bbd86b9fc4
This patch adds a /proc/net/netfilter/nf_queue file, similar to the recently-added /proc/net/netfilter/nf_log. It indicates which queue handler is registered to which protocol family. This is useful since there are now multiple queue handlers in the treee (ip[6]_queue, nfnetlink_queue). Signed-off-by: Harald Welte <laforge@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
1133 lines
26 KiB
C
1133 lines
26 KiB
C
/*
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* This is a module which is used for queueing packets and communicating with
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* userspace via nfetlink.
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*
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* (C) 2005 by Harald Welte <laforge@netfilter.org>
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*
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* Based on the old ipv4-only ip_queue.c:
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* (C) 2000-2002 James Morris <jmorris@intercode.com.au>
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* (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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*/
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#include <linux/module.h>
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#include <linux/skbuff.h>
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#include <linux/init.h>
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#include <linux/spinlock.h>
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#include <linux/notifier.h>
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#include <linux/netdevice.h>
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#include <linux/netfilter.h>
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#include <linux/proc_fs.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/netfilter_ipv6.h>
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#include <linux/netfilter/nfnetlink.h>
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#include <linux/netfilter/nfnetlink_queue.h>
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#include <linux/list.h>
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#include <net/sock.h>
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#include <asm/atomic.h>
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#ifdef CONFIG_BRIDGE_NETFILTER
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#include "../bridge/br_private.h"
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#endif
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#define NFQNL_QMAX_DEFAULT 1024
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#if 0
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#define QDEBUG(x, args ...) printk(KERN_DEBUG "%s(%d):%s(): " x, \
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__FILE__, __LINE__, __FUNCTION__, \
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## args)
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#else
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#define QDEBUG(x, ...)
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#endif
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struct nfqnl_queue_entry {
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struct list_head list;
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struct nf_info *info;
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struct sk_buff *skb;
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unsigned int id;
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};
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struct nfqnl_instance {
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struct hlist_node hlist; /* global list of queues */
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atomic_t use;
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int peer_pid;
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unsigned int queue_maxlen;
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unsigned int copy_range;
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unsigned int queue_total;
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unsigned int queue_dropped;
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unsigned int queue_user_dropped;
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atomic_t id_sequence; /* 'sequence' of pkt ids */
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u_int16_t queue_num; /* number of this queue */
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u_int8_t copy_mode;
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spinlock_t lock;
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struct list_head queue_list; /* packets in queue */
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};
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typedef int (*nfqnl_cmpfn)(struct nfqnl_queue_entry *, unsigned long);
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static DEFINE_RWLOCK(instances_lock);
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u_int64_t htonll(u_int64_t in)
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{
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u_int64_t out;
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int i;
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for (i = 0; i < sizeof(u_int64_t); i++)
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((u_int8_t *)&out)[sizeof(u_int64_t)-1] = ((u_int8_t *)&in)[i];
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return out;
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}
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#define INSTANCE_BUCKETS 16
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static struct hlist_head instance_table[INSTANCE_BUCKETS];
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static inline u_int8_t instance_hashfn(u_int16_t queue_num)
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{
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return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS;
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}
