/**
* Handles incoming membership reports, and
* appends them to the routing table.
*/
void acceptGroupReport(uint32_t src, uint32_t group, uint8_t type) {
struct IfDesc *sourceVif;
// Sanitycheck the group adress...
if(!IN_MULTICAST( ntohl(group) )) {
my_log(LOG_WARNING, 0, "The group address %s is not a valid Multicast group.",
inetFmt(group, s1));
return;
}
// Find the interface on which the report was recieved.
sourceVif = getIfByAddress( src );
if(sourceVif == NULL) {
my_log(LOG_WARNING, 0, "No interfaces found for source %s",
inetFmt(src,s1));
return;
}
if(sourceVif->InAdr.s_addr == src) {
my_log(LOG_NOTICE, 0, "The IGMP message was from myself. Ignoring.");
return;
}
// We have a IF so check that it's an downstream IF.
if(sourceVif->state == IF_STATE_DOWNSTREAM) {
my_log(LOG_DEBUG, 0, "Should insert group %s (from: %s) to route table. Vif Ix : %d",
inetFmt(group,s1), inetFmt(src,s2), sourceVif->index);
// If we don't have a whitelist we insertRoute and done
if(sourceVif->allowedgroups == NULL)
{
#ifdef RALINK_ESW_SUPPORT
insert_multicast_ip(ntohl(group), ntohl(src));
#endif
insertRoute(group, sourceVif->index);
return;
}
// Check if this Request is legit on this interface
struct SubnetList *sn;
for(sn = sourceVif->allowedgroups; sn != NULL; sn = sn->next)
if((group & sn->subnet_mask) == sn->subnet_addr)
{
#ifdef RALINK_ESW_SUPPORT
insert_multicast_ip(ntohl(group), ntohl(src));
#endif
// The membership report was OK... Insert it into the route table..
insertRoute(group, sourceVif->index);
return;
}
my_log(LOG_INFO, 0, "The group address %s may not be requested from this interface. Ignoring.", inetFmt(group, s1));
} else {
// Log the state of the interface the report was recieved on.
my_log(LOG_INFO, 0, "Mebership report was recieved on %s. Ignoring.",
sourceVif->state==IF_STATE_UPSTREAM?"the upstream interface":"a disabled interface");
}
}
/**
* Recieves and handles a group leave message.
*/
void acceptLeaveMessage(uint32_t src, uint32_t group) {
struct IfDesc *sourceVif;
my_log(LOG_DEBUG, 0,
"Got leave message from %s to %s. Starting last member detection.",
inetFmt(src, s1), inetFmt(group, s2));
// Sanitycheck the group adress...
if(!IN_MULTICAST( ntohl(group) )) {
my_log(LOG_WARNING, 0, "The group address %s is not a valid Multicast group.",
inetFmt(group, s1));
return;
}
// Find the interface on which the report was recieved.
sourceVif = getIfByAddress( src );
if(sourceVif == NULL) {
my_log(LOG_WARNING, 0, "No interfaces found for source %s",
inetFmt(src,s1));
return;
}
// We have a IF so check that it's an downstream IF.
if(sourceVif->state == IF_STATE_DOWNSTREAM) {
GroupVifDesc *gvDesc;
gvDesc = (GroupVifDesc*) malloc(sizeof(GroupVifDesc));
// Tell the route table that we are checking for remaining members...
setRouteLastMemberMode(group);
// Call the group spesific membership querier...
gvDesc->group = group;
gvDesc->vifAddr = sourceVif->InAdr.s_addr;
gvDesc->started = 0;
sendGroupSpecificMemberQuery(gvDesc);
#ifdef RALINK_ESW_SUPPORT
remove_member(ntohl(group), ntohl(src));
#endif
} else {
// just ignore the leave request...
my_log(LOG_DEBUG, 0, "The found if for %s was not downstream. Ignoring leave request.", inetFmt(src, s1));
}
}
/**
* Handles incoming membership reports, and
* appends them to the routing table.
