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-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
14 files changed, 1654 insertions, 0 deletions
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 @@
+menuconfig ASYMMETRIC_KEY_TYPE
+ tristate "Asymmetric (public-key cryptographic) key type"
+ depends on KEYS
+ help
+ This option provides support for a key type that holds the data for
+ the asymmetric keys used for public key cryptographic operations such
+ as encryption, decryption, signature generation and signature
+ verification.
+
+if ASYMMETRIC_KEY_TYPE
+
+config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
+ tristate "Asymmetric public-key crypto algorithm subtype"
+ select MPILIB
+ help
+ This option provides support for asymmetric public key type handling.
+ If signature generation and/or verification are to be used,
+ appropriate hash algorithms (such as SHA-1) must be available.
+ ENOPKG will be reported if the requisite algorithm is unavailable.
+
+config PUBLIC_KEY_ALGO_RSA
+ tristate "RSA public-key algorithm"
+ depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE
+ select MPILIB_EXTRA
+ help
+ This option enables support for the RSA algorithm (PKCS#1, RFC3447).
+
+config X509_CERTIFICATE_PARSER
+ tristate "X.509 certificate parser"
+ depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE
+ select ASN1
+ select OID_REGISTRY
+ help
+ This option procides support for parsing X.509 format blobs for key
+ data and provides the ability to instantiate a crypto key from a
+ public key packet found inside the certificate.
+
+endif # 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 @@
+#
+# Makefile for asymmetric cryptographic keys
+#
+
+obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o
+
+asymmetric_keys-y := asymmetric_type.o signature.o
+
+obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o
+obj-$(CONFIG_PUBLIC_KEY_ALGO_RSA) += rsa.o
+
+#
+# X.509 Certificate handling
+#
+obj-$(CONFIG_X509_CERTIFICATE_PARSER) += x509_key_parser.o
+x509_key_parser-y := \
+ x509-asn1.o \
+ x509_rsakey-asn1.o \
+ x509_cert_parser.o \
+ x509_public_key.o
+
+$(obj)/x509_cert_parser.o: $(obj)/x509-asn1.h $(obj)/x509_rsakey-asn1.h
+$(obj)/x509-asn1.o: $(obj)/x509-asn1.c $(obj)/x509-asn1.h
+$(obj)/x509_rsakey-asn1.o: $(obj)/x509_rsakey-asn1.c $(obj)/x509_rsakey-asn1.h
+
+clean-files += x509-asn1.c x509-asn1.h
+clean-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 @@
+/* Internal definitions for asymmetric key type
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+static inline const char *asymmetric_key_id(const struct key *key)
+{
+ return key->type_data.p[1];
+}
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 @@
+/* Asymmetric public-key cryptography key type
+ *
+ * See Documentation/security/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#include <keys/asymmetric-subtype.h>
+#include <keys/asymmetric-parser.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "asymmetric_keys.h"
+
+MODULE_LICENSE("GPL");
+
+static LIST_HEAD(asymmetric_key_parsers);
+static DECLARE_RWSEM(asymmetric_key_parsers_sem);
+
+/*
+ * Match asymmetric keys on (part of) their name
+ * We have some shorthand methods for matching keys. We allow:
+ *
+ * "<desc>" - request a key by description
+ * "id:<id>" - request a key matching the ID
+ * "<subtype>:<id>" - request a key of a subtype
+ */
+static int asymmetric_key_match(const struct key *key, const void *description)
+{
+ const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
+ const char *spec = description;
+ const char *id, *kid;
+ ptrdiff_t speclen;
+ size_t idlen, kidlen;
+
+ if (!subtype || !spec || !*spec)
+ return 0;
+
+ /* See if the full key description matches as is */
+ if (key->description && strcmp(key->description, description) == 0)
+ return 1;
+
+ /* All tests from here on break the criterion description into a
+ * specifier, a colon and then an identifier.
+ */
+ id = strchr(spec, ':');
+ if (!id)
+ return 0;
+
+ speclen = id - spec;
+ id++;
+
+ /* Anything after here requires a partial match on the ID string */
+ kid = asymmetric_key_id(key);
+ if (!kid)
+ return 0;
+
+ idlen = strlen(id);
+ kidlen = strlen(kid);
+ if (idlen > kidlen)
+ return 0;
+
+ kid += kidlen - idlen;
+ if (strcasecmp(id, kid) != 0)
+ return 0;
+
+ if (speclen == 2 &&
+ memcmp(spec, "id", 2) == 0)
+ return 1;
+
+ if (speclen == subtype->name_len &&
+ memcmp(spec, subtype->name, speclen) == 0)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * Describe the asymmetric key
+ */
+static void asymmetric_key_describe(const struct key *key, struct seq_file *m)
+{
+ const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
+ const char *kid = asymmetric_key_id(key);
+ size_t n;
+
+ seq_puts(m, key->description);
+
+ if (subtype) {
+ seq_puts(m, ": ");
+ subtype->describe(key, m);
+
+ if (kid) {
+ seq_putc(m, ' ');
+ n = strlen(kid);
+ if (n <= 8)
+ seq_puts(m, kid);
+ else
+ seq_puts(m, kid + n - 8);
+ }
+
+ seq_puts(m, " [");
+ /* put something here to indicate the key's capabilities */
+ seq_putc(m, ']');
+ }
+}
+
+/*
+ * Preparse a asymmetric payload to get format the contents appropriately for the
+ * internal payload to cut down on the number of scans of the data performed.
+ *
+ * We also generate a proposed description from the contents of the key that
+ * can be used to name the key if the user doesn't want to provide one.
+ */
+static int asymmetric_key_preparse(struct key_preparsed_payload *prep)
+{
+ struct asymmetric_key_parser *parser;
+ int ret;
+
+ pr_devel("==>%s()\n", __func__);
+
+ if (prep->datalen == 0)
+ return -EINVAL;
+
+ down_read(&asymmetric_key_parsers_sem);
+
+ ret = -EBADMSG;
+ list_for_each_entry(parser, &asymmetric_key_parsers, link) {
+ pr_debug("Trying parser '%s'\n", parser->name);
+
+ ret = parser->parse(prep);
+ if (ret != -EBADMSG) {
+ pr_debug("Parser recognised the format (ret %d)\n",
+ ret);
+ break;
+ }
+ }
+
+ up_read(&asymmetric_key_parsers_sem);
+ pr_devel("<==%s() = %d\n", __func__, ret);
+ return ret;
+}
+
+/*
+ * Clean up the preparse data
+ */
+static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep)
+{
+ struct asymmetric_key_subtype *subtype = prep->type_data[0];
+
+ pr_devel("==>%s()\n", __func__);
+
+ if (subtype) {
+ subtype->destroy(prep->payload);
+ module_put(subtype->owner);
+ }
+ kfree(prep->type_data[1]);
+ kfree(prep->description);
+}
+
+/*
+ * Instantiate a asymmetric_key defined key. The key was preparsed, so we just
+ * have to transfer the data here.
