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)
30 return pskb_expand_head(skb, nhead, 0, GFP_ATOMIC);
32 /* Check tail too... */
36 static int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb)
38 int err = xfrm_state_check_expire(x);
41 err = xfrm_state_check_space(x, skb);
46 static int xfrm_output_one(struct sk_buff *skb, int err)
48 struct dst_entry *dst = skb->dst;
49 struct xfrm_state *x = dst->xfrm;
55 err = x->outer_mode->output(x, skb);
59 spin_lock_bh(&x->lock);
60 err = xfrm_state_check(x, skb);
64 if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
65 XFRM_SKB_CB(skb)->seq = ++x->replay.oseq;
66 if (xfrm_aevent_is_on())
67 xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
70 x->curlft.bytes += skb->len;
73 spin_unlock_bh(&x->lock);
75 err = x->type->output(x, skb);
81 if (!(skb->dst = dst_pop(dst))) {
87 } while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL));
94 spin_unlock_bh(&x->lock);
100 int xfrm_output_resume(struct sk_buff *skb, int err)
102 while (likely((err = xfrm_output_one(skb, err)) == 0)) {
103 struct xfrm_state *x;
107 err = skb->dst->ops->local_out(skb);
108 if (unlikely(err != 1))
113 return dst_output(skb);
115 err = nf_hook(x->inner_mode->afinfo->family,
116 x->inner_mode->afinfo->nf_post_routing, skb,
117 NULL, skb->dst->dev, xfrm_output2);
118 if (unlikely(err != 1))
122 if (err == -EINPROGRESS)
128 EXPORT_SYMBOL_GPL(xfrm_output_resume);
130 static int xfrm_output2(struct sk_buff *skb)
132 return xfrm_output_resume(skb, 1);
135 static int xfrm_output_gso(struct sk_buff *skb)
137 struct sk_buff *segs;
139 segs = skb_gso_segment(skb, 0);
141 if (unlikely(IS_ERR(segs)))
142 return PTR_ERR(segs);
145 struct sk_buff *nskb = segs->next;
149 err = xfrm_output2(segs);
152 while ((segs = nskb)) {
166 int xfrm_output(struct sk_buff *skb)
171 return xfrm_output_gso(skb);
173 if (skb->ip_summed == CHECKSUM_PARTIAL) {
174 err = skb_checksum_help(skb);
181 return xfrm_output2(skb);
183 EXPORT_SYMBOL_GPL(xfrm_output);