YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 1 | /* netfilter.c: look after the filters for various protocols. |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 2 | * Heavily influenced by the old firewall.c by David Bonn and Alan Cox. |
| 3 | * |
| 4 | * Thanks to Rob `CmdrTaco' Malda for not influencing this code in any |
| 5 | * way. |
| 6 | * |
| 7 | * Rusty Russell (C)2000 -- This code is GPL. |
Patrick McHardy | f229f6c | 2013-04-06 15:24:29 +0200 | [diff] [blame] | 8 | * Patrick McHardy (c) 2006-2012 |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 9 | */ |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 10 | #include <linux/kernel.h> |
| 11 | #include <linux/netfilter.h> |
| 12 | #include <net/protocol.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/skbuff.h> |
| 15 | #include <linux/wait.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/interrupt.h> |
| 18 | #include <linux/if.h> |
| 19 | #include <linux/netdevice.h> |
Florian Westphal | 5676864 | 2014-11-13 10:04:16 +0100 | [diff] [blame] | 20 | #include <linux/netfilter_ipv6.h> |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 21 | #include <linux/inetdevice.h> |
| 22 | #include <linux/proc_fs.h> |
Patrick McHardy | d486dd1 | 2007-02-12 11:09:55 -0800 | [diff] [blame] | 23 | #include <linux/mutex.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 24 | #include <linux/slab.h> |
Eric W. Biederman | 457c4cb | 2007-09-12 12:01:34 +0200 | [diff] [blame] | 25 | #include <net/net_namespace.h> |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 26 | #include <net/sock.h> |
| 27 | |
| 28 | #include "nf_internals.h" |
| 29 | |
Patrick McHardy | d486dd1 | 2007-02-12 11:09:55 -0800 | [diff] [blame] | 30 | static DEFINE_MUTEX(afinfo_mutex); |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 31 | |
Arnd Bergmann | 0906a37 | 2010-03-09 20:59:15 +0100 | [diff] [blame] | 32 | const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO] __read_mostly; |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 33 | EXPORT_SYMBOL(nf_afinfo); |
Florian Westphal | 2a7851b | 2013-05-17 03:56:10 +0000 | [diff] [blame] | 34 | const struct nf_ipv6_ops __rcu *nf_ipv6_ops __read_mostly; |
| 35 | EXPORT_SYMBOL_GPL(nf_ipv6_ops); |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 36 | |
Florian Westphal | e7c8899 | 2015-07-14 17:51:07 +0200 | [diff] [blame] | 37 | DEFINE_PER_CPU(bool, nf_skb_duplicated); |
| 38 | EXPORT_SYMBOL_GPL(nf_skb_duplicated); |
| 39 | |
Patrick McHardy | 1e796fd | 2007-12-17 22:42:27 -0800 | [diff] [blame] | 40 | int nf_register_afinfo(const struct nf_afinfo *afinfo) |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 41 | { |
Pablo Neira Ayuso | 7926dbf | 2014-07-31 20:38:46 +0200 | [diff] [blame] | 42 | mutex_lock(&afinfo_mutex); |
Stephen Hemminger | a9b3cd7 | 2011-08-01 16:19:00 +0000 | [diff] [blame] | 43 | RCU_INIT_POINTER(nf_afinfo[afinfo->family], afinfo); |
Patrick McHardy | d486dd1 | 2007-02-12 11:09:55 -0800 | [diff] [blame] | 44 | mutex_unlock(&afinfo_mutex); |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 45 | return 0; |
| 46 | } |
| 47 | EXPORT_SYMBOL_GPL(nf_register_afinfo); |
| 48 | |
Patrick McHardy | 1e796fd | 2007-12-17 22:42:27 -0800 | [diff] [blame] | 49 | void nf_unregister_afinfo(const struct nf_afinfo *afinfo) |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 50 | { |
Patrick McHardy | d486dd1 | 2007-02-12 11:09:55 -0800 | [diff] [blame] | 51 | mutex_lock(&afinfo_mutex); |
