![Johannes Berg](/assets/img/avatar_default.png)
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1595 lines
39 KiB
C
1595 lines
39 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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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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_bridge.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/netfilter/nf_conntrack_common.h>
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#include <linux/list.h>
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#include <net/sock.h>
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#include <net/tcp_states.h>
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#include <net/netfilter/nf_queue.h>
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#include <net/netns/generic.h>
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#include <linux/atomic.h>
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#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
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#include "../bridge/br_private.h"
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#endif
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#if IS_ENABLED(CONFIG_NF_CONNTRACK)
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#include <net/netfilter/nf_conntrack.h>
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#endif
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#define NFQNL_QMAX_DEFAULT 1024
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/* We're using struct nlattr which has 16bit nla_len. Note that nla_len
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* includes the header length. Thus, the maximum packet length that we
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* support is 65531 bytes. We send truncated packets if the specified length
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* is larger than that. Userspace can check for presence of NFQA_CAP_LEN
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* attribute to detect truncation.
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*/
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#define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN)
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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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u32 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 ____cacheline_aligned_in_smp;
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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 unsigned int nfnl_queue_net_id __read_mostly;
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#define INSTANCE_BUCKETS 16
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struct nfnl_queue_net {
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spinlock_t instances_lock;
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struct hlist_head instance_table[INSTANCE_BUCKETS];
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};
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static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net)
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{
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return net_generic(net, nfnl_queue_net_id);
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}
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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(struct nfnl_queue_net *q, 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 = &q->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(struct nfnl_queue_net *q, u_int16_t queue_num, u32 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(&q->instances_lock);
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if (instance_lookup(q, 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 = NFQNL_MAX_COPY_RANGE;
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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, &q->instance_table[h]);
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spin_unlock(&q->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(&q->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 nfnl_queue_net *q, struct nfqnl_instance *inst)
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{
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spin_lock(&q->instances_lock);
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__instance_destroy(inst);
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spin_unlock(&q->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 nfqnl_reinject(struct nf_queue_entry *entry, unsigned int verdict)
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{
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struct nf_ct_hook *ct_hook;
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int err;
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if (verdict == NF_ACCEPT ||
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verdict == NF_REPEAT ||
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verdict == NF_STOP) {
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rcu_read_lock();
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ct_hook = rcu_dereference(nf_ct_hook);
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if (ct_hook) {
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err = ct_hook->update(entry->state.net, entry->skb);
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if (err < 0)
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verdict = NF_DROP;
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}
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rcu_read_unlock();
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}
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nf_reinject(entry, verdict);
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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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nfqnl_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 int
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nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
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bool csum_verify)
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{
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__u32 flags = 0;
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if (packet->ip_summed == CHECKSUM_PARTIAL)
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flags = NFQA_SKB_CSUMNOTREADY;
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else if (csum_verify)
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flags = NFQA_SKB_CSUM_NOTVERIFIED;
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if (skb_is_gso(packet))
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flags |= NFQA_SKB_GSO;
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return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0;
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}
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static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