+ */
+static int asymmetric_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
+{
+ int ret;
+
+ pr_devel("==>%s()\n", __func__);
+
+ ret = key_payload_reserve(key, prep->quotalen);
+ if (ret == 0) {
+ key->type_data.p[0] = prep->type_data[0];
+ key->type_data.p[1] = prep->type_data[1];
+ key->payload.data = prep->payload;
+ prep->type_data[0] = NULL;
+ prep->type_data[1] = NULL;
+ prep->payload = NULL;
+ }
+ pr_devel("<==%s() = %d\n", __func__, ret);
+ return ret;
+}
+
+/*
+ * dispose of the data dangling from the corpse of a asymmetric key
+ */
+static void asymmetric_key_destroy(struct key *key)
+{
+ struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key);
+ if (subtype) {
+ subtype->destroy(key->payload.data);
+ module_put(subtype->owner);
+ key->type_data.p[0] = NULL;
+ }
+ kfree(key->type_data.p[1]);
+ key->type_data.p[1] = NULL;
+}
+
+struct key_type key_type_asymmetric = {
+ .name = "asymmetric",
+ .preparse = asymmetric_key_preparse,
+ .free_preparse = asymmetric_key_free_preparse,
+ .instantiate = asymmetric_key_instantiate,
+ .match = asymmetric_key_match,
+ .destroy = asymmetric_key_destroy,
+ .describe = asymmetric_key_describe,
+};
+EXPORT_SYMBOL_GPL(key_type_asymmetric);
+
+/**
+ * register_asymmetric_key_parser - Register a asymmetric key blob parser
+ * @parser: The parser to register
+ */
+int register_asymmetric_key_parser(struct asymmetric_key_parser *parser)
+{
+ struct asymmetric_key_parser *cursor;
+ int ret;
+
+ down_write(&asymmetric_key_parsers_sem);
+
+ list_for_each_entry(cursor, &asymmetric_key_parsers, link) {
+ if (strcmp(cursor->name, parser->name) == 0) {
+ pr_err("Asymmetric key parser '%s' already registered\n",
+ parser->name);
+ ret = -EEXIST;
+ goto out;
+ }
+ }
+
+ list_add_tail(&parser->link, &asymmetric_key_parsers);
+
+ pr_notice("Asymmetric key parser '%s' registered\n", parser->name);
+ ret = 0;
+
+out:
+ up_write(&asymmetric_key_parsers_sem);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(register_asymmetric_key_parser);
+
+/**
+ * unregister_asymmetric_key_parser - Unregister a asymmetric key blob parser
+ * @parser: The parser to unregister
+ */
+void unregister_asymmetric_key_parser(struct asymmetric_key_parser *parser)
+{
+ down_write(&asymmetric_key_parsers_sem);
+ list_del(&parser->link);
+ up_write(&asymmetric_key_parsers_sem);
+
+ pr_notice("Asymmetric key parser '%s' unregistered\n", parser->name);
+}
+EXPORT_SYMBOL_GPL(unregister_asymmetric_key_parser);
+
+/*
+ * Module stuff
+ */
+static int __init asymmetric_key_init(void)
+{
+ return register_key_type(&key_type_asymmetric);
+}
+
+static void __exit asymmetric_key_cleanup(void)
+{
+ unregister_key_type(&key_type_asymmetric);
+}
+
+module_init(asymmetric_key_init);
+module_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 @@
+/* In-software asymmetric public-key crypto subtype
+ *
+ * See Documentation/crypto/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "PKEY: "fmt
+#include <linux/module.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <keys/asymmetric-subtype.h>
+#include "public_key.h"
+
+MODULE_LICENSE("GPL");
+
+const char *const pkey_algo[PKEY_ALGO__LAST] = {
+ [PKEY_ALGO_DSA] = "DSA",
+ [PKEY_ALGO_RSA] = "RSA",
+};
+EXPORT_SYMBOL_GPL(pkey_algo);
+
+const char *const pkey_hash_algo[PKEY_HASH__LAST] = {
+ [PKEY_HASH_MD4] = "md4",
+ [PKEY_HASH_MD5] = "md5",
+ [PKEY_HASH_SHA1] = "sha1",
+ [PKEY_HASH_RIPE_MD_160] = "rmd160",
+ [PKEY_HASH_SHA256] = "sha256",
+ [PKEY_HASH_SHA384] = "sha384",
+ [PKEY_HASH_SHA512] = "sha512",
+ [PKEY_HASH_SHA224] = "sha224",
+};
+EXPORT_SYMBOL_GPL(pkey_hash_algo);
+
+const char *const pkey_id_type[PKEY_ID_TYPE__LAST] = {
+ [PKEY_ID_PGP] = "PGP",
+ [PKEY_ID_X509] = "X509",
+};
+EXPORT_SYMBOL_GPL(pkey_id_type);
+
+/*
+ * Provide a part of a description of the key for /proc/keys.
+ */
+static void public_key_describe(const struct key *asymmetric_key,
+ struct seq_file *m)
+{
+ struct public_key *key = asymmetric_key->payload.data;
+
+ if (key)
+ seq_printf(m, "%s.%s",
+ pkey_id_type[key->id_type], key->algo->name);
+}
+
+/*
+ * Destroy a public key algorithm key.
+ */
+void public_key_destroy(void *payload)
+{
+ struct public_key *key = payload;
+ int i;
+
+ if (key) {
+ for (i = 0; i < ARRAY_SIZE(key->mpi); i++)
+ mpi_free(key->mpi[i]);
+ kfree(key);
+ }
+}
+EXPORT_SYMBOL_GPL(public_key_destroy);
+
+/*
+ * Verify a signature using a public key.
