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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
13int ip6_route_me_harder(struct sk_buff *skb)
14{
15 struct net *net = dev_net(skb_dst(skb)->dev);
16 const struct ipv6hdr *iph = ipv6_hdr(skb);
17 struct dst_entry *dst;
18 struct flowi6 fl6 = {
19 .flowi6_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
20 .flowi6_mark = skb->mark,
21 .daddr = iph->daddr,
22 .saddr = iph->saddr,
23 };
24
25 dst = ip6_route_output(net, skb->sk, &fl6);
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, flowi6_to_flowi(&fl6), AF_INET6) == 0) {
41 skb_dst_set(skb, NULL);
42 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), 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}
51EXPORT_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
58struct ip6_rt_info {
59 struct in6_addr daddr;
60 struct in6_addr saddr;
61 u_int32_t mark;
62};
63
64static 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 const 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
78static 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 const 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
93static int nf_ip6_route(struct net *net, struct dst_entry **dst,
94 struct flowi *fl, bool strict)
95{
96 static const struct ipv6_pinfo fake_pinfo;
97 static const struct inet_sock fake_sk = {
98 /* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */
99 .sk.sk_bound_dev_if = 1,
100 .pinet6 = (struct ipv6_pinfo *) &fake_pinfo,
101 };
102 const void *sk = strict ? &fake_sk : NULL;
103
104 *dst = ip6_route_output(net, sk, &fl->u.ip6);
105 return (*dst)->error;
106}
107
108__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
109 unsigned int dataoff, u_int8_t protocol)
110{
111 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
112 __sum16 csum = 0;
113
114 switch (skb->ip_summed) {
115 case CHECKSUM_COMPLETE:
116 if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN)
117 break;
118 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
119 skb->len - dataoff, protocol,
120 csum_sub(skb->csum,
121 skb_checksum(skb, 0,
122 dataoff, 0)))) {
123 skb->ip_summed = CHECKSUM_UNNECESSARY;
124 break;
125 }
126 /* fall through */
127 case CHECKSUM_NONE:
128 skb->csum = ~csum_unfold(
129 csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
130 skb->len - dataoff,
131 protocol,
132 csum_sub(0,
133 skb_checksum(skb, 0,
134 dataoff, 0))));
135 csum = __skb_checksum_complete(skb);
136 }
137 return csum;
138}
139EXPORT_SYMBOL(nf_ip6_checksum);
140
141static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook,
142 unsigned int dataoff, unsigned int len,
143 u_int8_t protocol)
144{
145 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
146 __wsum hsum;
147 __sum16 csum = 0;
148
149 switch (skb->ip_summed) {
150 case CHECKSUM_COMPLETE:
151 if (len == skb->len - dataoff)
152 return nf_ip6_checksum(skb, hook, dataoff, protocol);
153 /* fall through */
154 case CHECKSUM_NONE:
155 hsum = skb_checksum(skb, 0, dataoff, 0);
156 skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
157 &ip6h->daddr,
158 skb->len - dataoff,
159 protocol,
160 csum_sub(0, hsum)));
161 skb->ip_summed = CHECKSUM_NONE;
162 return __skb_checksum_complete_head(skb, dataoff + len);
163 }
164 return csum;
165};
166
167static const struct nf_afinfo nf_ip6_afinfo = {
168 .family = AF_INET6,
169 .checksum = nf_ip6_checksum,
170 .checksum_partial = nf_ip6_checksum_partial,
171 .route = nf_ip6_route,
172 .saveroute = nf_ip6_saveroute,
173 .reroute = nf_ip6_reroute,
174 .route_key_size = sizeof(struct ip6_rt_info),
175};
176
177int __init ipv6_netfilter_init(void)
178{
179 return nf_register_afinfo(&nf_ip6_afinfo);
180}
181
182/* This can be called from inet6_init() on errors, so it cannot
183 * be marked __exit. -DaveM
184 */
185void ipv6_netfilter_fini(void)
186{
187 nf_unregister_afinfo(&nf_ip6_afinfo);
188}
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 <linux/export.h>
7#include <net/dst.h>
8#include <net/ipv6.h>
9#include <net/ip6_route.h>
10#include <net/xfrm.h>
11#include <net/ip6_checksum.h>
12#include <net/netfilter/nf_queue.h>
13
14int ip6_route_me_harder(struct sk_buff *skb)
15{
16 struct net *net = dev_net(skb_dst(skb)->dev);
17 const struct ipv6hdr *iph = ipv6_hdr(skb);
18 struct dst_entry *dst;
19 struct flowi6 fl6 = {
20 .flowi6_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0,
21 .flowi6_mark = skb->mark,
22 .daddr = iph->daddr,
23 .saddr = iph->saddr,
24 };
25
26 dst = ip6_route_output(net, skb->sk, &fl6);
27 if (dst->error) {
28 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
29 LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n");
30 dst_release(dst);
31 return -EINVAL;
32 }
33
34 /* Drop old route. */
35 skb_dst_drop(skb);
36
37 skb_dst_set(skb, dst);
38
39#ifdef CONFIG_XFRM
40 if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
41 xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) {
42 skb_dst_set(skb, NULL);
43 dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0);
44 if (IS_ERR(dst))
45 return -1;
46 skb_dst_set(skb, dst);
47 }
48#endif
49
50 return 0;
51}
52EXPORT_SYMBOL(ip6_route_me_harder);
53
54/*
55 * Extra routing may needed on local out, as the QUEUE target never
56 * returns control to the table.
