1 // SPDX-License-Identifier: GPL-2.0-only
2 /* (C) 1999-2001 Paul `Rusty' Russell
3 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
6 #include <linux/types.h>
7 #include <linux/ipv6.h>
9 #include <linux/netfilter.h>
10 #include <linux/module.h>
11 #include <linux/skbuff.h>
12 #include <linux/icmp.h>
13 #include <linux/sysctl.h>
14 #include <net/ipv6_frag.h>
16 #include <linux/netfilter_ipv6.h>
17 #include <linux/netfilter_bridge.h>
18 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
19 #include <net/netfilter/nf_conntrack.h>
20 #include <net/netfilter/nf_conntrack_helper.h>
21 #include <net/netfilter/nf_conntrack_l4proto.h>
22 #include <net/netfilter/nf_conntrack_core.h>
23 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
25 #include <net/netfilter/nf_conntrack_zones.h>
26 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
28 static DEFINE_MUTEX(defrag6_mutex);
30 static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
33 u16 zone_id = NF_CT_DEFAULT_ZONE_ID;
34 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
36 enum ip_conntrack_info ctinfo;
37 const struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
39 zone_id = nf_ct_zone_id(nf_ct_zone(ct), CTINFO2DIR(ctinfo));
42 if (nf_bridge_in_prerouting(skb))
43 return IP6_DEFRAG_CONNTRACK_BRIDGE_IN + zone_id;
45 if (hooknum == NF_INET_PRE_ROUTING)
46 return IP6_DEFRAG_CONNTRACK_IN + zone_id;
48 return IP6_DEFRAG_CONNTRACK_OUT + zone_id;
51 static unsigned int ipv6_defrag(void *priv,
53 const struct nf_hook_state *state)
57 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
58 /* Previously seen (loopback)? */
59 if (skb_nfct(skb) && !nf_ct_is_template((struct nf_conn *)skb_nfct(skb)))
62 if (skb->_nfct == IP_CT_UNTRACKED)
66 err = nf_ct_frag6_gather(state->net, skb,
67 nf_ct6_defrag_user(state->hook, skb));
69 if (err == -EINPROGRESS)
72 return err == 0 ? NF_ACCEPT : NF_DROP;
75 static const struct nf_hook_ops ipv6_defrag_ops[] = {
79 .hooknum = NF_INET_PRE_ROUTING,
80 .priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
85 .hooknum = NF_INET_LOCAL_OUT,
86 .priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
90 static void __net_exit defrag6_net_exit(struct net *net)
92 if (net->nf.defrag_ipv6_users) {
93 nf_unregister_net_hooks(net, ipv6_defrag_ops,
94 ARRAY_SIZE(ipv6_defrag_ops));
95 net->nf.defrag_ipv6_users = 0;
99 static struct pernet_operations defrag6_net_ops = {
100 .exit = defrag6_net_exit,
103 static int __init nf_defrag_init(void)
107 ret = nf_ct_frag6_init();
109 pr_err("nf_defrag_ipv6: can't initialize frag6.\n");
112 ret = register_pernet_subsys(&defrag6_net_ops);
114 pr_err("nf_defrag_ipv6: can't register pernet ops\n");
120 nf_ct_frag6_cleanup();
125 static void __exit nf_defrag_fini(void)
127 unregister_pernet_subsys(&defrag6_net_ops);
128 nf_ct_frag6_cleanup();
131 int nf_defrag_ipv6_enable(struct net *net)
135 mutex_lock(&defrag6_mutex);
136 if (net->nf.defrag_ipv6_users == UINT_MAX) {
141 if (net->nf.defrag_ipv6_users) {
142 net->nf.defrag_ipv6_users++;
146 err = nf_register_net_hooks(net, ipv6_defrag_ops,
147 ARRAY_SIZE(ipv6_defrag_ops));
149 net->nf.defrag_ipv6_users = 1;
152 mutex_unlock(&defrag6_mutex);
155 EXPORT_SYMBOL_GPL(nf_defrag_ipv6_enable);
157 void nf_defrag_ipv6_disable(struct net *net)
159 mutex_lock(&defrag6_mutex);
160 if (net->nf.defrag_ipv6_users) {
161 net->nf.defrag_ipv6_users--;
162 if (net->nf.defrag_ipv6_users == 0)
163 nf_unregister_net_hooks(net, ipv6_defrag_ops,
164 ARRAY_SIZE(ipv6_defrag_ops));
166 mutex_unlock(&defrag6_mutex);
168 EXPORT_SYMBOL_GPL(nf_defrag_ipv6_disable);
170 module_init(nf_defrag_init);
171 module_exit(nf_defrag_fini);
173 MODULE_LICENSE("GPL");