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diff --git a/src/common/linux_jhash_algo.c b/src/common/linux_jhash_algo.c
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+

+/* jhash.h: Jenkins hash support.

+ *

+ * Copyright (C) 2006. Bob Jenkins ([email protected])

+ *

+ * http://burtleburtle.net/bob/hash/

+ *

+ * These are the credits from Bob's sources:

+ *

+ * lookup3.c, by Bob Jenkins, May 2006, Public Domain.

+ *

+ * These are functions for producing 32-bit hashes for hash table lookup.

+ * hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final()

+ * are externally useful functions.  Routines to test the hash are included

+ * if SELF_TEST is defined.  You can use this free for any purpose.  It's in

+ * the public domain.  It has no warranty.

+ *

+ * Copyright (C) 2009-2010 Jozsef Kadlecsik ([email protected])

+ *

+ * I've modified Bob's hash to be useful in the Linux kernel, and

+ * any bugs present are my fault.

+ * Jozsef

+ */

+

+#include "flowood.h"

+

+/* An arbitrary initial parameter */

+#define JHASH_INITVAL		(0x20180601)  /* flowood��Ŀ������������������ */

+

+

+#ifndef u32

+typedef unsigned int u32;

+#endif

+

+#ifndef __u32

+typedef unsigned int __u32;

+#endif

+

+/* Best hash sizes are of power of two */

+#define jhash_size(n)   ((u32)1<<(n))

+/* Mask the hash value, i.e (value & jhash_mask(n)) instead of (value % n) */

+#define jhash_mask(n)   (jhash_size(n)-1)

+

+

+/**

+ * rol32 - rotate a 32-bit value left

+ * @word: value to rotate

+ * @shift: bits to roll

+ */

+static inline __u32 rol32(__u32 word, unsigned int shift)

+{

+	return (word << shift) | (word >> (32 - shift));

+}

+

+/* __jhash_mix -- mix 3 32-bit values reversibly. */

+#define __jhash_mix(a, b, c)			\

+{						\

+	a -= c;  a ^= rol32(c, 4);  c += b;	\

+	b -= a;  b ^= rol32(a, 6);  a += c;	\

+	c -= b;  c ^= rol32(b, 8);  b += a;	\

+	a -= c;  a ^= rol32(c, 16); c += b;	\

+	b -= a;  b ^= rol32(a, 19); a += c;	\

+	c -= b;  c ^= rol32(b, 4);  b += a;	\

+}

+

+/* __jhash_final - final mixing of 3 32-bit values (a,b,c) into c */

+#define __jhash_final(a, b, c)			\

+{						\

+	c ^= b; c -= rol32(b, 14);		\

+	a ^= c; a -= rol32(c, 11);		\

+	b ^= a; b -= rol32(a, 25);		\

+	c ^= b; c -= rol32(b, 16);		\

+	a ^= c; a -= rol32(c, 4);		\

+	b ^= a; b -= rol32(a, 14);		\

+	c ^= b; c -= rol32(b, 24);		\

+}

+

+#if 0

+/* jhash - hash an arbitrary key

+ * @k: sequence of bytes as key

+ * @length: the length of the key

+ * @initval: the previous hash, or an arbitray value

+ *

+ * The generic version, hashes an arbitrary sequence of bytes.

+ * No alignment or length assumptions are made about the input key.

+ *

+ * Returns the hash value of the key. The result depends on endianness.

+ */

+static inline u32 jhash(const void *key, u32 length, u32 initval)

+{

+	u32 a, b, c;

+	const u8 *k = key;

+

+	/* Set up the internal state */

+	a = b = c = JHASH_INITVAL + length + initval;

+

+	/* All but the last block: affect some 32 bits of (a,b,c) */

+	while (length > 12) {

+		a += __get_unaligned_cpu32(k);

+		b += __get_unaligned_cpu32(k + 4);

+		c += __get_unaligned_cpu32(k + 8);

+		__jhash_mix(a, b, c);

+		length -= 12;

+		k += 12;

+	}

+	/* Last block: affect all 32 bits of (c) */

+	/* All the case statements fall through */

+	switch (length) {

+	case 12: c += (u32)k[11]<<24;

+	case 11: c += (u32)k[10]<<16;

+	case 10: c += (u32)k[9]<<8;

+	case 9:  c += k[8];

+	case 8:  b += (u32)k[7]<<24;

+	case 7:  b += (u32)k[6]<<16;

+	case 6:  b += (u32)k[5]<<8;

+	case 5:  b += k[4];

+	case 4:  a += (u32)k[3]<<24;

+	case 3:  a += (u32)k[2]<<16;

+	case 2:  a += (u32)k[1]<<8;

+	case 1:  a += k[0];

+		 __jhash_final(a, b, c);

+	case 0: /* Nothing left to add */

+		break;

+	}

+

+	return c;

+}

+#endif

+

+/* jhash2 - hash an array of u32's

+ * @k: the key which must be an array of u32's

+ * @length: the number of u32's in the key

+ * @initval: the previous hash, or an arbitray value

+ *

+ * Returns the hash value of the key.

