crypto/algboss.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Create default crypto algorithm instances.
   4  *
   5  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
   6  */
   7
   8 #include <crypto/internal/aead.h>
   9 #include <linux/completion.h>
  10 #include <linux/ctype.h>
  11 #include <linux/err.h>
  12 #include <linux/init.h>
  13 #include <linux/kthread.h>
  14 #include <linux/module.h>
  15 #include <linux/notifier.h>
  16 #include <linux/rtnetlink.h>
  17 #include <linux/sched/signal.h>
  18 #include <linux/slab.h>
  19 #include <linux/string.h>
  20
  21 #include "internal.h"
  22
  23 struct cryptomgr_param {
  24         struct rtattr *tb[CRYPTO_MAX_ATTRS + 2];
  25
  26         struct {
  27                 struct rtattr attr;
  28                 struct crypto_attr_type data;
  29         } type;
  30
  31         struct {
  32                 struct rtattr attr;
  33                 struct crypto_attr_alg data;
  34         } attrs[CRYPTO_MAX_ATTRS];
  35
  36         char template[CRYPTO_MAX_ALG_NAME];
  37
  38         struct crypto_larval *larval;
  39
  40         u32 otype;
  41         u32 omask;
  42 };
  43
  44 struct crypto_test_param {
  45         char driver[CRYPTO_MAX_ALG_NAME];
  46         char alg[CRYPTO_MAX_ALG_NAME];
  47         u32 type;
  48 };
  49
  50 static int cryptomgr_probe(void *data)
  51 {
  52         struct cryptomgr_param *param = data;
  53         struct crypto_template *tmpl;
  54         int err = -ENOENT;
  55
  56         tmpl = crypto_lookup_template(param->template);
  57         if (!tmpl)
  58                 goto out;
  59
  60         do {
  61                 err = tmpl->create(tmpl, param->tb);
  62         } while (err == -EAGAIN && !signal_pending(current));
  63
  64         crypto_tmpl_put(tmpl);
  65
  66 out:
  67         param->larval->adult = ERR_PTR(err);
  68         param->larval->alg.cra_flags |= CRYPTO_ALG_DEAD;
  69         complete_all(&param->larval->completion);
  70         crypto_alg_put(&param->larval->alg);
  71         kfree(param);
  72         module_put_and_kthread_exit(0);
  73 }
  74
  75 static int cryptomgr_schedule_probe(struct crypto_larval *larval)
  76 {
  77         struct task_struct *thread;
  78         struct cryptomgr_param *param;
  79         const char *name = larval->alg.cra_name;
  80         const char *p;
  81         unsigned int len;
  82         int i;
  83
  84         if (!try_module_get(THIS_MODULE))
  85                 goto err;
  86
  87         param = kzalloc(sizeof(*param), GFP_KERNEL);
  88         if (!param)
  89                 goto err_put_module;
  90
  91         for (p = name; isalnum(*p) || *p == '-' || *p == '_'; p++)
  92                 ;
  93
  94         len = p - name;
  95         if (!len || *p != '(')
  96                 goto err_free_param;
  97
  98         memcpy(param->template, name, len);
  99
 100         i = 0;
 101         for (;;) {
 102                 name = ++p;
 103
 104                 for (; isalnum(*p) || *p == '-' || *p == '_'; p++)
 105                         ;
 106
 107                 if (*p == '(') {
 108                         int recursion = 0;
 109
 110                         for (;;) {
 111                                 if (!*++p)
 112                                         goto err_free_param;
 113                                 if (*p == '(')
 114                                         recursion++;
 115                                 else if (*p == ')' && !recursion--)
 116                                         break;
 117                         }
 118
 119                         p++;
 120                 }
 121
 122                 len = p - name;
 123                 if (!len)
 124                         goto err_free_param;
 125
 126                 param->attrs[i].attr.rta_len = sizeof(param->attrs[i]);
 127                 param->attrs[i].attr.rta_type = CRYPTOA_ALG;
 128                 memcpy(param->attrs[i].data.name, name, len);
 129
 130                 param->tb[i + 1] = &param->attrs[i].attr;
