From 451b8aa7b293be0bdd62a0cc1c292bfe5b3de751 Mon Sep 17 00:00:00 2001
From: Adam Ierymenko <adam.ierymenko@gmail.com>
Date: Tue, 10 Nov 2015 17:37:38 -0800
Subject: [PATCH] Query both root and network controller for multicast last
 resort GATHER.

---
 node/Cluster.cpp       | 27 ---------------------------
 node/Cluster.hpp       | 27 +++++++++++++++++++++++++++
 node/Multicaster.cpp   | 18 +++++++++++-------
 service/OneService.cpp |  2 +-
 4 files changed, 39 insertions(+), 35 deletions(-)

diff --git a/node/Cluster.cpp b/node/Cluster.cpp
index 0a7de93d4..af9ab8543 100644
--- a/node/Cluster.cpp
+++ b/node/Cluster.cpp
@@ -55,33 +55,6 @@
 #include "Node.hpp"
 #include "Array.hpp"
 
-/**
- * Chunk size for allocating queue entries
- *
- * Queue entries are allocated in chunks of this many and are added to a pool.
- * ZT_CLUSTER_MAX_QUEUE_GLOBAL must be evenly divisible by this.
- */
-#define ZT_CLUSTER_QUEUE_CHUNK_SIZE 32
-
-/**
- * Maximum number of chunks to ever allocate
- *
- * This is a global sanity limit to prevent resource exhaustion attacks. It
- * works out to about 600mb of RAM. You'll never see this on a normal edge
- * node. We're unlikely to see this on a root server unless someone is DOSing
- * us. In that case cluster relaying will be affected but other functions
- * should continue to operate normally.
- */
-#define ZT_CLUSTER_MAX_QUEUE_CHUNKS 8194
-
-/**
- * Max data per queue entry
- *
- * If we ever support larger transport MTUs this must be increased. The plus
- * 16 is just a small margin and has no special meaning.
- */
-#define ZT_CLUSTER_SEND_QUEUE_DATA_MAX (ZT_UDP_DEFAULT_PAYLOAD_MTU + 16)
-
 namespace ZeroTier {
 
 static inline double _dist3d(int x1,int y1,int z1,int x2,int y2,int z2)
diff --git a/node/Cluster.hpp b/node/Cluster.hpp
index 87452b6f3..ccf0c12a4 100644
--- a/node/Cluster.hpp
+++ b/node/Cluster.hpp
@@ -73,6 +73,33 @@
  */
 #define ZT_CLUSTER_QUEUE_EXPIRATION 5000
 
+/**
+ * Chunk size for allocating queue entries
+ *
+ * Queue entries are allocated in chunks of this many and are added to a pool.
+ * ZT_CLUSTER_MAX_QUEUE_GLOBAL must be evenly divisible by this.
+ */
+#define ZT_CLUSTER_QUEUE_CHUNK_SIZE 32
+
+/**
+ * Maximum number of chunks to ever allocate
+ *
+ * This is a global sanity limit to prevent resource exhaustion attacks. It
+ * works out to about 600mb of RAM. You'll never see this on a normal edge
+ * node. We're unlikely to see this on a root server unless someone is DOSing
+ * us. In that case cluster relaying will be affected but other functions
+ * should continue to operate normally.
+ */
+#define ZT_CLUSTER_MAX_QUEUE_CHUNKS 8194
+
+/**
+ * Max data per queue entry
+ *
+ * If we ever support larger transport MTUs this must be increased. The plus
+ * 16 is just a small margin and has no special meaning.
+ */
+#define ZT_CLUSTER_SEND_QUEUE_DATA_MAX (ZT_UDP_DEFAULT_PAYLOAD_MTU + 16)
+
 namespace ZeroTier {
 
 class RuntimeEnvironment;
diff --git a/node/Multicaster.cpp b/node/Multicaster.cpp
index 41838552d..fa9487eff 100644
--- a/node/Multicaster.cpp
+++ b/node/Multicaster.cpp
@@ -235,21 +235,26 @@ void Multicaster::send(
 
 			if ((gs.members.empty())||((now - gs.lastExplicitGather) >= ZT_MULTICAST_EXPLICIT_GATHER_DELAY)) {
 				gs.lastExplicitGather = now;
-				SharedPtr<Peer> r(RR->topology->getBestRoot());
-				if (r) {
-					TRACE(">>MC upstream GATHER up to %u for group %.16llx/%s",gatherLimit,nwid,mg.toString().c_str());
+				SharedPtr<Peer> explicitGatherPeers[2];
+				explicitGatherPeers[0] = RR->topology->getBestRoot();
+				explicitGatherPeers[1] = RR->topology->getPeer(Network::controllerFor(nwid));
+				for(unsigned int k=0;k<2;++k) {
+					const SharedPtr<Peer> &p = explicitGatherPeers[k];
+					if (!p)
+						continue;
+					//TRACE(">>MC upstream GATHER up to %u for group %.16llx/%s",gatherLimit,nwid,mg.toString().c_str());
 
 					const CertificateOfMembership *com = (CertificateOfMembership *)0;
 					{
 						SharedPtr<Network> nw(RR->node->network(nwid));
 						if (nw) {
 							SharedPtr<NetworkConfig> nconf(nw->config2());
-							if ((nconf)&&(nconf->com())&&(nconf->isPrivate())&&(r->needsOurNetworkMembershipCertificate(nwid,now,true)))
+							if ((nconf)&&(nconf->com())&&(nconf->isPrivate())&&(p->needsOurNetworkMembershipCertificate(nwid,now,true)))
 								com = &(nconf->com());
 						}
 					}
 
-					Packet outp(r->address(),RR->identity.address(),Packet::VERB_MULTICAST_GATHER);
+					Packet outp(p->address(),RR->identity.address(),Packet::VERB_MULTICAST_GATHER);
 					outp.append(nwid);
 					outp.append((uint8_t)(com ? 0x01 : 0x00));
 					mg.mac().appendTo(outp);
@@ -257,8 +262,7 @@ void Multicaster::send(
 					outp.append((uint32_t)gatherLimit);
 					if (com)
 						com->serialize(outp);
-					outp.armor(r->key(),true);
-					r->send(RR,outp.data(),outp.size(),now);
+					RR->sw->send(outp,true,0);
 				}
 				gatherLimit = 0;
 			}
diff --git a/service/OneService.cpp b/service/OneService.cpp
index 44926a94e..87f4136ca 100644
--- a/service/OneService.cpp
+++ b/service/OneService.cpp
@@ -1265,7 +1265,7 @@ public:
 						_phy.setIp4UdpTtl(_v4UpnpUdpSocket,ttl);
 					const int result = ((_phy.udpSend(_v4UpnpUdpSocket,(const struct sockaddr *)addr,data,len) != 0) ? 0 : -1);
 					if (ttl)
-						_phy.setIp4UdlTtl(_v4UpnpUdpSocket,255);
+						_phy.setIp4UdpTtl(_v4UpnpUdpSocket,255);
 					return result;
 				} else {
 					return -1;