diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /security/selinux/netif.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'security/selinux/netif.c')
-rw-r--r-- | security/selinux/netif.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/security/selinux/netif.c b/security/selinux/netif.c new file mode 100644 index 00000000000..718d7be9f4d --- /dev/null +++ b/security/selinux/netif.c | |||
@@ -0,0 +1,270 @@ | |||
1 | /* | ||
2 | * Network interface table. | ||
3 | * | ||
4 | * Network interfaces (devices) do not have a security field, so we | ||
5 | * maintain a table associating each interface with a SID. | ||
6 | * | ||
7 | * Author: James Morris <jmorris@redhat.com> | ||
8 | * | ||
9 | * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or modify | ||
12 | * it under the terms of the GNU General Public License version 2, | ||
13 | * as published by the Free Software Foundation. | ||
14 | */ | ||
15 | #include <linux/init.h> | ||
16 | #include <linux/types.h> | ||
17 | #include <linux/stddef.h> | ||
18 | #include <linux/kernel.h> | ||
19 | #include <linux/list.h> | ||
20 | #include <linux/notifier.h> | ||
21 | #include <linux/netdevice.h> | ||
22 | #include <linux/rcupdate.h> | ||
23 | |||
24 | #include "security.h" | ||
25 | #include "objsec.h" | ||
26 | #include "netif.h" | ||
27 | |||
28 | #define SEL_NETIF_HASH_SIZE 64 | ||
29 | #define SEL_NETIF_HASH_MAX 1024 | ||
30 | |||
31 | #undef DEBUG | ||
32 | |||
33 | #ifdef DEBUG | ||
34 | #define DEBUGP printk | ||
35 | #else | ||
36 | #define DEBUGP(format, args...) | ||
37 | #endif | ||
38 | |||
39 | struct sel_netif | ||
40 | { | ||
41 | struct list_head list; | ||
42 | struct netif_security_struct nsec; | ||
43 | struct rcu_head rcu_head; | ||
44 | }; | ||
45 | |||
46 | static u32 sel_netif_total; | ||
47 | static LIST_HEAD(sel_netif_list); | ||
48 | static DEFINE_SPINLOCK(sel_netif_lock); | ||
49 | static struct list_head sel_netif_hash[SEL_NETIF_HASH_SIZE]; | ||
50 | |||
51 | static inline u32 sel_netif_hasfn(struct net_device *dev) | ||
52 | { | ||
53 | return (dev->ifindex & (SEL_NETIF_HASH_SIZE - 1)); | ||
54 | } | ||
55 | |||
56 | /* | ||
57 | * All of the devices should normally fit in the hash, so we optimize | ||
58 | * for that case. | ||
59 | */ | ||
60 | static inline struct sel_netif *sel_netif_find(struct net_device *dev) | ||
61 | { | ||
62 | struct list_head *pos; | ||
63 | int idx = sel_netif_hasfn(dev); | ||
64 | |||
65 | __list_for_each_rcu(pos, &sel_netif_hash[idx]) { | ||
66 | struct sel_netif *netif = list_entry(pos, | ||
67 | struct sel_netif, list); | ||
68 | if (likely(netif->nsec.dev == dev)) | ||
69 | return netif; | ||
70 | } | ||
71 | return NULL; | ||
72 | } | ||
73 | |||
74 | static int sel_netif_insert(struct sel_netif *netif) | ||
75 | { | ||
76 | int idx, ret = 0; | ||
77 | |||
78 | if (sel_netif_total >= SEL_NETIF_HASH_MAX) { | ||
