1102 lines
26 KiB
C
1102 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 nfnetlink.
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*
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* (C) 2005 by Harald Welte <laforge@netfilter.org>
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* (C) 2007 by Patrick McHardy <kaber@trash.net>
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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/slab.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 <net/netfilter/nf_queue.h>
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#include <net/netfilter/nfnetlink_queue.h>
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#include <linux/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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struct nfqnl_instance {
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struct hlist_node hlist; /* global list of queues */
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struct rcu_head rcu;
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int peer_portid;
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unsigned int queue_maxlen;
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unsigned int copy_range;
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unsigned int queue_dropped;
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unsigned int queue_user_dropped;
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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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u_int32_t flags; /* Set using NFQA_CFG_FLAGS */
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/*
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* Following fields are dirtied for each queued packet,
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* keep them in same cache line if possible.
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*/
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spinlock_t lock;
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unsigned int queue_total;
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unsigned int id_sequence; /* 'sequence' of pkt ids */
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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 nf_queue_entry *, unsigned long);
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static DEFINE_SPINLOCK(instances_lock);
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#define INSTANCE_BUCKETS 16
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static struct hlist_head instance_table[INSTANCE_BUCKETS] __read_mostly;
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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 nfqnl_instance *inst;
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head = &instance_table[instance_hashfn(queue_num)];
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hlist_for_each_entry_rcu(inst, 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_create(u_int16_t queue_num, int portid)
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{
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struct nfqnl_instance *inst;
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unsigned int h;
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int err;
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spin_lock(&instances_lock);
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if (instance_lookup(queue_num)) {
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err = -EEXIST;
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goto out_unlock;
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}
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inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
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if (!inst) {
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err = -ENOMEM;
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goto out_unlock;
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}
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inst->queue_num = queue_num;
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inst->peer_portid = portid;
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inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
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inst->copy_range = 0xffff;
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inst->copy_mode = NFQNL_COPY_NONE;
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spin_lock_init(&inst->lock);
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INIT_LIST_HEAD(&inst->queue_list);
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if (!try_module_get(THIS_MODULE)) {
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err = -EAGAIN;
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goto out_free;
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}
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h = instance_hashfn(queue_num);
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hlist_add_head_rcu(&inst->hlist, &instance_table[h]);
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spin_unlock(&instances_lock);
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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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spin_unlock(&instances_lock);
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return ERR_PTR(err);
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}
