--- /dev/null
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/skbuff.h>
+#include <linux/netfilter.h>
+#include <linux/seq_file.h>
+#include <linux/rcupdate.h>
+#include <net/protocol.h>
+
+#include "nf_internals.h"
+
+/*
+ * A queue handler may be registered for each protocol. Each is protected by
+ * long term mutex. The handler must provide an an outfn() to accept packets
+ * for queueing and must reinject all packets it receives, no matter what.
+ */
+static struct nf_queue_handler *queue_handler[NPROTO];
+
+static DEFINE_RWLOCK(queue_handler_lock);
+
+/* return EBUSY when somebody else is registered, return EEXIST if the
+ * same handler is registered, return 0 in case of success. */
+int nf_register_queue_handler(int pf, struct nf_queue_handler *qh)
+{
+ int ret;
+
+ if (pf >= NPROTO)
+ return -EINVAL;
+
+ write_lock_bh(&queue_handler_lock);
+ if (queue_handler[pf] == qh)
+ ret = -EEXIST;
+ else if (queue_handler[pf])
+ ret = -EBUSY;
+ else {
+ queue_handler[pf] = qh;
+ ret = 0;
+ }
+ write_unlock_bh(&queue_handler_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL(nf_register_queue_handler);
+
+/* The caller must flush their queue before this */
+int nf_unregister_queue_handler(int pf)
+{
+ if (pf >= NPROTO)
+ return -EINVAL;
+
+ write_lock_bh(&queue_handler_lock);
+ queue_handler[pf] = NULL;
+ write_unlock_bh(&queue_handler_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(nf_unregister_queue_handler);
+
+void nf_unregister_queue_handlers(struct nf_queue_handler *qh)
+{
+ int pf;
+
+ write_lock_bh(&queue_handler_lock);
+ for (pf = 0; pf < NPROTO; pf++) {
+ if (queue_handler[pf] == qh)
+ queue_handler[pf] = NULL;
+ }
+ write_unlock_bh(&queue_handler_lock);
+}
+EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
+
+/*
+ * Any packet that leaves via this function must come back
+ * through nf_reinject().
+ */
+int nf_queue(struct sk_buff **skb,
+ struct list_head *elem,
+ int pf, unsigned int hook,
+ struct net_device *indev,
+ struct net_device *outdev,
+ int (*okfn)(struct sk_buff *),
+ unsigned int queuenum)
+{
+ int status;
+ struct nf_info *info;
+#ifdef CONFIG_BRIDGE_NETFILTER
+ struct net_device *physindev = NULL;
+ struct net_device *physoutdev = NULL;
+#endif
+ struct nf_afinfo *afinfo;
+
+ /* QUEUE == DROP if noone is waiting, to be safe. */
+ read_lock(&queue_handler_lock);
+ if (!queue_handler[pf]) {
+ read_unlock(&queue_handler_lock);
+ kfree_skb(*skb);
+ return 1;
+ }
+
+ afinfo = nf_get_afinfo(pf);
+ if (!afinfo) {
+ read_unlock(&queue_handler_lock);
+ kfree_skb(*skb);
+ return 1;
+ }
+
+ info = kmalloc(sizeof(*info) + afinfo->route_key_size, GFP_ATOMIC);
+ if (!info) {
+ if (net_ratelimit())
+ printk(KERN_ERR "OOM queueing packet %p\n",
+ *skb);
+ read_unlock(&queue_handler_lock);
+ kfree_skb(*skb);
+ return 1;
+ }
+
+ *info = (struct nf_info) {
+ (struct nf_hook_ops *)elem, pf, hook, indev, outdev, okfn };
+
+ /* If it's going away, ignore hook. */
+ if (!try_module_get(info->elem->owner)) {
+ read_unlock(&queue_handler_lock);
+ kfree(info);
+ return 0;
+ }
+
+ /* Bump dev refs so they don't vanish while packet is out */
+ if (indev) dev_hold(indev);
+ if (outdev) dev_hold(outdev);
+
+#ifdef CONFIG_BRIDGE_NETFILTER
+ if ((*skb)->nf_bridge) {
+ physindev = (*skb)->nf_bridge->physindev;
+ if (physindev) dev_hold(physindev);
+ physoutdev = (*skb)->nf_bridge->physoutdev;
+ if (physoutdev) dev_hold(physoutdev);
+ }
+#endif
+ afinfo->saveroute(*skb, info);
+ status = queue_handler[pf]->outfn(*skb, info, queuenum,
+ queue_handler[pf]->data);
+