57 */
58
59struct ip6_rt_info {
60 struct in6_addr daddr;
61 struct in6_addr saddr;
62 u_int32_t mark;
63};
64
65static void nf_ip6_saveroute(const struct sk_buff *skb,
66 struct nf_queue_entry *entry)
67{
68 struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);
69
70 if (entry->hook == NF_INET_LOCAL_OUT) {
71 const struct ipv6hdr *iph = ipv6_hdr(skb);
72
73 rt_info->daddr = iph->daddr;
74 rt_info->saddr = iph->saddr;
75 rt_info->mark = skb->mark;
76 }
77}
78
79static int nf_ip6_reroute(struct sk_buff *skb,
80 const struct nf_queue_entry *entry)
81{
82 struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry);
83
84 if (entry->hook == NF_INET_LOCAL_OUT) {
85 const struct ipv6hdr *iph = ipv6_hdr(skb);
86 if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) ||
87 !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) ||
88 skb->mark != rt_info->mark)
89 return ip6_route_me_harder(skb);
90 }
91 return 0;
92}
93
94static int nf_ip6_route(struct net *net, struct dst_entry **dst,
95 struct flowi *fl, bool strict)
96{
97 static const struct ipv6_pinfo fake_pinfo;
98 static const struct inet_sock fake_sk = {
99 /* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */
100 .sk.sk_bound_dev_if = 1,
101 .pinet6 = (struct ipv6_pinfo *) &fake_pinfo,
102 };
103 const void *sk = strict ? &fake_sk : NULL;
104 struct dst_entry *result;
105 int err;
106
107 result = ip6_route_output(net, sk, &fl->u.ip6);
108 err = result->error;
109 if (err)
110 dst_release(result);
111 else
112 *dst = result;
113 return err;
114}
115
116__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
117 unsigned int dataoff, u_int8_t protocol)
118{
119 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
120 __sum16 csum = 0;
121
122 switch (skb->ip_summed) {
123 case CHECKSUM_COMPLETE:
124 if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN)
125 break;
126 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
127 skb->len - dataoff, protocol,
128 csum_sub(skb->csum,
129 skb_checksum(skb, 0,
130 dataoff, 0)))) {
131 skb->ip_summed = CHECKSUM_UNNECESSARY;
132 break;
133 }
134 /* fall through */
135 case CHECKSUM_NONE:
136 skb->csum = ~csum_unfold(
137 csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
138 skb->len - dataoff,
139 protocol,
140 csum_sub(0,
141 skb_checksum(skb, 0,
142 dataoff, 0))));
143 csum = __skb_checksum_complete(skb);
144 }
145 return csum;
146}
147EXPORT_SYMBOL(nf_ip6_checksum);
148
149static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook,
150 unsigned int dataoff, unsigned int len,
151 u_int8_t protocol)
152{
153 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
154 __wsum hsum;
155 __sum16 csum = 0;
156
157 switch (skb->ip_summed) {
158 case CHECKSUM_COMPLETE:
159 if (len == skb->len - dataoff)
160 return nf_ip6_checksum(skb, hook, dataoff, protocol);
161 /* fall through */
162 case CHECKSUM_NONE:
163 hsum = skb_checksum(skb, 0, dataoff, 0);
164 skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
165 &ip6h->daddr,
166 skb->len - dataoff,
167 protocol,
168 csum_sub(0, hsum)));
169 skb->ip_summed = CHECKSUM_NONE;
170 return __skb_checksum_complete_head(skb, dataoff + len);
171 }
172 return csum;
173};
174
175static const struct nf_afinfo nf_ip6_afinfo = {
176 .family = AF_INET6,
177 .checksum = nf_ip6_checksum,
178 .checksum_partial = nf_ip6_checksum_partial,
179 .route = nf_ip6_route,
180 .saveroute = nf_ip6_saveroute,
181 .reroute = nf_ip6_reroute,
182 .route_key_size = sizeof(struct ip6_rt_info),
183};
184
185int __init ipv6_netfilter_init(void)
186{
187 return nf_register_afinfo(&nf_ip6_afinfo);
188}
189
190/* This can be called from inet6_init() on errors, so it cannot
191 * be marked __exit. -DaveM
192 */
193void ipv6_netfilter_fini(void)
194{
195 nf_unregister_afinfo(&nf_ip6_afinfo);
196}