c239
-rw-r--r--crypto/asymmetric_keys/x509_rsakey.asn14
16 files changed, 1656 insertions, 0 deletions
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 50402dc0ea35..6563366bae80 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1216,5 +1216,6 @@ config CRYPTO_USER_API_SKCIPHER
1216 key cipher algorithms. 1216 key cipher algorithms.
1217 1217
1218source "drivers/crypto/Kconfig" 1218source "drivers/crypto/Kconfig"
1219source crypto/asymmetric_keys/Kconfig
1219 1220
1220endif # if CRYPTO 1221endif # if CRYPTO
diff --git a/crypto/Makefile b/crypto/Makefile
index a301ad2b258c..8cf61ffe3513 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -97,3 +97,4 @@ obj-$(CONFIG_CRYPTO_USER_API_SKCIPHER) += algif_skcipher.o
97# 97#
98obj-$(CONFIG_XOR_BLOCKS) += xor.o 98obj-$(CONFIG_XOR_BLOCKS) += xor.o
99obj-$(CONFIG_ASYNC_CORE) += async_tx/ 99obj-$(CONFIG_ASYNC_CORE) += async_tx/
100obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys/
diff --git a/crypto/asymmetric_keys/.gitignore b/crypto/asymmetric_keys/.gitignore
new file mode 100644
index 000000000000..ee328374dba8
--- /dev/null
+++ b/crypto/asymmetric_keys/.gitignore
@@ -0,0 +1 @@
*-asn1.[ch]
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig
new file mode 100644
index 000000000000..6d2c2ea12559
--- /dev/null
+++ b/crypto/asymmetric_keys/Kconfig
@@ -0,0 +1,38 @@
1menuconfig ASYMMETRIC_KEY_TYPE
2 tristate "Asymmetric (public-key cryptographic) key type"
3 depends on KEYS
4 help
5 This option provides support for a key type that holds the data for
6 the asymmetric keys used for public key cryptographic operations such
7 as encryption, decryption, signature generation and signature
8 verification.
9
10if ASYMMETRIC_KEY_TYPE
11
12config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
13 tristate "Asymmetric public-key crypto algorithm subtype"
14 select MPILIB
15 help
16 This option provides support for asymmetric public key type handling.
17 If signature generation and/or verification are to be used,
18 appropriate hash algorithms (such as SHA-1) must be available.
19 ENOPKG will be reported if the requisite algorithm is unavailable.
20
21config PUBLIC_KEY_ALGO_RSA
22 tristate "RSA public-key algorithm"
23 depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE
24 select MPILIB_EXTRA
25 help
26 This option enables support for the RSA algorithm (PKCS#1, RFC3447).
27
28config X509_CERTIFICATE_PARSER
29 tristate "X.509 certificate parser"
30 depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE
31 select ASN1
32 select OID_REGISTRY
33 help
34 This option procides support for parsing X.509 format blobs for key
35 data and provides the ability to instantiate a crypto key from a
36 public key packet found inside the certificate.
37
38endif # ASYMMETRIC_KEY_TYPE
diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile
new file mode 100644
index 000000000000..0727204aab68
--- /dev/null
+++ b/crypto/asymmetric_keys/Makefile
@@ -0,0 +1,27 @@
1#
2# Makefile for asymmetric cryptographic keys
3#
4
5obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o
6
7asymmetric_keys-y := asymmetric_type.o signature.o
8
9obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o
10obj-$(CONFIG_PUBLIC_KEY_ALGO_RSA) += rsa.o
11
12#
13# X.509 Certificate handling
14#
15obj-$(CONFIG_X509_CERTIFICATE_PARSER) += x509_key_parser.o
16x509_key_parser-y := \
17 x509-asn1.o \
18 x509_rsakey-asn1.o \
19 x509_cert_parser.o \
20 x509_public_key.o
21
22$(obj)/x509_cert_parser.o: $(obj)/x509-asn1.h $(obj)/x509_rsakey-asn1.h
23$(obj)/x509-asn1.o: $(obj)/x509-asn1.c $(obj)/x509-asn1.h
24$(obj)/x509_rsakey-asn1.o: $(obj)/x509_rsakey-asn1.c $(obj)/x509_rsakey-asn1.h
25
26clean-files += x509-asn1.c x509-asn1.h
27clean-files += x509_rsakey-asn1.c x509_rsakey-asn1.h
diff --git a/crypto/asymmetric_keys/asymmetric_keys.h b/crypto/asymmetric_keys/asymmetric_keys.h
new file mode 100644
index 000000000000..515b63430812
--- /dev/null
+++ b/crypto/asymmetric_keys/asymmetric_keys.h
@@ -0,0 +1,15 @@
1/* Internal definitions for asymmetric key type
2 *
3 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12static inline const char *asymmetric_key_id(const struct key *key)
13{
14 return key->type_data.p[1];
15}
diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c
new file mode 100644
index 000000000000..cf807654d221
--- /dev/null
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -0,0 +1,274 @@
1/* Asymmetric public-key cryptography key type
2 *
3 * See Documentation/security/asymmetric-keys.txt
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
6 * Written by David Howells (dhowells@redhat.com)
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public Licence
10 * as published by the Free Software Foundation; either version
11 * 2 of the Licence, or (at your option) any later version.
12 */
13#include <keys/asymmetric-subtype.h>
14#include <keys/asymmetric-parser.h>
15#include <linux/seq_file.h>
16#include <linux/module.h>
17#include <linux/slab.h>
18#include "asymmetric_keys.h"
19
20MODULE_LICENSE("GPL");
21
22static LIST_HEAD(asymmetric_key_parsers);
23static DECLARE_RWSEM(asymmetric_key_parsers_sem);
24
25/*
26 * Match asymmetric keys on (part of) their name
27 * We have some shorthand methods for matching keys. We allow:
28 *
29 * "<desc>" - request a key by description
30 * "id:<id>" - request a key matching the ID
31 * "<subtype>:<id>" - request a key of a subtype
32 */
33static int asymmetric_key_match(const struct key *key, const void *description)
34{
35 const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
36 const char *spec = description;
37 const char *id, *kid;
38 ptrdiff_t speclen;
39 size_t idlen, kidlen;
40
41 if (!subtype || !spec || !*spec)
42 return 0;
43
44 /* See if the full key description matches as is */
45 if (key->description && strcmp(key->description, description) == 0)
46 return 1;
47
48 /* All tests from here on break the criterion description into a
49 * specifier, a colon and then an identifier.
50 */
51 id = strchr(spec, ':');
52 if (!id)
53 return 0;
54
55 speclen = id - spec;
56 id++;
57
58 /* Anything after here requires a partial match on the ID string */
59 kid = asymmetric_key_id(key);
60 if (!kid)
61 return 0;
62
63 idlen = strlen(id);
64 kidlen = strlen(kid);
65 if (idlen > kidlen)
66 return 0;
67
68 kid += kidlen - idlen;
69 if (strcasecmp(id, kid) != 0)
70 return 0;
71
72 if (speclen == 2 &&
73 memcmp(spec, "id", 2) == 0)
74 return 1;
75
76 if (speclen == subtype->name_len &&
77 memcmp(spec, subtype->name, speclen) == 0)
78 return 1;
79
80 return 0;
81}
82
83/*
84 * Describe the asymmetric key
85 */
86static void asymmetric_key_describe(const struct key *key, struct seq_file *m)
87{
88 const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
89 const char *kid = asymmetric_key_id(key);
90 size_t n;
91
92 seq_puts(m, key->description);
93
94 if (subtype) {
95 seq_puts(m, ": ");
96 subtype->describe(key, m);
97
98 if (kid) {
99 seq_putc(m, ' ');
100 n = strlen(kid);
101 if (n <= 8)
102 seq_puts(m, kid);
103 else
104 seq_puts(m, kid + n - 8);
105 }
106
107 seq_puts(m, " [");
108 /* put something here to indicate the key's capabilities */
109 seq_putc(m, ']');
110 }
111}
112
113/*
114 * Preparse a asymmetric payload to get format the contents appropriately for the
115 * internal payload to cut down on the number of scans of the data performed.
