[net-next-2.6.git] / net / rxrpc / ar-key.c

/* RxRPC key management
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 * RxRPC keys should have a description of describing their purpose:
 *	"afs@CAMBRIDGE.REDHAT.COM>
 */

#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/key.h>
#include <linux/crypto.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <keys/rxrpc-type.h>
#include <keys/user-type.h>
#include "ar-internal.h"

static int rxrpc_instantiate(struct key *, const void *, size_t);
static int rxrpc_instantiate_s(struct key *, const void *, size_t);
static void rxrpc_destroy(struct key *);
static void rxrpc_destroy_s(struct key *);
static void rxrpc_describe(const struct key *, struct seq_file *);

/*
 * rxrpc defined keys take an arbitrary string as the description and an
 * arbitrary blob of data as the payload
 */
struct key_type key_type_rxrpc = {
	.name		= "rxrpc",
	.instantiate	= rxrpc_instantiate,
	.match		= user_match,
	.destroy	= rxrpc_destroy,
	.describe	= rxrpc_describe,
};

EXPORT_SYMBOL(key_type_rxrpc);

/*
 * rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
 * description and an 8-byte decryption key as the payload
 */
struct key_type key_type_rxrpc_s = {
	.name		= "rxrpc_s",
	.instantiate	= rxrpc_instantiate_s,
	.match		= user_match,
	.destroy	= rxrpc_destroy_s,
	.describe	= rxrpc_describe,
};

/*
 * instantiate an rxrpc defined key
 * data should be of the form:
 *	OFFSET	LEN	CONTENT
 *	0	4	key interface version number
 *	4	2	security index (type)
 *	6	2	ticket length
 *	8	4	key expiry time (time_t)
 *	12	4	kvno
 *	16	8	session key
 *	24	[len]	ticket
 *
 * if no data is provided, then a no-security key is made
 */
static int rxrpc_instantiate(struct key *key, const void *data, size_t datalen)
{
	const struct rxkad_key *tsec;
	struct rxrpc_key_payload *upayload;
	size_t plen;
	u32 kver;
	int ret;

	_enter("{%x},,%zu", key_serial(key), datalen);

	/* handle a no-security key */
	if (!data && datalen == 0)
		return 0;

	/* get the key interface version number */
	ret = -EINVAL;
	if (datalen <= 4 || !data)
		goto error;
	memcpy(&kver, data, sizeof(kver));
	data += sizeof(kver);
	datalen -= sizeof(kver);

	_debug("KEY I/F VERSION: %u", kver);

	ret = -EKEYREJECTED;
	if (kver != 1)
		goto error;

	/* deal with a version 1 key */
	ret = -EINVAL;
	if (datalen < sizeof(*tsec))
		goto error;

	tsec = data;
	if (datalen != sizeof(*tsec) + tsec->ticket_len)
		goto error;

	_debug("SCIX: %u", tsec->security_index);
	_debug("TLEN: %u", tsec->ticket_len);
	_debug("EXPY: %x", tsec->expiry);
	_debug("KVNO: %u", tsec->kvno);
	_debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
	       tsec->session_key[0], tsec->session_key[1],
	       tsec->session_key[2], tsec->session_key[3],
	       tsec->session_key[4], tsec->session_key[5],
	       tsec->session_key[6], tsec->session_key[7]);
	if (tsec->ticket_len >= 8)
		_debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
		       tsec->ticket[0], tsec->ticket[1],
		       tsec->ticket[2], tsec->ticket[3],
		       tsec->ticket[4], tsec->ticket[5],
		       tsec->ticket[6], tsec->ticket[7]);

	ret = -EPROTONOSUPPORT;
	if (tsec->security_index != 2)
		goto error;

	key->type_data.x[0] = tsec->security_index;

	plen = sizeof(*upayload) + tsec->ticket_len;
	ret = key_payload_reserve(key, plen);
	if (ret < 0)
		goto error;

	ret = -ENOMEM;
	upayload = kmalloc(plen, GFP_KERNEL);
	if (!upayload)
		goto error;

	/* attach the data */
	memcpy(&upayload->k, tsec, sizeof(*tsec));
	memcpy(&upayload->k.ticket, (void *)tsec + sizeof(*tsec),
	       tsec->ticket_len);
	key->payload.data = upayload;
	key->expiry = tsec->expiry;
	ret = 0;

error:
	return ret;
}

/*
 * instantiate a server secret key
 * data should be a pointer to the 8-byte secret key
 */
static int rxrpc_instantiate_s(struct key *key, const void *data,
			       size_t datalen)
{
	struct crypto_blkcipher *ci;

