This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / net / ipv6 / xfrm6_mode_tunnel.c

diff --git a/net/ipv6/xfrm6_mode_tunnel.c b/net/ipv6/xfrm6_mode_tunnel.c
new file mode 100644 (file)
index 0000000..8af79be
--- /dev/null
+++ b/net/ipv6/xfrm6_mode_tunnel.c
@@ -0,0 +1,121 @@
+/*
+ * xfrm6_mode_tunnel.c - Tunnel mode encapsulation for IPv6.
+ *
+ * Copyright (C) 2002 USAGI/WIDE Project
+ * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/stringify.h>
+#include <net/dsfield.h>
+#include <net/dst.h>
+#include <net/inet_ecn.h>
+#include <net/ipv6.h>
+#include <net/xfrm.h>
+
+static inline void ipip6_ecn_decapsulate(struct sk_buff *skb)
+{
+       struct ipv6hdr *outer_iph = skb->nh.ipv6h;
+       struct ipv6hdr *inner_iph = skb->h.ipv6h;
+
+       if (INET_ECN_is_ce(ipv6_get_dsfield(outer_iph)))
+               IP6_ECN_set_ce(inner_iph);
+}
+
+/* Add encapsulation header.
+ *
+ * The top IP header will be constructed per RFC 2401.  The following fields
+ * in it shall be filled in by x->type->output:
+ *     payload_len
+ *
+ * On exit, skb->h will be set to the start of the encapsulation header to be
+ * filled in by x->type->output and skb->nh will be set to the nextheader field
+ * of the extension header directly preceding the encapsulation header, or in
+ * its absence, that of the top IP header.  The value of skb->data will always
+ * point to the top IP header.
+ */
+static int xfrm6_tunnel_output(struct sk_buff *skb)
+{
+       struct dst_entry *dst = skb->dst;
+       struct xfrm_state *x = dst->xfrm;
+       struct ipv6hdr *iph, *top_iph;
+       int dsfield;
+
+       skb_push(skb, x->props.header_len);
+       iph = skb->nh.ipv6h;
+
+       skb->nh.raw = skb->data;
+       top_iph = skb->nh.ipv6h;
+       skb->nh.raw = &top_iph->nexthdr;
+       skb->h.ipv6h = top_iph + 1;
+
+       top_iph->version = 6;
+       top_iph->priority = iph->priority;
+       top_iph->flow_lbl[0] = iph->flow_lbl[0];
+       top_iph->flow_lbl[1] = iph->flow_lbl[1];
+       top_iph->flow_lbl[2] = iph->flow_lbl[2];
+       dsfield = ipv6_get_dsfield(top_iph);
+       dsfield = INET_ECN_encapsulate(dsfield, dsfield);
+       if (x->props.flags & XFRM_STATE_NOECN)
+               dsfield &= ~INET_ECN_MASK;
+       ipv6_change_dsfield(top_iph, 0, dsfield);
+       top_iph->nexthdr = IPPROTO_IPV6; 
+       top_iph->hop_limit = dst_metric(dst->child, RTAX_HOPLIMIT);
+       ipv6_addr_copy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr);
+       ipv6_addr_copy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr);
+       return 0;
+}
+
+static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+       int err = -EINVAL;
+
+       if (skb->nh.raw[IP6CB(skb)->nhoff] != IPPROTO_IPV6)
+               goto out;
+       if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
+               goto out;
+
+       if (skb_cloned(skb) &&
+           (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
+               goto out;
+
+       if (x->props.flags & XFRM_STATE_DECAP_DSCP)
+               ipv6_copy_dscp(skb->nh.ipv6h, skb->h.ipv6h);
+       if (!(x->props.flags & XFRM_STATE_NOECN))
+               ipip6_ecn_decapsulate(skb);
+       skb->mac.raw = memmove(skb->data - skb->mac_len,
+                              skb->mac.raw, skb->mac_len);
+       skb->nh.raw = skb->data;
+       err = 0;
+
+out:
+       return err;
+}
+
+static struct xfrm_mode xfrm6_tunnel_mode = {
+       .input = xfrm6_tunnel_input,
+       .output = xfrm6_tunnel_output,
+       .owner = THIS_MODULE,
+       .encap = XFRM_MODE_TUNNEL,
+};
+
+static int __init xfrm6_tunnel_init(void)
+{
+       return xfrm_register_mode(&xfrm6_tunnel_mode, AF_INET6);
+}
+
+static void __exit xfrm6_tunnel_exit(void)
+{
+       int err;
+
+       err = xfrm_unregister_mode(&xfrm6_tunnel_mode, AF_INET6);
+       BUG_ON(err);
+}
+
+module_init(xfrm6_tunnel_init);
+module_exit(xfrm6_tunnel_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TUNNEL);