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static struct nfqnl_instance *
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__instance_lookup(u_int16_t queue_num)
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{
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struct hlist_head *head;
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struct hlist_node *pos;
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struct nfqnl_instance *inst;
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head = &instance_table[instance_hashfn(queue_num)];
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hlist_for_each_entry(inst, pos, head, hlist) {
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if (inst->queue_num == queue_num)
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return inst;
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}
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return NULL;
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}
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static struct nfqnl_instance *
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instance_lookup_get(u_int16_t queue_num)
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{
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struct nfqnl_instance *inst;
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read_lock_bh(&instances_lock);
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inst = __instance_lookup(queue_num);
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if (inst)
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atomic_inc(&inst->use);
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read_unlock_bh(&instances_lock);
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return inst;
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}
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static void
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instance_put(struct nfqnl_instance *inst)
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{
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if (inst && atomic_dec_and_test(&inst->use)) {
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QDEBUG("kfree(inst=%p)\n", inst);
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kfree(inst);
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}
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}
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static struct nfqnl_instance *
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instance_create(u_int16_t queue_num, int pid)
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{
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struct nfqnl_instance *inst;
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QDEBUG("entering for queue_num=%u, pid=%d\n", queue_num, pid);
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write_lock_bh(&instances_lock);
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if (__instance_lookup(queue_num)) {
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inst = NULL;
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QDEBUG("aborting, instance already exists\n");
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goto out_unlock;
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}
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inst = kmalloc(sizeof(*inst), GFP_ATOMIC);
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if (!inst)
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goto out_unlock;
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memset(inst, 0, sizeof(*inst));
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inst->queue_num = queue_num;
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inst->peer_pid = pid;
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inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
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inst->copy_range = 0xfffff;
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inst->copy_mode = NFQNL_COPY_NONE;
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atomic_set(&inst->id_sequence, 0);
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/* needs to be two, since we _put() after creation */
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atomic_set(&inst->use, 2);
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inst->lock = SPIN_LOCK_UNLOCKED;
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INIT_LIST_HEAD(&inst->queue_list);
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if (!try_module_get(THIS_MODULE))
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goto out_free;
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hlist_add_head(&inst->hlist,
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&instance_table[instance_hashfn(queue_num)]);
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write_unlock_bh(&instances_lock);
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QDEBUG("successfully created new instance\n");
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return inst;
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out_free:
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kfree(inst);
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out_unlock:
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write_unlock_bh(&instances_lock);
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return NULL;
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}
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static void nfqnl_flush(struct nfqnl_instance *queue, int verdict);
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static void
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_instance_destroy2(struct nfqnl_instance *inst, int lock)
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{
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/* first pull it out of the global list */
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if (lock)
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write_lock_bh(&instances_lock);
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QDEBUG("removing instance %p (queuenum=%u) from hash\n",