	_enter("{%x},,%zu", key_serial(key), datalen);

	if (datalen != 8)
		return -EINVAL;

	memcpy(&key->type_data, data, 8);

	ci = crypto_alloc_blkcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
	if (IS_ERR(ci)) {
		_leave(" = %ld", PTR_ERR(ci));
		return PTR_ERR(ci);
	}

	if (crypto_blkcipher_setkey(ci, data, 8) < 0)
		BUG();

	key->payload.data = ci;
	_leave(" = 0");
	return 0;
}

/*
 * dispose of the data dangling from the corpse of a rxrpc key
 */
static void rxrpc_destroy(struct key *key)
{
	kfree(key->payload.data);
}

/*
 * dispose of the data dangling from the corpse of a rxrpc key
 */
static void rxrpc_destroy_s(struct key *key)
{
	if (key->payload.data) {
		crypto_free_blkcipher(key->payload.data);
		key->payload.data = NULL;
	}
}

/*
 * describe the rxrpc key
 */
static void rxrpc_describe(const struct key *key, struct seq_file *m)
{
	seq_puts(m, key->description);
}

/*
 * grab the security key for a socket
 */
int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen)
{
	struct key *key;
	char *description;

	_enter("");

	if (optlen <= 0 || optlen > PAGE_SIZE - 1)
		return -EINVAL;

	description = kmalloc(optlen + 1, GFP_KERNEL);
	if (!description)
		return -ENOMEM;

	if (copy_from_user(description, optval, optlen)) {
		kfree(description);
		return -EFAULT;
	}
	description[optlen] = 0;

	key = request_key(&key_type_rxrpc, description, NULL);
	if (IS_ERR(key)) {
		kfree(description);
		_leave(" = %ld", PTR_ERR(key));
		return PTR_ERR(key);
	}

	rx->key = key;
	kfree(description);
	_leave(" = 0 [key %x]", key->serial);
	return 0;
}

/*
 * grab the security keyring for a server socket
 */
int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval,
			 int optlen)
{
	struct key *key;
	char *description;

	_enter("");

	if (optlen <= 0 || optlen > PAGE_SIZE - 1)
		return -EINVAL;

	description = kmalloc(optlen + 1, GFP_KERNEL);
	if (!description)
		return -ENOMEM;

	if (copy_from_user(description, optval, optlen)) {
		kfree(description);
		return -EFAULT;
	}
	description[optlen] = 0;

	key = request_key(&key_type_keyring, description, NULL);
	if (IS_ERR(key)) {
		kfree(description);
		_leave(" = %ld", PTR_ERR(key));
		return PTR_ERR(key);
	}

	rx->securities = key;
	kfree(description);
	_leave(" = 0 [key %x]", key->serial);
	return 0;
}

/*
 * generate a server data key
 */
int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
			      const void *session_key,
			      time_t expiry,
			      u32 kvno)
{
	struct key *key;
	int ret;

	struct {
		u32 kver;
		struct rxkad_key tsec;
	} data;

	_enter("");

	key = key_alloc(&key_type_rxrpc, "x", 0, 0, current, 0,
			KEY_ALLOC_NOT_IN_QUOTA);
	if (IS_ERR(key)) {
		_leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
		return -ENOMEM;
	}

	_debug("key %d", key_serial(key));

	data.kver = 1;
	data.tsec.security_index = 2;
	data.tsec.ticket_len = 0;
	data.tsec.expiry = expiry;
	data.tsec.kvno = 0;

	memcpy(&data.tsec.session_key, session_key,
	       sizeof(data.tsec.session_key));

	ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
	if (ret < 0)
		goto error;

	conn->key = key;
	_leave(" = 0 [%d]", key_serial(key));
	return 0;

error:
	key_revoke(key);
	key_put(key);
	_leave(" = -ENOMEM [ins %d]", ret);
	return -ENOMEM;
}

