Eliminate some poorly thought out optimizations from the netconf/controller interaction,

and go ahead and bump version to 1.0.4.

For a while in 1.0.3 -dev I was trying to optimize out repeated network controller
requests by using a ratcheting mechanism. If the client received a network config
that was indeed different from the one it had, it would respond by instantlly
requesting it again.

Not sure what I was thinking. It's fundamentally unsafe to respond to a message
with another message of the same type -- it risks a race condition. In this case
that's exactly what could happen.

It just isn't worth the added complexity to avoid a tiny, tiny amount of network
overhead, so I've taken this whole path out.

A few extra bytes every two minutes isn't worth fretting about, but as I recall
the reason for this optimization was to save CPU on the controller. This can be
achieved by just caching responses in memory *there* and serving those same
responses back out if they haven't changed.

I think I developed that 'ratcheting' stuff before I went full time on this. It's
hard to develop stuff like this without hours of sustained focus.

1 files changed, 7 insertions, 24 deletions

diff --git a/node/IncomingPacket.cpp b/node/IncomingPacket.cpp
index ae99352e..c3d8cc6d 100644
--- a/node/IncomingPacket.cpp
+++ b/node/IncomingPacket.cpp
@@ -392,28 +392,7 @@ bool IncomingPacket::_doOK(const RuntimeEnvironment *RR,const SharedPtr<Peer> &p
 					const unsigned int dictlen = at<uint16_t>(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST__OK__IDX_DICT_LEN);
 					const std::string dict((const char *)field(ZT_PROTO_VERB_NETWORK_CONFIG_REQUEST__OK__IDX_DICT,dictlen),dictlen);
 					if (dict.length()) {
-						if (nw->setConfiguration(Dictionary(dict)) == 2) { // 2 == accepted and actually new
-							/* If this configuration was indeed new, we do another
-							 * controller request with its revision. We do this in
-							 * order to (a) tell the network controller we got it (it
-							 * won't send a duplicate if ts == current), and (b)
-							 * get another one if the controller is changing rapidly
-							 * until we finally have the final version.
-							 *
-							 * Note that we don't do this for network controllers with
-							 * versions <= 1.0.3, since those regenerate a new controller
-							 * with a new revision every time. In that case this double
-							 * confirmation would create a race condition. */
-							const SharedPtr<NetworkConfig> nc(nw->config2());
-							if ((peer->atLeastVersion(1,0,3))&&(nc)&&(nc->revision() > 0)) {
-								Packet outp(peer->address(),RR->identity.address(),Packet::VERB_NETWORK_CONFIG_REQUEST);
-								outp.append((uint64_t)nw->id());
-								outp.append((uint16_t)0); // no meta-data
-								outp.append((uint64_t)nc->revision());
-								outp.armor(peer->key(),true);
-								RR->node->putPacket(_remoteAddress,outp.data(),outp.size());
-							}
-						}
+						nw->setConfiguration(Dictionary(dict));
 						TRACE("got network configuration for network %.16llx from %s",(unsigned long long)nw->id(),source().toString().c_str());
 					}
 				}
@@ -692,6 +671,7 @@ bool IncomingPacket::_doNETWORK_CONFIG_REQUEST(const RuntimeEnvironment *RR,cons
 		if (RR->localNetworkController) {
 			Dictionary netconf;
 			switch(RR->localNetworkController->doNetworkConfigRequest((h > 0) ? InetAddress() : _remoteAddress,RR->identity,peer->identity(),nwid,metaData,haveRevision,netconf)) {
+
 				case NetworkController::NETCONF_QUERY_OK: {
 					const std::string netconfStr(netconf.toString());
 					if (netconfStr.length() > 0xffff) { // sanity check since field ix 16-bit
@@ -712,8 +692,7 @@ bool IncomingPacket::_doNETWORK_CONFIG_REQUEST(const RuntimeEnvironment *RR,cons
 						}
 					}
 				}	break;
-				case NetworkController::NETCONF_QUERY_OK_BUT_NOT_NEWER: // nothing to do -- netconf has not changed
-					break;
+
 				case NetworkController::NETCONF_QUERY_OBJECT_NOT_FOUND: {
 					Packet outp(peer->address(),RR->identity.address(),Packet::VERB_ERROR);
 					outp.append((unsigned char)Packet::VERB_NETWORK_CONFIG_REQUEST);
@@ -723,6 +702,7 @@ bool IncomingPacket::_doNETWORK_CONFIG_REQUEST(const RuntimeEnvironment *RR,cons
 					outp.armor(peer->key(),true);
 					RR->node->putPacket(_remoteAddress,outp.data(),outp.size());
 				}	break;
+
 				case NetworkController::NETCONF_QUERY_ACCESS_DENIED: {
 					Packet outp(peer->address(),RR->identity.address(),Packet::VERB_ERROR);
 					outp.append((unsigned char)Packet::VERB_NETWORK_CONFIG_REQUEST);
@@ -732,12 +712,15 @@ bool IncomingPacket::_doNETWORK_CONFIG_REQUEST(const RuntimeEnvironment *RR,cons
 					outp.armor(peer->key(),true);
 					RR->node->putPacket(_remoteAddress,outp.data(),outp.size());
 				} break;
+
 				case NetworkController::NETCONF_QUERY_INTERNAL_SERVER_ERROR:
 					TRACE("NETWORK_CONFIG_REQUEST failed: internal error: %s",netconf.get("error","(unknown)").c_str());
 					break;
+
 				default:
 					TRACE("NETWORK_CONFIG_REQUEST failed: invalid return value from NetworkController::doNetworkConfigRequest()");
 					break;
+
 			}
 		} else {
 			Packet outp(peer->address(),RR->identity.address(),Packet::VERB_ERROR);