xref: /linux/crypto/algboss.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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");
261