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	 9bbc768aa9
			
		
	
	
		9bbc768aa9
		
	
	
	
	
		
			
			The semantic patch that was used: // <smpl> @@ @@ (NF_HOOK |NF_HOOK_COND |nf_hook )( -PF_INET, +NFPROTO_IPV4, ...) // </smpl> Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
		
			
				
	
	
		
			93 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * xfrm4_output.c - Common IPsec encapsulation code for IPv4.
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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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| 
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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/netfilter_ipv4.h>
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| #include <net/dst.h>
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| #include <net/ip.h>
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| #include <net/xfrm.h>
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| #include <net/icmp.h>
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| 
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| static int xfrm4_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;
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| 
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| 	if (IPCB(skb)->flags & IPSKB_XFRM_TUNNEL_SIZE)
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| 		goto out;
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| 
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| 	if (!(ip_hdr(skb)->frag_off & htons(IP_DF)) || skb->local_df)
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| 		goto out;
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| 
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| 	dst = skb_dst(skb);
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| 	mtu = dst_mtu(dst);
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| 	if (skb->len > mtu) {
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| 		icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
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| 		ret = -EMSGSIZE;
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| 	}
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| out:
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| 	return ret;
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| }
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| 
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| int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb)
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| {
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| 	int err;
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| 
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| 	err = xfrm4_tunnel_check_size(skb);
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| 	if (err)
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| 		return err;
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| 
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| 	XFRM_MODE_SKB_CB(skb)->protocol = ip_hdr(skb)->protocol;
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| 
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| 	return xfrm4_extract_header(skb);
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| }
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| 
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| int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
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| {
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| 	int err;
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| 
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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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| 
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| 	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
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| 	IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED;
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| 
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| 	skb->protocol = htons(ETH_P_IP);
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| 
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| 	return x->outer_mode->output2(x, skb);
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| }
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| EXPORT_SYMBOL(xfrm4_prepare_output);
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| 
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| static int xfrm4_output_finish(struct sk_buff *skb)
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| {
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| #ifdef CONFIG_NETFILTER
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| 	if (!skb_dst(skb)->xfrm) {
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| 		IPCB(skb)->flags |= IPSKB_REROUTED;
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| 		return dst_output(skb);
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| 	}
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| 
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| 	IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
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| #endif
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| 
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| 	skb->protocol = htons(ETH_P_IP);
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| 	return xfrm_output(skb);
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| }
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| 
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| int xfrm4_output(struct sk_buff *skb)
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| {
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| 	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, skb,
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| 			    NULL, skb_dst(skb)->dev, xfrm4_output_finish,
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| 			    !(IPCB(skb)->flags & IPSKB_REROUTED));
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| }
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