Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 10 | * Copyright (C) 2007 Hewlett-Packard Development Company, L.P. |
Paul Moore | 82c21bf | 2011-08-01 11:10:33 +0000 | [diff] [blame] | 11 | * Paul Moore <paul@paul-moore.com> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | * |
| 13 | * This program is free software; you can redistribute it and/or modify |
| 14 | * it under the terms of the GNU General Public License version 2, |
| 15 | * as published by the Free Software Foundation. |
| 16 | */ |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/types.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 19 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/stddef.h> |
| 21 | #include <linux/kernel.h> |
| 22 | #include <linux/list.h> |
| 23 | #include <linux/notifier.h> |
| 24 | #include <linux/netdevice.h> |
| 25 | #include <linux/rcupdate.h> |
Eric W. Biederman | e9dc865 | 2007-09-12 13:02:17 +0200 | [diff] [blame] | 26 | #include <net/net_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | |
| 28 | #include "security.h" |
| 29 | #include "objsec.h" |
| 30 | #include "netif.h" |
| 31 | |
| 32 | #define SEL_NETIF_HASH_SIZE 64 |
| 33 | #define SEL_NETIF_HASH_MAX 1024 |
| 34 | |
Eric Paris | 338366c | 2008-04-18 17:38:22 -0400 | [diff] [blame] | 35 | struct sel_netif { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | struct list_head list; |
| 37 | struct netif_security_struct nsec; |
| 38 | struct rcu_head rcu_head; |
| 39 | }; |
| 40 | |
| 41 | static u32 sel_netif_total; |
| 42 | static LIST_HEAD(sel_netif_list); |
| 43 | static DEFINE_SPINLOCK(sel_netif_lock); |
| 44 | static struct list_head sel_netif_hash[SEL_NETIF_HASH_SIZE]; |
| 45 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 46 | /** |
| 47 | * sel_netif_hashfn - Hashing function for the interface table |
| 48 | * @ifindex: the network interface |
| 49 | * |
| 50 | * Description: |
| 51 | * This is the hashing function for the network interface table, it returns the |
| 52 | * bucket number for the given interface. |
| 53 | * |
| 54 | */ |
| 55 | static inline u32 sel_netif_hashfn(int ifindex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | { |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 57 | return (ifindex & (SEL_NETIF_HASH_SIZE - 1)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | } |
| 59 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 60 | /** |
| 61 | * sel_netif_find - Search for an interface record |
| 62 | * @ifindex: the network interface |
| 63 | * |
| 64 | * Description: |
| 65 | * Search the network interface table and return the record matching @ifindex. |
| 66 | * If an entry can not be found in the table return NULL. |
| 67 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | */ |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 69 | static inline struct sel_netif *sel_netif_find(int ifindex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | { |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 71 | int idx = sel_netif_hashfn(ifindex); |
| 72 | struct sel_netif *netif; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 74 | list_for_each_entry_rcu(netif, &sel_netif_hash[idx], list) |
| 75 | /* all of the devices should normally fit in the hash, so we |
| 76 | * optimize for that case */ |
| 77 | if (likely(netif->nsec.ifindex == ifindex)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | return netif; |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 79 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | return NULL; |
| 81 | } |
| 82 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 83 | /** |
| 84 | * sel_netif_insert - Insert a new interface into the table |
| 85 | * @netif: the new interface record |
| 86 | * |
| 87 | * Description: |
| 88 | * Add a new interface record to the network interface hash table. Returns |
| 89 | * zero on success, negative values on failure. |
| 90 | * |
| 91 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | static int sel_netif_insert(struct sel_netif *netif) |
| 93 | { |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 94 | int idx; |
Eric Paris | 338366c | 2008-04-18 17:38:22 -0400 | [diff] [blame] | 95 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 96 | if (sel_netif_total >= SEL_NETIF_HASH_MAX) |
| 97 | return -ENOSPC; |
Eric Paris | 338366c | 2008-04-18 17:38:22 -0400 | [diff] [blame] | 98 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 99 | idx = sel_netif_hashfn(netif->nsec.ifindex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | list_add_rcu(&netif->list, &sel_netif_hash[idx]); |
| 101 | sel_netif_total++; |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 102 | |