EXPORT_SYMBOL(rxrpc_get_server_data_key);
Commit	Line	Data
17926a79 DH	1	/* RxRPC key management
	2	*
	3	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*
	11	* RxRPC keys should have a description of describing their purpose:
	12	* "afs@CAMBRIDGE.REDHAT.COM>
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/net.h>
	17	#include <linux/skbuff.h>
	18	#include <linux/key.h>
	19	#include <linux/crypto.h>
	20	#include <net/sock.h>
	21	#include <net/af_rxrpc.h>
	22	#include <keys/rxrpc-type.h>
	23	#include <keys/user-type.h>
	24	#include "ar-internal.h"
	25
	26	static int rxrpc_instantiate(struct key , const void , size_t);
	27	static int rxrpc_instantiate_s(struct key , const void , size_t);
	28	static void rxrpc_destroy(struct key *);
	29	static void rxrpc_destroy_s(struct key *);
	30	static void rxrpc_describe(const struct key , struct seq_file );
	31
	32	/*
	33	* rxrpc defined keys take an arbitrary string as the description and an
	34	* arbitrary blob of data as the payload
	35	*/
	36	struct key_type key_type_rxrpc = {
	37	.name = "rxrpc",
	38	.instantiate = rxrpc_instantiate,
	39	.match = user_match,
	40	.destroy = rxrpc_destroy,
	41	.describe = rxrpc_describe,
	42	};
	43
	44	EXPORT_SYMBOL(key_type_rxrpc);
	45
	46	/*
	47	* rxrpc server defined keys take "<serviceId>:<securityIndex>" as the
	48	* description and an 8-byte decryption key as the payload
	49	*/
	50	struct key_type key_type_rxrpc_s = {
	51	.name = "rxrpc_s",
	52	.instantiate = rxrpc_instantiate_s,
	53	.match = user_match,
	54	.destroy = rxrpc_destroy_s,
	55	.describe = rxrpc_describe,
	56	};
	57
	58	/*
	59	* instantiate an rxrpc defined key
	60	* data should be of the form:
	61	* OFFSET LEN CONTENT
	62	* 0 4 key interface version number
	63	* 4 2 security index (type)
	64	* 6 2 ticket length
65	* 8 4 key expiry time (time_t)
66	* 12 4 kvno
67	* 16 8 session key
68	* 24 [len] ticket
69	*
70	* if no data is provided, then a no-security key is made
71	*/
72	static int rxrpc_instantiate(struct key key, const void data, size_t datalen)
73	{
74	const struct rxkad_key *tsec;
75	struct rxrpc_key_payload *upayload;
76	size_t plen;
77	u32 kver;
78	int ret;
79
80	_enter("{%x},,%zu", key_serial(key), datalen);
81
82	/* handle a no-security key */
83	if (!data && datalen == 0)
84	return 0;
85
86	/* get the key interface version number */
87	ret = -EINVAL;
88	if (datalen <= 4 \|\| !data)
89	goto error;
90	memcpy(&kver, data, sizeof(kver));
91	data += sizeof(kver);
92	datalen -= sizeof(kver);
93
94	_debug("KEY I/F VERSION: %u", kver);
95
96	ret = -EKEYREJECTED;
97	if (kver != 1)
98	goto error;
99
100	/* deal with a version 1 key */
101	ret = -EINVAL;
102	if (datalen < sizeof(*tsec))
103	goto error;
104
105	tsec = data;
106	if (datalen != sizeof(*tsec) + tsec->ticket_len)
107	goto error;
108
109	_debug("SCIX: %u", tsec->security_index);
110	_debug("TLEN: %u", tsec->ticket_len);
111	_debug("EXPY: %x", tsec->expiry);
112	_debug("KVNO: %u", tsec->kvno);
113	_debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
114	tsec->session_key[0], tsec->session_key[1],
115	tsec->session_key[2], tsec->session_key[3],
116	tsec->session_key[4], tsec->session_key[5],
117	tsec->session_key[6], tsec->session_key[7]);
118	if (tsec->ticket_len >= 8)
119	_debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
120	tsec->ticket[0], tsec->ticket[1],
121	tsec->ticket[2], tsec->ticket[3],
122	tsec->ticket[4], tsec->ticket[5],
123	tsec->ticket[6], tsec->ticket[7]);
124
125	ret = -EPROTONOSUPPORT;
126	if (tsec->security_index != 2)
127	goto error;
128
129	key->type_data.x[0] = tsec->security_index;
130
131	plen = sizeof(*upayload) + tsec->ticket_len;
132	ret = key_payload_reserve(key, plen);
133	if (ret < 0)
134	goto error;
135
136	ret = -ENOMEM;
137	upayload = kmalloc(plen, GFP_KERNEL);
138	if (!upayload)
139	goto error;
140
141	/* attach the data */
142	memcpy(&upayload->k, tsec, sizeof(*tsec));
143	memcpy(&upayload->k.ticket, (void )tsec + sizeof(tsec),
144	tsec->ticket_len);
145	key->payload.data = upayload;
146	key->expiry = tsec->expiry;
147	ret = 0;
148
