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nfnetlink_queue.c
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nfnetlink_queue.c
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/*
* This is a module which is used for queueing packets and communicating with
* userspace via nfetlink.
*
* (C) 2005 by Harald Welte <[email protected]>
*
* Based on the old ipv4-only ip_queue.c:
* (C) 2000-2002 James Morris <[email protected]>
* (C) 2003-2005 Netfilter Core Team <[email protected]>
*
* 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/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 <asm/atomic.h>
#ifdef CONFIG_BRIDGE_NETFILTER
#include "../bridge/br_private.h"
#endif
#define NFQNL_QMAX_DEFAULT 1024
#if 0
#define QDEBUG(x, args ...) printk(KERN_DEBUG "%s(%d):%s(): " x, \
__FILE__, __LINE__, __FUNCTION__, \
## args)
#else
#define QDEBUG(x, ...)
#endif
struct nfqnl_queue_entry {
struct list_head list;
struct nf_info *info;
struct sk_buff *skb;
unsigned int id;
};
struct nfqnl_instance {
struct hlist_node hlist; /* global list of queues */
atomic_t use;
int peer_pid;
unsigned int queue_maxlen;
unsigned int copy_range;
unsigned int queue_total;
unsigned int queue_dropped;
unsigned int queue_user_dropped;
atomic_t id_sequence; /* 'sequence' of pkt ids */
u_int16_t queue_num; /* number of this queue */
u_int8_t copy_mode;
spinlock_t lock;
struct list_head queue_list; /* packets in queue */
};
typedef int (*nfqnl_cmpfn)(struct nfqnl_queue_entry *, unsigned long);
static DEFINE_RWLOCK(instances_lock);
#define INSTANCE_BUCKETS 16
static struct hlist_head instance_table[INSTANCE_BUCKETS];
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(inst, pos, head, hlist) {
if (inst->queue_num == queue_num)
return inst;
}
return NULL;
}
static struct nfqnl_instance *
instance_lookup_get(u_int16_t queue_num)
{
struct nfqnl_instance *inst;
read_lock_bh(&instances_lock);
inst = __instance_lookup(queue_num);
if (inst)
atomic_inc(&inst->use);
read_unlock_bh(&instances_lock);
return inst;
}
static void
instance_put(struct nfqnl_instance *inst)
{
if (inst && atomic_dec_and_test(&inst->use)) {
QDEBUG("kfree(inst=%p)\n", inst);
kfree(inst);
}
}
static struct nfqnl_instance *
instance_create(u_int16_t queue_num, int pid)
{
struct nfqnl_instance *inst;
QDEBUG("entering for queue_num=%u, pid=%d\n", queue_num, pid);
write_lock_bh(&instances_lock);
if (__instance_lookup(queue_num)) {
inst = NULL;
QDEBUG("aborting, instance already exists\n");
goto out_unlock;
}
inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
if (!inst)
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;
atomic_set(&inst->id_sequence, 0);
/* needs to be two, since we _put() after creation */
atomic_set(&inst->use, 2);
spin_lock_init(&inst->lock);
INIT_LIST_HEAD(&inst->queue_list);
if (!try_module_get(THIS_MODULE))
goto out_free;
hlist_add_head(&inst->hlist,
&instance_table[instance_hashfn(queue_num)]);
write_unlock_bh(&instances_lock);
QDEBUG("successfully created new instance\n");
return inst;
out_free:
kfree(inst);
out_unlock:
write_unlock_bh(&instances_lock);
return NULL;
}
static void nfqnl_flush(struct nfqnl_instance *queue, int verdict);
static void
_instance_destroy2(struct nfqnl_instance *inst, int lock)
{
/* first pull it out of the global list */
if (lock)
write_lock_bh(&instances_lock);
QDEBUG("removing instance %p (queuenum=%u) from hash\n",
inst, inst->queue_num);
hlist_del(&inst->hlist);
if (lock)
write_unlock_bh(&instances_lock);
/* then flush all pending skbs from the queue */
nfqnl_flush(inst, NF_DROP);
/* and finally put the refcount */
instance_put(inst);
module_put(THIS_MODULE);
}
static inline void
__instance_destroy(struct nfqnl_instance *inst)
{
_instance_destroy2(inst, 0);
}
static inline void
instance_destroy(struct nfqnl_instance *inst)
{
_instance_destroy2(inst, 1);
}
static void
issue_verdict(struct nfqnl_queue_entry *entry, int verdict)
{
QDEBUG("entering for entry %p, verdict %u\n", entry, verdict);
/* TCP input path (and probably other bits) assume to be called
* from softirq context, not from syscall, like issue_verdict is
* called. TCP input path deadlocks with locks taken from timer
* softirq, e.g. We therefore emulate this by local_bh_disable() */
local_bh_disable();
nf_reinject(entry->skb, entry->info, verdict);
local_bh_enable();
kfree(entry);
}
static inline void
__enqueue_entry(struct nfqnl_instance *queue,
struct nfqnl_queue_entry *entry)
{
list_add(&entry->list, &queue->queue_list);
queue->queue_total++;
}
/*
* Find and return a queued entry matched by cmpfn, or return the last
* entry if cmpfn is NULL.