+ read_unlock(&queue_handler_lock);
+
+ if (status < 0) {
+ /* James M doesn't say fuck enough. */
+ if (indev) dev_put(indev);
+ if (outdev) dev_put(outdev);
+#ifdef CONFIG_BRIDGE_NETFILTER
+ if (physindev) dev_put(physindev);
+ if (physoutdev) dev_put(physoutdev);
+#endif
+ module_put(info->elem->owner);
+ kfree(info);
+ kfree_skb(*skb);
+
+ return 1;
+ }
+
+ return 1;
+}
+
+void nf_reinject(struct sk_buff *skb, struct nf_info *info,
+ unsigned int verdict)
+{
+ struct list_head *elem = &info->elem->list;
+ struct list_head *i;
+ struct nf_afinfo *afinfo;
+
+ rcu_read_lock();
+
+ /* Release those devices we held, or Alexey will kill me. */
+ if (info->indev) dev_put(info->indev);
+ if (info->outdev) dev_put(info->outdev);
+#ifdef CONFIG_BRIDGE_NETFILTER
+ if (skb->nf_bridge) {
+ if (skb->nf_bridge->physindev)
+ dev_put(skb->nf_bridge->physindev);
+ if (skb->nf_bridge->physoutdev)
+ dev_put(skb->nf_bridge->physoutdev);
+ }
+#endif
+
+ /* Drop reference to owner of hook which queued us. */
+ module_put(info->elem->owner);
+
+ list_for_each_rcu(i, &nf_hooks[info->pf][info->hook]) {
+ if (i == elem)
+ break;
+ }
+
+ if (i == &nf_hooks[info->pf][info->hook]) {
+ /* The module which sent it to userspace is gone. */
+ NFDEBUG("%s: module disappeared, dropping packet.\n",
+ __FUNCTION__);
+ verdict = NF_DROP;
+ }
+
+ /* Continue traversal iff userspace said ok... */
+ if (verdict == NF_REPEAT) {
+ elem = elem->prev;
+ verdict = NF_ACCEPT;
+ }
+
+ if (verdict == NF_ACCEPT) {
+ afinfo = nf_get_afinfo(info->pf);
+ if (!afinfo || afinfo->reroute(&skb, info) < 0)
+ verdict = NF_DROP;
+ }
+
+ if (verdict == NF_ACCEPT) {
+ next_hook:
+ verdict = nf_iterate(&nf_hooks[info->pf][info->hook],
+ &skb, info->hook,
+ info->indev, info->outdev, &elem,
+ info->okfn, INT_MIN);
+ }
+
+ switch (verdict & NF_VERDICT_MASK) {
+ case NF_ACCEPT:
+ info->okfn(skb);
+ break;
+
+ case NF_QUEUE:
+ if (!nf_queue(&skb, elem, info->pf, info->hook,
+ info->indev, info->outdev, info->okfn,
+ verdict >> NF_VERDICT_BITS))
+ goto next_hook;
+ break;
+ }
+ rcu_read_unlock();
+
+ if (verdict == NF_DROP)
+ kfree_skb(skb);
+
+ kfree(info);
+ return;
+}
+EXPORT_SYMBOL(nf_reinject);
+
+#ifdef CONFIG_PROC_FS
+static void *seq_start(struct seq_file *seq, loff_t *pos)
+{
+ if (*pos >= NPROTO)
+ return NULL;
+
+ return pos;
+}
+
+static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+ (*pos)++;
+
+ if (*pos >= NPROTO)
+ return NULL;
+
+ return pos;
+}
+
+static void seq_stop(struct seq_file *s, void *v)
+{
+
+}
+
+static int seq_show(struct seq_file *s, void *v)
+{
+ int ret;
+ loff_t *pos = v;
+ struct nf_queue_handler *qh;
+
+ read_lock_bh(&queue_handler_lock);
+ qh = queue_handler[*pos];
+ if (!qh)
+ ret = seq_printf(s, "%2lld NONE\n", *pos);
+ else
+ ret = seq_printf(s, "%2lld %s\n", *pos, qh->name);
+ read_unlock_bh(&queue_handler_lock);
+
+ return ret;
+}
+
+static struct seq_operations nfqueue_seq_ops = {
+ .start = seq_start,
+ .next = seq_next,
+ .stop = seq_stop,
+ .show = seq_show,
+};
+
+static int nfqueue_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &nfqueue_seq_ops);
+}
+
+static struct file_operations nfqueue_file_ops = {
+ .owner = THIS_MODULE,
+ .open = nfqueue_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+#endif /* PROC_FS */
+
+
+int __init netfilter_queue_init(void)
+{
+#ifdef CONFIG_PROC_FS
+ struct proc_dir_entry *pde;
+
+ pde = create_proc_entry("nf_queue", S_IRUGO, proc_net_netfilter);
+ if (!pde)
+ return -1;
+ pde->proc_fops = &nfqueue_file_ops;
+#endif
+ return 0;
+}
+
git://git.onelab.eu / linux-2.6.git / blobdiff