116 *
117 * We also generate a proposed description from the contents of the key that
118 * can be used to name the key if the user doesn't want to provide one.
119 */
120static int asymmetric_key_preparse(struct key_preparsed_payload *prep)
121{
122 struct asymmetric_key_parser *parser;
123 int ret;
124
125 pr_devel("==>%s()\n", __func__);
126
127 if (prep->datalen == 0)
128 return -EINVAL;
129
130 down_read(&asymmetric_key_parsers_sem);
131
132 ret = -EBADMSG;
133 list_for_each_entry(parser, &asymmetric_key_parsers, link) {
134 pr_debug("Trying parser '%s'\n", parser->name);
135
136 ret = parser->parse(prep);
137 if (ret != -EBADMSG) {
138 pr_debug("Parser recognised the format (ret %d)\n",
139 ret);
140 break;
141 }
142 }
143
144 up_read(&asymmetric_key_parsers_sem);
145 pr_devel("<==%s() = %d\n", __func__, ret);
146 return ret;
147}
148
149/*
150 * Clean up the preparse data
151 */
152static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
153{
154 struct asymmetric_key_subtype *subtype = prep->type_data[0];
155
156 pr_devel("==>%s()\n", __func__);
157
158 if (subtype) {
159 subtype->destroy(prep->payload);
160 module_put(subtype->owner);
161 }
162 kfree(prep->type_data[1]);
163 kfree(prep->description);
164}
165
166/*
167 * Instantiate a asymmetric_key defined key. The key was preparsed, so we just
168 * have to transfer the data here.
169 */
170static int asymmetric_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
171{
172 int ret;
173
174 pr_devel("==>%s()\n", __func__);
175
176 ret = key_payload_reserve(key, prep->quotalen);
177 if (ret == 0) {
178 key->type_data.p[0] = prep->type_data[0];
179 key->type_data.p[1] = prep->type_data[1];
180 key->payload.data = prep->payload;
181 prep->type_data[0] = NULL;
182 prep->type_data[1] = NULL;
183 prep->payload = NULL;
184 }
185 pr_devel("<==%s() = %d\n", __func__, ret);
186 return ret;
187}
188
189/*
190 * dispose of the data dangling from the corpse of a asymmetric key
191 */
192static void asymmetric_key_destroy(struct key *key)
193{
194 struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
195 if (subtype) {
196 subtype->destroy(key->payload.data);
197 module_put(subtype->owner);
198 key->type_data.p[0] = NULL;
199 }
200 kfree(key->type_data.p[1]);
201 key->type_data.p[1] = NULL;
202}
203
204struct key_type key_type_asymmetric = {
205 .name = "asymmetric",
206 .preparse = asymmetric_key_preparse,
207 .free_preparse = asymmetric_key_free_preparse,
208 .instantiate = asymmetric_key_instantiate,
209 .match = asymmetric_key_match,
210 .destroy = asymmetric_key_destroy,
211 .describe = asymmetric_key_describe,
212};
213EXPORT_SYMBOL_GPL(key_type_asymmetric);
214
215/**
216 * register_asymmetric_key_parser - Register a asymmetric key blob parser
217 * @parser: The parser to register
218 */
219int register_asymmetric_key_parser(struct asymmetric_key_parser *parser)
220{
221 struct asymmetric_key_parser *cursor;
222 int ret;
223
224 down_write(&asymmetric_key_parsers_sem);
225
226 list_for_each_entry(cursor, &asymmetric_key_parsers, link) {
227 if (strcmp(cursor->name, parser->name) == 0) {
228 pr_err("Asymmetric key parser '%s' already registered\n",
229 parser->name);
230 ret = -EEXIST;
231 goto out;
232 }
233 }
234
235 list_add_tail(&parser->link, &asymmetric_key_parsers);
236
237 pr_notice("Asymmetric key parser '%s' registered\n", parser->name);
238 ret = 0;
239
240out:
241 up_write(&asymmetric_key_parsers_sem);
242 return ret;
243}
244EXPORT_SYMBOL_GPL(register_asymmetric_key_parser);
245
246/**
247 * unregister_asymmetric_key_parser - Unregister a asymmetric key blob parser
248 * @parser: The parser to unregister
249 */
250void unregister_asymmetric_key_parser(struct asymmetric_key_parser *parser)
251{
252 down_write(&asymmetric_key_parsers_sem);
253 list_del(&parser->link);
254 up_write(&asymmetric_key_parsers_sem);
255
256 pr_notice("Asymmetric key parser '%s' unregistered\n", parser->name);
257}
258EXPORT_SYMBOL_GPL(unregister_asymmetric_key_parser);
259
260/*
261 * Module stuff
262 */
263static int __init asymmetric_key_init(void)
264{
265 return register_key_type(&key_type_asymmetric);
266}
267
268static void __exit asymmetric_key_cleanup(void)
269{
270 unregister_key_type(&key_type_asymmetric);
271}
272
273module_init(asymmetric_key_init);
274module_exit(asymmetric_key_cleanup);
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
new file mode 100644
index 000000000000..cb2e29180a87
--- /dev/null
+++ b/crypto/asymmetric_keys/public_key.c
@@ -0,0 +1,108 @@
1/* In-software asymmetric public-key crypto subtype
2 *
3 * See Documentation/crypto/asymmetric-keys.txt
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
6 * Written by David Howells (dhowells@redhat.com)
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public Licence
10 * as published by the Free Software Foundation; either version
11 * 2 of the Licence, or (at your option) any later version.
12 */
13
14#define pr_fmt(fmt) "PKEY: "fmt
15#include <linux/module.h>
16#include <linux/export.h>
17#include <linux/kernel.h>
18#include <linux/slab.h>
19#include <linux/seq_file.h>
20#include <keys/asymmetric-subtype.h>
21#include "public_key.h"
22
23MODULE_LICENSE("GPL");
24
25const char *const pkey_algo[PKEY_ALGO__LAST] = {
26 [PKEY_ALGO_DSA] = "DSA",
27 [PKEY_ALGO_RSA] = "RSA",
28};
29EXPORT_SYMBOL_GPL(pkey_algo);
30
31const char *const pkey_hash_algo[PKEY_HASH__LAST] = {
32 [PKEY_HASH_MD4] = "md4",
33 [PKEY_HASH_MD5] = "md5",
34 [PKEY_HASH_SHA1] = "sha1",
35 [PKEY_HASH_RIPE_MD_160] = "rmd160",
36 [PKEY_HASH_SHA256] = "sha256",
37 [PKEY_HASH_SHA384] = "sha384",
38 [PKEY_HASH_SHA512] = "sha512",
39 [PKEY_HASH_SHA224] = "sha224",
40};
41EXPORT_SYMBOL_GPL(pkey_hash_algo);
42
43const char *const pkey_id_type[PKEY_ID_TYPE__LAST] = {
44 [PKEY_ID_PGP] = "PGP",
45 [PKEY_ID_X509] = "X509",
46};
47EXPORT_SYMBOL_GPL(pkey_id_type);
48
49/*
50 * Provide a part of a description of the key for /proc/keys.
