声明：由于CMX micronet的协议栈是需要付费的，此代码来源于网上，用来学习交流，用于其它的商业活动请联系
最近在弄毕业设计，拿的是同事做好的一个51的串口转网口的板子，cpu c8051f340 ，比较高档的一个51单片机,silicon lab公司的，改进的cip-51内核，所有的外设配置都比较灵活，感觉不错。网卡也是 silicon labs cp2200,官方有两者应用的公板出售，并且提供协议栈，但是对协议栈封装成了库，看不到原代码，比较不爽，同事给我的代码用的不是库了，而是实实在在的代码，后来网上一查，这个协议栈是基于cmx micronet改过来的，此前对网络的这些底层实现基本为0,研究了几天，看明白了点点。
目前的代友码主要实现了arp icmp ip tcp udp http,目前是一个webserver,通过html提交数据向串口发出数据。
主要的程序目录如下：
c8051f340.h------此单片机的一些sfr及地址的定义
cp220x.h---------cp220x的寄存器定义
cp220x.c---------将cp220x的寄存器映射到51的地址空间
net.h------------定义了一些各种协议的报文头格式及一些标志位，还有些预处理
arp.h------------arp协议的实现的所需函数的声明
arp.c------------arp协议实现所需函数的具体实现
icmp.h-----------icmp协议的实现的所需函数的声明
icmp.c-----------icmp协议实现所需函数的具体实现
tcp.h------------tcp协议的实现的所需函数的声明
tcp.c------------tcp协议实现所需函数的具体实现
udp.h------------udp协议的实现的所需函数的声明
udp.c------------udp协议实现所需函数的具体实现
http.h-----------http协议的实现的所需函数的声明
http.c-----------http协议实现所需函数的具体实现
cksum.h----------校验和所需函数的声明
cksum.c----------校验和所需函数的实现
先看net.h文件
注：我只是加了些中文注释
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//-----------------------------------------------------------------------------
// NET.H
//一些网络相关的包，报文头，常量的数据结构
//-----------------------------------------------------------------------------
typedef unsigned char UCHAR;//1 byte
typedef unsigned int UINT;//2 bytes
typedef unsigned long ULONG;//4 bytes
typedef unsigned long LONG;
void eth_send(UCHAR xdata * outbuf, UCHAR * hwaddr, UINT ptype, UINT len);
// 常量定义
#define TRUE 1
#define ON 1
#define OK 1
#define FALSE 0
#define OFF 0
#define MATCH 0
#define RET 0x0D
#define LF 0x0A
#define SPACE 0x20
// 端口定义
#define ECHO_PORT 7
#define DAYTIME_PORT 13
#define CHARGEN_PORT 19
#define TIME_PORT 37
#define HTTP_PORT 80
// 事件标志
#define EVENT_ETH_ARRIVED 0x0001 //有待处理的以太网帧事件
#define EVENT_AGE_ARP_CACHE 0x0002 //更新ARP缓存事件 60s更新一次
#define EVENT_TCP_RETRANSMIT 0x0004 //TCP重传事件
#define EVENT_TCP_INACTIVITY 0x0008 //关断不活动连接事件 (0.5s)
#define EVENT_ARP_RETRANSMIT 0x0010 //ARP请求数据包重传事件
#define EVENT_READ_ANALOG 0x0020
#define EVENT_RS232_ARRIVED 0x0040 //串口数据到达事件
// 以太网络帧的类型
#define IP_PACKET 0x0800
#define ARP_PACKET 0x0806
#define RARP_PACKET 0x8035
// IP数据段中所采用的协议类型
#define ICMP_TYPE 1
#define IGMP_TYPE 2
#define TCP_TYPE 6
#define UDP_TYPE 17
//ARP消息类型
#define ARP_REQUEST 1
#define ARP_RESPONSE 2
#define RARP_REQUEST 3
#define RARP_RESPONSE 4
// 在ARP报文中的硬件类型
#define DIX_ETHERNET 1
#define IEEE_ETHERNET 6
//ARP缓存
typedef struct
{
ULONG ipaddr;
UCHAR hwaddr[6];
UCHAR timer;
} ARP_CACHE;
//ARP请求后的答复
typedef struct
{
UCHAR xdata * buf;
ULONG ipaddr;
UCHAR proto_id;
UINT len;
UCHAR timer;
} WAIT;
//ARP报文头 28字节
typedef struct
{
UINT hardware_type;//硬件类型2byte
UINT protocol_type;//协议类型2byte
UCHAR hwaddr_len;//MAC地址长度1byte
UCHAR ipaddr_len;//IP地址长度1byte
UINT message_type;//操作类型 arp应答、arp请求、rarp应答、rarp请求
UCHAR source_hwaddr[6];//源MAC地址