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static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
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unsigned long data);
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static void
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instance_destroy_rcu(struct rcu_head *head)
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{
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struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
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rcu);
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nfqnl_flush(inst, NULL, 0);
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kfree(inst);
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module_put(THIS_MODULE);
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}
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static void
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__instance_destroy(struct nfqnl_instance *inst)
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{
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hlist_del_rcu(&inst->hlist);
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call_rcu(&inst->rcu, instance_destroy_rcu);
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}
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static void
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instance_destroy(struct nfqnl_instance *inst)
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{
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spin_lock(&instances_lock);
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__instance_destroy(inst);
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spin_unlock(&instances_lock);
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}
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static inline void
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__enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
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{
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list_add_tail(&entry->list, &queue->queue_list);
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queue->queue_total++;
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}
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static void
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__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
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{
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list_del(&entry->list);
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queue->queue_total--;
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}
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static struct nf_queue_entry *
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find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
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{
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struct nf_queue_entry *entry = NULL, *i;
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spin_lock_bh(&queue->lock);
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list_for_each_entry(i, &queue->queue_list, list) {
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if (i->id == id) {
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entry = i;
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break;
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}
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}
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if (entry)
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__dequeue_entry(queue, entry);
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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, nfqnl_cmpfn cmpfn, unsigned long data)
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{
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struct nf_queue_entry *entry, *next;
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spin_lock_bh(&queue->lock);
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list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
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if (!cmpfn || cmpfn(entry, data)) {
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list_del(&entry->list);
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queue->queue_total--;
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nf_reinject(entry, NF_DROP);
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}
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}
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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 nf_queue_entry *entry,
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__be32 **packet_id_ptr)
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{
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sk_buff_data_t old_tail;
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size_t size;
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size_t data_len = 0, cap_len = 0;
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struct sk_buff *skb;
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struct nlattr *nla;
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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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struct sk_buff *entskb = entry->skb;