51 */
52static void public_key_describe(const struct key *asymmetric_key,
53 struct seq_file *m)
54{
55 struct public_key *key = asymmetric_key->payload.data;
56
57 if (key)
58 seq_printf(m, "%s.%s",
59 pkey_id_type[key->id_type], key->algo->name);
60}
61
62/*
63 * Destroy a public key algorithm key.
64 */
65void public_key_destroy(void *payload)
66{
67 struct public_key *key = payload;
68 int i;
69
70 if (key) {
71 for (i = 0; i < ARRAY_SIZE(key->mpi); i++)
72 mpi_free(key->mpi[i]);
73 kfree(key);
74 }
75}
76EXPORT_SYMBOL_GPL(public_key_destroy);
77
78/*
79 * Verify a signature using a public key.
80 */
81static int public_key_verify_signature(const struct key *key,
82 const struct public_key_signature *sig)
83{
84 const struct public_key *pk = key->payload.data;
85
86 if (!pk->algo->verify_signature)
87 return -ENOTSUPP;
88
89 if (sig->nr_mpi != pk->algo->n_sig_mpi) {
90 pr_debug("Signature has %u MPI not %u\n",
91 sig->nr_mpi, pk->algo->n_sig_mpi);
92 return -EINVAL;
93 }
94
95 return pk->algo->verify_signature(pk, sig);
96}
97
98/*
99 * Public key algorithm asymmetric key subtype
100 */
101struct asymmetric_key_subtype public_key_subtype = {
102 .owner = THIS_MODULE,
103 .name = "public_key",
104 .describe = public_key_describe,
105 .destroy = public_key_destroy,
106 .verify_signature = public_key_verify_signature,
107};
108EXPORT_SYMBOL_GPL(public_key_subtype);
diff --git a/crypto/asymmetric_keys/public_key.h b/crypto/asymmetric_keys/public_key.h
new file mode 100644
index 000000000000..5e5e35626899
--- /dev/null
+++ b/crypto/asymmetric_keys/public_key.h
@@ -0,0 +1,30 @@
1/* Public key algorithm internals
2 *
3 * See Documentation/crypto/asymmetric-keys.txt
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
6 * Written by David Howells (dhowells@redhat.com)
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public Licence
10 * as published by the Free Software Foundation; either version
11 * 2 of the Licence, or (at your option) any later version.
12 */
13
14#include <crypto/public_key.h>
15
16extern struct asymmetric_key_subtype public_key_subtype;
17
18/*
19 * Public key algorithm definition.
20 */
21struct public_key_algorithm {
22 const char *name;
23 u8 n_pub_mpi; /* Number of MPIs in public key */
24 u8 n_sec_mpi; /* Number of MPIs in secret key */
25 u8 n_sig_mpi; /* Number of MPIs in a signature */
26 int (*verify_signature)(const struct public_key *key,
27 const struct public_key_signature *sig);
28};
29
30extern const struct public_key_algorithm RSA_public_key_algorithm;
diff --git a/crypto/asymmetric_keys/rsa.c b/crypto/asymmetric_keys/rsa.c
new file mode 100644
index 000000000000..4a6a0696f8a3
--- /dev/null
+++ b/crypto/asymmetric_keys/rsa.c
@@ -0,0 +1,277 @@
1/* RSA asymmetric public-key algorithm [RFC3447]
2 *
3 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12#define pr_fmt(fmt) "RSA: "fmt
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/slab.h>
16#include "public_key.h"
17
18MODULE_LICENSE("GPL");
19MODULE_DESCRIPTION("RSA Public Key Algorithm");
20
21#define kenter(FMT, ...) \
22 pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__)
23#define kleave(FMT, ...) \
24 pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
25
26/*
27 * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2].
28 */
29static const u8 RSA_digest_info_MD5[] = {
30 0x30, 0x20, 0x30, 0x0C, 0x06, 0x08,
31 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, /* OID */
32 0x05, 0x00, 0x04, 0x10
33};
34
35static const u8 RSA_digest_info_SHA1[] = {
36 0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
37 0x2B, 0x0E, 0x03, 0x02, 0x1A,
38 0x05, 0x00, 0x04, 0x14
39};
40
41static const u8 RSA_digest_info_RIPE_MD_160[] = {
42 0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
43 0x2B, 0x24, 0x03, 0x02, 0x01,
44 0x05, 0x00, 0x04, 0x14
45};
46
47static const u8 RSA_digest_info_SHA224[] = {
48 0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09,
49 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04,
50 0x05, 0x00, 0x04, 0x1C
51};
52
53static const u8 RSA_digest_info_SHA256[] = {
54 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
55 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01,
56 0x05, 0x00, 0x04, 0x20
57};
58
59static const u8 RSA_digest_info_SHA384[] = {
60 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
61 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02,
62 0x05, 0x00, 0x04, 0x30
63};
64
65static const u8 RSA_digest_info_SHA512[] = {
66 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
67 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03,
68 0x05, 0x00, 0x04, 0x40
69};
70
71static const struct {
72 const u8 *data;
73 size_t size;
74} RSA_ASN1_templates[PKEY_HASH__LAST] = {
75#define _(X) { RSA_digest_info_##X, sizeof(RSA_digest_info_##X) }
76 [PKEY_HASH_MD5] = _(MD5),
77 [PKEY_HASH_SHA1] = _(SHA1),
78 [PKEY_HASH_RIPE_MD_160] = _(RIPE_MD_160),
79 [PKEY_HASH_SHA256] = _(SHA256),
80 [PKEY_HASH_SHA384] = _(SHA384),
81 [PKEY_HASH_SHA512] = _(SHA512),
82 [PKEY_HASH_SHA224] = _(SHA224),
83#undef _
84};
85
86/*
87 * RSAVP1() function [RFC3447 sec 5.2.2]
88 */
89static int RSAVP1(const struct public_key *key, MPI s, MPI *_m)
90{
91 MPI m;
92 int ret;
93
94 /* (1) Validate 0 <= s < n */
95 if (mpi_cmp_ui(s, 0) < 0) {
96 kleave(" = -EBADMSG [s < 0]");
97 return -EBADMSG;
98 }
99 if (mpi_cmp(s, key->rsa.n) >= 0) {
100 kleave(" = -EBADMSG [s >= n]");
101 return -EBADMSG;
102 }
103
104 m = mpi_alloc(0);
105 if (!m)
106 return -ENOMEM;
107
108 /* (2) m = s^e mod n */
109 ret = mpi_powm(m, s, key->rsa.e, key->rsa.n);
110 if (ret < 0) {
111 mpi_free(m);
112 return ret;
113 }
114
115 *_m = m;
116 return 0;
117}
118
119/*
120 * Integer to Octet String conversion [RFC3447 sec 4.1]
121 */
122static int RSA_I2OSP(MPI x, size_t xLen, u8 **_X)
123{
124 unsigned X_size, x_size;
125 int X_sign;
126 u8 *X;
127
128 /* Make sure the string is the right length. The number should begin
129 * with { 0x00, 0x01, ... } so we have to account for 15 leading zero
130 * bits not being reported by MPI.