 131                 i++;
 132
 133                 if (i >= CRYPTO_MAX_ATTRS)
 134                         goto err_free_param;
 135
 136                 if (*p == ')')
 137                         break;
 138
 139                 if (*p != ',')
 140                         goto err_free_param;
 141         }
 142
 143         param->tb[i + 1] = NULL;
 144
 145         param->type.attr.rta_len = sizeof(param->type);
 146         param->type.attr.rta_type = CRYPTOA_TYPE;
 147         param->type.data.type = larval->alg.cra_flags & ~CRYPTO_ALG_TESTED;
 148         param->type.data.mask = larval->mask & ~CRYPTO_ALG_TESTED;
 149         param->tb[0] = &param->type.attr;
 150
 151         param->otype = larval->alg.cra_flags;
 152         param->omask = larval->mask;
 153
 154         crypto_alg_get(&larval->alg);
 155         param->larval = larval;
 156
 157         thread = kthread_run(cryptomgr_probe, param, "cryptomgr_probe");
 158         if (IS_ERR(thread))
 159                 goto err_put_larval;
 160
 161         return NOTIFY_STOP;
 162
 163 err_put_larval:
 164         crypto_alg_put(&larval->alg);
 165 err_free_param:
 166         kfree(param);
 167 err_put_module:
 168         module_put(THIS_MODULE);
 169 err:
 170         return NOTIFY_OK;
 171 }
 172
 173 static int cryptomgr_test(void *data)
 174 {
 175         struct crypto_test_param *param = data;
 176         u32 type = param->type;
 177         int err;
 178
 179         err = alg_test(param->driver, param->alg, type, CRYPTO_ALG_TESTED);
 180
 181         crypto_alg_tested(param->driver, err);
 182
 183         kfree(param);
 184         module_put_and_kthread_exit(0);
 185 }
 186
 187 static int cryptomgr_schedule_test(struct crypto_alg *alg)
 188 {
 189         struct task_struct *thread;
 190         struct crypto_test_param *param;
 191
 192         if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
 193                 return NOTIFY_DONE;
 194
 195         if (!try_module_get(THIS_MODULE))
 196                 goto err;
 197
 198         param = kzalloc(sizeof(*param), GFP_KERNEL);
 199         if (!param)
 200                 goto err_put_module;
 201
 202         memcpy(param->driver, alg->cra_driver_name, sizeof(param->driver));
 203         memcpy(param->alg, alg->cra_name, sizeof(param->alg));
 204         param->type = alg->cra_flags;
 205
 206         thread = kthread_run(cryptomgr_test, param, "cryptomgr_test");
 207         if (IS_ERR(thread))
 208                 goto err_free_param;
 209
 210         return NOTIFY_STOP;
 211
 212 err_free_param:
 213         kfree(param);
 214 err_put_module:
 215         module_put(THIS_MODULE);
 216 err:
 217         return NOTIFY_OK;
 218 }
 219
 220 static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
 221                             void *data)
 222 {
 223         switch (msg) {
 224         case CRYPTO_MSG_ALG_REQUEST:
 225                 return cryptomgr_schedule_probe(data);
 226         case CRYPTO_MSG_ALG_REGISTER:
 227                 return cryptomgr_schedule_test(data);
 228         case CRYPTO_MSG_ALG_LOADED:
 229                 break;
 230         }
 231
 232         return NOTIFY_DONE;
 233 }
 234
 235 static struct notifier_block cryptomgr_notifier = {
 236         .notifier_call = cryptomgr_notify,
 237 };
 238
 239 static int __init cryptomgr_init(void)
 240 {
 241         return crypto_register_notifier(&cryptomgr_notifier);
 242 }
 243
 244 static void __exit cryptomgr_exit(void)
 245 {
 246         int err = crypto_unregister_notifier(&cryptomgr_notifier);
 247         BUG_ON(err);
 248 }
 249
 250 /*
 251  * This is arch_initcall() so that the crypto self-tests are run on algorithms
 252  * registered early by subsys_initcall().  subsys_initcall() is needed for
 253  * generic implementations so that they're available for comparison tests when
 254  * other implementations are registered later by module_init().
 255  */
 256 arch_initcall(cryptomgr_init);
 257 module_exit(cryptomgr_exit);
 258
 259 MODULE_LICENSE("GPL");
 260 MODULE_DESCRIPTION("Crypto Algorithm Manager");