Patrick McHardy | f229f6c | 2013-04-06 15:24:29 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Rusty Russell (C)2000 -- This code is GPL. |
| 3 | * Patrick McHardy (c) 2006-2012 |
| 4 | */ |
| 5 | |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 6 | #include <linux/kernel.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 7 | #include <linux/slab.h> |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 8 | #include <linux/init.h> |
| 9 | #include <linux/module.h> |
| 10 | #include <linux/proc_fs.h> |
| 11 | #include <linux/skbuff.h> |
| 12 | #include <linux/netfilter.h> |
Harald Welte | bbd86b9f | 2005-08-09 20:23:11 -0700 | [diff] [blame] | 13 | #include <linux/seq_file.h> |
Patrick McHardy | 7a11b98 | 2006-02-27 13:03:24 -0800 | [diff] [blame] | 14 | #include <linux/rcupdate.h> |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 15 | #include <net/protocol.h> |
Patrick McHardy | c01cd42 | 2007-12-05 01:24:48 -0800 | [diff] [blame] | 16 | #include <net/netfilter/nf_queue.h> |
Eric Dumazet | 7fee226 | 2010-05-11 23:19:48 +0000 | [diff] [blame] | 17 | #include <net/dst.h> |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 18 | |
| 19 | #include "nf_internals.h" |
| 20 | |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 21 | /* |
Florian Westphal | 0360ae4 | 2012-11-23 06:22:21 +0000 | [diff] [blame] | 22 | * Hook for nfnetlink_queue to register its queue handler. |
| 23 | * We do this so that most of the NFQUEUE code can be modular. |
| 24 | * |
| 25 | * Once the queue is registered it must reinject all packets it |
| 26 | * receives, no matter what. |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 27 | */ |
Florian Westphal | 0360ae4 | 2012-11-23 06:22:21 +0000 | [diff] [blame] | 28 | static const struct nf_queue_handler __rcu *queue_handler __read_mostly; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 29 | |
Harald Welte | d72367b | 2005-08-09 20:23:36 -0700 | [diff] [blame] | 30 | /* return EBUSY when somebody else is registered, return EEXIST if the |
| 31 | * same handler is registered, return 0 in case of success. */ |
Florian Westphal | 0360ae4 | 2012-11-23 06:22:21 +0000 | [diff] [blame] | 32 | void nf_register_queue_handler(const struct nf_queue_handler *qh) |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 33 | { |
Florian Westphal | 0360ae4 | 2012-11-23 06:22:21 +0000 | [diff] [blame] | 34 | /* should never happen, we only have one queueing backend in kernel */ |
| 35 | WARN_ON(rcu_access_pointer(queue_handler)); |
| 36 | rcu_assign_pointer(queue_handler, qh); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 37 | } |
| 38 | EXPORT_SYMBOL(nf_register_queue_handler); |
| 39 | |
| 40 | /* The caller must flush their queue before this */ |
Florian Westphal | 0360ae4 | 2012-11-23 06:22:21 +0000 | [diff] [blame] | 41 | void nf_unregister_queue_handler(void) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 42 | { |
Florian Westphal | 0360ae4 | 2012-11-23 06:22:21 +0000 | [diff] [blame] | 43 | RCU_INIT_POINTER(queue_handler, NULL); |
Yasuyuki Kozakai | 585426f | 2007-07-07 22:40:26 -0700 | [diff] [blame] | 44 | synchronize_rcu(); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 45 | } |
| 46 | EXPORT_SYMBOL(nf_unregister_queue_handler); |
| 47 | |
Florian Westphal | a5fedd43 | 2013-04-19 04:58:25 +0000 | [diff] [blame] | 48 | void nf_queue_entry_release_refs(struct nf_queue_entry *entry) |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 49 | { |
| 50 | /* Release those devices we held, or Alexey will kill me. */ |
| 51 | if (entry->indev) |
