From: David Howells <dhowells@redhat.com>
To: herbert@gondor.hengli.com.au, rusty@rustcorp.com.au
Cc: linux-crypto@vger.kernel.org, zohar@us.ibm.com,
dmitry.kasatkin@intel.com, linux-security-module@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH 04/16] KEYS: Implement asymmetric key type
Date: Fri, 14 Sep 2012 00:48:40 +0100 [thread overview]
Message-ID: <20120913234840.3575.95516.stgit@warthog.procyon.org.uk> (raw)
In-Reply-To: <20120913234802.3575.77103.stgit@warthog.procyon.org.uk>
Create a key type that can be used to represent an asymmetric key type for use
in appropriate cryptographic operations, such as encryption, decryption,
signature generation and signature verification.
The key type is "asymmetric" and can provide access to a variety of
cryptographic algorithms.
Possibly, this would be better as "public_key" - but that has the disadvantage
that "public key" is an overloaded term.
Signed-off-by: David Howells <dhowells@redhat.com>
---
crypto/Kconfig | 1
crypto/Makefile | 1
crypto/asymmetric_keys/Kconfig | 13 +++
crypto/asymmetric_keys/Makefile | 7 +
crypto/asymmetric_keys/asymmetric_keys.h | 15 +++
crypto/asymmetric_keys/asymmetric_type.c | 156 ++++++++++++++++++++++++++++++
include/keys/asymmetric-subtype.h | 55 +++++++++++
include/keys/asymmetric-type.h | 25 +++++
8 files changed, 273 insertions(+)
create mode 100644 crypto/asymmetric_keys/Kconfig
create mode 100644 crypto/asymmetric_keys/Makefile
create mode 100644 crypto/asymmetric_keys/asymmetric_keys.h
create mode 100644 crypto/asymmetric_keys/asymmetric_type.c
create mode 100644 include/keys/asymmetric-subtype.h
create mode 100644 include/keys/asymmetric-type.h
diff --git a/crypto/Kconfig b/crypto/Kconfig
index a323805..1ca0b24 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1043,5 +1043,6 @@ config CRYPTO_USER_API_SKCIPHER
key cipher algorithms.
source "drivers/crypto/Kconfig"
+source crypto/asymmetric_keys/Kconfig
endif # if CRYPTO
diff --git a/crypto/Makefile b/crypto/Makefile
index 30f33d6..ced472e 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -96,3 +96,4 @@ obj-$(CONFIG_CRYPTO_USER_API_SKCIPHER) += algif_skcipher.o
#
obj-$(CONFIG_XOR_BLOCKS) += xor.o
obj-$(CONFIG_ASYNC_CORE) += async_tx/
+obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys/
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig
new file mode 100644
index 0000000..cad29b3
--- /dev/null
+++ b/crypto/asymmetric_keys/Kconfig
@@ -0,0 +1,13 @@
+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
+
+
+endif # ASYMMETRIC_KEY_TYPE
diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile
new file mode 100644
index 0000000..b725bcc
--- /dev/null
+++ b/crypto/asymmetric_keys/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for asymmetric cryptographic keys
+#
+
+obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o
+
+asymmetric_keys-y := asymmetric_type.o
diff --git a/crypto/asymmetric_keys/asymmetric_keys.h b/crypto/asymmetric_keys/asymmetric_keys.h
new file mode 100644
index 0000000..515b634
--- /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 0000000..bfb0424
--- /dev/null
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -0,0 +1,156 @@
+/* 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 <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "asymmetric_keys.h"
+
+MODULE_LICENSE("GPL");
+
+/*
+ * 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, ']');
+ }
+}
+
+/*
+ * 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)
+{
+ return -EOPNOTSUPP;
+}
+
+/*
+ * 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",
+ .instantiate = asymmetric_key_instantiate,
+ .match = asymmetric_key_match,
+ .destroy = asymmetric_key_destroy,
+ .describe = asymmetric_key_describe,
+};
+EXPORT_SYMBOL_GPL(key_type_asymmetric);
+
+/*
+ * 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/include/keys/asymmetric-subtype.h b/include/keys/asymmetric-subtype.h
new file mode 100644
index 0000000..4b840e8
--- /dev/null
+++ b/include/keys/asymmetric-subtype.h
@@ -0,0 +1,55 @@
+/* Asymmetric public-key cryptography key subtype
+ *
+ * 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.
+ */
+
+#ifndef _KEYS_ASYMMETRIC_SUBTYPE_H
+#define _KEYS_ASYMMETRIC_SUBTYPE_H
+
+#include <linux/seq_file.h>
+#include <keys/asymmetric-type.h>
+
+struct public_key_signature;
+
+/*
+ * Keys of this type declare a subtype that indicates the handlers and
+ * capabilities.
