#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/protosw.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/igmp.h>
#include <netinet/igmp_var.h>
#ifndef __APPLE__
static MALLOC_DEFINE(M_IGMP, "igmp", "igmp state");
#endif
static struct router_info *
find_rti __P((struct ifnet *ifp));
static struct igmpstat igmpstat;
SYSCTL_STRUCT(_net_inet_igmp, IGMPCTL_STATS, stats, CTLFLAG_RD,
&igmpstat, igmpstat, "");
static int igmp_timers_are_running;
static u_long igmp_all_hosts_group;
static u_long igmp_all_rtrs_group;
static struct mbuf *router_alert;
static struct router_info *Head;
static void igmp_sendpkt __P((struct in_multi *, int, unsigned long));
void
igmp_init()
{
struct ipoption *ra;
igmp_all_hosts_group = htonl(INADDR_ALLHOSTS_GROUP);
igmp_all_rtrs_group = htonl(INADDR_ALLRTRS_GROUP);
igmp_timers_are_running = 0;
MGET(router_alert, M_DONTWAIT, MT_DATA);
ra = mtod(router_alert, struct ipoption *);
ra->ipopt_dst.s_addr = 0;
ra->ipopt_list[0] = IPOPT_RA;
ra->ipopt_list[1] = 0x04;
ra->ipopt_list[2] = 0x00;
ra->ipopt_list[3] = 0x00;
router_alert->m_len = sizeof(ra->ipopt_dst) + ra->ipopt_list[1];
Head = (struct router_info *) 0;
}
static struct router_info *
find_rti(ifp)
struct ifnet *ifp;
{
register struct router_info *rti = Head;
#if IGMP_DEBUG
printf("[igmp.c, _find_rti] --> entering \n");
#endif
while (rti) {
if (rti->rti_ifp == ifp) {
#if IGMP_DEBUG
printf("[igmp.c, _find_rti] --> found old entry \n");
#endif
return rti;
}
rti = rti->rti_next;
}
MALLOC(rti, struct router_info *, sizeof *rti, M_IGMP, M_NOWAIT);
rti->rti_ifp = ifp;
rti->rti_type = IGMP_V2_ROUTER;
rti->rti_time = 0;
rti->rti_next = Head;
Head = rti;
#if IGMP_DEBUG
printf("[igmp.c, _find_rti] --> created an entry \n");
#endif
return rti;
}
void
igmp_input(m, iphlen)
register struct mbuf *m;
register int iphlen;
{
register struct igmp *igmp;
register struct ip *ip;
register int igmplen;
register struct ifnet *ifp = m->m_pkthdr.rcvif;
register int minlen;
register struct in_multi *inm;
register struct in_ifaddr *ia;
struct in_multistep step;
struct router_info *rti;
int timer;
++igmpstat.igps_rcv_total;
ip = mtod(m, struct ip *);
igmplen = ip->ip_len;
if (igmplen < IGMP_MINLEN) {
++igmpstat.igps_rcv_tooshort;
m_freem(m);
return;
}
minlen = iphlen + IGMP_MINLEN;
if ((m->m_flags & M_EXT || m->m_len < minlen) &&
(m = m_pullup(m, minlen)) == 0) {
++igmpstat.igps_rcv_tooshort;
return;
}
m->m_data += iphlen;
m->m_len -= iphlen;
igmp = mtod(m, struct igmp *);
if (in_cksum(m, igmplen)) {
++igmpstat.igps_rcv_badsum;
m_freem(m);
return;
}
m->m_data -= iphlen;
m->m_len += iphlen;
ip = mtod(m, struct ip *);
timer = igmp->igmp_code * PR_FASTHZ / IGMP_TIMER_SCALE;
if (timer == 0)
timer = 1;
rti = find_rti(ifp);
switch (igmp->igmp_type) {
case IGMP_MEMBERSHIP_QUERY:
++igmpstat.igps_rcv_queries;
if (ifp->if_flags & IFF_LOOPBACK)
break;
if (igmp->igmp_code == 0) {
rti->rti_type = IGMP_V1_ROUTER;
rti->rti_time = 0;
timer = IGMP_MAX_HOST_REPORT_DELAY * PR_FASTHZ;
if (ip->ip_dst.s_addr != igmp_all_hosts_group ||
igmp->igmp_group.s_addr != 0) {
++igmpstat.igps_rcv_badqueries;
m_freem(m);
return;
}
} else {
if (igmp->igmp_group.s_addr != 0 &&
!IN_MULTICAST(ntohl(igmp->igmp_group.s_addr))) {
++igmpstat.igps_rcv_badqueries;
m_freem(m);
return;
}
}
IN_FIRST_MULTI(step, inm);
while (inm != NULL) {
if (inm->inm_ifp == ifp &&
inm->inm_addr.s_addr != igmp_all_hosts_group &&
(igmp->igmp_group.s_addr == 0 ||
igmp->igmp_group.s_addr == inm->inm_addr.s_addr)) {
if (inm->inm_timer == 0 ||
inm->inm_timer > timer) {
