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
23struct 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
44struct crypto_test_param {
45	char driver[CRYPTO_MAX_ALG_NAME];
46	char alg[CRYPTO_MAX_ALG_NAME];
47	u32 type;
48};
49
50static 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
66out:
67	complete_all(&param->larval->completion);
68	crypto_alg_put(&param->larval->alg);
69	kfree(param);
70	module_put_and_kthread_exit(0);
71}
72
73static 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
164err_put_larval:
165	crypto_alg_put(&larval->alg);
166err_free_param:
167	kfree(param);
168err_put_module:
169	module_put(THIS_MODULE);
170err:
171	return NOTIFY_OK;
172}
173
174static int cryptomgr_test(void *data)
175{
176	struct crypto_test_param *param = data;
177	u32 type = param->type;
178	int err;
179
180	err = alg_test(param->driver, param->alg, type, CRYPTO_ALG_TESTED);
181
182	crypto_alg_tested(param->driver, err);
183
184	kfree(param);
185	module_put_and_kthread_exit(0);
186}
187
188static int cryptomgr_schedule_test(struct crypto_alg *alg)
189{
190	struct task_struct *thread;
191	struct crypto_test_param *param;
192
193	if (IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS))
194		return NOTIFY_DONE;
195
196	if (!try_module_get(THIS_MODULE))
197		goto err;
198
199	param = kzalloc(sizeof(*param), GFP_KERNEL);
200	if (!param)
201		goto err_put_module;
202
203	memcpy(param->driver, alg->cra_driver_name, sizeof(param->driver));
204	memcpy(param->alg, alg->cra_name, sizeof(param->alg));
205	param->type = alg->cra_flags;
206
207	thread = kthread_run(cryptomgr_test, param, "cryptomgr_test");
208	if (IS_ERR(thread))
209		goto err_free_param;
210
211	return NOTIFY_STOP;
212
213err_free_param:
214	kfree(param);
215err_put_module:
216	module_put(THIS_MODULE);
217err:
218	return NOTIFY_OK;
219}
220
221static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
222			    void *data)
223{
224	switch (msg) {
225	case CRYPTO_MSG_ALG_REQUEST:
226		return cryptomgr_schedule_probe(data);
227	case CRYPTO_MSG_ALG_REGISTER:
228		return cryptomgr_schedule_test(data);
229	case CRYPTO_MSG_ALG_LOADED:
230		break;
231	}
232
233	return NOTIFY_DONE;
234}
235
236static struct notifier_block cryptomgr_notifier = {
237	.notifier_call = cryptomgr_notify,
238};
239
240static int __init cryptomgr_init(void)
241{
242	return crypto_register_notifier(&cryptomgr_notifier);
243}
244
245static void __exit cryptomgr_exit(void)
246{
247	int err = crypto_unregister_notifier(&cryptomgr_notifier);
248	BUG_ON(err);
249}
250
251/*
252 * This is arch_initcall() so that the crypto self-tests are run on algorithms
253 * registered early by subsys_initcall().  subsys_initcall() is needed for
254 * generic implementations so that they're available for comparison tests when
255 * other implementations are registered later by module_init().
256 */
257arch_initcall(cryptomgr_init);
258module_exit(cryptomgr_exit);
259
260MODULE_LICENSE("GPL");
261MODULE_DESCRIPTION("Crypto Algorithm Manager");
262