blob: 4162437b83614e380a70d5f4fe2a94e76a4d0a0d [file] [log] [blame]
/*
* This is a module which is used for queueing packets and communicating with
* userspace via nfnetlink.
*
* (C) 2005 by Harald Welte <laforge@netfilter.org>
* (C) 2007 by Patrick McHardy <kaber@trash.net>
*
* Based on the old ipv4-only ip_queue.c:
* (C) 2000-2002 James Morris <jmorris@intercode.com.au>
* (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <linux/netfilter.h>
#include <linux/proc_fs.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_queue.h>
#include <linux/list.h>
#include <net/sock.h>
#include <net/netfilter/nf_queue.h>
#include <linux/atomic.h>
#ifdef CONFIG_BRIDGE_NETFILTER
#include "../bridge/br_private.h"
#endif
#define NFQNL_QMAX_DEFAULT 1024
struct nfqnl_instance {
struct hlist_node hlist; /* global list of queues */
struct rcu_head rcu;
int peer_pid;
unsigned int queue_maxlen;
unsigned int copy_range;
unsigned int queue_dropped;
unsigned int queue_user_dropped;
u_int16_t queue_num; /* number of this queue */
u_int8_t copy_mode;
/*
* Following fields are dirtied for each queued packet,
* keep them in same cache line if possible.
*/
spinlock_t lock;
unsigned int queue_total;
unsigned int id_sequence; /* 'sequence' of pkt ids */
struct list_head queue_list; /* packets in queue */
};
typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long);
static DEFINE_SPINLOCK(instances_lock);
#define INSTANCE_BUCKETS 16
static struct hlist_head instance_table[INSTANCE_BUCKETS] __read_mostly;
static inline u_int8_t instance_hashfn(u_int16_t queue_num)
{
return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS;
}
static struct nfqnl_instance *
instance_lookup(u_int16_t queue_num)
{
struct hlist_head *head;
struct hlist_node *pos;
struct nfqnl_instance *inst;
head = &instance_table[instance_hashfn(queue_num)];
hlist_for_each_entry_rcu(inst, pos, head, hlist) {
if (inst->queue_num == queue_num)
return inst;
}
return NULL;
}
static struct nfqnl_instance *
instance_create(u_int16_t queue_num, int pid)
{
struct nfqnl_instance *inst;
unsigned int h;
int err;
spin_lock(&instances_lock);
if (instance_lookup(queue_num)) {
err = -EEXIST;
goto out_unlock;
}
inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
if (!inst) {
err = -ENOMEM;
goto out_unlock;
}
inst->queue_num = queue_num;
inst->peer_pid = pid;
inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
inst->copy_range = 0xfffff;
inst->copy_mode = NFQNL_COPY_NONE;
spin_lock_init(&inst->lock);
INIT_LIST_HEAD(&inst->queue_list);
if (!try_module_get(THIS_MODULE)) {
err = -EAGAIN;
goto out_free;
}
h = instance_hashfn(queue_num);
hlist_add_head_rcu(&inst->hlist, &instance_table[h]);
spin_unlock(&instances_lock);
return inst;
out_free:
kfree(inst);
out_unlock:
spin_unlock(&instances_lock);
return ERR_PTR(err);
}
static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
unsigned long data);
static void
instance_destroy_rcu(struct rcu_head *head)
{
struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance,
rcu);
nfqnl_flush(inst, NULL, 0);
kfree(inst);
module_put(THIS_MODULE);
}
static void
__instance_destroy(struct nfqnl_instance *inst)
{
hlist_del_rcu(&inst->hlist);
call_rcu(&inst->rcu, instance_destroy_rcu);
}
static void
instance_destroy(struct nfqnl_instance *inst)
{
spin_lock(&instances_lock);
__instance_destroy(inst);
spin_unlock(&instances_lock);
}
static inline void
__enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
{
list_add_tail(&entry->list, &queue->queue_list);
queue->queue_total++;
}
static void
__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry)
{
list_del(&entry->list);
queue->queue_total--;
}
static struct nf_queue_entry *
find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
{
struct nf_queue_entry *entry = NULL, *i;
spin_lock_bh(&queue->lock);
list_for_each_entry(i, &queue->queue_list, list) {
if (i->id == id) {
entry = i;
break;
}
}
if (entry)
__dequeue_entry(queue, entry);
spin_unlock_bh(&queue->lock);
return entry;
}
static void
nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
{
struct nf_queue_entry *entry, *next;
spin_lock_bh(&queue->lock);
list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
if (!cmpfn || cmpfn(entry, data)) {
list_del(&entry->list);
queue->queue_total--;
nf_reinject(entry, NF_DROP);
}
}
spin_unlock_bh(&queue->lock);
}
static struct sk_buff *
nfqnl_build_packet_message(struct nfqnl_instance *queue,
struct nf_queue_entry *entry,
__be32 **packet_id_ptr)
{
sk_buff_data_t old_tail;
size_t size;
size_t data_len = 0;
struct sk_buff *skb;
struct nlattr *nla;
struct nfqnl_msg_packet_hdr *pmsg;
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
struct sk_buff *entskb = entry->skb;
struct net_device *indev;
struct net_device *outdev;
size = NLMSG_SPACE(sizeof(struct nfgenmsg))
+ nla_total_size(sizeof(struct nfqnl_msg_packet_hdr))
+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
#ifdef CONFIG_BRIDGE_NETFILTER
+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
+ nla_total_size(sizeof(u_int32_t)) /* ifindex */
#endif
+ nla_total_size(sizeof(u_int32_t)) /* mark */
+ nla_total_size(sizeof(struct nfqnl_msg_packet_hw))
+ nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
outdev = entry->outdev;
switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
case NFQNL_COPY_META:
case NFQNL_COPY_NONE:
break;
case NFQNL_COPY_PACKET:
if (entskb->ip_summed == CHECKSUM_PARTIAL &&
skb_checksum_help(entskb))
return NULL;
data_len = ACCESS_ONCE(queue->copy_range);
if (data_len == 0 || data_len > entskb->len)
data_len = entskb->len;