Stephen Hemminger | a9b3cd7 | 2011-08-01 16:19:00 +0000 | [diff] [blame] | 52 | RCU_INIT_POINTER(nf_afinfo[afinfo->family], NULL); |
Patrick McHardy | d486dd1 | 2007-02-12 11:09:55 -0800 | [diff] [blame] | 53 | mutex_unlock(&afinfo_mutex); |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 54 | synchronize_rcu(); |
| 55 | } |
| 56 | EXPORT_SYMBOL_GPL(nf_unregister_afinfo); |
| 57 | |
Zhouyi Zhou | d1c85c2 | 2014-08-22 10:40:15 +0800 | [diff] [blame] | 58 | #ifdef HAVE_JUMP_LABEL |
Ingo Molnar | c5905af | 2012-02-24 08:31:31 +0100 | [diff] [blame] | 59 | struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; |
Eric Dumazet | a2d7ec5 | 2011-11-18 17:32:46 +0000 | [diff] [blame] | 60 | EXPORT_SYMBOL(nf_hooks_needed); |
| 61 | #endif |
| 62 | |
Patrick McHardy | fd706d6 | 2007-02-12 11:10:14 -0800 | [diff] [blame] | 63 | static DEFINE_MUTEX(nf_hook_mutex); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 64 | |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 65 | static struct list_head *nf_find_hook_list(struct net *net, |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 66 | const struct nf_hook_ops *reg) |
Eric W. Biederman | 0edcf28 | 2015-07-10 18:14:30 -0500 | [diff] [blame] | 67 | { |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 68 | struct list_head *hook_list = NULL; |
Eric W. Biederman | 0edcf28 | 2015-07-10 18:14:30 -0500 | [diff] [blame] | 69 | |
| 70 | if (reg->pf != NFPROTO_NETDEV) |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 71 | hook_list = &net->nf.hooks[reg->pf][reg->hooknum]; |
Eric W. Biederman | 0edcf28 | 2015-07-10 18:14:30 -0500 | [diff] [blame] | 72 | else if (reg->hooknum == NF_NETDEV_INGRESS) { |
| 73 | #ifdef CONFIG_NETFILTER_INGRESS |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 74 | if (reg->dev && dev_net(reg->dev) == net) |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 75 | hook_list = ®->dev->nf_hooks_ingress; |
Eric W. Biederman | 0edcf28 | 2015-07-10 18:14:30 -0500 | [diff] [blame] | 76 | #endif |
| 77 | } |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 78 | return hook_list; |
Eric W. Biederman | 0edcf28 | 2015-07-10 18:14:30 -0500 | [diff] [blame] | 79 | } |
| 80 | |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 81 | struct nf_hook_entry { |
| 82 | const struct nf_hook_ops *orig_ops; |
| 83 | struct nf_hook_ops ops; |
| 84 | }; |
| 85 | |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 86 | int nf_register_net_hook(struct net *net, const struct nf_hook_ops *reg) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 87 | { |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 88 | struct list_head *hook_list; |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 89 | struct nf_hook_entry *entry; |
| 90 | struct nf_hook_ops *elem; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 91 | |
Aaron Conole | d4bb5ca | 2016-09-21 11:35:05 -0400 | [diff] [blame^] | 92 | if (reg->pf == NFPROTO_NETDEV && |
| 93 | (reg->hooknum != NF_NETDEV_INGRESS || |
| 94 | !reg->dev || dev_net(reg->dev) != net)) |
| 95 | return -EINVAL; |
| 96 | |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 97 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); |
| 98 | if (!entry) |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 99 | return -ENOMEM; |
| 100 | |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 101 | entry->orig_ops = reg; |
