/* * Open and initialize the igmp socket, and fill in the non-changing * IP header fields in the output packet buffer. */ void initIgmp() { struct ip *ip; recv_buf = malloc(RECV_BUF_SIZE); send_buf = malloc(RECV_BUF_SIZE); k_hdr_include(true); /* include IP header when sending */ k_set_rcvbuf(256*1024,48*1024); /* lots of input buffering */ k_set_ttl(1); /* restrict multicasts to one hop */ k_set_loop(false); /* disable multicast loopback */ ip = (struct ip *)send_buf; memset(ip, 0, sizeof(struct ip)); /* * Fields zeroed that aren't filled in later: * - IP ID (let the kernel fill it in) * - Offset (we don't send fragments) * - Checksum (let the kernel fill it in) */ ip->ip_v = IPVERSION; ip->ip_hl = (sizeof(struct ip) + 4) >> 2; /* +4 for Router Alert option */ ip->ip_tos = 0xc0; /* Internet Control */ ip->ip_ttl = MAXTTL; /* applies to unicasts only */ ip->ip_p = IPPROTO_IGMP; allhosts_group = htonl(INADDR_ALLHOSTS_GROUP); allrouters_group = htonl(INADDR_ALLRTRS_GROUP); alligmp3_group = htonl(INADDR_ALLIGMPV3_GROUP); }
/* * Open and initialize the igmp socket, and fill in the non-changing * IP header fields in the output packet buffer. */ void init_igmp(void) { struct ip *ip; recv_buf = malloc(RECV_BUF_SIZE); send_buf = malloc(RECV_BUF_SIZE); if ((igmp_socket = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP)) < 0) logit(LOG_ERR, errno, "IGMP socket"); k_hdr_include(TRUE); /* include IP header when sending */ k_set_rcvbuf(256*1024,48*1024); /* lots of input buffering */ k_set_ttl(1); /* restrict multicasts to one hop */ k_set_loop(FALSE); /* disable multicast loopback */ ip = (struct ip *)send_buf; memset(ip, 0, sizeof(struct ip)); /* * Fields zeroed that aren't filled in later: * - IP ID (let the kernel fill it in) * - Offset (we don't send fragments) * - Checksum (let the kernel fill it in) */ ip->ip_v = IPVERSION; ip->ip_hl = sizeof(struct ip) >> 2; ip->ip_tos = 0xc0; /* Internet Control */ ip->ip_ttl = MAXTTL; /* applies to unicasts only */ ip->ip_p = IPPROTO_IGMP; allhosts_group = htonl(INADDR_ALLHOSTS_GROUP); dvmrp_group = htonl(INADDR_DVMRP_GROUP); allrtrs_group = htonl(INADDR_ALLRTRS_GROUP); }
/* * Open and initialize the igmp socket, and fill in the non-changing * IP header fields in the output packet buffer. */ void init_igmp(void) { struct ip *ip; char *router_alert; igmp_recv_buf = calloc(1, RECV_BUF_SIZE); igmp_send_buf = calloc(1, SEND_BUF_SIZE); if (!igmp_recv_buf || !igmp_send_buf) logit(LOG_ERR, 0, "Ran out of memory in init_igmp()"); if ((igmp_socket = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP)) < 0) logit(LOG_ERR, errno, "Failed creating IGMP socket in init_igmp()"); k_hdr_include(igmp_socket, TRUE); /* include IP header when sending */ k_set_sndbuf(igmp_socket, SO_SEND_BUF_SIZE_MAX, SO_SEND_BUF_SIZE_MIN); /* lots of output buffering */ k_set_rcvbuf(igmp_socket, SO_RECV_BUF_SIZE_MAX, SO_RECV_BUF_SIZE_MIN); /* lots of input buffering */ k_set_ttl(igmp_socket, MINTTL); /* restrict multicasts to one hop */ k_set_loop(igmp_socket, FALSE); /* disable multicast loopback */ ip = (struct ip *)igmp_send_buf; memset(ip, 