 30fff9231f
			
		
	
	
	30fff9231f
	
	
	
		
			
			UDP bind() can be O(N^2) in some pathological cases. Thanks to secondary hash tables, we can make it O(N) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			101 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			101 lines
		
	
	
	
		
			3 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 UDP protocol.
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|  *
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|  * Version:	@(#)udp.h	1.0.2	04/28/93
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|  *
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|  * Author:	Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
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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 _LINUX_UDP_H
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| #define _LINUX_UDP_H
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| 
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| #include <linux/types.h>
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| 
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| struct udphdr {
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| 	__be16	source;
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| 	__be16	dest;
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| 	__be16	len;
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| 	__sum16	check;
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| };
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| 
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| /* UDP socket options */
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| #define UDP_CORK	1	/* Never send partially complete segments */
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| #define UDP_ENCAP	100	/* Set the socket to accept encapsulated packets */
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| 
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| /* UDP encapsulation types */
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| #define UDP_ENCAP_ESPINUDP_NON_IKE	1 /* draft-ietf-ipsec-nat-t-ike-00/01 */
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| #define UDP_ENCAP_ESPINUDP	2 /* draft-ietf-ipsec-udp-encaps-06 */
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| #define UDP_ENCAP_L2TPINUDP	3 /* rfc2661 */
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| 
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| #ifdef __KERNEL__
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| #include <net/inet_sock.h>
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| #include <linux/skbuff.h>
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| #include <net/netns/hash.h>
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| 
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| static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
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| {
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| 	return (struct udphdr *)skb_transport_header(skb);
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| }
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| 
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| #define UDP_HTABLE_SIZE_MIN		(CONFIG_BASE_SMALL ? 128 : 256)
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| 
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| static inline int udp_hashfn(struct net *net, unsigned num, unsigned mask)
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| {
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| 	return (num + net_hash_mix(net)) & mask;
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| }
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| 
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| struct udp_sock {
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| 	/* inet_sock has to be the first member */
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| 	struct inet_sock inet;
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| #define udp_port_hash		inet.sk.__sk_common.skc_u16hashes[0]
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| #define udp_portaddr_hash	inet.sk.__sk_common.skc_u16hashes[1]
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| #define udp_portaddr_node	inet.sk.__sk_common.skc_portaddr_node
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| 	int		 pending;	/* Any pending frames ? */
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| 	unsigned int	 corkflag;	/* Cork is required */
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|   	__u16		 encap_type;	/* Is this an Encapsulation socket? */
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| 	/*
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| 	 * Following member retains the information to create a UDP header
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| 	 * when the socket is uncorked.
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| 	 */
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| 	__u16		 len;		/* total length of pending frames */
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| 	/*
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| 	 * Fields specific to UDP-Lite.
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| 	 */
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| 	__u16		 pcslen;
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| 	__u16		 pcrlen;
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| /* indicator bits used by pcflag: */
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| #define UDPLITE_BIT      0x1  		/* set by udplite proto init function */
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| #define UDPLITE_SEND_CC  0x2  		/* set via udplite setsockopt         */
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| #define UDPLITE_RECV_CC  0x4		/* set via udplite setsocktopt        */
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| 	__u8		 pcflag;        /* marks socket as UDP-Lite if > 0    */
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| 	__u8		 unused[3];
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| 	/*
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| 	 * For encapsulation sockets.
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| 	 */
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| 	int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
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| };
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| 
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| static inline struct udp_sock *udp_sk(const struct sock *sk)
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| {
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| 	return (struct udp_sock *)sk;
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| }
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| 
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| #define udp_portaddr_for_each_entry(__sk, node, list) \
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| 	hlist_nulls_for_each_entry(__sk, node, list, __sk_common.skc_portaddr_node)
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| 
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| #define udp_portaddr_for_each_entry_rcu(__sk, node, list) \
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| 	hlist_nulls_for_each_entry_rcu(__sk, node, list, __sk_common.skc_portaddr_node)
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| 
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| #define IS_UDPLITE(__sk) (udp_sk(__sk)->pcflag)
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| 
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| #endif
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| 
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| #endif	/* _LINUX_UDP_H */
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