ip.h.svn-base

来自「数字广播系统的开发源码」· SVN-BASE 代码 · 共 50 行

/*
 IP
*/
#define IP_VERSION_4 0x04
#define IP_HEAD_MIN_LEN	0x14
#define IP_INITIAL_LIFE 20

#define IP_PROTOCOL_TCP	 0x06
#define IP_PROTOCOL_ICMP 0x01
#define IP_PROTOCOL_UDP  0X02

/* caculate ip version of a packet */
#define IP_VERSION(pIPHead) (pIPHead->Ver_HeadLen>>4)

/* caculate ip head len of a packet.head len in Ver_HeadLen
is mulitple of 4 byte */
#define IP_HEAD_LEN(pIPHead) ((pIPHead->Ver_HeadLen & 0x0f)*4)

#define IP_ADDR unsigned long

struct SIPHead
{
	/* Version 4 bits, HeadLength 4 bits. typical value is 0x45 */
	unsigned char Ver_HeadLen;

	/* Precedence(priority) 3 bits, Delay, Throughput, Reliability
	, reserved 2 bits. typical value 0x00 */
	unsigned char ServeType;

	unsigned int TotalLen;				/* all size of IP packet inlcude IPHead. 16 bits */
	unsigned int FragmentID;			/* 16 bits */

	/* Reserved 1 bit, May be fragmented 1 bit, Last fragment 1 bit,
	Fragment offset 13 bits. typical 0x00 */
#define	IP_FRAGMENT_OFFSET_MASK	0x1FFF
	unsigned int FragmentFlag_Offset;

	unsigned char LifeLength;			/* ttl */
	unsigned char Protocol;				/* eg. IP_PROTOCAL_TCP*/
	unsigned int CheckSum;				/* 16 bits */
	IP_ADDR IPScr;				/* 32 bits */
	IP_ADDR IPDest;
};

unsigned int CheckSum(unsigned int xdata* buff,unsigned int size,unsigned long InSum) reentrant;
void IPInput(struct SMemHead xdata*MemHead) reentrant;
unsigned char IPOutput(struct SMemHead xdata* MemHead) reentrant;