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inst, inst->queue_num);
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hlist_del(&inst->hlist);
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if (lock)
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write_unlock_bh(&instances_lock);
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/* then flush all pending skbs from the queue */
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nfqnl_flush(inst, NF_DROP);
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/* and finally put the refcount */
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instance_put(inst);
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module_put(THIS_MODULE);
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}
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static inline void
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__instance_destroy(struct nfqnl_instance *inst)
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{
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_instance_destroy2(inst, 0);
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}
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static inline void
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instance_destroy(struct nfqnl_instance *inst)
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{
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_instance_destroy2(inst, 1);
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}
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static void
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issue_verdict(struct nfqnl_queue_entry *entry, int verdict)
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{
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QDEBUG("entering for entry %p, verdict %u\n", entry, verdict);
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/* TCP input path (and probably other bits) assume to be called
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* from softirq context, not from syscall, like issue_verdict is
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* called. TCP input path deadlocks with locks taken from timer
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* softirq, e.g. We therefore emulate this by local_bh_disable() */
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local_bh_disable();
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nf_reinject(entry->skb, entry->info, verdict);
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local_bh_enable();
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kfree(entry);
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}
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static inline void
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__enqueue_entry(struct nfqnl_instance *queue,
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struct nfqnl_queue_entry *entry)
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{
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list_add(&entry->list, &queue->queue_list);
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queue->queue_total++;
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}
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/*
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* Find and return a queued entry matched by cmpfn, or return the last
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* entry if cmpfn is NULL.
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*/
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static inline struct nfqnl_queue_entry *
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__find_entry(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
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unsigned long data)
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{
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struct list_head *p;
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list_for_each_prev(p, &queue->queue_list) {
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struct nfqnl_queue_entry *entry = (struct nfqnl_queue_entry *)p;
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if (!cmpfn || cmpfn(entry, data))
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return entry;
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}
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return NULL;
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}
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static inline void
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__dequeue_entry(struct nfqnl_instance *q, struct nfqnl_queue_entry *entry)
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{
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list_del(&entry->list);
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q->queue_total--;
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}
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static inline struct nfqnl_queue_entry *
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__find_dequeue_entry(struct nfqnl_instance *queue,
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nfqnl_cmpfn cmpfn, unsigned long data)
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{
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struct nfqnl_queue_entry *entry;
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entry = __find_entry(queue, cmpfn, data);
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if (entry == NULL)
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return NULL;
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__dequeue_entry(queue, entry);
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return entry;
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}
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static inline void
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__nfqnl_flush(struct nfqnl_instance *queue, int verdict)
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{
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struct nfqnl_queue_entry *entry;