+ */
+static int public_key_verify_signature(const struct key *key,
+ const struct public_key_signature *sig)
+{
+ const struct public_key *pk = key->payload.data;
+
+ if (!pk->algo->verify_signature)
+ return -ENOTSUPP;
+
+ if (sig->nr_mpi != pk->algo->n_sig_mpi) {
+ pr_debug("Signature has %u MPI not %u\n",
+ sig->nr_mpi, pk->algo->n_sig_mpi);
+ return -EINVAL;
+ }
+
+ return pk->algo->verify_signature(pk, sig);
+}
+
+/*
+ * Public key algorithm asymmetric key subtype
+ */
+struct asymmetric_key_subtype public_key_subtype = {
+ .owner = THIS_MODULE,
+ .name = "public_key",
+ .describe = public_key_describe,
+ .destroy = public_key_destroy,
+ .verify_signature = public_key_verify_signature,
+};
+EXPORT_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 @@
+/* Public key algorithm internals
+ *
+ * See Documentation/crypto/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <crypto/public_key.h>
+
+extern struct asymmetric_key_subtype public_key_subtype;
+
+/*
+ * Public key algorithm definition.
+ */
+struct public_key_algorithm {
+ const char *name;
+ u8 n_pub_mpi; /* Number of MPIs in public key */
+ u8 n_sec_mpi; /* Number of MPIs in secret key */
+ u8 n_sig_mpi; /* Number of MPIs in a signature */
+ int (*verify_signature)(const struct public_key *key,
+ const struct public_key_signature *sig);
+};
+
+extern 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 @@
+/* RSA asymmetric public-key algorithm [RFC3447]
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "RSA: "fmt
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include "public_key.h"
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("RSA Public Key Algorithm");
+
+#define kenter(FMT, ...) \
+ pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__)
+#define kleave(FMT, ...) \
+ pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
+
+/*
+ * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2].
+ */
+static const u8 RSA_digest_info_MD5[] = {
+ 0x30, 0x20, 0x30, 0x0C, 0x06, 0x08,
+ 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, /* OID */
+ 0x05, 0x00, 0x04, 0x10
+};
+
+static const u8 RSA_digest_info_SHA1[] = {
+ 0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
+ 0x2B, 0x0E, 0x03, 0x02, 0x1A,
+ 0x05, 0x00, 0x04, 0x14
+};
+
+static const u8 RSA_digest_info_RIPE_MD_160[] = {
+ 0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
+ 0x2B, 0x24, 0x03, 0x02, 0x01,
+ 0x05, 0x00, 0x04, 0x14
+};
+
+static const u8 RSA_digest_info_SHA224[] = {
+ 0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09,
+ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04,
+ 0x05, 0x00, 0x04, 0x1C
+};
+
+static const u8 RSA_digest_info_SHA256[] = {
+ 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
+ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01,
+ 0x05, 0x00, 0x04, 0x20
+};
+
+static const u8 RSA_digest_info_SHA384[] = {
+ 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
+ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02,
+ 0x05, 0x00, 0x04, 0x30
+};
+
+static const u8 RSA_digest_info_SHA512[] = {
+ 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
+ 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03,
+ 0x05, 0x00, 0x04, 0x40
+};
+
+static const struct {
+ const u8 *data;
+ size_t size;
+} RSA_ASN1_templates[PKEY_HASH__LAST] = {
+#define _(X) { RSA_digest_info_##X, sizeof(RSA_digest_info_##X) }
+ [PKEY_HASH_MD5] = _(MD5),
+ [PKEY_HASH_SHA1] = _(SHA1),
+ [PKEY_HASH_RIPE_MD_160] = _(RIPE_MD_160),
+ [PKEY_HASH_SHA256] = _(SHA256),
+ [PKEY_HASH_SHA384] = _(SHA384),
+ [PKEY_HASH_SHA512] = _(SHA512),
+ [PKEY_HASH_SHA224] = _(SHA224),
+#undef _
+};
+
+/*
+ * RSAVP1() function [RFC3447 sec 5.2.2]
+ */
+static int RSAVP1(const struct public_key *key, MPI s, MPI *_m)
+{
+ MPI m;
+ int ret;
+
+ /* (1) Validate 0 <= s < n */
+ if (mpi_cmp_ui(s, 0) < 0) {
+ kleave(" = -EBADMSG [s < 0]");
+ return -EBADMSG;
+ }
+ if (mpi_cmp(s, key->rsa.n) >= 0) {
+ kleave(" = -EBADMSG [s >= n]");
+ return -EBADMSG;
+ }
+
+ m = mpi_alloc(0);
+ if (!m)
+ return -ENOMEM;
+
+ /* (2) m = s^e mod n */
+ ret = mpi_powm(m, s, key->rsa.e, key->rsa.n);
+ if (ret < 0) {
+ mpi_free(m);
+ return ret;
+ }
+
+ *_m = m;
+ return 0;
+}
+
+/*
+ * Integer to Octet String conversion [RFC3447 sec 4.1]
+ */
+static int RSA_I2OSP(MPI x, size_t xLen, u8 **_X)
+{
+ unsigned X_size, x_size;
+ int X_sign;
+ u8 *X;
+
+ /* Make sure the string is the right length. The number should begin
+ * with { 0x00, 0x01, ... } so we have to account for 15 leading zero
+ * bits not being reported by MPI.
+ */
+ x_size = mpi_get_nbits(x);
+ pr_devel("size(x)=%u xLen*8=%zu\n", x_size, xLen * 8);
+ if (x_size != xLen * 8 - 15)
+ return -ERANGE;
+
+ X = mpi_get_buffer(x, &X_size, &X_sign);
+ if (!X)
+ return -ENOMEM;
+ if (X_sign < 0) {
+ kfree(X);
+ return -EBADMSG;
+ }
+ if (X_size != xLen - 1) {
+ kfree(X);
+ return -EBADMSG;
+ }
+
+ *_X = X;
+ return 0;
+}
+
+/*
+ * Perform the RSA signature verification.
