1 #include <linux/kernel.h>
2 #include <linux/init.h>
3 #include <linux/module.h>
4 #include <linux/proc_fs.h>
5 #include <linux/skbuff.h>
6 #include <linux/netfilter.h>
7 #include <linux/seq_file.h>
8 #include <linux/rcupdate.h>
9 #include <net/protocol.h>
10 #include <net/netfilter/nf_queue.h>
12 #include "nf_internals.h"
15 * A queue handler may be registered for each protocol. Each is protected by
16 * long term mutex. The handler must provide an an outfn() to accept packets
17 * for queueing and must reinject all packets it receives, no matter what.
19 static const struct nf_queue_handler *queue_handler[NPROTO];
21 static DEFINE_MUTEX(queue_handler_mutex);
23 /* return EBUSY when somebody else is registered, return EEXIST if the
24 * same handler is registered, return 0 in case of success. */
25 int nf_register_queue_handler(int pf, const struct nf_queue_handler *qh)
32 mutex_lock(&queue_handler_mutex);
33 if (queue_handler[pf] == qh)
35 else if (queue_handler[pf])
38 rcu_assign_pointer(queue_handler[pf], qh);
41 mutex_unlock(&queue_handler_mutex);
45 EXPORT_SYMBOL(nf_register_queue_handler);
47 /* The caller must flush their queue before this */
48 int nf_unregister_queue_handler(int pf, const struct nf_queue_handler *qh)
53 mutex_lock(&queue_handler_mutex);
54 if (queue_handler[pf] != qh) {
55 mutex_unlock(&queue_handler_mutex);
59 rcu_assign_pointer(queue_handler[pf], NULL);
60 mutex_unlock(&queue_handler_mutex);
66 EXPORT_SYMBOL(nf_unregister_queue_handler);
68 void nf_unregister_queue_handlers(const struct nf_queue_handler *qh)
72 mutex_lock(&queue_handler_mutex);
73 for (pf = 0; pf < NPROTO; pf++) {
74 if (queue_handler[pf] == qh)
75 rcu_assign_pointer(queue_handler[pf], NULL);
77 mutex_unlock(&queue_handler_mutex);
81 EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
84 * Any packet that leaves via this function must come back
85 * through nf_reinject().
87 static int __nf_queue(struct sk_buff *skb,
88 struct list_head *elem,
89 int pf, unsigned int hook,
90 struct net_device *indev,
91 struct net_device *outdev,
92 int (*okfn)(struct sk_buff *),
93 unsigned int queuenum)
96 struct nf_queue_entry *entry;
97 #ifdef CONFIG_BRIDGE_NETFILTER
98 struct net_device *physindev = NULL;
99 struct net_device *physoutdev = NULL;
101 struct nf_afinfo *afinfo;
102 const struct nf_queue_handler *qh;
104 /* QUEUE == DROP if noone is waiting, to be safe. */
107 qh = rcu_dereference(queue_handler[pf]);
114 afinfo = nf_get_afinfo(pf);
121 entry = kmalloc(sizeof(*entry) + afinfo->route_key_size, GFP_ATOMIC);
124 printk(KERN_ERR "OOM queueing packet %p\n",
131 *entry = (struct nf_queue_entry) {
133 .elem = list_entry(elem, struct nf_hook_ops, list),
141 /* If it's going away, ignore hook. */
142 if (!try_module_get(entry->elem->owner)) {
148 /* Bump dev refs so they don't vanish while packet is out */
153 #ifdef CONFIG_BRIDGE_NETFILTER
154 if (skb->nf_bridge) {
155 physindev = skb->nf_bridge->physindev;
158 physoutdev = skb->nf_bridge->physoutdev;
160 dev_hold(physoutdev);
163 afinfo->saveroute(skb, entry);
164 status = qh->outfn(entry, queuenum);
169 /* James M doesn't say fuck enough. */
174 #ifdef CONFIG_BRIDGE_NETFILTER
180 module_put(entry->elem->owner);
190 int nf_queue(struct sk_buff *skb,
191 struct list_head *elem,
192 int pf, unsigned int hook,
193 struct net_device *indev,
194 struct net_device *outdev,
195 int (*okfn)(struct sk_buff *),
196 unsigned int queuenum)
198 struct sk_buff *segs;
200 if (!skb_is_gso(skb))
201 return __nf_queue(skb, elem, pf, hook, indev, outdev, okfn,
206 skb->protocol = htons(ETH_P_IP);
209 skb->protocol = htons(ETH_P_IPV6);
213 segs = skb_gso_segment(skb, 0);
215 if (unlikely(IS_ERR(segs)))
219 struct sk_buff *nskb = segs->next;
222 if (!__nf_queue(segs, elem, pf, hook, indev, outdev, okfn,
230 void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
232 struct sk_buff *skb = entry->skb;
233 struct list_head *elem = &entry->elem->list;
234 struct nf_afinfo *afinfo;
238 /* Release those devices we held, or Alexey will kill me. */
240 dev_put(entry->indev);
242 dev_put(entry->outdev);
243 #ifdef CONFIG_BRIDGE_NETFILTER
244 if (skb->nf_bridge) {
245 if (skb->nf_bridge->physindev)
246 dev_put(skb->nf_bridge->physindev);
247 if (skb->nf_bridge->physoutdev)
248 dev_put(skb->nf_bridge->physoutdev);
252 /* Drop reference to owner of hook which queued us. */
253 module_put(entry->elem->owner);
255 /* Continue traversal iff userspace said ok... */
256 if (verdict == NF_REPEAT) {
261 if (verdict == NF_ACCEPT) {
262 afinfo = nf_get_afinfo(entry->pf);
263 if (!afinfo || afinfo->reroute(skb, entry) < 0)
267 if (verdict == NF_ACCEPT) {
269 verdict = nf_iterate(&nf_hooks[entry->pf][entry->hook],
271 entry->indev, entry->outdev, &elem,
272 entry->okfn, INT_MIN);
275 switch (verdict & NF_VERDICT_MASK) {
284 if (!__nf_queue(skb, elem, entry->pf, entry->hook,
285 entry->indev, entry->outdev, entry->okfn,
286 verdict >> NF_VERDICT_BITS))
296 EXPORT_SYMBOL(nf_reinject);
298 #ifdef CONFIG_PROC_FS
299 static void *seq_start(struct seq_file *seq, loff_t *pos)
307 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
317 static void seq_stop(struct seq_file *s, void *v)
322 static int seq_show(struct seq_file *s, void *v)
326 const struct nf_queue_handler *qh;
329 qh = rcu_dereference(queue_handler[*pos]);
331 ret = seq_printf(s, "%2lld NONE\n", *pos);
333 ret = seq_printf(s, "%2lld %s\n", *pos, qh->name);
339 static const struct seq_operations nfqueue_seq_ops = {
346 static int nfqueue_open(struct inode *inode, struct file *file)
348 return seq_open(file, &nfqueue_seq_ops);
351 static const struct file_operations nfqueue_file_ops = {
352 .owner = THIS_MODULE,
353 .open = nfqueue_open,
356 .release = seq_release,
361 int __init netfilter_queue_init(void)
363 #ifdef CONFIG_PROC_FS
364 struct proc_dir_entry *pde;
366 pde = create_proc_entry("nf_queue", S_IRUGO, proc_net_netfilter);
369 pde->proc_fops = &nfqueue_file_ops;