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while ((entry = __find_dequeue_entry(queue, NULL, 0)))
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issue_verdict(entry, verdict);
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}
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static inline int
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__nfqnl_set_mode(struct nfqnl_instance *queue,
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unsigned char mode, unsigned int range)
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{
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int status = 0;
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switch (mode) {
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case NFQNL_COPY_NONE:
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case NFQNL_COPY_META:
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queue->copy_mode = mode;
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queue->copy_range = 0;
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break;
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case NFQNL_COPY_PACKET:
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queue->copy_mode = mode;
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/* we're using struct nfattr which has 16bit nfa_len */
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if (range > 0xffff)
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queue->copy_range = 0xffff;
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else
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queue->copy_range = range;
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break;
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default:
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status = -EINVAL;
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}
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return status;
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}
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static struct nfqnl_queue_entry *
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find_dequeue_entry(struct nfqnl_instance *queue,
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nfqnl_cmpfn cmpfn, unsigned long data)
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{
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struct nfqnl_queue_entry *entry;
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spin_lock_bh(&queue->lock);
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entry = __find_dequeue_entry(queue, cmpfn, data);
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spin_unlock_bh(&queue->lock);
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return entry;
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}
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static void
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nfqnl_flush(struct nfqnl_instance *queue, int verdict)
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{
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spin_lock_bh(&queue->lock);
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__nfqnl_flush(queue, verdict);
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spin_unlock_bh(&queue->lock);
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}
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static struct sk_buff *
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nfqnl_build_packet_message(struct nfqnl_instance *queue,
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struct nfqnl_queue_entry *entry, int *errp)
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{
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unsigned char *old_tail;
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size_t size;
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size_t data_len = 0;
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struct sk_buff *skb;
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struct nfqnl_msg_packet_hdr pmsg;
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struct nlmsghdr *nlh;
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struct nfgenmsg *nfmsg;
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unsigned int tmp_uint;
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QDEBUG("entered\n");
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/* all macros expand to constant values at compile time */
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size = NLMSG_SPACE(sizeof(struct nfqnl_msg_packet_hdr))
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+ NLMSG_SPACE(sizeof(u_int32_t)) /* ifindex */
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+ NLMSG_SPACE(sizeof(u_int32_t)) /* ifindex */
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#ifdef CONFIG_BRIDGE_NETFILTER
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+ NLMSG_SPACE(sizeof(u_int32_t)) /* ifindex */
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+ NLMSG_SPACE(sizeof(u_int32_t)) /* ifindex */
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#endif
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+ NLMSG_SPACE(sizeof(u_int32_t)) /* mark */
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+ NLMSG_SPACE(sizeof(struct nfqnl_msg_packet_hw))
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+ NLMSG_SPACE(sizeof(struct nfqnl_msg_packet_timestamp));
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spin_lock_bh(&queue->lock);
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switch (queue->copy_mode) {
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case NFQNL_COPY_META:
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case NFQNL_COPY_NONE:
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data_len = 0;
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break;
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case NFQNL_COPY_PACKET:
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if (queue->copy_range == 0
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|| queue->copy_range > entry->skb->len)