131 */
132 x_size = mpi_get_nbits(x);
133 pr_devel("size(x)=%u xLen*8=%zu\n", x_size, xLen * 8);
134 if (x_size != xLen * 8 - 15)
135 return -ERANGE;
136
137 X = mpi_get_buffer(x, &X_size, &X_sign);
138 if (!X)
139 return -ENOMEM;
140 if (X_sign < 0) {
141 kfree(X);
142 return -EBADMSG;
143 }
144 if (X_size != xLen - 1) {
145 kfree(X);
146 return -EBADMSG;
147 }
148
149 *_X = X;
150 return 0;
151}
152
153/*
154 * Perform the RSA signature verification.
155 * @H: Value of hash of data and metadata
156 * @EM: The computed signature value
157 * @k: The size of EM (EM[0] is an invalid location but should hold 0x00)
158 * @hash_size: The size of H
159 * @asn1_template: The DigestInfo ASN.1 template
160 * @asn1_size: Size of asm1_template[]
161 */
162static int RSA_verify(const u8 *H, const u8 *EM, size_t k, size_t hash_size,
163 const u8 *asn1_template, size_t asn1_size)
164{
165 unsigned PS_end, T_offset, i;
166
167 kenter(",,%zu,%zu,%zu", k, hash_size, asn1_size);
168
169 if (k < 2 + 1 + asn1_size + hash_size)
170 return -EBADMSG;
171
172 /* Decode the EMSA-PKCS1-v1_5 */
173 if (EM[1] != 0x01) {
174 kleave(" = -EBADMSG [EM[1] == %02u]", EM[1]);
175 return -EBADMSG;
176 }
177
178 T_offset = k - (asn1_size + hash_size);
179 PS_end = T_offset - 1;
180 if (EM[PS_end] != 0x00) {
181 kleave(" = -EBADMSG [EM[T-1] == %02u]", EM[PS_end]);
182 return -EBADMSG;
183 }
184
185 for (i = 2; i < PS_end; i++) {
186 if (EM[i] != 0xff) {
187 kleave(" = -EBADMSG [EM[PS%x] == %02u]", i - 2, EM[i]);
188 return -EBADMSG;
189 }
190 }
191
192 if (memcmp(asn1_template, EM + T_offset, asn1_size) != 0) {
193 kleave(" = -EBADMSG [EM[T] ASN.1 mismatch]");
194 return -EBADMSG;
195 }
196
197 if (memcmp(H, EM + T_offset + asn1_size, hash_size) != 0) {
198 kleave(" = -EKEYREJECTED [EM[T] hash mismatch]");
199 return -EKEYREJECTED;
200 }
201
202 kleave(" = 0");
203 return 0;
204}
205
206/*
207 * Perform the verification step [RFC3447 sec 8.2.2].
208 */
209static int RSA_verify_signature(const struct public_key *key,
210 const struct public_key_signature *sig)
211{
212 size_t tsize;
213 int ret;
214
215 /* Variables as per RFC3447 sec 8.2.2 */
216 const u8 *H = sig->digest;
217 u8 *EM = NULL;
218 MPI m = NULL;
219 size_t k;
220
221 kenter("");
222
223 if (!RSA_ASN1_templates[sig->pkey_hash_algo].data)
224 return -ENOTSUPP;
225
226 /* (1) Check the signature size against the public key modulus size */
227 k = mpi_get_nbits(key->rsa.n);
228 tsize = mpi_get_nbits(sig->rsa.s);
229
230 /* According to RFC 4880 sec 3.2, length of MPI is computed starting
231 * from most significant bit. So the RFC 3447 sec 8.2.2 size check
232 * must be relaxed to conform with shorter signatures - so we fail here
233 * only if signature length is longer than modulus size.
234 */
235 pr_devel("step 1: k=%zu size(S)=%zu\n", k, tsize);
236 if (k < tsize) {
237 ret = -EBADMSG;
238 goto error;
239 }
240
241 /* Round up and convert to octets */
242 k = (k + 7) / 8;
243
244 /* (2b) Apply the RSAVP1 verification primitive to the public key */
245 ret = RSAVP1(key, sig->rsa.s, &m);
246 if (ret < 0)
247 goto error;
248
249 /* (2c) Convert the message representative (m) to an encoded message
250 * (EM) of length k octets.
251 *
252 * NOTE! The leading zero byte is suppressed by MPI, so we pass a
253 * pointer to the _preceding_ byte to RSA_verify()!
254 */
255 ret = RSA_I2OSP(m, k, &EM);
256 if (ret < 0)
257 goto error;
258
259 ret = RSA_verify(H, EM - 1, k, sig->digest_size,
260 RSA_ASN1_templates[sig->pkey_hash_algo].data,
261 RSA_ASN1_templates[sig->pkey_hash_algo].size);
262
263error:
264 kfree(EM);
265 mpi_free(m);
266 kleave(" = %d", ret);
267 return ret;
268}
269
270const struct public_key_algorithm RSA_public_key_algorithm = {
271 .name = "RSA",
272 .n_pub_mpi = 2,
273 .n_sec_mpi = 3,
274 .n_sig_mpi = 1,
275 .verify_signature = RSA_verify_signature,
276};
277EXPORT_SYMBOL_GPL(RSA_public_key_algorithm);
diff --git a/crypto/asymmetric_keys/signature.c b/crypto/asymmetric_keys/signature.c
new file mode 100644
index 000000000000..50b3f880b4ff
--- /dev/null
+++ b/crypto/asymmetric_keys/signature.c
@@ -0,0 +1,49 @@
1/* Signature verification with an asymmetric key
2 *
3 * See Documentation/security/asymmetric-keys.txt
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
6 * Written by David Howells (dhowells@redhat.com)
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public Licence
10 * as published by the Free Software Foundation; either version
11 * 2 of the Licence, or (at your option) any later version.
12 */
13
14#include <keys/asymmetric-subtype.h>
15#include <linux/module.h>
16#include <linux/err.h>
17#include <crypto/public_key.h>
18#include "asymmetric_keys.h"
19
20/**
21 * verify_signature - Initiate the use of an asymmetric key to verify a signature
22 * @key: The asymmetric key to verify against
23 * @sig: The signature to check
24 *
25 * Returns 0 if successful or else an error.