ULONG source_ipaddr;//源IP地址
UCHAR dest_hwaddr[6];//目的MAC地址
ULONG dest_ipaddr;//目的IP地址
} ARP_HEADER;
//以太网帧头部 14字节
typedef struct
{
UCHAR dest_hwaddr[6]; //目的mac地址
UCHAR source_hwaddr[6]; //源mac地址
UINT frame_type; //协议类型
} ETH_HEADER;
//IP报文头 20字节
typedef struct
{
UCHAR ver_len; //版本(4bit)与此报文头的长度(4bit)
UCHAR type_of_service; //服务类型 8bit,用数值表示出报文的重要程度，此数大的报文优先
UINT total_length; //总长度 16bit
UINT identifier; //标识 16bit(假如多于一个报文，用来标识出报文位置)
UINT fragment_info; //标志(3bit)片偏移(13bit)
UCHAR time_to_live; //生存时间(8bit)
UCHAR protocol_id; //处理此报文的上层协议(8bit)
UINT header_cksum; //首部检验和(16bit)
ULONG source_ipaddr; //源IP(32bit)
ULONG dest_ipaddr; // 目的IP(32bit)
} IP_HEADER;
//ICMP PING回显请求报文结构
typedef struct
{
UCHAR msg_type;//类型8bit
UCHAR msg_code;//代码 8bit
UINT checksum;//校验和16bit
UINT identifier;//标识符16bit
UINT sequence;//序号16bit
UCHAR echo_data;//选项数据，必须回显
} PING_HEADER;
//ICMP差错报文结构(目的不可达报文)
typedef struct
{
UCHAR msg_type; //类型8bit
UCHAR msg_code; //代码 8bit
UINT checksum; //校验和16bit
ULONG msg_data; //消息数据32bit
UCHAR echo_data; //回显数据8bit
} ICMP_ERR_HEADER;
//UDP数据包结构
typedef struct
{
UINT source_port;
UINT dest_port;
UINT length;
UINT checksum;
UCHAR msg_data;
} UDP_HEADER;
//TCP报文头 21字节(不算选项的话21字节)
typedef struct
{
UINT source_port;//源端口号 16bit
UINT dest_port; //目的端口号 16bit
ULONG sequence; //序号从TCP发端向TCP收端发送的数据字节流 32bit
ULONG ack_number; //32bit 确认序号
UINT flags; //首部长度及一些标志位
UINT window; //窗口大小 16bit
UINT checksum;//校验和 16bit
UINT urgent_ptr;//紧急指针16bit
UCHAR options;//选项
} TCP_HEADER;
//TCP连接的数据结构
typedef struct
{
ULONG ipaddr;
UINT port;
ULONG his_sequence;
ULONG my_sequence;
ULONG old_sequence;
ULONG his_ack;
UCHAR timer;
UCHAR inactivity;
UCHAR state;
char query[20];
} CONNECTION;
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再看一下arp协议所实现 的函数
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//-----------------------------------------------------------------------------
//模块处理ARP消息和APR应求并且管理ARP缓存(ARP协议实现)
//-----------------------------------------------------------------------------
#include <string.h>
#include <stdio.h>
#include "C8051f340.h"
#include "net.h"
#include "ip.h"
#include "arp.h"
extern WAIT xdata wait;
extern UCHAR xdata my_hwaddr[];
extern UCHAR code broadcast_hwaddr[];
extern ULONG code my_ipaddr;
extern ULONG code my_subnet;
extern ULONG code gateway_ipaddr;
extern UCHAR idata debug;
ARP_CACHE xdata arp_cache[CACHESIZE];// 定义arp缓存为10个ARP_CACHE单位
UCHAR waiting_for_arp;
extern char xdata outbuf1[];
void init_arp(void)
{
memset(arp_cache, 0, sizeof(arp_cache)); //初始化arp缓存全部为0
memset(&wait, 0, sizeof(wait)); //初台化wait空间
waiting_for_arp = FALSE; //无arp请求
}
//------------------------------------------------------------------------
// This is called every 60 seconds to age the ARP cache
// If an entry times out then it is deleted from the cache
