diff options
Diffstat (limited to 'crypto/crypto_user.c')
-rw-r--r-- | crypto/crypto_user.c | 372 |
1 files changed, 372 insertions, 0 deletions
diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c new file mode 100644 index 000000000000..513cfe7bc3ba --- /dev/null +++ b/crypto/crypto_user.c | |||
@@ -0,0 +1,372 @@ | |||
1 | /* | ||
2 | * Crypto user configuration API. | ||
3 | * | ||
4 | * Copyright (C) 2011 secunet Security Networks AG | ||
5 | * Copyright (C) 2011 Steffen Klassert <steffen.klassert@secunet.com> | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify it | ||
8 | * under the terms and conditions of the GNU General Public License, | ||
9 | * version 2, as published by the Free Software Foundation. | ||
10 | * | ||
11 | * This program is distributed in the hope it will be useful, but WITHOUT | ||
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | ||
14 | * more details. | ||
15 | * | ||
16 | * You should have received a copy of the GNU General Public License along with | ||
17 | * this program; if not, write to the Free Software Foundation, Inc., | ||
18 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | ||
19 | */ | ||
20 | |||
21 | #include <linux/module.h> | ||
22 | #include <linux/crypto.h> | ||
23 | #include <linux/cryptouser.h> | ||
24 | #include <net/netlink.h> | ||
25 | #include <linux/security.h> | ||
26 | #include <net/net_namespace.h> | ||
27 | #include "internal.h" | ||
28 | |||
29 | DEFINE_MUTEX(crypto_cfg_mutex); | ||
30 | |||
31 | /* The crypto netlink socket */ | ||
32 | static struct sock *crypto_nlsk; | ||
33 | |||
34 | struct crypto_dump_info { | ||
35 | struct sk_buff *in_skb; | ||
36 | struct sk_buff *out_skb; | ||
37 | u32 nlmsg_seq; | ||
38 | u16 nlmsg_flags; | ||
39 | }; | ||
40 | |||
41 | static struct crypto_alg *crypto_alg_match(struct crypto_user_alg *p, int exact) | ||
42 | { | ||
43 | int match; | ||
44 | struct crypto_alg *q, *alg = NULL; | ||
45 | |||
46 | down_read(&crypto_alg_sem); | ||
47 | |||
48 | if (list_empty(&crypto_alg_list)) | ||
49 | return NULL; | ||
50 | |||
51 | list_for_each_entry(q, &crypto_alg_list, cra_list) { | ||
52 | |||
53 | if ((q->cra_flags ^ p->cru_type) & p->cru_mask) | ||
54 | continue; | ||
55 | |||
56 | if (strlen(p->cru_driver_name)) | ||
57 | match = !strcmp(q->cra_driver_name, | ||
58 | p->cru_driver_name); | ||
59 | else if (!exact) | ||
60 | match = !strcmp(q->cra_name, p->cru_name); | ||
61 | |||
62 | if (match) { | ||
63 | alg = q; | ||
64 | break; | ||
65 | } | ||
66 | } | ||
67 | |||
68 | up_read(&crypto_alg_sem); | ||
69 | |||
70 | return alg; | ||
71 | } | ||
72 | |||
73 | static int crypto_report_one(struct crypto_alg *alg, | ||
74 | struct crypto_user_alg *ualg, struct sk_buff *skb) | ||
75 | { | ||
76 | memcpy(&ualg->cru_name, &alg->cra_name, sizeof(ualg->cru_name)); | ||
77 | memcpy(&ualg->cru_driver_name, &alg->cra_driver_name, | ||
78 | sizeof(ualg->cru_driver_name)); | ||
79 | memcpy(&ualg->cru_module_name, module_name(alg->cra_module), | ||
80 | CRYPTO_MAX_ALG_NAME); | ||
81 | |||
82 | ualg->cru_flags = alg->cra_flags; | ||
83 | ualg->cru_refcnt = atomic_read(&alg->cra_refcnt); | ||
84 | |||
85 | NLA_PUT_U32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority); | ||
86 | |||
87 | return 0; | ||
88 | |||
89 | nla_put_failure: | ||
90 | return -EMSGSIZE; | ||
91 | } | ||
92 | |||
93 | static int crypto_report_alg(struct crypto_alg *alg, | ||
94 | struct crypto_dump_info *info) | ||
95 | { | ||
96 | struct sk_buff *in_skb = info->in_skb; | ||
97 | struct sk_buff *skb = info->out_skb; | ||
98 | struct nlmsghdr *nlh; | ||
99 | struct crypto_user_alg *ualg; | ||
100 | int err = 0; | ||
101 | |||
102 | nlh = nlmsg_put(skb, NETLINK_CB(in_skb).pid, info->nlmsg_seq, | ||
103 | CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags); | ||
104 | if (!nlh) { | ||
105 | err = -EMSGSIZE; | ||
106 | goto out; | ||
107 | } | ||
108 | |||
109 | ualg = nlmsg_data(nlh); | ||
110 | |||
111 | err = crypto_report_one(alg, ualg, skb); | ||
112 | if (err) { | ||
113 | nlmsg_cancel(skb, nlh); | ||
114 | goto out; | ||
115 | } | ||
116 | |||
117 | nlmsg_end(skb, nlh); | ||
118 | |||