26 */
27int verify_signature(const struct key *key,
28 const struct public_key_signature *sig)
29{
30 const struct asymmetric_key_subtype *subtype;
31 int ret;
32
33 pr_devel("==>%s()\n", __func__);
34
35 if (key->type != &key_type_asymmetric)
36 return -EINVAL;
37 subtype = asymmetric_key_subtype(key);
38 if (!subtype ||
39 !key->payload.data)
40 return -EINVAL;
41 if (!subtype->verify_signature)
42 return -ENOTSUPP;
43
44 ret = subtype->verify_signature(key, sig);
45
46 pr_devel("<==%s() = %d\n", __func__, ret);
47 return ret;
48}
49EXPORT_SYMBOL_GPL(verify_signature);
diff --git a/crypto/asymmetric_keys/x509.asn1 b/crypto/asymmetric_keys/x509.asn1
new file mode 100644
index 000000000000..bf32b3dff088
--- /dev/null
+++ b/crypto/asymmetric_keys/x509.asn1
@@ -0,0 +1,60 @@
1Certificate ::= SEQUENCE {
2 tbsCertificate TBSCertificate ({ x509_note_tbs_certificate }),
3 signatureAlgorithm AlgorithmIdentifier,
4 signature BIT STRING ({ x509_note_signature })
5 }
6
7TBSCertificate ::= SEQUENCE {
8 version [ 0 ] Version DEFAULT,
9 serialNumber CertificateSerialNumber,
10 signature AlgorithmIdentifier ({ x509_note_pkey_algo }),
11 issuer Name ({ x509_note_issuer }),
12 validity Validity,
13 subject Name ({ x509_note_subject }),
14 subjectPublicKeyInfo SubjectPublicKeyInfo,
15 issuerUniqueID [ 1 ] IMPLICIT UniqueIdentifier OPTIONAL,
16 subjectUniqueID [ 2 ] IMPLICIT UniqueIdentifier OPTIONAL,
17 extensions [ 3 ] Extensions OPTIONAL
18 }
19
20Version ::= INTEGER
21CertificateSerialNumber ::= INTEGER
22
23AlgorithmIdentifier ::= SEQUENCE {
24 algorithm OBJECT IDENTIFIER ({ x509_note_OID }),
25 parameters ANY OPTIONAL
26}
27
28Name ::= SEQUENCE OF RelativeDistinguishedName
29
30RelativeDistinguishedName ::= SET OF AttributeValueAssertion
31
32AttributeValueAssertion ::= SEQUENCE {
33 attributeType OBJECT IDENTIFIER ({ x509_note_OID }),
34 attributeValue ANY ({ x509_extract_name_segment })
35 }
36
37Validity ::= SEQUENCE {
38 notBefore Time ({ x509_note_not_before }),
39 notAfter Time ({ x509_note_not_after })
40 }
41
42Time ::= CHOICE {
43 utcTime UTCTime,
44 generalTime GeneralizedTime
45 }
46
47SubjectPublicKeyInfo ::= SEQUENCE {
48 algorithm AlgorithmIdentifier,
49 subjectPublicKey BIT STRING ({ x509_extract_key_data })
50 }
51
52UniqueIdentifier ::= BIT STRING
53
54Extensions ::= SEQUENCE OF Extension
55
56Extension ::= SEQUENCE {
57 extnid OBJECT IDENTIFIER ({ x509_note_OID }),
58 critical BOOLEAN DEFAULT,
59 extnValue OCTET STRING ({ x509_process_extension })
60 }
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
new file mode 100644
index 000000000000..7fabc4c01993
--- /dev/null
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -0,0 +1,496 @@
1/* X.509 certificate parser
2 *
3 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12#define pr_fmt(fmt) "X.509: "fmt
13#include <linux/kernel.h>
14#include <linux/slab.h>
15#include <linux/err.h>
16#include <linux/oid_registry.h>
17#include "public_key.h"
18#include "x509_parser.h"
19#include "x509-asn1.h"
20#include "x509_rsakey-asn1.h"
21
22struct x509_parse_context {
23 struct x509_certificate *cert; /* Certificate being constructed */
24 unsigned long data; /* Start of data */
25 const void *cert_start; /* Start of cert content */
26 const void *key; /* Key data */
27 size_t key_size; /* Size of key data */
28 enum OID last_oid; /* Last OID encountered */
29 enum OID algo_oid; /* Algorithm OID */
30 unsigned char nr_mpi; /* Number of MPIs stored */
31 u8 o_size; /* Size of organizationName (O) */
32 u8 cn_size; /* Size of commonName (CN) */
33 u8 email_size; /* Size of emailAddress */
34 u16 o_offset; /* Offset of organizationName (O) */
35 u16 cn_offset; /* Offset of commonName (CN) */
36 u16 email_offset; /* Offset of emailAddress */
37};
38
39/*
40 * Free an X.509 certificate
41 */
42void x509_free_certificate(struct x509_certificate *cert)
43{
44 if (cert) {
45 public_key_destroy(cert->pub);
46 kfree(cert->issuer);
47 kfree(cert->subject);
48 kfree(cert->fingerprint);
49 kfree(cert->authority);
50 kfree(cert);
51 }
52}
53
54/*
55 * Parse an X.509 certificate
56 */
57struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
58{
59 struct x509_certificate *cert;
60 struct x509_parse_context *ctx;
61 long ret;
62
63 ret = -ENOMEM;
64 cert = kzalloc(sizeof(struct x509_certificate), GFP_KERNEL);
65 if (!cert)
66 goto error_no_cert;
67 cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL);
68 if (!cert->pub)
69 goto error_no_ctx;
70 ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL);
71 if (!ctx)
72 goto error_no_ctx;
73
74 ctx->cert = cert;
75 ctx->data = (unsigned long)data;
76
77 /* Attempt to decode the certificate */
78 ret = asn1_ber_decoder(&x509_decoder, ctx, data, datalen);
79 if (ret < 0)
80 goto error_decode;
81
82 /* Decode the public key */
83 ret = asn1_ber_decoder(&x509_rsakey_decoder, ctx,
84 ctx->key, ctx->key_size);
85 if (ret < 0)
86 goto error_decode;
87
88 kfree(ctx);
89 return cert;
90
91error_decode:
92 kfree(ctx);
93error_no_ctx:
94 x509_free_certificate(cert);
95error_no_cert:
96 return ERR_PTR(ret);
97}
98
99/*
100 * Note an OID when we find one for later processing when we know how
101 * to interpret it.
102 */
103int x509_note_OID(void *context, size_t hdrlen,
104 unsigned char tag,
105 const void *value, size_t vlen)
106{
107 struct x509_parse_context *ctx = context;
108
109 ctx->last_oid = look_up_OID(value, vlen);
110 if (ctx->last_oid == OID__NR) {
111 char buffer[50];
112 sprint_oid(value, vlen, buffer, sizeof(buffer));
113 pr_debug("Unknown OID: [%lu] %s\n",
114 (unsigned long)value - ctx->data, buffer);
115 }
116 return 0;
117}
118
119/*
120 * Save the position of the TBS data so that we can check the signature over it
121 * later.
122 */
123int x509_note_tbs_certificate(void *context, size_t hdrlen,
124 unsigned char tag,
125 const void *value, size_t vlen)
126{
127 struct x509_parse_context *ctx = context;
128
129 pr_debug("x509_note_tbs_certificate(,%zu,%02x,%ld,%zu)!\n",
130 hdrlen, tag, (unsigned long)value - ctx->data, vlen);
131
132 ctx->cert->tbs = value - hdrlen;
133 ctx->cert->tbs_size = vlen + hdrlen;
134 return 0;
135}
136
137/*
138 * Record the public key algorithm
139 */
140int x509_note_pkey_algo(void *context, size_t hdrlen,
141 unsigned char tag,
142 const void *value, size_t vlen)
143{
144 struct x509_parse_context *ctx = context;
145
146 pr_debug("PubKey Algo: %u\n", ctx->last_oid);
147
148 switch (ctx->last_oid) {
149 case OID_md2WithRSAEncryption:
150 case OID_md3WithRSAEncryption:
151 default:
152 return -ENOPKG; /* Unsupported combination */
153
154 case OID_md4WithRSAEncryption:
155 ctx->cert->sig_hash_algo = PKEY_HASH_MD5;
156 ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
157 break;
158
159 case OID_sha1WithRSAEncryption:
160 ctx->cert->sig_hash_algo = PKEY_HASH_SHA1;
161 ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
162 break;
163
164 case OID_sha256WithRSAEncryption:
165 ctx->cert->sig_hash_algo = PKEY_HASH_SHA256;
166 ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
167 break;
168
169 case OID_sha384WithRSAEncryption:
170 ctx->cert->sig_hash_algo = PKEY_HASH_SHA384;
171 ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
172 break;
173
174 case OID_sha512WithRSAEncryption:
175 ctx->cert->sig_hash_algo = PKEY_HASH_SHA512;
176 ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
177 break;
178
179 case OID_sha224WithRSAEncryption:
180 ctx->cert->sig_hash_algo = PKEY_HASH_SHA224;
181 ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
182 break;
183 }
184
185 ctx->algo_oid = ctx->last_oid;
186 return 0;
187}
188
189/*
190 * Note the whereabouts and type of the signature.