79 | ret = -ENOSPC; | ||
80 | goto out; | ||
81 | } | ||
82 | |||
83 | idx = sel_netif_hasfn(netif->nsec.dev); | ||
84 | list_add_rcu(&netif->list, &sel_netif_hash[idx]); | ||
85 | sel_netif_total++; | ||
86 | out: | ||
87 | return ret; | ||
88 | } | ||
89 | |||
90 | static void sel_netif_free(struct rcu_head *p) | ||
91 | { | ||
92 | struct sel_netif *netif = container_of(p, struct sel_netif, rcu_head); | ||
93 | |||
94 | DEBUGP("%s: %s\n", __FUNCTION__, netif->nsec.dev->name); | ||
95 | kfree(netif); | ||
96 | } | ||
97 | |||
98 | static void sel_netif_destroy(struct sel_netif *netif) | ||
99 | { | ||
100 | DEBUGP("%s: %s\n", __FUNCTION__, netif->nsec.dev->name); | ||
101 | |||
102 | list_del_rcu(&netif->list); | ||
103 | sel_netif_total--; | ||
104 | call_rcu(&netif->rcu_head, sel_netif_free); | ||
105 | } | ||
106 | |||
107 | static struct sel_netif *sel_netif_lookup(struct net_device *dev) | ||
108 | { | ||
109 | int ret; | ||
110 | struct sel_netif *netif, *new; | ||
111 | struct netif_security_struct *nsec; | ||
112 | |||
113 | netif = sel_netif_find(dev); | ||
114 | if (likely(netif != NULL)) | ||
115 | goto out; | ||
116 | |||
117 | new = kmalloc(sizeof(*new), GFP_ATOMIC); | ||
118 | if (!new) { | ||
119 | netif = ERR_PTR(-ENOMEM); | ||
120 | goto out; | ||
121 | } | ||
122 | |||
123 | memset(new, 0, sizeof(*new)); | ||
124 | nsec = &new->nsec; | ||
125 | |||
126 | ret = security_netif_sid(dev->name, &nsec->if_sid, &nsec->msg_sid); | ||
127 | if (ret < 0) { | ||
128 | kfree(new); | ||
129 | netif = ERR_PTR(ret); | ||
130 | goto out; | ||
131 | } | ||
132 | |||
133 | nsec->dev = dev; | ||
134 | |||
135 | spin_lock_bh(&sel_netif_lock); | ||
136 | |||
137 | netif = sel_netif_find(dev); | ||
138 | if (netif) { | ||
139 | spin_unlock_bh(&sel_netif_lock); | ||
140 | kfree(new); | ||
141 | goto out; | ||
142 | } | ||
143 | |||
144 | ret = sel_netif_insert(new); | ||
145 | spin_unlock_bh(&sel_netif_lock); | ||
146 | |||
147 | if (ret) { | ||
148 | kfree(new); | ||
149 | netif = ERR_PTR(ret); | ||
150 | goto out; | ||
151 | } | ||
152 | |||
153 | netif = new; | ||
154 | |||
155 | DEBUGP("new: ifindex=%u name=%s if_sid=%u msg_sid=%u\n", dev->ifindex, dev->name, | ||
156 | nsec->if_sid, nsec->msg_sid); | ||
157 | out: | ||
158 | return netif; | ||
159 | } | ||
160 | |||
161 | static void sel_netif_assign_sids(u32 if_sid_in, u32 msg_sid_in, u32 *if_sid_out, u32 *msg_sid_out) | ||
162 | { | ||
163 | if (if_sid_out) | ||
164 | *if_sid_out = if_sid_in; | ||
165 | if (msg_sid_out) | ||
166 | *msg_sid_out = msg_sid_in; | ||
167 | } | ||
168 | |||
169 | static int sel_netif_sids_slow(struct net_device *dev, u32 *if_sid, u32 *msg_sid) | ||
170 | { | ||
171 | int ret = 0; | ||
172 | u32 tmp_if_sid, tmp_msg_sid; | ||
173 | |||
174 | ret = security_netif_sid(dev->name, &tmp_if_sid, &tmp_msg_sid); | ||
175 | if (!ret) | ||