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{
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const struct cred *cred;
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if (!sk_fullsock(sk))
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return 0;
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read_lock_bh(&sk->sk_callback_lock);
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if (sk->sk_socket && sk->sk_socket->file) {
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cred = sk->sk_socket->file->f_cred;
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if (nla_put_be32(skb, NFQA_UID,
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htonl(from_kuid_munged(&init_user_ns, cred->fsuid))))
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goto nla_put_failure;
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if (nla_put_be32(skb, NFQA_GID,
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htonl(from_kgid_munged(&init_user_ns, cred->fsgid))))
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goto nla_put_failure;
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}
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read_unlock_bh(&sk->sk_callback_lock);
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return 0;
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nla_put_failure:
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read_unlock_bh(&sk->sk_callback_lock);
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return -1;
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}
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static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
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{
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u32 seclen = 0;
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#if IS_ENABLED(CONFIG_NETWORK_SECMARK)
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if (!skb || !sk_fullsock(skb->sk))
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return 0;
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read_lock_bh(&skb->sk->sk_callback_lock);
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if (skb->secmark)
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security_secid_to_secctx(skb->secmark, secdata, &seclen);
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read_unlock_bh(&skb->sk->sk_callback_lock);
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#endif
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return seclen;
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}
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static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
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{
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struct sk_buff *entskb = entry->skb;
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u32 nlalen = 0;
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if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
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return 0;
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if (skb_vlan_tag_present(entskb))
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nlalen += nla_total_size(nla_total_size(sizeof(__be16)) +
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nla_total_size(sizeof(__be16)));
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if (entskb->network_header > entskb->mac_header)
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nlalen += nla_total_size((entskb->network_header -
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entskb->mac_header));
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return nlalen;
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}
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static int nfqnl_put_bridge(struct nf_queue_entry *entry, struct sk_buff *skb)
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{
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struct sk_buff *entskb = entry->skb;
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if (entry->state.pf != PF_BRIDGE || !skb_mac_header_was_set(entskb))
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return 0;
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if (skb_vlan_tag_present(entskb)) {
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struct nlattr *nest;
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nest = nla_nest_start(skb, NFQA_VLAN);
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if (!nest)
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goto nla_put_failure;
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if (nla_put_be16(skb, NFQA_VLAN_TCI, htons(entskb->vlan_tci)) ||
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nla_put_be16(skb, NFQA_VLAN_PROTO, entskb->vlan_proto))
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goto nla_put_failure;
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nla_nest_end(skb, nest);
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}
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if (entskb->mac_header < entskb->network_header) {
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int len = (int)(entskb->network_header - entskb->mac_header);
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if (nla_put(skb, NFQA_L2HDR, len, skb_mac_header(entskb)))
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goto nla_put_failure;
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}
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return 0;
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nla_put_failure:
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return -1;
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}
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static struct sk_buff *
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nfqnl_build_packet_message(struct net *net, 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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size_t size;
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size_t data_len = 0, cap_len = 0;
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unsigned int hlen = 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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struct nfnl_ct_hook *nfnl_ct;
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bool csum_verify;
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char *secdata = NULL;
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u32 seclen = 0;
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size = nlmsg_total_size(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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#if IS_ENABLED(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(u_int32_t)) /* skbinfo */
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+ nla_total_size(sizeof(u_int32_t)); /* cap_len */
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if (entskb->tstamp)
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size += nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp));