149	error:
150	return ret;
151	}
152
153	/*
154	* instantiate a server secret key
155	* data should be a pointer to the 8-byte secret key
156	*/
157	static int rxrpc_instantiate_s(struct key key, const void data,
158	size_t datalen)
159	{
160	struct crypto_blkcipher *ci;
161
162	_enter("{%x},,%zu", key_serial(key), datalen);
163
164	if (datalen != 8)
165	return -EINVAL;
166
167	memcpy(&key->type_data, data, 8);
168
169	ci = crypto_alloc_blkcipher("pcbc(des)", 0, CRYPTO_ALG_ASYNC);
170	if (IS_ERR(ci)) {
171	_leave(" = %ld", PTR_ERR(ci));
172	return PTR_ERR(ci);
173	}
174
175	if (crypto_blkcipher_setkey(ci, data, 8) < 0)
176	BUG();
177
178	key->payload.data = ci;
179	_leave(" = 0");
180	return 0;
181	}
182
183	/*
184	* dispose of the data dangling from the corpse of a rxrpc key
185	*/
186	static void rxrpc_destroy(struct key *key)
187	{
188	kfree(key->payload.data);
189	}
190
191	/*
192	* dispose of the data dangling from the corpse of a rxrpc key
193	*/
194	static void rxrpc_destroy_s(struct key *key)
195	{
196	if (key->payload.data) {
197	crypto_free_blkcipher(key->payload.data);
198	key->payload.data = NULL;
199	}
200	}
201
202	/*
203	* describe the rxrpc key
204	*/
205	static void rxrpc_describe(const struct key key, struct seq_file m)
206	{
207	seq_puts(m, key->description);
208	}
209
210	/*
211	* grab the security key for a socket
212	*/
213	int rxrpc_request_key(struct rxrpc_sock rx, char __user optval, int optlen)
214	{
215	struct key *key;
216	char *description;
217
218	_enter("");
219
220	if (optlen <= 0 \|\| optlen > PAGE_SIZE - 1)
221	return -EINVAL;
222
223	description = kmalloc(optlen + 1, GFP_KERNEL);
224	if (!description)
225	return -ENOMEM;
226
227	if (copy_from_user(description, optval, optlen)) {
228	kfree(description);
229	return -EFAULT;
230	}
231	description[optlen] = 0;
232
233	key = request_key(&key_type_rxrpc, description, NULL);
234	if (IS_ERR(key)) {
235	kfree(description);
236	_leave(" = %ld", PTR_ERR(key));
237	return PTR_ERR(key);
238	}
239
240	rx->key = key;
241	kfree(description);
242	_leave(" = 0 [key %x]", key->serial);
243	return 0;
244	}
245
246	/*
247	* grab the security keyring for a server socket
248	*/
249	int rxrpc_server_keyring(struct rxrpc_sock rx, char __user optval,
250	int optlen)
251	{
252	struct key *key;
253	char *description;
254
255	_enter("");
256
257	if (optlen <= 0 \|\| optlen > PAGE_SIZE - 1)
258	return -EINVAL;
259
260	description = kmalloc(optlen + 1, GFP_KERNEL);
261	if (!description)
262	return -ENOMEM;
263
264	if (copy_from_user(description, optval, optlen)) {
265	kfree(description);
266	return -EFAULT;
267	}
268	description[optlen] = 0;
269
270	key = request_key(&key_type_keyring, description, NULL);
271	if (IS_ERR(key)) {
272	kfree(description);
273	_leave(" = %ld", PTR_ERR(key));
274	return PTR_ERR(key);
275	}
276
277	rx->securities = key;
278	kfree(description);
279	_leave(" = 0 [key %x]", key->serial);
280	return 0;
281	}
282
283	/*
284	* generate a server data key
285	*/
286	int rxrpc_get_server_data_key(struct rxrpc_connection *conn,
287	const void *session_key,
288	time_t expiry,
289	u32 kvno)
290	{
291	struct key *key;
292	int ret;
293
294	struct {
295	u32 kver;
296	struct rxkad_key tsec;
297	} data;
298
299	_enter("");
300
301	key = key_alloc(&key_type_rxrpc, "x", 0, 0, current, 0,
302	KEY_ALLOC_NOT_IN_QUOTA);
303	if (IS_ERR(key)) {
304	_leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
305	return -ENOMEM;
306	}
307
308	_debug("key %d", key_serial(key));
309
310	data.kver = 1;
311	data.tsec.security_index = 2;
312	data.tsec.ticket_len = 0;
313	data.tsec.expiry = expiry;
314	data.tsec.kvno = 0;
315
316	memcpy(&data.tsec.session_key, session_key,
317	sizeof(data.tsec.session_key));
318
319	ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
320	if (ret < 0)
321	goto error;
322
323	conn->key = key;
324	_leave(" = 0 [%d]", key_serial(key));
325	return 0;
326
327	error:
328	key_revoke(key);
329	key_put(key);
330	_leave(" = -ENOMEM [ins %d]", ret);
331	return -ENOMEM;
332	}
333
334	EXPORT_SYMBOL(rxrpc_get_server_data_key);