 1c32c5ad6f
			
		
	
	
	1c32c5ad6f
	
	
	
		
			
			This patch adds the helper ip_make_skb which is like ip_append_data and ip_push_pending_frames all rolled into one, except that it does not send the skb produced. The sending part is carried out by ip_send_skb, which the transport protocol can call after it has tweaked the skb. It is meant to be called in cases where corking is not used should have a one-to-one correspondence to sendmsg. This patch also adds the helper ip_finish_skb which is meant to be replace ip_push_pending_frames when corking is required. Previously the protocol stack would peek at the socket write queue and add its header to the first packet. With ip_finish_skb, the protocol stack can directly operate on the final skb instead, just like the non-corking case with ip_make_skb. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			450 lines
		
	
	
	
		
			13 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			450 lines
		
	
	
	
		
			13 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * INET		An implementation of the TCP/IP protocol suite for the LINUX
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|  *		operating system.  INET is implemented using the  BSD Socket
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|  *		interface as the means of communication with the user level.
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|  *
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|  *		Definitions for the IP module.
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|  *
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|  * Version:	@(#)ip.h	1.0.2	05/07/93
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|  *
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|  * Authors:	Ross Biro
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|  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
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|  *		Alan Cox, <gw4pts@gw4pts.ampr.org>
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|  *
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|  * Changes:
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|  *		Mike McLagan    :       Routing by source
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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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| #ifndef _IP_H
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| #define _IP_H
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| 
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| #include <linux/types.h>
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| #include <linux/ip.h>
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| #include <linux/in.h>
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| #include <linux/skbuff.h>
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| 
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| #include <net/inet_sock.h>
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| #include <net/snmp.h>
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| #include <net/flow.h>
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| 
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| struct sock;
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| 
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| struct inet_skb_parm {
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| 	struct ip_options	opt;		/* Compiled IP options		*/
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| 	unsigned char		flags;
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| 
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| #define IPSKB_FORWARDED		1
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| #define IPSKB_XFRM_TUNNEL_SIZE	2
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| #define IPSKB_XFRM_TRANSFORMED	4
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| #define IPSKB_FRAG_COMPLETE	8
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| #define IPSKB_REROUTED		16
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| };
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| 
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| static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
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| {
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| 	return ip_hdr(skb)->ihl * 4;
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| }
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| 
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| struct ipcm_cookie {
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| 	__be32			addr;
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| 	int			oif;
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| 	struct ip_options	*opt;
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| 	__u8			tx_flags;
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| };
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| 
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| #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
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| 
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| struct ip_ra_chain {
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| 	struct ip_ra_chain __rcu *next;
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| 	struct sock		*sk;
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| 	union {
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| 		void			(*destructor)(struct sock *);
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| 		struct sock		*saved_sk;
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| 	};
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| 	struct rcu_head		rcu;
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| };
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| 
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| extern struct ip_ra_chain __rcu *ip_ra_chain;
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| 
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| /* IP flags. */
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| #define IP_CE		0x8000		/* Flag: "Congestion"		*/
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| #define IP_DF		0x4000		/* Flag: "Don't Fragment"	*/
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| #define IP_MF		0x2000		/* Flag: "More Fragments"	*/
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| #define IP_OFFSET	0x1FFF		/* "Fragment Offset" part	*/
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| 
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| #define IP_FRAG_TIME	(30 * HZ)		/* fragment lifetime	*/
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| 
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| struct msghdr;
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| struct net_device;
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| struct packet_type;
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| struct rtable;
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| struct sockaddr;
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| 
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| extern int		igmp_mc_proc_init(void);
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| 
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| /*
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|  *	Functions provided by ip.c
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|  */
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| 
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| extern int		ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk,
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| 					      __be32 saddr, __be32 daddr,
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| 					      struct ip_options *opt);
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| extern int		ip_rcv(struct sk_buff *skb, struct net_device *dev,
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| 			       struct packet_type *pt, struct net_device *orig_dev);
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| extern int		ip_local_deliver(struct sk_buff *skb);
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| extern int		ip_mr_input(struct sk_buff *skb);
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| extern int		ip_output(struct sk_buff *skb);
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| extern int		ip_mc_output(struct sk_buff *skb);
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| extern int		ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
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| extern int		ip_do_nat(struct sk_buff *skb);
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| extern void		ip_send_check(struct iphdr *ip);
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| extern int		__ip_local_out(struct sk_buff *skb);
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| extern int		ip_local_out(struct sk_buff *skb);
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| extern int		ip_queue_xmit(struct sk_buff *skb);
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| extern void		ip_init(void);
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| extern int		ip_append_data(struct sock *sk,
