--- /dev/null
+/*
+ * This is a module which is used for queueing packets and communicating with
+ * userspace via nfetlink.
+ *
+ * (C) 2005 by Harald Welte <laforge@netfilter.org>
+ *
+ * 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/notifier.h>
+#include <linux/netdevice.h>
+#include <linux/netfilter.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>
+
+#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 */
+
+ 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);
+
+u_int64_t htonll(u_int64_t in)
+{
+ u_int64_t out;
+ int i;
+
+ for (i = 0; i < sizeof(u_int64_t); i++)
+ ((u_int8_t *)&out)[sizeof(u_int64_t)-1] = ((u_int8_t *)&in)[i];
+
+ return out;
+}
+
+#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(u_int16_t queue_num)
+{
+ struct nfqnl_instance *inst;
+
+ read_lock_bh(&instances_lock);
+ inst = __instance_lookup(queue_num);
+ read_unlock_bh(&instances_lock);
+
+ return 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 = kmalloc(sizeof(*inst), GFP_ATOMIC);
+ if (!inst)
+ goto out_unlock;
+
+ memset(inst, 0, sizeof(*inst));
+ 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);
+ inst->lock = SPIN_LOCK_UNLOCKED;
+ 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 free the data structure */
+ kfree(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)
+{
+ unsigned char *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;
+ unsigned int tmp_uint;
+
+ QDEBUG("entered\n");
+
+ /* all macros expand to constant values at compile time */
+ size = NLMSG_SPACE(sizeof(struct nfqnl_msg_packet_hdr))
+ + NLMSG_SPACE(sizeof(u_int32_t)) /* ifindex */
+ + NLMSG_SPACE(sizeof(u_int32_t)) /* ifindex */
+ + NLMSG_SPACE(sizeof(u_int32_t)) /* mark */
+ + NLMSG_SPACE(sizeof(struct nfqnl_msg_packet_hw))
+ + NLMSG_SPACE(sizeof(struct nfqnl_msg_packet_timestamp));
+
+ 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 (queue->copy_range == 0
+ || queue->copy_range > entry->skb->len)
+ data_len = entry->skb->len;
+ else
+ data_len = queue->copy_range;
+
+ size += NLMSG_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 = entry->info->pf;
+ nfmsg->version = NFNETLINK_V0;
+ nfmsg->res_id = htons(queue->queue_num);
+
+ pmsg.packet_id = htonl(entry->id);
+ pmsg.hw_protocol = htons(entry->skb->protocol);
+ pmsg.hook = entry->info->hook;
+
+ NFA_PUT(skb, NFQA_PACKET_HDR, sizeof(pmsg), &pmsg);
+
+ if (entry->info->indev) {
+ tmp_uint = htonl(entry->info->indev->ifindex);
+ NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint), &tmp_uint);
+ }
+
+ if (entry->info->outdev) {
+ tmp_uint = htonl(entry->info->outdev->ifindex);
+ NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint), &tmp_uint);
+ }
+
+ if (entry->skb->nfmark) {
+ tmp_uint = htonl(entry->skb->nfmark);
+ NFA_PUT(skb, NFQA_MARK, sizeof(u_int32_t), &tmp_uint);
+ }
+
+ if (entry->info->indev && entry->skb->dev
+ && entry->skb->dev->hard_header_parse) {
+ struct nfqnl_msg_packet_hw phw;
+
+ phw.hw_addrlen =
+ entry->skb->dev->hard_header_parse(entry->skb,
+ phw.hw_addr);
+ phw.hw_addrlen = htons(phw.hw_addrlen);
+ NFA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
+ }
+
+ if (entry->skb->stamp.tv_sec) {
+ struct nfqnl_msg_packet_timestamp ts;
+
+ ts.sec = htonll(entry->skb->stamp.tv_sec);
+ ts.usec = htonll(entry->skb->stamp.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(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(queuenum);
+ if (!queue) {
+ QDEBUG("no queue instance matching\n");
+ return -EINVAL;
+ }
+
+ if (queue->copy_mode == NFQNL_COPY_NONE) {
+ QDEBUG("mode COPY_NONE, aborting\n");
+ return -EAGAIN;
+ }
+
+ entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
+ if (entry == NULL) {
+ if (net_ratelimit())
+ printk(KERN_ERR
+ "nf_queue: OOM in nfqnl_enqueue_packet()\n");
+ return -ENOMEM;
+ }
+
+ 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);
+ return status;
+
+err_out_free_nskb:
+ kfree_skb(nskb);
+
+err_out_unlock:
+ spin_unlock_bh(&queue->lock);
+
+err_out_free:
+ kfree(entry);
+ 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 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;
+
+ queue = instance_lookup(queue_num);
+ if (!queue)
+ return -ENODEV;
+
+ if (queue->peer_pid != NETLINK_CB(skb).pid)
+ return -EPERM;
+
+ if (!nfqa[NFQA_VERDICT_HDR-1])
+ return -EINVAL;
+
+ vhdr = NFA_DATA(nfqa[NFQA_VERDICT_HDR-1]);
+ verdict = ntohl(vhdr->verdict);
+
+ if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT)
+ return -EINVAL;
+
+ entry = find_dequeue_entry(queue, id_cmp, ntohl(vhdr->id));
+ if (entry == NULL)
+ return -ENOENT;
+
+ 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);
+ return 0;
+}
+
+static int
+nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
+ struct nlmsghdr *nlh, struct nfattr *nfqa[], int *errp)
+{
+ return -ENOTSUPP;
+}
+
+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;
+
+ QDEBUG("entering for msg %u\n", NFNL_MSG_TYPE(nlh->nlmsg_type));
+
+ queue = instance_lookup(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)
+ return -EPERM;
+
+ instance_destroy(queue);
+ break;
+ case NFQNL_CFG_CMD_PF_BIND:
+ QDEBUG("registering queue handler for pf=%u\n",
+ ntohs(cmd->pf));
+ return nf_register_queue_handler(ntohs(cmd->pf),
+ nfqnl_enqueue_packet,
+ NULL);
+
+ 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(!) */
+ return nf_unregister_queue_handler(ntohs(cmd->pf));
+ break;
+ default:
+ return -EINVAL;
+ }
+ } else {
+ if (!queue) {
+ QDEBUG("no config command, and no instance ENOENT\n");
+ return -ENOENT;
+ }
+
+ if (queue->peer_pid != NETLINK_CB(skb).pid) {
+ QDEBUG("no config command, and wrong pid\n");
+ return -EPERM;
+ }
+ }
+
+ 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));
+ }
+
+ return 0;
+}
+
+static struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
+ [NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp,
+ .cap_required = CAP_NET_ADMIN },
+ [NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict,
+ .cap_required = CAP_NET_ADMIN },
+ [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
+ .cap_required = CAP_NET_ADMIN },
+};
+
+static struct nfnetlink_subsystem nfqnl_subsys = {
+ .name = "nf_queue",
+ .subsys_id = NFNL_SUBSYS_QUEUE,
+ .cb_count = NFQNL_MSG_MAX,
+ .attr_count = NFQA_MAX,
+ .cb = nfqnl_cb,
+};
+
+static int
+init_or_cleanup(int init)
+{
+ int status = -ENOMEM;
+
+ if (!init)
+ goto cleanup;
+
+ 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;
+ }
+
+ register_netdevice_notifier(&nfqnl_dev_notifier);
+ return status;
+
+cleanup:
+ nf_unregister_queue_handlers(nfqnl_enqueue_packet);
+ unregister_netdevice_notifier(&nfqnl_dev_notifier);
+ 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);
projects / linux-2.6 / commitdiff