blob: 60d1d364430af6497c681c25647ffb09bdcaa009 [file] [log] [blame]
David Howells17926a72007-04-26 15:48:28 -07001/* RxRPC security handling
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
12#include <linux/module.h>
13#include <linux/net.h>
14#include <linux/skbuff.h>
15#include <linux/udp.h>
16#include <linux/crypto.h>
17#include <net/sock.h>
18#include <net/af_rxrpc.h>
19#include "ar-internal.h"
20
21static LIST_HEAD(rxrpc_security_methods);
22static DECLARE_RWSEM(rxrpc_security_sem);
23
24/*
25 * get an RxRPC security module
26 */
27static struct rxrpc_security *rxrpc_security_get(struct rxrpc_security *sec)
28{
29 return try_module_get(sec->owner) ? sec : NULL;
30}
31
32/*
33 * release an RxRPC security module
34 */
35static void rxrpc_security_put(struct rxrpc_security *sec)
36{
37 module_put(sec->owner);
38}
39
40/*
41 * look up an rxrpc security module
42 */
43struct rxrpc_security *rxrpc_security_lookup(u8 security_index)
44{
45 struct rxrpc_security *sec = NULL;
46
47 _enter("");
48
49 down_read(&rxrpc_security_sem);
50
51 list_for_each_entry(sec, &rxrpc_security_methods, link) {
52 if (sec->security_index == security_index) {
53 if (unlikely(!rxrpc_security_get(sec)))
54 break;
55 goto out;
56 }
57 }
58
59 sec = NULL;
60out:
61 up_read(&rxrpc_security_sem);
62 _leave(" = %p [%s]", sec, sec ? sec->name : "");
63 return sec;
64}
65
66/**
67 * rxrpc_register_security - register an RxRPC security handler
68 * @sec: security module
69 *
70 * register an RxRPC security handler for use by RxRPC
71 */
72int rxrpc_register_security(struct rxrpc_security *sec)
73{
74 struct rxrpc_security *psec;
75 int ret;
76
77 _enter("");
78 down_write(&rxrpc_security_sem);
79
80 ret = -EEXIST;
81 list_for_each_entry(psec, &rxrpc_security_methods, link) {
82 if (psec->security_index == sec->security_index)
83 goto out;
84 }
85
86 list_add(&sec->link, &rxrpc_security_methods);
87
88 printk(KERN_NOTICE "RxRPC: Registered security type %d '%s'\n",
89 sec->security_index, sec->name);
90 ret = 0;
91
92out:
93 up_write(&rxrpc_security_sem);
94 _leave(" = %d", ret);
95 return ret;
96}
97
98EXPORT_SYMBOL_GPL(rxrpc_register_security);
99
100/**
101 * rxrpc_unregister_security - unregister an RxRPC security handler
102 * @sec: security module
103 *
104 * unregister an RxRPC security handler
105 */
106void rxrpc_unregister_security(struct rxrpc_security *sec)
107{
108
109 _enter("");
110 down_write(&rxrpc_security_sem);
111 list_del_init(&sec->link);
112 up_write(&rxrpc_security_sem);
113
114 printk(KERN_NOTICE "RxRPC: Unregistered security type %d '%s'\n",
115 sec->security_index, sec->name);
116}
117
118EXPORT_SYMBOL_GPL(rxrpc_unregister_security);
119
120/*
121 * initialise the security on a client connection
122 */
123int rxrpc_init_client_conn_security(struct rxrpc_connection *conn)
124{
125 struct rxrpc_security *sec;
126 struct key *key = conn->key;
127 int ret;
128
129 _enter("{%d},{%x}", conn->debug_id, key_serial(key));
130
131 if (!key)
132 return 0;
133
134 ret = key_validate(key);
135 if (ret < 0)
136 return ret;
137
138 sec = rxrpc_security_lookup(key->type_data.x[0]);
139 if (!sec)
140 return -EKEYREJECTED;
141 conn->security = sec;
142
143 ret = conn->security->init_connection_security(conn);
144 if (ret < 0) {
145 rxrpc_security_put(conn->security);
146 conn->security = NULL;
147 return ret;
148 }
149
150 _leave(" = 0");
151 return 0;
152}
153
154/*
155 * initialise the security on a server connection
156 */
157int rxrpc_init_server_conn_security(struct rxrpc_connection *conn)
158{
159 struct rxrpc_security *sec;
160 struct rxrpc_local *local = conn->trans->local;
161 struct rxrpc_sock *rx;
162 struct key *key;
163 key_ref_t kref;
164 char kdesc[5+1+3+1];
165
166 _enter("");
167
168 sprintf(kdesc, "%u:%u", ntohs(conn->service_id), conn->security_ix);
169
170 sec = rxrpc_security_lookup(conn->security_ix);
171 if (!sec) {
172 _leave(" = -ENOKEY [lookup]");
173 return -ENOKEY;
174 }
175
176 /* find the service */
177 read_lock_bh(&local->services_lock);
178 list_for_each_entry(rx, &local->services, listen_link) {
179 if (rx->service_id == conn->service_id)
180 goto found_service;
181 }
182
183 /* the service appears to have died */
184 read_unlock_bh(&local->services_lock);
185 rxrpc_security_put(sec);
186 _leave(" = -ENOENT");
187 return -ENOENT;
188
189found_service:
190 if (!rx->securities) {
191 read_unlock_bh(&local->services_lock);
192 rxrpc_security_put(sec);
193 _leave(" = -ENOKEY");
194 return -ENOKEY;
195 }
196
197 /* look through the service's keyring */
198 kref = keyring_search(make_key_ref(rx->securities, 1UL),
199 &key_type_rxrpc_s, kdesc);
200 if (IS_ERR(kref)) {
201 read_unlock_bh(&local->services_lock);
202 rxrpc_security_put(sec);
203 _leave(" = %ld [search]", PTR_ERR(kref));
204 return PTR_ERR(kref);
205 }
206
207 key = key_ref_to_ptr(kref);
208 read_unlock_bh(&local->services_lock);
209
210 conn->server_key = key;
211 conn->security = sec;
212
213 _leave(" = 0");
214 return 0;
215}
216
217/*
218 * secure a packet prior to transmission
219 */
220int rxrpc_secure_packet(const struct rxrpc_call *call,
221 struct sk_buff *skb,
222 size_t data_size,
223 void *sechdr)
224{
225 if (call->conn->security)
226 return call->conn->security->secure_packet(
227 call, skb, data_size, sechdr);
228 return 0;
229}
230
231/*
232 * secure a packet prior to transmission
233 */
234int rxrpc_verify_packet(const struct rxrpc_call *call, struct sk_buff *skb,
235 u32 *_abort_code)
236{
237 if (call->conn->security)
238 return call->conn->security->verify_packet(
239 call, skb, _abort_code);
240 return 0;
241}
242
243/*
244 * clear connection security
245 */
246void rxrpc_clear_conn_security(struct rxrpc_connection *conn)
247{
248 _enter("{%d}", conn->debug_id);
249
250 if (conn->security) {
251 conn->security->clear(conn);
252 rxrpc_security_put(conn->security);
253 conn->security = NULL;
254 }
255
256 key_put(conn->key);
257 key_put(conn->server_key);
258}