+ * @H: Value of hash of data and metadata
+ * @EM: The computed signature value
+ * @k: The size of EM (EM[0] is an invalid location but should hold 0x00)
+ * @hash_size: The size of H
+ * @asn1_template: The DigestInfo ASN.1 template
+ * @asn1_size: Size of asm1_template[]
+ */
+static int RSA_verify(const u8 *H, const u8 *EM, size_t k, size_t hash_size,
+ const u8 *asn1_template, size_t asn1_size)
+{
+ unsigned PS_end, T_offset, i;
+
+ kenter(",,%zu,%zu,%zu", k, hash_size, asn1_size);
+
+ if (k < 2 + 1 + asn1_size + hash_size)
+ return -EBADMSG;
+
+ /* Decode the EMSA-PKCS1-v1_5 */
+ if (EM[1] != 0x01) {
+ kleave(" = -EBADMSG [EM[1] == %02u]", EM[1]);
+ return -EBADMSG;
+ }
+
+ T_offset = k - (asn1_size + hash_size);
+ PS_end = T_offset - 1;
+ if (EM[PS_end] != 0x00) {
+ kleave(" = -EBADMSG [EM[T-1] == %02u]", EM[PS_end]);
+ return -EBADMSG;
+ }
+
+ for (i = 2; i < PS_end; i++) {
+ if (EM[i] != 0xff) {
+ kleave(" = -EBADMSG [EM[PS%x] == %02u]", i - 2, EM[i]);
+ return -EBADMSG;
+ }
+ }
+
+ if (memcmp(asn1_template, EM + T_offset, asn1_size) != 0) {
+ kleave(" = -EBADMSG [EM[T] ASN.1 mismatch]");
+ return -EBADMSG;
+ }
+
+ if (memcmp(H, EM + T_offset + asn1_size, hash_size) != 0) {
+ kleave(" = -EKEYREJECTED [EM[T] hash mismatch]");
+ return -EKEYREJECTED;
+ }
+
+ kleave(" = 0");
+ return 0;
+}
+
+/*
+ * Perform the verification step [RFC3447 sec 8.2.2].
+ */
+static int RSA_verify_signature(const struct public_key *key,
+ const struct public_key_signature *sig)
+{
+ size_t tsize;
+ int ret;
+
+ /* Variables as per RFC3447 sec 8.2.2 */
+ const u8 *H = sig->digest;
+ u8 *EM = NULL;
+ MPI m = NULL;
+ size_t k;
+
+ kenter("");
+
+ if (!RSA_ASN1_templates[sig->pkey_hash_algo].data)
+ return -ENOTSUPP;
+
+ /* (1) Check the signature size against the public key modulus size */
+ k = mpi_get_nbits(key->rsa.n);
+ tsize = mpi_get_nbits(sig->rsa.s);
+
+ /* According to RFC 4880 sec 3.2, length of MPI is computed starting
+ * from most significant bit. So the RFC 3447 sec 8.2.2 size check
+ * must be relaxed to conform with shorter signatures - so we fail here
+ * only if signature length is longer than modulus size.
+ */
+ pr_devel("step 1: k=%zu size(S)=%zu\n", k, tsize);
+ if (k < tsize) {
+ ret = -EBADMSG;
+ goto error;
+ }
+
+ /* Round up and convert to octets */
+ k = (k + 7) / 8;
+
+ /* (2b) Apply the RSAVP1 verification primitive to the public key */
+ ret = RSAVP1(key, sig->rsa.s, &m);
+ if (ret < 0)
+ goto error;
+
+ /* (2c) Convert the message representative (m) to an encoded message
+ * (EM) of length k octets.
+ *
+ * NOTE! The leading zero byte is suppressed by MPI, so we pass a
+ * pointer to the _preceding_ byte to RSA_verify()!
+ */
+ ret = RSA_I2OSP(m, k, &EM);
+ if (ret < 0)
+ goto error;
+
+ ret = RSA_verify(H, EM - 1, k, sig->digest_size,
+ RSA_ASN1_templates[sig->pkey_hash_algo].data,
+ RSA_ASN1_templates[sig->pkey_hash_algo].size);
+
+error:
+ kfree(EM);
+ mpi_free(m);
+ kleave(" = %d", ret);
+ return ret;
+}
+
+const struct public_key_algorithm RSA_public_key_algorithm = {
+ .name = "RSA",
+ .n_pub_mpi = 2,
+ .n_sec_mpi = 3,
+ .n_sig_mpi = 1,
+ .verify_signature = RSA_verify_signature,
+};
+EXPORT_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 @@
+/* Signature verification with an asymmetric key
+ *
+ * See Documentation/security/asymmetric-keys.txt
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <keys/asymmetric-subtype.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <crypto/public_key.h>
+#include "asymmetric_keys.h"
+
+/**
+ * verify_signature - Initiate the use of an asymmetric key to verify a signature
+ * @key: The asymmetric key to verify against
+ * @sig: The signature to check
+ *
+ * Returns 0 if successful or else an error.
