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> |
020b4c12 HW |
13 | #include <net/dst.h> |
14 | #include <net/ipv6.h> | |
15 | #include <net/ip6_route.h> | |
3e3850e9 | 16 | #include <net/xfrm.h> |
503e4faa | 17 | #include <net/ip6_checksum.h> |
c01cd429 | 18 | #include <net/netfilter/nf_queue.h> |
020b4c12 HW |
19 | |
20 | int ip6_route_me_harder(struct sk_buff *skb) | |
21 | { | |
adf30907 | 22 | struct net *net = dev_net(skb_dst(skb)->dev); |
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 HW |
31 | }; |
32 | ||
4c9483b2 | 33 | dst = ip6_route_output(net, skb->sk, &fl6); |
020b4c12 | 34 | if (dst->error) { |
eef9d90d | 35 | IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); |
64ce2073 | 36 | LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n"); |
020b4c12 | 37 | dst_release(dst); |
58e35d14 | 38 | return dst->error; |
020b4c12 HW |
39 | } |
40 | ||
41 | /* Drop old route. */ | |
adf30907 | 42 | skb_dst_drop(skb); |
020b4c12 | 43 | |
adf30907 | 44 | skb_dst_set(skb, dst); |
90348e0e UW |
45 | |
46 | #ifdef CONFIG_XFRM | |
47 | if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && | |
4c9483b2 | 48 | xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) { |
90348e0e | 49 | skb_dst_set(skb, NULL); |
4c9483b2 | 50 | dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0); |
452edd59 | 51 | if (IS_ERR(dst)) |
58e35d14 | 52 | return PTR_ERR(dst); |
90348e0e UW |
53 | skb_dst_set(skb, dst); |
54 | } | |
55 | #endif | |
56 | ||
0ad352cb PM |
57 | /* Change in oif may mean change in hh_len. */ |
58 | hh_len = skb_dst(skb)->dev->hard_header_len; | |
59 | if (skb_headroom(skb) < hh_len && | |
60 | pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)), | |
61 | 0, GFP_ATOMIC)) | |
58e35d14 | 62 | return -ENOMEM; |
0ad352cb | 63 | |
020b4c12 HW |
64 | return 0; |
65 | } | |
66 | EXPORT_SYMBOL(ip6_route_me_harder); | |
67 | ||
2cc7d573 HW |
68 | /* |
69 | * Extra routing may needed on local out, as the QUEUE target never | |
70 | * returns control to the table. | |
71 | */ | |
72 | ||
73 | struct ip6_rt_info { | |
74 | struct in6_addr daddr; | |
75 | struct in6_addr saddr; | |
9f40ac71 | 76 | u_int32_t mark; |
2cc7d573 HW |
77 | }; |
78 | ||
02f014d8 PM |
79 | static void nf_ip6_saveroute(const struct sk_buff *skb, |
80 | struct nf_queue_entry *entry) | |
2cc7d573 | 81 | { |
02f014d8 | 82 | struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); |
2cc7d573 | 83 | |
02f014d8 | 84 | if (entry->hook == NF_INET_LOCAL_OUT) { |
b71d1d42 | 85 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
2cc7d573 HW |
86 | |
87 | rt_info->daddr = iph->daddr; | |
88 | rt_info->saddr = iph->saddr; | |
9f40ac71 | 89 | rt_info->mark = skb->mark; |
2cc7d573 HW |
90 | } |
91 | } | |
92 | ||
02f014d8 PM |
93 | static int nf_ip6_reroute(struct sk_buff *skb, |
94 | const struct nf_queue_entry *entry) | |
2cc7d573 | 95 | { |
02f014d8 | 96 | struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); |
2cc7d573 | 97 | |
02f014d8 | 98 | if (entry->hook == NF_INET_LOCAL_OUT) { |
b71d1d42 | 99 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
2cc7d573 | 100 | if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) || |
9f40ac71 EL |
101 | !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) || |
102 | skb->mark != rt_info->mark) | |
3db05fea | 103 | return ip6_route_me_harder(skb); |
2cc7d573 HW |
104 | } |
105 | return 0; | |
106 | } | |
107 | ||
31ad3dd6 | 108 | static int nf_ip6_route(struct net *net, struct dst_entry **dst, |
0fae2e77 | 109 | struct flowi *fl, bool strict) |
1841a4c7 | 110 | { |
0fae2e77 FW |
111 | static const struct ipv6_pinfo fake_pinfo; |