191 */
192int x509_note_signature(void *context, size_t hdrlen,
193 unsigned char tag,
194 const void *value, size_t vlen)
195{
196 struct x509_parse_context *ctx = context;
197
198 pr_debug("Signature type: %u size %zu\n", ctx->last_oid, vlen);
199
200 if (ctx->last_oid != ctx->algo_oid) {
201 pr_warn("Got cert with pkey (%u) and sig (%u) algorithm OIDs\n",
202 ctx->algo_oid, ctx->last_oid);
203 return -EINVAL;
204 }
205
206 ctx->cert->sig = value;
207 ctx->cert->sig_size = vlen;
208 return 0;
209}
210
211/*
212 * Note some of the name segments from which we'll fabricate a name.
213 */
214int x509_extract_name_segment(void *context, size_t hdrlen,
215 unsigned char tag,
216 const void *value, size_t vlen)
217{
218 struct x509_parse_context *ctx = context;
219
220 switch (ctx->last_oid) {
221 case OID_commonName:
222 ctx->cn_size = vlen;
223 ctx->cn_offset = (unsigned long)value - ctx->data;
224 break;
225 case OID_organizationName:
226 ctx->o_size = vlen;
227 ctx->o_offset = (unsigned long)value - ctx->data;
228 break;
229 case OID_email_address:
230 ctx->email_size = vlen;
231 ctx->email_offset = (unsigned long)value - ctx->data;
232 break;
233 default:
234 break;
235 }
236
237 return 0;
238}
239
240/*
241 * Fabricate and save the issuer and subject names
242 */
243static int x509_fabricate_name(struct x509_parse_context *ctx, size_t hdrlen,
244 unsigned char tag,
245 char **_name, size_t vlen)
246{
247 const void *name, *data = (const void *)ctx->data;
248 size_t namesize;
249 char *buffer;
250
251 if (*_name)
252 return -EINVAL;
253
254 /* Empty name string if no material */
255 if (!ctx->cn_size && !ctx->o_size && !ctx->email_size) {
256 buffer = kmalloc(1, GFP_KERNEL);
257 if (!buffer)
258 return -ENOMEM;
259 buffer[0] = 0;
260 goto done;
261 }
262
263 if (ctx->cn_size && ctx->o_size) {
264 /* Consider combining O and CN, but use only the CN if it is
265 * prefixed by the O, or a significant portion thereof.
266 */
267 namesize = ctx->cn_size;
268 name = data + ctx->cn_offset;
269 if (ctx->cn_size >= ctx->o_size &&
270 memcmp(data + ctx->cn_offset, data + ctx->o_offset,
271 ctx->o_size) == 0)
272 goto single_component;
273 if (ctx->cn_size >= 7 &&
274 ctx->o_size >= 7 &&
275 memcmp(data + ctx->cn_offset, data + ctx->o_offset, 7) == 0)
276 goto single_component;
277
278 buffer = kmalloc(ctx->o_size + 2 + ctx->cn_size + 1,
279 GFP_KERNEL);
280 if (!buffer)
281 return -ENOMEM;
282
283 memcpy(buffer,
284 data + ctx->o_offset, ctx->o_size);
285 buffer[ctx->o_size + 0] = ':';
286 buffer[ctx->o_size + 1] = ' ';
287 memcpy(buffer + ctx->o_size + 2,
288 data + ctx->cn_offset, ctx->cn_size);
289 buffer[ctx->o_size + 2 + ctx->cn_size] = 0;
290 goto done;
291
292 } else if (ctx->cn_size) {
293 namesize = ctx->cn_size;
294 name = data + ctx->cn_offset;
295 } else if (ctx->o_size) {
296 namesize = ctx->o_size;
297 name = data + ctx->o_offset;
298 } else {
299 namesize = ctx->email_size;
300 name = data + ctx->email_offset;
301 }
302
303single_component:
304 buffer = kmalloc(namesize + 1, GFP_KERNEL);
305 if (!buffer)
306 return -ENOMEM;
307 memcpy(buffer, name, namesize);
308 buffer[namesize] = 0;
309
310done:
311 *_name = buffer;
312 ctx->cn_size = 0;
313 ctx->o_size = 0;
314 ctx->email_size = 0;
315 return 0;
316}
317
318int x509_note_issuer(void *context, size_t hdrlen,
319 unsigned char tag,
320 const void *value, size_t vlen)
321{
322 struct x509_parse_context *ctx = context;
323 return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen);
324}
325
326int x509_note_subject(void *context, size_t hdrlen,
327 unsigned char tag,
328 const void *value, size_t vlen)
329{
330 struct x509_parse_context *ctx = context;
331 return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->subject, vlen);
332}
333
334/*
335 * Extract the data for the public key algorithm
336 */
337int x509_extract_key_data(void *context, size_t hdrlen,
338 unsigned char tag,
339 const void *value, size_t vlen)
340{
341 struct x509_parse_context *ctx = context;
342
343 if (ctx->last_oid != OID_rsaEncryption)
344 return -ENOPKG;
345
346 /* There seems to be an extraneous 0 byte on the front of the data */
347 ctx->cert->pkey_algo = PKEY_ALGO_RSA;
348 ctx->key = value + 1;
349 ctx->key_size = vlen - 1;
350 return 0;
351}
352
353/*
354 * Extract a RSA public key value
355 */
356int rsa_extract_mpi(void *context, size_t hdrlen,
357 unsigned char tag,
358 const void *value, size_t vlen)
359{
360 struct x509_parse_context *ctx = context;
361 MPI mpi;
362
363 if (ctx->nr_mpi >= ARRAY_SIZE(ctx->cert->pub->mpi)) {
364 pr_err("Too many public key MPIs in certificate\n");
365 return -EBADMSG;
366 }
367
368 mpi = mpi_read_raw_data(value, vlen);
369 if (!mpi)
370 return -ENOMEM;
371
372 ctx->cert->pub->mpi[ctx->nr_mpi++] = mpi;
373 return 0;
374}
375
376/*
377 * Process certificate extensions that are used to qualify the certificate.