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struct net_device *indev;
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struct net_device *outdev;
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struct nf_conn *ct = NULL;
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enum ip_conntrack_info uninitialized_var(ctinfo);
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size = NLMSG_SPACE(sizeof(struct nfgenmsg))
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+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
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+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
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+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
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#ifdef CONFIG_BRIDGE_NETFILTER
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+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
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+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
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#endif
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+ nla_total_size(sizeof(u_int32_t)) /* mark */
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+ nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
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+ nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp)
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+ nla_total_size(sizeof(u_int32_t))); /* cap_len */
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outdev = entry->outdev;
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switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
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case NFQNL_COPY_META:
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case NFQNL_COPY_NONE:
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break;
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case NFQNL_COPY_PACKET:
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if (entskb->ip_summed == CHECKSUM_PARTIAL &&
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skb_checksum_help(entskb))
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return NULL;
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data_len = ACCESS_ONCE(queue->copy_range);
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if (data_len == 0 || data_len > entskb->len)
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data_len = entskb->len;
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size += nla_total_size(data_len);
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cap_len = entskb->len;
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break;
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}
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if (queue->flags & NFQA_CFG_F_CONNTRACK)
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ct = nfqnl_ct_get(entskb, &size, &ctinfo);
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skb = alloc_skb(size, GFP_ATOMIC);
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if (!skb)
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return NULL;
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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), 0);
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if (!nlh) {
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kfree_skb(skb);
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return NULL;
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}
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nfmsg = nlmsg_data(nlh);
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nfmsg->nfgen_family = entry->pf;
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nfmsg->version = NFNETLINK_V0;
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nfmsg->res_id = htons(queue->queue_num);
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nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
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pmsg = nla_data(nla);
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pmsg->hw_protocol = entskb->protocol;
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pmsg->hook = entry->hook;
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*packet_id_ptr = &pmsg->packet_id;
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indev = entry->indev;
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if (indev) {
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#ifndef CONFIG_BRIDGE_NETFILTER
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if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
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goto nla_put_failure;
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#else
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if (entry->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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if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
|
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htonl(indev->ifindex)) ||
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/* this is the bridge group "brX" */
|
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/* rcu_read_lock()ed by __nf_queue */
|
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nla_put_be32(skb, NFQA_IFINDEX_INDEV,
|
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htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
