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); |
7d98386d | 24 | struct sock *sk = sk_to_full_sk(skb->sk); |
0ad352cb | 25 | unsigned int hh_len; |
020b4c12 | 26 | struct dst_entry *dst; |
4c9483b2 | 27 | struct flowi6 fl6 = { |
7d98386d | 28 | .flowi6_oif = sk ? sk->sk_bound_dev_if : 0, |
4c9483b2 | 29 | .flowi6_mark = skb->mark, |
7d98386d | 30 | .flowi6_uid = sock_net_uid(net, sk), |
4c9483b2 DM |
31 | .daddr = iph->daddr, |
32 | .saddr = iph->saddr, | |
020b4c12 | 33 | }; |
a8951d58 | 34 | int err; |
020b4c12 | 35 | |
7d98386d | 36 | dst = ip6_route_output(net, sk, &fl6); |
a8951d58 SP |
37 | err = dst->error; |
38 | if (err) { | |
eef9d90d | 39 | IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); |
ba7a46f1 | 40 | net_dbg_ratelimited("ip6_route_me_harder: No more route\n"); |
020b4c12 | 41 | dst_release(dst); |
a8951d58 | 42 | return err; |
020b4c12 HW |
43 | } |
44 | ||
45 | /* Drop old route. */ | |
adf30907 | 46 | skb_dst_drop(skb); |
020b4c12 | 47 | |
adf30907 | 48 | skb_dst_set(skb, dst); |
90348e0e UW |
49 | |
50 | #ifdef CONFIG_XFRM | |
51 | if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && | |
4c9483b2 | 52 | xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) { |
90348e0e | 53 | skb_dst_set(skb, NULL); |
7d98386d | 54 | dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0); |
452edd59 | 55 | if (IS_ERR(dst)) |
58e35d14 | 56 | return PTR_ERR(dst); |
90348e0e UW |
57 | skb_dst_set(skb, dst); |
58 | } | |
59 | #endif | |
60 | ||
0ad352cb PM |
61 | /* Change in oif may mean change in hh_len. */ |
62 | hh_len = skb_dst(skb)->dev->hard_header_len; | |
63 | if (skb_headroom(skb) < hh_len && | |
64 | pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)), | |
65 | 0, GFP_ATOMIC)) | |
58e35d14 | 66 | return -ENOMEM; |
0ad352cb | 67 | |
020b4c12 HW |
68 | return 0; |
69 | } | |
70 | EXPORT_SYMBOL(ip6_route_me_harder); | |
71 | ||
ce388f45 | 72 | static int nf_ip6_reroute(struct sk_buff *skb, |
02f014d8 | 73 | const struct nf_queue_entry *entry) |
2cc7d573 | 74 | { |
02f014d8 | 75 | struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); |
2cc7d573 | 76 | |
1d1de89b | 77 | if (entry->state.hook == NF_INET_LOCAL_OUT) { |
b71d1d42 | 78 | const struct ipv6hdr *iph = ipv6_hdr(skb); |
2cc7d573 | 79 | if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) || |
9f40ac71 EL |
80 | !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) || |
81 | skb->mark != rt_info->mark) | |
ce388f45 | 82 | return ip6_route_me_harder(entry->state.net, skb); |
2cc7d573 HW |
83 | } |
84 | return 0; | |
85 | } | |
86 | ||
31ad3dd6 | 87 | static int nf_ip6_route(struct net *net, struct dst_entry **dst, |
0fae2e77 | 88 | struct flowi *fl, bool strict) |
1841a4c7 | 89 | { |
0fae2e77 FW |
90 | static const struct ipv6_pinfo fake_pinfo; |
91 | static const struct inet_sock fake_sk = { | |
92 | /* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */ | |
93 | .sk.sk_bound_dev_if = 1, | |
94 | .pinet6 = (struct ipv6_pinfo *) &fake_pinfo, | |
95 | }; | |
96 | const void *sk = strict ? &fake_sk : NULL; | |
2dad81ad FW |
97 | struct dst_entry *result; |
98 | int err; | |
99 | ||
100 | result = ip6_route_output(net, sk, &fl->u.ip6); | |
101 | err = result->error; | |