378 */
379int x509_process_extension(void *context, size_t hdrlen,
380 unsigned char tag,
381 const void *value, size_t vlen)
382{
383 struct x509_parse_context *ctx = context;
384 const unsigned char *v = value;
385 char *f;
386 int i;
387
388 pr_debug("Extension: %u\n", ctx->last_oid);
389
390 if (ctx->last_oid == OID_subjectKeyIdentifier) {
391 /* Get hold of the key fingerprint */
392 if (vlen < 3)
393 return -EBADMSG;
394 if (v[0] != ASN1_OTS || v[1] != vlen - 2)
395 return -EBADMSG;
396 v += 2;
397 vlen -= 2;
398
399 f = kmalloc(vlen * 2 + 1, GFP_KERNEL);
400 if (!f)
401 return -ENOMEM;
402 for (i = 0; i < vlen; i++)
403 sprintf(f + i * 2, "%02x", v[i]);
404 pr_debug("fingerprint %s\n", f);
405 ctx->cert->fingerprint = f;
406 return 0;
407 }
408
409 if (ctx->last_oid == OID_authorityKeyIdentifier) {
410 /* Get hold of the CA key fingerprint */
411 if (vlen < 5)
412 return -EBADMSG;
413 if (v[0] != (ASN1_SEQ | (ASN1_CONS << 5)) ||
414 v[1] != vlen - 2 ||
415 v[2] != (ASN1_CONT << 6) ||
416 v[3] != vlen - 4)
417 return -EBADMSG;
418 v += 4;
419 vlen -= 4;
420
421 f = kmalloc(vlen * 2 + 1, GFP_KERNEL);
422 if (!f)
423 return -ENOMEM;
424 for (i = 0; i < vlen; i++)
425 sprintf(f + i * 2, "%02x", v[i]);
426 pr_debug("authority %s\n", f);
427 ctx->cert->authority = f;
428 return 0;
429 }
430
431 return 0;
432}
433
434/*
435 * Record a certificate time.
436 */
437static int x509_note_time(struct tm *tm, size_t hdrlen,
438 unsigned char tag,
439 const unsigned char *value, size_t vlen)
440{
441 const unsigned char *p = value;
442
443#define dec2bin(X) ((X) - '0')
444#define DD2bin(P) ({ unsigned x = dec2bin(P[0]) * 10 + dec2bin(P[1]); P += 2; x; })
445
446 if (tag == ASN1_UNITIM) {
447 /* UTCTime: YYMMDDHHMMSSZ */
448 if (vlen != 13)
449 goto unsupported_time;
450 tm->tm_year = DD2bin(p);
451 if (tm->tm_year >= 50)
452 tm->tm_year += 1900;
453 else
454 tm->tm_year += 2000;
455 } else if (tag == ASN1_GENTIM) {
456 /* GenTime: YYYYMMDDHHMMSSZ */
457 if (vlen != 15)
458 goto unsupported_time;
459 tm->tm_year = DD2bin(p) * 100 + DD2bin(p);
460 } else {
461 goto unsupported_time;
462 }
463
464 tm->tm_year -= 1900;
465 tm->tm_mon = DD2bin(p) - 1;
466 tm->tm_mday = DD2bin(p);
467 tm->tm_hour = DD2bin(p);
468 tm->tm_min = DD2bin(p);
469 tm->tm_sec = DD2bin(p);
470
471 if (*p != 'Z')
472 goto unsupported_time;
473
474 return 0;
475
476unsupported_time:
477 pr_debug("Got unsupported time [tag %02x]: '%*.*s'\n",
478 tag, (int)vlen, (int)vlen, value);
479 return -EBADMSG;
480}
481
482int x509_note_not_before(void *context, size_t hdrlen,
483 unsigned char tag,
484 const void *value, size_t vlen)
485{
486 struct x509_parse_context *ctx = context;
487 return x509_note_time(&ctx->cert->valid_from, hdrlen, tag, value, vlen);
488}
489
490int x509_note_not_after(void *context, size_t hdrlen,
491 unsigned char tag,
492 const void *value, size_t vlen)
493{
494 struct x509_parse_context *ctx = context;
495 return x509_note_time(&ctx->cert->valid_to, hdrlen, tag, value, vlen);
496}
diff --git a/crypto/asymmetric_keys/x509_parser.h b/crypto/asymmetric_keys/x509_parser.h
new file mode 100644
index 000000000000..f86dc5fcc4ad
--- /dev/null
+++ b/crypto/asymmetric_keys/x509_parser.h
@@ -0,0 +1,36 @@
1/* X.509 certificate parser internal definitions
2 *
3 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12#include <crypto/public_key.h>
13
14struct x509_certificate {
15 struct x509_certificate *next;
16 struct public_key *pub; /* Public key details */
17 char *issuer; /* Name of certificate issuer */
18 char *subject; /* Name of certificate subject */
19 char *fingerprint; /* Key fingerprint as hex */
20 char *authority; /* Authority key fingerprint as hex */
21 struct tm valid_from;
22 struct tm valid_to;
23 enum pkey_algo pkey_algo : 8; /* Public key algorithm */
24 enum pkey_algo sig_pkey_algo : 8; /* Signature public key algorithm */
25 enum pkey_hash_algo sig_hash_algo : 8; /* Signature hash algorithm */
26 const void *tbs; /* Signed data */
27 size_t tbs_size; /* Size of signed data */
28 const void *sig; /* Signature data */
29 size_t sig_size; /* Size of sigature */
30};
31
32/*
33 * x509_cert_parser.c
34 */
35extern void x509_free_certificate(struct x509_certificate *cert);
36extern struct x509_certificate *x509_cert_parse(const void *data, size_t datalen);
diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c
new file mode 100644
index 000000000000..06007f0e880c
--- /dev/null
+++ b/crypto/asymmetric_keys/x509_public_key.c
@@ -0,0 +1,239 @@
1/* Instantiate a public key crypto key from an X.509 Certificate
2 *
3 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12#define pr_fmt(fmt) "X.509: "fmt
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/slab.h>
16#include <linux/err.h>
17#include <linux/mpi.h>
18#include <linux/asn1_decoder.h>
19#include <keys/asymmetric-subtype.h>
20#include <keys/asymmetric-parser.h>
21#include <crypto/hash.h>
22#include "asymmetric_keys.h"
23#include "public_key.h"
24#include "x509_parser.h"
25
26static const
27struct public_key_algorithm *x509_public_key_algorithms[PKEY_ALGO__LAST] = {
28 [PKEY_ALGO_DSA] = NULL,
29#if defined(CONFIG_PUBLIC_KEY_ALGO_RSA) || \
30 defined(CONFIG_PUBLIC_KEY_ALGO_RSA_MODULE)
31 [PKEY_ALGO_RSA] = &RSA_public_key_algorithm,
32#endif
33};
34
35/*
36 * Check the signature on a certificate using the provided public key
37 */
38static int x509_check_signature(const struct public_key *pub,
39 const struct x509_certificate *cert)
40{
41 struct public_key_signature *sig;
42 struct crypto_shash *tfm;
43 struct shash_desc *desc;
44 size_t digest_size, desc_size;
45 int ret;
46
47 pr_devel("==>%s()\n", __func__);
48
49 /* Allocate the hashing algorithm we're going to need and find out how
50 * big the hash operational data will be.
51 */
52 tfm = crypto_alloc_shash(pkey_hash_algo[cert->sig_hash_algo], 0, 0);
53 if (IS_ERR(tfm))
54 return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm);
55
56 desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
57 digest_size = crypto_shash_digestsize(tfm);
58
59 /* We allocate the hash operational data storage on the end of our
60 * context data.
