Commit | Line | Data |
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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 | { | |
22 | int nhead = x->props.header_len + LL_RESERVED_SPACE(skb->dst->dev) | |
23 | - skb_headroom(skb); | |
24 | ||
25 | if (nhead > 0) | |
26 | return pskb_expand_head(skb, nhead, 0, GFP_ATOMIC); | |
27 | ||
28 | /* Check tail too... */ | |
29 | return 0; | |
30 | } | |
31 | ||
32 | static int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb) | |
33 | { | |
34 | int err = xfrm_state_check_expire(x); | |
35 | if (err < 0) | |
36 | goto err; | |
37 | err = xfrm_state_check_space(x, skb); | |
38 | err: | |
39 | return err; | |
40 | } | |
41 | ||
406ef77c HX |
42 | int xfrm_output(struct sk_buff *skb) |
43 | { | |
44 | struct dst_entry *dst = skb->dst; | |
45 | struct xfrm_state *x = dst->xfrm; | |
46 | int err; | |
47 | ||
48 | if (skb->ip_summed == CHECKSUM_PARTIAL) { | |
49 | err = skb_checksum_help(skb); | |
50 | if (err) | |
51 | goto error_nolock; | |
52 | } | |
53 | ||
54 | do { | |
55 | spin_lock_bh(&x->lock); | |
56 | err = xfrm_state_check(x, skb); | |
57 | if (err) | |
58 | goto error; | |
59 | ||
436a0a40 HX |
60 | if (x->type->flags & XFRM_TYPE_REPLAY_PROT) { |
61 | XFRM_SKB_CB(skb)->seq = ++x->replay.oseq; | |
cdf7e668 HX |
62 | if (xfrm_aevent_is_on()) |
63 | xfrm_replay_notify(x, XFRM_REPLAY_UPDATE); | |
436a0a40 HX |
64 | } |
65 | ||
406ef77c HX |
66 | err = x->mode->output(x, skb); |
67 | if (err) | |
68 | goto error; | |
69 | ||
406ef77c HX |
70 | x->curlft.bytes += skb->len; |
71 | x->curlft.packets++; | |
72 | ||
406ef77c HX |
73 | spin_unlock_bh(&x->lock); |
74 | ||
b7c6538c HX |
75 | err = x->type->output(x, skb); |
76 | if (err) | |
77 | goto error_nolock; | |
78 | ||
406ef77c HX |
79 | if (!(skb->dst = dst_pop(dst))) { |
80 | err = -EHOSTUNREACH; | |
81 | goto error_nolock; | |
82 | } | |
83 | dst = skb->dst; | |
84 | x = dst->xfrm; | |
1bfcb10f | 85 | } while (x && !(x->mode->flags & XFRM_MODE_FLAG_TUNNEL)); |
406ef77c HX |
86 | |
87 | err = 0; | |
88 | ||
89 | error_nolock: | |
90 | return err; | |
91 | error: | |
92 | spin_unlock_bh(&x->lock); | |
93 | goto error_nolock; | |
94 | } | |
95 | EXPORT_SYMBOL_GPL(xfrm_output); |