IGMP协议

IGMP协议

转：http://opengrok.creo.hu/dragonfly/xref/src/sys/netinet/igmp.h
           /*
     61 * IGMP packet format.
     62 */
     63 struct igmp {
     64 u_char igmp_type; /* version & type of IGMP message */
     65 u_char igmp_code; /* subtype for routing msgs */
     66 u_short igmp_cksum; /* IP-style checksum */
     67 struct in_addr igmp_group; /* group address being reported */
     68 }; /*  (zero for queries) */
     69
     70 # define IGMP_MINLEN      8
     71
     72 /*
     73 * Message types, including version number.
     74 */
     75 # define IGMP_MEMBERSHIP_QUERY 0x11 /* membership query */
     76 # define IGMP_V1_MEMBERSHIP_REPORT 0x12 /* Ver. 1 membership report */
     77 # define IGMP_V2_MEMBERSHIP_REPORT 0x16 /* Ver. 2 membership report */
     78 # define IGMP_V2_LEAVE_GROUP 0x17 /* Leave-group message */
     79
     80 # define IGMP_DVMRP 0x13 /* DVMRP routing message */
     81 # define IGMP_PIM 0x14 /* PIM routing message */
     82
     83 # define IGMP_MTRACE_RESP 0x1e  /* traceroute resp.(to sender)*/
     84 # define IGMP_MTRACE 0x1f  /* mcast traceroute messages */
     85
     86 # define IGMP_MAX_HOST_REPORT_DELAY   10    /* max delay for response to
     87     *  query (in seconds) according
     88     *  to RFC1112 */
     89
     90 # define IGMP_TIMER_SCALE     10 /* denotes that the igmp code field
     91 * specifies time in 10th of seconds*/
     92
     93 /*
     94 * The following four defininitions are for backwards compatibility.
     95 * They should be removed as soon as all applications are updated to
     96 * use the new constant names.
     97 */
     98 # define IGMP_HOST_MEMBERSHIP_QUERY IGMP_MEMBERSHIP_QUERY
     99 # define IGMP_HOST_MEMBERSHIP_REPORT IGMP_V1_MEMBERSHIP_REPORT
    100 # define IGMP_HOST_NEW_MEMBERSHIP_REPORT IGMP_V2_MEMBERSHIP_REPORT
    101 # define IGMP_HOST_LEAVE_MESSAGE IGMP_V2_LEAVE_GROUP