+ */
+struct asymmetric_key_subtype {
+ struct module *owner;
+ const char *name;
+ unsigned short name_len; /* length of name */
+
+ /* Describe a key of this subtype for /proc/keys */
+ void (*describe)(const struct key *key, struct seq_file *m);
+
+ /* Destroy a key of this subtype */
+ void (*destroy)(void *payload);
+
+ /* Verify the signature on a key of this subtype (optional) */
+ int (*verify_signature)(const struct key *key,
+ const struct public_key_signature *sig);
+};
+
+/**
+ * asymmetric_key_subtype - Get the subtype from an asymmetric key
+ * @key: The key of interest.
+ *
+ * Retrieves and returns the subtype pointer of the asymmetric key from the
+ * type-specific data attached to the key.
+ */
+static inline
+struct asymmetric_key_subtype *asymmetric_key_subtype(const struct key *key)
+{
+ return key->type_data.p[0];
+}
+
+#endif /* _KEYS_ASYMMETRIC_SUBTYPE_H */
diff --git a/include/keys/asymmetric-type.h b/include/keys/asymmetric-type.h
new file mode 100644
index 0000000..7dd4734
--- /dev/null
+++ b/include/keys/asymmetric-type.h
@@ -0,0 +1,25 @@
+/* Asymmetric Public-key cryptography key type interface
+ *
+ * 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.
+ */
+
+#ifndef _KEYS_ASYMMETRIC_TYPE_H
+#define _KEYS_ASYMMETRIC_TYPE_H
+
+#include <linux/key-type.h>
+
+extern struct key_type key_type_asymmetric;
+
+/*
+ * The payload is at the discretion of the subtype.
+ */
+
+#endif /* _KEYS_ASYMMETRIC_TYPE_H */
next prev parent reply other threads:[~2012-09-13 23:53 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-13 23:48 [RFC][PATCH 00/16] Asymmetric / Public-key cryptography key type David Howells
2012-09-13 23:48 ` [PATCH 01/16] KEYS: Add payload preparsing opportunity prior to key instantiate or update David Howells
2012-09-13 23:48 ` [PATCH 02/16] MPILIB: Provide count_leading/trailing_zeros() based on arch functions David Howells
2012-09-13 23:48 ` [PATCH 03/16] KEYS: Document asymmetric key type David Howells
2012-09-13 23:48 ` David Howells [this message]
2012-09-13 23:48 ` [PATCH 05/16] KEYS: Asymmetric key pluggable data parsers David Howells
2012-09-13 23:48 ` [PATCH 06/16] KEYS: Asymmetric public-key algorithm crypto key subtype David Howells
2012-09-13 23:49 ` [PATCH 07/16] KEYS: Provide signature verification with an asymmetric key David Howells
2012-09-13 23:49 ` [PATCH 08/16] MPILIB: Reinstate mpi_cmp[_ui]() and export for RSA signature verification David Howells
2012-09-13 23:49 ` [PATCH 09/16] RSA: Implement signature verification algorithm [PKCS#1 / RFC3447] David Howells
2012-09-13 23:49 ` [PATCH 10/16] RSA: Fix signature verification for shorter signatures David Howells
2012-09-13 23:49 ` [PATCH 11/16] X.509: Implement simple static OID registry David Howells
2012-09-13 23:49 ` [PATCH 12/16] X.509: Add utility functions to render OIDs as strings David Howells
2012-09-13 23:49 ` [PATCH 13/16] X.509: Add simple ASN.1 grammar compiler David Howells
2012-09-13 23:50 ` [PATCH 14/16] X.509: Add an ASN.1 decoder David Howells
2012-09-14 9:39 ` Alan Cox
2012-09-18 17:34 ` David Howells
2012-09-18 18:51 ` Alan Cox
2012-09-18 22:19 ` Peter Jones
2012-09-19 4:17 ` James Morris
2012-09-20 9:45 ` David Howells
2012-09-18 22:03 ` David Howells
2012-09-18 22:26 ` David Howells
2012-09-19 13:05 ` David Howells
2012-09-13 23:50 ` [PATCH 15/16] MPILIB: Provide a function to read raw data into an MPI David Howells
2012-09-13 23:50 ` [PATCH 16/16] X.509: Add a crypto key parser for binary (DER) X.509 certificates David Howells
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20120913234840.3575.95516.stgit@warthog.procyon.org.uk \
--to=dhowells@redhat.com \
--cc=dmitry.kasatkin@intel.com \
--cc=herbert@gondor.hengli.com.au \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=rusty@rustcorp.com.au \
--cc=zohar@us.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).