102 | if (err) | |
103 | dst_release(result); | |
104 | else | |
105 | *dst = result; | |
106 | return err; | |
1841a4c7 PM |
107 | } |
108 | ||
b51655b9 | 109 | __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, |
422c346f PM |
110 | unsigned int dataoff, u_int8_t protocol) |
111 | { | |
b71d1d42 | 112 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
b51655b9 | 113 | __sum16 csum = 0; |
422c346f PM |
114 | |
115 | switch (skb->ip_summed) { | |
84fa7933 | 116 | case CHECKSUM_COMPLETE: |
6e23ae2a | 117 | if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) |
422c346f PM |
118 | break; |
119 | if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, | |
1ab1457c | 120 | skb->len - dataoff, protocol, |
422c346f PM |
121 | csum_sub(skb->csum, |
122 | skb_checksum(skb, 0, | |
123 | dataoff, 0)))) { | |
124 | skb->ip_summed = CHECKSUM_UNNECESSARY; | |
125 | break; | |
126 | } | |
127 | /* fall through */ | |
128 | case CHECKSUM_NONE: | |
868c86bc AV |
129 | skb->csum = ~csum_unfold( |
130 | csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, | |
422c346f PM |
131 | skb->len - dataoff, |
132 | protocol, | |
133 | csum_sub(0, | |
134 | skb_checksum(skb, 0, | |
1ab1457c | 135 | dataoff, 0)))); |
422c346f PM |
136 | csum = __skb_checksum_complete(skb); |
137 | } | |
138 | return csum; | |
139 | } | |
422c346f PM |
140 | EXPORT_SYMBOL(nf_ip6_checksum); |
141 | ||
d63a6507 PM |
142 | static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook, |
143 | unsigned int dataoff, unsigned int len, | |
144 | u_int8_t protocol) | |
145 | { | |
b71d1d42 | 146 | const struct ipv6hdr *ip6h = ipv6_hdr(skb); |
d63a6507 PM |
147 | __wsum hsum; |
148 | __sum16 csum = 0; | |
149 | ||
150 | switch (skb->ip_summed) { | |
151 | case CHECKSUM_COMPLETE: | |
152 | if (len == skb->len - dataoff) | |
153 | return nf_ip6_checksum(skb, hook, dataoff, protocol); | |
154 | /* fall through */ | |
155 | case CHECKSUM_NONE: | |
156 | hsum = skb_checksum(skb, 0, dataoff, 0); | |
157 | skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr, | |
158 | &ip6h->daddr, | |
159 | skb->len - dataoff, | |
160 | protocol, | |
161 | csum_sub(0, hsum))); | |
162 | skb->ip_summed = CHECKSUM_NONE; | |
c86ee67c | 163 | return __skb_checksum_complete_head(skb, dataoff + len); |
d63a6507 PM |
164 | } |
165 | return csum; | |
166 | }; | |
167 | ||
2a7851bf | 168 | static const struct nf_ipv6_ops ipv6ops = { |
f7dcbe2f PNA |
169 | .chk_addr = ipv6_chk_addr, |
170 | .route_input = ip6_route_input, | |
171 | .fragment = ip6_fragment, | |
172 | .checksum = nf_ip6_checksum, | |
173 | .checksum_partial = nf_ip6_checksum_partial, | |
3f87c08c | 174 | .route = nf_ip6_route, |
ce388f45 | 175 | .reroute = nf_ip6_reroute, |
2a7851bf FW |
176 | }; |
177 | ||
2cc7d573 HW |
178 | int __init ipv6_netfilter_init(void) |
179 | { | |
2a7851bf | 180 | RCU_INIT_POINTER(nf_ipv6_ops, &ipv6ops); |
b3a61254 | 181 | return 0; |
2cc7d573 HW |
182 | } |
183 | ||
5bf887f2 DM |
184 | /* This can be called from inet6_init() on errors, so it cannot |
185 | * be marked __exit. -DaveM | |
186 | */ | |
187 | void ipv6_netfilter_fini(void) | |
2cc7d573 | 188 | { |
2a7851bf | 189 | RCU_INIT_POINTER(nf_ipv6_ops, NULL); |
2cc7d573 | 190 | } |