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size += nfqnl_get_bridge_size(entry);
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|
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if (entry->state.hook <= NF_INET_FORWARD ||
|
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(entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL))
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csum_verify = !skb_csum_unnecessary(entskb);
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else
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csum_verify = false;
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|
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outdev = entry->state.out;
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|
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switch ((enum nfqnl_config_mode)READ_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 (!(queue->flags & NFQA_CFG_F_GSO) &&
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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 = READ_ONCE(queue->copy_range);
|
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if (data_len > entskb->len)
|
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data_len = entskb->len;
|
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|
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hlen = skb_zerocopy_headlen(entskb);
|
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hlen = min_t(unsigned int, hlen, data_len);
|
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size += sizeof(struct nlattr) + hlen;
|
|
cap_len = entskb->len;
|
|
break;
|
|
}
|
|
|
|
nfnl_ct = rcu_dereference(nfnl_ct_hook);
|
|
|
|
if (queue->flags & NFQA_CFG_F_CONNTRACK) {
|
|
if (nfnl_ct != NULL) {
|
|
ct = nfnl_ct->get_ct(entskb, &ctinfo);
|
|
if (ct != NULL)
|
|
size += nfnl_ct->build_size(ct);
|
|
}
|
|
}
|
|
|
|
if (queue->flags & NFQA_CFG_F_UID_GID) {
|
|
size += (nla_total_size(sizeof(u_int32_t)) /* uid */
|
|
+ nla_total_size(sizeof(u_int32_t))); /* gid */
|
|
}
|
|
|
|
if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
|
|
seclen = nfqnl_get_sk_secctx(entskb, &secdata);
|
|
if (seclen)
|
|
size += nla_total_size(seclen);
|
|
}
|
|
|
|
skb = alloc_skb(size, GFP_ATOMIC);
|
|
if (!skb) {
|
|
skb_tx_error(entskb);
|
|
goto nlmsg_failure;
|
|
}
|
|
|
|
nlh = nlmsg_put(skb, 0, 0,
|
|
nfnl_msg_type(NFNL_SUBSYS_QUEUE, NFQNL_MSG_PACKET),
|
|
sizeof(struct nfgenmsg), 0);
|
|
if (!nlh) {
|
|
skb_tx_error(entskb);
|
|
kfree_skb(skb);
|
|
goto nlmsg_failure;
|
|
}
|
|
nfmsg = nlmsg_data(nlh);
|
|
nfmsg->nfgen_family = entry->state.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->state.hook;
|
|
*packet_id_ptr = &pmsg->packet_id;
|
|
|
|
indev = entry->state.in;
|
|
if (indev) {
|
|
#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
|
|
if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex)))
|
|
goto nla_put_failure;
|
|
#else
|
|
if (entry->state.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 {
|
|
int physinif;
|
|
|
|
/* 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;
|
|
|
|
physinif = nf_bridge_get_physinif(entskb);
|
|
if (physinif &&
|
|
nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV,
|
|
htonl(physinif)))
|
|
goto nla_put_failure;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
if (outdev) {
|
|
#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
|
|
if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex)))
|
|
goto nla_put_failure;
|
|
#else
|
|
if (entry->state.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 {
|
|
int physoutif;
|
|
|
|
/* 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;
|
|
|
|
physoutif = nf_bridge_get_physoutif(entskb);
|
|
if (physoutif &&
|
|
nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV,
|
|
htonl(physoutif)))
|
|
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;
|
|
|
|
memset(&phw, 0, sizeof(phw));
|
|
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 (nfqnl_put_bridge(entry, skb) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (entry->state.hook <= NF_INET_FORWARD && entskb->tstamp) {
|
|
struct nfqnl_msg_packet_timestamp ts;
|
|
struct timespec64 kts = ktime_to_timespec64(entskb->tstamp);
|
|
|
|
ts.sec = cpu_to_be64(kts.tv_sec);
|
|
ts.usec = cpu_to_be64(kts.tv_nsec / NSEC_PER_USEC);
|
|
|
|
if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts))
|
|
goto nla_put_failure;
|
|
}
|
|
|
|
if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk &&
|
|
nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
|
|
goto nla_put_failure;
|
|
|
|
if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (cap_len > data_len &&
|
|
nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len)))
|
|
goto nla_put_failure;
|
|
|
|
if (nfqnl_put_packet_info(skb, entskb, csum_verify))
|
|
goto nla_put_failure;
|
|
|
|
if (data_len) {
|
|
struct nlattr *nla;
|
|
|
|
if (skb_tailroom(skb) < sizeof(*nla) + hlen)
|
|
goto nla_put_failure;
|
|
|
|
nla = skb_put(skb, sizeof(*nla));
|
|
nla->nla_type = NFQA_PAYLOAD;
|
|
nla->nla_len = nla_attr_size(data_len);
|
|
|
|
if (skb_zerocopy(skb, entskb, data_len, hlen))
|
|
goto nla_put_failure;
|
|
}
|
|
|
|
nlh->nlmsg_len = skb->len;
|
|
if (seclen)
|
|
security_release_secctx(secdata, seclen);
|
|
return skb;
|
|
|
|
nla_put_failure:
|
|
skb_tx_error(entskb);
|
|
kfree_skb(skb);
|
|
net_err_ratelimited("nf_queue: error creating packet message\n");
|
|
nlmsg_failure:
|
|
if (seclen)
|
|
security_release_secctx(secdata, seclen);
|
|
return NULL;
|
|
}
|
|
|
|
static bool nf_ct_drop_unconfirmed(const struct nf_queue_entry *entry)
|
|
{
|
|
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
|
|
static const unsigned long flags = IPS_CONFIRMED | IPS_DYING;
|
|
const struct nf_conn *ct = (void *)skb_nfct(entry->skb);
|
|
|
|
if (ct && ((ct->status & flags) == IPS_DYING))
|
|
return true;
|
|
#endif
|
|
return false;
|
|
}
|
|
|
|
static int
|
|
__nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue,
|
|
struct nf_queue_entry *entry)
|
|
{
|
|
struct sk_buff *nskb;
|
|
int err = -ENOBUFS;
|
|
__be32 *packet_id_ptr;
|
|
int failopen = 0;
|
|
|
|
nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr);
|
|
if (nskb == NULL) {
|
|
err = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
spin_lock_bh(&queue->lock);
|
|
|
|
if (nf_ct_drop_unconfirmed(entry))
|
|
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, net, queue->peer_portid, MSG_DONTWAIT);
|
|
if (err < 0) {
|
|
if (queue->flags & NFQA_CFG_F_FAIL_OPEN) {
|
|
failopen = 1;
|
|
err = 0;
|
|
} else {
|
|
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)
|
|
nfqnl_reinject(entry, NF_ACCEPT);
|
|
err_out:
|
|
return err;
|
|
}
|
|
|
|
static struct nf_queue_entry *
|
|
nf_queue_entry_dup(struct nf_queue_entry *e)
|
|
{
|
|
struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC);
|
|
if (entry)
|
|
nf_queue_entry_get_refs(entry);
|
|
return entry;
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
|
|
/* When called from bridge netfilter, skb->data must point to MAC header
|
|
* before calling skb_gso_segment(). Else, original MAC header is lost
|
|
* and segmented skbs will be sent to wrong destination.