119 | out: | ||
120 | return err; | ||
121 | } | ||
122 | |||
123 | static int crypto_report(struct sk_buff *in_skb, struct nlmsghdr *in_nlh, | ||
124 | struct nlattr **attrs) | ||
125 | { | ||
126 | struct crypto_user_alg *p = nlmsg_data(in_nlh); | ||
127 | struct crypto_alg *alg; | ||
128 | struct sk_buff *skb; | ||
129 | struct crypto_dump_info info; | ||
130 | int err; | ||
131 | |||
132 | if (!p->cru_driver_name) | ||
133 | return -EINVAL; | ||
134 | |||
135 | alg = crypto_alg_match(p, 1); | ||
136 | if (!alg) | ||
137 | return -ENOENT; | ||
138 | |||
139 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); | ||
140 | if (!skb) | ||
141 | return -ENOMEM; | ||
142 | |||
143 | info.in_skb = in_skb; | ||
144 | info.out_skb = skb; | ||
145 | info.nlmsg_seq = in_nlh->nlmsg_seq; | ||
146 | info.nlmsg_flags = 0; | ||
147 | |||
148 | err = crypto_report_alg(alg, &info); | ||
149 | if (err) | ||
150 | return err; | ||
151 | |||
152 | return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).pid); | ||
153 | } | ||
154 | |||
155 | static int crypto_dump_report(struct sk_buff *skb, struct netlink_callback *cb) | ||
156 | { | ||
157 | struct crypto_alg *alg; | ||
158 | struct crypto_dump_info info; | ||
159 | int err; | ||
160 | |||
161 | if (cb->args[0]) | ||
162 | goto out; | ||
163 | |||
164 | cb->args[0] = 1; | ||
165 | |||
166 | info.in_skb = cb->skb; | ||
167 | info.out_skb = skb; | ||
168 | info.nlmsg_seq = cb->nlh->nlmsg_seq; | ||
169 | info.nlmsg_flags = NLM_F_MULTI; | ||
170 | |||
171 | list_for_each_entry(alg, &crypto_alg_list, cra_list) { | ||
172 | err = crypto_report_alg(alg, &info); | ||
173 | if (err) | ||
174 | goto out_err; | ||
175 | } | ||
176 | |||
177 | out: | ||
178 | return skb->len; | ||
179 | out_err: | ||
180 | return err; | ||
181 | } | ||
182 | |||
183 | static int crypto_dump_report_done(struct netlink_callback *cb) | ||
184 | { | ||
185 | return 0; | ||
186 | } | ||
187 | |||
188 | static int crypto_update_alg(struct sk_buff *skb, struct nlmsghdr *nlh, | ||
189 | struct nlattr **attrs) | ||
190 | { | ||
191 | struct crypto_alg *alg; | ||
192 | struct crypto_user_alg *p = nlmsg_data(nlh); | ||
193 | struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL]; | ||
194 | LIST_HEAD(list); | ||
195 | |||
196 | if (priority && !strlen(p->cru_driver_name)) | ||
197 | return -EINVAL; | ||
198 | |||
199 | alg = crypto_alg_match(p, 1); | ||
200 | if (!alg) | ||
201 | return -ENOENT; | ||
202 | |||
203 | down_write(&crypto_alg_sem); | ||
204 | |||
205 | crypto_remove_spawns(alg, &list, NULL); | ||
206 | |||
207 | if (priority) | ||
208 | alg->cra_priority = nla_get_u32(priority); | ||
209 | |||
210 | up_write(&crypto_alg_sem); | ||
211 | |||
212 | crypto_remove_final(&list); | ||
213 | |||
214 | return 0; | ||
215 | } | ||
216 | |||
217 | static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh, | ||
218 | struct nlattr **attrs) | ||
219 | { | ||
220 | struct crypto_alg *alg; | ||
221 | struct crypto_user_alg *p = nlmsg_data(nlh); | ||
222 | |||
223 | alg = crypto_alg_match(p, 1); | ||
224 | if (!alg) | ||
225 | return -ENOENT; | ||
226 | |||
227 | /* We can not unregister core algorithms such as aes-generic. | ||
228 | * We would loose the reference in the crypto_alg_list to this algorithm | ||
229 | * if we try to unregister. Unregistering such an algorithm without | ||
230 | * removing the module is not possible, so we restrict to crypto | ||
231 | * instances that are build from templates. */ | ||
232 | if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE)) | ||
233 | return -EINVAL; | ||
234 | |||
235 | if (atomic_read(&alg->cra_refcnt) != 1) | ||
236 | return -EBUSY; | ||
237 | |||
238 | return crypto_unregister_alg(alg); | ||
239 | } | ||
240 | |||
241 | static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh, | ||
242 | struct nlattr **attrs) | ||
243 | { | ||
244 | int exact; | ||
245 | const char *name; | ||
246 | struct crypto_alg *alg; | ||
247 | struct crypto_user_alg *p = nlmsg_data(nlh); | ||
248 | struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL]; | ||
249 | |||
250 | if (strlen(p->cru_driver_name)) | ||