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| 				       int getfrag(void *from, char *to, int offset, int len,
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| 						   int odd, struct sk_buff *skb),
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| 				void *from, int len, int protolen,
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| 				struct ipcm_cookie *ipc,
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| 				struct rtable **rt,
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| 				unsigned int flags);
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| extern int		ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb);
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| extern ssize_t		ip_append_page(struct sock *sk, struct page *page,
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| 				int offset, size_t size, int flags);
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| extern struct sk_buff  *__ip_make_skb(struct sock *sk,
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| 				      struct sk_buff_head *queue,
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| 				      struct inet_cork *cork);
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| extern int		ip_send_skb(struct sk_buff *skb);
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| extern int		ip_push_pending_frames(struct sock *sk);
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| extern void		ip_flush_pending_frames(struct sock *sk);
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| extern struct sk_buff  *ip_make_skb(struct sock *sk,
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| 				    int getfrag(void *from, char *to, int offset, int len,
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| 						int odd, struct sk_buff *skb),
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| 				    void *from, int length, int transhdrlen,
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| 				    struct ipcm_cookie *ipc,
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| 				    struct rtable **rtp,
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| 				    unsigned int flags);
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| 
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| static inline struct sk_buff *ip_finish_skb(struct sock *sk)
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| {
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| 	return __ip_make_skb(sk, &sk->sk_write_queue, &inet_sk(sk)->cork);
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| }
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| 
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| /* datagram.c */
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| extern int		ip4_datagram_connect(struct sock *sk, 
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| 					     struct sockaddr *uaddr, int addr_len);
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| 
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| /*
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|  *	Map a multicast IP onto multicast MAC for type Token Ring.
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|  *      This conforms to RFC1469 Option 2 Multicasting i.e.
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|  *      using a functional address to transmit / receive 
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|  *      multicast packets.
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|  */
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| 
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| static inline void ip_tr_mc_map(__be32 addr, char *buf)
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| {
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| 	buf[0]=0xC0;
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| 	buf[1]=0x00;
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| 	buf[2]=0x00;
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| 	buf[3]=0x04;
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| 	buf[4]=0x00;
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| 	buf[5]=0x00;
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| }
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| 
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| struct ip_reply_arg {
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| 	struct kvec iov[1];   
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| 	int	    flags;
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| 	__wsum 	    csum;
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| 	int	    csumoffset; /* u16 offset of csum in iov[0].iov_base */
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| 				/* -1 if not needed */ 
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| 	int	    bound_dev_if;
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| }; 
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| 
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| #define IP_REPLY_ARG_NOSRCCHECK 1
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| 
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| static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg)
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| {
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| 	return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0;
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| }
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| 
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| void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *arg,
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| 		   unsigned int len); 
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| 
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| struct ipv4_config {
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| 	int	log_martians;
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| 	int	no_pmtu_disc;
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| };
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| 
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| extern struct ipv4_config ipv4_config;
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| #define IP_INC_STATS(net, field)	SNMP_INC_STATS64((net)->mib.ip_statistics, field)
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| #define IP_INC_STATS_BH(net, field)	SNMP_INC_STATS64_BH((net)->mib.ip_statistics, field)
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| #define IP_ADD_STATS(net, field, val)	SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val)
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| #define IP_ADD_STATS_BH(net, field, val) SNMP_ADD_STATS64_BH((net)->mib.ip_statistics, field, val)
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| #define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val)
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| #define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
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| #define NET_INC_STATS(net, field)	SNMP_INC_STATS((net)->mib.net_statistics, field)
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| #define NET_INC_STATS_BH(net, field)	SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
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| #define NET_INC_STATS_USER(net, field) 	SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
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| #define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
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| #define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)
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| 
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| extern unsigned long snmp_fold_field(void __percpu *mib[], int offt);
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| #if BITS_PER_LONG==32
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| extern u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t sync_off);
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| #else
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| static inline u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_off)
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| {
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| 	return snmp_fold_field(mib, offt);
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| }
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| #endif
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| extern int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align);
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| extern void snmp_mib_free(void __percpu *ptr[2]);
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| 
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| extern struct local_ports {
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| 	seqlock_t	lock;
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| 	int		range[2];
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| } sysctl_local_ports;
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| extern void inet_get_local_port_range(int *low, int *high);
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| 
