Patrick McHardy | f229f6c | 2013-04-06 15:24:29 +0200 | [diff] [blame] | 1 | /* |
| 2 | * IPv6 specific functions of netfilter core |
| 3 | * |
| 4 | * Rusty Russell (C) 2000 -- This code is GPL. |
| 5 | * Patrick McHardy (C) 2006-2012 |
| 6 | */ |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 7 | #include <linux/kernel.h> |
Patrick McHardy | bb94aa1 | 2006-01-09 16:43:13 -0800 | [diff] [blame] | 8 | #include <linux/init.h> |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 9 | #include <linux/ipv6.h> |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 10 | #include <linux/netfilter.h> |
| 11 | #include <linux/netfilter_ipv6.h> |
Paul Gortmaker | bc3b2d7 | 2011-07-15 11:47:34 -0400 | [diff] [blame] | 12 | #include <linux/export.h> |
Florian Westphal | 2a7851b | 2013-05-17 03:56:10 +0000 | [diff] [blame] | 13 | #include <net/addrconf.h> |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 14 | #include <net/dst.h> |
| 15 | #include <net/ipv6.h> |
| 16 | #include <net/ip6_route.h> |
Patrick McHardy | 3e3850e | 2006-01-06 23:04:54 -0800 | [diff] [blame] | 17 | #include <net/xfrm.h> |
Brian Haley | 503e4fa | 2006-04-07 15:00:06 -0700 | [diff] [blame] | 18 | #include <net/ip6_checksum.h> |
Patrick McHardy | c01cd42 | 2007-12-05 01:24:48 -0800 | [diff] [blame] | 19 | #include <net/netfilter/nf_queue.h> |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 20 | |
Eric W. Biederman | 5f5d74d | 2015-09-25 15:07:31 -0500 | [diff] [blame] | 21 | int ip6_route_me_harder(struct net *net, struct sk_buff *skb) |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 22 | { |
Eric Dumazet | b71d1d4 | 2011-04-22 04:53:02 +0000 | [diff] [blame] | 23 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
Patrick McHardy | 0ad352c | 2012-08-26 19:14:08 +0200 | [diff] [blame] | 24 | unsigned int hh_len; |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 25 | struct dst_entry *dst; |
David S. Miller | 4c9483b | 2011-03-12 16:22:43 -0500 | [diff] [blame] | 26 | struct flowi6 fl6 = { |
| 27 | .flowi6_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0, |
| 28 | .flowi6_mark = skb->mark, |
| 29 | .daddr = iph->daddr, |
| 30 | .saddr = iph->saddr, |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 31 | }; |
Sergey Popovich | a8951d5 | 2014-05-08 16:22:35 +0300 | [diff] [blame] | 32 | int err; |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 33 | |
David S. Miller | 4c9483b | 2011-03-12 16:22:43 -0500 | [diff] [blame] | 34 | dst = ip6_route_output(net, skb->sk, &fl6); |
Sergey Popovich | a8951d5 | 2014-05-08 16:22:35 +0300 | [diff] [blame] | 35 | err = dst->error; |
| 36 | if (err) { |
Alexey Dobriyan | eef9d90 | 2008-10-14 22:55:21 -0700 | [diff] [blame] | 37 | IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); |
Joe Perches | ba7a46f | 2014-11-11 10:59:17 -0800 | [diff] [blame] | 38 | net_dbg_ratelimited("ip6_route_me_harder: No more route\n"); |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 39 | dst_release(dst); |
Sergey Popovich | a8951d5 | 2014-05-08 16:22:35 +0300 | [diff] [blame] | 40 | return err; |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 41 | } |
| 42 | |
| 43 | /* Drop old route. */ |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 44 | skb_dst_drop(skb); |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 45 | |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 46 | skb_dst_set(skb, dst); |
Ulrich Weber | 90348e0 | 2010-04-15 12:37:18 +0200 | [diff] [blame] | 47 | |