112 | static const struct inet_sock fake_sk = { | |
113 | /* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */ | |
114 | .sk.sk_bound_dev_if = 1, | |
115 | .pinet6 = (struct ipv6_pinfo *) &fake_pinfo, | |
116 | }; | |
117 | const void *sk = strict ? &fake_sk : NULL; | |
2dad81ad FW |
118 | struct dst_entry *result; |
119 | int err; | |
120 | ||
121 | result = ip6_route_output(net, sk, &fl->u.ip6); | |
122 | err = result->error; | |
123 | if (err) | |
124 | dst_release(result); | |
125 | else | |
126 | *dst = result; | |
127 | return err; | |
1841a4c7 PM |
128 | } |
129 | ||
b51655b9 | 130 | __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, |
422c346f PM |
131 | unsigned int dataoff, u_int8_t protocol) |
132 | { | |
b71d1d42 | 133 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
b51655b9 | 134 | __sum16 csum = 0; |
422c346f PM |
135 | |
136 | switch (skb->ip_summed) { | |
84fa7933 | 137 | case CHECKSUM_COMPLETE: |
6e23ae2a | 138 | if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) |
422c346f PM |
139 | break; |
140 | if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, | |
1ab1457c | 141 | skb->len - dataoff, protocol, |
422c346f PM |
142 | csum_sub(skb->csum, |
143 | skb_checksum(skb, 0, | |
144 | dataoff, 0)))) { | |
145 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
146 | break; | |
147 | } | |
148 | /* fall through */ | |
149 | case CHECKSUM_NONE: | |
868c86bc AV |
150 | skb->csum = ~csum_unfold( |
151 | csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, | |
422c346f PM |
152 | skb->len - dataoff, |
153 | protocol, | |
154 | csum_sub(0, | |
155 | skb_checksum(skb, 0, | |
1ab1457c | 156 | dataoff, 0)))); |
422c346f PM |
157 | csum = __skb_checksum_complete(skb); |
158 | } | |
159 | return csum; | |
160 | } | |
422c346f PM |
161 | EXPORT_SYMBOL(nf_ip6_checksum); |
162 | ||
d63a6507 PM |
163 | static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook, |
164 | unsigned int dataoff, unsigned int len, | |
165 | u_int8_t protocol) | |
166 | { | |
b71d1d42 | 167 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
d63a6507 PM |
168 | __wsum hsum; |
169 | __sum16 csum = 0; | |
170 | ||
171 | switch (skb->ip_summed) { | |
172 | case CHECKSUM_COMPLETE: | |
173 | if (len == skb->len - dataoff) | |
174 | return nf_ip6_checksum(skb, hook, dataoff, protocol); | |
175 | /* fall through */ | |
176 | case CHECKSUM_NONE: | |
177 | hsum = skb_checksum(skb, 0, dataoff, 0); | |
178 | skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr, | |
179 | &ip6h->daddr, | |
180 | skb->len - dataoff, | |
181 | protocol, | |
182 | csum_sub(0, hsum))); | |
183 | skb->ip_summed = CHECKSUM_NONE; | |
c86ee67c | 184 | return __skb_checksum_complete_head(skb, dataoff + len); |
d63a6507 PM |
185 | } |
186 | return csum; | |
187 | }; | |
188 | ||
1e796fda | 189 | static const struct nf_afinfo nf_ip6_afinfo = { |
d63a6507 PM |
190 | .family = AF_INET6, |
191 | .checksum = nf_ip6_checksum, | |
192 | .checksum_partial = nf_ip6_checksum_partial, | |
193 | .route = nf_ip6_route, | |
194 | .saveroute = nf_ip6_saveroute, | |
195 | .reroute = nf_ip6_reroute, | |
196 | .route_key_size = sizeof(struct ip6_rt_info), | |
2cc7d573 HW |
197 | }; |
198 | ||
199 | int __init ipv6_netfilter_init(void) | |
200 | { | |
bce8032e | 201 | return nf_register_afinfo(&nf_ip6_afinfo); |
2cc7d573 HW |
202 | } |
203 | ||
5bf887f2 DM |
204 | /* This can be called from inet6_init() on errors, so it cannot |
205 | * be marked __exit. -DaveM | |
206 | */ | |
207 | void ipv6_netfilter_fini(void) | |
2cc7d573 | 208 | { |
bce8032e | 209 | nf_unregister_afinfo(&nf_ip6_afinfo); |
2cc7d573 | 210 | } |