|
|
*/
|
|
static void nf_bridge_adjust_skb_data(struct sk_buff *skb)
|
|
{
|
|
if (nf_bridge_info_get(skb))
|
|
__skb_push(skb, skb->network_header - skb->mac_header);
|
|
}
|
|
|
|
static void nf_bridge_adjust_segmented_data(struct sk_buff *skb)
|
|
{
|
|
if (nf_bridge_info_get(skb))
|
|
__skb_pull(skb, skb->network_header - skb->mac_header);
|
|
}
|
|
#else
|
|
#define nf_bridge_adjust_skb_data(s) do {} while (0)
|
|
#define nf_bridge_adjust_segmented_data(s) do {} while (0)
|
|
#endif
|
|
|
|
static void free_entry(struct nf_queue_entry *entry)
|
|
{
|
|
nf_queue_entry_release_refs(entry);
|
|
kfree(entry);
|
|
}
|
|
|
|
static int
|
|
__nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
|
|
struct sk_buff *skb, struct nf_queue_entry *entry)
|
|
{
|
|
int ret = -ENOMEM;
|
|
struct nf_queue_entry *entry_seg;
|
|
|
|
nf_bridge_adjust_segmented_data(skb);
|
|
|
|
if (skb->next == NULL) { /* last packet, no need to copy entry */
|
|
struct sk_buff *gso_skb = entry->skb;
|
|
entry->skb = skb;
|
|
ret = __nfqnl_enqueue_packet(net, queue, entry);
|
|
if (ret)
|
|
entry->skb = gso_skb;
|
|
return ret;
|
|
}
|
|
|
|
skb_mark_not_on_list(skb);
|
|
|
|
entry_seg = nf_queue_entry_dup(entry);
|
|
if (entry_seg) {
|
|
entry_seg->skb = skb;
|
|
ret = __nfqnl_enqueue_packet(net, queue, entry_seg);
|
|
if (ret)
|
|
free_entry(entry_seg);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
|
|
{
|
|
unsigned int queued;
|
|
struct nfqnl_instance *queue;
|
|
struct sk_buff *skb, *segs;
|
|
int err = -ENOBUFS;
|
|
struct net *net = entry->state.net;
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
|
|
/* rcu_read_lock()ed by nf_hook_thresh */
|
|
queue = instance_lookup(q, queuenum);
|
|
if (!queue)
|
|
return -ESRCH;
|
|
|
|
if (queue->copy_mode == NFQNL_COPY_NONE)
|
|
return -EINVAL;
|
|
|
|
skb = entry->skb;
|
|
|
|
switch (entry->state.pf) {
|
|
case NFPROTO_IPV4:
|
|
skb->protocol = htons(ETH_P_IP);
|
|
break;
|
|
case NFPROTO_IPV6:
|
|
skb->protocol = htons(ETH_P_IPV6);
|
|
break;
|
|
}
|
|
|
|
if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb))
|
|
return __nfqnl_enqueue_packet(net, queue, entry);
|
|
|
|
nf_bridge_adjust_skb_data(skb);
|
|
segs = skb_gso_segment(skb, 0);
|
|
/* Does not use PTR_ERR to limit the number of error codes that can be
|
|
* returned by nf_queue. For instance, callers rely on -ESRCH to
|
|
* mean 'ignore this hook'.
