igmp_polltest.c

linux_unix下igmp协议代码/在redhat/arm7下均可以使用

#include <stdlib.h> 
#include <stdio.h> 

#include <sys/types.h> 
#include <sys/socket.h> 

#include <netinet/in.h> 
#include <arpa/inet.h> 

#include <netinet/in_systm.h> 
#include <netinet/ip.h> 
#include <netinet/igmp.h> 

#include <strings.h> 
#include <unistd.h> 

#define IPVERSION 4 

#define BUFFSIZE (sizeof(struct igmp) + sizeof(struct iphdr)) 

unsigned short in_cksum(unsigned short *addr,int len) 
{ 
        register int sum = 0; 
        u_short answer = 0; 
        register u_short *w = addr; 
        register int nleft = len; 

        /* 
         * Our algorithm is simple, using a 32 bit accumulator (sum), we add 
         * sequential 16 bit words to it, and at the end, fold back all the 
         * carry bits from the top 16 bits into the lower 16 bits. 
         */ 
        while (nleft > 1)  { 
                sum += *w++; 
                nleft -= 2; 
        } 

        /* mop up an odd byte, if necessary */ 
        if (nleft == 1) { 
                *(u_char *)(&answer) = *(u_char *)w ; 
                sum += answer; 
        } 

        /* add back carry outs from top 16 bits to low 16 bits */ 
        sum = (sum >> 16) + (sum & 0xffff);     /* add hi 16 to low 16 */ 
        sum += (sum >> 16);                     /* add carry */ 
        answer = ~sum;                          /* truncate to 16 bits */ 
        return(answer); 
} 



int Send_IGMP_messege(char *addr,short type) 
{ 
  	struct igmp *igmphdr; 
  	struct iphdr *iphdr; 
	int sockd; 
	int dummy,on;
	int tmp;
 	struct sockaddr_in mysocket; 
  	unsigned char buff[BUFFSIZE]; 
  	if((sockd = socket(AF_INET,SOCK_RAW,IPPROTO_RAW)) < 0)  { 
    		perror("socket"); 
   		return -1; 
	} 

	  iphdr = (struct iphdr *)buff; 
	  bzero((char *)iphdr,sizeof(struct iphdr)); 
	  
	  iphdr->ihl = 5; 
	  iphdr->version = IPVERSION; 
	    
	  iphdr->tot_len = htons(sizeof(struct iphdr) + sizeof(struct igmp)); 
	  
	  iphdr->id = htons(getpid()); 
	  iphdr->ttl = 1; 
	  iphdr->protocol = 2; 

	  iphdr->saddr = inet_addr("192.168.2.138"); /*本地地址*/

	  if(type == 0x11)
	  	iphdr->daddr = inet_addr("224.0.0.1");
	  else
	  	iphdr->daddr = inet_addr(addr); 
	  iphdr->check = in_cksum((unsigned short *)iphdr,sizeof(struct iphdr)); 
	  
	  igmphdr = (struct igmp*)(buff +sizeof(struct iphdr)); 
	  bzero((char *)igmphdr,sizeof(struct igmp)); 
	  
	  igmphdr->igmp_type = type; 
	  igmphdr->igmp_code = 0; 	

	  if(type == 0x11)
	  	inet_pton(AF_INET,"0.0.0.0",&igmphdr->igmp_group);
	  else
	  	inet_pton(AF_INET,addr,&igmphdr->igmp_group);

	  igmphdr->igmp_cksum = in_cksum((unsigned short *)igmphdr, sizeof(struct igmp)); 
	  
	  bzero((char *)&mysocket,sizeof(mysocket)); 
	  
	  mysocket.sin_family = AF_INET; 
	  if(type == 0x11)
	  	mysocket.sin_addr.s_addr = inet_addr("224.0.0.1");
	  else
	  	mysocket.sin_addr.s_addr = inet_addr(addr); 
	  if((tmp = sendto(sockd,(char *)buff,sizeof(buff),0x0, 
	       (struct sockaddr *)&mysocket,sizeof(mysocket))) < 0)  { 
	    	perror("sendto"); 
	    	return -1; 
	  } 
	  printf("tmp : %d \n",tmp);
	  close(sockd);
	  return 0; 
}
/**************************************************/
/*	参数:希望加入的IPV4 组播组地址
/*	返回:正确返回0
/*		     网络错误返回-1
/**************************************************/
int Send_IGMP_Join(char * addr)
{
	return Send_IGMP_messege(addr,0x16);	
}
/***************************************************/
/*	参数:希望退出的IPv4组播组地址
/*	返回:正确返回0
/*		     错误返回-1
/***************************************************/
int Send_IGMP_Leave(char * addr)
{
	return Send_IGMP_messege(addr,0x17);
}
int Send_IGMP_Poll(char * addr)
{
	return Send_IGMP_messege(addr,0x11);
}
/***************************************************/
/*	监听轮询信息，并作出应答。
/*	参数:监听来自哪个组播地址的轮询
/***************************************************/
void IGMP_Listen(char * addr)
{
	struct igmp *igmphdr; 
  	struct iphdr *iphdr;
	int sockd,nready; 
	fd_set rset,allset;
	char buf[64];
	if((sockd = socket(AF_INET,SOCK_RAW,IPPROTO_RAW)) < 0)  { 
    		perror("socket"); 
   		return ; 
	} 
	while(1)
	{
		FD_ZERO(&allset);
		FD_SET(sockd,&allset);
		nready=select(sockd+1,&rset,NULL,NULL,NULL);
		if(FD_ISSET(sockd,&rset))
		{
			if(recvfrom(sockd,buf,sizeof(buf),0,NULL,NULL) < 0){
				perror("sendto"); 
	    			return ; 
			}

		}
		usleep(10);
	}	
}



int main()
{
	//Send_IGMP_Join("224.0.0.4");
	//Send_IGMP_Leave("224.0.0.4");
	Send_IGMP_Poll("224.0.0.4");
	return 0;
}