| 103 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | } |
| 105 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 106 | /** |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 107 | * sel_netif_destroy - Remove an interface record from the table |
| 108 | * @netif: the existing interface record |
| 109 | * |
| 110 | * Description: |
| 111 | * Remove an existing interface record from the network interface table. |
| 112 | * |
| 113 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | static void sel_netif_destroy(struct sel_netif *netif) |
| 115 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | list_del_rcu(&netif->list); |
| 117 | sel_netif_total--; |
Lai Jiangshan | 690273f | 2011-03-18 12:03:19 +0800 | [diff] [blame] | 118 | kfree_rcu(netif, rcu_head); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | } |
| 120 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 121 | /** |
| 122 | * sel_netif_sid_slow - Lookup the SID of a network interface using the policy |
| 123 | * @ifindex: the network interface |
| 124 | * @sid: interface SID |
| 125 | * |
| 126 | * Description: |
| 127 | * This function determines the SID of a network interface by quering the |
| 128 | * security policy. The result is added to the network interface table to |
| 129 | * speedup future queries. Returns zero on success, negative values on |
| 130 | * failure. |
| 131 | * |
| 132 | */ |
| 133 | static int sel_netif_sid_slow(int ifindex, u32 *sid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | { |
| 135 | int ret; |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 136 | struct sel_netif *netif; |
| 137 | struct sel_netif *new = NULL; |
| 138 | struct net_device *dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 140 | /* NOTE: we always use init's network namespace since we don't |
| 141 | * currently support containers */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 143 | dev = dev_get_by_index(&init_net, ifindex); |
Paul Moore | 71f1cb0 | 2008-01-29 08:51:16 -0500 | [diff] [blame] | 144 | if (unlikely(dev == NULL)) { |
| 145 | printk(KERN_WARNING |
| 146 | "SELinux: failure in sel_netif_sid_slow()," |
| 147 | " invalid network interface (%d)\n", ifindex); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 148 | return -ENOENT; |
Paul Moore | 71f1cb0 | 2008-01-29 08:51:16 -0500 | [diff] [blame] | 149 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | spin_lock_bh(&sel_netif_lock); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 152 | netif = sel_netif_find(ifindex); |
| 153 | if (netif != NULL) { |
| 154 | *sid = netif->nsec.sid; |
| 155 | ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | goto out; |
| 157 | } |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 158 | new = kzalloc(sizeof(*new), GFP_ATOMIC); |
| 159 | if (new == NULL) { |
| 160 | ret = -ENOMEM; |
| 161 | goto out; |
| 162 | } |
| 163 | ret = security_netif_sid(dev->name, &new->nsec.sid); |
| 164 | if (ret != 0) |
| 165 | goto out; |
| 166 | new->nsec.ifindex = ifindex; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | ret = sel_netif_insert(new); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 168 | if (ret != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | goto out; |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 170 | *sid = new->nsec.sid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | out: |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 173 | spin_unlock_bh(&sel_netif_lock); |
| 174 | dev_put(dev); |
Paul Moore | 71f1cb0 | 2008-01-29 08:51:16 -0500 | [diff] [blame] | 175 | if (unlikely(ret)) { |
| 176 | printk(KERN_WARNING |
| 177 | "SELinux: failure in sel_netif_sid_slow()," |
| 178 | " unable to determine network interface label (%d)\n", |
| 179 | ifindex); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 180 | kfree(new); |
Paul Moore | 71f1cb0 | 2008-01-29 08:51:16 -0500 | [diff] [blame] | 181 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | return ret; |
| 183 | } |
| 184 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 185 | /** |
| 186 | * sel_netif_sid - Lookup the SID of a network interface |
| 187 | * @ifindex: the network interface |
| 188 | * @sid: interface SID |
| 189 | * |
| 190 | * Description: |
| 191 | * This function determines the SID of a network interface using the fastest |
| 192 | * method possible. First the interface table is queried, but if an entry |
| 193 | * can't be found then the policy is queried and the result is added to the |
| 194 | * table to speedup future queries. Returns zero on success, negative values |
| 195 | * on failure. |
| 196 | * |
| 197 | */ |
