Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2008 Patrick McHardy <kaber@trash.net> |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 3 | * Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org> |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License version 2 as |
| 7 | * published by the Free Software Foundation. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/list.h> |
| 13 | #include <linux/skbuff.h> |
| 14 | #include <linux/netlink.h> |
| 15 | #include <linux/netfilter.h> |
| 16 | #include <linux/netfilter_ipv4.h> |
| 17 | #include <linux/netfilter/nfnetlink.h> |
| 18 | #include <linux/netfilter/nf_tables.h> |
| 19 | #include <net/netfilter/nf_tables.h> |
Pablo Neira Ayuso | 0ca743a | 2013-10-14 00:06:06 +0200 | [diff] [blame] | 20 | #include <net/netfilter/nf_tables_ipv4.h> |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 21 | #include <net/route.h> |
| 22 | #include <net/ip.h> |
| 23 | |
Eric W. Biederman | 06198b3 | 2015-09-18 14:33:06 -0500 | [diff] [blame] | 24 | static unsigned int nf_route_table_hook(void *priv, |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 25 | struct sk_buff *skb, |
David S. Miller | 238e54c | 2015-04-03 20:32:56 -0400 | [diff] [blame] | 26 | const struct nf_hook_state *state) |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 27 | { |
| 28 | unsigned int ret; |
Pablo Neira Ayuso | 0ca743a | 2013-10-14 00:06:06 +0200 | [diff] [blame] | 29 | struct nft_pktinfo pkt; |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 30 | u32 mark; |
| 31 | __be32 saddr, daddr; |
| 32 | u_int8_t tos; |
| 33 | const struct iphdr *iph; |
Liping Zhang | d1a6cba | 2016-09-06 22:31:02 +0800 | [diff] [blame] | 34 | int err; |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 35 | |
| 36 | /* root is playing with raw sockets. */ |
| 37 | if (skb->len < sizeof(struct iphdr) || |
| 38 | ip_hdrlen(skb) < sizeof(struct iphdr)) |
| 39 | return NF_ACCEPT; |
| 40 | |
Eric W. Biederman | 6aa187f | 2015-09-18 14:32:57 -0500 | [diff] [blame] | 41 | nft_set_pktinfo_ipv4(&pkt, skb, state); |
Pablo Neira Ayuso | 0ca743a | 2013-10-14 00:06:06 +0200 | [diff] [blame] | 42 | |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 43 | mark = skb->mark; |
| 44 | iph = ip_hdr(skb); |
| 45 | saddr = iph->saddr; |
| 46 | daddr = iph->daddr; |
| 47 | tos = iph->tos; |
| 48 | |
Eric W. Biederman | 06198b3 | 2015-09-18 14:33:06 -0500 | [diff] [blame] | 49 | ret = nft_do_chain(&pkt, priv); |
Liping Zhang | d1a6cba | 2016-09-06 22:31:02 +0800 | [diff] [blame] | 50 | if (ret != NF_DROP && ret != NF_STOLEN) { |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 51 | iph = ip_hdr(skb); |
| 52 | |
| 53 | if (iph->saddr != saddr || |
| 54 | iph->daddr != daddr || |
| 55 | skb->mark != mark || |
Liping Zhang | d1a6cba | 2016-09-06 22:31:02 +0800 | [diff] [blame] | 56 | iph->tos != tos) { |
| 57 | err = ip_route_me_harder(state->net, skb, RTN_UNSPEC); |
| 58 | if (err < 0) |
| 59 | ret = NF_DROP_ERR(err); |
| 60 | } |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 61 | } |
| 62 | return ret; |
| 63 | } |
| 64 | |
Patrick McHardy | 2a37d75 | 2014-01-09 18:42:37 +0000 | [diff] [blame] | 65 | static const struct nf_chain_type nft_chain_route_ipv4 = { |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 66 | .name = "route", |
| 67 | .type = NFT_CHAIN_T_ROUTE, |
Patrick McHardy | fa2c1de | 2014-01-09 18:42:38 +0000 | [diff] [blame] | 68 | .family = NFPROTO_IPV4, |
| 69 | .owner = THIS_MODULE, |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 70 | .hook_mask = (1 << NF_INET_LOCAL_OUT), |
Patrick McHardy | fa2c1de | 2014-01-09 18:42:38 +0000 | [diff] [blame] | 71 | .hooks = { |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 72 | [NF_INET_LOCAL_OUT] = nf_route_table_hook, |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 73 | }, |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 74 | }; |
| 75 | |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 76 | static int __init nft_chain_route_init(void) |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 77 | { |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 78 | return nft_register_chain_type(&nft_chain_route_ipv4); |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 79 | } |
| 80 | |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 81 | static void __exit nft_chain_route_exit(void) |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 82 | { |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 83 | nft_unregister_chain_type(&nft_chain_route_ipv4); |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 84 | } |
| 85 | |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 86 | module_init(nft_chain_route_init); |
| 87 | module_exit(nft_chain_route_exit); |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 88 | |
| 89 | MODULE_LICENSE("GPL"); |
| 90 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |
Pablo Neira Ayuso | 9370761 | 2013-10-10 23:21:26 +0200 | [diff] [blame] | 91 | MODULE_ALIAS_NFT_CHAIN(AF_INET, "route"); |