*/
static inline struct nfqnl_queue_entry *
__find_entry(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
unsigned long data)
{
struct list_head *p;
list_for_each_prev(p, &queue->queue_list) {
struct nfqnl_queue_entry *entry = (struct nfqnl_queue_entry *)p;
if (!cmpfn || cmpfn(entry, data))
return entry;
}
return NULL;
}
static inline void
__dequeue_entry(struct nfqnl_instance *q, struct nfqnl_queue_entry *entry)
{
list_del(&entry->list);
q->queue_total--;
}
static inline struct nfqnl_queue_entry *
__find_dequeue_entry(struct nfqnl_instance *queue,
nfqnl_cmpfn cmpfn, unsigned long data)
{
struct nfqnl_queue_entry *entry;
entry = __find_entry(queue, cmpfn, data);
if (entry == NULL)
return NULL;
__dequeue_entry(queue, entry);
return entry;
}
static inline void
__nfqnl_flush(struct nfqnl_instance *queue, int verdict)
{
struct nfqnl_queue_entry *entry;
while ((entry = __find_dequeue_entry(queue, NULL, 0)))
issue_verdict(entry, verdict);
}
static inline int
__nfqnl_set_mode(struct nfqnl_instance *queue,
unsigned char mode, unsigned int range)
{
int status = 0;
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 nfattr which has 16bit nfa_len */
if (range > 0xffff)
queue->copy_range = 0xffff;
else
queue->copy_range = range;
break;
default:
status = -EINVAL;
}
return status;
}
static struct nfqnl_queue_entry *
find_dequeue_entry(struct nfqnl_instance *queue,
nfqnl_cmpfn cmpfn, unsigned long data)
{
struct nfqnl_queue_entry *entry;
spin_lock_bh(&queue->lock);
entry = __find_dequeue_entry(queue, cmpfn, data);
spin_unlock_bh(&queue->lock);
return entry;
}
static void
nfqnl_flush(struct nfqnl_instance *queue, int verdict)
{
spin_lock_bh(&queue->lock);
__nfqnl_flush(queue, verdict);
spin_unlock_bh(&queue->lock);
}
static struct sk_buff *
nfqnl_build_packet_message(struct nfqnl_instance *queue,
struct nfqnl_queue_entry *entry, int *errp)
{
sk_buff_data_t old_tail;
size_t size;
size_t data_len = 0;
struct sk_buff *skb;
struct nfqnl_msg_packet_hdr pmsg;
struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg;
struct nf_info *entinf = entry->info;
struct sk_buff *entskb = entry->skb;
struct net_device *indev;
struct net_device *outdev;
__be32 tmp_uint;
QDEBUG("entered\n");
/* all macros expand to constant values at compile time */
size = NLMSG_SPACE(sizeof(struct nfgenmsg)) +
+ NFA_SPACE(sizeof(struct nfqnl_msg_packet_hdr))
+ NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
+ NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
#ifdef CONFIG_BRIDGE_NETFILTER
+ NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
+ NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
#endif
+ NFA_SPACE(sizeof(u_int32_t)) /* mark */
+ NFA_SPACE(sizeof(struct nfqnl_msg_packet_hw))
+ NFA_SPACE(sizeof(struct nfqnl_msg_packet_timestamp));
outdev = entinf->outdev;
spin_lock_bh(&queue->lock);
switch (queue->copy_mode) {
case NFQNL_COPY_META:
case NFQNL_COPY_NONE:
data_len = 0;
break;
case NFQNL_COPY_PACKET:
if ((entskb->ip_summed == CHECKSUM_PARTIAL ||
entskb->ip_summed == CHECKSUM_COMPLETE) &&
(*errp = skb_checksum_help(entskb))) {
spin_unlock_bh(&queue->lock);
return NULL;
}
if (queue->copy_range == 0
|| queue->copy_range > entskb->len)
data_len = entskb->len;
else
data_len = queue->copy_range;
size += NFA_SPACE(data_len);
break;
default:
*errp = -EINVAL;
spin_unlock_bh(&queue->lock);
return NULL;
}
spin_unlock_bh(&queue->lock);
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 = entinf->pf;
nfmsg->version = NFNETLINK_V0;
nfmsg->res_id = htons(queue->queue_num);
pmsg.packet_id = htonl(entry->id);
pmsg.hw_protocol = entskb->protocol;
pmsg.hook = entinf->hook;
NFA_PUT(skb, NFQA_PACKET_HDR, sizeof(pmsg), &pmsg);
indev = entinf->indev;
if (indev) {
tmp_uint = htonl(indev->ifindex);
#ifndef CONFIG_BRIDGE_NETFILTER
NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint), &tmp_uint);
#else
if (entinf->pf == PF_BRIDGE) {
/* Case 1: indev is physical input device, we need to
