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> | |
862b82c6 | 15 | #include <linux/netfilter.h> |
406ef77c HX |
16 | #include <linux/skbuff.h> |
17 | #include <linux/spinlock.h> | |
406ef77c HX |
18 | #include <net/dst.h> |
19 | #include <net/xfrm.h> | |
20 | ||
c6581a45 HX |
21 | static int xfrm_output2(struct sk_buff *skb); |
22 | ||
83815dea HX |
23 | static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb) |
24 | { | |
550ade84 HX |
25 | struct dst_entry *dst = skb->dst; |
26 | int nhead = dst->header_len + LL_RESERVED_SPACE(dst->dev) | |
83815dea HX |
27 | - skb_headroom(skb); |
28 | ||
29 | if (nhead > 0) | |
30 | return pskb_expand_head(skb, nhead, 0, GFP_ATOMIC); | |
31 | ||
32 | /* Check tail too... */ | |
33 | return 0; | |
34 | } | |
35 | ||
36 | static int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb) | |
37 | { | |
38 | int err = xfrm_state_check_expire(x); | |
39 | if (err < 0) | |
40 | goto err; | |
41 | err = xfrm_state_check_space(x, skb); | |
42 | err: | |
43 | return err; | |
44 | } | |
45 | ||
c6581a45 | 46 | static int xfrm_output_one(struct sk_buff *skb, int err) |
406ef77c HX |
47 | { |
48 | struct dst_entry *dst = skb->dst; | |
49 | struct xfrm_state *x = dst->xfrm; | |
406ef77c | 50 | |
c6581a45 HX |
51 | if (err <= 0) |
52 | goto resume; | |
406ef77c HX |
53 | |
54 | do { | |
a2deb6d2 HX |
55 | err = x->outer_mode->output(x, skb); |
56 | if (err) | |
57 | goto error; | |
58 | ||
406ef77c HX |
59 | spin_lock_bh(&x->lock); |
60 | err = xfrm_state_check(x, skb); | |
61 | if (err) | |
62 | goto error; | |
63 | ||
436a0a40 HX |
64 | if (x->type->flags & XFRM_TYPE_REPLAY_PROT) { |
65 | XFRM_SKB_CB(skb)->seq = ++x->replay.oseq; | |
cdf7e668 HX |
66 | if (xfrm_aevent_is_on()) |
67 | xfrm_replay_notify(x, XFRM_REPLAY_UPDATE); | |
436a0a40 HX |
68 | } |
69 | ||
406ef77c HX |
70 | x->curlft.bytes += skb->len; |
71 | x->curlft.packets++; | |
72 | ||
406ef77c HX |
73 | spin_unlock_bh(&x->lock); |
74 | ||
b7c6538c | 75 | err = x->type->output(x, skb); |
c6581a45 HX |
76 | |
77 | resume: | |
b7c6538c HX |
78 | if (err) |
79 | goto error_nolock; | |
80 | ||
406ef77c HX |
81 | if (!(skb->dst = dst_pop(dst))) { |
82 | err = -EHOSTUNREACH; | |
83 | goto error_nolock; | |
84 | } | |
85 | dst = skb->dst; | |
86 | x = dst->xfrm; | |
13996378 | 87 | } while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL)); |
406ef77c HX |
88 | |
89 | err = 0; | |
90 | ||
862b82c6 | 91 | out_exit: |
406ef77c HX |
92 | return err; |
93 | error: | |
94 | spin_unlock_bh(&x->lock); | |
862b82c6 HX |
95 | error_nolock: |
96 | kfree_skb(skb); | |
97 | goto out_exit; | |
98 | } | |
99 | ||
c6581a45 | 100 | int xfrm_output_resume(struct sk_buff *skb, int err) |
862b82c6 | 101 | { |
c6581a45 | 102 | while (likely((err = xfrm_output_one(skb, err)) == 0)) { |
862b82c6 HX |
103 | struct xfrm_state *x; |
104 | ||
105 | nf_reset(skb); | |
106 | ||
107 | err = skb->dst->ops->local_out(skb); | |
108 | if (unlikely(err != 1)) | |
c6581a45 | 109 | goto out; |
862b82c6 HX |
110 | |
111 | x = skb->dst->xfrm; | |
112 | if (!x) | |
113 | return dst_output(skb); | |
114 | ||
115 | err = nf_hook(x->inner_mode->afinfo->family, | |
294b4baf | 116 | NF_INET_POST_ROUTING, skb, |
862b82c6 HX |
117 | NULL, skb->dst->dev, xfrm_output2); |
118 | if (unlikely(err != 1)) | |
c6581a45 | 119 | goto out; |
862b82c6 HX |
120 | } |
121 | ||
c6581a45 HX |
122 | if (err == -EINPROGRESS) |
123 | err = 0; | |
124 | ||
125 | out: | |
862b82c6 HX |
126 | return err; |
127 | } | |
c6581a45 | 128 | EXPORT_SYMBOL_GPL(xfrm_output_resume); |
862b82c6 | 129 | |
c6581a45 | 130 | static int xfrm_output2(struct sk_buff *skb) |
862b82c6 | 131 | { |
c6581a45 HX |
132 | return xfrm_output_resume(skb, 1); |
133 | } | |
862b82c6 | 134 | |
c6581a45 HX |
135 | static int xfrm_output_gso(struct sk_buff *skb) |
136 | { | |
137 | struct sk_buff *segs; | |
862b82c6 HX |
138 | |
139 | segs = skb_gso_segment(skb, 0); | |
140 | kfree_skb(skb); | |
141 | if (unlikely(IS_ERR(segs))) | |
142 | return PTR_ERR(segs); | |
143 | ||
144 | do { | |
145 | struct sk_buff *nskb = segs->next; | |
146 | int err; | |
147 | ||
148 | segs->next = NULL; | |
149 | err = xfrm_output2(segs); | |
150 | ||
151 | if (unlikely(err)) { | |
152 | while ((segs = nskb)) { | |
153 | nskb = segs->next; | |
154 | segs->next = NULL; | |
155 | kfree_skb(segs); | |
156 | } | |
157 | return err; | |
158 | } | |
159 | ||
160 | segs = nskb; | |
161 | } while (segs); | |
162 | ||
163 | return 0; | |
406ef77c | 164 | } |
c6581a45 HX |
165 | |
166 | int xfrm_output(struct sk_buff *skb) | |
167 | { | |
168 | int err; | |
169 | ||
170 | if (skb_is_gso(skb)) | |
171 | return xfrm_output_gso(skb); | |
172 | ||
173 | if (skb->ip_summed == CHECKSUM_PARTIAL) { | |
174 | err = skb_checksum_help(skb); | |
175 | if (err) { | |
176 | kfree_skb(skb); | |
177 | return err; | |
178 | } | |
179 | } | |
180 | ||
181 | return xfrm_output2(skb); | |
182 | } | |
406ef77c | 183 | EXPORT_SYMBOL_GPL(xfrm_output); |