|
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goto nla_put_failure;
|
|
} else {
|
|
/* Case 2: indev is bridge group, we need to look for
|
|
* physical device (when called from ipv4) */
|
|
if (nla_put_be32(skb, NFQA_IFINDEX_INDEV,
|
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htonl(indev->ifindex)))
|
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goto nla_put_failure;
|
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if (entskb->nf_bridge && entskb->nf_bridge->physindev &&
|
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nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
|
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htonl(entskb->nf_bridge->physindev->ifindex)))
|
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goto nla_put_failure;
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}
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#endif
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}
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|
|
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if (outdev) {
|
|
#ifndef CONFIG_BRIDGE_NETFILTER
|
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if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
|
|
goto nla_put_failure;
|
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#else
|
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if (entry->pf == PF_BRIDGE) {
|
|
/* Case 1: outdev is physical output device, we need to
|
|
* look for bridge group (when called from
|
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* netfilter_bridge) */
|
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if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
|
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htonl(outdev->ifindex)) ||
|
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/* this is the bridge group "brX" */
|
|
/* rcu_read_lock()ed by __nf_queue */
|
|
nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
|
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htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
|
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goto nla_put_failure;
|
|
} else {
|
|
/* Case 2: outdev is bridge group, we need to look for
|
|
* physical output device (when called from ipv4) */
|
|
if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
|
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htonl(outdev->ifindex)))
|
|
goto nla_put_failure;
|
|
if (entskb->nf_bridge && entskb->nf_bridge->physoutdev &&
|
|
nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
|
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htonl(entskb->nf_bridge->physoutdev->ifindex)))
|
|
goto nla_put_failure;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
if (entskb->mark &&
|
|
nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark)))
|
|
goto nla_put_failure;
|
|
|
|
if (indev && entskb->dev &&
|
|
entskb->mac_header != entskb->network_header) {
|
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struct nfqnl_msg_packet_hw phw;
|
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int len = dev_parse_header(entskb, phw.hw_addr);
|
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if (len) {
|
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phw.hw_addrlen = htons(len);
|
|
if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
|
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goto nla_put_failure;
|
|
}
|
|
}
|
|
|
|
if (entskb->tstamp.tv64) {
|
|
struct nfqnl_msg_packet_timestamp ts;
|
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struct timeval tv = ktime_to_timeval(entskb->tstamp);
|
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ts.sec = cpu_to_be64(tv.tv_sec);
|
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ts.usec = cpu_to_be64(tv.tv_usec);
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|
|
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if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
|
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goto nla_put_failure;
|
|
}
|
|
|
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if (data_len) {
|
|
struct nlattr *nla;
|
|
int sz = nla_attr_size(data_len);
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|
|
|
if (skb_tailroom(skb) < nla_total_size(data_len)) {
|
|
printk(KERN_WARNING "nf_queue: no tailroom!\n");
|
|
kfree_skb(skb);
|
|
return NULL;
|
|
}
|
|
|
|
nla = (struct nlattr *)skb_put(skb, nla_total_size(data_len));
|
|
nla->nla_type = NFQA_PAYLOAD;
|
|
nla->nla_len = sz;
|
|
|
|
if (skb_copy_bits(entskb, 0, nla_data(nla), data_len))
|
|
BUG();
|
|
}
|
|
|
|
if (ct && nfqnl_ct_put(skb, ct, ctinfo) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (cap_len > 0 && nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
|
|
goto nla_put_failure;
|
|
|
|
nlh->nlmsg_len = skb->tail - old_tail;
|
|
return skb;
|
|
|
|
nla_put_failure:
|
|
kfree_skb(skb);
|
|
net_err_ratelimited("nf_queue: error creating packet message\n");
|
|
return NULL;
|
|
}
|
|
|
|
static int
|
|
nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
|
|
{
|
|
struct sk_buff *nskb;
|
|
struct nfqnl_instance *queue;
|
|
int err = -ENOBUFS;
|
|
__be32 *packet_id_ptr;
|
|
int failopen = 0;
|
|
|
|
/* rcu_read_lock()ed by nf_hook_slow() */
|
|
queue = instance_lookup(queuenum);
|
|
if (!queue) {
|
|
err = -ESRCH;
|
|
goto err_out;
|
|
}
|
|
|
|
if (queue->copy_mode == NFQNL_COPY_NONE) {
|
|
err = -EINVAL;
|
|
goto err_out;
|
|
}
|