| 48 | #ifdef CONFIG_XFRM |
| 49 | if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && |
David S. Miller | 4c9483b | 2011-03-12 16:22:43 -0500 | [diff] [blame] | 50 | xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) { |
Ulrich Weber | 90348e0 | 2010-04-15 12:37:18 +0200 | [diff] [blame] | 51 | skb_dst_set(skb, NULL); |
David S. Miller | 4c9483b | 2011-03-12 16:22:43 -0500 | [diff] [blame] | 52 | dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0); |
David S. Miller | 452edd5 | 2011-03-02 13:27:41 -0800 | [diff] [blame] | 53 | if (IS_ERR(dst)) |
Patrick McHardy | 58e35d1 | 2013-04-05 06:41:11 +0000 | [diff] [blame] | 54 | return PTR_ERR(dst); |
Ulrich Weber | 90348e0 | 2010-04-15 12:37:18 +0200 | [diff] [blame] | 55 | skb_dst_set(skb, dst); |
| 56 | } |
| 57 | #endif |
| 58 | |
Patrick McHardy | 0ad352c | 2012-08-26 19:14:08 +0200 | [diff] [blame] | 59 | /* Change in oif may mean change in hh_len. */ |
| 60 | hh_len = skb_dst(skb)->dev->hard_header_len; |
| 61 | if (skb_headroom(skb) < hh_len && |
| 62 | pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)), |
| 63 | 0, GFP_ATOMIC)) |
Patrick McHardy | 58e35d1 | 2013-04-05 06:41:11 +0000 | [diff] [blame] | 64 | return -ENOMEM; |
Patrick McHardy | 0ad352c | 2012-08-26 19:14:08 +0200 | [diff] [blame] | 65 | |
Harald Welte | 020b4c1 | 2005-08-09 19:39:00 -0700 | [diff] [blame] | 66 | return 0; |
| 67 | } |
| 68 | EXPORT_SYMBOL(ip6_route_me_harder); |
| 69 | |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 70 | /* |
| 71 | * Extra routing may needed on local out, as the QUEUE target never |
| 72 | * returns control to the table. |
| 73 | */ |
| 74 | |
| 75 | struct ip6_rt_info { |
| 76 | struct in6_addr daddr; |
| 77 | struct in6_addr saddr; |
Eric Leblond | 9f40ac7 | 2008-11-25 12:18:11 +0100 | [diff] [blame] | 78 | u_int32_t mark; |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 79 | }; |
| 80 | |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 81 | static void nf_ip6_saveroute(const struct sk_buff *skb, |
| 82 | struct nf_queue_entry *entry) |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 83 | { |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 84 | struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 85 | |
David S. Miller | 1d1de89 | 2015-04-03 16:31:01 -0400 | [diff] [blame] | 86 | if (entry->state.hook == NF_INET_LOCAL_OUT) { |
Eric Dumazet | b71d1d4 | 2011-04-22 04:53:02 +0000 | [diff] [blame] | 87 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 88 | |
| 89 | rt_info->daddr = iph->daddr; |
| 90 | rt_info->saddr = iph->saddr; |
Eric Leblond | 9f40ac7 | 2008-11-25 12:18:11 +0100 | [diff] [blame] | 91 | rt_info->mark = skb->mark; |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 92 | } |
| 93 | } |
| 94 | |
Eric W. Biederman | d815d90 | 2015-09-25 15:07:28 -0500 | [diff] [blame] | 95 | static int nf_ip6_reroute(struct net *net, struct sk_buff *skb, |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 96 | const struct nf_queue_entry *entry) |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 97 | { |
Patrick McHardy | 02f014d | 2007-12-05 01:26:33 -0800 | [diff] [blame] | 98 | struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 99 | |
David S. Miller | 1d1de89 | 2015-04-03 16:31:01 -0400 | [diff] [blame] | 100 | if (entry->state.hook == NF_INET_LOCAL_OUT) { |
Eric Dumazet | b71d1d4 | 2011-04-22 04:53:02 +0000 | [diff] [blame] | 101 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 102 | if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) || |