176 | sel_netif_assign_sids(tmp_if_sid, tmp_msg_sid, if_sid, msg_sid); | ||
177 | return ret; | ||
178 | } | ||
179 | |||
180 | int sel_netif_sids(struct net_device *dev, u32 *if_sid, u32 *msg_sid) | ||
181 | { | ||
182 | int ret = 0; | ||
183 | struct sel_netif *netif; | ||
184 | |||
185 | rcu_read_lock(); | ||
186 | netif = sel_netif_lookup(dev); | ||
187 | if (IS_ERR(netif)) { | ||
188 | rcu_read_unlock(); | ||
189 | ret = sel_netif_sids_slow(dev, if_sid, msg_sid); | ||
190 | goto out; | ||
191 | } | ||
192 | sel_netif_assign_sids(netif->nsec.if_sid, netif->nsec.msg_sid, if_sid, msg_sid); | ||
193 | rcu_read_unlock(); | ||
194 | out: | ||
195 | return ret; | ||
196 | } | ||
197 | |||
198 | static void sel_netif_kill(struct net_device *dev) | ||
199 | { | ||
200 | struct sel_netif *netif; | ||
201 | |||
202 | spin_lock_bh(&sel_netif_lock); | ||
203 | netif = sel_netif_find(dev); | ||
204 | if (netif) | ||
205 | sel_netif_destroy(netif); | ||
206 | spin_unlock_bh(&sel_netif_lock); | ||
207 | } | ||
208 | |||
209 | static void sel_netif_flush(void) | ||
210 | { | ||
211 | int idx; | ||
212 | |||
213 | spin_lock_bh(&sel_netif_lock); | ||
214 | for (idx = 0; idx < SEL_NETIF_HASH_SIZE; idx++) { | ||
215 | struct sel_netif *netif; | ||
216 | |||
217 | list_for_each_entry(netif, &sel_netif_hash[idx], list) | ||
218 | sel_netif_destroy(netif); | ||
219 | } | ||
220 | spin_unlock_bh(&sel_netif_lock); | ||
221 | } | ||
222 | |||
223 | static int sel_netif_avc_callback(u32 event, u32 ssid, u32 tsid, | ||
224 | u16 class, u32 perms, u32 *retained) | ||
225 | { | ||
226 | if (event == AVC_CALLBACK_RESET) { | ||
227 | sel_netif_flush(); | ||
228 | synchronize_net(); | ||
229 | } | ||
230 | return 0; | ||
231 | } | ||
232 | |||
233 | static int sel_netif_netdev_notifier_handler(struct notifier_block *this, | ||
234 | unsigned long event, void *ptr) | ||
235 | { | ||
236 | struct net_device *dev = ptr; | ||
237 | |||
238 | if (event == NETDEV_DOWN) | ||
239 | sel_netif_kill(dev); | ||
240 | |||
241 | return NOTIFY_DONE; | ||
242 | } | ||
243 | |||
244 | static struct notifier_block sel_netif_netdev_notifier = { | ||
245 | .notifier_call = sel_netif_netdev_notifier_handler, | ||
246 | }; | ||
247 | |||
248 | static __init int sel_netif_init(void) | ||
249 | { | ||
250 | int i, err = 0; | ||
251 | |||
252 | if (!selinux_enabled) | ||
253 | goto out; | ||
254 | |||
255 | for (i = 0; i < SEL_NETIF_HASH_SIZE; i++) | ||
256 | INIT_LIST_HEAD(&sel_netif_hash[i]); | ||
257 | |||
258 | register_netdevice_notifier(&sel_netif_netdev_notifier); | ||
259 | |||
260 | err = avc_add_callback(sel_netif_avc_callback, AVC_CALLBACK_RESET, | ||
261 | SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0); | ||
262 | if (err) | ||
263 | panic("avc_add_callback() failed, error %d\n", err); | ||
264 | |||
265 | out: | ||
266 | return err; | ||
267 | } | ||
268 | |||
269 | __initcall(sel_netif_init); | ||
270 | |||