| 52 | dev_put(entry->indev); |
| 53 | if (entry->outdev) |
| 54 | dev_put(entry->outdev); |
| 55 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 56 | if (entry->skb->nf_bridge) { |
| 57 | struct nf_bridge_info *nf_bridge = entry->skb->nf_bridge; |
| 58 | |
| 59 | if (nf_bridge->physindev) |
| 60 | dev_put(nf_bridge->physindev); |
| 61 | if (nf_bridge->physoutdev) |
| 62 | dev_put(nf_bridge->physoutdev); |
| 63 | } |
| 64 | #endif |
| 65 | /* Drop reference to owner of hook which queued us. */ |
| 66 | module_put(entry->elem->owner); |
| 67 | } |
Florian Westphal | a5fedd43 | 2013-04-19 04:58:25 +0000 | [diff] [blame] | 68 | EXPORT_SYMBOL_GPL(nf_queue_entry_release_refs); |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 69 | |
Florian Westphal | 4bd6044 | 2013-04-19 04:58:23 +0000 | [diff] [blame] | 70 | /* Bump dev refs so they don't vanish while packet is out */ |
Florian Westphal | a5fedd43 | 2013-04-19 04:58:25 +0000 | [diff] [blame] | 71 | bool nf_queue_entry_get_refs(struct nf_queue_entry *entry) |
Florian Westphal | 4bd6044 | 2013-04-19 04:58:23 +0000 | [diff] [blame] | 72 | { |
| 73 | if (!try_module_get(entry->elem->owner)) |
| 74 | return false; |
| 75 | |
| 76 | if (entry->indev) |
| 77 | dev_hold(entry->indev); |
| 78 | if (entry->outdev) |
| 79 | dev_hold(entry->outdev); |
| 80 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 81 | if (entry->skb->nf_bridge) { |
| 82 | struct nf_bridge_info *nf_bridge = entry->skb->nf_bridge; |
| 83 | struct net_device *physdev; |
| 84 | |
| 85 | physdev = nf_bridge->physindev; |
| 86 | if (physdev) |
| 87 | dev_hold(physdev); |
| 88 | physdev = nf_bridge->physoutdev; |
| 89 | if (physdev) |
| 90 | dev_hold(physdev); |
| 91 | } |
| 92 | #endif |
| 93 | |
| 94 | return true; |
| 95 | } |
Florian Westphal | a5fedd43 | 2013-04-19 04:58:25 +0000 | [diff] [blame] | 96 | EXPORT_SYMBOL_GPL(nf_queue_entry_get_refs); |
Florian Westphal | 4bd6044 | 2013-04-19 04:58:23 +0000 | [diff] [blame] | 97 | |
YOSHIFUJI Hideaki | 601e68e | 2007-02-12 11:15:49 -0800 | [diff] [blame] | 98 | /* |
| 99 | * Any packet that leaves via this function must come back |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 100 | * through nf_reinject(). |
| 101 | */ |
Florian Westphal | a5fedd43 | 2013-04-19 04:58:25 +0000 | [diff] [blame] | 102 | int nf_queue(struct sk_buff *skb, |
Michael Wang | 1c15b67 | 2012-08-22 20:00:06 +0000 | [diff] [blame] | 103 | struct nf_hook_ops *elem, |
Jan Engelhardt | 76108ce | 2008-10-08 11:35:00 +0200 | [diff] [blame] | 104 | u_int8_t pf, unsigned int hook, |
Patrick McHardy | 394f545 | 2006-08-05 00:58:52 -0700 | [diff] [blame] | 105 | struct net_device *indev, |
| 106 | struct net_device *outdev, |
| 107 | int (*okfn)(struct sk_buff *), |
| 108 | unsigned int queuenum) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 109 | { |
Florian Westphal | f158508 | 2011-01-18 15:27:28 +0100 | [diff] [blame] | 110 | int status = -ENOENT; |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 111 | struct nf_queue_entry *entry = NULL; |
Patrick McHardy | 1e796fd | 2007-12-17 22:42:27 -0800 | [diff] [blame] | 112 | const struct nf_afinfo *afinfo; |
Patrick McHardy | e3ac529 | 2007-12-05 01:23:57 -0800 | [diff] [blame] | 113 | const struct nf_queue_handler *qh; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 114 | |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 115 | /* QUEUE == DROP if no one is waiting, to be safe. */ |
Yasuyuki Kozakai | 585426f | 2007-07-07 22:40:26 -0700 | [diff] [blame] | 116 | rcu_read_lock(); |
| 117 | |