| 102 | entry->ops = *reg; |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 103 | |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 104 | hook_list = nf_find_hook_list(net, reg); |
| 105 | if (!hook_list) { |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 106 | kfree(entry); |
Eric W. Biederman | 0edcf28 | 2015-07-10 18:14:30 -0500 | [diff] [blame] | 107 | return -ENOENT; |
Eric W. Biederman | e317fa5 | 2015-07-18 10:21:14 -0500 | [diff] [blame] | 108 | } |
Pablo Neira | e687ad6 | 2015-05-13 18:19:38 +0200 | [diff] [blame] | 109 | |
Eric W. Biederman | 0edcf28 | 2015-07-10 18:14:30 -0500 | [diff] [blame] | 110 | mutex_lock(&nf_hook_mutex); |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 111 | list_for_each_entry(elem, hook_list, list) { |
Li Zefan | 4c61097 | 2007-12-04 23:22:26 -0800 | [diff] [blame] | 112 | if (reg->priority < elem->priority) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 113 | break; |
| 114 | } |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 115 | list_add_rcu(&entry->ops.list, elem->list.prev); |
Patrick McHardy | fd706d6 | 2007-02-12 11:10:14 -0800 | [diff] [blame] | 116 | mutex_unlock(&nf_hook_mutex); |
Eric W. Biederman | 4c09115 | 2015-07-10 18:13:58 -0500 | [diff] [blame] | 117 | #ifdef CONFIG_NETFILTER_INGRESS |
| 118 | if (reg->pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_INGRESS) |
| 119 | net_inc_ingress_queue(); |
| 120 | #endif |
Zhouyi Zhou | d1c85c2 | 2014-08-22 10:40:15 +0800 | [diff] [blame] | 121 | #ifdef HAVE_JUMP_LABEL |
Ingo Molnar | c5905af | 2012-02-24 08:31:31 +0100 | [diff] [blame] | 122 | static_key_slow_inc(&nf_hooks_needed[reg->pf][reg->hooknum]); |
Eric Dumazet | a2d7ec5 | 2011-11-18 17:32:46 +0000 | [diff] [blame] | 123 | #endif |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 124 | return 0; |
| 125 | } |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 126 | EXPORT_SYMBOL(nf_register_net_hook); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 127 | |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 128 | void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *reg) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 129 | { |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 130 | struct list_head *hook_list; |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 131 | struct nf_hook_entry *entry; |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 132 | struct nf_hook_ops *elem; |
| 133 | |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 134 | hook_list = nf_find_hook_list(net, reg); |
| 135 | if (!hook_list) |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 136 | return; |
| 137 | |
Patrick McHardy | fd706d6 | 2007-02-12 11:10:14 -0800 | [diff] [blame] | 138 | mutex_lock(&nf_hook_mutex); |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 139 | list_for_each_entry(elem, hook_list, list) { |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 140 | entry = container_of(elem, struct nf_hook_entry, ops); |
| 141 | if (entry->orig_ops == reg) { |
| 142 | list_del_rcu(&entry->ops.list); |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 143 | break; |
| 144 | } |
| 145 | } |
Patrick McHardy | fd706d6 | 2007-02-12 11:10:14 -0800 | [diff] [blame] | 146 | mutex_unlock(&nf_hook_mutex); |
Pablo Neira Ayuso | 3bbd14e | 2015-07-20 13:32:52 +0200 | [diff] [blame] | 147 | if (&elem->list == hook_list) { |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 148 | WARN(1, "nf_unregister_net_hook: hook not found!\n"); |
