From: David Howells Subject: [PATCH 09/21] KEYS: Asymmetric public-key algorithm crypto key subtype [ver #3] Date: Fri, 02 Dec 2011 18:44:19 +0000 Message-ID: <20111202184419.21874.83249.stgit@warthog.procyon.org.uk> References: <20111202184229.21874.25782.stgit@warthog.procyon.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-crypto@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dmitry.kasatkin@intel.com, zohar@linux.vnet.ibm.com, arjan.van.de.ven@intel.com, alan.cox@intel.com, David Howells To: keyrings@linux-nfs.org Return-path: In-Reply-To: <20111202184229.21874.25782.stgit@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org Add a subtype for supporting asymmetric public-key encryption algorithms such as DSA (FIPS-186) and RSA (PKCS#1 / RFC1337). Signed-off-by: David Howells --- security/keys/Kconfig | 9 ++++ security/keys/Makefile | 1 security/keys/public_key.c | 55 ++++++++++++++++++++++ security/keys/public_key.h | 109 ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 174 insertions(+), 0 deletions(-) create mode 100644 security/keys/public_key.c create mode 100644 security/keys/public_key.h diff --git a/security/keys/Kconfig b/security/keys/Kconfig index 290c9d3..07c7f3b 100644 --- a/security/keys/Kconfig +++ b/security/keys/Kconfig @@ -77,3 +77,12 @@ config CRYPTO_KEY_TYPE This option provides support for a type of key that holds the keys required for cryptographic operations such as encryption, decryption, signature generation and signature verification. + +config CRYPTO_KEY_PUBLIC_KEY_SUBTYPE + tristate "Asymmetric public-key crypto algorithm subtype" + depends on CRYPTO_KEY_TYPE + 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. diff --git a/security/keys/Makefile b/security/keys/Makefile index 8462904..dc3281f 100644 --- a/security/keys/Makefile +++ b/security/keys/Makefile @@ -25,5 +25,6 @@ obj-$(CONFIG_SYSCTL) += sysctl.o obj-$(CONFIG_TRUSTED_KEYS) += trusted.o obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys/ obj-$(CONFIG_CRYPTO_KEY_TYPE) += crypto_keys.o +obj-$(CONFIG_CRYPTO_KEY_PUBLIC_KEY_SUBTYPE) += public_key.o crypto_keys-y := crypto_type.o crypto_verify.o diff --git a/security/keys/public_key.c b/security/keys/public_key.c new file mode 100644 index 0000000..c00ddac --- /dev/null +++ b/security/keys/public_key.c @@ -0,0 +1,55 @@ +/* Asymmetric public key crypto subtype + * + * Copyright (C) 2011 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 +#include +#include "public_key.h" + +MODULE_LICENSE("GPL"); + +/* + * Provide a part of a description of the key for /proc/keys. + */ +static void public_key_describe(const struct key *crypto_key, + struct seq_file *m) +{ + struct public_key *key = crypto_key->payload.data; + + if (key) + seq_puts(m, key->algo->name); +} + +/* + * Destroy a public key algorithm key + */ +static 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); + } +} + +/* + * Public key algorithm crypto key subtype + */ +struct crypto_key_subtype public_key_crypto_key_subtype = { + .owner = THIS_MODULE, + .name = "public_key", + .describe = public_key_describe, + .destroy = public_key_destroy, +}; +EXPORT_SYMBOL_GPL(public_key_crypto_key_subtype); diff --git a/security/keys/public_key.h b/security/keys/public_key.h new file mode 100644 index 0000000..b5aab3d --- /dev/null +++ b/security/keys/public_key.h @@ -0,0 +1,109 @@ +/* Asymmetric public-key algorithm definitions + * + * Copyright (C) 2011 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 _LINUX_PUBLIC_KEY_H +#define _LINUX_PUBLIC_KEY_H + +#include +#include +#include + +struct public_key; +struct public_key_signature; + +enum pkey_hash_algo { + PKEY_HASH_MD5, + PKEY_HASH_SHA1, + PKEY_HASH_RIPE_MD_160, + PKEY_HASH_SHA256, + PKEY_HASH_SHA384, + PKEY_HASH_SHA512, + PKEY_HASH_SHA224, + PKEY_HASH__LAST +}; + +/* + * Public key type 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)(const struct public_key *key, + const struct public_key_signature *sig); +}; + +extern const struct public_key_algorithm DSA_public_key_algorithm; +extern const struct public_key_algorithm RSA_public_key_algorithm; + +/* + * Asymmetric public key data + */ +struct public_key { + const struct public_key_algorithm *algo; + u8 capabilities; +#define PKEY_CAN_ENCRYPT 0x01 +#define PKEY_CAN_DECRYPT 0x02 +#define PKEY_CAN_ENCDEC (PKEY_CAN_ENCRYPT | PKEY_CAN_DECRYPT) +#define PKEY_CAN_SIGN 0x04 +#define PKEY_CAN_VERIFY 0x08 +#define PKEY_CAN_SIGVER (PKEY_CAN_SIGN | PKEY_CAN_VERIFY) + union { + MPI mpi[5]; + struct { + MPI p; /* DSA prime */ + MPI q; /* DSA group order */ + MPI g; /* DSA group generator */ + MPI y; /* DSA public-key value = g^x mod p */ + MPI x; /* DSA secret exponent (if present) */ + } dsa; + struct { + MPI n; /* RSA public modulus */ + MPI e; /* RSA public encryption exponent */ + MPI d; /* RSA secret encryption exponent (if present) */ + MPI p; /* RSA secret prime (if present) */ + MPI q; /* RSA secret prime (if present) */ + } rsa; + }; + + u8 key_id[8]; /* ID of this key pair */ + u8 key_id_size; /* Number of bytes in key_id */ +}; + +/* + * Asymmetric public key algorithm signature data + */ +struct public_key_signature { + struct crypto_key_verify_context base; + u8 *digest; + enum pkey_hash_algo pkey_hash_algo : 8; + u8 signed_hash_msw[2]; + u8 digest_size; /* Number of bytes in digest */ + union { + MPI mpi[2]; + struct { + MPI s; /* m^d mod n */ + } rsa; + struct { + MPI r; + MPI s; + } dsa; + }; + struct shash_desc hash; /* This must go last! */ +}; + +extern struct crypto_key_verify_context *pgp_pkey_verify_sig_begin( + struct key *crypto_key, const u8 *sigdata, size_t siglen); + +extern struct crypto_key_subtype public_key_crypto_key_subtype; + +#endif /* _LINUX_PUBLIC_KEY_H */