1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/*
* xfrm6_mode_tunnel.c - Tunnel mode encapsulation for IPv6.
*
* Copyright (C) 2002 USAGI/WIDE Project
* Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
*/
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/stringify.h>
#include <net/dsfield.h>
#include <net/dst.h>
#include <net/inet_ecn.h>
#include <net/ip6_route.h>
#include <net/ipv6.h>
#include <net/xfrm.h>
static inline void ipip6_ecn_decapsulate(struct sk_buff *skb)
{
struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
IP6_ECN_set_ce(skb, inner_iph);
}
/* Add encapsulation header.
*
* The top IP header will be constructed per RFC 2401.
*/
static int xfrm6_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct ipv6hdr *top_iph;
int dsfield;
skb_set_inner_network_header(skb, skb_network_offset(skb));
skb_set_inner_transport_header(skb, skb_transport_offset(skb));
skb_set_network_header(skb, -x->props.header_len);
skb->mac_header = skb->network_header +
offsetof(struct ipv6hdr, nexthdr);
skb->transport_header = skb->network_header + sizeof(*top_iph);
top_iph = ipv6_hdr(skb);
top_iph->version = 6;
memcpy(top_iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl,
sizeof(top_iph->flow_lbl));
top_iph->nexthdr = xfrm_af2proto(skb_dst(skb)->ops->family);
if (x->props.extra_flags & XFRM_SA_XFLAG_DONT_ENCAP_DSCP)
dsfield = 0;
else
dsfield = XFRM_MODE_SKB_CB(skb)->tos;
dsfield = INET_ECN_encapsulate(dsfield, XFRM_MODE_SKB_CB(skb)->tos);
if (x->props.flags & XFRM_STATE_NOECN)
dsfield &= ~INET_ECN_MASK;
ipv6_change_dsfield(top_iph, 0, dsfield);
top_iph->hop_limit = ip6_dst_hoplimit(dst->child);
top_iph->saddr = *(struct in6_addr *)&x->props.saddr;
top_iph->daddr = *(struct in6_addr *)&x->id.daddr;
return 0;
}
#define for_each_input_rcu(head, handler) \
for (handler = rcu_dereference(head); \
handler != NULL; \
handler = rcu_dereference(handler->next))
static int xfrm6_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
{
int err = -EINVAL;
if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
goto out;
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
goto out;
err = skb_unclone(skb, GFP_ATOMIC);
if (err)
goto out;
if (x->props.flags & XFRM_STATE_DECAP_DSCP)
ipv6_copy_dscp(ipv6_get_dsfield(ipv6_hdr(skb)),
ipipv6_hdr(skb));
if (!(x->props.flags & XFRM_STATE_NOECN))
ipip6_ecn_decapsulate(skb);
skb_reset_network_header(skb);
skb_mac_header_rebuild(skb);
err = 0;
out:
return err;
}
static struct sk_buff *xfrm6_mode_tunnel_gso_segment(struct xfrm_state *x,
struct sk_buff *skb,
netdev_features_t features)
{
__skb_push(skb, skb->mac_len);
return skb_mac_gso_segment(skb, features);
}
static void xfrm6_mode_tunnel_xmit(struct xfrm_state *x, struct sk_buff *skb)
{
struct xfrm_offload *xo = xfrm_offload(skb);
if (xo->flags & XFRM_GSO_SEGMENT) {
skb->network_header = skb->network_header - x->props.header_len;
skb->transport_header = skb->network_header + sizeof(struct ipv6hdr);
}
skb_reset_mac_len(skb);
pskb_pull(skb, skb->mac_len + x->props.header_len);
}
static struct xfrm_mode xfrm6_tunnel_mode = {
.input2 = xfrm6_mode_tunnel_input,
.input = xfrm_prepare_input,
.output2 = xfrm6_mode_tunnel_output,
.output = xfrm6_prepare_output,
.gso_segment = xfrm6_mode_tunnel_gso_segment,
.xmit = xfrm6_mode_tunnel_xmit,
.owner = THIS_MODULE,
.encap = XFRM_MODE_TUNNEL,
.flags = XFRM_MODE_FLAG_TUNNEL,
};
static int __init xfrm6_mode_tunnel_init(void)
{
return xfrm_register_mode(&xfrm6_tunnel_mode, AF_INET6);
}
static void __exit xfrm6_mode_tunnel_exit(void)
{
int err;
err = xfrm_unregister_mode(&xfrm6_tunnel_mode, AF_INET6);
BUG_ON(err);
}
module_init(xfrm6_mode_tunnel_init);
module_exit(xfrm6_mode_tunnel_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TUNNEL);
|