* look for bridge group (when called from
* netfilter_bridge) */
NFA_PUT(skb, NFQA_IFINDEX_PHYSINDEV, sizeof(tmp_uint),
&tmp_uint);
/* this is the bridge group "brX" */
tmp_uint = htonl(indev->br_port->br->dev->ifindex);
NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint),
&tmp_uint);
} else {
/* Case 2: indev is bridge group, we need to look for
* physical device (when called from ipv4) */
NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint),
&tmp_uint);
if (entskb->nf_bridge
&& entskb->nf_bridge->physindev) {
tmp_uint = htonl(entskb->nf_bridge->physindev->ifindex);
NFA_PUT(skb, NFQA_IFINDEX_PHYSINDEV,
sizeof(tmp_uint), &tmp_uint);
}
}
#endif
}
if (outdev) {
tmp_uint = htonl(outdev->ifindex);
#ifndef CONFIG_BRIDGE_NETFILTER
NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint), &tmp_uint);
#else
if (entinf->pf == PF_BRIDGE) {
/* Case 1: outdev is physical output device, we need to
* look for bridge group (when called from
* netfilter_bridge) */
NFA_PUT(skb, NFQA_IFINDEX_PHYSOUTDEV, sizeof(tmp_uint),
&tmp_uint);
/* this is the bridge group "brX" */
tmp_uint = htonl(outdev->br_port->br->dev->ifindex);
NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint),
&tmp_uint);
} else {
/* Case 2: outdev is bridge group, we need to look for
* physical output device (when called from ipv4) */
NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint),
&tmp_uint);
if (entskb->nf_bridge
&& entskb->nf_bridge->physoutdev) {
tmp_uint = htonl(entskb->nf_bridge->physoutdev->ifindex);
NFA_PUT(skb, NFQA_IFINDEX_PHYSOUTDEV,
sizeof(tmp_uint), &tmp_uint);
}
}
#endif
}
if (entskb->mark) {
tmp_uint = htonl(entskb->mark);
NFA_PUT(skb, NFQA_MARK, sizeof(u_int32_t), &tmp_uint);
}
if (indev && entskb->dev
&& entskb->dev->hard_header_parse) {
struct nfqnl_msg_packet_hw phw;
int len = entskb->dev->hard_header_parse(entskb,
phw.hw_addr);
phw.hw_addrlen = htons(len);
NFA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
}
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);
NFA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts);
}
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(entskb, 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 "nf_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) {
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)) {
struct sk_buff *newskb;
newskb = skb_copy_expand(e->skb,
skb_headroom(e->skb),
diff,
GFP_ATOMIC);
if (newskb == NULL) {
printk(KERN_WARNING "nf_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;
skb_copy_to_linear_data(e->skb, data, data_len);
e->skb->ip_summed = CHECKSUM_NONE;
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)
{
struct nf_info *entinf = entry->info;
if (entinf->indev)
if (entinf->indev->ifindex == ifindex)
return 1;
if (entinf->outdev)
if (entinf->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;
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[])
{
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])
entry->skb->mark = ntohl(*(__be32 *)
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[])
{
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[])
{
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));
ret = nf_unregister_queue_handler(ntohs(cmd->pf), &nfqh);
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;
if (!queue) {
ret = -ENOENT;
goto out_put;
}
params = NFA_DATA(nfqa[NFQA_CFG_PARAMS-1]);
nfqnl_set_mode(queue, params->copy_mode,
ntohl(params->copy_range));
}
if (nfqa[NFQA_CFG_QUEUE_MAXLEN-1]) {
__be32 *queue_maxlen;
queue_maxlen = NFA_DATA(nfqa[NFQA_CFG_QUEUE_MAXLEN-1]);
spin_lock_bh(&queue->lock);
queue->queue_maxlen = ntohl(*queue_maxlen);
spin_unlock_bh(&queue->lock);
}
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, },
[NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict,
.attr_count = NFQA_MAX, },
[NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
.attr_count = NFQA_CFG_MAX, },
};
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;