Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
[linux/fpc-iii.git] / net / xfrm / xfrm_output.c
blob68ada2ca4b60707ac70b45aa6f0a9ea142a9dd16
1 /*
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>
19 #include <net/dst.h>
20 #include <net/xfrm.h>
22 static int xfrm_output2(struct sock *sk, 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)
28 - skb_headroom(skb);
29 int ntail = dst->dev->needed_tailroom - skb_tailroom(skb);
31 if (nhead <= 0) {
32 if (ntail <= 0)
33 return 0;
34 nhead = 0;
35 } else if (ntail < 0)
36 ntail = 0;
38 return pskb_expand_head(skb, nhead, ntail, GFP_ATOMIC);
41 /* Children define the path of the packet through the
42 * Linux networking. Thus, destinations are stackable.
45 static struct dst_entry *skb_dst_pop(struct sk_buff *skb)
47 struct dst_entry *child = dst_clone(skb_dst(skb)->child);
49 skb_dst_drop(skb);
50 return child;
53 static int xfrm_output_one(struct sk_buff *skb, int err)
55 struct dst_entry *dst = skb_dst(skb);
56 struct xfrm_state *x = dst->xfrm;
57 struct net *net = xs_net(x);
59 if (err <= 0)
60 goto resume;
62 do {
63 err = xfrm_skb_check_space(skb);
64 if (err) {
65 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
66 goto error_nolock;
69 err = x->outer_mode->output(x, skb);
70 if (err) {
71 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEMODEERROR);
72 goto error_nolock;
75 spin_lock_bh(&x->lock);
77 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
78 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEINVALID);
79 err = -EINVAL;
80 goto error;
83 err = xfrm_state_check_expire(x);
84 if (err) {
85 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEEXPIRED);
86 goto error;
89 err = x->repl->overflow(x, skb);
90 if (err) {
91 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATESEQERROR);
92 goto error;
95 x->curlft.bytes += skb->len;
96 x->curlft.packets++;
98 spin_unlock_bh(&x->lock);
100 skb_dst_force(skb);
102 err = x->type->output(x, skb);
103 if (err == -EINPROGRESS)
104 goto out;
106 resume:
107 if (err) {
108 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEPROTOERROR);
109 goto error_nolock;
112 dst = skb_dst_pop(skb);
113 if (!dst) {
114 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
115 err = -EHOSTUNREACH;
116 goto error_nolock;
118 skb_dst_set(skb, dst);
119 x = dst->xfrm;
120 } while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL));
122 return 0;
124 error:
125 spin_unlock_bh(&x->lock);
126 error_nolock:
127 kfree_skb(skb);
128 out:
129 return err;
132 int xfrm_output_resume(struct sk_buff *skb, int err)
134 while (likely((err = xfrm_output_one(skb, err)) == 0)) {
135 nf_reset(skb);
137 err = skb_dst(skb)->ops->local_out(skb);
138 if (unlikely(err != 1))
139 goto out;
141 if (!skb_dst(skb)->xfrm)
142 return dst_output(skb);
144 err = nf_hook(skb_dst(skb)->ops->family,
145 NF_INET_POST_ROUTING, skb->sk, skb,
146 NULL, skb_dst(skb)->dev, xfrm_output2);
147 if (unlikely(err != 1))
148 goto out;
151 if (err == -EINPROGRESS)
152 err = 0;
154 out:
155 return err;
157 EXPORT_SYMBOL_GPL(xfrm_output_resume);
159 static int xfrm_output2(struct sock *sk, struct sk_buff *skb)
161 return xfrm_output_resume(skb, 1);
164 static int xfrm_output_gso(struct sock *sk, struct sk_buff *skb)
166 struct sk_buff *segs;
168 segs = skb_gso_segment(skb, 0);
169 kfree_skb(skb);
170 if (IS_ERR(segs))
171 return PTR_ERR(segs);
172 if (segs == NULL)
173 return -EINVAL;
175 do {
176 struct sk_buff *nskb = segs->next;
177 int err;
179 segs->next = NULL;
180 err = xfrm_output2(sk, segs);
182 if (unlikely(err)) {
183 kfree_skb_list(nskb);
184 return err;
187 segs = nskb;
188 } while (segs);
190 return 0;
193 int xfrm_output(struct sock *sk, struct sk_buff *skb)
195 struct net *net = dev_net(skb_dst(skb)->dev);
196 int err;
198 if (skb_is_gso(skb))
199 return xfrm_output_gso(sk, skb);
201 if (skb->ip_summed == CHECKSUM_PARTIAL) {
202 err = skb_checksum_help(skb);
203 if (err) {
204 XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
205 kfree_skb(skb);
206 return err;
210 return xfrm_output2(sk, skb);
212 EXPORT_SYMBOL_GPL(xfrm_output);
214 int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb)
216 struct xfrm_mode *inner_mode;
217 if (x->sel.family == AF_UNSPEC)
218 inner_mode = xfrm_ip2inner_mode(x,
219 xfrm_af2proto(skb_dst(skb)->ops->family));
220 else
221 inner_mode = x->inner_mode;
223 if (inner_mode == NULL)
224 return -EAFNOSUPPORT;
225 return inner_mode->afinfo->extract_output(x, skb);
227 EXPORT_SYMBOL_GPL(xfrm_inner_extract_output);
229 void xfrm_local_error(struct sk_buff *skb, int mtu)
231 unsigned int proto;
232 struct xfrm_state_afinfo *afinfo;
234 if (skb->protocol == htons(ETH_P_IP))
235 proto = AF_INET;
236 else if (skb->protocol == htons(ETH_P_IPV6))
237 proto = AF_INET6;
238 else
239 return;
241 afinfo = xfrm_state_get_afinfo(proto);
242 if (!afinfo)
243 return;
245 afinfo->local_error(skb, mtu);
246 xfrm_state_put_afinfo(afinfo);
248 EXPORT_SYMBOL_GPL(xfrm_local_error);