+ */

+static inline u32 jhash2(const u32 *k, u32 length, u32 initval)

+{

+	u32 a, b, c;

+

+	/* Set up the internal state */

+	a = b = c = JHASH_INITVAL + (length<<2) + initval;

+

+	/* Handle most of the key */

+	while (length > 3) {

+		a += k[0];

+		b += k[1];

+		c += k[2];

+		__jhash_mix(a, b, c);

+		length -= 3;

+		k += 3;

+	}

+

+	/* Handle the last 3 u32's: all the case statements fall through */

+	switch (length) {

+	case 3: c += k[2];

+	case 2: b += k[1];

+	case 1: a += k[0];

+		__jhash_final(a, b, c);

+	case 0:	/* Nothing left to add */

+		break;

+	}

+

+	return c;

+}

+

+

+/* jhash_3words - hash exactly 3, 2 or 1 word(s) */

+static inline u32 jhash_3words(u32 a, u32 b, u32 c, u32 initval)

+{

+	a += JHASH_INITVAL;

+	b += JHASH_INITVAL;

+	c += initval;

+

+	__jhash_final(a, b, c);

+

+	return c;

+}

+

+/*

+	NATת�����ͼ������ݰ�ָ�Ƹ���һ������, ������sport_with_no_id_hash����:

+	sport_with_no_id_hash=0: ���ڼ�����Ԫ��HASH,

+	sport_with_no_id_hash=1: ���ڼ������ݰ�ָ��;

+

+	NOTE:

+		����Ԫ��hash����ʱ, ����Ҫ��dir_reverse, 

+		��ΪC2S�����S2C�������ɵ�key����Ԫ��ʵ�ʶ�������һ����,

+		����ѭ���ַ��ΪԴ�Ĺ���, ֻ��dir_reverse��ͬ,

+		C2S��S2C����������һ��, dir_reverse�϶����෴��.	

+*/

+unsigned int flwd_tuple5_hash(const flwd_tuple5_t *tuple5, int sport_with_no_id_hash)

+{

+	unsigned int sip;

+	unsigned int dip;

+	unsigned int hash_val = 0;

+	unsigned short sport; /* ������Ԫ��HASHʱ, ��ȫ����bit; ����ָ����Ϣʱ, ֻ��sport�����8bit�˿�ֵ, ����������id, hash */

+	unsigned short dport;

+

+	if(flwd_likely(FLWD_IP_ADDR_TYPE_V4 == tuple5->addr_type)){

+		sip = tuple5->ippair_v4.sip_net_order;

+		dip = tuple5->ippair_v4.dip_net_order;	

+	}else{

+		sip = tuple5->ippair_v6->sip_net_order.s6_addr32[0]; /* ʹ�����4�ֽ� */

+		dip = tuple5->ippair_v6->dip_net_order.s6_addr32[0]; /* ʹ�����4�ֽ� */

+	}

+

+	if(sport_with_no_id_hash){

+		sport = ntohs(tuple5->sport_net_order) & FLWD_UDP_SPORT_ACTUAL_PORT_MASK; /* ֻ�������Ķ˿�ֵ, ����id��hash�ֶ� */

+	}else{

+		sport = tuple5->sport_net_order;

+	}

+	dport = tuple5->dport_net_order;

+	

+	hash_val = (unsigned int)sport;

+	hash_val |= ((unsigned int)dport << 16);

+	hash_val += JHASH_INITVAL;	

+	

+	__jhash_final(sip, dip, hash_val);

+

+	return hash_val;

+}

+

+

+

+unsigned int __flwd_tuple5_hash(const flwd_tuple5_t *tuple5)

+{

+	unsigned int sip;

+	unsigned int dip;

+	unsigned int port_union;

+	unsigned short sport_no_id_hash; /* ������Ԫ��HASHʱ, ֻ��sport�����8bit�˿�ֵ, ��������id, hash */

+	unsigned short dport;

+

+	if(flwd_likely(FLWD_IP_ADDR_TYPE_V4 == tuple5->addr_type)){

+		if(0 == tuple5->dir_reverse){

+			sip = tuple5->ippair_v4.sip_net_order;

+			dip = tuple5->ippair_v4.dip_net_order;		

+			sport_no_id_hash = ntohs(tuple5->sport_net_order) & FLWD_UDP_SPORT_ACTUAL_PORT_MASK; /* ֻ�������Ķ˿�ֵ, ����id��hash�ֶ� */

+			dport = tuple5->dport_net_order;

+		}else{

+			sip = tuple5->ippair_v4.dip_net_order;

+			dip = tuple5->ippair_v4.sip_net_order;			

+			sport_no_id_hash = ntohs(tuple5->dport_net_order) & FLWD_UDP_SPORT_ACTUAL_PORT_MASK;  /* ֻ�������Ķ˿�ֵ, ����id��hash�ֶ� */

+			dport = tuple5->sport_net_order;

+		}

+	}else{

+		if(0 == tuple5->dir_reverse){

+			sip = tuple5->ippair_v6->sip_net_order.s6_addr32[0]; /* ʹ�����4�ֽ� */

+			dip = tuple5->ippair_v6->dip_net_order.s6_addr32[0]; /* ʹ�����4�ֽ� */

+			sport_no_id_hash = ntohs(tuple5->sport_net_order) & FLWD_UDP_SPORT_ACTUAL_PORT_MASK;

+			dport = tuple5->dport_net_order;

+		}else{

+			sip = tuple5->ippair_v6->dip_net_order.s6_addr32[0]; /* ʹ�����4�ֽ� */

+			dip = tuple5->ippair_v6->sip_net_order.s6_addr32[0]; /* ʹ�����4�ֽ� */

+			sport_no_id_hash = ntohs(tuple5->dport_net_order) & FLWD_UDP_SPORT_ACTUAL_PORT_MASK;

+			dport = tuple5->sport_net_order;			

+		}

+	}

+

+	port_union = (unsigned int)sport_no_id_hash;

+	port_union |= ((unsigned int)dport << 16);

+	port_union += JHASH_INITVAL;	

+	

+	__jhash_final(sip, dip, port_union);

+

+	return port_union;

+}

+