Commit | Line | Data |
---|---|---|
406ef77c HX |
1 | /* |
2 | * xfrm_output.c - Common IPsec encapsulation code. | |
3 | * | |
4 | * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #include <linux/errno.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/netdevice.h> | |
15 | #include <linux/skbuff.h> | |
16 | #include <linux/spinlock.h> | |
406ef77c HX |
17 | #include <net/dst.h> |
18 | #include <net/xfrm.h> | |
19 | ||
83815dea HX |
20 | static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb) |
21 | { | |
550ade84 HX |
22 | struct dst_entry *dst = skb->dst; |
23 | int nhead = dst->header_len + LL_RESERVED_SPACE(dst->dev) | |
83815dea HX |
24 | - skb_headroom(skb); |
25 | ||
26 | if (nhead > 0) | |
27 | return pskb_expand_head(skb, nhead, 0, GFP_ATOMIC); | |
28 | ||
29 | /* Check tail too... */ | |
30 | return 0; | |
31 | } | |
32 | ||
33 | static int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb) | |
34 | { | |
35 | int err = xfrm_state_check_expire(x); | |
36 | if (err < 0) | |
37 | goto err; | |
38 | err = xfrm_state_check_space(x, skb); | |
39 | err: | |
40 | return err; | |
41 | } | |
42 | ||
406ef77c HX |
43 | int xfrm_output(struct sk_buff *skb) |
44 | { | |
45 | struct dst_entry *dst = skb->dst; | |
46 | struct xfrm_state *x = dst->xfrm; | |
47 | int err; | |
48 | ||
49 | if (skb->ip_summed == CHECKSUM_PARTIAL) { | |
50 | err = skb_checksum_help(skb); | |
51 | if (err) | |
52 | goto error_nolock; | |
53 | } | |
54 | ||
55 | do { | |
a2deb6d2 HX |
56 | err = x->outer_mode->output(x, skb); |
57 | if (err) | |
58 | goto error; | |
59 | ||
406ef77c HX |
60 | spin_lock_bh(&x->lock); |
61 | err = xfrm_state_check(x, skb); | |
62 | if (err) | |
63 | goto error; | |
64 | ||
436a0a40 HX |
65 | if (x->type->flags & XFRM_TYPE_REPLAY_PROT) { |
66 | XFRM_SKB_CB(skb)->seq = ++x->replay.oseq; | |
cdf7e668 HX |
67 | if (xfrm_aevent_is_on()) |
68 | xfrm_replay_notify(x, XFRM_REPLAY_UPDATE); | |
436a0a40 HX |
69 | } |
70 | ||
406ef77c HX |
71 | x->curlft.bytes += skb->len; |
72 | x->curlft.packets++; | |
73 | ||
406ef77c HX |
74 | spin_unlock_bh(&x->lock); |
75 | ||
b7c6538c HX |
76 | err = x->type->output(x, skb); |
77 | if (err) | |
78 | goto error_nolock; | |
79 | ||
406ef77c HX |
80 | if (!(skb->dst = dst_pop(dst))) { |
81 | err = -EHOSTUNREACH; | |
82 | goto error_nolock; | |
83 | } | |
84 | dst = skb->dst; | |
85 | x = dst->xfrm; | |
13996378 | 86 | } while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL)); |
406ef77c HX |
87 | |
88 | err = 0; | |
89 | ||
90 | error_nolock: | |
91 | return err; | |
92 | error: | |
93 | spin_unlock_bh(&x->lock); | |
94 | goto error_nolock; | |
95 | } | |
96 | EXPORT_SYMBOL_GPL(xfrm_output); |