0, IP_IGMP_HEADER_LEN); ip->ip_v = IPVERSION; ip->ip_hl = IP_IGMP_HEADER_LEN >> 2; ip->ip_tos = 0xc0; /* Internet Control */ ip->ip_id = 0; /* let kernel fill in */ ip->ip_off = 0; ip->ip_ttl = MAXTTL; /* applies to unicasts only */ ip->ip_p = IPPROTO_IGMP; ip->ip_sum = 0; /* let kernel fill in */ /* Enable RFC2113 IP Router Alert. Per spec this is required to * force certain routers/switches to inspect this frame. */ router_alert = igmp_send_buf + sizeof(struct ip); router_alert[0] = IPOPT_RA; router_alert[1] = 4; router_alert[2] = 0; router_alert[3] = 0; /* Everywhere in the daemon we use network-byte-order */ allhosts_group = htonl(INADDR_ALLHOSTS_GROUP); allrouters_group = htonl(INADDR_ALLRTRS_GROUP); allreports_group = htonl(INADDR_ALLRPTS_GROUP); if (register_input_handler(igmp_socket, igmp_read) < 0) logit(LOG_ERR, 0, "Failed registering igmp_read() as an input handler in init_igmp()"); }
void init_pim() {//初始化 allpimrouters=htonl(INADDR_ALLPIM_ROUTERS_GROUP); pim_receive_buf=malloc(64*1024); pim_send_buf=malloc(64*1024); if((pimsocket=socket(AF_INET,SOCK_RAW,IPPROTO_PIM))<0) log(LOG_ERR,"igmp socket create failed!"); k_hdr_include(pimsocket,1);//发送的时候包括IP头部 k_set_rcvbuf(pimsocket,256*1024,48*1024); k_set_ttl(pimsocket,1);//设置IGMP报文的TTL为1 k_set_loop(pimsocket,0);//决定发送的多点广播包不应该被回送 if(register_input_handler(pimsocket,pim_input)<0) log(LOG_ERR,"Couldn't register pim_input as an input handler"); }
/* * Setup raw kernel socket for PIM protocol and send/receive buffers. */ void init_pim(void) { struct ip *ip; /* Setup the PIM raw socket */ if ((pim_socket = socket(AF_INET, SOCK_RAW, IPPROTO_PIM)) < 0) logit(LOG_ERR, errno, "Failed creating PIM socket"); k_hdr_include(pim_socket, TRUE); /* include IP header when sending */ k_set_sndbuf(pim_socket, SO_SEND_BUF_SIZE_MAX, SO_SEND_BUF_SIZE_MIN); /* lots of output buffering */ k_set_rcvbuf(pim_socket, SO_RECV_BUF_SIZE_MAX, SO_RECV_BUF_SIZE_MIN); /* lots of input buffering */ k_set_ttl(pim_socket, MINTTL); /* restrict multicasts to one hop */ k_set_loop(pim_socket, FALSE); /* disable multicast loopback */ allpimrouters_group = htonl(INADDR_ALL_PIM_ROUTERS); pim_recv_buf = calloc(1, RECV_BUF_SIZE); pim_send_buf = calloc(1, SEND_BUF_SIZE); if (!pim_recv_buf || !pim_send_buf) logit(LOG_ERR, 0, "Ran out of memory in init_pim()"); /* One time setup in the buffers */ ip = (struct ip *)pim_send_buf; memset(ip, 0, sizeof(*ip)); ip->ip_v = IPVERSION; ip->ip_hl = (sizeof(struct ip) >> 2); ip->ip_tos = 0; /* TODO: setup?? */ ip->ip_id = 0; /* Make sure to update ID field, maybe fragmenting below */ ip->ip_off = 0; ip->ip_p = IPPROTO_PIM; ip->ip_sum = 0; /* let kernel fill in */ if (register_input_handler(pim_socket, pim_read) < 0) logit(LOG_ERR, 0, "Failed registering pim_read() as an input handler"); /* Initialize the building Join/Prune messages working area */ build_jp_message_pool = (build_jp_message_t *)NULL; build_jp_message_pool_counter = 0; }