+ */
+int verify_signature(const struct key *key,
+ const struct public_key_signature *sig)
+{
+ const struct asymmetric_key_subtype *subtype;
+ int ret;
+
+ pr_devel("==>%s()\n", __func__);
+
+ if (key->type != &key_type_asymmetric)
+ return -EINVAL;
+ subtype = asymmetric_key_subtype(key);
+ if (!subtype ||
+ !key->payload.data)
+ return -EINVAL;
+ if (!subtype->verify_signature)
+ return -ENOTSUPP;
+
+ ret = subtype->verify_signature(key, sig);
+
+ pr_devel("<==%s() = %d\n", __func__, ret);
+ return ret;
+}
+EXPORT_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 @@
+Certificate ::= SEQUENCE {
+ tbsCertificate TBSCertificate ({ x509_note_tbs_certificate }),
+ signatureAlgorithm AlgorithmIdentifier,
+ signature BIT STRING ({ x509_note_signature })
+ }
+
+TBSCertificate ::= SEQUENCE {
+ version [ 0 ] Version DEFAULT,
+ serialNumber CertificateSerialNumber,
+ signature AlgorithmIdentifier ({ x509_note_pkey_algo }),
+ issuer Name ({ x509_note_issuer }),
+ validity Validity,
+ subject Name ({ x509_note_subject }),
+ subjectPublicKeyInfo SubjectPublicKeyInfo,
+ issuerUniqueID [ 1 ] IMPLICIT UniqueIdentifier OPTIONAL,
+ subjectUniqueID [ 2 ] IMPLICIT UniqueIdentifier OPTIONAL,
+ extensions [ 3 ] Extensions OPTIONAL
+ }
+
+Version ::= INTEGER
+CertificateSerialNumber ::= INTEGER
+
+AlgorithmIdentifier ::= SEQUENCE {
+ algorithm OBJECT IDENTIFIER ({ x509_note_OID }),
+ parameters ANY OPTIONAL
+}
+
+Name ::= SEQUENCE OF RelativeDistinguishedName
+
+RelativeDistinguishedName ::= SET OF AttributeValueAssertion
+
+AttributeValueAssertion ::= SEQUENCE {
+ attributeType OBJECT IDENTIFIER ({ x509_note_OID }),
+ attributeValue ANY ({ x509_extract_name_segment })
+ }
+
+Validity ::= SEQUENCE {
+ notBefore Time ({ x509_note_not_before }),
+ notAfter Time ({ x509_note_not_after })
+ }
+
+Time ::= CHOICE {
+ utcTime UTCTime,
+ generalTime GeneralizedTime
+ }
+
+SubjectPublicKeyInfo ::= SEQUENCE {
+ algorithm AlgorithmIdentifier,
+ subjectPublicKey BIT STRING ({ x509_extract_key_data })
+ }
+
+UniqueIdentifier ::= BIT STRING
+
+Extensions ::= SEQUENCE OF Extension
+
+Extension ::= SEQUENCE {
+ extnid OBJECT IDENTIFIER ({ x509_note_OID }),
+ critical BOOLEAN DEFAULT,
+ extnValue OCTET STRING ({ x509_process_extension })
+ }
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 @@
+/* X.509 certificate parser
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "X.509: "fmt
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/oid_registry.h>
+#include "public_key.h"
+#include "x509_parser.h"
+#include "x509-asn1.h"
+#include "x509_rsakey-asn1.h"
+
+struct x509_parse_context {
+ struct x509_certificate *cert; /* Certificate being constructed */
+ unsigned long data; /* Start of data */
+ const void *cert_start; /* Start of cert content */
+ const void *key; /* Key data */
+ size_t key_size; /* Size of key data */
+ enum OID last_oid; /* Last OID encountered */
+ enum OID algo_oid; /* Algorithm OID */
+ unsigned char nr_mpi; /* Number of MPIs stored */
+ u8 o_size; /* Size of organizationName (O) */
+ u8 cn_size; /* Size of commonName (CN) */
+ u8 email_size; /* Size of emailAddress */
+ u16 o_offset; /* Offset of organizationName (O) */
+ u16 cn_offset; /* Offset of commonName (CN) */
+ u16 email_offset; /* Offset of emailAddress */
+};
+
+/*
+ * Free an X.509 certificate
+ */
+void x509_free_certificate(struct x509_certificate *cert)
+{
+ if (cert) {
+ public_key_destroy(cert->pub);
+ kfree(cert->issuer);
+ kfree(cert->subject);
+ kfree(cert->fingerprint);
+ kfree(cert->authority);
+ kfree(cert);
+ }
+}
+
+/*
+ * Parse an X.509 certificate
+ */
+struct x509_certificate *x509_cert_parse(const void *data, size_t datalen)
+{
+ struct x509_certificate *cert;
+ struct x509_parse_context *ctx;
+ long ret;
+
+ ret = -ENOMEM;
+ cert = kzalloc(sizeof(struct x509_certificate), GFP_KERNEL);
+ if (!cert)
+ goto error_no_cert;
+ cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL);
+ if (!cert->pub)
+ goto error_no_ctx;
+ ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL);
+ if (!ctx)
+ goto error_no_ctx;
+
+ ctx->cert = cert;
+ ctx->data = (unsigned long)data;
+
+ /* Attempt to decode the certificate */
+ ret = asn1_ber_decoder(&x509_decoder, ctx, data, datalen);
+ if (ret < 0)
+ goto error_decode;
+
+ /* Decode the public key */
+ ret = asn1_ber_decoder(&x509_rsakey_decoder, ctx,
+ ctx->key, ctx->key_size);
+ if (ret < 0)
+ goto error_decode;
+
+ kfree(ctx);
+ return cert;
+
+error_decode:
+ kfree(ctx);
+error_no_ctx:
+ x509_free_certificate(cert);
+error_no_cert:
+ return ERR_PTR(ret);
+}
+
+/*
+ * Note an OID when we find one for later processing when we know how
+ * to interpret it.
+ */
+int x509_note_OID(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+
+ ctx->last_oid = look_up_OID(value, vlen);
+ if (ctx->last_oid == OID__NR) {
+ char buffer[50];
+ sprint_oid(value, vlen, buffer, sizeof(buffer));
+ pr_debug("Unknown OID: [%lu] %s\n",
+ (unsigned long)value - ctx->data, buffer);
+ }
+ return 0;
+}
+
+/*
+ * Save the position of the TBS data so that we can check the signature over it
+ * later.
+ */
+int x509_note_tbs_certificate(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+
+ pr_debug("x509_note_tbs_certificate(,%zu,%02x,%ld,%zu)!\n",
+ hdrlen, tag, (unsigned long)value - ctx->data, vlen);
+
+ ctx->cert->tbs = value - hdrlen;
+ ctx->cert->tbs_size = vlen + hdrlen;
+ return 0;
+}
+
+/*
+ * Record the public key algorithm
+ */
+int x509_note_pkey_algo(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+
+ pr_debug("PubKey Algo: %u\n", ctx->last_oid);
+
+ switch (ctx->last_oid) {
+ case OID_md2WithRSAEncryption:
+ case OID_md3WithRSAEncryption:
+ default:
+ return -ENOPKG; /* Unsupported combination */
+
+ case OID_md4WithRSAEncryption:
+ ctx->cert->sig_hash_algo = PKEY_HASH_MD5;
+ ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+ break;
+
+ case OID_sha1WithRSAEncryption:
+ ctx->cert->sig_hash_algo = PKEY_HASH_SHA1;
+ ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+ break;
+
+ case OID_sha256WithRSAEncryption:
+ ctx->cert->sig_hash_algo = PKEY_HASH_SHA256;
+ ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+ break;
+
+ case OID_sha384WithRSAEncryption:
+ ctx->cert->sig_hash_algo = PKEY_HASH_SHA384;
+ ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+ break;
+
+ case OID_sha512WithRSAEncryption:
+ ctx->cert->sig_hash_algo = PKEY_HASH_SHA512;
+ ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+ break;
+
+ case OID_sha224WithRSAEncryption:
+ ctx->cert->sig_hash_algo = PKEY_HASH_SHA224;
+ ctx->cert->sig_pkey_algo = PKEY_ALGO_RSA;
+ break;
+ }
+
+ ctx->algo_oid = ctx->last_oid;
+ return 0;
+}
+
+/*
+ * Note the whereabouts and type of the signature.