| 149 | return; |
| 150 | } |
Pablo Neira | e687ad6 | 2015-05-13 18:19:38 +0200 | [diff] [blame] | 151 | #ifdef CONFIG_NETFILTER_INGRESS |
Eric W. Biederman | 4c09115 | 2015-07-10 18:13:58 -0500 | [diff] [blame] | 152 | if (reg->pf == NFPROTO_NETDEV && reg->hooknum == NF_NETDEV_INGRESS) |
| 153 | net_dec_ingress_queue(); |
Pablo Neira | e687ad6 | 2015-05-13 18:19:38 +0200 | [diff] [blame] | 154 | #endif |
Zhouyi Zhou | d1c85c2 | 2014-08-22 10:40:15 +0800 | [diff] [blame] | 155 | #ifdef HAVE_JUMP_LABEL |
Ingo Molnar | c5905af | 2012-02-24 08:31:31 +0100 | [diff] [blame] | 156 | static_key_slow_dec(&nf_hooks_needed[reg->pf][reg->hooknum]); |
Eric Dumazet | a2d7ec5 | 2011-11-18 17:32:46 +0000 | [diff] [blame] | 157 | #endif |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 158 | synchronize_net(); |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 159 | nf_queue_nf_hook_drop(net, &entry->ops); |
Florian Westphal | 514ed62 | 2015-10-08 23:38:07 +0200 | [diff] [blame] | 160 | /* other cpu might still process nfqueue verdict that used reg */ |
| 161 | synchronize_net(); |
Pablo Neira Ayuso | 7181eba | 2015-07-20 09:31:25 +0200 | [diff] [blame] | 162 | kfree(entry); |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 163 | } |
| 164 | EXPORT_SYMBOL(nf_unregister_net_hook); |
| 165 | |
| 166 | int nf_register_net_hooks(struct net *net, const struct nf_hook_ops *reg, |
| 167 | unsigned int n) |
| 168 | { |
| 169 | unsigned int i; |
| 170 | int err = 0; |
| 171 | |
| 172 | for (i = 0; i < n; i++) { |
| 173 | err = nf_register_net_hook(net, ®[i]); |
| 174 | if (err) |
| 175 | goto err; |
| 176 | } |
| 177 | return err; |
| 178 | |
| 179 | err: |
| 180 | if (i > 0) |
| 181 | nf_unregister_net_hooks(net, reg, i); |
| 182 | return err; |
| 183 | } |
| 184 | EXPORT_SYMBOL(nf_register_net_hooks); |
| 185 | |
| 186 | void nf_unregister_net_hooks(struct net *net, const struct nf_hook_ops *reg, |
| 187 | unsigned int n) |
| 188 | { |
| 189 | while (n-- > 0) |
| 190 | nf_unregister_net_hook(net, ®[n]); |
| 191 | } |
| 192 | EXPORT_SYMBOL(nf_unregister_net_hooks); |
| 193 | |
| 194 | static LIST_HEAD(nf_hook_list); |
| 195 | |
| 196 | int nf_register_hook(struct nf_hook_ops *reg) |
| 197 | { |
| 198 | struct net *net, *last; |
| 199 | int ret; |
| 200 | |
| 201 | rtnl_lock(); |
| 202 | for_each_net(net) { |
| 203 | ret = nf_register_net_hook(net, reg); |
| 204 | if (ret && ret != -ENOENT) |
| 205 | goto rollback; |
| 206 | } |
| 207 | list_add_tail(®->list, &nf_hook_list); |
| 208 | rtnl_unlock(); |
| 209 | |
| 210 | return 0; |
| 211 | rollback: |
| 212 | last = net; |
| 213 | for_each_net(net) { |
| 214 | if (net == last) |
| 215 | break; |
| 216 | nf_unregister_net_hook(net, reg); |
| 217 | } |
| 218 | rtnl_unlock(); |
| 219 | return ret; |
| 220 | } |
| 221 | EXPORT_SYMBOL(nf_register_hook); |
| 222 | |
| 223 | void nf_unregister_hook(struct nf_hook_ops *reg) |
| 224 | { |
| 225 | struct net *net; |
| 226 | |
| 227 | rtnl_lock(); |
| 228 | list_del(®->list); |
| 229 | for_each_net(net) |
| 230 | nf_unregister_net_hook(net, reg); |
| 231 | rtnl_unlock(); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 232 | } |
| 233 | EXPORT_SYMBOL(nf_unregister_hook); |
| 234 | |
Patrick McHardy | 972d1cb | 2006-04-06 14:09:12 -0700 | [diff] [blame] | 235 | int nf_register_hooks(struct nf_hook_ops *reg, unsigned int n) |
