Commit | Line | Data |
---|---|---|
f229f6ce PM |
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 | */ | |
020b4c12 | 7 | #include <linux/kernel.h> |
bb94aa16 | 8 | #include <linux/init.h> |
020b4c12 | 9 | #include <linux/ipv6.h> |
2cc7d573 HW |
10 | #include <linux/netfilter.h> |
11 | #include <linux/netfilter_ipv6.h> | |
bc3b2d7f | 12 | #include <linux/export.h> |
2a7851bf | 13 | #include <net/addrconf.h> |
020b4c12 HW |
14 | #include <net/dst.h> |
15 | #include <net/ipv6.h> | |
16 | #include <net/ip6_route.h> | |
3e3850e9 | 17 | #include <net/xfrm.h> |
503e4faa | 18 | #include <net/ip6_checksum.h> |
c01cd429 | 19 | #include <net/netfilter/nf_queue.h> |
020b4c12 | 20 | |
5f5d74d7 | 21 | int ip6_route_me_harder(struct net *net, struct sk_buff *skb) |
020b4c12 | 22 | { |
b71d1d42 | 23 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
0ad352cb | 24 | unsigned int hh_len; |
020b4c12 | 25 | struct dst_entry *dst; |
4c9483b2 DM |
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, | |
020b4c12 | 31 | }; |
a8951d58 | 32 | int err; |
020b4c12 | 33 | |
4c9483b2 | 34 | dst = ip6_route_output(net, skb->sk, &fl6); |
a8951d58 SP |
35 | err = dst->error; |
36 | if (err) { | |
eef9d90d | 37 | IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); |
ba7a46f1 | 38 | net_dbg_ratelimited("ip6_route_me_harder: No more route\n"); |
020b4c12 | 39 | dst_release(dst); |
a8951d58 | 40 | return err; |
020b4c12 HW |
41 | } |
42 | ||
43 | /* Drop old route. */ | |
adf30907 | 44 | skb_dst_drop(skb); |
020b4c12 | 45 | |
adf30907 | 46 | skb_dst_set(skb, dst); |
90348e0e UW |
47 | |
48 | #ifdef CONFIG_XFRM | |
49 | if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && | |
4c9483b2 | 50 | xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) { |
90348e0e | 51 | skb_dst_set(skb, NULL); |
4c9483b2 | 52 | dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0); |
452edd59 | 53 | if (IS_ERR(dst)) |
58e35d14 | 54 | return PTR_ERR(dst); |
90348e0e UW |
55 | skb_dst_set(skb, dst); |
56 | } | |
57 | #endif | |
58 | ||
0ad352cb PM |
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)) | |
58e35d14 | 64 | return -ENOMEM; |
0ad352cb | 65 | |
020b4c12 HW |
66 | return 0; |
67 | } | |
68 | EXPORT_SYMBOL(ip6_route_me_harder); | |
69 | ||
2cc7d573 HW |
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; | |
9f40ac71 | 78 | u_int32_t mark; |
2cc7d573 HW |
79 | }; |
80 | ||
02f014d8 PM |
81 | static void nf_ip6_saveroute(const struct sk_buff *skb, |
82 | struct nf_queue_entry *entry) | |
2cc7d573 | 83 | { |
02f014d8 | 84 | struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); |
2cc7d573 | 85 | |
1d1de89b | 86 | if (entry->state.hook == NF_INET_LOCAL_OUT) { |
b71d1d42 | 87 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
2cc7d573 HW |
88 | |
89 | rt_info->daddr = iph->daddr; | |
90 | rt_info->saddr = iph->saddr; | |
9f40ac71 | 91 | rt_info->mark = skb->mark; |
2cc7d573 HW |
92 | } |
93 | } | |
94 | ||
d815d90b | 95 | static int nf_ip6_reroute(struct net *net, struct sk_buff *skb, |
02f014d8 | 96 | const struct nf_queue_entry *entry) |
2cc7d573 | 97 | { |
02f014d8 | 98 | struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); |
2cc7d573 | 99 | |
1d1de89b | 100 | if (entry->state.hook == NF_INET_LOCAL_OUT) { |
b71d1d42 | 101 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
2cc7d573 | 102 | if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) || |
9f40ac71 EL |
103 | !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) || |
104 | skb->mark != rt_info->mark) | |
5f5d74d7 | 105 | return ip6_route_me_harder(net, skb); |
2cc7d573 HW |
106 | } |
107 | return 0; | |
108 | } | |
109 | ||
31ad3dd6 | 110 | static int nf_ip6_route(struct net *net, struct dst_entry **dst, |
0fae2e77 | 111 | struct flowi *fl, bool strict) |
1841a4c7 | 112 | { |
0fae2e77 FW |
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; | |
2dad81ad FW |
120 | struct dst_entry *result; |
121 | int err; | |
122 | ||
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; | |
1841a4c7 PM |
130 | } |
131 | ||
b51655b9 | 132 | __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, |
422c346f PM |
133 | unsigned int dataoff, u_int8_t protocol) |
134 | { | |
b71d1d42 | 135 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
b51655b9 | 136 | __sum16 csum = 0; |
422c346f PM |
137 | |
138 | switch (skb->ip_summed) { | |
84fa7933 | 139 | case CHECKSUM_COMPLETE: |
6e23ae2a | 140 | if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) |
422c346f PM |
141 | break; |
142 | if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, | |
1ab1457c | 143 | skb->len - dataoff, protocol, |
422c346f PM |
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: | |
868c86bc AV |
152 | skb->csum = ~csum_unfold( |
153 | csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, | |
422c346f PM |
154 | skb->len - dataoff, |
155 | protocol, | |
156 | csum_sub(0, | |
157 | skb_checksum(skb, 0, | |
1ab1457c | 158 | dataoff, 0)))); |
422c346f PM |
159 | csum = __skb_checksum_complete(skb); |
160 | } | |
161 | return csum; | |
162 | } | |
422c346f PM |
163 | EXPORT_SYMBOL(nf_ip6_checksum); |
164 | ||
d63a6507 PM |
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 | { | |
b71d1d42 | 169 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
d63a6507 PM |
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; | |
c86ee67c | 186 | return __skb_checksum_complete_head(skb, dataoff + len); |
d63a6507 PM |
187 | } |
188 | return csum; | |
189 | }; | |
190 | ||
2a7851bf FW |
191 | static const struct nf_ipv6_ops ipv6ops = { |
192 | .chk_addr = ipv6_chk_addr, | |
efb6de9b BT |
193 | .route_input = ip6_route_input, |
194 | .fragment = ip6_fragment | |
2a7851bf FW |
195 | }; |
196 | ||
1e796fda | 197 | static const struct nf_afinfo nf_ip6_afinfo = { |
d63a6507 PM |
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), | |
2cc7d573 HW |
205 | }; |
206 | ||
207 | int __init ipv6_netfilter_init(void) | |
208 | { | |
2a7851bf | 209 | RCU_INIT_POINTER(nf_ipv6_ops, &ipv6ops); |
bce8032e | 210 | return nf_register_afinfo(&nf_ip6_afinfo); |
2cc7d573 HW |
211 | } |
212 | ||
5bf887f2 DM |
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) | |
2cc7d573 | 217 | { |
2a7851bf | 218 | RCU_INIT_POINTER(nf_ipv6_ops, NULL); |
bce8032e | 219 | nf_unregister_afinfo(&nf_ip6_afinfo); |
2cc7d573 | 220 | } |