|
|
|
nskb = nfqnl_build_packet_message(queue, entry, &packet_id_ptr);
|
|
if (nskb == NULL) {
|
|
err = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
if (!queue->peer_portid) {
|
|
err = -EINVAL;
|
|
goto err_out_free_nskb;
|
|
}
|
|
if (queue->queue_total >= queue->queue_maxlen) {
|
|
if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
|
|
failopen = 1;
|
|
err = 0;
|
|
} else {
|
|
queue->queue_dropped++;
|
|
net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n",
|
|
queue->queue_total);
|
|
}
|
|
goto err_out_free_nskb;
|
|
}
|
|
entry->id = ++queue->id_sequence;
|
|
*packet_id_ptr = htonl(entry->id);
|
|
|
|
/* nfnetlink_unicast will either free the nskb or add it to a socket */
|
|
err = nfnetlink_unicast(nskb, &init_net, queue->peer_portid, MSG_DONTWAIT);
|
|
if (err < 0) {
|
|
queue->queue_user_dropped++;
|
|
goto err_out_unlock;
|
|
}
|
|
|
|
__enqueue_entry(queue, entry);
|
|
|
|
spin_unlock_bh(&queue->lock);
|
|
return 0;
|
|
|
|
err_out_free_nskb:
|
|
kfree_skb(nskb);
|
|
err_out_unlock:
|
|
spin_unlock_bh(&queue->lock);
|
|
if (failopen)
|
|
nf_reinject(entry, NF_ACCEPT);
|
|
err_out:
|
|
return err;
|
|
}
|
|
|
|
static int
|
|
nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff)
|
|
{
|
|
struct sk_buff *nskb;
|
|
|
|
if (diff < 0) {
|
|
if (pskb_trim(e->skb, data_len))
|
|
return -ENOMEM;
|
|
} else if (diff > 0) {
|
|
if (data_len > 0xFFFF)
|
|
return -EINVAL;
|
|
if (diff > skb_tailroom(e->skb)) {
|
|
nskb = skb_copy_expand(e->skb, skb_headroom(e->skb),
|
|
diff, GFP_ATOMIC);
|
|
if (!nskb) {
|
|
printk(KERN_WARNING "nf_queue: OOM "
|
|
"in mangle, dropping packet\n");
|
|
return -ENOMEM;
|
|
}
|
|
kfree_skb(e->skb);
|
|
e->skb = nskb;
|
|
}
|
|
skb_put(e->skb, diff);
|
|
}
|
|
if (!skb_make_writable(e->skb, data_len))
|
|
return -ENOMEM;
|
|
skb_copy_to_linear_data(e->skb, data, data_len);
|
|
e->skb->ip_summed = CHECKSUM_NONE;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
nfqnl_set_mode(struct nfqnl_instance *queue,
|
|
unsigned char mode, unsigned int range)
|
|
{
|
|
int status = 0;
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
switch (mode) {
|
|
case NFQNL_COPY_NONE:
|
|
case NFQNL_COPY_META:
|
|
queue->copy_mode = mode;
|
|
queue->copy_range = 0;
|
|
break;
|
|
|
|
case NFQNL_COPY_PACKET:
|
|
queue->copy_mode = mode;
|
|
/* We're using struct nlattr which has 16bit nla_len. Note that
|
|
* nla_len includes the header length. Thus, the maximum packet
|
|
* length that we support is 65531 bytes. We send truncated
|
|
* packets if the specified length is larger than that.
|
|
*/
|
|
if (range > 0xffff - NLA_HDRLEN)
|
|
queue->copy_range = 0xffff - NLA_HDRLEN;
|
|
else
|
|
queue->copy_range = range;
|
|
break;
|
|
|
|
default:
|
|
status = -EINVAL;
|
|
|
|
}
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
return status;
|
|
}
|
|
|
|
static int
|
|
dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex)
|
|
{
|
|
if (entry->indev)
|
|
if (entry->indev->ifindex == ifindex)
|
|
return 1;
|
|
if (entry->outdev)
|
|
if (entry->outdev->ifindex == ifindex)
|
|
return 1;
|
|
#ifdef CONFIG_BRIDGE_NETFILTER
|
|
if (entry->skb->nf_bridge) {
|
|
if (entry->skb->nf_bridge->physindev &&
|
|
entry->skb->nf_bridge->physindev->ifindex == ifindex)
|
|
return 1;
|
|
if (entry->skb->nf_bridge->physoutdev &&
|
|
entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
|
|
return 1;
|
|
}
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
/* drop all packets with either indev or outdev == ifindex from all queue
|
|
* instances */
|
|
static void
|
|
nfqnl_dev_drop(int ifindex)
|
|
{
|
|
int i;
|
|
|
|
rcu_read_lock();
|
|
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++) {
|
|
struct nfqnl_instance *inst;
|
|
struct hlist_head *head = &instance_table[i];
|
|
|
|
hlist_for_each_entry_rcu(inst, head, hlist)
|
|
nfqnl_flush(inst, dev_cmp, ifindex);
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
#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;
|
|
|
|
if (!net_eq(dev_net(dev), &init_net))
|
|
return NOTIFY_DONE;
|
|
|
|
/* 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) {
|
|
int i;
|
|
|
|
/* destroy all instances for this portid */
|
|
spin_lock(&instances_lock);
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++) {
|
|
struct hlist_node *t2;
|
|
struct nfqnl_instance *inst;
|
|
struct hlist_head *head = &instance_table[i];
|
|
|
|
hlist_for_each_entry_safe(inst, t2, head, hlist) {
|
|
if ((n->net == &init_net) &&
|
|
(n->portid == inst->peer_portid))
|
|
__instance_destroy(inst);
|
|
}
|
|
}
|
|
spin_unlock(&instances_lock);
|
|
}
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block nfqnl_rtnl_notifier = {
|
|
.notifier_call = nfqnl_rcv_nl_event,
|
|
};
|
|
|
|
static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = {
|
|
[NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
|
|
[NFQA_MARK] = { .type = NLA_U32 },
|
|
[NFQA_PAYLOAD] = { .type = NLA_UNSPEC },
|
|
[NFQA_CT] = { .type = NLA_UNSPEC },
|
|
};
|
|
|
|
static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = {
|
|
[NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) },
|
|
[NFQA_MARK] = { .type = NLA_U32 },
|
|
};
|
|
|
|
static struct nfqnl_instance *verdict_instance_lookup(u16 queue_num, int nlportid)
|
|
{
|
|
struct nfqnl_instance *queue;
|
|
|
|
queue = instance_lookup(queue_num);
|
|
if (!queue)
|
|
return ERR_PTR(-ENODEV);
|
|
|
|
if (queue->peer_portid != nlportid)
|
|
return ERR_PTR(-EPERM);
|
|
|
|
return queue;
|
|
}
|
|
|
|
