信号处理配置物理网络接口配置加载配置文件的加载虚拟网络设备初始化路由向量表初始化定时器初始化
sigemptyset(&sa.sa_mask);
sigaction(SIGTERM, &sa, NULL);
sigaction(SIGINT, &sa, NULL);struct IfDesc {
char Name[ sizeof( ((struct ifreq *)NULL)->ifr_name ) ];
struct in_addr InAdr; /* == 0 for non IP interfaces */
short Flags;
short state; //状态：如upstream、downstream
struct SubnetList* allowednets; //一个子网链表
unsigned int robustness;
unsigned char threshold; /* ttl limit */
unsigned int ratelimit;
unsigned int index;
}; if ( (MRouterFD = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP)) < 0 )//打开套接口MRouterFD
log( LOG_ERR, errno, "IGMP socket open" );
if ( setsockopt( MRouterFD, IPPROTO_IP, MRT_INIT,(void *)&Va, sizeof( Va ) ) )//激活Linux内核模块mrouted服务
return errno;setsockopt( MRouterFD, IPPROTO_IP, MRT_ADD_VIF, (char *)&VifCtl, sizeof( VifCtl ) )
struct vifctl {
vifi_t vifc_vifi; /* Index of VIF */
unsigned char vifc_flags; /* VIFF_ flags */
unsigned char vifc_threshold; /* ttl limit */
unsigned int vifc_rate_limit; /* Rate limiter values (NI) */
union {
struct in_addr vifc_lcl_addr; /* Local interface address */
int vifc_lcl_ifindex; /* Local interface index */
};
struct in_addr vifc_rmt_addr; /* IPIP tunnel addr */
};struct ip
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
unsigned int ip_hl:4; /* header length */
unsigned int ip_v:4; /* version */
#endif
#if __BYTE_ORDER == __BIG_ENDIAN
unsigned int ip_v:4; /* version */
unsigned int ip_hl:4; /* header length */
#endif
u_int8_t ip_tos; /* type of service */
u_short ip_len; /* total length */
u_short ip_id; /* identification */
u_short ip_off; /* fragment offset field */
#define IP_RF 0x8000 /* reserved fragment flag */
#define IP_DF 0x4000 /* dont fragment flag */
#define IP_MF 0x2000 /* more fragments flag */
#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
u_int8_t ip_ttl; /* time to live */
u_int8_t ip_p; /* protocol */
u_short ip_sum; /* checksum */
struct in_addr ip_src, ip_dst; /* source and dest address */
};allhosts_group = htonl(INADDR_ALLHOSTS_GROUP); //224.0.0.1 在本子网上的所有参加多播的主机和路由器 allrouters_group = htonl(INADDR_ALLRTRS_GROUP); //224.0.0.2 在本子网上的所有参加多播的路由器
joinMcGroup( getMcGroupSock(), Dp, allrouters_group );
joinleave( int Cmd, int UdpSock, struct IfDesc *IfDp, uint32 mcastaddr )
setsockopt( UdpSock, IPPROTO_IP,
Cmd == 'j' ? IP_ADD_MEMBERSHIP : IP_DROP_MEMBERSHIP,
(void *)&CtlReq, sizeof( CtlReq ) )void callout_init() {
queue = NULL;
}igmpproxy源代码学习——igmpProxyInit()
原文地址：http://blog.csdn.net/windeal3203/article/details/39339761