+ */
+int x509_note_signature(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+
+ pr_debug("Signature type: %u size %zu\n", ctx->last_oid, vlen);
+
+ if (ctx->last_oid != ctx->algo_oid) {
+ pr_warn("Got cert with pkey (%u) and sig (%u) algorithm OIDs\n",
+ ctx->algo_oid, ctx->last_oid);
+ return -EINVAL;
+ }
+
+ ctx->cert->sig = value;
+ ctx->cert->sig_size = vlen;
+ return 0;
+}
+
+/*
+ * Note some of the name segments from which we'll fabricate a name.
+ */
+int x509_extract_name_segment(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+
+ switch (ctx->last_oid) {
+ case OID_commonName:
+ ctx->cn_size = vlen;
+ ctx->cn_offset = (unsigned long)value - ctx->data;
+ break;
+ case OID_organizationName:
+ ctx->o_size = vlen;
+ ctx->o_offset = (unsigned long)value - ctx->data;
+ break;
+ case OID_email_address:
+ ctx->email_size = vlen;
+ ctx->email_offset = (unsigned long)value - ctx->data;
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+/*
+ * Fabricate and save the issuer and subject names
+ */
+static int x509_fabricate_name(struct x509_parse_context *ctx, size_t hdrlen,
+ unsigned char tag,
+ char **_name, size_t vlen)
+{
+ const void *name, *data = (const void *)ctx->data;
+ size_t namesize;
+ char *buffer;
+
+ if (*_name)
+ return -EINVAL;
+
+ /* Empty name string if no material */
+ if (!ctx->cn_size && !ctx->o_size && !ctx->email_size) {
+ buffer = kmalloc(1, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+ buffer[0] = 0;
+ goto done;
+ }
+
+ if (ctx->cn_size && ctx->o_size) {
+ /* Consider combining O and CN, but use only the CN if it is
+ * prefixed by the O, or a significant portion thereof.
+ */
+ namesize = ctx->cn_size;
+ name = data + ctx->cn_offset;
+ if (ctx->cn_size >= ctx->o_size &&
+ memcmp(data + ctx->cn_offset, data + ctx->o_offset,
+ ctx->o_size) == 0)
+ goto single_component;
+ if (ctx->cn_size >= 7 &&
+ ctx->o_size >= 7 &&
+ memcmp(data + ctx->cn_offset, data + ctx->o_offset, 7) == 0)
+ goto single_component;
+
+ buffer = kmalloc(ctx->o_size + 2 + ctx->cn_size + 1,
+ GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ memcpy(buffer,
+ data + ctx->o_offset, ctx->o_size);
+ buffer[ctx->o_size + 0] = ':';
+ buffer[ctx->o_size + 1] = ' ';
+ memcpy(buffer + ctx->o_size + 2,
+ data + ctx->cn_offset, ctx->cn_size);
+ buffer[ctx->o_size + 2 + ctx->cn_size] = 0;
+ goto done;
+
+ } else if (ctx->cn_size) {
+ namesize = ctx->cn_size;
+ name = data + ctx->cn_offset;
+ } else if (ctx->o_size) {
+ namesize = ctx->o_size;
+ name = data + ctx->o_offset;
+ } else {
+ namesize = ctx->email_size;
+ name = data + ctx->email_offset;
+ }
+
+single_component:
+ buffer = kmalloc(namesize + 1, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+ memcpy(buffer, name, namesize);
+ buffer[namesize] = 0;
+
+done:
+ *_name = buffer;
+ ctx->cn_size = 0;
+ ctx->o_size = 0;
+ ctx->email_size = 0;
+ return 0;
+}
+
+int x509_note_issuer(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+ return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen);
+}
+
+int x509_note_subject(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+ return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->subject, vlen);
+}
+
+/*
+ * Extract the data for the public key algorithm
+ */
+int x509_extract_key_data(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+
+ if (ctx->last_oid != OID_rsaEncryption)
+ return -ENOPKG;
+
+ /* There seems to be an extraneous 0 byte on the front of the data */
+ ctx->cert->pkey_algo = PKEY_ALGO_RSA;
+ ctx->key = value + 1;
+ ctx->key_size = vlen - 1;
+ return 0;
+}
+
+/*
+ * Extract a RSA public key value
+ */
+int rsa_extract_mpi(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+ MPI mpi;
+
+ if (ctx->nr_mpi >= ARRAY_SIZE(ctx->cert->pub->mpi)) {
+ pr_err("Too many public key MPIs in certificate\n");
+ return -EBADMSG;
+ }
+
+ mpi = mpi_read_raw_data(value, vlen);
+ if (!mpi)
+ return -ENOMEM;
+
+ ctx->cert->pub->mpi[ctx->nr_mpi++] = mpi;
+ return 0;
+}
+
+/*
+ * Process certificate extensions that are used to qualify the certificate.
+ */
+int x509_process_extension(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+ const unsigned char *v = value;
+ char *f;
+ int i;
+
+ pr_debug("Extension: %u\n", ctx->last_oid);
+
+ if (ctx->last_oid == OID_subjectKeyIdentifier) {
+ /* Get hold of the key fingerprint */
+ if (vlen < 3)
+ return -EBADMSG;
+ if (v[0] != ASN1_OTS || v[1] != vlen - 2)
+ return -EBADMSG;
+ v += 2;
+ vlen -= 2;
+
+ f = kmalloc(vlen * 2 + 1, GFP_KERNEL);
+ if (!f)
+ return -ENOMEM;
+ for (i = 0; i < vlen; i++)
+ sprintf(f + i * 2, "%02x", v[i]);
+ pr_debug("fingerprint %s\n", f);
+ ctx->cert->fingerprint = f;
+ return 0;
+ }
+
+ if (ctx->last_oid == OID_authorityKeyIdentifier) {
+ /* Get hold of the CA key fingerprint */
+ if (vlen < 5)
+ return -EBADMSG;
+ if (v[0] != (ASN1_SEQ | (ASN1_CONS << 5)) ||
+ v[1] != vlen - 2 ||
+ v[2] != (ASN1_CONT << 6) ||
+ v[3] != vlen - 4)
+ return -EBADMSG;
+ v += 4;
+ vlen -= 4;
+
+ f = kmalloc(vlen * 2 + 1, GFP_KERNEL);
+ if (!f)
+ return -ENOMEM;
+ for (i = 0; i < vlen; i++)
+ sprintf(f + i * 2, "%02x", v[i]);
+ pr_debug("authority %s\n", f);
+ ctx->cert->authority = f;
+ return 0;
+ }
+
+ return 0;
+}
+
+/*
+ * Record a certificate time.
