xref: /openbmc/linux/crypto/algboss.c (revision da7f033ddc9fdebb3223b0bf88a2a2ab5b797608)
1 /*
2  * Create default crypto algorithm instances.
3  *
4  * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <linux/crypto.h>
14 #include <linux/ctype.h>
15 #include <linux/err.h>
16 #include <linux/init.h>
17 #include <linux/kthread.h>
18 #include <linux/module.h>
19 #include <linux/notifier.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/sched.h>
22 #include <linux/string.h>
23 
24 #include "internal.h"
25 
26 struct cryptomgr_param {
27 	struct rtattr *tb[CRYPTO_MAX_ATTRS + 2];
28 
29 	struct {
30 		struct rtattr attr;
31 		struct crypto_attr_type data;
32 	} type;
33 
34 	union {
35 		struct rtattr attr;
36 		struct {
37 			struct rtattr attr;
38 			struct crypto_attr_alg data;
39 		} alg;
40 		struct {
41 			struct rtattr attr;
42 			struct crypto_attr_u32 data;
43 		} nu32;
44 	} attrs[CRYPTO_MAX_ATTRS];
45 
46 	char larval[CRYPTO_MAX_ALG_NAME];
47 	char template[CRYPTO_MAX_ALG_NAME];
48 };
49 
50 static int cryptomgr_probe(void *data)
51 {
52 	struct cryptomgr_param *param = data;
53 	struct crypto_template *tmpl;
54 	struct crypto_instance *inst;
55 	int err;
56 
57 	tmpl = crypto_lookup_template(param->template);
58 	if (!tmpl)
59 		goto err;
60 
61 	do {
62 		inst = tmpl->alloc(param->tb);
63 		if (IS_ERR(inst))
64 			err = PTR_ERR(inst);
65 		else if ((err = crypto_register_instance(tmpl, inst)))
66 			tmpl->free(inst);
67 	} while (err == -EAGAIN && !signal_pending(current));
68 
69 	crypto_tmpl_put(tmpl);
70 
71 	if (err)
72 		goto err;
73 
74 out:
75 	kfree(param);
76 	module_put_and_exit(0);
77 
78 err:
79 	crypto_larval_error(param->larval, param->type.data.type,
80 			    param->type.data.mask);
81 	goto out;
82 }
83 
84 static int cryptomgr_schedule_probe(struct crypto_larval *larval)
85 {
86 	struct task_struct *thread;
87 	struct cryptomgr_param *param;
88 	const char *name = larval->alg.cra_name;
89 	const char *p;
90 	unsigned int len;
91 	int i;
92 
93 	if (!try_module_get(THIS_MODULE))
94 		goto err;
95 
96 	param = kzalloc(sizeof(*param), GFP_KERNEL);
97 	if (!param)
98 		goto err_put_module;
99 
100 	for (p = name; isalnum(*p) || *p == '-' || *p == '_'; p++)
101 		;
102 
103 	len = p - name;
104 	if (!len || *p != '(')
105 		goto err_free_param;
106 
107 	memcpy(param->template, name, len);
108 
109 	i = 0;
110 	for (;;) {
111 		int notnum = 0;
112 
113 		name = ++p;
114 		len = 0;
115 
116 		for (; isalnum(*p) || *p == '-' || *p == '_'; p++)
117 			notnum |= !isdigit(*p);
118 
119 		if (*p == '(') {
120 			int recursion = 0;
121 
122 			for (;;) {
123 				if (!*++p)
124 					goto err_free_param;
125 				if (*p == '(')
126 					recursion++;
127 				else if (*p == ')' && !recursion--)
128 					break;
129 			}
130 
131 			notnum = 1;
132 			p++;
133 		}
134 
135 		len = p - name;
136 		if (!len)
137 			goto err_free_param;
138 
139 		if (notnum) {
140 			param->attrs[i].alg.attr.rta_len =
141 				sizeof(param->attrs[i].alg);
142 			param->attrs[i].alg.attr.rta_type = CRYPTOA_ALG;
143 			memcpy(param->attrs[i].alg.data.name, name, len);
144 		} else {
145 			param->attrs[i].nu32.attr.rta_len =
146 				sizeof(param->attrs[i].nu32);
147 			param->attrs[i].nu32.attr.rta_type = CRYPTOA_U32;
148 			param->attrs[i].nu32.data.num =
149 				simple_strtol(name, NULL, 0);
150 		}
151 
152 		param->tb[i + 1] = &param->attrs[i].attr;
153 		i++;
154 
155 		if (i >= CRYPTO_MAX_ATTRS)
156 			goto err_free_param;
157 
158 		if (*p == ')')
159 			break;
160 
161 		if (*p != ',')
162 			goto err_free_param;
163 	}
164 
165 	if (!i)
166 		goto err_free_param;
167 
168 	param->tb[i + 1] = NULL;
169 
170 	param->type.attr.rta_len = sizeof(param->type);
171 	param->type.attr.rta_type = CRYPTOA_TYPE;
172 	param->type.data.type = larval->alg.cra_flags;
173 	param->type.data.mask = larval->mask;
174 	param->tb[0] = &param->type.attr;
175 
176 	memcpy(param->larval, larval->alg.cra_name, CRYPTO_MAX_ALG_NAME);
177 
178 	thread = kthread_run(cryptomgr_probe, param, "cryptomgr");
179 	if (IS_ERR(thread))
180 		goto err_free_param;
181 
182 	return NOTIFY_STOP;
183 
184 err_free_param:
185 	kfree(param);
186 err_put_module:
187 	module_put(THIS_MODULE);
188 err:
189 	return NOTIFY_OK;
190 }
191 
192 static int cryptomgr_notify(struct notifier_block *this, unsigned long msg,
193 			    void *data)
194 {
195 	switch (msg) {
196 	case CRYPTO_MSG_ALG_REQUEST:
197 		return cryptomgr_schedule_probe(data);
198 	}
199 
200 	return NOTIFY_DONE;
201 }
202 
203 static struct notifier_block cryptomgr_notifier = {
204 	.notifier_call = cryptomgr_notify,
205 };
206 
207 static int __init cryptomgr_init(void)
208 {
209 	int err;
210 
211 	err = testmgr_init();
212 	if (err)
213 		return err;
214 
215 	err = crypto_register_notifier(&cryptomgr_notifier);
216 	if (err)
217 		goto free_testmgr;
218 
219 	return 0;
220 
221 free_testmgr:
222 	testmgr_exit();
223 	return err;
224 }
225 
226 static void __exit cryptomgr_exit(void)
227 {
228 	int err = crypto_unregister_notifier(&cryptomgr_notifier);
229 	BUG_ON(err);
230 
231 	testmgr_exit();
232 }
233 
234 subsys_initcall(cryptomgr_init);
235 module_exit(cryptomgr_exit);
236 
237 MODULE_LICENSE("GPL");
238 MODULE_DESCRIPTION("Crypto Algorithm Manager");
239