/*
* 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);
}
}