// See "TCP/IP Illustrated, Volume 1" Sect 4.3
// 函数作用：更新ARP缓存
//------------------------------------------------------------------------
void age_arp_cache(void)
{
UCHAR i;
for (i=0; i < CACHESIZE; i++)//查询arp缓存表
{
if ((arp_cache[i].ipaddr != 0) && (arp_cache[i].timer))
{
arp_cache[i].timer--;
if (arp_cache[i].timer == 0)
{
// Timed out so clear out cache entry
// Do not need to zero hwaddr
//时间到则进行清零
arp_cache[i].ipaddr = 0;
}
}
}
}
//------------------------------------------------------------------------
// This allocates memory for the entire outgoing message,
// including eth and ip headers, then builds an outgoing
// ARP response message
// See "TCP/IP Illustrated, Volume 1" Sect 4.4
// ARP请求广播
//------------------------------------------------------------------------
void arp_send(UCHAR * hwaddr, ULONG ipaddr, UCHAR msg_type)
{
UCHAR xdata * outbuf;
ARP_HEADER xdata * arp;
// Allocate memory for entire outgoing message including
// eth header. Always 42 bytes
// outbuf = (UCHAR xdata *)malloc(42);
outbuf = outbuf1;
// Allow 14 bytes for the ethernet header//前14个字节为以太网帧头部
arp = (ARP_HEADER xdata *)(outbuf + 14);
arp->hardware_type = DIX_ETHERNET;
arp->protocol_type = IP_PACKET;
arp->hwaddr_len = 6;
arp->ipaddr_len = 4;
arp->message_type = (UINT)msg_type;
// My hardware address and IP addresses
memcpy(arp->source_hwaddr, my_hwaddr, 6);
arp->source_ipaddr = my_ipaddr;
// Destination hwaddr and dest IP addr
if (msg_type == ARP_REQUEST) memset(arp->dest_hwaddr, 0, 6);
else memcpy(arp->dest_hwaddr, hwaddr, 6);
arp->dest_ipaddr = ipaddr;
// If request then the message is a brodcast, if a response then
// send to specified hwaddr
// ARP payload size is always 28 bytes
if (msg_type == ARP_REQUEST) eth_send(outbuf, broadcast_hwaddr, ARP_PACKET, 28);
else eth_send(outbuf, hwaddr, ARP_PACKET, 28);
}
//------------------------------------------------------------------------
// This re-sends an ARP request if there was no response to
// the first one. It is called every 0.5 seconds. If there
// is no response after 2 re-tries, the datagram that IP was
// trying to send is deleted
//ARP重新发送
//-----------------------------------------------------------------------
void arp_retransmit(void)
{
static UCHAR idata retries = 0;
if ((waiting_for_arp) && (wait.timer))
{
wait.timer--;
if (wait.timer == 0)
{
retries++;
if (retries <= 2)
{
arp_send(NULL, wait.ipaddr, ARP_REQUEST);
wait.timer = ARP_TIMEOUT;
}
else
{
wait.timer = 0;
waiting_for_arp = 0;
// free(wait.buf);
}
}
}
}
//------------------------------------------------------------------------
// Find the ethernet hardware address for the given ip address
// If destination IP is on my subnet then we want the eth
// address of destination, otherwise we want eth addr of gateway.
// Look in ARP cache first. If not found there, send ARP request.