/* * Traceroute function which returns traceroute replies to the requesting * router. Also forwards the request to downstream routers. */ void accept_mtrace(u_int32 src, u_int32 dst, u_int32 group, char *data, u_int no, int datalen) { u_char type; mrtentry_t *mrt; struct tr_query *qry; struct tr_resp *resp; int vifi; char *p; u_int rcount; int errcode = TR_NO_ERR; int resptype; struct timeval tp; struct sioc_vif_req v_req; #if 0 /* TODO */ struct sioc_sg_req sg_req; #endif /* 0 */ u_int32 parent_address = INADDR_ANY; /* Remember qid across invocations */ static u_int32 oqid = 0; /* timestamp the request/response */ gettimeofday(&tp, 0); /* * Check if it is a query or a response */ if (datalen == QLEN) { type = QUERY; IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Initial traceroute query rcvd from %s to %s", inet_fmt(src, s1, sizeof(s1)), inet_fmt(dst, s2, sizeof(s2))); } else if ((datalen - QLEN) % RLEN == 0) { type = RESP; IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "In-transit traceroute query rcvd from %s to %s", inet_fmt(src, s1, sizeof(s1)), inet_fmt(dst, s2, sizeof(s2))); if (IN_MULTICAST(ntohl(dst))) { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Dropping multicast response"); return; } } else { logit(LOG_WARNING, 0, "%s from %s to %s", "Non decipherable traceroute request recieved", inet_fmt(src, s1, sizeof(s1)), inet_fmt(dst, s2, sizeof(s2))); return; } qry = (struct tr_query *)data; /* * if it is a packet with all reports filled, drop it */ if ((rcount = (datalen - QLEN)/RLEN) == no) { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "packet with all reports filled in"); return; } IF_DEBUG(DEBUG_TRACE) { logit(LOG_DEBUG, 0, "s: %s g: %s d: %s ", inet_fmt(qry->tr_src, s1, sizeof(s1)), inet_fmt(group, s2, sizeof(s2)), inet_fmt(qry->tr_dst, s3, sizeof(s3))); logit(LOG_DEBUG, 0, "rttl: %d rd: %s", qry->tr_rttl, inet_fmt(qry->tr_raddr, s1, sizeof(s1))); logit(LOG_DEBUG, 0, "rcount:%d, qid:%06x", rcount, qry->tr_qid); } /* determine the routing table entry for this traceroute */ mrt = find_route(qry->tr_src, group, MRTF_SG | MRTF_WC | MRTF_PMBR, DONT_CREATE); IF_DEBUG(DEBUG_TRACE) { if (mrt != (mrtentry_t *)NULL) { if (mrt->upstream != (pim_nbr_entry_t *)NULL) parent_address = mrt->upstream->address; else parent_address = INADDR_ANY; logit(LOG_DEBUG, 0, "mrt parent vif: %d rtr: %s metric: %d", mrt->incoming, inet_fmt(parent_address, s1, sizeof(s1)), mrt->metric); /* TODO logit(LOG_DEBUG, 0, "mrt origin %s", RT_FMT(rt, s1)); */ } else { logit(LOG_DEBUG, 0, "...no route"); } } /* * Query type packet - check if rte exists * Check if the query destination is a vif connected to me. * and if so, whether I should start response back */ if (type == QUERY) { if (oqid == qry->tr_qid) { /* * If the multicast router is a member of the group being * queried, and the query is multicasted, then the router can * recieve multiple copies of the same query. If we have already * replied to this traceroute, just ignore it this time. * * This is not a total solution, but since if this fails you * only get N copies, N <= the number of interfaces on the router, * it is not fatal. */ IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "ignoring duplicate traceroute