| 236 | { |
| 237 | unsigned int i; |
| 238 | int err = 0; |
| 239 | |
| 240 | for (i = 0; i < n; i++) { |
| 241 | err = nf_register_hook(®[i]); |
| 242 | if (err) |
| 243 | goto err; |
| 244 | } |
| 245 | return err; |
| 246 | |
| 247 | err: |
| 248 | if (i > 0) |
| 249 | nf_unregister_hooks(reg, i); |
| 250 | return err; |
| 251 | } |
| 252 | EXPORT_SYMBOL(nf_register_hooks); |
| 253 | |
| 254 | void nf_unregister_hooks(struct nf_hook_ops *reg, unsigned int n) |
| 255 | { |
Changli Gao | f68c530 | 2010-10-04 22:24:12 +0200 | [diff] [blame] | 256 | while (n-- > 0) |
| 257 | nf_unregister_hook(®[n]); |
Patrick McHardy | 972d1cb | 2006-04-06 14:09:12 -0700 | [diff] [blame] | 258 | } |
| 259 | EXPORT_SYMBOL(nf_unregister_hooks); |
| 260 | |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 261 | unsigned int nf_iterate(struct list_head *head, |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 262 | struct sk_buff *skb, |
David S. Miller | cfdfab3 | 2015-04-03 16:23:58 -0400 | [diff] [blame] | 263 | struct nf_hook_state *state, |
| 264 | struct nf_hook_ops **elemp) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 265 | { |
| 266 | unsigned int verdict; |
| 267 | |
| 268 | /* |
| 269 | * The caller must not block between calls to this |
| 270 | * function because of risk of continuing from deleted element. |
| 271 | */ |
Michael Wang | 2a6decf | 2012-08-22 19:59:57 +0000 | [diff] [blame] | 272 | list_for_each_entry_continue_rcu((*elemp), head, list) { |
David S. Miller | cfdfab3 | 2015-04-03 16:23:58 -0400 | [diff] [blame] | 273 | if (state->thresh > (*elemp)->priority) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 274 | continue; |
| 275 | |
| 276 | /* Optimization: we don't need to hold module |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 277 | reference here, since function can't sleep. --RR */ |
Patrick McHardy | de9963f | 2011-02-14 17:35:07 +0100 | [diff] [blame] | 278 | repeat: |
Eric W. Biederman | 06198b3 | 2015-09-18 14:33:06 -0500 | [diff] [blame] | 279 | verdict = (*elemp)->hook((*elemp)->priv, skb, state); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 280 | if (verdict != NF_ACCEPT) { |
| 281 | #ifdef CONFIG_NETFILTER_DEBUG |
| 282 | if (unlikely((verdict & NF_VERDICT_MASK) |
| 283 | > NF_MAX_VERDICT)) { |
| 284 | NFDEBUG("Evil return from %p(%u).\n", |
David S. Miller | cfdfab3 | 2015-04-03 16:23:58 -0400 | [diff] [blame] | 285 | (*elemp)->hook, state->hook); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 286 | continue; |
| 287 | } |
| 288 | #endif |
Michael Wang | 2a6decf | 2012-08-22 19:59:57 +0000 | [diff] [blame] | 289 | if (verdict != NF_REPEAT) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 290 | return verdict; |
Patrick McHardy | de9963f | 2011-02-14 17:35:07 +0100 | [diff] [blame] | 291 | goto repeat; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 292 | } |
| 293 | } |
| 294 | return NF_ACCEPT; |
| 295 | } |
| 296 | |
| 297 | |
| 298 | /* Returns 1 if okfn() needs to be executed by the caller, |
Aaron Conole | e2361cb | 2016-09-21 11:35:04 -0400 | [diff] [blame] | 299 | * -EPERM for NF_DROP, 0 otherwise. Caller must hold rcu_read_lock. */ |
David S. Miller | cfdfab3 | 2015-04-03 16:23:58 -0400 | [diff] [blame] | 300 | int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 301 | { |
Michael Wang | 2a6decf | 2012-08-22 19:59:57 +0000 | [diff] [blame] | 302 | struct nf_hook_ops *elem; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 303 | unsigned int verdict; |