Florian Westphal | 0360ae4 | 2012-11-23 06:22:21 +0000 | [diff] [blame] | 118 | qh = rcu_dereference(queue_handler); |
Florian Westphal | 94b27cc | 2011-01-18 16:08:30 +0100 | [diff] [blame] | 119 | if (!qh) { |
| 120 | status = -ESRCH; |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 121 | goto err_unlock; |
Florian Westphal | 94b27cc | 2011-01-18 16:08:30 +0100 | [diff] [blame] | 122 | } |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 123 | |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 124 | afinfo = nf_get_afinfo(pf); |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 125 | if (!afinfo) |
| 126 | goto err_unlock; |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 127 | |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 128 | entry = kmalloc(sizeof(*entry) + afinfo->route_key_size, GFP_ATOMIC); |
Florian Westphal | f158508 | 2011-01-18 15:27:28 +0100 | [diff] [blame] | 129 | if (!entry) { |
| 130 | status = -ENOMEM; |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 131 | goto err_unlock; |
Florian Westphal | f158508 | 2011-01-18 15:27:28 +0100 | [diff] [blame] | 132 | } |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 133 | |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 134 | *entry = (struct nf_queue_entry) { |
| 135 | .skb = skb, |
Michael Wang | 1c15b67 | 2012-08-22 20:00:06 +0000 | [diff] [blame] | 136 | .elem = elem, |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 137 | .pf = pf, |
| 138 | .hook = hook, |
| 139 | .indev = indev, |
| 140 | .outdev = outdev, |
| 141 | .okfn = okfn, |
Florian Westphal | a5fedd43 | 2013-04-19 04:58:25 +0000 | [diff] [blame] | 142 | .size = sizeof(*entry) + afinfo->route_key_size, |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 143 | }; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 144 | |
Florian Westphal | 4bd6044 | 2013-04-19 04:58:23 +0000 | [diff] [blame] | 145 | if (!nf_queue_entry_get_refs(entry)) { |
Florian Westphal | 06cdb63 | 2011-01-18 15:28:38 +0100 | [diff] [blame] | 146 | status = -ECANCELED; |
| 147 | goto err_unlock; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 148 | } |
Eric Dumazet | 7fee226 | 2010-05-11 23:19:48 +0000 | [diff] [blame] | 149 | skb_dst_force(skb); |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 150 | afinfo->saveroute(skb, entry); |
| 151 | status = qh->outfn(entry, queuenum); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 152 | |
Yasuyuki Kozakai | 585426f | 2007-07-07 22:40:26 -0700 | [diff] [blame] | 153 | rcu_read_unlock(); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 154 | |
| 155 | if (status < 0) { |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 156 | nf_queue_entry_release_refs(entry); |
| 157 | goto err; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 158 | } |
| 159 | |
Florian Westphal | f158508 | 2011-01-18 15:27:28 +0100 | [diff] [blame] | 160 | return 0; |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 161 | |
| 162 | err_unlock: |
| 163 | rcu_read_unlock(); |
| 164 | err: |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 165 | kfree(entry); |
Florian Westphal | f158508 | 2011-01-18 15:27:28 +0100 | [diff] [blame] | 166 | return status; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 167 | } |
| 168 | |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 169 | void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict) |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 170 | { |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 171 | struct sk_buff *skb = entry->skb; |