inm->inm_timer =
IGMP_RANDOM_DELAY(timer);
igmp_timers_are_running = 1;
}
}
IN_NEXT_MULTI(step, inm);
}
break;
case IGMP_V1_MEMBERSHIP_REPORT:
case IGMP_V2_MEMBERSHIP_REPORT:
IFP_TO_IA(ifp, ia);
if (ia && ip->ip_src.s_addr == IA_SIN(ia)->sin_addr.s_addr)
break;
++igmpstat.igps_rcv_reports;
if (ifp->if_flags & IFF_LOOPBACK)
break;
if (!IN_MULTICAST(ntohl(igmp->igmp_group.s_addr))) {
++igmpstat.igps_rcv_badreports;
m_freem(m);
return;
}
if ((ntohl(ip->ip_src.s_addr) & IN_CLASSA_NET) == 0)
if (ia) ip->ip_src.s_addr = htonl(ia->ia_subnet);
IN_LOOKUP_MULTI(igmp->igmp_group, ifp, inm);
if (inm != NULL) {
inm->inm_timer = 0;
++igmpstat.igps_rcv_ourreports;
inm->inm_state = IGMP_OTHERMEMBER;
}
break;
}
rip_input(m, iphlen);
}
void
igmp_joingroup(inm)
struct in_multi *inm;
{
int s = splnet();
if (inm->inm_addr.s_addr == igmp_all_hosts_group
|| inm->inm_ifp->if_flags & IFF_LOOPBACK) {
inm->inm_timer = 0;
inm->inm_state = IGMP_OTHERMEMBER;
} else {
inm->inm_rti = find_rti(inm->inm_ifp);
igmp_sendpkt(inm, inm->inm_rti->rti_type, 0);
inm->inm_timer = IGMP_RANDOM_DELAY(
IGMP_MAX_HOST_REPORT_DELAY*PR_FASTHZ);
inm->inm_state = IGMP_IREPORTEDLAST;
igmp_timers_are_running = 1;
}
splx(s);
}
void
igmp_leavegroup(inm)
struct in_multi *inm;
{
if (inm->inm_state == IGMP_IREPORTEDLAST &&
inm->inm_addr.s_addr != igmp_all_hosts_group &&
!(inm->inm_ifp->if_flags & IFF_LOOPBACK) &&
inm->inm_rti->rti_type != IGMP_V1_ROUTER)
igmp_sendpkt(inm, IGMP_V2_LEAVE_GROUP, igmp_all_rtrs_group);
}
void
igmp_fasttimo()
{
register struct in_multi *inm;
struct in_multistep step;
int s;
if (!igmp_timers_are_running)
return;
s = splnet();
igmp_timers_are_running = 0;
IN_FIRST_MULTI(step, inm);
while (inm != NULL) {
if (inm->inm_timer == 0) {
} else if (--inm->inm_timer == 0) {
igmp_sendpkt(inm, inm->inm_rti->rti_type, 0);
inm->inm_state = IGMP_IREPORTEDLAST;
} else {
igmp_timers_are_running = 1;
}
IN_NEXT_MULTI(step, inm);
}
splx(s);
}
void
igmp_slowtimo()
{
int s = splnet();
register struct router_info *rti = Head;
#if IGMP_DEBUG
printf("[igmp.c,_slowtimo] -- > entering \n");
#endif
while (rti) {
if (rti->rti_type == IGMP_V1_ROUTER) {
rti->rti_time++;
if (rti->rti_time >= IGMP_AGE_THRESHOLD) {
rti->rti_type = IGMP_V2_ROUTER;
}
}
rti = rti->rti_next;
}
#if IGMP_DEBUG
printf("[igmp.c,_slowtimo] -- > exiting \n");
#endif
splx(s);
}
static struct route igmprt;
static void
igmp_sendpkt(inm, type, addr)
struct in_multi *inm;
int type;
unsigned long addr;
{
struct mbuf *m;
struct igmp *igmp;
struct ip *ip;
struct ip_moptions imo;
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (m == NULL)
return;
m->m_pkthdr.rcvif = loif;
m->m_pkthdr.len = sizeof(struct ip) + IGMP_MINLEN;
MH_ALIGN(m, IGMP_MINLEN + sizeof(struct ip));
m->m_data += sizeof(struct ip);
m->m_len = IGMP_MINLEN;
m->m_pkthdr.csum_flags = 0;
m->m_pkthdr.csum_data = 0;
igmp = mtod(m, struct igmp *);
igmp->igmp_type = type;
igmp->igmp_code = 0;
igmp->igmp_group = inm->inm_addr;
igmp->igmp_cksum = 0;
igmp->igmp_cksum = in_cksum(m, IGMP_MINLEN);
m->m_data -= sizeof(struct ip);
m->m_len += sizeof(struct ip);
ip = mtod(m, struct ip *);
ip->ip_tos = 0;
ip->ip_len = sizeof(struct ip) + IGMP_MINLEN;
ip->ip_off = 0;
ip->ip_p = IPPROTO_IGMP;
ip->ip_src.s_addr = INADDR_ANY;
ip->ip_dst.s_addr = addr ? addr : igmp->igmp_group.s_addr;
imo.imo_multicast_ifp = inm->inm_ifp;
imo.imo_multicast_ttl = 1;
imo.imo_multicast_vif = -1;
imo.imo_multicast_loop = (ip_mrouter != NULL);
ip_output(m, router_alert, &igmprt, 0, &imo);
++igmpstat.igps_snd_reports;
}