*/
void acceptGroupReport(uint32_t src, uint32_t group, uint8_t type) {
struct IfDesc *sourceVif;
// Sanitycheck the group adress...
if(!IN_MULTICAST( ntohl(group) )) {
my_log(LOG_WARNING, 0, "The group address %s is not a valid Multicast group.",
inetFmt(group, s1));
return;
}
// Find the interface on which the report was recieved.
sourceVif = getIfByAddress( src );
if(sourceVif == NULL) {
my_log(LOG_WARNING, 0, "No interfaces found for source %s",
inetFmt(src,s1));
return;
}
if(sourceVif->InAdr.s_addr == src) {
my_log(LOG_NOTICE, 0, "The IGMP message was from myself. Ignoring.");
return;
}
// We have a IF so check that it's an downstream IF.
if(sourceVif->state == IF_STATE_DOWNSTREAM) {
my_log(LOG_DEBUG, 0, "Should insert group %s (from: %s) to route table. Vif Ix : %d",
inetFmt(group,s1), inetFmt(src,s2), sourceVif->index);
// The membership report was OK... Insert it into the route table..
insertRoute(group, sourceVif->index);
} else {
// Log the state of the interface the report was recieved on.
my_log(LOG_INFO, 0, "Membership report was recieved on %s. Ignoring.",
sourceVif->state==IF_STATE_UPSTREAM?"the upstream interface":"a disabled interface");
}
}
/**
* Accept a V3 Membership Report
*/
void acceptV3GroupReport(uint32_t src, uint8_t type, struct igmpv3_groupreport* igmpv3rep) {
struct IfDesc *sourceVif;
// Sanitycheck the group adress...
if(!IN_MULTICAST( ntohl(group) )) {
my_log(LOG_WARNING, 0, "The group address %s is not a valid Multicast group.",
inetFmt(group, s1));
return;
}
// Find the interface on which the report was recieved.
sourceVif = getIfByAddress( src );
if(sourceVif == NULL) {
my_log(LOG_WARNING, 0, "No interfaces found for source %s",
inetFmt(src,s1));
return;
}
if(sourceVif->InAdr.s_addr == src) {
my_log(LOG_NOTICE, 0, "The IGMP message was from myself. Ignoring.");
return;
}
// We have a IF so check that it's an downstream IF.
if(sourceVif->state != IF_STATE_DOWNSTREAM) {
// Log the state of the interface the report was recieved on.
my_log(LOG_INFO, 0, "Membership report was recieved on %s. Ignoring.",
sourceVif->state==IF_STATE_UPSTREAM?"the upstream interface":"a disabled interface");
} else {
my_log(LOG_DEBUG, 0, "IGMPv3 Membership Report")
// TODO: Can we batch-report here?
uint16_t num_entries = ntohl(igmpv3rep->num_entries);
uint16_t eix = 0;
while ( eix < num_entries )
{
struct igmpv3_groupreport_entry* e = (struct igmpv3_groupreport_entry* igmpv3rep->grec) + eix;
uint16_t num_sources = ntohl(e->nsrcs);
uint16_t six = 0;
while ( six < num_sources )
{
uint32_t* srcgroup = (uint32_t* e->sources) + six;
group = ntohl(*srcgroup);
switch ( e->type == 0x0 )
{
case IGMPV3_GRE_MODE_INCLUDE:
case IGMPV3_GRE_CHMODE_INCLUDE:
case IGMPV3_GRE_ALLOW_NEW_SOURCES:
my_log(LOG_DEBUG, 0, "IGMPv3 Subscribe to %s.",
inetFmt(group, s1));
insertRoute(group, sourceVif->index);
break;
case IGMPV3_GRE_MODE_EXCLUDE:
case IGMPV3_GRE_CHMODE_EXCLUDE:
case IGMPV3_GRE_BLOCK_OLD_SOURCES:
my_log(LOG_DEBUG, 0, "IGMPv3 Unsubscribe from %s.",
inetFmt(group, s1));
deleteRoute(group, sourceVif->index);
break;
default:
my_log(LOG_INFO, 0, "Membership V3 group report received with unknown type %d.", e->type);
}
};
eix++;
};
return;
}
}
/**
* Process a newly received IGMP packet that is sitting in the input
* packet buffer.
