David Howells | a9681bf | 2012-09-21 23:24:55 +0100 | [diff] [blame^] | 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 | |
| 23 | MODULE_LICENSE("GPL"); |
| 24 | |
| 25 | const char *const pkey_algo[PKEY_ALGO__LAST] = { |
| 26 | [PKEY_ALGO_DSA] = "DSA", |
| 27 | [PKEY_ALGO_RSA] = "RSA", |
| 28 | }; |
| 29 | EXPORT_SYMBOL_GPL(pkey_algo); |
| 30 | |
| 31 | const 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 | }; |
| 41 | EXPORT_SYMBOL_GPL(pkey_hash_algo); |
| 42 | |
| 43 | const char *const pkey_id_type[PKEY_ID_TYPE__LAST] = { |
| 44 | [PKEY_ID_PGP] = "PGP", |
| 45 | [PKEY_ID_X509] = "X509", |
| 46 | }; |
| 47 | EXPORT_SYMBOL_GPL(pkey_id_type); |
| 48 | |
| 49 | /* |
| 50 | * Provide a part of a description of the key for /proc/keys. |
| 51 | */ |
| 52 | static 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 | */ |
| 65 | void 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 | } |
| 76 | EXPORT_SYMBOL_GPL(public_key_destroy); |
| 77 | |
| 78 | /* |
| 79 | * Verify a signature using a public key. |
| 80 | */ |
| 81 | static 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 | */ |
| 101 | struct 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 | }; |
| 108 | EXPORT_SYMBOL_GPL(public_key_subtype); |