xref: /linux/crypto/algboss.c (revision 652e01be364b5bf2e7d4097831d1510c7301bdc2)
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;
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->alg.cra_flags |= CRYPTO_ALG_DEAD;
68 	complete_all(&param->larval->completion);
69 	crypto_alg_put(&param->larval->alg);
70 	kfree(param);
71 	module_put_and_kthread_exit(0);
72 }
73 
74 static int cryptomgr_schedule_probe(struct crypto_larval *larval)
75 {
76 	struct task_struct *thread;
77 	struct cryptomgr_param *param;
78 	const char *name = larval->alg.cra_name;
79 	const char *p;
80 	unsigned int len;
81 	int i;
82 
83 	if (!try_module_get(THIS_MODULE))
84 		goto err;
85 
86 	param = kzalloc(sizeof(*param), GFP_KERNEL);
87 	if (!param)
88 		goto err_put_module;
89 
90 	for (p = name; isalnum(*p) || *p == '-' || *p == '_'; p++)
91 		;
92 
93 	len = p - name;
94 	if (!len || *p != '(')
95 		goto err_free_param;
96 
97 	memcpy(param->template, name, len);
98 
99 	i = 0;
100 	for (;;) {
101 		name = ++p;
102 
103 		for (; isalnum(*p) || *p == '-' || *p == '_'; p++)
104 			;
105 
106 		if (*p == '(') {
107 			int recursion = 0;
108 
109 			for (;;) {
110 				if (!*++p)
111 					goto err_free_param;
112 				if (*p == '(')
113 					recursion++;
114 				else if (*p == ')' && !recursion--)
115 					break;
116 			}
117 
118 			p++;
119 		}
120 
121 		len = p - name;
122 		if (!len)
123 			goto err_free_param;
124 
125 		param->attrs[i].attr.rta_len = sizeof(param->attrs[i]);
126 		param->attrs[i].attr.rta_type = CRYPTOA_ALG;
127 		memcpy(param->attrs[i].data.name, name, len);
128 
129 		param->tb[i + 1] = &param->attrs[i].attr;
130 		i++;
131 
132 		if (i >= CRYPTO_MAX_ATTRS)
133 			goto err_free_param;
134 
135 		if (*p == ')')
136 			break;
137 
138 		if (*p != ',')
139 			goto err_free_param;
140 	}
141 
142 	param->tb[i + 1] = NULL;
143 
144 	param->type.attr.rta_len = sizeof(param->type);
145 	param->type.attr.rta_type = CRYPTOA_TYPE;
146 	param->type.data.type = larval->alg.cra_flags & ~CRYPTO_ALG_TESTED;
147 	param->type.data.mask = larval->mask & ~CRYPTO_ALG_TESTED;
148 	param->tb[0] = &param->type.attr;
149 
150 	param->otype = larval->alg.cra_flags;
151 	param->omask = larval->mask;
152 
153 	crypto_alg_get(&larval->alg);
154 	param->larval = larval;
155 
156 	thread = kthread_run(cryptomgr_probe, param, "cryptomgr_probe");
157 	if (IS_ERR(thread))
158 		goto err_put_larval;
159 
160 	return NOTIFY_STOP;
161 
162 err_put_larval:
163 	crypto_alg_put(&larval->alg);
164 err_free_param:
165 	kfree(param);
166 err_put_module:
167 	module_put(THIS_MODULE);
168 err:
169 	return NOTIFY_OK;
170 }
171 
172 static int cryptomgr_test(void *data)
173 {
174 	struct crypto_test_param *param = data;
175 	u32 type = param->type;
176 	int err;
177 
178 	err = alg_test(param->driver, param->alg, type, CRYPTO_ALG_TESTED);
179 
180 	crypto_alg_tested(param->driver, err);
181 
182 	kfree(param);
183 	module_put_and_kthread_exit(0);
184 }
185 
186 static int cryptomgr_schedule_test(struct crypto_alg *alg)
187 {
188 	struct task_struct *thread;
189 	struct crypto_test_param *param;
190 
191 	if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
192 		return NOTIFY_DONE;
193 
194 	if (!try_module_get(THIS_MODULE))
195 		goto err;
196 
197 	param = kzalloc(sizeof(*param), GFP_KERNEL);
198 	if (!param)
199 		goto err_put_module;
200 
201 	memcpy(param->driver, alg->cra_driver_name, sizeof(param->driver));
202 	memcpy(param->alg, alg->cra_name, sizeof(param->alg));
203 	param->type = alg->cra_flags;
204 
205 	thread = kthread_run(cryptomgr_test, param, "cryptomgr_test");
206 	if (IS_ERR(thread))
207 		goto err_free_param;
208 
209 	return NOTIFY_STOP;
210 
211 err_free_param:
212 	kfree(param);
213 err_put_module:
214 	module_put(THIS_MODULE);
215 err:
216 	return NOTIFY_OK;
217 }
218 
219 static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
220 			    void *data)
221 {
222 	switch (msg) {
223 	case CRYPTO_MSG_ALG_REQUEST:
224 		return cryptomgr_schedule_probe(data);
225 	case CRYPTO_MSG_ALG_REGISTER:
226 		return cryptomgr_schedule_test(data);
227 	case CRYPTO_MSG_ALG_LOADED:
228 		break;
229 	}
230 
231 	return NOTIFY_DONE;
232 }
233 
234 static struct notifier_block cryptomgr_notifier = {
235 	.notifier_call = cryptomgr_notify,
236 };
237 
238 static int __init cryptomgr_init(void)
239 {
240 	return crypto_register_notifier(&cryptomgr_notifier);
241 }
242 
243 static void __exit cryptomgr_exit(void)
244 {
245 	int err = crypto_unregister_notifier(&cryptomgr_notifier);
246 	BUG_ON(err);
247 }
248 
249 /*
250  * This is arch_initcall() so that the crypto self-tests are run on algorithms
251  * registered early by subsys_initcall().  subsys_initcall() is needed for
252  * generic implementations so that they're available for comparison tests when
253  * other implementations are registered later by module_init().
254  */
255 arch_initcall(cryptomgr_init);
256 module_exit(cryptomgr_exit);
257 
258 MODULE_LICENSE("GPL");
259 MODULE_DESCRIPTION("Crypto Algorithm Manager");
260