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/slab.h>
18 #include <linux/spinlock.h>
22 static int xfrm_output2(struct sk_buff
*skb
);
24 static int xfrm_skb_check_space(struct sk_buff
*skb
)
26 struct dst_entry
*dst
= skb_dst(skb
);
27 int nhead
= dst
->header_len
+ LL_RESERVED_SPACE(dst
->dev
)
29 int ntail
= dst
->dev
->needed_tailroom
- skb_tailroom(skb
);
38 return pskb_expand_head(skb
, nhead
, ntail
, GFP_ATOMIC
);
41 static int xfrm_output_one(struct sk_buff
*skb
, int err
)
43 struct dst_entry
*dst
= skb_dst(skb
);
44 struct xfrm_state
*x
= dst
->xfrm
;
45 struct net
*net
= xs_net(x
);
51 err
= xfrm_skb_check_space(skb
);
53 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTERROR
);
57 err
= x
->outer_mode
->output(x
, skb
);
59 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTSTATEMODEERROR
);
63 spin_lock_bh(&x
->lock
);
65 if (unlikely(x
->km
.state
!= XFRM_STATE_VALID
)) {
66 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTSTATEINVALID
);
71 err
= xfrm_state_check_expire(x
);
73 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTSTATEEXPIRED
);
77 err
= x
->repl
->overflow(x
, skb
);
79 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTSTATESEQERROR
);
83 x
->curlft
.bytes
+= skb
->len
;
86 spin_unlock_bh(&x
->lock
);
90 err
= x
->type
->output(x
, skb
);
91 if (err
== -EINPROGRESS
)
96 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTSTATEPROTOERROR
);
100 dst
= skb_dst_pop(skb
);
102 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTERROR
);
106 skb_dst_set(skb
, dst
);
108 } while (x
&& !(x
->outer_mode
->flags
& XFRM_MODE_FLAG_TUNNEL
));
115 spin_unlock_bh(&x
->lock
);
121 int xfrm_output_resume(struct sk_buff
*skb
, int err
)
123 while (likely((err
= xfrm_output_one(skb
, err
)) == 0)) {
126 err
= skb_dst(skb
)->ops
->local_out(skb
);
127 if (unlikely(err
!= 1))
130 if (!skb_dst(skb
)->xfrm
)
131 return dst_output(skb
);
133 err
= nf_hook(skb_dst(skb
)->ops
->family
,
134 NF_INET_POST_ROUTING
, skb
,
135 NULL
, skb_dst(skb
)->dev
, xfrm_output2
);
136 if (unlikely(err
!= 1))
140 if (err
== -EINPROGRESS
)
146 EXPORT_SYMBOL_GPL(xfrm_output_resume
);
148 static int xfrm_output2(struct sk_buff
*skb
)
150 return xfrm_output_resume(skb
, 1);
153 static int xfrm_output_gso(struct sk_buff
*skb
)
155 struct sk_buff
*segs
;
157 segs
= skb_gso_segment(skb
, 0);
160 return PTR_ERR(segs
);
163 struct sk_buff
*nskb
= segs
->next
;
167 err
= xfrm_output2(segs
);
170 while ((segs
= nskb
)) {
184 int xfrm_output(struct sk_buff
*skb
)
186 struct net
*net
= dev_net(skb_dst(skb
)->dev
);
190 return xfrm_output_gso(skb
);
192 if (skb
->ip_summed
== CHECKSUM_PARTIAL
) {
193 err
= skb_checksum_help(skb
);
195 XFRM_INC_STATS(net
, LINUX_MIB_XFRMOUTERROR
);
201 return xfrm_output2(skb
);
204 int xfrm_inner_extract_output(struct xfrm_state
*x
, struct sk_buff
*skb
)
206 struct xfrm_mode
*inner_mode
;
207 if (x
->sel
.family
== AF_UNSPEC
)
208 inner_mode
= xfrm_ip2inner_mode(x
,
209 xfrm_af2proto(skb_dst(skb
)->ops
->family
));
211 inner_mode
= x
->inner_mode
;
213 if (inner_mode
== NULL
)
214 return -EAFNOSUPPORT
;
215 return inner_mode
->afinfo
->extract_output(x
, skb
);
218 EXPORT_SYMBOL_GPL(xfrm_output
);
219 EXPORT_SYMBOL_GPL(xfrm_inner_extract_output
);