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data_len = entry->skb->len;
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else
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data_len = queue->copy_range;
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size += NLMSG_SPACE(data_len);
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break;
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default:
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*errp = -EINVAL;
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spin_unlock_bh(&queue->lock);
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return NULL;
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}
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spin_unlock_bh(&queue->lock);
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skb = alloc_skb(size, GFP_ATOMIC);
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if (!skb)
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goto nlmsg_failure;
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old_tail= skb->tail;
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nlh = NLMSG_PUT(skb, 0, 0,
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NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
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sizeof(struct nfgenmsg));
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nfmsg = NLMSG_DATA(nlh);
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nfmsg->nfgen_family = entry->info->pf;
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nfmsg->version = NFNETLINK_V0;
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nfmsg->res_id = htons(queue->queue_num);
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pmsg.packet_id = htonl(entry->id);
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pmsg.hw_protocol = htons(entry->skb->protocol);
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pmsg.hook = entry->info->hook;
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NFA_PUT(skb, NFQA_PACKET_HDR, sizeof(pmsg), &pmsg);
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if (entry->info->indev) {
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tmp_uint = htonl(entry->info->indev->ifindex);
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#ifndef CONFIG_BRIDGE_NETFILTER
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NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint), &tmp_uint);
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#else
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if (entry->info->pf == PF_BRIDGE) {
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/* Case 1: indev is physical input device, we need to
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* look for bridge group (when called from
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* netfilter_bridge) */
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NFA_PUT(skb, NFQA_IFINDEX_PHYSINDEV, sizeof(tmp_uint),
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&tmp_uint);
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/* this is the bridge group "brX" */
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tmp_uint = htonl(entry->info->indev->br_port->br->dev->ifindex);
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NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint),
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&tmp_uint);
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} else {
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/* Case 2: indev is bridge group, we need to look for
|
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* physical device (when called from ipv4) */
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NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint),
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&tmp_uint);
|
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if (entry->skb->nf_bridge
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&& entry->skb->nf_bridge->physindev) {
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tmp_uint = htonl(entry->skb->nf_bridge->physindev->ifindex);
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NFA_PUT(skb, NFQA_IFINDEX_PHYSINDEV,
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sizeof(tmp_uint), &tmp_uint);
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}
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}
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#endif
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}
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|
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if (entry->info->outdev) {
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tmp_uint = htonl(entry->info->outdev->ifindex);
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#ifndef CONFIG_BRIDGE_NETFILTER
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NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint), &tmp_uint);
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#else
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if (entry->info->pf == PF_BRIDGE) {
|
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/* Case 1: outdev is physical output device, we need to
|
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* look for bridge group (when called from
|
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* netfilter_bridge) */
|
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NFA_PUT(skb, NFQA_IFINDEX_PHYSOUTDEV, sizeof(tmp_uint),
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&tmp_uint);
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/* this is the bridge group "brX" */
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tmp_uint = htonl(entry->info->outdev->br_port->br->dev->ifindex);
|
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NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint),
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&tmp_uint);
|
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} else {
|
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/* Case 2: outdev is bridge group, we need to look for
|