Michael Wang | 2a6decf | 2012-08-22 19:59:57 +0000 | [diff] [blame] | 172 | struct nf_hook_ops *elem = entry->elem; |
Patrick McHardy | 1e796fd | 2007-12-17 22:42:27 -0800 | [diff] [blame] | 173 | const struct nf_afinfo *afinfo; |
Florian Westphal | f158508 | 2011-01-18 15:27:28 +0100 | [diff] [blame] | 174 | int err; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 175 | |
| 176 | rcu_read_lock(); |
| 177 | |
Patrick McHardy | daaa8be | 2007-12-05 01:27:19 -0800 | [diff] [blame] | 178 | nf_queue_entry_release_refs(entry); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 179 | |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 180 | /* Continue traversal iff userspace said ok... */ |
| 181 | if (verdict == NF_REPEAT) { |
Michael Wang | 2a6decf | 2012-08-22 19:59:57 +0000 | [diff] [blame] | 182 | elem = list_entry(elem->list.prev, struct nf_hook_ops, list); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 183 | verdict = NF_ACCEPT; |
| 184 | } |
| 185 | |
| 186 | if (verdict == NF_ACCEPT) { |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 187 | afinfo = nf_get_afinfo(entry->pf); |
| 188 | if (!afinfo || afinfo->reroute(skb, entry) < 0) |
Patrick McHardy | 7a11b98 | 2006-02-27 13:03:24 -0800 | [diff] [blame] | 189 | verdict = NF_DROP; |
| 190 | } |
| 191 | |
| 192 | if (verdict == NF_ACCEPT) { |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 193 | next_hook: |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 194 | verdict = nf_iterate(&nf_hooks[entry->pf][entry->hook], |
| 195 | skb, entry->hook, |
| 196 | entry->indev, entry->outdev, &elem, |
| 197 | entry->okfn, INT_MIN); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 198 | } |
| 199 | |
| 200 | switch (verdict & NF_VERDICT_MASK) { |
| 201 | case NF_ACCEPT: |
Patrick McHardy | 3bc3871 | 2006-07-24 22:52:47 -0700 | [diff] [blame] | 202 | case NF_STOP: |
Patrick McHardy | 4b3d15e | 2007-12-05 01:27:02 -0800 | [diff] [blame] | 203 | local_bh_disable(); |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 204 | entry->okfn(skb); |
Patrick McHardy | 4b3d15e | 2007-12-05 01:27:02 -0800 | [diff] [blame] | 205 | local_bh_enable(); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 206 | break; |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 207 | case NF_QUEUE: |
Florian Westphal | a5fedd43 | 2013-04-19 04:58:25 +0000 | [diff] [blame] | 208 | err = nf_queue(skb, elem, entry->pf, entry->hook, |
| 209 | entry->indev, entry->outdev, entry->okfn, |
| 210 | verdict >> NF_VERDICT_QBITS); |
Florian Westphal | 06cdb63 | 2011-01-18 15:28:38 +0100 | [diff] [blame] | 211 | if (err < 0) { |
| 212 | if (err == -ECANCELED) |
| 213 | goto next_hook; |
Florian Westphal | 94b27cc | 2011-01-18 16:08:30 +0100 | [diff] [blame] | 214 | if (err == -ESRCH && |
| 215 | (verdict & NF_VERDICT_FLAG_QUEUE_BYPASS)) |
| 216 | goto next_hook; |
Florian Westphal | 06cdb63 | 2011-01-18 15:28:38 +0100 | [diff] [blame] | 217 | kfree_skb(skb); |
| 218 | } |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 219 | break; |
Eric Dumazet | 64507fd | 2010-02-19 15:28:38 +0100 | [diff] [blame] | 220 | case NF_STOLEN: |
Julian Anastasov | fad5444 | 2011-08-05 00:36:28 +0000 | [diff] [blame] | 221 | break; |
Patrick McHardy | 3bc3871 | 2006-07-24 22:52:47 -0700 | [diff] [blame] | 222 | default: |
| 223 | kfree_skb(skb); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 224 | } |
| 225 | rcu_read_unlock(); |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 226 | kfree(entry); |
Harald Welte | f6ebe77 | 2005-08-09 20:21:49 -0700 | [diff] [blame] | 227 | } |
| 228 | EXPORT_SYMBOL(nf_reinject); |