* 2 of the License, or (at your option) any later version.
*/
+#include <linux/compiler.h>
+#include <linux/if_ether.h>
+#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
-#include <net/inet_ecn.h>
+#include <linux/netfilter_ipv4.h>
#include <net/ip.h>
#include <net/xfrm.h>
#include <net/icmp.h>
-/* Add encapsulation header.
- *
- * In transport mode, the IP header will be moved forward to make space
- * for the encapsulation header.
- *
- * In tunnel mode, the top IP header will be constructed per RFC 2401.
- * The following fields in it shall be filled in by x->type->output:
- * tot_len
- * check
- *
- * On exit, skb->h will be set to the start of the payload to be processed
- * by x->type->output and skb->nh will be set to the top IP header.
- */
-static void xfrm4_encap(struct sk_buff *skb)
-{
- struct dst_entry *dst = skb->dst;
- struct xfrm_state *x = dst->xfrm;
- struct iphdr *iph, *top_iph;
- int flags;
-
- iph = skb->nh.iph;
- skb->h.ipiph = iph;
-
- skb->nh.raw = skb_push(skb, x->props.header_len);
- top_iph = skb->nh.iph;
-
- if (!x->props.mode) {
- skb->h.raw += iph->ihl*4;
- memmove(top_iph, iph, iph->ihl*4);
- return;
- }
-
- top_iph->ihl = 5;
- top_iph->version = 4;
-
- /* DS disclosed */
- top_iph->tos = INET_ECN_encapsulate(iph->tos, iph->tos);
-
- flags = x->props.flags;
- if (flags & XFRM_STATE_NOECN)
- IP_ECN_clear(top_iph);
-
- top_iph->frag_off = (flags & XFRM_STATE_NOPMTUDISC) ?
- 0 : (iph->frag_off & htons(IP_DF));
- if (!top_iph->frag_off)
- __ip_select_ident(top_iph, dst, 0);
-
- top_iph->ttl = dst_metric(dst->child, RTAX_HOPLIMIT);
-
- top_iph->saddr = x->props.saddr.a4;
- top_iph->daddr = x->id.daddr.a4;
- top_iph->protocol = IPPROTO_IPIP;
-
- memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
-}
-
static int xfrm4_tunnel_check_size(struct sk_buff *skb)
{
int mtu, ret = 0;
return ret;
}
-int xfrm4_output(struct sk_buff *skb)
+static int xfrm4_output_one(struct sk_buff *skb)
{
struct dst_entry *dst = skb->dst;
struct xfrm_state *x = dst->xfrm;
goto error_nolock;
}
- spin_lock_bh(&x->lock);
- err = xfrm_state_check(x, skb);
- if (err)
- goto error;
+ do {
+ spin_lock_bh(&x->lock);
+ err = xfrm_state_check(x, skb);
+ if (err)
+ goto error;
- xfrm4_encap(skb);
+ err = x->mode->output(skb);
+ if (err)
+ goto error;
- err = x->type->output(x, skb);
- if (err)
- goto error;
+ err = x->type->output(x, skb);
+ if (err)
+ goto error;
- x->curlft.bytes += skb->len;
- x->curlft.packets++;
+ x->curlft.bytes += skb->len;
+ x->curlft.packets++;
- spin_unlock_bh(&x->lock);
+ spin_unlock_bh(&x->lock);
- if (!(skb->dst = dst_pop(dst))) {
- err = -EHOSTUNREACH;
- goto error_nolock;
- }
- err = NET_XMIT_BYPASS;
+ if (!(skb->dst = dst_pop(dst))) {
+ err = -EHOSTUNREACH;
+ goto error_nolock;
+ }
+ dst = skb->dst;
+ x = dst->xfrm;
+ } while (x && !x->props.mode);
+
+ IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
+ err = 0;
out_exit:
return err;
kfree_skb(skb);
goto out_exit;
}
+
+static int xfrm4_output_finish2(struct sk_buff *skb)
+{
+ int err;
+
+ while (likely((err = xfrm4_output_one(skb)) == 0)) {
+ nf_reset(skb);
+
+ err = nf_hook(PF_INET, NF_IP_LOCAL_OUT, &skb, NULL,
+ skb->dst->dev, dst_output);
+ if (unlikely(err != 1))
+ break;
+
+ if (!skb->dst->xfrm)
+ return dst_output(skb);
+
+ err = nf_hook(PF_INET, NF_IP_POST_ROUTING, &skb, NULL,
+ skb->dst->dev, xfrm4_output_finish2);
+ if (unlikely(err != 1))
+ break;
+ }
+
+ return err;
+}
+
+static int xfrm4_output_finish(struct sk_buff *skb)
+{
+ struct sk_buff *segs;
+
+#ifdef CONFIG_NETFILTER
+ if (!skb->dst->xfrm) {
+ IPCB(skb)->flags |= IPSKB_REROUTED;
+ return dst_output(skb);
+ }
+#endif
+
+ if (!skb_shinfo(skb)->gso_size)
+ return xfrm4_output_finish2(skb);
+
+ skb->protocol = htons(ETH_P_IP);
+ segs = skb_gso_segment(skb, 0);
+ kfree_skb(skb);
+ if (unlikely(IS_ERR(segs)))
+ return PTR_ERR(segs);
+
+ do {
+ struct sk_buff *nskb = segs->next;
+ int err;
+
+ segs->next = NULL;
+ err = xfrm4_output_finish2(segs);
+
+ if (unlikely(err)) {
+ while ((segs = nskb)) {
+ nskb = segs->next;
+ segs->next = NULL;
+ kfree_skb(segs);
+ }
+ return err;
+ }
+
+ segs = nskb;
+ } while (segs);
+
+ return 0;
+}
+
+int xfrm4_output(struct sk_buff *skb)
+{
+ return NF_HOOK_COND(PF_INET, NF_IP_POST_ROUTING, skb, NULL, skb->dst->dev,
+ xfrm4_output_finish,
+ !(IPCB(skb)->flags & IPSKB_REROUTED));
+}