// Return pointer to the hardware address or NULL if not found
// See "TCP/IP Illustrated, Volume 1" Sect 4.5
//ARP将IP地址解析为硬件地址的过程，返回mac 地址存储的首地址
//------------------------------------------------------------------------
UCHAR xdata * arp_resolve(ULONG dest_ipaddr)
{
UCHAR i;
// If destination IP is not on my subnet then we really want eth addr
// of gateway, not destination IP
if ((dest_ipaddr ^ my_ipaddr) & my_subnet)
{
if (gateway_ipaddr == 0)
{
return (NULL);
}
else dest_ipaddr = gateway_ipaddr;
}
// See if IP addr of interest is in ARP cache
for (i=0; i < CACHESIZE; i++)
{
if (arp_cache[i].ipaddr == dest_ipaddr)
return (&arp_cache[i].hwaddr[0]);
}
// Not in cache so broadcast ARP request
arp_send(NULL, dest_ipaddr, ARP_REQUEST);
// Set a flag to indicate that an IP datagram is waiting
// to be sent
waiting_for_arp = TRUE;
// Null means that we have sent an ARP request
return (NULL);
}
//------------------------------------------------------------------------
// This handles incoming ARP messages
// See "TCP/IP Illustrated, Volume 1" Sect 4.4
// Todo: Resolve problem of trying to add to a full cache
// 接收ARP回复
//------------------------------------------------------------------------
void arp_rcve(UCHAR xdata * inbuf)
{
UCHAR idata i, cached, oldest;
UINT idata minimum;
ARP_HEADER xdata * arp;
arp = (ARP_HEADER xdata *)(inbuf + 14); //去除以太网帧的头信息
cached = FALSE;
// Print message
// Validate incoming frame //表明是无效的帧
if ((arp->hardware_type != DIX_ETHERNET) ||
(arp->protocol_type != IP_PACKET)) return;
// Search ARP cache for senders IP address
// If found, update entry and restart timer
for (i=0; i < CACHESIZE; i++)
{
if (arp_cache[i].ipaddr == arp->source_ipaddr)
{
memcpy(&arp_cache[i].hwaddr[0], &arp->source_hwaddr[0], 6);
arp_cache[i].timer = CACHETIME;
cached = TRUE;
break;
}
}
if (arp->dest_ipaddr != my_ipaddr) return;
// At this point we know the the frame is addressed to me
// If not already in cache then add entry and start timer
if (cached == FALSE)
{
// Find first blank space and add entry
// Blank entries are indicated by ip addr = 0
for (i=0; i < CACHESIZE; i++)
{
if (arp_cache[i].ipaddr == 0)
{
arp_cache[i].ipaddr = arp->source_ipaddr;
memcpy(&arp_cache[i].hwaddr[0], &arp->source_hwaddr[0], 6);
arp_cache[i].timer = CACHETIME;
break;
}
}
// If no blank entries in arp cache then sort cache
// to find oldest entry and replace it
if (i == CACHESIZE)
{
// Oldest entry is the one with lowest timer value
minimum = 0xFFFF;
for (i=0; i < CACHESIZE; i++)
{
if (arp_cache[i].timer < minimum)
{
minimum = arp_cache[i].timer;
oldest = i;
}
}
// "oldest" is now index of oldest entry, so replace it
arp_cache[oldest].ipaddr = arp->source_ipaddr;
memcpy(&arp_cache[oldest].hwaddr[0], &arp->source_hwaddr[0], 6);
arp_cache[oldest].timer = CACHETIME;
}
}
// If we are waiting for an arp response and the arp response
// that just came in is addressed to me and is from the host
// we are waiting for, then send the message-in-waiting
if (arp->message_type == ARP_RESPONSE)
{
if ((waiting_for_arp) && (wait.ipaddr == arp->source_ipaddr))
{
waiting_for_arp = FALSE;
ip_send(wait.buf, wait.ipaddr, wait.proto_id, wait.len);
}
}
else if (arp->message_type == ARP_REQUEST)
{
// Send ARP response
arp_send(arp->source_hwaddr, arp->source_ipaddr, ARP_RESPONSE);
}
}
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//-----------------------------------------------------------------------------
// ARP.H
//每条ARP缓存记录的生命周期为20分钟，2分钟内未用则删除。
//缓存容量满时，删除最老的记录
//-----------------------------------------------------------------------------
// Allow up to 10 entries in ARP cache
#define CACHESIZE 10 //ARP缓存大小
// ARP cache entry expiration time = 20 minutes
#define CACHETIME 20 // 60 second intervals