|
|
*/
|
|
if (IS_ERR_OR_NULL(segs))
|
|
goto out_err;
|
|
queued = 0;
|
|
err = 0;
|
|
do {
|
|
struct sk_buff *nskb = segs->next;
|
|
if (err == 0)
|
|
err = __nfqnl_enqueue_packet_gso(net, queue,
|
|
segs, entry);
|
|
if (err == 0)
|
|
queued++;
|
|
else
|
|
kfree_skb(segs);
|
|
segs = nskb;
|
|
} while (segs);
|
|
|
|
if (queued) {
|
|
if (err) /* some segments are already queued */
|
|
free_entry(entry);
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
out_err:
|
|
nf_bridge_adjust_segmented_data(skb);
|
|
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)
|
|
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;
|
|
if (range == 0 || range > NFQNL_MAX_COPY_RANGE)
|
|
queue->copy_range = NFQNL_MAX_COPY_RANGE;
|
|
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 IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
|
|
int physinif, physoutif;
|
|
|
|
physinif = nf_bridge_get_physinif(entry->skb);
|
|
physoutif = nf_bridge_get_physoutif(entry->skb);
|
|
|
|
if (physinif == ifindex || physoutif == ifindex)
|
|
return 1;
|
|
#endif
|
|
if (entry->state.in)
|
|
if (entry->state.in->ifindex == ifindex)
|
|
return 1;
|
|
if (entry->state.out)
|
|
if (entry->state.out->ifindex == ifindex)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* drop all packets with either indev or outdev == ifindex from all queue
|
|
* instances */
|
|
static void
|
|
nfqnl_dev_drop(struct net *net, int ifindex)
|
|
{
|
|
int i;
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
|
|
rcu_read_lock();
|
|
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++) {
|
|
struct nfqnl_instance *inst;
|
|
struct hlist_head *head = &q->instance_table[i];
|
|
|
|
hlist_for_each_entry_rcu(inst, head, hlist)
|
|
nfqnl_flush(inst, dev_cmp, ifindex);
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static int
|
|
nfqnl_rcv_dev_event(struct notifier_block *this,
|
|
unsigned long event, void *ptr)
|
|
{
|
|
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
|
|
|
|
/* Drop any packets associated with the downed device */
|
|
if (event == NETDEV_DOWN)
|
|
nfqnl_dev_drop(dev_net(dev), dev->ifindex);
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block nfqnl_dev_notifier = {
|
|
.notifier_call = nfqnl_rcv_dev_event,
|
|
};
|
|
|
|
static void nfqnl_nf_hook_drop(struct net *net)
|
|
{
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
int i;
|
|
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++) {
|
|
struct nfqnl_instance *inst;
|
|
struct hlist_head *head = &q->instance_table[i];
|
|
|
|
hlist_for_each_entry_rcu(inst, head, hlist)
|
|
nfqnl_flush(inst, NULL, 0);
|
|
}
|
|
}
|
|
|
|
static int
|
|
nfqnl_rcv_nl_event(struct notifier_block *this,
|
|
unsigned long event, void *ptr)
|
|
{
|
|
struct netlink_notify *n = ptr;
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(n->net);
|
|
|
|
if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
|
|
int i;
|
|
|
|
/* destroy all instances for this portid */
|
|
spin_lock(&q->instances_lock);
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++) {
|
|
struct hlist_node *t2;
|
|
struct nfqnl_instance *inst;
|
|
struct hlist_head *head = &q->instance_table[i];
|
|
|
|
hlist_for_each_entry_safe(inst, t2, head, hlist) {
|
|
if (n->portid == inst->peer_portid)
|
|
__instance_destroy(inst);
|
|
}
|
|
}
|
|
spin_unlock(&q->instances_lock);
|
|
}
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block nfqnl_rtnl_notifier = {
|
|
.notifier_call = nfqnl_rcv_nl_event,
|
|
};
|
|
|
|
static const struct nla_policy nfqa_vlan_policy[NFQA_VLAN_MAX + 1] = {
|
|
[NFQA_VLAN_TCI] = { .type = NLA_U16},
|
|
[NFQA_VLAN_PROTO] = { .type = NLA_U16},
|
|
};
|
|
|
|
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 },
|
|
[NFQA_EXP] = { .type = NLA_UNSPEC },
|
|
[NFQA_VLAN] = { .type = NLA_NESTED },
|
|
};
|
|
|
|
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(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid)
|
|
{
|
|
struct nfqnl_instance *queue;
|
|
|
|
