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@@ -0,0 +1,183 @@
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+/*
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+ * Copyright (c) 2015 Pablo Neira Ayuso <pablo@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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+#include <linux/init.h>
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+#include <linux/module.h>
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+#include <net/netfilter/nf_tables.h>
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+#include <linux/ip.h>
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+#include <linux/ipv6.h>
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+#include <net/netfilter/nf_tables_ipv4.h>
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+#include <net/netfilter/nf_tables_ipv6.h>
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+
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+static inline void
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+nft_netdev_set_pktinfo_ipv4(struct nft_pktinfo *pkt,
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+ const struct nf_hook_ops *ops, struct sk_buff *skb,
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+ const struct nf_hook_state *state)
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+{
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+ struct iphdr *iph, _iph;
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+ u32 len, thoff;
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+
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+ nft_set_pktinfo(pkt, ops, skb, state);
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+
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+ iph = skb_header_pointer(skb, skb_network_offset(skb), sizeof(*iph),
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+ &_iph);
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+ if (!iph)
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+ return;
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+
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+ iph = ip_hdr(skb);
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+ if (iph->ihl < 5 || iph->version != 4)
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+ return;
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+
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+ len = ntohs(iph->tot_len);
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+ thoff = iph->ihl * 4;
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+ if (skb->len < len)
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+ return;
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+ else if (len < thoff)
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+ return;
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+
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+ pkt->tprot = iph->protocol;
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+ pkt->xt.thoff = thoff;
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+ pkt->xt.fragoff = ntohs(iph->frag_off) & IP_OFFSET;
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+}
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+
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+static inline void
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+__nft_netdev_set_pktinfo_ipv6(struct nft_pktinfo *pkt,
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+ const struct nf_hook_ops *ops,
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+ struct sk_buff *skb,
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+ const struct nf_hook_state *state)
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+{
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+#if IS_ENABLED(CONFIG_IPV6)
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+ struct ipv6hdr *ip6h, _ip6h;
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+ unsigned int thoff = 0;
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+ unsigned short frag_off;
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+ int protohdr;
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+ u32 pkt_len;
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+
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+ ip6h = skb_header_pointer(skb, skb_network_offset(skb), sizeof(*ip6h),
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+ &_ip6h);
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+ if (!ip6h)
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+ return;
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+
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+ if (ip6h->version != 6)
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+ return;
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+
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+ pkt_len = ntohs(ip6h->payload_len);
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+ if (pkt_len + sizeof(*ip6h) > skb->len)
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+ return;
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+
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+ protohdr = ipv6_find_hdr(pkt->skb, &thoff, -1, &frag_off, NULL);
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+ if (protohdr < 0)
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+ return;
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+
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+ pkt->tprot = protohdr;
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+ pkt->xt.thoff = thoff;
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+ pkt->xt.fragoff = frag_off;
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+#endif
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+}
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+
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+static inline void nft_netdev_set_pktinfo_ipv6(struct nft_pktinfo *pkt,
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+ const struct nf_hook_ops *ops,
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+ struct sk_buff *skb,
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+ const struct nf_hook_state *state)
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+{
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+ nft_set_pktinfo(pkt, ops, skb, state);
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+ __nft_netdev_set_pktinfo_ipv6(pkt, ops, skb, state);
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+}
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+
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+static unsigned int
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+nft_do_chain_netdev(const struct nf_hook_ops *ops, struct sk_buff *skb,
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+ const struct nf_hook_state *state)
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+{
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+ struct nft_pktinfo pkt;
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+
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+ switch (eth_hdr(skb)->h_proto) {
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+ case htons(ETH_P_IP):
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+ nft_netdev_set_pktinfo_ipv4(&pkt, ops, skb, state);
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+ break;
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+ case htons(ETH_P_IPV6):
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+ nft_netdev_set_pktinfo_ipv6(&pkt, ops, skb, state);
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+ break;
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+ default:
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+ nft_set_pktinfo(&pkt, ops, skb, state);
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+ break;
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+ }
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+
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+ return nft_do_chain(&pkt, ops);
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+}
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+
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+static struct nft_af_info nft_af_netdev __read_mostly = {
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+ .family = NFPROTO_NETDEV,
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+ .nhooks = NF_NETDEV_NUMHOOKS,
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+ .owner = THIS_MODULE,
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+ .flags = NFT_AF_NEEDS_DEV,
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+ .nops = 1,
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+ .hooks = {
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+ [NF_NETDEV_INGRESS] = nft_do_chain_netdev,
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+ },
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+};
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+
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+static int nf_tables_netdev_init_net(struct net *net)
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+{
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+ net->nft.netdev = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
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+ if (net->nft.netdev == NULL)
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+ return -ENOMEM;
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+
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+ memcpy(net->nft.netdev, &nft_af_netdev, sizeof(nft_af_netdev));
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+
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+ if (nft_register_afinfo(net, net->nft.netdev) < 0)
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+ goto err;
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+
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+ return 0;
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+err:
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+ kfree(net->nft.netdev);
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+ return -ENOMEM;
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+}
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+
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+static void nf_tables_netdev_exit_net(struct net *net)
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+{
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+ nft_unregister_afinfo(net->nft.netdev);
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+ kfree(net->nft.netdev);
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+}
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+
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+static struct pernet_operations nf_tables_netdev_net_ops = {
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+ .init = nf_tables_netdev_init_net,
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+ .exit = nf_tables_netdev_exit_net,
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+};
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+
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+static const struct nf_chain_type nft_filter_chain_netdev = {
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+ .name = "filter",
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+ .type = NFT_CHAIN_T_DEFAULT,
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+ .family = NFPROTO_NETDEV,
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+ .owner = THIS_MODULE,
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+ .hook_mask = (1 << NF_NETDEV_INGRESS),
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+};
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+
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+static int __init nf_tables_netdev_init(void)
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+{
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+ int ret;
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+
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+ nft_register_chain_type(&nft_filter_chain_netdev);
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+ ret = register_pernet_subsys(&nf_tables_netdev_net_ops);
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+ if (ret < 0)
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+ nft_unregister_chain_type(&nft_filter_chain_netdev);
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+
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+ return ret;
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+}
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+
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+static void __exit nf_tables_netdev_exit(void)
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+{
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+ unregister_pernet_subsys(&nf_tables_netdev_net_ops);
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+ nft_unregister_chain_type(&nft_filter_chain_netdev);
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+}
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+
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+module_init(nf_tables_netdev_init);
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+module_exit(nf_tables_netdev_exit);
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+
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+MODULE_LICENSE("GPL");
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+MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
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+MODULE_ALIAS_NFT_FAMILY(5); /* NFPROTO_NETDEV */
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David S. Miller