static struct nfqnl_msg_verdict_hdr*
|
|
verdicthdr_get(const struct nlattr * const nfqa[])
|
|
{
|
|
struct nfqnl_msg_verdict_hdr *vhdr;
|
|
unsigned int verdict;
|
|
|
|
if (!nfqa[NFQA_VERDICT_HDR])
|
|
return NULL;
|
|
|
|
vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]);
|
|
verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK;
|
|
if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN)
|
|
return NULL;
|
|
return vhdr;
|
|
}
|
|
|
|
static int nfq_id_after(unsigned int id, unsigned int max)
|
|
{
|
|
return (int)(id - max) > 0;
|
|
}
|
|
|
|
static int
|
|
nfqnl_recv_verdict_batch(struct sock *ctnl, struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[])
|
|
{
|
|
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
|
|
struct nf_queue_entry *entry, *tmp;
|
|
unsigned int verdict, maxid;
|
|
struct nfqnl_msg_verdict_hdr *vhdr;
|
|
struct nfqnl_instance *queue;
|
|
LIST_HEAD(batch_list);
|
|
u16 queue_num = ntohs(nfmsg->res_id);
|
|
|
|
queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).portid);
|
|
if (IS_ERR(queue))
|
|
return PTR_ERR(queue);
|
|
|
|
vhdr = verdicthdr_get(nfqa);
|
|
if (!vhdr)
|
|
return -EINVAL;
|
|
|
|
verdict = ntohl(vhdr->verdict);
|
|
maxid = ntohl(vhdr->id);
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) {
|
|
if (nfq_id_after(entry->id, maxid))
|
|
break;
|
|
__dequeue_entry(queue, entry);
|
|
list_add_tail(&entry->list, &batch_list);
|
|
}
|
|
|
|
spin_unlock_bh(&queue->lock);
|
|
|
|
if (list_empty(&batch_list))
|
|
return -ENOENT;
|
|
|
|
list_for_each_entry_safe(entry, tmp, &batch_list, list) {
|
|
if (nfqa[NFQA_MARK])
|
|
entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
|
|
nf_reinject(entry, verdict);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[])
|
|
{
|
|
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 nf_queue_entry *entry;
|
|
enum ip_conntrack_info uninitialized_var(ctinfo);
|
|
struct nf_conn *ct = NULL;
|
|
|
|
queue = instance_lookup(queue_num);
|
|
if (!queue)
|
|
|
|
queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).portid);
|
|
if (IS_ERR(queue))
|
|
return PTR_ERR(queue);
|
|
|
|
vhdr = verdicthdr_get(nfqa);
|
|
if (!vhdr)
|
|
return -EINVAL;
|
|
|
|
verdict = ntohl(vhdr->verdict);
|
|
|
|
entry = find_dequeue_entry(queue, ntohl(vhdr->id));
|
|
if (entry == NULL)
|
|
return -ENOENT;
|
|
|
|
rcu_read_lock();
|
|
if (nfqa[NFQA_CT] && (queue->flags & NFQA_CFG_F_CONNTRACK))
|
|
ct = nfqnl_ct_parse(entry->skb, nfqa[NFQA_CT], &ctinfo);
|
|
|
|
if (nfqa[NFQA_PAYLOAD]) {
|
|
u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]);
|
|
int diff = payload_len - entry->skb->len;
|
|
|
|
if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
|
|
payload_len, entry, diff) < 0)
|
|
verdict = NF_DROP;
|
|
|
|
if (ct)
|
|
nfqnl_ct_seq_adjust(skb, ct, ctinfo, diff);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (nfqa[NFQA_MARK])
|
|
entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
|
|
|
|
nf_reinject(entry, verdict);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[])
|
|
{
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = {
|
|
[NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) },
|
|
[NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) },
|
|
};
|
|
|
|
static const struct nf_queue_handler nfqh = {
|
|
.outfn = &nfqnl_enqueue_packet,
|
|
};
|
|
|
|
static int
|
|
nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[])
|
|
{
|
|
struct nfgenmsg *nfmsg = nlmsg_data(nlh);
|
|
u_int16_t queue_num = ntohs(nfmsg->res_id);
|
|
struct nfqnl_instance *queue;
|
|
struct nfqnl_msg_config_cmd *cmd = NULL;
|
|
int ret = 0;
|
|
|
|
if (nfqa[NFQA_CFG_CMD]) {
|
|
cmd = nla_data(nfqa[NFQA_CFG_CMD]);
|
|
|
|
/* Obsolete commands without queue context */
|
|
switch (cmd->command) {
|
|
case NFQNL_CFG_CMD_PF_BIND: return 0;
|
|
case NFQNL_CFG_CMD_PF_UNBIND: return 0;
|
|
}
|
|
}
|
|
|
|
rcu_read_lock();
|
|
queue = instance_lookup(queue_num);
|
|
if (queue && queue->peer_portid != NETLINK_CB(skb).portid) {
|
|
ret = -EPERM;
|
|
goto err_out_unlock;
|
|
}
|
|
|
|
if (cmd != NULL) {
|
|
switch (cmd->command) {
|
|
case NFQNL_CFG_CMD_BIND:
|
|
if (queue) {
|
|
ret = -EBUSY;
|
|
goto err_out_unlock;
|
|
}
|
|
queue = instance_create(queue_num, NETLINK_CB(skb).portid);
|
|
if (IS_ERR(queue)) {
|
|
ret = PTR_ERR(queue);
|
|
goto err_out_unlock;
|
|
}
|
|
break;
|
|
case NFQNL_CFG_CMD_UNBIND:
|
|
if (!queue) {
|
|
ret = -ENODEV;
|
|
goto err_out_unlock;
|
|
}
|
|
instance_destroy(queue);
|
|
break;
|
|
case NFQNL_CFG_CMD_PF_BIND:
|
|
case NFQNL_CFG_CMD_PF_UNBIND:
|
|
break;
|
|
default:
|
|
ret = -ENOTSUPP;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (nfqa[NFQA_CFG_PARAMS]) {
|
|
struct nfqnl_msg_config_params *params;
|
|
|
|
if (!queue) {
|
|
ret = -ENODEV;
|
|
goto err_out_unlock;
|
|
}
|
|
params = nla_data(nfqa[NFQA_CFG_PARAMS]);
|
|
nfqnl_set_mode(queue, params->copy_mode,
|
|
ntohl(params->copy_range));
|
|
}
|
|
|
|
if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) {
|
|
__be32 *queue_maxlen;
|
|
|
|
if (!queue) {
|
|
ret = -ENODEV;
|
|
goto err_out_unlock;
|
|
}
|
|
queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]);
|
|
spin_lock_bh(&queue->lock);
|
|
queue->queue_maxlen = ntohl(*queue_maxlen);
|
|
spin_unlock_bh(&queue->lock);
|
|
}
|
|
|
|
if (nfqa[NFQA_CFG_FLAGS]) {
|
|
__u32 flags, mask;
|
|
|
|
if (!queue) {
|
|
ret = -ENODEV;
|
|
goto err_out_unlock;
|
|
}
|
|
|
|
if (!nfqa[NFQA_CFG_MASK]) {
|
|
/* A mask is needed to specify which flags are being
|
|
* changed.