251 | exact = 1; | ||
252 | |||
253 | if (priority && !exact) | ||
254 | return -EINVAL; | ||
255 | |||
256 | alg = crypto_alg_match(p, exact); | ||
257 | if (alg) | ||
258 | return -EEXIST; | ||
259 | |||
260 | if (strlen(p->cru_driver_name)) | ||
261 | name = p->cru_driver_name; | ||
262 | else | ||
263 | name = p->cru_name; | ||
264 | |||
265 | alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask); | ||
266 | if (IS_ERR(alg)) | ||
267 | return PTR_ERR(alg); | ||
268 | |||
269 | down_write(&crypto_alg_sem); | ||
270 | |||
271 | if (priority) | ||
272 | alg->cra_priority = nla_get_u32(priority); | ||
273 | |||
274 | up_write(&crypto_alg_sem); | ||
275 | |||
276 | crypto_mod_put(alg); | ||
277 | |||
278 | return 0; | ||
279 | } | ||
280 | |||
281 | #define MSGSIZE(type) sizeof(struct type) | ||
282 | |||
283 | static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = { | ||
284 | [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | ||
285 | [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | ||
286 | [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | ||
287 | [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg), | ||
288 | }; | ||
289 | |||
290 | static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = { | ||
291 | [CRYPTOCFGA_PRIORITY_VAL] = { .type = NLA_U32}, | ||
292 | }; | ||
293 | |||
294 | #undef MSGSIZE | ||
295 | |||
296 | static struct crypto_link { | ||
297 | int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **); | ||
298 | int (*dump)(struct sk_buff *, struct netlink_callback *); | ||
299 | int (*done)(struct netlink_callback *); | ||
300 | } crypto_dispatch[CRYPTO_NR_MSGTYPES] = { | ||
301 | [CRYPTO_MSG_NEWALG - CRYPTO_MSG_BASE] = { .doit = crypto_add_alg}, | ||
302 | [CRYPTO_MSG_DELALG - CRYPTO_MSG_BASE] = { .doit = crypto_del_alg}, | ||
303 | [CRYPTO_MSG_UPDATEALG - CRYPTO_MSG_BASE] = { .doit = crypto_update_alg}, | ||
304 | [CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE] = { .doit = crypto_report, | ||
305 | .dump = crypto_dump_report, | ||
306 | .done = crypto_dump_report_done}, | ||
307 | }; | ||
308 | |||
309 | static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) | ||
310 | { | ||
311 | struct nlattr *attrs[CRYPTOCFGA_MAX+1]; | ||
312 | struct crypto_link *link; | ||
313 | int type, err; | ||
314 | |||
315 | type = nlh->nlmsg_type; | ||
316 | if (type > CRYPTO_MSG_MAX) | ||
317 | return -EINVAL; | ||
318 | |||
319 | type -= CRYPTO_MSG_BASE; | ||
320 | link = &crypto_dispatch[type]; | ||
321 | |||
322 | if (security_netlink_recv(skb, CAP_NET_ADMIN)) | ||
323 | return -EPERM; | ||
324 | |||
325 | if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) && | ||
326 | (nlh->nlmsg_flags & NLM_F_DUMP))) { | ||
327 | if (link->dump == NULL) | ||
328 | return -EINVAL; | ||
329 | |||
330 | return netlink_dump_start(crypto_nlsk, skb, nlh, | ||
331 | link->dump, link->done, 0); | ||
332 | } | ||
333 | |||
334 | err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX, | ||
335 | crypto_policy); | ||
336 | if (err < 0) | ||
337 | return err; | ||
338 | |||
339 | if (link->doit == NULL) | ||
340 | return -EINVAL; | ||
341 | |||
342 | return link->doit(skb, nlh, attrs); | ||
343 | } | ||
344 | |||
345 | static void crypto_netlink_rcv(struct sk_buff *skb) | ||
346 | { | ||
347 | mutex_lock(&crypto_cfg_mutex); | ||
348 | netlink_rcv_skb(skb, &crypto_user_rcv_msg); | ||
349 | mutex_unlock(&crypto_cfg_mutex); | ||
350 | } | ||
351 | |||
352 | static int __init crypto_user_init(void) | ||
353 | { | ||
354 | crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, | ||
355 | 0, crypto_netlink_rcv, | ||
356 | NULL, THIS_MODULE); | ||
357 | if (!crypto_nlsk) | ||
358 | return -ENOMEM; | ||
359 | |||
360 | return 0; | ||
361 | } | ||
362 | |||
363 | static void __exit crypto_user_exit(void) | ||
364 | { | ||
365 | netlink_kernel_release(crypto_nlsk); | ||
366 | } | ||
367 | |||
368 | module_init(crypto_user_init); | ||
369 | module_exit(crypto_user_exit); | ||
370 | MODULE_LICENSE("GPL"); | ||
371 | MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>"); | ||
372 | MODULE_DESCRIPTION("Crypto userspace configuration API"); | ||