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| extern unsigned long *sysctl_local_reserved_ports;
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| static inline int inet_is_reserved_local_port(int port)
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| {
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| 	return test_bit(port, sysctl_local_reserved_ports);
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| }
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| 
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| extern int sysctl_ip_nonlocal_bind;
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| 
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| extern struct ctl_path net_core_path[];
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| extern struct ctl_path net_ipv4_ctl_path[];
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| 
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| /* From inetpeer.c */
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| extern int inet_peer_threshold;
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| extern int inet_peer_minttl;
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| extern int inet_peer_maxttl;
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| extern int inet_peer_gc_mintime;
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| extern int inet_peer_gc_maxtime;
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| 
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| /* From ip_output.c */
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| extern int sysctl_ip_dynaddr;
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| 
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| extern void ipfrag_init(void);
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| 
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| extern void ip_static_sysctl_init(void);
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| 
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| #ifdef CONFIG_INET
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| #include <net/dst.h>
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| 
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| /* The function in 2.2 was invalid, producing wrong result for
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|  * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */
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| static inline
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| int ip_decrease_ttl(struct iphdr *iph)
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| {
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| 	u32 check = (__force u32)iph->check;
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| 	check += (__force u32)htons(0x0100);
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| 	iph->check = (__force __sum16)(check + (check>=0xFFFF));
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| 	return --iph->ttl;
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| }
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| 
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| static inline
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| int ip_dont_fragment(struct sock *sk, struct dst_entry *dst)
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| {
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| 	return  inet_sk(sk)->pmtudisc == IP_PMTUDISC_DO ||
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| 		(inet_sk(sk)->pmtudisc == IP_PMTUDISC_WANT &&
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| 		 !(dst_metric_locked(dst, RTAX_MTU)));
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| }
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| 
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| extern void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more);
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| 
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| static inline void ip_select_ident(struct iphdr *iph, struct dst_entry *dst, struct sock *sk)
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| {
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| 	if (iph->frag_off & htons(IP_DF)) {
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| 		/* This is only to work around buggy Windows95/2000
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| 		 * VJ compression implementations.  If the ID field
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| 		 * does not change, they drop every other packet in
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| 		 * a TCP stream using header compression.
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| 		 */
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| 		iph->id = (sk && inet_sk(sk)->inet_daddr) ?
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| 					htons(inet_sk(sk)->inet_id++) : 0;
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| 	} else
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| 		__ip_select_ident(iph, dst, 0);
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| }
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| 
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| static inline void ip_select_ident_more(struct iphdr *iph, struct dst_entry *dst, struct sock *sk, int more)
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| {
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| 	if (iph->frag_off & htons(IP_DF)) {
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| 		if (sk && inet_sk(sk)->inet_daddr) {
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| 			iph->id = htons(inet_sk(sk)->inet_id);
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| 			inet_sk(sk)->inet_id += 1 + more;
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| 		} else
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| 			iph->id = 0;
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| 	} else
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| 		__ip_select_ident(iph, dst, more);
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| }
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| 
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| /*
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|  *	Map a multicast IP onto multicast MAC for type ethernet.
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|  */
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| 
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| static inline void ip_eth_mc_map(__be32 naddr, char *buf)
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| {
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| 	__u32 addr=ntohl(naddr);
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| 	buf[0]=0x01;
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| 	buf[1]=0x00;
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| 	buf[2]=0x5e;
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| 	buf[5]=addr&0xFF;
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| 	addr>>=8;
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| 	buf[4]=addr&0xFF;
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| 	addr>>=8;
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| 	buf[3]=addr&0x7F;
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| }
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| 
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| /*
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|  *	Map a multicast IP onto multicast MAC for type IP-over-InfiniBand.
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|  *	Leave P_Key as 0 to be filled in by driver.
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|  */
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| 
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| static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf)
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| {
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| 	__u32 addr;
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| 	unsigned char scope = broadcast[5] & 0xF;
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| 
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| 	buf[0]  = 0;		/* Reserved */
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| 	buf[1]  = 0xff;		/* Multicast QPN */
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| 	buf[2]  = 0xff;
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| 	buf[3]  = 0xff;
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| 	addr    = ntohl(naddr);
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| 	buf[4]  = 0xff;
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| 	buf[5]  = 0x10 | scope;	/* scope from broadcast address */
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| 	buf[6]  = 0x40;		/* IPv4 signature */
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| 	buf[7]  = 0x1b;
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| 	buf[8]  = broadcast[8];		/* P_Key */
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| 	buf[9]  = broadcast[9];
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| 	buf[10] = 0;
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| 	buf[11] = 0;
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| 	buf[12] = 0;
