96 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			96 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * xfrm6_output.c - Common IPsec encapsulation code for IPv6.
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 * Copyright (C) 2002 USAGI/WIDE Project
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 * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
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 *
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 * This program is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU General Public License
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 * as published by the Free Software Foundation; either version
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 * 2 of the License, or (at your option) any later version.
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 */
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#include <linux/if_ether.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/skbuff.h>
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#include <linux/icmpv6.h>
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#include <linux/netfilter_ipv6.h>
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#include <net/dst.h>
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#include <net/ipv6.h>
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#include <net/xfrm.h>
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int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
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			  u8 **prevhdr)
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{
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	return ip6_find_1stfragopt(skb, prevhdr);
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}
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EXPORT_SYMBOL(xfrm6_find_1stfragopt);
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static int xfrm6_tunnel_check_size(struct sk_buff *skb)
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{
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	int mtu, ret = 0;
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	struct dst_entry *dst = skb_dst(skb);
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	mtu = dst_mtu(dst);
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	if (mtu < IPV6_MIN_MTU)
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		mtu = IPV6_MIN_MTU;
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	if (!skb->local_df && skb->len > mtu) {
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		skb->dev = dst->dev;
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		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
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		ret = -EMSGSIZE;
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	}
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	return ret;
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}
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int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
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{
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	int err;
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	err = xfrm6_tunnel_check_size(skb);
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	if (err)
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		return err;
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	XFRM_MODE_SKB_CB(skb)->protocol = ipv6_hdr(skb)->nexthdr;
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	return xfrm6_extract_header(skb);
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}
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int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
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{
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	int err;
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	err = xfrm_inner_extract_output(x, skb);
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	if (err)
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		return err;
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	memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
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#ifdef CONFIG_NETFILTER
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	IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
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#endif
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	skb->protocol = htons(ETH_P_IPV6);
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	skb->local_df = 1;
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	return x->outer_mode->output2(x, skb);
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}
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EXPORT_SYMBOL(xfrm6_prepare_output);
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static int xfrm6_output_finish(struct sk_buff *skb)
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{
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#ifdef CONFIG_NETFILTER
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	IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
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#endif
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	skb->protocol = htons(ETH_P_IPV6);
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	return xfrm_output(skb);
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}
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int xfrm6_output(struct sk_buff *skb)
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{
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	return NF_HOOK(PF_INET6, NF_INET_POST_ROUTING, skb, NULL, skb_dst(skb)->dev,
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		       xfrm6_output_finish);
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}
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