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> | |
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 | ||
c6581a45 | 36 | static int xfrm_output_one(struct sk_buff *skb, int err) |
406ef77c HX |
37 | { |
38 | struct dst_entry *dst = skb->dst; | |
39 | struct xfrm_state *x = dst->xfrm; | |
406ef77c | 40 | |
c6581a45 HX |
41 | if (err <= 0) |
42 | goto resume; | |
406ef77c HX |
43 | |
44 | do { | |
910ef70a | 45 | err = xfrm_state_check_space(x, skb); |
b15c4bcd MN |
46 | if (err) { |
47 | XFRM_INC_STATS(LINUX_MIB_XFRMOUTERROR); | |
910ef70a | 48 | goto error_nolock; |
b15c4bcd | 49 | } |
910ef70a | 50 | |
a2deb6d2 | 51 | err = x->outer_mode->output(x, skb); |
b15c4bcd MN |
52 | if (err) { |
53 | XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATEMODEERROR); | |
910ef70a | 54 | goto error_nolock; |
b15c4bcd | 55 | } |
a2deb6d2 | 56 | |
406ef77c | 57 | spin_lock_bh(&x->lock); |
910ef70a | 58 | err = xfrm_state_check_expire(x); |
b15c4bcd MN |
59 | if (err) { |
60 | XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATEEXPIRED); | |
406ef77c | 61 | goto error; |
b15c4bcd | 62 | } |
406ef77c | 63 | |
436a0a40 | 64 | if (x->type->flags & XFRM_TYPE_REPLAY_PROT) { |
b318e0e4 | 65 | XFRM_SKB_CB(skb)->seq.output = ++x->replay.oseq; |
e1af9f27 | 66 | if (unlikely(x->replay.oseq == 0)) { |
9472c9ef | 67 | XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATESEQERROR); |
e1af9f27 | 68 | x->replay.oseq--; |
afeb14b4 | 69 | xfrm_audit_state_replay_overflow(x, skb); |
dbb1db8b | 70 | err = -EOVERFLOW; |
e1af9f27 PM |
71 | goto error; |
72 | } | |
cdf7e668 HX |
73 | if (xfrm_aevent_is_on()) |
74 | xfrm_replay_notify(x, XFRM_REPLAY_UPDATE); | |
436a0a40 HX |
75 | } |
76 | ||
406ef77c HX |
77 | x->curlft.bytes += skb->len; |
78 | x->curlft.packets++; | |
79 | ||
406ef77c HX |
80 | spin_unlock_bh(&x->lock); |
81 | ||
b7c6538c | 82 | err = x->type->output(x, skb); |
fcb8c156 HX |
83 | if (err == -EINPROGRESS) |
84 | goto out_exit; | |
c6581a45 HX |
85 | |
86 | resume: | |
0aa64774 MN |
87 | if (err) { |
88 | XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATEPROTOERROR); | |
b7c6538c | 89 | goto error_nolock; |
0aa64774 | 90 | } |
b7c6538c | 91 | |
406ef77c | 92 | if (!(skb->dst = dst_pop(dst))) { |
0aa64774 | 93 | XFRM_INC_STATS(LINUX_MIB_XFRMOUTERROR); |
406ef77c HX |
94 | err = -EHOSTUNREACH; |
95 | goto error_nolock; | |
96 | } | |
97 | dst = skb->dst; | |
98 | x = dst->xfrm; | |
13996378 | 99 | } while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL)); |
406ef77c HX |
100 | |
101 | err = 0; | |
102 | ||
862b82c6 | 103 | out_exit: |
406ef77c HX |
104 | return err; |
105 | error: | |
106 | spin_unlock_bh(&x->lock); | |
862b82c6 HX |
107 | error_nolock: |
108 | kfree_skb(skb); | |
109 | goto out_exit; | |
110 | } | |
111 | ||
c6581a45 | 112 | int xfrm_output_resume(struct sk_buff *skb, int err) |
862b82c6 | 113 | { |
