2 * xfrm_output.c - Common IPsec encapsulation code.
4 * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
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.
12 #include <linux/errno.h>
13 #include <linux/module.h>
14 #include <linux/netdevice.h>
15 #include <linux/netfilter.h>
16 #include <linux/skbuff.h>
17 #include <linux/spinlock.h>
21 static int xfrm_output2(struct sk_buff
*skb
);
23 static int xfrm_state_check_space(struct xfrm_state
*x
, struct sk_buff
*skb
)
25 struct dst_entry
*dst
= skb
->dst
;
26 int nhead
= dst
->header_len
+ LL_RESERVED_SPACE(dst
->dev
)
28 int ntail
= dst
->dev
->needed_tailroom
- skb_tailroom(skb
);
30 if (nhead
> 0 || ntail
> 0)
31 return pskb_expand_head(skb
, nhead
, ntail
, GFP_ATOMIC
);
36 static int xfrm_output_one(struct sk_buff
*skb
, int err
)
38 struct dst_entry
*dst
= skb
->dst
;
39 struct xfrm_state
*x
= dst
->xfrm
;
45 err
= xfrm_state_check_space(x
, skb
);
47 XFRM_INC_STATS(LINUX_MIB_XFRMOUTERROR
);
51 err
= x
->outer_mode
->output(x
, skb
);
53 XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATEMODEERROR
);
57 spin_lock_bh(&x
->lock
);
58 err
= xfrm_state_check_expire(x
);
60 XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATEEXPIRED
);
64 if (x
->type
->flags
& XFRM_TYPE_REPLAY_PROT
) {
65 XFRM_SKB_CB(skb
)->seq
.output
= ++x
->replay
.oseq
;
66 if (unlikely(x
->replay
.oseq
== 0)) {
67 XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATESEQERROR
);
69 xfrm_audit_state_replay_overflow(x
, skb
);
73 if (xfrm_aevent_is_on())
74 xfrm_replay_notify(x
, XFRM_REPLAY_UPDATE
);
77 x
->curlft
.bytes
+= skb
->len
;
80 spin_unlock_bh(&x
->lock
);
82 err
= x
->type
->output(x
, skb
);
83 if (err
== -EINPROGRESS
)
88 XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATEPROTOERROR
);
92 if (!(skb
->dst
= dst_pop(dst
))) {
93 XFRM_INC_STATS(LINUX_MIB_XFRMOUTERROR
);
99 } while (x
&& !(x
->outer_mode
->flags
& XFRM_MODE_FLAG_TUNNEL
));
106 spin_unlock_bh(&x
->lock
);
112 int xfrm_output_resume(struct sk_buff
*skb
, int err
)
114 while (likely((err
= xfrm_output_one(skb
, err
)) == 0)) {
117 err
= skb
->dst
->ops
->local_out(skb
);
118 if (unlikely(err
!= 1))
122 return dst_output(skb
);
124 err
= nf_hook(skb
->dst
->ops
->family
,
125 NF_INET_POST_ROUTING
, skb
,
126 NULL
, skb
->dst
->dev
, xfrm_output2
);
127 if (unlikely(err
!= 1))
131 if (err
== -EINPROGRESS
)
137 EXPORT_SYMBOL_GPL(xfrm_output_resume
);
139 static int xfrm_output2(struct sk_buff
*skb
)
141 return xfrm_output_resume(skb
, 1);
144 static int xfrm_output_gso(struct sk_buff
*skb
)
146 struct sk_buff
*segs
;
148 segs
= skb_gso_segment(skb
, 0);
151 return PTR_ERR(segs
);
154 struct sk_buff
*nskb
= segs
->next
;
158 err
= xfrm_output2(segs
);
161 while ((segs
= nskb
)) {
175 int xfrm_output(struct sk_buff
*skb
)
180 return xfrm_output_gso(skb
);
182 if (skb
->ip_summed
== CHECKSUM_PARTIAL
) {
183 err
= skb_checksum_help(skb
);
185 XFRM_INC_STATS(LINUX_MIB_XFRMOUTERROR
);
191 return xfrm_output2(skb
);
194 int xfrm_inner_extract_output(struct xfrm_state
*x
, struct sk_buff
*skb
)
196 struct xfrm_mode
*inner_mode
;
197 if (x
->sel
.family
== AF_UNSPEC
)
198 inner_mode
= xfrm_ip2inner_mode(x
,
199 xfrm_af2proto(skb
->dst
->ops
->family
));
201 inner_mode
= x
->inner_mode
;
203 if (inner_mode
== NULL
)
204 return -EAFNOSUPPORT
;
205 return inner_mode
->afinfo
->extract_output(x
, skb
);
208 EXPORT_SYMBOL_GPL(xfrm_output
);
209 EXPORT_SYMBOL_GPL(xfrm_inner_extract_output
);