summaryrefslogtreecommitdiff
path: root/net/rxrpc/security.c
blob: 209f2c25a0da9fd48f2d8b5fd279ad0a15cd7ad2 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
// SPDX-License-Identifier: GPL-2.0-or-later
/* RxRPC security handling
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

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

static const struct rxrpc_security *rxrpc_security_types[] = {
	[RXRPC_SECURITY_NONE]	= &rxrpc_no_security,
#ifdef CONFIG_RXKAD
	[RXRPC_SECURITY_RXKAD]	= &rxkad,
#endif
};

int __init rxrpc_init_security(void)
{
	int i, ret;

	for (i = 0; i < ARRAY_SIZE(rxrpc_security_types); i++) {
		if (rxrpc_security_types[i]) {
			ret = rxrpc_security_types[i]->init();
			if (ret < 0)
				goto failed;
		}
	}

	return 0;

failed:
	for (i--; i >= 0; i--)
		if (rxrpc_security_types[i])
			rxrpc_security_types[i]->exit();
	return ret;
}

void rxrpc_exit_security(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(rxrpc_security_types); i++)
		if (rxrpc_security_types[i])
			rxrpc_security_types[i]->exit();
}

/*
 * look up an rxrpc security module
 */
const struct rxrpc_security *rxrpc_security_lookup(u8 security_index)
{
	if (security_index >= ARRAY_SIZE(rxrpc_security_types))
		return NULL;
	return rxrpc_security_types[security_index];
}

/*
 * Initialise the security on a client call.
 */
int rxrpc_init_client_call_security(struct rxrpc_call *call)
{
	const struct rxrpc_security *sec;
	struct rxrpc_key_token *token;
	struct key *key = call->key;
	int ret;

	if (!key)
		return 0;

	ret = key_validate(key);
	if (ret < 0)
		return ret;

	for (token = key->payload.data[0]; token; token = token->next) {
		sec = rxrpc_security_lookup(token->security_index);
		if (sec)
			goto found;
	}
	return -EKEYREJECTED;

found:
	call->security = sec;
	_leave(" = 0");
	return 0;
}

/*
 * initialise the security on a client connection
 */
int rxrpc_init_client_conn_security(struct rxrpc_connection *conn)
{
	const struct rxrpc_security *sec;
	struct rxrpc_key_token *token;
	struct key *key = conn->key;
	int ret;

	_enter("{%d},{%x}", conn->debug_id, key_serial(key));

	if (!key)
		return 0;

	ret = key_validate(key);
	if (ret < 0)
		return ret;

	for (token = key->payload.data[0]; token; token = token->next) {
		sec = rxrpc_security_lookup(token->security_index);
		if (sec)
			goto found;
	}
	return -EKEYREJECTED;

found:
	conn->security = sec;

	ret = conn->security->init_connection_security(conn, token);
	if (ret < 0) {
		conn->security = &rxrpc_no_security;
		return ret;
	}

	_leave(" = 0");
	return 0;
}

/*
 * Set the ops a server connection.
 */
const struct rxrpc_security *rxrpc_get_incoming_security(struct rxrpc_sock *rx,
							 struct sk_buff *skb)
{
	const struct rxrpc_security *sec;
	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);

	_enter("");

	sec = rxrpc_security_lookup(sp->hdr.securityIndex);
	if (!sec) {
		trace_rxrpc_abort(0, "SVS",
				  sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
				  RX_INVALID_OPERATION, EKEYREJECTED);
		skb->mark = RXRPC_SKB_MARK_REJECT_ABORT;
		skb->priority = RX_INVALID_OPERATION;
		return NULL;
	}

	if (sp->hdr.securityIndex != RXRPC_SECURITY_NONE &&
	    !rx->securities) {
		trace_rxrpc_abort(0, "SVR",
				  sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
				  RX_INVALID_OPERATION, EKEYREJECTED);
		skb->mark = RXRPC_SKB_MARK_REJECT_ABORT;
		skb->priority = sec->no_key_abort;
		return NULL;
	}

	return sec;
}

/*
 * Find the security key for a server connection.
 */
struct key *rxrpc_look_up_server_security(struct rxrpc_connection *conn,
					  struct sk_buff *skb,
					  u32 kvno, u32 enctype)
{
	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
	struct rxrpc_sock *rx;
	struct key *key = ERR_PTR(-EKEYREJECTED);
	key_ref_t kref = NULL;
	char kdesc[5 + 1 + 3 + 1 + 12 + 1 + 12 + 1];
	int ret;

	_enter("");

	if (enctype)
		sprintf(kdesc, "%u:%u:%u:%u",
			sp->hdr.serviceId, sp->hdr.securityIndex, kvno, enctype);
	else if (kvno)
		sprintf(kdesc, "%u:%u:%u",
			sp->hdr.serviceId, sp->hdr.securityIndex, kvno);
	else
		sprintf(kdesc, "%u:%u",
			sp->hdr.serviceId, sp->hdr.securityIndex);

	rcu_read_lock();

	rx = rcu_dereference(conn->local->service);
	if (!rx)
		goto out;

	/* look through the service's keyring */
	kref = keyring_search(make_key_ref(rx->securities, 1UL),
			      &key_type_rxrpc_s, kdesc, true);
	if (IS_ERR(kref)) {
		key = ERR_CAST(kref);
		goto out;
	}

	key = key_ref_to_ptr(kref);

	ret = key_validate(key);
	if (ret < 0) {
		key_put(key);
		key = ERR_PTR(ret);
		goto out;
	}

out:
	rcu_read_unlock();
	return key;
}