| 304 | int ret = 0; |
| 305 | |
Pablo Neira | f719148 | 2015-05-13 18:19:35 +0200 | [diff] [blame] | 306 | elem = list_entry_rcu(state->hook_list, struct nf_hook_ops, list); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 307 | next_hook: |
Pablo Neira | f719148 | 2015-05-13 18:19:35 +0200 | [diff] [blame] | 308 | verdict = nf_iterate(state->hook_list, skb, state, &elem); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 309 | if (verdict == NF_ACCEPT || verdict == NF_STOP) { |
| 310 | ret = 1; |
Eric Paris | da68365 | 2010-11-16 11:52:38 +0000 | [diff] [blame] | 311 | } else if ((verdict & NF_VERDICT_MASK) == NF_DROP) { |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 312 | kfree_skb(skb); |
Florian Westphal | f615df7 | 2011-01-18 15:52:14 +0100 | [diff] [blame] | 313 | ret = NF_DROP_GETERR(verdict); |
Eric Paris | da68365 | 2010-11-16 11:52:38 +0000 | [diff] [blame] | 314 | if (ret == 0) |
| 315 | ret = -EPERM; |
Patrick McHardy | f9c6399 | 2007-12-05 01:27:46 -0800 | [diff] [blame] | 316 | } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE) { |
David S. Miller | cfdfab3 | 2015-04-03 16:23:58 -0400 | [diff] [blame] | 317 | int err = nf_queue(skb, elem, state, |
| 318 | verdict >> NF_VERDICT_QBITS); |
Florian Westphal | 563e123 | 2011-10-31 12:20:16 +0100 | [diff] [blame] | 319 | if (err < 0) { |
Florian Westphal | 563e123 | 2011-10-31 12:20:16 +0100 | [diff] [blame] | 320 | if (err == -ESRCH && |
Florian Westphal | 94b27cc | 2011-01-18 16:08:30 +0100 | [diff] [blame] | 321 | (verdict & NF_VERDICT_FLAG_QUEUE_BYPASS)) |
| 322 | goto next_hook; |
Florian Westphal | 06cdb63 | 2011-01-18 15:28:38 +0100 | [diff] [blame] | 323 | kfree_skb(skb); |
| 324 | } |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 325 | } |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 326 | return ret; |
| 327 | } |
| 328 | EXPORT_SYMBOL(nf_hook_slow); |
| 329 | |
| 330 | |
Herbert Xu | 37d4187 | 2007-10-14 00:39:18 -0700 | [diff] [blame] | 331 | int skb_make_writable(struct sk_buff *skb, unsigned int writable_len) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 332 | { |
Herbert Xu | 37d4187 | 2007-10-14 00:39:18 -0700 | [diff] [blame] | 333 | if (writable_len > skb->len) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 334 | return 0; |
| 335 | |
| 336 | /* Not exclusive use of packet? Must copy. */ |
Herbert Xu | 37d4187 | 2007-10-14 00:39:18 -0700 | [diff] [blame] | 337 | if (!skb_cloned(skb)) { |
| 338 | if (writable_len <= skb_headlen(skb)) |
| 339 | return 1; |
| 340 | } else if (skb_clone_writable(skb, writable_len)) |
| 341 | return 1; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 342 | |
Herbert Xu | 37d4187 | 2007-10-14 00:39:18 -0700 | [diff] [blame] | 343 | if (writable_len <= skb_headlen(skb)) |
| 344 | writable_len = 0; |
| 345 | else |
| 346 | writable_len -= skb_headlen(skb); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 347 | |
Herbert Xu | 37d4187 | 2007-10-14 00:39:18 -0700 | [diff] [blame] | 348 | return !!__pskb_pull_tail(skb, writable_len); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 349 | } |
| 350 | EXPORT_SYMBOL(skb_make_writable); |
| 351 | |
Pablo Neira Ayuso | b7bd180 | 2015-09-30 22:53:44 +0100 | [diff] [blame] | 352 | /* This needs to be compiled in any case to avoid dependencies between the |
| 353 | * nfnetlink_queue code and nf_conntrack. |
