net: Put flowi_* prefix on AF independent members of struct flowi
[linux-3.10.git] / net / ipv6 / netfilter.c
1 #include <linux/kernel.h>
2 #include <linux/init.h>
3 #include <linux/ipv6.h>
4 #include <linux/netfilter.h>
5 #include <linux/netfilter_ipv6.h>
6 #include <net/dst.h>
7 #include <net/ipv6.h>
8 #include <net/ip6_route.h>
9 #include <net/xfrm.h>
10 #include <net/ip6_checksum.h>
11 #include <net/netfilter/nf_queue.h>
12
13 int ip6_route_me_harder(struct sk_buff *skb)
14 {
15         struct net *net = dev_net(skb_dst(skb)->dev);
16         struct ipv6hdr *iph = ipv6_hdr(skb);
17         struct dst_entry *dst;
18         struct flowi fl = {
19                 .flowi_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
20                 .flowi_mark = skb->mark,
21                 .fl6_dst = iph->daddr,
22                 .fl6_src = iph->saddr,
23         };
24
25         dst = ip6_route_output(net, skb->sk, &fl);
26         if (dst->error) {
27                 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
28                 LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n");
29                 dst_release(dst);
30                 return -EINVAL;
31         }
32
33         /* Drop old route. */
34         skb_dst_drop(skb);
35
36         skb_dst_set(skb, dst);
37
38 #ifdef CONFIG_XFRM
39         if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
40             xfrm_decode_session(skb, &fl, AF_INET6) == 0) {
41                 skb_dst_set(skb, NULL);
42                 dst = xfrm_lookup(net, dst, &fl, skb->sk, 0);
43                 if (IS_ERR(dst))
44                         return -1;
45                 skb_dst_set(skb, dst);
46         }
47 #endif
48
49         return 0;
50 }
51 EXPORT_SYMBOL(ip6_route_me_harder);
52
53 /*
54  * Extra routing may needed on local out, as the QUEUE target never
55  * returns control to the table.
56  */
57
58 struct ip6_rt_info {
59         struct in6_addr daddr;
60         struct in6_addr saddr;
61         u_int32_t mark;
62 };
63
64 static void nf_ip6_saveroute(const struct sk_buff *skb,
65                              struct nf_queue_entry *entry)
66 {
67         struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);
68
69         if (entry->hook == NF_INET_LOCAL_OUT) {
70                 struct ipv6hdr *iph = ipv6_hdr(skb);
71
72                 rt_info->daddr = iph->daddr;
73                 rt_info->saddr = iph->saddr;
74                 rt_info->mark = skb->mark;
75         }
76 }
77
78 static int nf_ip6_reroute(struct sk_buff *skb,
79                           const struct nf_queue_entry *entry)
80 {
81         struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);
82
83         if (entry->hook == NF_INET_LOCAL_OUT) {
84                 struct ipv6hdr *iph = ipv6_hdr(skb);
85                 if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
86                     !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) ||
87                     skb->mark != rt_info->mark)
88                         return ip6_route_me_harder(skb);
89         }
90         return 0;
91 }
92
93 static int nf_ip6_route(struct dst_entry **dst, struct flowi *fl)
94 {
95         *dst = ip6_route_output(&init_net, NULL, fl);
96         return (*dst)->error;
97 }
98
99 __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
100                              unsigned int dataoff, u_int8_t protocol)
101 {
102         struct ipv6hdr *ip6h = ipv6_hdr(skb);
103         __sum16 csum = 0;
104
105         switch (skb->ip_summed) {
106         case CHECKSUM_COMPLETE:
107                 if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN)
108                         break;
109                 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
110                                      skb->len - dataoff, protocol,
111                                      csum_sub(skb->csum,
112                                               skb_checksum(skb, 0,
113                                                            dataoff, 0)))) {
114                         skb->ip_summed = CHECKSUM_UNNECESSARY;
115                         break;
116                 }
117                 /* fall through */
118         case CHECKSUM_NONE:
119                 skb->csum = ~csum_unfold(
120                                 csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
121                                              skb->len - dataoff,
122                                              protocol,
123                                              csum_sub(0,
124                                                       skb_checksum(skb, 0,
125                                                                    dataoff, 0))));
126                 csum = __skb_checksum_complete(skb);
127         }
128         return csum;
129 }
130 EXPORT_SYMBOL(nf_ip6_checksum);
131
132 static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook,
133                                        unsigned int dataoff, unsigned int len,
134                                        u_int8_t protocol)
135 {
136         struct ipv6hdr *ip6h = ipv6_hdr(skb);
137         __wsum hsum;
138         __sum16 csum = 0;
139
140         switch (skb->ip_summed) {
141         case CHECKSUM_COMPLETE:
142                 if (len == skb->len - dataoff)
143                         return nf_ip6_checksum(skb, hook, dataoff, protocol);
144                 /* fall through */
145         case CHECKSUM_NONE:
146                 hsum = skb_checksum(skb, 0, dataoff, 0);
147                 skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
148                                                          &ip6h->daddr,
149                                                          skb->len - dataoff,
150                                                          protocol,
151                                                          csum_sub(0, hsum)));
152                 skb->ip_summed = CHECKSUM_NONE;
153                 return __skb_checksum_complete_head(skb, dataoff + len);
154         }
155         return csum;
156 };
157
158 static const struct nf_afinfo nf_ip6_afinfo = {
159         .family                 = AF_INET6,
160         .checksum               = nf_ip6_checksum,
161         .checksum_partial       = nf_ip6_checksum_partial,
162         .route                  = nf_ip6_route,
163         .saveroute              = nf_ip6_saveroute,
164         .reroute                = nf_ip6_reroute,
165         .route_key_size         = sizeof(struct ip6_rt_info),
166 };
167
168 int __init ipv6_netfilter_init(void)
169 {
170         return nf_register_afinfo(&nf_ip6_afinfo);
171 }
172
173 /* This can be called from inet6_init() on errors, so it cannot
174  * be marked __exit. -DaveM
175  */
176 void ipv6_netfilter_fini(void)
177 {
178         nf_unregister_afinfo(&nf_ip6_afinfo);
179 }