size += nla_total_size(data_len);
break;
}
skb = alloc_skb(size, GFP_ATOMIC);
if (!skb)
goto nlmsg_failure;
old_tail = skb->tail;
nlh = NLMSG_PUT(skb, 0, 0,
NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
sizeof(struct nfgenmsg));
nfmsg = NLMSG_DATA(nlh);
nfmsg->nfgen_family = entry->pf;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = htons(queue->queue_num);
nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg));
pmsg = nla_data(nla);
pmsg->hw_protocol = entskb->protocol;
pmsg->hook = entry->hook;
*packet_id_ptr = &pmsg->packet_id;
indev = entry->indev;
if (indev) {
#ifndef CONFIG_BRIDGE_NETFILTER
if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
goto nla_put_failure;
#else
if (entry->pf == PF_BRIDGE) {
/* Case 1: indev is physical input device, we need to
* look for bridge group (when called from
* netfilter_bridge) */
if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
htonl(indev->ifindex)) ||
/* this is the bridge group "brX" */
/* rcu_read_lock()ed by __nf_queue */
nla_put_be32(skb, NFQA_IFINDEX_INDEV,
htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
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,
htonl(indev->ifindex)))
goto nla_put_failure;
if (entskb->nf_bridge && entskb->nf_bridge->physindev &&
nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
htonl(entskb->nf_bridge->physindev->ifindex)))
goto nla_put_failure;
}
#endif
}
if (outdev) {
#ifndef CONFIG_BRIDGE_NETFILTER
if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
goto nla_put_failure;
#else
if (entry->pf == PF_BRIDGE) {
/* Case 1: outdev is physical output device, we need to
* look for bridge group (when called from
* netfilter_bridge) */
if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
htonl(outdev->ifindex)) ||
/* this is the bridge group "brX" */
/* rcu_read_lock()ed by __nf_queue */
nla_put_be32(skb, NFQA_IFINDEX_OUTDEV,
htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
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,
htonl(outdev->ifindex)))
goto nla_put_failure;
if (entskb->nf_bridge && entskb->nf_bridge->physoutdev &&
nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
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) {
struct nfqnl_msg_packet_hw phw;
int len = dev_parse_header(entskb, phw.hw_addr);
if (len) {
phw.hw_addrlen = htons(len);
if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw))
goto nla_put_failure;
}
}
if (entskb->tstamp.tv64) {
struct nfqnl_msg_packet_timestamp ts;
struct timeval tv = ktime_to_timeval(entskb->tstamp);
ts.sec = cpu_to_be64(tv.tv_sec);
ts.usec = cpu_to_be64(tv.tv_usec);
if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
goto nla_put_failure;
}
if (data_len) {
struct nlattr *nla;
int sz = nla_attr_size(data_len);
if (skb_tailroom(skb) < nla_total_size(data_len)) {
printk(KERN_WARNING "nf_queue: no tailroom!\n");
goto nlmsg_failure;
}
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();
}
nlh->nlmsg_len = skb->tail - old_tail;
return skb;
nlmsg_failure:
nla_put_failure:
if (skb)
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;
/* 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_pid) {
err = -EINVAL;
goto err_out_free_nskb;
}
if (queue->queue_total >= queue->queue_maxlen) {
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_pid, 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);
err_out:
return err;
}
static int
nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e)
{
struct sk_buff *nskb;
int diff;
diff = data_len - e->skb->len;
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 */
if (range > 0xffff)
queue->copy_range = 0xffff;
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 hlist_node *tmp;
struct nfqnl_instance *inst;
struct hlist_head *head = &instance_table[i];
hlist_for_each_entry_rcu(inst, tmp, 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 pid */
spin_lock(&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->net == &init_net) &&
(n->pid == inst->peer_pid))
__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 },
};
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 nlpid)
{
struct nfqnl_instance *queue;
queue = instance_lookup(queue_num);
if (!queue)
return ERR_PTR(-ENODEV);
if (queue->peer_pid != nlpid)
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).pid);
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;
queue = instance_lookup(queue_num);
if (!queue)
queue = verdict_instance_lookup(queue_num, NETLINK_CB(skb).pid);
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;
if (nfqa[NFQA_PAYLOAD]) {
if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]),
nla_len(nfqa[NFQA_PAYLOAD]), entry) < 0)
verdict = NF_DROP;
}
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 = {
.name = "nf_queue",
.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]);
/* Commands without queue context - might sleep */
switch (cmd->command) {
case NFQNL_CFG_CMD_PF_BIND:
return nf_register_queue_handler(ntohs(cmd->pf),
&nfqh);
case NFQNL_CFG_CMD_PF_UNBIND:
return nf_unregister_queue_handler(ntohs(cmd->pf),
&nfqh);
}
}
rcu_read_lock();
queue = instance_lookup(queue_num);
if (queue && queue->peer_pid != NETLINK_CB(skb).pid) {
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).pid);
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);
}
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_pid, 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);
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_handlers(&nfqh);
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);