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* physical output device (when called from ipv4) */
|
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NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint),
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&tmp_uint);
|
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if (entry->skb->nf_bridge
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&& entry->skb->nf_bridge->physoutdev) {
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tmp_uint = htonl(entry->skb->nf_bridge->physoutdev->ifindex);
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NFA_PUT(skb, NFQA_IFINDEX_PHYSOUTDEV,
|
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sizeof(tmp_uint), &tmp_uint);
|
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}
|
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}
|
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#endif
|
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}
|
|
|
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if (entry->skb->nfmark) {
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tmp_uint = htonl(entry->skb->nfmark);
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NFA_PUT(skb, NFQA_MARK, sizeof(u_int32_t), &tmp_uint);
|
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}
|
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|
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if (entry->info->indev && entry->skb->dev
|
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&& entry->skb->dev->hard_header_parse) {
|
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struct nfqnl_msg_packet_hw phw;
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|
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phw.hw_addrlen =
|
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entry->skb->dev->hard_header_parse(entry->skb,
|
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phw.hw_addr);
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phw.hw_addrlen = htons(phw.hw_addrlen);
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NFA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
|
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}
|
|
|
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if (entry->skb->stamp.tv_sec) {
|
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struct nfqnl_msg_packet_timestamp ts;
|
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|
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ts.sec = htonll(entry->skb->stamp.tv_sec);
|
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ts.usec = htonll(entry->skb->stamp.tv_usec);
|
|
|
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NFA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts);
|
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}
|
|
|
|
if (data_len) {
|
|
struct nfattr *nfa;
|
|
int size = NFA_LENGTH(data_len);
|
|
|
|
if (skb_tailroom(skb) < (int)NFA_SPACE(data_len)) {
|
|
printk(KERN_WARNING "nf_queue: no tailroom!\n");
|
|
goto nlmsg_failure;
|
|
}
|
|
|
|
nfa = (struct nfattr *)skb_put(skb, NFA_ALIGN(size));
|
|
nfa->nfa_type = NFQA_PAYLOAD;
|
|
nfa->nfa_len = size;
|
|
|
|
if (skb_copy_bits(entry->skb, 0, NFA_DATA(nfa), data_len))
|
|
BUG();
|
|
}
|
|
|
|
nlh->nlmsg_len = skb->tail - old_tail;
|
|
return skb;
|
|
|
|
nlmsg_failure:
|
|
nfattr_failure:
|
|
if (skb)
|
|
kfree_skb(skb);
|
|
*errp = -EINVAL;
|
|
if (net_ratelimit())
|
|
printk(KERN_ERR "nf_queue: error creating packet message\n");
|
|
return NULL;
|
|
}
|
|
|
|
static int
|
|
nfqnl_enqueue_packet(struct sk_buff *skb, struct nf_info *info,
|
|
unsigned int queuenum, void *data)
|
|
{
|
|
int status = -EINVAL;
|
|
struct sk_buff *nskb;
|
|
struct nfqnl_instance *queue;
|
|
struct nfqnl_queue_entry *entry;
|
|
|
|
QDEBUG("entered\n");
|
|
|
|
queue = instance_lookup_get(queuenum);
|
|
if (!queue) {
|
|
QDEBUG("no queue instance matching\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (queue->copy_mode == NFQNL_COPY_NONE) {
|
|
QDEBUG("mode COPY_NONE, aborting\n");
|
|
status = -EAGAIN;
|
|
goto err_out_put;
|
|
}
|
|
|
|
entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
|
|
if (entry == NULL) {
|
|
if (net_ratelimit())
|
|
printk(KERN_ERR
|
|
"nf_queue: OOM in nfqnl_enqueue_packet()\n");
|
|
status = -ENOMEM;
|
|
goto err_out_put;
|
|
}
|
|
|
|
entry->info = info;
|
|
entry->skb = skb;
|
|
entry->id = atomic_inc_return(&queue->id_sequence);
|
|
|
|
nskb = nfqnl_build_packet_message(queue, entry, &status);
|
|
if (nskb == NULL)
|
|
goto err_out_free;
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
if (!queue->peer_pid)
|
|
goto err_out_free_nskb;
|
|
|
|
if (queue->queue_total >= queue->queue_maxlen) {
|
|
queue->queue_dropped++;
|
|
status = -ENOSPC;
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING "ip_queue: full at %d entries, "
|
|
"dropping packets(s). Dropped: %d\n",
|
|
queue->queue_total, queue->queue_dropped);
|
|
goto err_out_free_nskb;
|
|
}
|
|
|
|
/* nfnetlink_unicast will either free the nskb or add it to a socket */
|
|
status = nfnetlink_unicast(nskb, queue->peer_pid, MSG_DONTWAIT);
|
|
if (status < 0) {
|
|
queue->queue_user_dropped++;
|
|
goto err_out_unlock;
|
|
}
|
|
|
|
__enqueue_entry(queue, entry);
|
|
|
|
spin_unlock_bh(&queue->lock);
|
|
instance_put(queue);
|
|
return status;
|
|
|
|
err_out_free_nskb:
|
|
kfree_skb(nskb);
|
|
|
|
err_out_unlock:
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
err_out_free:
|
|
kfree(entry);
|
|
err_out_put:
|
|
instance_put(queue);
|
|
return status;
|
|
}
|
|
|
|
static int
|
|
nfqnl_mangle(void *data, int data_len, struct nfqnl_queue_entry *e)
|
|
{
|
|
int diff;
|
|
|
|
diff = data_len - e->skb->len;
|
|
if (diff < 0)
|
|
skb_trim(e->skb, data_len);
|
|
else if (diff > 0) {
|
|
if (data_len > 0xFFFF)
|
|
return -EINVAL;
|
|
if (diff > skb_tailroom(e->skb)) {
|
|
struct sk_buff *newskb;
|
|
|
|
newskb = skb_copy_expand(e->skb,
|
|
skb_headroom(e->skb),
|
|
diff,
|
|
GFP_ATOMIC);
|
|
if (newskb == NULL) {
|
|
printk(KERN_WARNING "ip_queue: OOM "
|
|
"in mangle, dropping packet\n");
|
|
return -ENOMEM;
|
|
}
|
|
if (e->skb->sk)
|
|
skb_set_owner_w(newskb, e->skb->sk);