| 354 | */ |
Ken-ichirou MATSUZAWA | a4b4766 | 2015-10-05 11:47:13 +0900 | [diff] [blame] | 355 | struct nfnl_ct_hook __rcu *nfnl_ct_hook __read_mostly; |
| 356 | EXPORT_SYMBOL_GPL(nfnl_ct_hook); |
Pablo Neira Ayuso | b7bd180 | 2015-09-30 22:53:44 +0100 | [diff] [blame] | 357 | |
Igor Maravić | c0cd115 | 2011-12-12 02:58:24 +0000 | [diff] [blame] | 358 | #if IS_ENABLED(CONFIG_NF_CONNTRACK) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 359 | /* This does not belong here, but locally generated errors need it if connection |
| 360 | tracking in use: without this, connection may not be in hash table, and hence |
| 361 | manufactured ICMP or RST packets will not be associated with it. */ |
Patrick McHardy | 312a0c16 | 2013-07-28 22:54:08 +0200 | [diff] [blame] | 362 | void (*ip_ct_attach)(struct sk_buff *, const struct sk_buff *) |
| 363 | __rcu __read_mostly; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 364 | EXPORT_SYMBOL(ip_ct_attach); |
| 365 | |
Patrick McHardy | 312a0c16 | 2013-07-28 22:54:08 +0200 | [diff] [blame] | 366 | void nf_ct_attach(struct sk_buff *new, const struct sk_buff *skb) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 367 | { |
Patrick McHardy | 312a0c16 | 2013-07-28 22:54:08 +0200 | [diff] [blame] | 368 | void (*attach)(struct sk_buff *, const struct sk_buff *); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 369 | |
Patrick McHardy | c3a47ab | 2007-02-12 11:09:19 -0800 | [diff] [blame] | 370 | if (skb->nfct) { |
| 371 | rcu_read_lock(); |
| 372 | attach = rcu_dereference(ip_ct_attach); |
| 373 | if (attach) |
| 374 | attach(new, skb); |
| 375 | rcu_read_unlock(); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 376 | } |
| 377 | } |
| 378 | EXPORT_SYMBOL(nf_ct_attach); |
Yasuyuki Kozakai | de6e05c | 2007-03-23 11:17:27 -0700 | [diff] [blame] | 379 | |
Eric Dumazet | 0e60ebe | 2010-11-15 18:17:21 +0100 | [diff] [blame] | 380 | void (*nf_ct_destroy)(struct nf_conntrack *) __rcu __read_mostly; |
Yasuyuki Kozakai | de6e05c | 2007-03-23 11:17:27 -0700 | [diff] [blame] | 381 | EXPORT_SYMBOL(nf_ct_destroy); |
| 382 | |
| 383 | void nf_conntrack_destroy(struct nf_conntrack *nfct) |
| 384 | { |
| 385 | void (*destroy)(struct nf_conntrack *); |
| 386 | |
| 387 | rcu_read_lock(); |
| 388 | destroy = rcu_dereference(nf_ct_destroy); |
| 389 | BUG_ON(destroy == NULL); |
| 390 | destroy(nfct); |
| 391 | rcu_read_unlock(); |
| 392 | } |
| 393 | EXPORT_SYMBOL(nf_conntrack_destroy); |
Pablo Neira Ayuso | 9cb0176 | 2012-06-07 12:13:39 +0200 | [diff] [blame] | 394 | |
Daniel Borkmann | 62da986 | 2015-09-03 01:26:07 +0200 | [diff] [blame] | 395 | /* Built-in default zone used e.g. by modules. */ |
| 396 | const struct nf_conntrack_zone nf_ct_zone_dflt = { |
| 397 | .id = NF_CT_DEFAULT_ZONE_ID, |
| 398 | .dir = NF_CT_DEFAULT_ZONE_DIR, |
| 399 | }; |
| 400 | EXPORT_SYMBOL_GPL(nf_ct_zone_dflt); |
Yasuyuki Kozakai | de6e05c | 2007-03-23 11:17:27 -0700 | [diff] [blame] | 401 | #endif /* CONFIG_NF_CONNTRACK */ |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 402 | |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 403 | #ifdef CONFIG_NF_NAT_NEEDED |
| 404 | void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *); |
| 405 | EXPORT_SYMBOL(nf_nat_decode_session_hook); |
| 406 | #endif |
| 407 | |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 408 | static int nf_register_hook_list(struct net *net) |
| 409 | { |
| 410 | struct nf_hook_ops *elem; |