queue = instance_lookup(q, 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 net *net, struct sock *ctnl,
|
|
struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
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);
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
|
|
queue = verdict_instance_lookup(q, 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]));
|
|
|
|
nfqnl_reinject(entry, verdict);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct nf_conn *nfqnl_ct_parse(struct nfnl_ct_hook *nfnl_ct,
|
|
const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[],
|
|
struct nf_queue_entry *entry,
|
|
enum ip_conntrack_info *ctinfo)
|
|
{
|
|
struct nf_conn *ct;
|
|
|
|
ct = nfnl_ct->get_ct(entry->skb, ctinfo);
|
|
if (ct == NULL)
|
|
return NULL;
|
|
|
|
if (nfnl_ct->parse(nfqa[NFQA_CT], ct) < 0)
|
|
return NULL;
|
|
|
|
if (nfqa[NFQA_EXP])
|
|
nfnl_ct->attach_expect(nfqa[NFQA_EXP], ct,
|
|
NETLINK_CB(entry->skb).portid,
|
|
nlmsg_report(nlh));
|
|
return ct;
|
|
}
|
|
|
|
static int nfqa_parse_bridge(struct nf_queue_entry *entry,
|
|
const struct nlattr * const nfqa[])
|
|
{
|
|
if (nfqa[NFQA_VLAN]) {
|
|
struct nlattr *tb[NFQA_VLAN_MAX + 1];
|
|
int err;
|
|
|
|
err = nla_parse_nested_deprecated(tb, NFQA_VLAN_MAX,
|
|
nfqa[NFQA_VLAN],
|
|
nfqa_vlan_policy, NULL);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (!tb[NFQA_VLAN_TCI] || !tb[NFQA_VLAN_PROTO])
|
|
return -EINVAL;
|
|
|
|
__vlan_hwaccel_put_tag(entry->skb,
|
|
nla_get_be16(tb[NFQA_VLAN_PROTO]),
|
|
ntohs(nla_get_be16(tb[NFQA_VLAN_TCI])));
|
|
}
|
|
|
|
if (nfqa[NFQA_L2HDR]) {
|
|
int mac_header_len = entry->skb->network_header -
|
|
entry->skb->mac_header;
|
|
|
|
if (mac_header_len != nla_len(nfqa[NFQA_L2HDR]))
|
|
return -EINVAL;
|
|
else if (mac_header_len > 0)
|
|
memcpy(skb_mac_header(entry->skb),
|
|
nla_data(nfqa[NFQA_L2HDR]),
|
|
mac_header_len);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int nfqnl_recv_verdict(struct net *net, struct sock *ctnl,
|
|
struct sk_buff *skb,
|
|
const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
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 nfnl_ct_hook *nfnl_ct;
|
|
struct nf_conn *ct = NULL;
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
int err;
|
|
|
|
queue = verdict_instance_lookup(q, 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 lock already held from nfnl->call_rcu. */
|
|
nfnl_ct = rcu_dereference(nfnl_ct_hook);
|
|
|
|
if (nfqa[NFQA_CT]) {
|
|
if (nfnl_ct != NULL)
|
|
ct = nfqnl_ct_parse(nfnl_ct, nlh, nfqa, entry, &ctinfo);
|
|
}
|
|
|
|
if (entry->state.pf == PF_BRIDGE) {
|
|
err = nfqa_parse_bridge(entry, nfqa);
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
|
|
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 && diff)
|
|
nfnl_ct->seq_adjust(entry->skb, ct, ctinfo, diff);
|
|
}
|
|
|
|
if (nfqa[NFQA_MARK])
|
|
entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK]));
|
|
|
|
nfqnl_reinject(entry, verdict);
|
|
return 0;
|
|
}
|
|
|
|
static int nfqnl_recv_unsupp(struct net *net, struct sock *ctnl,
|
|
struct sk_buff *skb, const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
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) },
|
|
[NFQA_CFG_QUEUE_MAXLEN] = { .type = NLA_U32 },
|
|
[NFQA_CFG_MASK] = { .type = NLA_U32 },
|
|
[NFQA_CFG_FLAGS] = { .type = NLA_U32 },
|
|
};
|
|
|
|
static const struct nf_queue_handler nfqh = {
|
|
.outfn = nfqnl_enqueue_packet,
|
|
.nf_hook_drop = nfqnl_nf_hook_drop,
|
|
};
|
|
|
|
static int nfqnl_recv_config(struct net *net, struct sock *ctnl,
|
|
struct sk_buff *skb, const struct nlmsghdr *nlh,
|
|
const struct nlattr * const nfqa[],
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
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;
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
__u32 flags = 0, mask = 0;
|
|
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;
|
|
}
|
|
}
|
|
|
|
/* Check if we support these flags in first place, dependencies should
|
|
* be there too not to break atomicity.
