| Herbert Xu | cce9e06 | 2006-08-21 21:08:13 +1000 | [diff] [blame^] | 1 | /* |
| 2 | * Cryptographic API for algorithms (i.e., low-level API). |
| 3 | * |
| 4 | * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License as published by the Free |
| 8 | * Software Foundation; either version 2 of the License, or (at your option) |
| 9 | * any later version. |
| 10 | * |
| 11 | */ |
| 12 | |
| 13 | #include <linux/errno.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/kernel.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/string.h> |
| 18 | |
| 19 | #include "internal.h" |
| 20 | |
| 21 | static inline int crypto_set_driver_name(struct crypto_alg *alg) |
| 22 | { |
| 23 | static const char suffix[] = "-generic"; |
| 24 | char *driver_name = alg->cra_driver_name; |
| 25 | int len; |
| 26 | |
| 27 | if (*driver_name) |
| 28 | return 0; |
| 29 | |
| 30 | len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME); |
| 31 | if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME) |
| 32 | return -ENAMETOOLONG; |
| 33 | |
| 34 | memcpy(driver_name + len, suffix, sizeof(suffix)); |
| 35 | return 0; |
| 36 | } |
| 37 | |
| 38 | int crypto_register_alg(struct crypto_alg *alg) |
| 39 | { |
| 40 | int ret; |
| 41 | struct crypto_alg *q; |
| 42 | |
| 43 | if (alg->cra_alignmask & (alg->cra_alignmask + 1)) |
| 44 | return -EINVAL; |
| 45 | |
| 46 | if (alg->cra_alignmask & alg->cra_blocksize) |
| 47 | return -EINVAL; |
| 48 | |
| 49 | if (alg->cra_blocksize > PAGE_SIZE / 8) |
| 50 | return -EINVAL; |
| 51 | |
| 52 | if (alg->cra_priority < 0) |
| 53 | return -EINVAL; |
| 54 | |
| 55 | ret = crypto_set_driver_name(alg); |
| 56 | if (unlikely(ret)) |
| 57 | return ret; |
| 58 | |
| 59 | down_write(&crypto_alg_sem); |
| 60 | |
| 61 | list_for_each_entry(q, &crypto_alg_list, cra_list) { |
| 62 | if (q == alg) { |
| 63 | ret = -EEXIST; |
| 64 | goto out; |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | list_add(&alg->cra_list, &crypto_alg_list); |
| 69 | atomic_set(&alg->cra_refcnt, 1); |
| 70 | out: |
| 71 | up_write(&crypto_alg_sem); |
| 72 | return ret; |
| 73 | } |
| 74 | EXPORT_SYMBOL_GPL(crypto_register_alg); |
| 75 | |
| 76 | int crypto_unregister_alg(struct crypto_alg *alg) |
| 77 | { |
| 78 | int ret = -ENOENT; |
| 79 | struct crypto_alg *q; |
| 80 | |
| 81 | down_write(&crypto_alg_sem); |
| 82 | list_for_each_entry(q, &crypto_alg_list, cra_list) { |
| 83 | if (alg == q) { |
| 84 | list_del(&alg->cra_list); |
| 85 | ret = 0; |
| 86 | goto out; |
| 87 | } |
| 88 | } |
| 89 | out: |
| 90 | up_write(&crypto_alg_sem); |
| 91 | |
| 92 | if (ret) |
| 93 | return ret; |
| 94 | |
| 95 | BUG_ON(atomic_read(&alg->cra_refcnt) != 1); |
| 96 | if (alg->cra_destroy) |
| 97 | alg->cra_destroy(alg); |
| 98 | |
| 99 | return 0; |
| 100 | } |
| 101 | EXPORT_SYMBOL_GPL(crypto_unregister_alg); |
| 102 | |
| 103 | static int __init crypto_algapi_init(void) |
| 104 | { |
| 105 | crypto_init_proc(); |
| 106 | return 0; |
| 107 | } |
| 108 | |
| 109 | static void __exit crypto_algapi_exit(void) |
| 110 | { |
| 111 | crypto_exit_proc(); |
| 112 | } |
| 113 | |
| 114 | module_init(crypto_algapi_init); |
| 115 | module_exit(crypto_algapi_exit); |
| 116 | |
| 117 | MODULE_LICENSE("GPL"); |
| 118 | MODULE_DESCRIPTION("Cryptographic algorithms API"); |