*/
void acceptIgmp(int recvlen) {
register uint32_t src, dst, group;
struct ip *ip;
struct igmp *igmp;
int ipdatalen, iphdrlen, igmpdatalen;
if (recvlen < sizeof(struct ip)) {
my_log(LOG_WARNING, 0,
"received packet too short (%u bytes) for IP header", recvlen);
return;
}
ip = (struct ip *)recv_buf;
src = ip->ip_src.s_addr;
dst = ip->ip_dst.s_addr;
/* filter local multicast 239.255.255.250 */
if (dst == htonl(0xEFFFFFFA))
{
my_log(LOG_NOTICE, 0, "The IGMP message was local multicast. Ignoring.");
return;
}
/*
* this is most likely a message from the kernel indicating that
* a new src grp pair message has arrived and so, it would be
* necessary to install a route into the kernel for this.
*/
if (ip->ip_p == 0) {
if (src == 0 || dst == 0) {
my_log(LOG_WARNING, 0, "kernel request not accurate");
}
else {
struct IfDesc *checkVIF;
// Check if the source address matches a valid address on upstream vif.
checkVIF = getIfByIx( upStreamVif );
if(checkVIF == 0) {
my_log(LOG_WARNING, 0, "Upstream VIF was null.");
return;
}
else if(src == checkVIF->InAdr.s_addr) {
my_log(LOG_NOTICE, 0, "Route activation request from %s for %s is from myself. Ignoring.",
inetFmt(src, s1), inetFmt(dst, s2));
return;
}
else if(!isAdressValidForIf(checkVIF, src)) {
struct IfDesc *downVIF = getIfByAddress(src);
if (downVIF && downVIF->state & IF_STATE_DOWNSTREAM) {
my_log(LOG_NOTICE, 0, "The source address %s for group %s is from downstream VIF. Ignoring.",
inetFmt(src, s1), inetFmt(dst, s2));
} else {
my_log(LOG_WARNING, 0, "The source address %s for group %s, is not in any valid net for upstream VIF.",
inetFmt(src, s1), inetFmt(dst, s2));
}
return;
}
// Activate the route.
my_log(LOG_DEBUG, 0, "Route activate request from %s to %s",
inetFmt(src,s1), inetFmt(dst,s2));
activateRoute(dst, src);
}
return;
}
iphdrlen = ip->ip_hl << 2;
ipdatalen = ip_data_len(ip);
if (iphdrlen + ipdatalen != recvlen) {
my_log(LOG_WARNING, 0,
"received packet from %s shorter (%u bytes) than hdr+data length (%u+%u)",
inetFmt(src, s1), recvlen, iphdrlen, ipdatalen);
return;
}
igmp = (struct igmp *)(recv_buf + iphdrlen);
group = igmp->igmp_group.s_addr;
igmpdatalen = ipdatalen - IGMP_MINLEN;
if (igmpdatalen < 0) {
my_log(LOG_WARNING, 0,
"received IP data field too short (%u bytes) for IGMP, from %s",
ipdatalen, inetFmt(src, s1));
return;
}
my_log(LOG_NOTICE, 0, "RECV %s from %-15s to %s",
igmpPacketKind(igmp->igmp_type, igmp->igmp_code),
inetFmt(src, s1), inetFmt(dst, s2) );
switch (igmp->igmp_type) {
case IGMP_V1_MEMBERSHIP_REPORT:
case IGMP_V2_MEMBERSHIP_REPORT:
acceptGroupReport(src, group, igmp->igmp_type);
return;
case IGMP_V2_LEAVE_GROUP:
acceptLeaveMessage(src, group);
return;
case IGMP_MEMBERSHIP_QUERY:
return;
default:
my_log(LOG_INFO, 0,
"ignoring unknown IGMP message type %x from %s to %s",
igmp->igmp_type, inetFmt(src, s1),
inetFmt(dst, s2));
return;
}
}