|
|
*/
|
|
if (nfqa[NFQA_CFG_FLAGS]) {
|
|
if (!nfqa[NFQA_CFG_MASK]) {
|
|
/* A mask is needed to specify which flags are being
|
|
* changed.
|
|
*/
|
|
return -EINVAL;
|
|
}
|
|
|
|
flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS]));
|
|
mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK]));
|
|
|
|
if (flags >= NFQA_CFG_F_MAX)
|
|
return -EOPNOTSUPP;
|
|
|
|
#if !IS_ENABLED(CONFIG_NETWORK_SECMARK)
|
|
if (flags & mask & NFQA_CFG_F_SECCTX)
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
if ((flags & mask & NFQA_CFG_F_CONNTRACK) &&
|
|
!rcu_access_pointer(nfnl_ct_hook)) {
|
|
#ifdef CONFIG_MODULES
|
|
nfnl_unlock(NFNL_SUBSYS_QUEUE);
|
|
request_module("ip_conntrack_netlink");
|
|
nfnl_lock(NFNL_SUBSYS_QUEUE);
|
|
if (rcu_access_pointer(nfnl_ct_hook))
|
|
return -EAGAIN;
|
|
#endif
|
|
return -EOPNOTSUPP;
|
|
}
|
|
}
|
|
|
|
rcu_read_lock();
|
|
queue = instance_lookup(q, 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(q, 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(q, queue);
|
|
goto err_out_unlock;
|
|
case NFQNL_CFG_CMD_PF_BIND:
|
|
case NFQNL_CFG_CMD_PF_UNBIND:
|
|
break;
|
|
default:
|
|
ret = -ENOTSUPP;
|
|
goto err_out_unlock;
|
|
}
|
|
}
|
|
|
|
if (!queue) {
|
|
ret = -ENODEV;
|
|
goto err_out_unlock;
|
|
}
|
|
|
|
if (nfqa[NFQA_CFG_PARAMS]) {
|
|
struct nfqnl_msg_config_params *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 = 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]) {
|
|
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 {
|
|
struct seq_net_private p;
|
|
unsigned int bucket;
|
|
};
|
|
|
|
static struct hlist_node *get_first(struct seq_file *seq)
|
|
{
|
|
struct iter_state *st = seq->private;
|
|
struct net *net;
|
|
struct nfnl_queue_net *q;
|
|
|
|
if (!st)
|
|
return NULL;
|
|
|
|
net = seq_file_net(seq);
|
|
q = nfnl_queue_pernet(net);
|
|
for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
|
|
if (!hlist_empty(&q->instance_table[st->bucket]))
|
|
return q->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;
|
|
struct net *net = seq_file_net(seq);
|
|
|
|
h = h->next;
|
|
while (!h) {
|
|
struct nfnl_queue_net *q;
|
|
|
|
if (++st->bucket >= INSTANCE_BUCKETS)
|
|
return NULL;
|
|
|
|
q = nfnl_queue_pernet(net);
|
|
h = q->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 *s, loff_t *pos)
|
|
__acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
|
|
{
|
|
spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
|
|
return get_idx(s, *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(nfnl_queue_pernet(seq_file_net(s))->instances_lock)
|
|
{
|
|
spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock);
|
|
}
|
|
|
|
static int seq_show(struct seq_file *s, void *v)
|
|
{
|
|
const struct nfqnl_instance *inst = v;
|
|
|
|
seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %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);
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations nfqnl_seq_ops = {
|
|
.start = seq_start,
|
|
.next = seq_next,
|
|
.stop = seq_stop,
|
|
.show = seq_show,
|
|
};
|
|
#endif /* PROC_FS */
|
|
|
|
static int __net_init nfnl_queue_net_init(struct net *net)
|
|
{
|
|
unsigned int i;
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++)
|
|
INIT_HLIST_HEAD(&q->instance_table[i]);
|
|
|
|
spin_lock_init(&q->instances_lock);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
if (!proc_create_net("nfnetlink_queue", 0440, net->nf.proc_netfilter,
|
|
&nfqnl_seq_ops, sizeof(struct iter_state)))
|
|
return -ENOMEM;
|
|
#endif
|
|
nf_register_queue_handler(net, &nfqh);
|
|
return 0;
|
|
}
|
|
|
|
static void __net_exit nfnl_queue_net_exit(struct net *net)
|
|
{
|
|
struct nfnl_queue_net *q = nfnl_queue_pernet(net);
|
|
unsigned int i;
|
|
|
|
nf_unregister_queue_handler(net);
|
|
#ifdef CONFIG_PROC_FS
|
|
remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter);
|
|
#endif
|
|
for (i = 0; i < INSTANCE_BUCKETS; i++)
|
|
WARN_ON_ONCE(!hlist_empty(&q->instance_table[i]));
|
|
}
|
|
|
|
static void nfnl_queue_net_exit_batch(struct list_head *net_exit_list)
|
|
{
|
|
synchronize_rcu();
|
|
}
|
|
|
|
static struct pernet_operations nfnl_queue_net_ops = {
|
|
.init = nfnl_queue_net_init,
|
|
.exit = nfnl_queue_net_exit,
|
|
.exit_batch = nfnl_queue_net_exit_batch,
|
|
.id = &nfnl_queue_net_id,
|
|
.size = sizeof(struct nfnl_queue_net),
|
|
};
|
|
|
|
static int __init nfnetlink_queue_init(void)
|
|
{
|
|
int status;
|
|
|
|
status = register_pernet_subsys(&nfnl_queue_net_ops);
|
|
if (status < 0) {
|
|
pr_err("failed to register pernet ops\n");
|
|
goto out;
|
|
}
|
|
|
|
netlink_register_notifier(&nfqnl_rtnl_notifier);
|
|
status = nfnetlink_subsys_register(&nfqnl_subsys);
|
|
if (status < 0) {
|
|
pr_err("failed to create netlink socket\n");
|
|
goto cleanup_netlink_notifier;
|
|
}
|
|
|
|
status = register_netdevice_notifier(&nfqnl_dev_notifier);
|
|
if (status < 0) {
|
|
pr_err("failed to register netdevice notifier\n");
|
|
goto cleanup_netlink_subsys;
|
|
}
|
|
|
|
return status;
|
|
|
|
cleanup_netlink_subsys:
|
|
nfnetlink_subsys_unregister(&nfqnl_subsys);
|
|
cleanup_netlink_notifier:
|
|
netlink_unregister_notifier(&nfqnl_rtnl_notifier);
|
|
unregister_pernet_subsys(&nfnl_queue_net_ops);
|
|
out:
|
|
return status;
|
|
}
|
|
|
|
static void __exit nfnetlink_queue_fini(void)
|
|
{
|
|
unregister_netdevice_notifier(&nfqnl_dev_notifier);
|
|
nfnetlink_subsys_unregister(&nfqnl_subsys);
|
|
netlink_unregister_notifier(&nfqnl_rtnl_notifier);
|
|
unregister_pernet_subsys(&nfnl_queue_net_ops);
|
|
|
|
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);
|