diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/ipv4/xfrm4_output.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/ipv4/xfrm4_output.c')
-rw-r--r-- | net/ipv4/xfrm4_output.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c new file mode 100644 index 000000000000..af2392ae5769 --- /dev/null +++ b/net/ipv4/xfrm4_output.c | |||
@@ -0,0 +1,141 @@ | |||
1 | /* | ||
2 | * xfrm4_output.c - Common IPsec encapsulation code for IPv4. | ||
3 | * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au> | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or | ||
6 | * modify it under the terms of the GNU General Public License | ||
7 | * as published by the Free Software Foundation; either version | ||
8 | * 2 of the License, or (at your option) any later version. | ||
9 | */ | ||
10 | |||
11 | #include <linux/skbuff.h> | ||
12 | #include <linux/spinlock.h> | ||
13 | #include <net/inet_ecn.h> | ||
14 | #include <net/ip.h> | ||
15 | #include <net/xfrm.h> | ||
16 | #include <net/icmp.h> | ||
17 | |||
18 | /* Add encapsulation header. | ||
19 | * | ||
20 | * In transport mode, the IP header will be moved forward to make space | ||
21 | * for the encapsulation header. | ||
22 | * | ||
23 | * In tunnel mode, the top IP header will be constructed per RFC 2401. | ||
24 | * The following fields in it shall be filled in by x->type->output: | ||
25 | * tot_len | ||
26 | * check | ||
27 | * | ||
28 | * On exit, skb->h will be set to the start of the payload to be processed | ||
29 | * by x->type->output and skb->nh will be set to the top IP header. | ||
30 | */ | ||
31 | static void xfrm4_encap(struct sk_buff *skb) | ||
32 | { | ||
33 | struct dst_entry *dst = skb->dst; | ||
34 | struct xfrm_state *x = dst->xfrm; | ||
35 | struct iphdr *iph, *top_iph; | ||
36 | |||
37 | iph = skb->nh.iph; | ||
38 | skb->h.ipiph = iph; | ||
39 | |||
40 | skb->nh.raw = skb_push(skb, x->props.header_len); | ||
41 | top_iph = skb->nh.iph; | ||
42 | |||
43 | if (!x->props.mode) { | ||
44 | skb->h.raw += iph->ihl*4; | ||
45 | memmove(top_iph, iph, iph->ihl*4); | ||
46 | return; | ||
47 | } | ||
48 | |||
49 | top_iph->ihl = 5; | ||
50 | top_iph->version = 4; | ||
51 | |||
52 | /* DS disclosed */ | ||
53 | top_iph->tos = INET_ECN_encapsulate(iph->tos, iph->tos); | ||
54 | if (x->props.flags & XFRM_STATE_NOECN) | ||
55 | IP_ECN_clear(top_iph); | ||
56 | |||
57 | top_iph->frag_off = iph->frag_off & htons(IP_DF); | ||
58 | if (!top_iph->frag_off) | ||
59 | __ip_select_ident(top_iph, dst, 0); | ||
60 | |||
61 | top_iph->ttl = dst_metric(dst->child, RTAX_HOPLIMIT); | ||
62 | |||
63 | top_iph->saddr = x->props.saddr.a4; | ||
64 | top_iph->daddr = x->id.daddr.a4; | ||
65 | top_iph->protocol = IPPROTO_IPIP; | ||
66 | |||
67 | memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options)); | ||
68 | } | ||
69 | |||
70 | static int xfrm4_tunnel_check_size(struct sk_buff *skb) | ||
71 | { | ||
72 | int mtu, ret = 0; | ||
73 | struct dst_entry *dst; | ||
74 | struct iphdr *iph = skb->nh.iph; | ||
75 | |||
76 | if (IPCB(skb)->flags & IPSKB_XFRM_TUNNEL_SIZE) | ||
77 | goto out; | ||
78 | |||
79 | IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE; | ||
80 | |||
81 | if (!(iph->frag_off & htons(IP_DF)) || skb->local_df) | ||
82 | goto out; | ||
83 | |||
84 | dst = skb->dst; | ||
85 | mtu = dst_mtu(dst); | ||
86 | if (skb->len > mtu) { | ||
87 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); | ||
88 | ret = -EMSGSIZE; | ||
89 | } | ||
90 | out: | ||
91 | return ret; | ||
92 | } | ||
93 | |||
94 | int xfrm4_output(struct sk_buff *skb) | ||
95 | { | ||
96 | struct dst_entry *dst = skb->dst; | ||
97 | struct xfrm_state *x = dst->xfrm; | ||
98 | int err; | ||
99 | |||
100 | if (skb->ip_summed == CHECKSUM_HW) { | ||
101 | err = skb_checksum_help(skb, 0); | ||
102 | if (err) | ||
103 | goto error_nolock; | ||
104 | } | ||
105 | |||
106 | if (x->props.mode) { | ||
107 | err = xfrm4_tunnel_check_size(skb); | ||
108 | if (err) | ||
109 | goto error_nolock; | ||
110 | } | ||
111 | |||
112 | spin_lock_bh(&x->lock); | ||
113 | err = xfrm_state_check(x, skb); | ||
114 | if (err) | ||
115 | goto error; | ||
116 | |||
117 | xfrm4_encap(skb); | ||
118 | |||
119 | err = x->type->output(x, skb); | ||
120 | if (err) | ||
121 | goto error; | ||
122 | |||
123 | x->curlft.bytes += skb->len; | ||
124 | x->curlft.packets++; | ||
125 | |||
126 | spin_unlock_bh(&x->lock); | ||
127 | |||
128 | if (!(skb->dst = dst_pop(dst))) { | ||
129 | err = -EHOSTUNREACH; | ||
130 | goto error_nolock; | ||
131 | } | ||
132 | err = NET_XMIT_BYPASS; | ||
133 | |||
134 | out_exit: | ||
135 | return err; | ||
136 | error: | ||
137 | spin_unlock_bh(&x->lock); | ||
138 | error_nolock: | ||
139 | kfree_skb(skb); | ||
140 | goto out_exit; | ||
141 | } | ||