// Allow 2 seconds to receive an ARP reply
#define ARP_TIMEOUT 4 // 0.5 second intervals
void init_arp(void);
UCHAR xdata * arp_resolve(ULONG);
void arp_rcve(UCHAR xdata *);
void age_arp_cache(void);
void arp_retransmit(void);
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程序注释得比较清晰了，具体过程需要参考tcp/ip 详解
再就是ip协议了，这个虽然经过精简后只有两个函数，看起来还是很抽像的
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//-----------------------------------------------------------------------------
// 实现IP协议
// 参考 RFC 791, 1122, RFC 815
//-----------------------------------------------------------------------------
#include <string.h>
#include "C8051f340.h"
#include "net.h"
#include "cksum.h"
#include "arp.h"
#include "icmp.h"
#include "tcp.h"
#include "ip.h"
extern UCHAR idata debug;
extern ULONG code my_ipaddr;
WAIT xdata wait;
//------------------------------------------------------------------------
// This handles outgoing IP datagrams. It adds the 20 byte IP header
// and checksum then forwards the IP datagram to the Ethernet layer
// for sending. See "TCP/IP Illustrated, Volume 1" Sect 3.2
// 处理向外发送的IP报文
//------------------------------------------------------------------------
void ip_send(UCHAR xdata * outbuf, ULONG ipaddr, UCHAR proto_id, UINT len)
{
IP_HEADER xdata * ip;
UCHAR xdata * hwaddr;
static UINT ip_ident = 0;
ip = (IP_HEADER xdata *)(outbuf + 14); //14byte是以太网帧的报文头
ip->ver_len = 0x45; // IPv4 with 20 byte header
ip->type_of_service = 0;
ip->total_length = 20 + len;
ip->identifier = ip_ident++; // sequential identifier
ip->fragment_info = 0; // not fragmented 不分段
ip->time_to_live = 32; // max hops
ip->protocol_id = proto_id; // type of payload
ip->header_cksum = 0;
ip->source_ipaddr = my_ipaddr;
// Outgoing IP address
ip->dest_ipaddr = ipaddr;
// Compute and insert complement of checksum of ip header
// Outgoing ip header length is always 20 bytes
ip->header_cksum = ~cksum(outbuf + 14, 20);
// Use ARP to get hardware address to send this to
hwaddr = arp_resolve(ip->dest_ipaddr);
// Null means that the ARP resolver did not find the IP address
// in its cache so had to send an ARP request
if (hwaddr == NULL)
{
// Fill in the destination information so ehrn the ARP response
// arrives we can identify it and know what to do when we get it
wait.buf = outbuf;
wait.ipaddr = ip->dest_ipaddr;
wait.proto_id = proto_id;
wait.len = len;
wait.timer = ARP_TIMEOUT;
return;
}
eth_send(outbuf, hwaddr, IP_PACKET, 20 + len);
}
//------------------------------------------------------------------------
// This handles incoming IP datagrams from the Ethernet layer
// See "TCP/IP Illustrated, Volume 1" Sect 3.2
//------------------------------------------------------------------------
void ip_rcve(UCHAR xdata * inbuf)
{
IP_HEADER xdata * ip;
UINT idata header_len, payload_len;
ip = (IP_HEADER xdata *)(inbuf + 14);
// Make sure it is addressed to my IP address
if (ip->dest_ipaddr != my_ipaddr) return;
// Validate checksum of ip header
header_len = 4 * (0x0F & ip->ver_len);
payload_len = ip->total_length - header_len;
if (cksum(inbuf + 14, header_len) != 0xFFFF)
{
return;
}
// Make sure incoming message is IP version 4
if ((ip->ver_len >> 4) != 0x04)
{
return;
}
// Make sure incoming message is not fragmented because
// we cannot handle fragmented messages
//确保收进来的IP报文头是没有分段的，分段报文无法处理
if ((ip->fragment_info & 0x3FFF) != 0)
{
return;
}
// At this point we have received a valid IP datagram addressed
// to me. We do not use header options, and do not forward
// messages, so in the unlikely event there are header options,
// delete them and shift the data down. The advantage is that
// layers such as UDP and TCP know where their data starts
// 如果报文头大于20的话，则需进行处理
if (header_len > 20)
{