|
|
kfree_skb(e->skb);
|
|
e->skb = newskb;
|
|
}
|
|
skb_put(e->skb, diff);
|
|
}
|
|
if (!skb_make_writable(&e->skb, data_len))
|
|
return -ENOMEM;
|
|
memcpy(e->skb->data, data, data_len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int
|
|
id_cmp(struct nfqnl_queue_entry *e, unsigned long id)
|
|
{
|
|
return (id == e->id);
|
|
}
|
|
|
|
static int
|
|
nfqnl_set_mode(struct nfqnl_instance *queue,
|
|
unsigned char mode, unsigned int range)
|
|
{
|
|
int status;
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
status = __nfqnl_set_mode(queue, mode, range);
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
return status;
|
|
}
|
|
|
|
static int
|
|
dev_cmp(struct nfqnl_queue_entry *entry, unsigned long ifindex)
|
|
{
|
|
if (entry->info->indev)
|
|
if (entry->info->indev->ifindex == ifindex)
|
|
return 1;
|
|
|
|
if (entry->info->outdev)
|
|
if (entry->info->outdev->ifindex == ifindex)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* drop all packets with either indev or outdev == ifindex from all queue
|
|
* instances */
|
|
static void
|
|
nfqnl_dev_drop(int ifindex)
|
|
{
|
|
int i;
|
|
|
|
QDEBUG("entering for ifindex %u\n", ifindex);
|
|
|
|
/* this only looks like we have to hold the readlock for a way too long
|
|
* time, issue_verdict(), nf_reinject(), ... - but we always only
|
|
* issue NF_DROP, which is processed directly in nf_reinject() */
|
|
read_lock_bh(&instances_lock);
|
|
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++) {
|
|
struct hlist_node *tmp;
|
|
struct nfqnl_instance *inst;
|
|
struct hlist_head *head = &instance_table[i];
|
|
|
|
hlist_for_each_entry(inst, tmp, head, hlist) {
|
|
struct nfqnl_queue_entry *entry;
|
|
while ((entry = find_dequeue_entry(inst, dev_cmp,
|
|
ifindex)) != NULL)
|
|
issue_verdict(entry, NF_DROP);
|
|
}
|
|
}
|
|
|
|
read_unlock_bh(&instances_lock);
|
|
}
|
|
|
|
#define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
|
|
|
|
static int
|
|
nfqnl_rcv_dev_event(struct notifier_block *this,
|
|
unsigned long event, void *ptr)
|
|
{
|
|
struct net_device *dev = ptr;
|
|
|
|
/* Drop any packets associated with the downed device */
|
|
if (event == NETDEV_DOWN)
|
|
nfqnl_dev_drop(dev->ifindex);
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block nfqnl_dev_notifier = {
|
|
.notifier_call = nfqnl_rcv_dev_event,
|
|
};
|
|
|
|
static int
|
|
nfqnl_rcv_nl_event(struct notifier_block *this,
|
|
unsigned long event, void *ptr)
|
|
{
|
|
struct netlink_notify *n = ptr;
|
|
|
|
if (event == NETLINK_URELEASE &&
|
|
n->protocol == NETLINK_NETFILTER && n->pid) {
|
|
int i;
|
|
|
|
/* destroy all instances for this pid */
|
|
write_lock_bh(&instances_lock);
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++) {
|
|
struct hlist_node *tmp, *t2;
|
|
struct nfqnl_instance *inst;
|
|
struct hlist_head *head = &instance_table[i];
|
|
|
|
hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
|
|
if (n->pid == inst->peer_pid)
|
|
__instance_destroy(inst);
|
|
}
|
|
}
|
|
write_unlock_bh(&instances_lock);
|
|
}
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block nfqnl_rtnl_notifier = {
|
|
.notifier_call = nfqnl_rcv_nl_event,
|
|
};
|
|
|
|
static const int nfqa_verdict_min[NFQA_MAX] = {
|
|
[NFQA_VERDICT_HDR-1] = sizeof(struct nfqnl_msg_verdict_hdr),
|
|
[NFQA_MARK-1] = sizeof(u_int32_t),
|
|
[NFQA_PAYLOAD-1] = 0,
|
|
};
|
|
|
|
static int
|
|
nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
|
|
struct nlmsghdr *nlh, struct nfattr *nfqa[], int *errp)
|
|
{
|
|
struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
|
|
u_int16_t queue_num = ntohs(nfmsg->res_id);
|
|
|
|
struct nfqnl_msg_verdict_hdr *vhdr;
|
|
struct nfqnl_instance *queue;
|
|
unsigned int verdict;
|
|
struct nfqnl_queue_entry *entry;
|
|
int err;
|
|
|
|
if (nfattr_bad_size(nfqa, NFQA_MAX, nfqa_verdict_min)) {
|
|
QDEBUG("bad attribute size\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
queue = instance_lookup_get(queue_num);
|
|
if (!queue)
|
|
return -ENODEV;
|
|
|
|
if (queue->peer_pid != NETLINK_CB(skb).pid) {
|
|
err = -EPERM;
|
|
goto err_out_put;
|
|
}
|
|
|
|
if (!nfqa[NFQA_VERDICT_HDR-1]) {
|
|
err = -EINVAL;
|
|
goto err_out_put;
|
|
}
|
|
|
|
vhdr = NFA_DATA(nfqa[NFQA_VERDICT_HDR-1]);
|
|
verdict = ntohl(vhdr->verdict);
|
|
|
|
if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT) {
|
|
err = -EINVAL;
|
|
goto err_out_put;
|
|
}
|
|
|
|
entry = find_dequeue_entry(queue, id_cmp, ntohl(vhdr->id));
|
|
if (entry == NULL) {
|
|
err = -ENOENT;
|
|
goto err_out_put;
|
|
}
|
|
|
|
if (nfqa[NFQA_PAYLOAD-1]) {
|
|
if (nfqnl_mangle(NFA_DATA(nfqa[NFQA_PAYLOAD-1]),
|
|
NFA_PAYLOAD(nfqa[NFQA_PAYLOAD-1]), entry) < 0)
|
|
verdict = NF_DROP;
|
|
}
|
|
|
|
if (nfqa[NFQA_MARK-1])
|
|
skb->nfmark = ntohl(*(u_int32_t *)NFA_DATA(nfqa[NFQA_MARK-1]));
|
|
|
|
issue_verdict(entry, verdict);
|
|
instance_put(queue);
|
|
return 0;
|
|
|
|
err_out_put:
|
|
instance_put(queue);
|
|
return err;
|
|
}
|
|
|
|
static int
|
|
nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
|
|
struct nlmsghdr *nlh, struct nfattr *nfqa[], int *errp)
|
|
{
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
static const int nfqa_cfg_min[NFQA_CFG_MAX] = {
|
|
[NFQA_CFG_CMD-1] = sizeof(struct nfqnl_msg_config_cmd),
|
|
[NFQA_CFG_PARAMS-1] = sizeof(struct nfqnl_msg_config_params),
|
|
};
|
|
|
|
static struct nf_queue_handler nfqh = {
|
|
.name = "nf_queue",
|
|
.outfn = &nfqnl_enqueue_packet,
|
|
};
|
|
|
|
static int
|
|
nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
|
|
struct nlmsghdr *nlh, struct nfattr *nfqa[], int *errp)
|
|
{
|
|
struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
|
|
u_int16_t queue_num = ntohs(nfmsg->res_id);
|
|
struct nfqnl_instance *queue;
|
|
int ret = 0;
|
|
|
|
QDEBUG("entering for msg %u\n", NFNL_MSG_TYPE(nlh->nlmsg_type));
|
|
|
|
if (nfattr_bad_size(nfqa, NFQA_CFG_MAX, nfqa_cfg_min)) {
|
|
QDEBUG("bad attribute size\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
queue = instance_lookup_get(queue_num);
|
|
if (nfqa[NFQA_CFG_CMD-1]) {
|
|
struct nfqnl_msg_config_cmd *cmd;
|
|
cmd = NFA_DATA(nfqa[NFQA_CFG_CMD-1]);
|
|
QDEBUG("found CFG_CMD\n");
|
|
|
|
switch (cmd->command) {