| 198 | int sel_netif_sid(int ifindex, u32 *sid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | struct sel_netif *netif; |
| 201 | |
| 202 | rcu_read_lock(); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 203 | netif = sel_netif_find(ifindex); |
| 204 | if (likely(netif != NULL)) { |
| 205 | *sid = netif->nsec.sid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | rcu_read_unlock(); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 207 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | rcu_read_unlock(); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 210 | |
| 211 | return sel_netif_sid_slow(ifindex, sid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | } |
| 213 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 214 | /** |
| 215 | * sel_netif_kill - Remove an entry from the network interface table |
| 216 | * @ifindex: the network interface |
| 217 | * |
| 218 | * Description: |
| 219 | * This function removes the entry matching @ifindex from the network interface |
| 220 | * table if it exists. |
| 221 | * |
| 222 | */ |
| 223 | static void sel_netif_kill(int ifindex) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | { |
| 225 | struct sel_netif *netif; |
| 226 | |
Paul E. McKenney | 6184425 | 2008-04-21 18:12:33 -0700 | [diff] [blame] | 227 | rcu_read_lock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | spin_lock_bh(&sel_netif_lock); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 229 | netif = sel_netif_find(ifindex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | if (netif) |
| 231 | sel_netif_destroy(netif); |
| 232 | spin_unlock_bh(&sel_netif_lock); |
Paul E. McKenney | 6184425 | 2008-04-21 18:12:33 -0700 | [diff] [blame] | 233 | rcu_read_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | } |
| 235 | |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 236 | /** |
| 237 | * sel_netif_flush - Flush the entire network interface table |
| 238 | * |
| 239 | * Description: |
| 240 | * Remove all entries from the network interface table. |
| 241 | * |
| 242 | */ |
Paul Moore | 615e51f | 2014-06-26 14:33:56 -0400 | [diff] [blame] | 243 | void sel_netif_flush(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | { |
| 245 | int idx; |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 246 | struct sel_netif *netif; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 247 | |
| 248 | spin_lock_bh(&sel_netif_lock); |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 249 | for (idx = 0; idx < SEL_NETIF_HASH_SIZE; idx++) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | list_for_each_entry(netif, &sel_netif_hash[idx], list) |
| 251 | sel_netif_destroy(netif); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | spin_unlock_bh(&sel_netif_lock); |
| 253 | } |
| 254 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | static int sel_netif_netdev_notifier_handler(struct notifier_block *this, |
Eric Paris | 338366c | 2008-04-18 17:38:22 -0400 | [diff] [blame] | 256 | unsigned long event, void *ptr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | { |
Jiri Pirko | 351638e | 2013-05-28 01:30:21 +0000 | [diff] [blame] | 258 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | |
YOSHIFUJI Hideaki | c346dca | 2008-03-25 21:47:49 +0900 | [diff] [blame] | 260 | if (dev_net(dev) != &init_net) |
Eric W. Biederman | e9dc865 | 2007-09-12 13:02:17 +0200 | [diff] [blame] | 261 | return NOTIFY_DONE; |
| 262 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | if (event == NETDEV_DOWN) |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 264 | sel_netif_kill(dev->ifindex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 265 | |
| 266 | return NOTIFY_DONE; |
| 267 | } |
| 268 | |
| 269 | static struct notifier_block sel_netif_netdev_notifier = { |
| 270 | .notifier_call = sel_netif_netdev_notifier_handler, |
| 271 | }; |
| 272 | |
| 273 | static __init int sel_netif_init(void) |
| 274 | { |
Paul Moore | 942ba36 | 2014-08-07 20:55:30 -0400 | [diff] [blame] | 275 | int i; |
Eric Paris | 338366c | 2008-04-18 17:38:22 -0400 | [diff] [blame] | 276 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | if (!selinux_enabled) |
Paul Moore | e8bfdb9 | 2008-01-29 08:38:08 -0500 | [diff] [blame] | 278 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | |
| 280 | for (i = 0; i < SEL_NETIF_HASH_SIZE; i++) |
| 281 | INIT_LIST_HEAD(&sel_netif_hash[i]); |
| 282 | |
| 283 | register_netdevice_notifier(&sel_netif_netdev_notifier); |
Eric Paris | 338366c | 2008-04-18 17:38:22 -0400 | [diff] [blame] | 284 | |
Paul Moore | 942ba36 | 2014-08-07 20:55:30 -0400 | [diff] [blame] | 285 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | } |
| 287 | |
| 288 | __initcall(sel_netif_init); |
| 289 | |