|
|
*/
|
|
ret = -EINVAL;
|
|
goto err_out_unlock;
|
|
}
|
|
|
|
flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
|
|
mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
|
|
|
|
if (flags >= NFQA_CFG_F_MAX) {
|
|
ret = -EOPNOTSUPP;
|
|
goto err_out_unlock;
|
|
}
|
|
|
|
spin_lock_bh(&queue->lock);
|
|
queue->flags &= ~mask;
|
|
queue->flags |= flags & mask;
|
|
spin_unlock_bh(&queue->lock);
|
|
}
|
|
|
|
err_out_unlock:
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
|
|
static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
|
|
[NFQNL_MSG_PACKET] = { .call_rcu = nfqnl_recv_unsupp,
|
|
.attr_count = NFQA_MAX, },
|
|
[NFQNL_MSG_VERDICT] = { .call_rcu = nfqnl_recv_verdict,
|
|
.attr_count = NFQA_MAX,
|
|
.policy = nfqa_verdict_policy },
|
|
[NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
|
|
.attr_count = NFQA_CFG_MAX,
|
|
.policy = nfqa_cfg_policy },
|
|
[NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch,
|
|
.attr_count = NFQA_MAX,
|
|
.policy = nfqa_verdict_batch_policy },
|
|
};
|
|
|
|
static const 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)
|
|
__acquires(instances_lock)
|
|
{
|
|
spin_lock(&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)
|
|
__releases(instances_lock)
|
|
{
|
|
spin_unlock(&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_portid, inst->queue_total,
|
|
inst->copy_mode, inst->copy_range,
|
|
inst->queue_dropped, inst->queue_user_dropped,
|
|
inst->id_sequence, 1);
|
|
}
|
|
|
|
static const 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)
|
|
{
|
|
return seq_open_private(file, &nfqnl_seq_ops,
|
|
sizeof(struct iter_state));
|
|
}
|
|
|
|
static const 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 nfnetlink_queue_init(void)
|
|
{
|
|
int i, status = -ENOMEM;
|
|
|
|
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
|
|
if (!proc_create("nfnetlink_queue", 0440,
|
|
proc_net_netfilter, &nfqnl_file_ops))
|
|
goto cleanup_subsys;
|
|
#endif
|
|
|
|
register_netdevice_notifier(&nfqnl_dev_notifier);
|
|
nf_register_queue_handler(&nfqh);
|
|
return status;
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
cleanup_subsys:
|
|
nfnetlink_subsys_unregister(&nfqnl_subsys);
|
|
#endif
|
|
cleanup_netlink_notifier:
|
|
netlink_unregister_notifier(&nfqnl_rtnl_notifier);
|
|
return status;
|
|
}
|
|
|
|
static void __exit nfnetlink_queue_fini(void)
|
|
{
|
|
nf_unregister_queue_handler();
|
|
unregister_netdevice_notifier(&nfqnl_dev_notifier);
|
|
#ifdef CONFIG_PROC_FS
|
|
remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
|
|
#endif
|
|
nfnetlink_subsys_unregister(&nfqnl_subsys);
|
|
netlink_unregister_notifier(&nfqnl_rtnl_notifier);
|
|
|
|
rcu_barrier(); /* Wait for completion of call_rcu()'s */
|
|
}
|
|
|
|
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(nfnetlink_queue_init);
|
|
module_exit(nfnetlink_queue_fini);
|