+ */
+static int x509_note_time(struct tm *tm, size_t hdrlen,
+ unsigned char tag,
+ const unsigned char *value, size_t vlen)
+{
+ const unsigned char *p = value;
+
+#define dec2bin(X) ((X) - '0')
+#define DD2bin(P) ({ unsigned x = dec2bin(P[0]) * 10 + dec2bin(P[1]); P += 2; x; })
+
+ if (tag == ASN1_UNITIM) {
+ /* UTCTime: YYMMDDHHMMSSZ */
+ if (vlen != 13)
+ goto unsupported_time;
+ tm->tm_year = DD2bin(p);
+ if (tm->tm_year >= 50)
+ tm->tm_year += 1900;
+ else
+ tm->tm_year += 2000;
+ } else if (tag == ASN1_GENTIM) {
+ /* GenTime: YYYYMMDDHHMMSSZ */
+ if (vlen != 15)
+ goto unsupported_time;
+ tm->tm_year = DD2bin(p) * 100 + DD2bin(p);
+ } else {
+ goto unsupported_time;
+ }
+
+ tm->tm_year -= 1900;
+ tm->tm_mon = DD2bin(p) - 1;
+ tm->tm_mday = DD2bin(p);
+ tm->tm_hour = DD2bin(p);
+ tm->tm_min = DD2bin(p);
+ tm->tm_sec = DD2bin(p);
+
+ if (*p != 'Z')
+ goto unsupported_time;
+
+ return 0;
+
+unsupported_time:
+ pr_debug("Got unsupported time [tag %02x]: '%*.*s'\n",
+ tag, (int)vlen, (int)vlen, value);
+ return -EBADMSG;
+}
+
+int x509_note_not_before(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+ return x509_note_time(&ctx->cert->valid_from, hdrlen, tag, value, vlen);
+}
+
+int x509_note_not_after(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
+{
+ struct x509_parse_context *ctx = context;
+ return x509_note_time(&ctx->cert->valid_to, hdrlen, tag, value, vlen);
+}
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 @@
+/* X.509 certificate parser internal definitions
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <crypto/public_key.h>
+
+struct x509_certificate {
+ struct x509_certificate *next;
+ struct public_key *pub; /* Public key details */
+ char *issuer; /* Name of certificate issuer */
+ char *subject; /* Name of certificate subject */
+ char *fingerprint; /* Key fingerprint as hex */
+ char *authority; /* Authority key fingerprint as hex */
+ struct tm valid_from;
+ struct tm valid_to;
+ enum pkey_algo pkey_algo : 8; /* Public key algorithm */
+ enum pkey_algo sig_pkey_algo : 8; /* Signature public key algorithm */
+ enum pkey_hash_algo sig_hash_algo : 8; /* Signature hash algorithm */
+ const void *tbs; /* Signed data */
+ size_t tbs_size; /* Size of signed data */
+ const void *sig; /* Signature data */
+ size_t sig_size; /* Size of sigature */
+};
+
+/*
+ * x509_cert_parser.c
+ */
+extern void x509_free_certificate(struct x509_certificate *cert);
+extern 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 @@
+/* Instantiate a public key crypto key from an X.509 Certificate
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "X.509: "fmt
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/mpi.h>
+#include <linux/asn1_decoder.h>
+#include <keys/asymmetric-subtype.h>
+#include <keys/asymmetric-parser.h>
+#include <crypto/hash.h>
+#include "asymmetric_keys.h"
+#include "public_key.h"
+#include "x509_parser.h"
+
+static const
+struct public_key_algorithm *x509_public_key_algorithms[PKEY_ALGO__LAST] = {
+ [PKEY_ALGO_DSA] = NULL,
+#if defined(CONFIG_PUBLIC_KEY_ALGO_RSA) || \
+ defined(CONFIG_PUBLIC_KEY_ALGO_RSA_MODULE)
+ [PKEY_ALGO_RSA] = &RSA_public_key_algorithm,
+#endif
+};
+
+/*
+ * Check the signature on a certificate using the provided public key
+ */
+static int x509_check_signature(const struct public_key *pub,
+ const struct x509_certificate *cert)
+{
+ struct public_key_signature *sig;
+ struct crypto_shash *tfm;
+ struct shash_desc *desc;
+ size_t digest_size, desc_size;
+ int ret;
+
+ pr_devel("==>%s()\n", __func__);
+
+ /* Allocate the hashing algorithm we're going to need and find out how
+ * big the hash operational data will be.
+ */
+ tfm = crypto_alloc_shash(pkey_hash_algo[cert->sig_hash_algo], 0, 0);
+ if (IS_ERR(tfm))
+ return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm);
+
+ desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
+ digest_size = crypto_shash_digestsize(tfm);
+
+ /* We allocate the hash operational data storage on the end of our
+ * context data.
+ */
+ ret = -ENOMEM;
+ sig = kzalloc(sizeof(*sig) + desc_size + digest_size, GFP_KERNEL);
+ if (!sig)
+ goto error_no_sig;
+
+ sig->pkey_hash_algo = cert->sig_hash_algo;
+ sig->digest = (u8 *)sig + sizeof(*sig) + desc_size;
+ sig->digest_size = digest_size;
+
+ desc = (void *)sig + sizeof(*sig);
+ desc->tfm = tfm;
+ desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ ret = crypto_shash_init(desc);
+ if (ret < 0)
+ goto error;
+
+ ret = -ENOMEM;
+ sig->rsa.s = mpi_read_raw_data(cert->sig, cert->sig_size);
+ if (!sig->rsa.s)
+ goto error;
+
+ ret = crypto_shash_finup(desc, cert->tbs, cert->tbs_size, sig->digest);
+ if (ret < 0)
+ goto error_mpi;
+
+ ret = pub->algo->verify_signature(pub, sig);
+
+ pr_debug("Cert Verification: %d\n", ret);
+
+error_mpi:
+ mpi_free(sig->rsa.s);
+error:
+ kfree(sig);
+error_no_sig:
+ crypto_free_shash(tfm);
+
+ pr_devel("<==%s() = %d\n", __func__, ret);
+ return ret;
+}
+
+/*
+ * Attempt to parse a data blob for a key as an X509 certificate.