| 411 | int ret; |
| 412 | |
| 413 | rtnl_lock(); |
| 414 | list_for_each_entry(elem, &nf_hook_list, list) { |
| 415 | ret = nf_register_net_hook(net, elem); |
| 416 | if (ret && ret != -ENOENT) |
| 417 | goto out_undo; |
| 418 | } |
| 419 | rtnl_unlock(); |
| 420 | return 0; |
| 421 | |
| 422 | out_undo: |
| 423 | list_for_each_entry_continue_reverse(elem, &nf_hook_list, list) |
| 424 | nf_unregister_net_hook(net, elem); |
| 425 | rtnl_unlock(); |
| 426 | return ret; |
| 427 | } |
| 428 | |
| 429 | static void nf_unregister_hook_list(struct net *net) |
| 430 | { |
| 431 | struct nf_hook_ops *elem; |
| 432 | |
| 433 | rtnl_lock(); |
| 434 | list_for_each_entry(elem, &nf_hook_list, list) |
| 435 | nf_unregister_net_hook(net, elem); |
| 436 | rtnl_unlock(); |
| 437 | } |
| 438 | |
Gao feng | f3c1a44 | 2013-03-24 23:50:39 +0000 | [diff] [blame] | 439 | static int __net_init netfilter_net_init(struct net *net) |
| 440 | { |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 441 | int i, h, ret; |
| 442 | |
| 443 | for (i = 0; i < ARRAY_SIZE(net->nf.hooks); i++) { |
| 444 | for (h = 0; h < NF_MAX_HOOKS; h++) |
| 445 | INIT_LIST_HEAD(&net->nf.hooks[i][h]); |
| 446 | } |
| 447 | |
Gao feng | f3c1a44 | 2013-03-24 23:50:39 +0000 | [diff] [blame] | 448 | #ifdef CONFIG_PROC_FS |
| 449 | net->nf.proc_netfilter = proc_net_mkdir(net, "netfilter", |
| 450 | net->proc_net); |
Pablo Neira Ayuso | 12202fa | 2013-04-05 19:40:10 +0200 | [diff] [blame] | 451 | if (!net->nf.proc_netfilter) { |
| 452 | if (!net_eq(net, &init_net)) |
| 453 | pr_err("cannot create netfilter proc entry"); |
| 454 | |
Gao feng | f3c1a44 | 2013-03-24 23:50:39 +0000 | [diff] [blame] | 455 | return -ENOMEM; |
| 456 | } |
| 457 | #endif |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 458 | ret = nf_register_hook_list(net); |
| 459 | if (ret) |
| 460 | remove_proc_entry("netfilter", net->proc_net); |
| 461 | |
| 462 | return ret; |
Gao feng | f3c1a44 | 2013-03-24 23:50:39 +0000 | [diff] [blame] | 463 | } |
| 464 | |
| 465 | static void __net_exit netfilter_net_exit(struct net *net) |
| 466 | { |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 467 | nf_unregister_hook_list(net); |
Gao feng | f3c1a44 | 2013-03-24 23:50:39 +0000 | [diff] [blame] | 468 | remove_proc_entry("netfilter", net->proc_net); |
| 469 | } |
| 470 | |
| 471 | static struct pernet_operations netfilter_net_ops = { |
| 472 | .init = netfilter_net_init, |
| 473 | .exit = netfilter_net_exit, |
| 474 | }; |
| 475 | |
Pablo Neira Ayuso | 6d11cfd | 2013-05-22 22:42:36 +0000 | [diff] [blame] | 476 | int __init netfilter_init(void) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 477 | { |
Eric W. Biederman | 085db2c | 2015-07-10 18:15:06 -0500 | [diff] [blame] | 478 | int ret; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 479 | |
Pablo Neira Ayuso | 6d11cfd | 2013-05-22 22:42:36 +0000 | [diff] [blame] | 480 | ret = register_pernet_subsys(&netfilter_net_ops); |
| 481 | if (ret < 0) |
| 482 | goto err; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 483 | |
Pablo Neira Ayuso | 6d11cfd | 2013-05-22 22:42:36 +0000 | [diff] [blame] | 484 | ret = netfilter_log_init(); |
| 485 | if (ret < 0) |
| 486 | goto err_pernet; |
| 487 | |
| 488 | return 0; |
| 489 | err_pernet: |
| 490 | unregister_pernet_subsys(&netfilter_net_ops); |
| 491 | err: |
| 492 | return ret; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 493 | } |