packet"); return; } if (mrt == (mrtentry_t *)NULL) { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Mcast traceroute: no route entry %s", inet_fmt(qry->tr_src, s1, sizeof(s1))); if (IN_MULTICAST(ntohl(dst))) return; } vifi = find_vif_direct(qry->tr_dst); if (vifi == NO_VIF) { /* The traceroute destination is not on one of my subnet vifs. */ IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Destination %s not an interface", inet_fmt(qry->tr_dst, s1, sizeof(s1))); if (IN_MULTICAST(ntohl(dst))) return; errcode = TR_WRONG_IF; } else if (mrt != (mrtentry_t *)NULL && !VIFM_ISSET(vifi, mrt->oifs)) { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Destination %s not on forwarding tree for src %s", inet_fmt(qry->tr_dst, s1, sizeof(s1)), inet_fmt(qry->tr_src, s2, sizeof(s2))); if (IN_MULTICAST(ntohl(dst))) return; errcode = TR_WRONG_IF; } } else { /* * determine which interface the packet came in on * RESP packets travel hop-by-hop so this either traversed * a tunnel or came from a directly attached mrouter. */ if ((vifi = find_vif_direct(src)) == NO_VIF) { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Wrong interface for packet"); errcode = TR_WRONG_IF; } } /* Now that we've decided to send a response, save the qid */ oqid = qry->tr_qid; IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Sending traceroute response"); /* copy the packet to the sending buffer */ p = igmp_send_buf + IP_IGMP_HEADER_LEN + IGMP_MINLEN; bcopy(data, p, datalen); p += datalen; /* * If there is no room to insert our reply, coopt the previous hop * error indication to relay this fact. */ if (p + sizeof(struct tr_resp) > igmp_send_buf + SEND_BUF_SIZE) { resp = (struct tr_resp *)p - 1; resp->tr_rflags = TR_NO_SPACE; mrt = NULL; goto sendit; } /* * fill in initial response fields */ resp = (struct tr_resp *)p; memset(resp, 0, sizeof(struct tr_resp)); datalen += RLEN; resp->tr_qarr = htonl(((tp.tv_sec + JAN_1970) << 16) + ((tp.tv_usec << 10) / 15625)); resp->tr_rproto = PROTO_PIM; resp->tr_outaddr = (vifi == NO_VIF) ? dst : uvifs[vifi].uv_lcl_addr; resp->tr_fttl = (vifi == NO_VIF) ? 0 : uvifs[vifi].uv_threshold; resp->tr_rflags = errcode; /* * obtain # of packets out on interface */ v_req.vifi = vifi; if (vifi != NO_VIF && ioctl(udp_socket, SIOCGETVIFCNT, (char *)&v_req) >= 0) resp->tr_vifout = htonl(v_req.ocount); else resp->tr_vifout = 0xffffffff; /* * fill in scoping & pruning information */ /* TODO */ #if 0 if (mrt != (mrtentry_t *)NULL) for (gt = rt->rt_groups; gt; gt = gt->gt_next) { if (gt->gt_mcastgrp >= group) break; } else gt = NULL; if (gt && gt->gt_mcastgrp == group) { struct stable *st; for (st = gt->gt_srctbl; st; st = st->st_next) if (qry->tr_src == st->st_origin) break; sg_req.src.s_addr = qry->tr_src; sg_req.grp.s_addr = group; if (st && st->st_ctime != 0 && ioctl(udp_socket, SIOCGETSGCNT, (char *)&sg_req) >= 0) resp->tr_pktcnt = htonl(sg_req.pktcnt + st->st_savpkt); else resp->tr_pktcnt = htonl(st ? st->st_savpkt : 0xffffffff); if (VIFM_ISSET(vifi, gt->gt_scope)) resp->tr_rflags = TR_SCOPED; else if (gt->gt_prsent_timer) resp->tr_rflags = TR_PRUNED; else if (!VIFM_ISSET(vifi, gt->gt_grpmems)) if (VIFM_ISSET(vifi, rt->rt_children) && NBRM_ISSETMASK(uvifs[vifi].uv_nbrmap, rt->rt_subordinates)) /*XXX*/ resp->tr_rflags = TR_OPRUNED; else resp->tr_rflags = TR_NO_FWD; } else { if (scoped_addr(vifi, group)) resp->tr_rflags = TR_SCOPED; else if (rt && !VIFM_ISSET(vifi, rt->rt_children)) resp->tr_rflags = TR_NO_FWD; } #endif /* 0 */ /* * if no rte exists, set NO_RTE error */ if (mrt == (mrtentry_t *)NULL) { src = dst; /* the dst address of resp. pkt */ resp->tr_inaddr = 0; resp->tr_rflags = TR_NO_RTE; resp->tr_rmtaddr = 0; } else { /* get # of packets in on interface */ v_req.vifi = mrt->incoming; if (ioctl(udp_socket, SIOCGETVIFCNT, (char *)&v_req) >= 0) resp->tr_vifin = htonl(v_req.icount); else resp->tr_vifin = 0xffffffff; /* TODO MASK_TO_VAL(rt->rt_originmask, resp->tr_smask); */ src = uvifs[mrt->incoming].uv_lcl_addr; resp->tr_inaddr = src; if (mrt->upstream != (pim_nbr_entry_t *)NULL) parent_address = mrt->upstream->address; else parent_address = INADDR_ANY; resp->tr_rmtaddr = parent_address; if (!VIFM_ISSET(vifi, mrt->oifs)) { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Destination %s not on forwarding tree for src %s", inet_fmt(qry->tr_dst, s1, sizeof(s1)), inet_fmt(qry->tr_src, s2, sizeof(s2))); resp->tr_rflags = TR_WRONG_IF; } #if 0 if (rt->rt_metric >= UNREACHABLE) { resp->tr_rflags = TR_NO_RTE; /* Hack to send reply directly */ rt = NULL; } #endif /* 0 */ } sendit: /* * if metric is 1 or no. of reports is 1, send response to requestor * else send to upstream router. If the upstream router can't handle * mtrace, set an error code and send to requestor anyway. */ IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "rcount:%d, no:%d", rcount, no); if ((rcount + 1 == no) || (mrt == NULL) || (mrt->metric == 1)) { resptype = IGMP_MTRACE_RESP; dst = qry->tr_raddr; } else #if 0 /* TODO */ if (!can_mtrace(rt->rt_parent, rt->rt_gateway)) { dst = qry->tr_raddr; resp->tr_rflags = TR_OLD_ROUTER; resptype = IGMP_MTRACE_RESP; } else { #endif /* 0 */ if (mrt->upstream != (pim_nbr_entry_t *)NULL) parent_address = mrt->upstream->address; else parent_address = INADDR_ANY; dst = parent_address; resptype = IGMP_MTRACE; #if 0 /* TODO */ } #endif if (IN_MULTICAST(ntohl(dst))) { /* * Send the reply on a known multicast capable vif. * If we don't have one, we can't source any multicasts anyway. */ if (phys_vif != -1) { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Sending reply to %s from %s", inet_fmt(dst, s1, sizeof(s1)), inet_fmt(uvifs[phys_vif].uv_lcl_addr, s2, sizeof(s2))); k_set_ttl(igmp_socket, qry->tr_rttl); send_igmp(igmp_send_buf, uvifs[phys_vif].uv_lcl_addr, dst, resptype, no, group, datalen); k_set_ttl(igmp_socket, 1); } else logit(LOG_INFO, 0, "No enabled phyints -- %s", "dropping traceroute reply"); } else { IF_DEBUG(DEBUG_TRACE) logit(LOG_DEBUG, 0, "Sending %s to %s from %s", resptype == IGMP_MTRACE_RESP ? "reply" : "request on", inet_fmt(dst, s1, sizeof(s1)), inet_fmt(src, s2, sizeof(s2))); send_igmp(igmp_send_buf, src, dst, resptype, no, group, datalen); } }