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| 	buf[13] = 0;
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| 	buf[14] = 0;
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| 	buf[15] = 0;
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| 	buf[19] = addr & 0xff;
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| 	addr  >>= 8;
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| 	buf[18] = addr & 0xff;
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| 	addr  >>= 8;
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| 	buf[17] = addr & 0xff;
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| 	addr  >>= 8;
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| 	buf[16] = addr & 0x0f;
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| }
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| 
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| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
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| #include <linux/ipv6.h>
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| #endif
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| 
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| static __inline__ void inet_reset_saddr(struct sock *sk)
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| {
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| 	inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0;
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| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
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| 	if (sk->sk_family == PF_INET6) {
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| 		struct ipv6_pinfo *np = inet6_sk(sk);
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| 
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| 		memset(&np->saddr, 0, sizeof(np->saddr));
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| 		memset(&np->rcv_saddr, 0, sizeof(np->rcv_saddr));
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| 	}
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| #endif
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| }
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| 
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| #endif
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| 
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| static inline int sk_mc_loop(struct sock *sk)
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| {
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| 	if (!sk)
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| 		return 1;
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| 	switch (sk->sk_family) {
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| 	case AF_INET:
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| 		return inet_sk(sk)->mc_loop;
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| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
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| 	case AF_INET6:
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| 		return inet6_sk(sk)->mc_loop;
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| #endif
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| 	}
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| 	WARN_ON(1);
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| 	return 1;
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| }
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| 
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| extern int	ip_call_ra_chain(struct sk_buff *skb);
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| 
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| /*
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|  *	Functions provided by ip_fragment.c
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|  */
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| 
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| enum ip_defrag_users {
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| 	IP_DEFRAG_LOCAL_DELIVER,
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| 	IP_DEFRAG_CALL_RA_CHAIN,
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| 	IP_DEFRAG_CONNTRACK_IN,
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| 	__IP_DEFRAG_CONNTRACK_IN_END	= IP_DEFRAG_CONNTRACK_IN + USHRT_MAX,
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| 	IP_DEFRAG_CONNTRACK_OUT,
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| 	__IP_DEFRAG_CONNTRACK_OUT_END	= IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
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| 	IP_DEFRAG_CONNTRACK_BRIDGE_IN,
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| 	__IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
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| 	IP_DEFRAG_VS_IN,
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| 	IP_DEFRAG_VS_OUT,
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| 	IP_DEFRAG_VS_FWD
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| };
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| 
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| int ip_defrag(struct sk_buff *skb, u32 user);
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| int ip_frag_mem(struct net *net);
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| int ip_frag_nqueues(struct net *net);
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| 
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| /*
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|  *	Functions provided by ip_forward.c
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|  */
 | |
|  
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| extern int ip_forward(struct sk_buff *skb);
 | |
|  
 | |
| /*
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|  *	Functions provided by ip_options.c
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|  */
 | |
|  
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| extern void ip_options_build(struct sk_buff *skb, struct ip_options *opt, __be32 daddr, struct rtable *rt, int is_frag);
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| extern int ip_options_echo(struct ip_options *dopt, struct sk_buff *skb);
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| extern void ip_options_fragment(struct sk_buff *skb);
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| extern int ip_options_compile(struct net *net,
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| 			      struct ip_options *opt, struct sk_buff *skb);
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| extern int ip_options_get(struct net *net, struct ip_options **optp,
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| 			  unsigned char *data, int optlen);
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| extern int ip_options_get_from_user(struct net *net, struct ip_options **optp,
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| 				    unsigned char __user *data, int optlen);
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| extern void ip_options_undo(struct ip_options * opt);
 | |
| extern void ip_forward_options(struct sk_buff *skb);
 | |
| extern int ip_options_rcv_srr(struct sk_buff *skb);
 | |
| 
 | |
| /*
 | |
|  *	Functions provided by ip_sockglue.c
 | |
|  */
 | |
| 
 | |
| extern int	ip_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
 | |
| extern void	ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb);
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| extern int	ip_cmsg_send(struct net *net,
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| 			     struct msghdr *msg, struct ipcm_cookie *ipc);
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| extern int	ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen);
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| extern int	ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen);
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| extern int	compat_ip_setsockopt(struct sock *sk, int level,
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| 			int optname, char __user *optval, unsigned int optlen);
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| extern int	compat_ip_getsockopt(struct sock *sk, int level,
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| 			int optname, char __user *optval, int __user *optlen);
 | |
| extern int	ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *));
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| 
 | |
| extern int 	ip_recv_error(struct sock *sk, struct msghdr *msg, int len);
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| extern void	ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 
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| 			      __be16 port, u32 info, u8 *payload);
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| extern void	ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport,
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| 			       u32 info);
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| 
 | |
| #ifdef CONFIG_PROC_FS
 | |
| extern int ip_misc_proc_init(void);
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| #endif
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| 
 | |
| #endif	/* _IP_H */
 |