* xfrm6_output.c - Common IPsec encapsulation code for IPv6.
* Copyright (C) 2002 USAGI/WIDE Project
* Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
- *
+ *
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
+#include <linux/if_ether.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
#include <linux/skbuff.h>
-#include <linux/spinlock.h>
#include <linux/icmpv6.h>
-#include <net/dsfield.h>
-#include <net/inet_ecn.h>
+#include <linux/netfilter_ipv6.h>
+#include <net/dst.h>
#include <net/ipv6.h>
#include <net/xfrm.h>
-/* Add encapsulation header.
- *
- * In transport mode, the IP header and mutable extension headers 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:
- * 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 void xfrm6_encap(struct sk_buff *skb)
+int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
+ u8 **prevhdr)
{
- 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;
-
- if (!x->props.mode) {
- u8 *prevhdr;
- int hdr_len;
-
- hdr_len = ip6_find_1stfragopt(skb, &prevhdr);
- skb->nh.raw = prevhdr - x->props.header_len;
- skb->h.raw = skb->data + hdr_len;
- memmove(skb->data, iph, hdr_len);
- return;
- }
-
- 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 ip6_find_1stfragopt(skb, prevhdr);
}
+EXPORT_SYMBOL(xfrm6_find_1stfragopt);
+
static int xfrm6_tunnel_check_size(struct sk_buff *skb)
{
int mtu, ret = 0;
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
- if (skb->len > mtu) {
+ if (!skb->local_df && skb->len > mtu) {
+ skb->dev = dst->dev;
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
ret = -EMSGSIZE;
}
return ret;
}
-int xfrm6_output(struct sk_buff *skb)
+int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
{
- struct dst_entry *dst = skb->dst;
- struct xfrm_state *x = dst->xfrm;
int err;
-
- if (skb->ip_summed == CHECKSUM_HW) {
- err = skb_checksum_help(skb, 0);
- if (err)
- goto error_nolock;
- }
-
- if (x->props.mode) {
- err = xfrm6_tunnel_check_size(skb);
- if (err)
- goto error_nolock;
- }
- spin_lock_bh(&x->lock);
- err = xfrm_state_check(x, skb);
+ err = xfrm6_tunnel_check_size(skb);
if (err)
- goto error;
+ return err;
- xfrm6_encap(skb);
+ XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
- err = x->type->output(x, skb);
+ return xfrm6_extract_header(skb);
+}
+
+int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
+{
+ int err;
+
+ err = xfrm_inner_extract_output(x, skb);
if (err)
- goto error;
+ return err;
- x->curlft.bytes += skb->len;
- x->curlft.packets++;
+ memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
+#ifdef CONFIG_NETFILTER
+ IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
+#endif
- spin_unlock_bh(&x->lock);
+ skb->protocol = htons(ETH_P_IPV6);
- skb->nh.raw = skb->data;
-
- if (!(skb->dst = dst_pop(dst))) {
- err = -EHOSTUNREACH;
- goto error_nolock;
- }
- err = NET_XMIT_BYPASS;
-
-out_exit:
- return err;
-error:
- spin_unlock_bh(&x->lock);
-error_nolock:
- kfree_skb(skb);
- goto out_exit;
+ return x->outer_mode->output2(x, skb);
+}
+EXPORT_SYMBOL(xfrm6_prepare_output);
+
+static int xfrm6_output_finish(struct sk_buff *skb)
+{
+#ifdef CONFIG_NETFILTER
+ IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
+#endif
+
+ skb->protocol = htons(ETH_P_IPV6);
+ return xfrm_output(skb);
+}
+
+int xfrm6_output(struct sk_buff *skb)
+{
+ return NF_HOOK(PF_INET6, NF_INET_POST_ROUTING, skb, NULL, skb->dst->dev,
+ xfrm6_output_finish);
}