61 */
62 ret = -ENOMEM;
63 sig = kzalloc(sizeof(*sig) + desc_size + digest_size, GFP_KERNEL);
64 if (!sig)
65 goto error_no_sig;
66
67 sig->pkey_hash_algo = cert->sig_hash_algo;
68 sig->digest = (u8 *)sig + sizeof(*sig) + desc_size;
69 sig->digest_size = digest_size;
70
71 desc = (void *)sig + sizeof(*sig);
72 desc->tfm = tfm;
73 desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
74
75 ret = crypto_shash_init(desc);
76 if (ret < 0)
77 goto error;
78
79 ret = -ENOMEM;
80 sig->rsa.s = mpi_read_raw_data(cert->sig, cert->sig_size);
81 if (!sig->rsa.s)
82 goto error;
83
84 ret = crypto_shash_finup(desc, cert->tbs, cert->tbs_size, sig->digest);
85 if (ret < 0)
86 goto error_mpi;
87
88 ret = pub->algo->verify_signature(pub, sig);
89
90 pr_debug("Cert Verification: %d\n", ret);
91
92error_mpi:
93 mpi_free(sig->rsa.s);
94error:
95 kfree(sig);
96error_no_sig:
97 crypto_free_shash(tfm);
98
99 pr_devel("<==%s() = %d\n", __func__, ret);
100 return ret;
101}
102
103/*
104 * Attempt to parse a data blob for a key as an X509 certificate.
105 */
106static int x509_key_preparse(struct key_preparsed_payload *prep)
107{
108 struct x509_certificate *cert;
109 struct tm now;
110 size_t srlen, sulen;
111 char *desc = NULL;
112 int ret;
113
114 cert = x509_cert_parse(prep->data, prep->datalen);
115 if (IS_ERR(cert))
116 return PTR_ERR(cert);
117
118 pr_devel("Cert Issuer: %s\n", cert->issuer);
119 pr_devel("Cert Subject: %s\n", cert->subject);
120 pr_devel("Cert Key Algo: %s\n", pkey_algo[cert->pkey_algo]);
121 pr_devel("Cert Valid From: %04ld-%02d-%02d %02d:%02d:%02d\n",
122 cert->valid_from.tm_year + 1900, cert->valid_from.tm_mon + 1,
123 cert->valid_from.tm_mday, cert->valid_from.tm_hour,
124 cert->valid_from.tm_min, cert->valid_from.tm_sec);
125 pr_devel("Cert Valid To: %04ld-%02d-%02d %02d:%02d:%02d\n",
126 cert->valid_to.tm_year + 1900, cert->valid_to.tm_mon + 1,
127 cert->valid_to.tm_mday, cert->valid_to.tm_hour,
128 cert->valid_to.tm_min, cert->valid_to.tm_sec);
129 pr_devel("Cert Signature: %s + %s\n",
130 pkey_algo[cert->sig_pkey_algo],
131 pkey_hash_algo[cert->sig_hash_algo]);
132
133 if (!cert->fingerprint || !cert->authority) {
134 pr_warn("Cert for '%s' must have SubjKeyId and AuthKeyId extensions\n",
135 cert->subject);
136 ret = -EKEYREJECTED;
137 goto error_free_cert;
138 }
139
140 time_to_tm(CURRENT_TIME.tv_sec, 0, &now);
141 pr_devel("Now: %04ld-%02d-%02d %02d:%02d:%02d\n",
142 now.tm_year + 1900, now.tm_mon + 1, now.tm_mday,
143 now.tm_hour, now.tm_min, now.tm_sec);
144 if (now.tm_year < cert->valid_from.tm_year ||
145 (now.tm_year == cert->valid_from.tm_year &&
146 (now.tm_mon < cert->valid_from.tm_mon ||
147 (now.tm_mon == cert->valid_from.tm_mon &&
148 (now.tm_mday < cert->valid_from.tm_mday ||
149 (now.tm_mday == cert->valid_from.tm_mday &&
150 (now.tm_hour < cert->valid_from.tm_hour ||
151 (now.tm_hour == cert->valid_from.tm_hour &&
152 (now.tm_min < cert->valid_from.tm_min ||
153 (now.tm_min == cert->valid_from.tm_min &&
154 (now.tm_sec < cert->valid_from.tm_sec
155 ))))))))))) {
156 pr_warn("Cert %s is not yet valid\n", cert->fingerprint);
157 ret = -EKEYREJECTED;
158 goto error_free_cert;
159 }
160 if (now.tm_year > cert->valid_to.tm_year ||
161 (now.tm_year == cert->valid_to.tm_year &&
162 (now.tm_mon > cert->valid_to.tm_mon ||
163 (now.tm_mon == cert->valid_to.tm_mon &&
164 (now.tm_mday > cert->valid_to.tm_mday ||
165 (now.tm_mday == cert->valid_to.tm_mday &&
166 (now.tm_hour > cert->valid_to.tm_hour ||
167 (now.tm_hour == cert->valid_to.tm_hour &&
168 (now.tm_min > cert->valid_to.tm_min ||
169 (now.tm_min == cert->valid_to.tm_min &&
170 (now.tm_sec > cert->valid_to.tm_sec
171 ))))))))))) {
172 pr_warn("Cert %s has expired\n", cert->fingerprint);
173 ret = -EKEYEXPIRED;
174 goto error_free_cert;
175 }
176
177 cert->pub->algo = x509_public_key_algorithms[cert->pkey_algo];
178 cert->pub->id_type = PKEY_ID_X509;
179
180 /* Check the signature on the key */
181 if (strcmp(cert->fingerprint, cert->authority) == 0) {
182 ret = x509_check_signature(cert->pub, cert);
183 if (ret < 0)
184 goto error_free_cert;
185 }
186
187 /* Propose a description */
188 sulen = strlen(cert->subject);
189 srlen = strlen(cert->fingerprint);
190 ret = -ENOMEM;
191 desc = kmalloc(sulen + 2 + srlen + 1, GFP_KERNEL);
192 if (!desc)
193 goto error_free_cert;
194 memcpy(desc, cert->subject, sulen);
195 desc[sulen] = ':';
196 desc[sulen + 1] = ' ';
197 memcpy(desc + sulen + 2, cert->fingerprint, srlen);
198 desc[sulen + 2 + srlen] = 0;
199
200 /* We're pinning the module by being linked against it */
201 __module_get(public_key_subtype.owner);
202 prep->type_data[0] = &public_key_subtype;
203 prep->type_data[1] = cert->fingerprint;
204 prep->payload = cert->pub;
205 prep->description = desc;
206 prep->quotalen = 100;
207
208 /* We've finished with the certificate */
209 cert->pub = NULL;
210 cert->fingerprint = NULL;
211 desc = NULL;
212 ret = 0;
213
214error_free_cert:
215 x509_free_certificate(cert);
216 return ret;
217}
218
219static struct asymmetric_key_parser x509_key_parser = {
220 .owner = THIS_MODULE,
221 .name = "x509",
222 .parse = x509_key_preparse,
223};
224
225/*
226 * Module stuff
227 */
228static int __init x509_key_init(void)
229{
230 return register_asymmetric_key_parser(&x509_key_parser);
231}
232
233static void __exit x509_key_exit(void)
234{
235 unregister_asymmetric_key_parser(&x509_key_parser);
236}
237
238module_init(x509_key_init);
239module_exit(x509_key_exit);
diff --git a/crypto/asymmetric_keys/x509_rsakey.asn1 b/crypto/asymmetric_keys/x509_rsakey.asn1
new file mode 100644
index 000000000000..4ec7cc6532c1
--- /dev/null
+++ b/crypto/asymmetric_keys/x509_rsakey.asn1
@@ -0,0 +1,4 @@
1RSAPublicKey ::= SEQUENCE {
2 modulus INTEGER ({ rsa_extract_mpi }), -- n
3 publicExponent INTEGER ({ rsa_extract_mpi }) -- e
4 }
generated by cgit v1.2.2 (git 2.25.0) at 2026-01-08 16:31:02 -0500