|
|
case NFQNL_CFG_CMD_BIND:
|
|
if (queue)
|
|
return -EBUSY;
|
|
|
|
queue = instance_create(queue_num, NETLINK_CB(skb).pid);
|
|
if (!queue)
|
|
return -EINVAL;
|
|
break;
|
|
case NFQNL_CFG_CMD_UNBIND:
|
|
if (!queue)
|
|
return -ENODEV;
|
|
|
|
if (queue->peer_pid != NETLINK_CB(skb).pid) {
|
|
ret = -EPERM;
|
|
goto out_put;
|
|
}
|
|
|
|
instance_destroy(queue);
|
|
break;
|
|
case NFQNL_CFG_CMD_PF_BIND:
|
|
QDEBUG("registering queue handler for pf=%u\n",
|
|
ntohs(cmd->pf));
|
|
ret = nf_register_queue_handler(ntohs(cmd->pf), &nfqh);
|
|
break;
|
|
case NFQNL_CFG_CMD_PF_UNBIND:
|
|
QDEBUG("unregistering queue handler for pf=%u\n",
|
|
ntohs(cmd->pf));
|
|
/* This is a bug and a feature. We can unregister
|
|
* other handlers(!) */
|
|
ret = nf_unregister_queue_handler(ntohs(cmd->pf));
|
|
break;
|
|
default:
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
} else {
|
|
if (!queue) {
|
|
QDEBUG("no config command, and no instance ENOENT\n");
|
|
ret = -ENOENT;
|
|
goto out_put;
|
|
}
|
|
|
|
if (queue->peer_pid != NETLINK_CB(skb).pid) {
|
|
QDEBUG("no config command, and wrong pid\n");
|
|
ret = -EPERM;
|
|
goto out_put;
|
|
}
|
|
}
|
|
|
|
if (nfqa[NFQA_CFG_PARAMS-1]) {
|
|
struct nfqnl_msg_config_params *params;
|
|
params = NFA_DATA(nfqa[NFQA_CFG_PARAMS-1]);
|
|
|
|
nfqnl_set_mode(queue, params->copy_mode,
|
|
ntohl(params->copy_range));
|
|
}
|
|
|
|
out_put:
|
|
instance_put(queue);
|
|
return ret;
|
|
}
|
|
|
|
static struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
|
|
[NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp,
|
|
.attr_count = NFQA_MAX,
|
|
.cap_required = CAP_NET_ADMIN },
|
|
[NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict,
|
|
.attr_count = NFQA_MAX,
|
|
.cap_required = CAP_NET_ADMIN },
|
|
[NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
|
|
.attr_count = NFQA_CFG_MAX,
|
|
.cap_required = CAP_NET_ADMIN },
|
|
};
|
|
|
|
static struct nfnetlink_subsystem nfqnl_subsys = {
|
|
.name = "nf_queue",
|
|
.subsys_id = NFNL_SUBSYS_QUEUE,
|
|
.cb_count = NFQNL_MSG_MAX,
|
|
.cb = nfqnl_cb,
|
|
};
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
struct iter_state {
|
|
unsigned int bucket;
|
|
};
|
|
|
|
static struct hlist_node *get_first(struct seq_file *seq)
|
|
{
|
|
struct iter_state *st = seq->private;
|
|
|
|
if (!st)
|
|
return NULL;
|
|
|
|
for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
|
|
if (!hlist_empty(&instance_table[st->bucket]))
|
|
return instance_table[st->bucket].first;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
|
|
{
|
|
struct iter_state *st = seq->private;
|
|
|
|
h = h->next;
|
|
while (!h) {
|
|
if (++st->bucket >= INSTANCE_BUCKETS)
|
|
return NULL;
|
|
|
|
h = instance_table[st->bucket].first;
|
|
}
|
|
return h;
|
|
}
|
|
|
|
static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
|
|
{
|
|
struct hlist_node *head;
|
|
head = get_first(seq);
|
|
|
|
if (head)
|
|
while (pos && (head = get_next(seq, head)))
|
|
pos--;
|
|
return pos ? NULL : head;
|
|
}
|
|
|
|
static void *seq_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
read_lock_bh(&instances_lock);
|
|
return get_idx(seq, *pos);
|
|
}
|
|
|
|
static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
|
|
{
|
|
(*pos)++;
|
|
return get_next(s, v);
|
|
}
|
|
|
|
static void seq_stop(struct seq_file *s, void *v)
|
|
{
|
|
read_unlock_bh(&instances_lock);
|
|
}
|
|
|
|
static int seq_show(struct seq_file *s, void *v)
|
|
{
|
|
const struct nfqnl_instance *inst = v;
|
|
|
|
return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
|
|
inst->queue_num,
|
|
inst->peer_pid, inst->queue_total,
|
|
inst->copy_mode, inst->copy_range,
|
|
inst->queue_dropped, inst->queue_user_dropped,
|
|
atomic_read(&inst->id_sequence),
|
|
atomic_read(&inst->use));
|
|
}
|
|
|
|
static struct seq_operations nfqnl_seq_ops = {
|
|
.start = seq_start,
|
|
.next = seq_next,
|
|
.stop = seq_stop,
|
|
.show = seq_show,
|
|
};
|
|
|
|
static int nfqnl_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct seq_file *seq;
|
|
struct iter_state *is;
|
|
int ret;
|
|
|
|
is = kmalloc(sizeof(*is), GFP_KERNEL);
|
|
if (!is)
|
|
return -ENOMEM;
|
|
memset(is, 0, sizeof(*is));
|
|
ret = seq_open(file, &nfqnl_seq_ops);
|
|
if (ret < 0)
|
|
goto out_free;
|
|
seq = file->private_data;
|
|
seq->private = is;
|
|
return ret;
|
|
out_free:
|
|
kfree(is);
|
|
return ret;
|
|
}
|
|
|
|
static struct file_operations nfqnl_file_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = nfqnl_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release_private,
|
|
};
|
|
|
|
#endif /* PROC_FS */
|
|
|
|
static int
|
|
init_or_cleanup(int init)
|
|
{
|
|
int i, status = -ENOMEM;
|
|
#ifdef CONFIG_PROC_FS
|
|
struct proc_dir_entry *proc_nfqueue;
|
|
#endif
|
|
|
|
if (!init)
|
|
goto cleanup;
|
|
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++)
|
|
INIT_HLIST_HEAD(&instance_table[i]);
|
|
|
|
netlink_register_notifier(&nfqnl_rtnl_notifier);
|
|
status = nfnetlink_subsys_register(&nfqnl_subsys);
|
|
if (status < 0) {
|
|
printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
|
|
goto cleanup_netlink_notifier;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
proc_nfqueue = create_proc_entry("nfnetlink_queue", 0440,
|
|
proc_net_netfilter);
|
|
if (!proc_nfqueue)
|
|
goto cleanup_subsys;
|
|
proc_nfqueue->proc_fops = &nfqnl_file_ops;
|
|
#endif
|
|
|
|
register_netdevice_notifier(&nfqnl_dev_notifier);
|
|
|
|
return status;
|
|
|
|
cleanup:
|
|
nf_unregister_queue_handlers(&nfqh);
|
|
unregister_netdevice_notifier(&nfqnl_dev_notifier);
|
|
#ifdef CONFIG_PROC_FS
|
|
remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
|
|
cleanup_subsys:
|
|
#endif
|
|
nfnetlink_subsys_unregister(&nfqnl_subsys);
|
|
cleanup_netlink_notifier:
|
|
netlink_unregister_notifier(&nfqnl_rtnl_notifier);
|
|
return status;
|
|
}
|
|
|
|
static int __init init(void)
|
|
{
|
|
|
|
return init_or_cleanup(1);
|
|
}
|
|
|
|
static void __exit fini(void)
|
|
{
|
|
init_or_cleanup(0);
|
|
}
|
|
|
|
MODULE_DESCRIPTION("netfilter packet queue handler");
|
|
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
|
|
|
|
module_init(init);
|
|
module_exit(fini);
|