Multicast propagation is now working from non-supernodes, and working quite well. Time for some more simulation before 0.5.0!

1 files changed, 39 insertions, 25 deletions

diff --git a/node/PacketDecoder.cpp b/node/PacketDecoder.cpp
index 0533ebda..be7acf8d 100644
--- a/node/PacketDecoder.cpp
+++ b/node/PacketDecoder.cpp
@@ -25,6 +25,10 @@
  * LLC. Start here: http://www.zerotier.com/
  */
 
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
 #include "../version.h"
 
 #include "Constants.hpp"
@@ -463,23 +467,27 @@ bool PacketDecoder::_doMULTICAST_FRAME(const RuntimeEnvironment *_r,const Shared
 			return false;
 		}
 
+		// These fields change
 		unsigned int depth = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_DEPTH);
-		unsigned char *fifo = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_FIFO,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_PROPAGATION_FIFO);
-		unsigned char *bloom = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_BLOOM,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_PROPAGATION_BLOOM);
-		uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_NETWORK_ID);
-		uint16_t bloomNonce = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_BLOOM_NONCE);
-		unsigned int prefixBits = (*this)[ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_PREFIX_BITS];
-		unsigned int prefix = (*this)[ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_PREFIX];
-		uint64_t guid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_GUID);
-		MAC sourceMac(field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_SOURCE_MAC,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_SOURCE_MAC));
-		MulticastGroup dest(MAC(field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_DEST_MAC,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_DEST_MAC)),at<uint32_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_DEST_ADI));
-		unsigned int etherType = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_ETHERTYPE);
-		unsigned int frameLen = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME_LEN);
-		unsigned char *frame = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME,frameLen);
-		unsigned int signatureLen = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME + frameLen);
-		unsigned char *signature = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME + frameLen + 2,signatureLen);
-
-		unsigned int signedPartLen = (ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME - ZT_PROTO_VERB_MULTICAST_FRAME_IDX__START_OF_SIGNED_PORTION) + frameLen;
+		unsigned char *const fifo = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_FIFO,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_PROPAGATION_FIFO);
+		unsigned char *const bloom = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_BLOOM,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_PROPAGATION_BLOOM);
+
+		// These fields don't -- they're signed by the original sender
+		// const unsigned int flags = (*this)[ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FLAGS];
+		const uint64_t nwid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_NETWORK_ID);
+		const uint16_t bloomNonce = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_BLOOM_NONCE);
+		const unsigned int prefixBits = (*this)[ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_PREFIX_BITS];
+		const unsigned int prefix = (*this)[ZT_PROTO_VERB_MULTICAST_FRAME_IDX_PROPAGATION_PREFIX];
+		const uint64_t guid = at<uint64_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_GUID);
+		const MAC sourceMac(field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_SOURCE_MAC,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_SOURCE_MAC));
+		const MulticastGroup dest(MAC(field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_DEST_MAC,ZT_PROTO_VERB_MULTICAST_FRAME_LEN_DEST_MAC)),at<uint32_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_DEST_ADI));
+		const unsigned int etherType = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_ETHERTYPE);
+		const unsigned int frameLen = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME_LEN);
+		const unsigned char *const frame = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME,frameLen);
+		const unsigned int signatureLen = at<uint16_t>(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME + frameLen);
+		const unsigned char *const signature = field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME + frameLen + 2,signatureLen);
+
+		const unsigned int signedPartLen = (ZT_PROTO_VERB_MULTICAST_FRAME_IDX_FRAME - ZT_PROTO_VERB_MULTICAST_FRAME_IDX__START_OF_SIGNED_PORTION) + frameLen;
 		if (!originPeer->identity().verify(field(ZT_PROTO_VERB_MULTICAST_FRAME_IDX__START_OF_SIGNED_PORTION,signedPartLen),signedPartLen,signature,signatureLen)) {
 			TRACE("dropped MULTICAST_FRAME from %s(%s): failed signature verification, claims to be from %s",source().toString().c_str(),_remoteAddress.toString().c_str(),origin.toString().c_str());
 			return true;
@@ -491,6 +499,7 @@ bool PacketDecoder::_doMULTICAST_FRAME(const RuntimeEnvironment *_r,const Shared
 		_r->demarc->send(Demarc::ANY_PORT,ZT_DEFAULTS.multicastTraceWatcher,mct,strlen(mct),-1);
 #endif
 
+		// Security check to prohibit multicasts that are really Ethernet unicasts
 		if (!dest.mac().isMulticast()) {
 			TRACE("dropped MULTICAST_FRAME from %s(%s): %s is not a multicast/broadcast address",source().toString().c_str(),_remoteAddress.toString().c_str(),dest.mac().toString().c_str());
 			return true;
@@ -564,15 +573,20 @@ bool PacketDecoder::_doMULTICAST_FRAME(const RuntimeEnvironment *_r,const Shared
 		// New FIFO with room for one extra, since head will be next hop
 		unsigned char newFifo[ZT_PROTO_VERB_MULTICAST_FRAME_LEN_PROPAGATION_FIFO + ZT_ADDRESS_LENGTH];
 		unsigned char *newFifoPtr = newFifo;
-		unsigned char *const newFifoEnd = newFifoPtr + sizeof(newFifo);
-		for(unsigned int i=0;i<ZT_PROTO_VERB_MULTICAST_FRAME_LEN_PROPAGATION_FIFO;) {
-			unsigned int j = i;
-			i += ZT_ADDRESS_LENGTH;
-			unsigned char zm = 0;
-			while (j != i)
-				zm |= (*(newFifoPtr++) = fifo[j++]);
-			if (!zm) // stop at zero address
-				break;
+		unsigned char *const newFifoEnd = newFifo + sizeof(newFifo);
+
+		// Copy old FIFO into new buffer, terminating at first NULL address
+		for(unsigned char *f=fifo,*const fifoEnd=(fifo + ZT_PROTO_VERB_MULTICAST_FRAME_LEN_PROPAGATION_FIFO);f!=fifoEnd;) {
+			unsigned char *nf = newFifoPtr;
+			unsigned char *e = nf + ZT_ADDRESS_LENGTH;
+			unsigned char *ftmp = f;
+			unsigned char zeroCheckMask = 0;
+			while (nf != e)
+				zeroCheckMask |= (*(nf++) = *(ftmp++));
+			if (zeroCheckMask) {
+				f = ftmp;
+				newFifoPtr = nf;
+			} else break;
 		}
 
 		// Add any next hops we know about to FIFO