xref: /openbmc/linux/crypto/algboss.c (revision 48cc39c3) 
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 	complete_all(&param->larval->completion);
68 	crypto_alg_put(&param->larval->alg);
69 	kfree(param);
70 	module_put_and_exit(0);
71 }
72 
73 static int cryptomgr_schedule_probe(struct crypto_larval *larval)
74 {
75 	struct task_struct *thread;
76 	struct cryptomgr_param *param;
77 	const char *name = larval->alg.cra_name;
78 	const char *p;
79 	unsigned int len;
80 	int i;
81 
82 	if (!try_module_get(THIS_MODULE))
83 		goto err;
84 
85 	param = kzalloc(sizeof(*param), GFP_KERNEL);
86 	if (!param)
87 		goto err_put_module;
88 
89 	for (p = name; isalnum(*p) || *p == '-' || *p == '_'; p++)
90 		;
91 
92 	len = p - name;
93 	if (!len || *p != '(')
94 		goto err_free_param;
95 
96 	memcpy(param->template, name, len);
97 
98 	i = 0;
99 	for (;;) {
100 		name = ++p;
101 
102 		for (; isalnum(*p) || *p == '-' || *p == '_'; p++)
103 			;
104 
105 		if (*p == '(') {
106 			int recursion = 0;
107 
108 			for (;;) {
109 				if (!*++p)
110 					goto err_free_param;
111 				if (*p == '(')
112 					recursion++;
113 				else if (*p == ')' && !recursion--)
114 					break;
115 			}
116 
117 			p++;
118 		}
119 
120 		len = p - name;
121 		if (!len)
122 			goto err_free_param;
123 
124 		param->attrs[i].attr.rta_len = sizeof(param->attrs[i]);
125 		param->attrs[i].attr.rta_type = CRYPTOA_ALG;
126 		memcpy(param->attrs[i].data.name, name, len);
127 
128 		param->tb[i + 1] = &param->attrs[i].attr;
129 		i++;
130 
131 		if (i >= CRYPTO_MAX_ATTRS)
132 			goto err_free_param;
133 
134 		if (*p == ')')
135 			break;
136 
137 		if (*p != ',')
138 			goto err_free_param;
139 	}
140 
141 	if (!i)
142 		goto err_free_param;
143 
144 	param->tb[i + 1] = NULL;
145 
146 	param->type.attr.rta_len = sizeof(param->type);
147 	param->type.attr.rta_type = CRYPTOA_TYPE;
148 	param->type.data.type = larval->alg.cra_flags & ~CRYPTO_ALG_TESTED;
149 	param->type.data.mask = larval->mask & ~CRYPTO_ALG_TESTED;
150 	param->tb[0] = &param->type.attr;
151 
152 	param->otype = larval->alg.cra_flags;
153 	param->omask = larval->mask;
154 
155 	crypto_alg_get(&larval->alg);
156 	param->larval = larval;
157 
158 	thread = kthread_run(cryptomgr_probe, param, "cryptomgr_probe");
159 	if (IS_ERR(thread))
160 		goto err_put_larval;
161 
162 	return NOTIFY_STOP;
163 
164 err_put_larval:
165 	crypto_alg_put(&larval->alg);
166 err_free_param:
167 	kfree(param);
168 err_put_module:
169 	module_put(THIS_MODULE);
170 err:
171 	return NOTIFY_OK;
172 }
173 
174 static int cryptomgr_test(void *data)
175 {
176 	struct crypto_test_param *param = data;
177 	u32 type = param->type;
178 	int err = 0;
179 
180 #ifdef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
181 	goto skiptest;
182 #endif
183 
184 	if (type & CRYPTO_ALG_TESTED)
185 		goto skiptest;
186 
187 	err = alg_test(param->driver, param->alg, type, CRYPTO_ALG_TESTED);
188 
189 skiptest:
190 	crypto_alg_tested(param->driver, err);
191 
192 	kfree(param);
193 	module_put_and_exit(0);
194 }
195 
196 static int cryptomgr_schedule_test(struct crypto_alg *alg)
197 {
198 	struct task_struct *thread;
199 	struct crypto_test_param *param;
200 	u32 type;
201 
202 	if (!try_module_get(THIS_MODULE))
203 		goto err;
204 
205 	param = kzalloc(sizeof(*param), GFP_KERNEL);
206 	if (!param)
207 		goto err_put_module;
208 
209 	memcpy(param->driver, alg->cra_driver_name, sizeof(param->driver));
210 	memcpy(param->alg, alg->cra_name, sizeof(param->alg));
211 	type = alg->cra_flags;
212 
213 	/* Do not test internal algorithms. */
214 	if (type & CRYPTO_ALG_INTERNAL)
215 		type |= CRYPTO_ALG_TESTED;
216 
217 	param->type = type;
218 
219 	thread = kthread_run(cryptomgr_test, param, "cryptomgr_test");
220 	if (IS_ERR(thread))
221 		goto err_free_param;
222 
223 	return NOTIFY_STOP;
224 
225 err_free_param:
226 	kfree(param);
227 err_put_module:
228 	module_put(THIS_MODULE);
229 err:
230 	return NOTIFY_OK;
231 }
232 
233 static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
234 			    void *data)
235 {
236 	switch (msg) {
237 	case CRYPTO_MSG_ALG_REQUEST:
238 		return cryptomgr_schedule_probe(data);
239 	case CRYPTO_MSG_ALG_REGISTER:
240 		return cryptomgr_schedule_test(data);
241 	case CRYPTO_MSG_ALG_LOADED:
242 		break;
243 	}
244 
245 	return NOTIFY_DONE;
246 }
247 
248 static struct notifier_block cryptomgr_notifier = {
249 	.notifier_call = cryptomgr_notify,
250 };
251 
252 static int __init cryptomgr_init(void)
253 {
254 	return crypto_register_notifier(&cryptomgr_notifier);
255 }
256 
257 static void __exit cryptomgr_exit(void)
258 {
259 	int err = crypto_unregister_notifier(&cryptomgr_notifier);
260 	BUG_ON(err);
261 }
262 
263 /*
264  * This is arch_initcall() so that the crypto self-tests are run on algorithms
265  * registered early by subsys_initcall().  subsys_initcall() is needed for
266  * generic implementations so that they're available for comparison tests when
267  * other implementations are registered later by module_init().
268  */
269 arch_initcall(cryptomgr_init);
270 module_exit(cryptomgr_exit);
271 
272 MODULE_LICENSE("GPL");
273 MODULE_DESCRIPTION("Crypto Algorithm Manager");
274