c6581a45 | 114 | while (likely((err = xfrm_output_one(skb, err)) == 0)) { |
862b82c6 HX |
115 | struct xfrm_state *x; |
116 | ||
117 | nf_reset(skb); | |
118 | ||
119 | err = skb->dst->ops->local_out(skb); | |
120 | if (unlikely(err != 1)) | |
c6581a45 | 121 | goto out; |
862b82c6 HX |
122 | |
123 | x = skb->dst->xfrm; | |
124 | if (!x) | |
125 | return dst_output(skb); | |
126 | ||
df9dcb45 | 127 | err = nf_hook(skb->dst->ops->family, |
294b4baf | 128 | NF_INET_POST_ROUTING, skb, |
862b82c6 HX |
129 | NULL, skb->dst->dev, xfrm_output2); |
130 | if (unlikely(err != 1)) | |
c6581a45 | 131 | goto out; |
862b82c6 HX |
132 | } |
133 | ||
c6581a45 HX |
134 | if (err == -EINPROGRESS) |
135 | err = 0; | |
136 | ||
137 | out: | |
862b82c6 HX |
138 | return err; |
139 | } | |
c6581a45 | 140 | EXPORT_SYMBOL_GPL(xfrm_output_resume); |
862b82c6 | 141 | |
c6581a45 | 142 | static int xfrm_output2(struct sk_buff *skb) |
862b82c6 | 143 | { |
c6581a45 HX |
144 | return xfrm_output_resume(skb, 1); |
145 | } | |
862b82c6 | 146 | |
c6581a45 HX |
147 | static int xfrm_output_gso(struct sk_buff *skb) |
148 | { | |
149 | struct sk_buff *segs; | |
862b82c6 HX |
150 | |
151 | segs = skb_gso_segment(skb, 0); | |
152 | kfree_skb(skb); | |
801678c5 | 153 | if (IS_ERR(segs)) |
862b82c6 HX |
154 | return PTR_ERR(segs); |
155 | ||
156 | do { | |
157 | struct sk_buff *nskb = segs->next; | |
158 | int err; | |
159 | ||
160 | segs->next = NULL; | |
161 | err = xfrm_output2(segs); | |
162 | ||
163 | if (unlikely(err)) { | |
164 | while ((segs = nskb)) { | |
165 | nskb = segs->next; | |
166 | segs->next = NULL; | |
167 | kfree_skb(segs); | |
168 | } | |
169 | return err; | |
170 | } | |
171 | ||
172 | segs = nskb; | |
173 | } while (segs); | |
174 | ||
175 | return 0; | |
406ef77c | 176 | } |
c6581a45 HX |
177 | |
178 | int xfrm_output(struct sk_buff *skb) | |
179 | { | |
180 | int err; | |
181 | ||
182 | if (skb_is_gso(skb)) | |
183 | return xfrm_output_gso(skb); | |
184 | ||
185 | if (skb->ip_summed == CHECKSUM_PARTIAL) { | |
186 | err = skb_checksum_help(skb); | |
187 | if (err) { | |
0aa64774 | 188 | XFRM_INC_STATS(LINUX_MIB_XFRMOUTERROR); |
c6581a45 HX |
189 | kfree_skb(skb); |
190 | return err; | |
191 | } | |
192 | } | |
193 | ||
194 | return xfrm_output2(skb); | |
195 | } | |
df9dcb45 KM |
196 | |
197 | int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb) | |
198 | { | |
199 | struct xfrm_mode *inner_mode; | |
200 | if (x->sel.family == AF_UNSPEC) | |
201 | inner_mode = xfrm_ip2inner_mode(x, | |
202 | xfrm_af2proto(skb->dst->ops->family)); | |
203 | else | |
204 | inner_mode = x->inner_mode; | |
205 | ||
206 | if (inner_mode == NULL) | |
207 | return -EAFNOSUPPORT; | |
208 | return inner_mode->afinfo->extract_output(x, skb); | |
209 | } | |
210 | ||
406ef77c | 211 | EXPORT_SYMBOL_GPL(xfrm_output); |
df9dcb45 | 212 | EXPORT_SYMBOL_GPL(xfrm_inner_extract_output); |