Commit | Line | Data |
---|---|---|
0a69452c DB |
1 | /* |
2 | * xfrm6_mode_beet.c - BEET mode encapsulation for IPv6. | |
3 | * | |
4 | * Copyright (c) 2006 Diego Beltrami <diego.beltrami@gmail.com> | |
5 | * Miika Komu <miika@iki.fi> | |
6 | * Herbert Xu <herbert@gondor.apana.org.au> | |
7 | * Abhinav Pathak <abhinav.pathak@hiit.fi> | |
8 | * Jeff Ahrenholz <ahrenholz@gmail.com> | |
9 | */ | |
10 | ||
11 | #include <linux/init.h> | |
12 | #include <linux/kernel.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/skbuff.h> | |
15 | #include <linux/stringify.h> | |
16 | #include <net/dsfield.h> | |
17 | #include <net/dst.h> | |
18 | #include <net/inet_ecn.h> | |
19 | #include <net/ipv6.h> | |
20 | #include <net/xfrm.h> | |
21 | ||
227620e2 HX |
22 | static void xfrm6_beet_make_header(struct sk_buff *skb) |
23 | { | |
24 | struct ipv6hdr *iph = ipv6_hdr(skb); | |
25 | ||
26 | iph->version = 6; | |
27 | ||
28 | memcpy(iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl, | |
29 | sizeof(iph->flow_lbl)); | |
30 | iph->nexthdr = XFRM_MODE_SKB_CB(skb)->protocol; | |
31 | ||
32 | ipv6_change_dsfield(iph, 0, XFRM_MODE_SKB_CB(skb)->tos); | |
33 | iph->hop_limit = XFRM_MODE_SKB_CB(skb)->ttl; | |
34 | } | |
35 | ||
0a69452c DB |
36 | /* Add encapsulation header. |
37 | * | |
38 | * The top IP header will be constructed per draft-nikander-esp-beet-mode-06.txt. | |
0a69452c DB |
39 | */ |
40 | static int xfrm6_beet_output(struct xfrm_state *x, struct sk_buff *skb) | |
41 | { | |
36cf9acf | 42 | struct ipv6hdr *top_iph; |
abf5cdb8 JK |
43 | struct ip_beet_phdr *ph; |
44 | struct iphdr *iphv4; | |
45 | int optlen, hdr_len; | |
0a69452c | 46 | |
abf5cdb8 JK |
47 | iphv4 = ip_hdr(skb); |
48 | hdr_len = 0; | |
49 | optlen = XFRM_MODE_SKB_CB(skb)->optlen; | |
50 | if (unlikely(optlen)) | |
51 | hdr_len += IPV4_BEET_PHMAXLEN - (optlen & 4); | |
52 | ||
53 | skb_set_network_header(skb, -x->props.header_len - hdr_len); | |
54 | if (x->sel.family != AF_INET6) | |
55 | skb->network_header += IPV4_BEET_PHMAXLEN; | |
36cf9acf HX |
56 | skb->mac_header = skb->network_header + |
57 | offsetof(struct ipv6hdr, nexthdr); | |
58 | skb->transport_header = skb->network_header + sizeof(*top_iph); | |
abf5cdb8 | 59 | ph = (struct ip_beet_phdr *)__skb_pull(skb, XFRM_MODE_SKB_CB(skb)->ihl-hdr_len); |
0a69452c | 60 | |
227620e2 | 61 | xfrm6_beet_make_header(skb); |
36cf9acf | 62 | |
227620e2 | 63 | top_iph = ipv6_hdr(skb); |
abf5cdb8 JK |
64 | if (unlikely(optlen)) { |
65 | ||
66 | BUG_ON(optlen < 0); | |
67 | ||
68 | ph->padlen = 4 - (optlen & 4); | |
69 | ph->hdrlen = optlen / 8; | |
70 | ph->nexthdr = top_iph->nexthdr; | |
71 | if (ph->padlen) | |
72 | memset(ph + 1, IPOPT_NOP, ph->padlen); | |
73 | ||
74 | top_iph->nexthdr = IPPROTO_BEETPH; | |
75 | } | |
36cf9acf | 76 | |
0a69452c DB |
77 | ipv6_addr_copy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr); |
78 | ipv6_addr_copy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr); | |
0a69452c DB |
79 | return 0; |
80 | } | |
81 | ||
82 | static int xfrm6_beet_input(struct xfrm_state *x, struct sk_buff *skb) | |
83 | { | |
84 | struct ipv6hdr *ip6h; | |
39f69c6f | 85 | const unsigned char *old_mac; |
0a69452c | 86 | int size = sizeof(struct ipv6hdr); |
227620e2 | 87 | int err; |
0a69452c | 88 | |
227620e2 HX |
89 | err = skb_cow_head(skb, size + skb->mac_len); |
90 | if (err) | |
0a69452c DB |
91 | goto out; |
92 | ||
227620e2 | 93 | __skb_push(skb, size); |
c1d2bbe1 | 94 | skb_reset_network_header(skb); |
0a69452c | 95 | |
98e399f8 | 96 | old_mac = skb_mac_header(skb); |
39f69c6f | 97 | skb_set_mac_header(skb, -skb->mac_len); |
98e399f8 | 98 | memmove(skb_mac_header(skb), old_mac, skb->mac_len); |
0a69452c | 99 | |
227620e2 HX |
100 | xfrm6_beet_make_header(skb); |
101 | ||
0660e03f | 102 | ip6h = ipv6_hdr(skb); |
0a69452c DB |
103 | ip6h->payload_len = htons(skb->len - size); |
104 | ipv6_addr_copy(&ip6h->daddr, (struct in6_addr *) &x->sel.daddr.a6); | |
105 | ipv6_addr_copy(&ip6h->saddr, (struct in6_addr *) &x->sel.saddr.a6); | |
106 | err = 0; | |
107 | out: | |
108 | return err; | |
109 | } | |
110 | ||
111 | static struct xfrm_mode xfrm6_beet_mode = { | |
227620e2 HX |
112 | .input2 = xfrm6_beet_input, |
113 | .input = xfrm_prepare_input, | |
36cf9acf HX |
114 | .output2 = xfrm6_beet_output, |
115 | .output = xfrm6_prepare_output, | |
0a69452c DB |
116 | .owner = THIS_MODULE, |
117 | .encap = XFRM_MODE_BEET, | |
1bfcb10f | 118 | .flags = XFRM_MODE_FLAG_TUNNEL, |
0a69452c DB |
119 | }; |
120 | ||
121 | static int __init xfrm6_beet_init(void) | |
122 | { | |
123 | return xfrm_register_mode(&xfrm6_beet_mode, AF_INET6); | |
124 | } | |
125 | ||
126 | static void __exit xfrm6_beet_exit(void) | |
127 | { | |
128 | int err; | |
129 | ||
130 | err = xfrm_unregister_mode(&xfrm6_beet_mode, AF_INET6); | |
131 | BUG_ON(err); | |
132 | } | |
133 | ||
134 | module_init(xfrm6_beet_init); | |
135 | module_exit(xfrm6_beet_exit); | |
136 | MODULE_LICENSE("GPL"); | |
137 | MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_BEET); |