Eric Leblond | 9f40ac7 | 2008-11-25 12:18:11 +0100 | [diff] [blame] | 103 | !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) || |
| 104 | skb->mark != rt_info->mark) |
Eric W. Biederman | 5f5d74d | 2015-09-25 15:07:31 -0500 | [diff] [blame] | 105 | return ip6_route_me_harder(net, skb); |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 106 | } |
| 107 | return 0; |
| 108 | } |
| 109 | |
Florian Westphal | 31ad3dd | 2011-04-04 16:56:29 +0200 | [diff] [blame] | 110 | static int nf_ip6_route(struct net *net, struct dst_entry **dst, |
Florian Westphal | 0fae2e7 | 2011-04-04 17:00:54 +0200 | [diff] [blame] | 111 | struct flowi *fl, bool strict) |
Patrick McHardy | 1841a4c | 2007-12-05 01:22:05 -0800 | [diff] [blame] | 112 | { |
Florian Westphal | 0fae2e7 | 2011-04-04 17:00:54 +0200 | [diff] [blame] | 113 | static const struct ipv6_pinfo fake_pinfo; |
| 114 | static const struct inet_sock fake_sk = { |
| 115 | /* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */ |
| 116 | .sk.sk_bound_dev_if = 1, |
| 117 | .pinet6 = (struct ipv6_pinfo *) &fake_pinfo, |
| 118 | }; |
| 119 | const void *sk = strict ? &fake_sk : NULL; |
Florian Westphal | 2dad81a | 2011-10-19 13:23:06 +0200 | [diff] [blame] | 120 | struct dst_entry *result; |
| 121 | int err; |
Florian Westphal | 0fae2e7 | 2011-04-04 17:00:54 +0200 | [diff] [blame] | 122 | |
Florian Westphal | 2dad81a | 2011-10-19 13:23:06 +0200 | [diff] [blame] | 123 | result = ip6_route_output(net, sk, &fl->u.ip6); |
| 124 | err = result->error; |
| 125 | if (err) |
| 126 | dst_release(result); |
| 127 | else |
| 128 | *dst = result; |
| 129 | return err; |
Patrick McHardy | 1841a4c | 2007-12-05 01:22:05 -0800 | [diff] [blame] | 130 | } |
| 131 | |
Al Viro | b51655b | 2006-11-14 21:40:42 -0800 | [diff] [blame] | 132 | __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, |
Patrick McHardy | 422c346 | 2006-04-06 14:18:43 -0700 | [diff] [blame] | 133 | unsigned int dataoff, u_int8_t protocol) |
| 134 | { |
Eric Dumazet | b71d1d4 | 2011-04-22 04:53:02 +0000 | [diff] [blame] | 135 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
Al Viro | b51655b | 2006-11-14 21:40:42 -0800 | [diff] [blame] | 136 | __sum16 csum = 0; |
Patrick McHardy | 422c346 | 2006-04-06 14:18:43 -0700 | [diff] [blame] | 137 | |
| 138 | switch (skb->ip_summed) { |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 139 | case CHECKSUM_COMPLETE: |
Patrick McHardy | 6e23ae2 | 2007-11-19 18:53:30 -0800 | [diff] [blame] | 140 | if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) |
Patrick McHardy | 422c346 | 2006-04-06 14:18:43 -0700 | [diff] [blame] | 141 | break; |
| 142 | if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 143 | skb->len - dataoff, protocol, |
Patrick McHardy | 422c346 | 2006-04-06 14:18:43 -0700 | [diff] [blame] | 144 | csum_sub(skb->csum, |
| 145 | skb_checksum(skb, 0, |
| 146 | dataoff, 0)))) { |
| 147 | skb->ip_summed = CHECKSUM_UNNECESSARY; |
| 148 | break; |
| 149 | } |
| 150 | /* fall through */ |
| 151 | case CHECKSUM_NONE: |
Al Viro | 868c86b | 2006-11-14 21:35:48 -0800 | [diff] [blame] | 152 | skb->csum = ~csum_unfold( |
| 153 | csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, |
Patrick McHardy | 422c346 | 2006-04-06 14:18:43 -0700 | [diff] [blame] | 154 | skb->len - dataoff, |
| 155 | protocol, |
| 156 | csum_sub(0, |
| 157 | skb_checksum(skb, 0, |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 158 | dataoff, 0)))); |
