2 * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/netdevice.h>
12 #include <net/netfilter/nf_tables.h>
14 #include <linux/ipv6.h>
15 #include <net/netfilter/nf_tables_ipv4.h>
16 #include <net/netfilter/nf_tables_ipv6.h>
19 nft_netdev_set_pktinfo_ipv4(struct nft_pktinfo *pkt,
21 const struct nf_hook_state *state)
23 struct iphdr *iph, _iph;
26 nft_set_pktinfo(pkt, skb, state);
28 iph = skb_header_pointer(skb, skb_network_offset(skb), sizeof(*iph),
34 if (iph->ihl < 5 || iph->version != 4)
37 len = ntohs(iph->tot_len);
44 pkt->tprot = iph->protocol;
45 pkt->xt.thoff = thoff;
46 pkt->xt.fragoff = ntohs(iph->frag_off) & IP_OFFSET;
50 __nft_netdev_set_pktinfo_ipv6(struct nft_pktinfo *pkt,
52 const struct nf_hook_state *state)
54 #if IS_ENABLED(CONFIG_IPV6)
55 struct ipv6hdr *ip6h, _ip6h;
56 unsigned int thoff = 0;
57 unsigned short frag_off;
61 ip6h = skb_header_pointer(skb, skb_network_offset(skb), sizeof(*ip6h),
66 if (ip6h->version != 6)
69 pkt_len = ntohs(ip6h->payload_len);
70 if (pkt_len + sizeof(*ip6h) > skb->len)
73 protohdr = ipv6_find_hdr(pkt->skb, &thoff, -1, &frag_off, NULL);
77 pkt->tprot = protohdr;
78 pkt->xt.thoff = thoff;
79 pkt->xt.fragoff = frag_off;
83 static inline void nft_netdev_set_pktinfo_ipv6(struct nft_pktinfo *pkt,
85 const struct nf_hook_state *state)
87 nft_set_pktinfo(pkt, skb, state);
88 __nft_netdev_set_pktinfo_ipv6(pkt, skb, state);
92 nft_do_chain_netdev(void *priv, struct sk_buff *skb,
93 const struct nf_hook_state *state)
95 struct nft_pktinfo pkt;
97 switch (skb->protocol) {
99 nft_netdev_set_pktinfo_ipv4(&pkt, skb, state);
101 case htons(ETH_P_IPV6):
102 nft_netdev_set_pktinfo_ipv6(&pkt, skb, state);
105 nft_set_pktinfo(&pkt, skb, state);
109 return nft_do_chain(&pkt, priv);
112 static struct nft_af_info nft_af_netdev __read_mostly = {
113 .family = NFPROTO_NETDEV,
114 .nhooks = NF_NETDEV_NUMHOOKS,
115 .owner = THIS_MODULE,
116 .flags = NFT_AF_NEEDS_DEV,
119 [NF_NETDEV_INGRESS] = nft_do_chain_netdev,
123 static int nf_tables_netdev_init_net(struct net *net)
125 net->nft.netdev = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
126 if (net->nft.netdev == NULL)
129 memcpy(net->nft.netdev, &nft_af_netdev, sizeof(nft_af_netdev));
131 if (nft_register_afinfo(net, net->nft.netdev) < 0)
136 kfree(net->nft.netdev);
140 static void nf_tables_netdev_exit_net(struct net *net)
142 nft_unregister_afinfo(net->nft.netdev);
143 kfree(net->nft.netdev);
146 static struct pernet_operations nf_tables_netdev_net_ops = {
147 .init = nf_tables_netdev_init_net,
148 .exit = nf_tables_netdev_exit_net,
151 static const struct nf_chain_type nft_filter_chain_netdev = {
153 .type = NFT_CHAIN_T_DEFAULT,
154 .family = NFPROTO_NETDEV,
155 .owner = THIS_MODULE,
156 .hook_mask = (1 << NF_NETDEV_INGRESS),
159 static void nft_netdev_event(unsigned long event, struct nft_af_info *afi,
160 struct net_device *dev, struct nft_table *table,
161 struct nft_base_chain *basechain)
164 case NETDEV_REGISTER:
165 if (strcmp(basechain->dev_name, dev->name) != 0)
168 BUG_ON(!(basechain->flags & NFT_BASECHAIN_DISABLED));
171 basechain->ops[0].dev = dev;
172 basechain->flags &= ~NFT_BASECHAIN_DISABLED;
173 if (!(table->flags & NFT_TABLE_F_DORMANT))
174 nft_register_basechain(basechain, afi->nops);
176 case NETDEV_UNREGISTER:
177 if (strcmp(basechain->dev_name, dev->name) != 0)
180 BUG_ON(basechain->flags & NFT_BASECHAIN_DISABLED);
182 if (!(table->flags & NFT_TABLE_F_DORMANT))
183 nft_unregister_basechain(basechain, afi->nops);
185 dev_put(basechain->ops[0].dev);
186 basechain->ops[0].dev = NULL;
187 basechain->flags |= NFT_BASECHAIN_DISABLED;
189 case NETDEV_CHANGENAME:
190 if (dev->ifindex != basechain->ops[0].dev->ifindex)
193 strncpy(basechain->dev_name, dev->name, IFNAMSIZ);
198 static int nf_tables_netdev_event(struct notifier_block *this,
199 unsigned long event, void *ptr)
201 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
202 struct nft_af_info *afi;
203 struct nft_table *table;
204 struct nft_chain *chain;
206 nfnl_lock(NFNL_SUBSYS_NFTABLES);
207 list_for_each_entry(afi, &dev_net(dev)->nft.af_info, list) {
208 if (afi->family != NFPROTO_NETDEV)
211 list_for_each_entry(table, &afi->tables, list) {
212 list_for_each_entry(chain, &table->chains, list) {
213 if (!(chain->flags & NFT_BASE_CHAIN))
216 nft_netdev_event(event, afi, dev, table,
217 nft_base_chain(chain));
221 nfnl_unlock(NFNL_SUBSYS_NFTABLES);
226 static struct notifier_block nf_tables_netdev_notifier = {
227 .notifier_call = nf_tables_netdev_event,
230 static int __init nf_tables_netdev_init(void)
234 nft_register_chain_type(&nft_filter_chain_netdev);
235 ret = register_pernet_subsys(&nf_tables_netdev_net_ops);
237 nft_unregister_chain_type(&nft_filter_chain_netdev);
239 register_netdevice_notifier(&nf_tables_netdev_notifier);
244 static void __exit nf_tables_netdev_exit(void)
246 unregister_netdevice_notifier(&nf_tables_netdev_notifier);
247 unregister_pernet_subsys(&nf_tables_netdev_net_ops);
248 nft_unregister_chain_type(&nft_filter_chain_netdev);
251 module_init(nf_tables_netdev_init);
252 module_exit(nf_tables_netdev_exit);
254 MODULE_LICENSE("GPL");
255 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
256 MODULE_ALIAS_NFT_FAMILY(5); /* NFPROTO_NETDEV */