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> | |
17 | #include <linux/time.h> | |
18 | #include <net/dst.h> | |
19 | #include <net/xfrm.h> | |
20 | ||
83815dea HX |
21 | static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb) |
22 | { | |
23 | int nhead = x->props.header_len + LL_RESERVED_SPACE(skb->dst->dev) | |
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 { | |
56 | spin_lock_bh(&x->lock); | |
57 | err = xfrm_state_check(x, skb); | |
58 | if (err) | |
59 | goto error; | |
60 | ||
61 | err = x->mode->output(x, skb); | |
62 | if (err) | |
63 | goto error; | |
64 | ||
65 | err = x->type->output(x, skb); | |
66 | if (err) | |
67 | goto error; | |
68 | ||
69 | x->curlft.bytes += skb->len; | |
70 | x->curlft.packets++; | |
71 | ||
72 | if (x->props.mode == XFRM_MODE_ROUTEOPTIMIZATION) | |
73 | x->lastused = get_seconds(); | |
74 | ||
75 | spin_unlock_bh(&x->lock); | |
76 | ||
77 | skb_reset_network_header(skb); | |
78 | ||
79 | if (!(skb->dst = dst_pop(dst))) { | |
80 | err = -EHOSTUNREACH; | |
81 | goto error_nolock; | |
82 | } | |
83 | dst = skb->dst; | |
84 | x = dst->xfrm; | |
85 | } while (x && (x->props.mode != XFRM_MODE_TUNNEL)); | |
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); |