Patrick McHardy | 422c346 | 2006-04-06 14:18:43 -0700 | [diff] [blame] | 159 | csum = __skb_checksum_complete(skb); |
| 160 | } |
| 161 | return csum; |
| 162 | } |
Patrick McHardy | 422c346 | 2006-04-06 14:18:43 -0700 | [diff] [blame] | 163 | EXPORT_SYMBOL(nf_ip6_checksum); |
| 164 | |
Patrick McHardy | d63a650 | 2008-03-20 15:15:53 +0100 | [diff] [blame] | 165 | static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook, |
| 166 | unsigned int dataoff, unsigned int len, |
| 167 | u_int8_t protocol) |
| 168 | { |
Eric Dumazet | b71d1d4 | 2011-04-22 04:53:02 +0000 | [diff] [blame] | 169 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
Patrick McHardy | d63a650 | 2008-03-20 15:15:53 +0100 | [diff] [blame] | 170 | __wsum hsum; |
| 171 | __sum16 csum = 0; |
| 172 | |
| 173 | switch (skb->ip_summed) { |
| 174 | case CHECKSUM_COMPLETE: |
| 175 | if (len == skb->len - dataoff) |
| 176 | return nf_ip6_checksum(skb, hook, dataoff, protocol); |
| 177 | /* fall through */ |
| 178 | case CHECKSUM_NONE: |
| 179 | hsum = skb_checksum(skb, 0, dataoff, 0); |
| 180 | skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr, |
| 181 | &ip6h->daddr, |
| 182 | skb->len - dataoff, |
| 183 | protocol, |
| 184 | csum_sub(0, hsum))); |
| 185 | skb->ip_summed = CHECKSUM_NONE; |
Shan Wei | c86ee67 | 2010-06-14 16:20:02 +0200 | [diff] [blame] | 186 | return __skb_checksum_complete_head(skb, dataoff + len); |
Patrick McHardy | d63a650 | 2008-03-20 15:15:53 +0100 | [diff] [blame] | 187 | } |
| 188 | return csum; |
| 189 | }; |
| 190 | |
Florian Westphal | 2a7851b | 2013-05-17 03:56:10 +0000 | [diff] [blame] | 191 | static const struct nf_ipv6_ops ipv6ops = { |
| 192 | .chk_addr = ipv6_chk_addr, |
Bernhard Thaler | efb6de9 | 2015-05-30 15:30:16 +0200 | [diff] [blame] | 193 | .route_input = ip6_route_input, |
| 194 | .fragment = ip6_fragment |
Florian Westphal | 2a7851b | 2013-05-17 03:56:10 +0000 | [diff] [blame] | 195 | }; |
| 196 | |
Patrick McHardy | 1e796fd | 2007-12-17 22:42:27 -0800 | [diff] [blame] | 197 | static const struct nf_afinfo nf_ip6_afinfo = { |
Patrick McHardy | d63a650 | 2008-03-20 15:15:53 +0100 | [diff] [blame] | 198 | .family = AF_INET6, |
| 199 | .checksum = nf_ip6_checksum, |
| 200 | .checksum_partial = nf_ip6_checksum_partial, |
| 201 | .route = nf_ip6_route, |
| 202 | .saveroute = nf_ip6_saveroute, |
| 203 | .reroute = nf_ip6_reroute, |
| 204 | .route_key_size = sizeof(struct ip6_rt_info), |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 205 | }; |
| 206 | |
| 207 | int __init ipv6_netfilter_init(void) |
| 208 | { |
Florian Westphal | 2a7851b | 2013-05-17 03:56:10 +0000 | [diff] [blame] | 209 | RCU_INIT_POINTER(nf_ipv6_ops, &ipv6ops); |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 210 | return nf_register_afinfo(&nf_ip6_afinfo); |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 211 | } |
| 212 | |
David S. Miller | 5bf887f | 2006-01-10 21:02:21 -0800 | [diff] [blame] | 213 | /* This can be called from inet6_init() on errors, so it cannot |
| 214 | * be marked __exit. -DaveM |
| 215 | */ |
| 216 | void ipv6_netfilter_fini(void) |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 217 | { |
Florian Westphal | 2a7851b | 2013-05-17 03:56:10 +0000 | [diff] [blame] | 218 | RCU_INIT_POINTER(nf_ipv6_ops, NULL); |
Patrick McHardy | bce8032 | 2006-04-06 14:18:09 -0700 | [diff] [blame] | 219 | nf_unregister_afinfo(&nf_ip6_afinfo); |
Harald Welte | 2cc7d57 | 2005-08-09 19:42:34 -0700 | [diff] [blame] | 220 | } |