+ */
+static int x509_key_preparse(struct key_preparsed_payload *prep)
+{
+ struct x509_certificate *cert;
+ struct tm now;
+ size_t srlen, sulen;
+ char *desc = NULL;
+ int ret;
+
+ cert = x509_cert_parse(prep->data, prep->datalen);
+ if (IS_ERR(cert))
+ return PTR_ERR(cert);
+
+ pr_devel("Cert Issuer: %s\n", cert->issuer);
+ pr_devel("Cert Subject: %s\n", cert->subject);
+ pr_devel("Cert Key Algo: %s\n", pkey_algo[cert->pkey_algo]);
+ pr_devel("Cert Valid From: %04ld-%02d-%02d %02d:%02d:%02d\n",
+ cert->valid_from.tm_year + 1900, cert->valid_from.tm_mon + 1,
+ cert->valid_from.tm_mday, cert->valid_from.tm_hour,
+ cert->valid_from.tm_min, cert->valid_from.tm_sec);
+ pr_devel("Cert Valid To: %04ld-%02d-%02d %02d:%02d:%02d\n",
+ cert->valid_to.tm_year + 1900, cert->valid_to.tm_mon + 1,
+ cert->valid_to.tm_mday, cert->valid_to.tm_hour,
+ cert->valid_to.tm_min, cert->valid_to.tm_sec);
+ pr_devel("Cert Signature: %s + %s\n",
+ pkey_algo[cert->sig_pkey_algo],
+ pkey_hash_algo[cert->sig_hash_algo]);
+
+ if (!cert->fingerprint || !cert->authority) {
+ pr_warn("Cert for '%s' must have SubjKeyId and AuthKeyId extensions\n",
+ cert->subject);
+ ret = -EKEYREJECTED;
+ goto error_free_cert;
+ }
+
+ time_to_tm(CURRENT_TIME.tv_sec, 0, &now);
+ pr_devel("Now: %04ld-%02d-%02d %02d:%02d:%02d\n",
+ now.tm_year + 1900, now.tm_mon + 1, now.tm_mday,
+ now.tm_hour, now.tm_min, now.tm_sec);
+ if (now.tm_year < cert->valid_from.tm_year ||
+ (now.tm_year == cert->valid_from.tm_year &&
+ (now.tm_mon < cert->valid_from.tm_mon ||
+ (now.tm_mon == cert->valid_from.tm_mon &&
+ (now.tm_mday < cert->valid_from.tm_mday ||
+ (now.tm_mday == cert->valid_from.tm_mday &&
+ (now.tm_hour < cert->valid_from.tm_hour ||
+ (now.tm_hour == cert->valid_from.tm_hour &&
+ (now.tm_min < cert->valid_from.tm_min ||
+ (now.tm_min == cert->valid_from.tm_min &&
+ (now.tm_sec < cert->valid_from.tm_sec
+ ))))))))))) {
+ pr_warn("Cert %s is not yet valid\n", cert->fingerprint);
+ ret = -EKEYREJECTED;
+ goto error_free_cert;
+ }
+ if (now.tm_year > cert->valid_to.tm_year ||
+ (now.tm_year == cert->valid_to.tm_year &&
+ (now.tm_mon > cert->valid_to.tm_mon ||
+ (now.tm_mon == cert->valid_to.tm_mon &&
+ (now.tm_mday > cert->valid_to.tm_mday ||
+ (now.tm_mday == cert->valid_to.tm_mday &&
+ (now.tm_hour > cert->valid_to.tm_hour ||
+ (now.tm_hour == cert->valid_to.tm_hour &&
+ (now.tm_min > cert->valid_to.tm_min ||
+ (now.tm_min == cert->valid_to.tm_min &&
+ (now.tm_sec > cert->valid_to.tm_sec
+ ))))))))))) {
+ pr_warn("Cert %s has expired\n", cert->fingerprint);
+ ret = -EKEYEXPIRED;
+ goto error_free_cert;
+ }
+
+ cert->pub->algo = x509_public_key_algorithms[cert->pkey_algo];
+ cert->pub->id_type = PKEY_ID_X509;
+
+ /* Check the signature on the key */
+ if (strcmp(cert->fingerprint, cert->authority) == 0) {
+ ret = x509_check_signature(cert->pub, cert);
+ if (ret < 0)
+ goto error_free_cert;
+ }
+
+ /* Propose a description */
+ sulen = strlen(cert->subject);
+ srlen = strlen(cert->fingerprint);
+ ret = -ENOMEM;
+ desc = kmalloc(sulen + 2 + srlen + 1, GFP_KERNEL);
+ if (!desc)
+ goto error_free_cert;
+ memcpy(desc, cert->subject, sulen);
+ desc[sulen] = ':';
+ desc[sulen + 1] = ' ';
+ memcpy(desc + sulen + 2, cert->fingerprint, srlen);
+ desc[sulen + 2 + srlen] = 0;
+
+ /* We're pinning the module by being linked against it */
+ __module_get(public_key_subtype.owner);
+ prep->type_data[0] = &public_key_subtype;
+ prep->type_data[1] = cert->fingerprint;
+ prep->payload = cert->pub;
+ prep->description = desc;
+ prep->quotalen = 100;
+
+ /* We've finished with the certificate */
+ cert->pub = NULL;
+ cert->fingerprint = NULL;
+ desc = NULL;
+ ret = 0;
+
+error_free_cert:
+ x509_free_certificate(cert);
+ return ret;
+}
+
+static struct asymmetric_key_parser x509_key_parser = {
+ .owner = THIS_MODULE,
+ .name = "x509",
+ .parse = x509_key_preparse,
+};
+
+/*
+ * Module stuff
+ */
+static int __init x509_key_init(void)
+{
+ return register_asymmetric_key_parser(&x509_key_parser);
+}
+
+static void __exit x509_key_exit(void)
+{
+ unregister_asymmetric_key_parser(&x509_key_parser);
+}
+
+module_init(x509_key_init);
+module_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 @@
+RSAPublicKey ::= SEQUENCE {
+ modulus INTEGER ({ rsa_extract_mpi }), -- n
+ publicExponent INTEGER ({ rsa_extract_mpi }) -- e
+ }
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-25 00:32:26 +0000