// Use memmove because of overlap
memmove(inbuf + 34, inbuf + 14 + header_len, payload_len);
// Adjust info to reflect the move
header_len = 20;
ip->ver_len = 0x45;
ip->total_length = 20 + payload_len;
}
// Look at protocol ID byte and call the appropriate
// function to handle the received message. See
// "TCP/IP Illustrated, Volume 1" Sect 1.7 and RFC 791
// for values for various protocols
switch (ip->protocol_id)
{
case ICMP_TYPE:
icmp_rcve(inbuf, payload_len);
break;
case IGMP_TYPE:
;
// We cannot handle IGMP messages
break;
case UDP_TYPE:
;
break;
case TCP_TYPE:
tcp_rcve(inbuf, payload_len);
break;
default:
;
break;
}
}
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这个我也只是大致看明白了,其中有几个函数调用是网卡的驱动函数，应该能看出来。
再就是icmp协议了，这个同样对其精简了许多了，只处理了二种报文,这个代码我注释得比较详细，
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//-----------------------------------------------------------------------------
// 处理ICMP消息（ICMP协议的实现）
// 具体细节参考 RFC 792, 896, 950, 1122, 1191
//-----------------------------------------------------------------------------
#include <string.h>
#include "C8051f340.h"
#include "net.h"
#include "cksum.h"
#include "ip.h"
#include "icmp.h"
extern UCHAR idata debug;
extern char xdata outbuf1[];
//------------------------------------------------------------------------
// 建立一个ping回显应答消息，为发整个需发送的信息分配内存，包括以太帧头与IP头
// 见TCP/IP详解 卷1 7.2
//------------------------------------------------------------------------
void ping_send(UCHAR xdata * inbuf, ULONG ipaddr, UINT len)
{
PING_HEADER xdata * ping_in;
PING_HEADER xdata * ping_out;
UCHAR xdata * outbuf;
//为接受到的ping回复加上以太网帧头(14byte)与IP头(20byte)
ping_in = (PING_HEADER xdata *)(inbuf + 34);
outbuf = outbuf1;
// 为应答ping的消息加上以太网帧头(14byte)与IP头(20byte)
ping_out = (PING_HEADER xdata *)(outbuf + 34);
ping_out->msg_type = 0;
ping_out->msg_code = 0;
ping_out->checksum = 0;
ping_out->identifier = ping_in->identifier;//标识原值信息返回
ping_out->sequence = ping_in->sequence;//序号信息原值返回
//回显数据原样返回
memcpy(&ping_out->echo_data, &ping_in->echo_data, len - 8);
//校验ICMP的报文头及插入的额外的数据
ping_out->checksum = ~cksum(outbuf + 34, len);
//通过IP数据报发磅
ip_send(outbuf, ipaddr, ICMP_TYPE, len);
}
//------------------------------------------------------------------------
//目的不可达报文 类型3 代码3 表示目的不可达报文是由端口不可达
//处理方法是返回我们收到的原始的IP数据报文头，20byte以后的数据全部不收
//详见TCP/IP详解 卷1 6.5
//------------------------------------------------------------------------
void dest_unreach_send(UCHAR xdata * inbuf, ULONG ipaddr)
{
UCHAR xdata * outbuf;
ICMP_ERR_HEADER xdata * icmp;
outbuf = outbuf1;
icmp = (ICMP_ERR_HEADER xdata *)(outbuf + 34);
// 填充ICMP出错报文的头
icmp->msg_type = 3; // 目的不可达
icmp->msg_code = 3; // 端口不可达
icmp->checksum = 0;
// 填充ICMP错误信息数据
icmp->msg_data = 0;
// 拷贝20字节的原始IP地址头
// 及ICMP_ERR_HEADER的前8字节,
//echo_data数据的地址用来存放前边提到的28字节
memcpy(&icmp->echo_data, inbuf + 14, 28);
//校验36字节,ICMP_ERR_HEADER头的前8字节
//及echo_data数据的地址用来存放前边提到的28字节
icmp->checksum = ~cksum(outbuf + 34, 36);
// 通过IP数据报发送
ip_send(outbuf, ipaddr, ICMP_TYPE, 36);
}
//------------------------------------------------------------------------
// 处理收到ICMP请求
// 详见TCP/IP详解 卷1 6.2
//------------------------------------------------------------------------
void icmp_rcve(UCHAR xdata * inbuf, UINT len)
{
IP_HEADER * ip;
UCHAR idata msg_type;
UINT idata temp;
// 前边是以太网帧头的14个字节
ip = (IP_HEADER *)(inbuf + 14);
// IP 头在前边已将地址确定
// 对有效的ICMP消息数据进行校验
temp = cksum(inbuf + 34, len);
if (temp != 0xFFFF)
{
return;
}
// 通过ICMP消息类型做出相应的处理
msg_type = *(inbuf + 34);
switch(msg_type)
{
case 3:
;
break;
case 8://请求回显(ping请求)//则用ping发送回显
ping_send(inbuf, ip->source_ipaddr, len);
break;
default:
;
break;
}
}
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还有过TCP协议的实现还没有彻底研究明白，研究后与http协议一起贴出来.
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