diff --git a/src/mesh/DSRRouter.cpp b/src/mesh/DSRRouter.cpp new file mode 100644 index 000000000..00c2a80d3 --- /dev/null +++ b/src/mesh/DSRRouter.cpp @@ -0,0 +1,80 @@ +#include "DSRRouter.h" +#include "configuration.h" + +/* when we receive any packet + +- sniff and update tables (especially useful to find adjacent nodes). Update user, network and position info. +- if we need to route() that packet, resend it to the next_hop based on our nodedb. +- if it is broadcast or destined for our node, deliver locally +- handle routereply/routeerror/routediscovery messages as described below +- then free it + +routeDiscovery + +- if we've already passed through us (or is from us), then it ignore it +- use the nodes already mentioned in the request to update our routing table +- if they were looking for us, send back a routereply +- if max_hops is zero and they weren't looking for us, drop (FIXME, send back error - I think not though?) +- if we receive a discovery packet, we use it to populate next_hop (if needed) towards the requester (after decrementing max_hops) +- if we receive a discovery packet, and we have a next_hop in our nodedb for that destination we send a (reliable) we send a route +reply towards the requester + +when sending any reliable packet + +- if timeout doing retries, send a routeError (nak) message back towards the original requester. all nodes eavesdrop on that +packet and update their route caches. + +when we receive a routereply packet + +- update next_hop on the node, if the new reply needs fewer hops than the existing one (we prefer shorter paths). fixme, someday +use a better heuristic + +when we receive a routeError packet + +- delete the route for that failed recipient, restartRouteDiscovery() +- if we receive routeerror in response to a discovery, +- fixme, eventually keep caches of possible other routes. +*/ + +void DSRRouter::sniffReceived(const MeshPacket *p) +{ + + // FIXME, update nodedb + + // Handle route discovery packets (will be a broadcast message) + if (p->decoded.which_payload == SubPacket_request_tag) { + // FIXME - always start request with the senders nodenum + + if (weAreInRoute(p->decoded.request)) { + DEBUG_MSG("Ignoring a route request that contains us\n"); + } else { + updateRoutes(p->decoded.request, false); // Update our routing tables based on the route that came in so far on this request + + if (p->decoded.dest == getNodeNum()) { + // They were looking for us, send back a route reply (the sender address will be first in the list) + sendRouteReply(p->decoded.request); + } else { + // They were looking for someone else, forward it along (as a zero hop broadcast) + NodeNum nextHop = getNextHop(p->decoded.dest); + if (nextHop) { + // in our route cache, reply to the requester (the sender address will be first in the list) + sendRouteReply(p->decoded.request, nextHop); + } else { + // Not in our route cache, rebroadcast on their behalf (after adding ourselves to the request route) + resendRouteRequest(p); + } + } + } + } + + // Handle regular packets + if (p->to == getNodeNum()) { // Destined for us (at least for this hop) + + // We need to route this packet + if (p->decoded.dest != p->to) { + // FIXME + } + } + + return ReliableRouter::sniffReceived(p); +} \ No newline at end of file diff --git a/src/mesh/DSRRouter.h b/src/mesh/DSRRouter.h new file mode 100644 index 000000000..5ecbdc8e5 --- /dev/null +++ b/src/mesh/DSRRouter.h @@ -0,0 +1,39 @@ +#include "ReliableRouter.h" + +class DSRRouter : public ReliableRouter +{ + + protected: + /** + * Every (non duplicate) packet this node receives will be passed through this method. This allows subclasses to + * update routing tables etc... based on what we overhear (even for messages not destined to our node) + */ + virtual void sniffReceived(const MeshPacket *p); + + private: + /** + * Does our node appear in the specified route + */ + bool weAreInRoute(const RouteDiscovery &route); + + /** + * Given a DSR route, use that route to update our DB of possible routes + **/ + void updateRoutes(const RouteDiscovery &route, bool reverse); + + /** + * send back a route reply (the sender address will be first in the list) + */ + void sendRouteReply(const RouteDiscovery &route, NodeNum toAppend = 0); + + /** + * Given a nodenum return the next node we should forward to if we want to reach that node. + * + * @return 0 if no route found + */ + NodeNum getNextHop(NodeNum dest); + + /** Not in our route cache, rebroadcast on their behalf (after adding ourselves to the request route) + */ + void resendRouteRequest(const MeshPacket *p); +}; \ No newline at end of file diff --git a/src/mesh/Router.cpp b/src/mesh/Router.cpp index a7d570781..428f19fee 100644 --- a/src/mesh/Router.cpp +++ b/src/mesh/Router.cpp @@ -90,6 +90,10 @@ ErrorCode Router::send(MeshPacket *p) packetPool.release(p); return ERRNO_OK; } else { + // Never set the want_ack flag on broadcast packets sent over the air. + if (p->to == NODENUM_BROADCAST) + p->want_ack = false; + // If the packet hasn't yet been encrypted, do so now (it might already be encrypted if we are just forwarding it) assert(p->which_payload == MeshPacket_encrypted_tag || @@ -125,9 +129,10 @@ ErrorCode Router::send(MeshPacket *p) * Every (non duplicate) packet this node receives will be passed through this method. This allows subclasses to * update routing tables etc... based on what we overhear (even for messages not destined to our node) */ -void Router::sniffReceived(MeshPacket *p) +void Router::sniffReceived(const MeshPacket *p) { - DEBUG_MSG("Sniffing packet not sent to us fr=0x%x,to=0x%x,id=%d\n", p->from, p->to, p->id); + DEBUG_MSG("FIXME-update-db Sniffing packet fr=0x%x,to=0x%x,id=%d\n", p->from, p->to, p->id); + } bool Router::perhapsDecode(MeshPacket *p) diff --git a/src/mesh/Router.h b/src/mesh/Router.h index d0a8e029c..0f06ce3e9 100644 --- a/src/mesh/Router.h +++ b/src/mesh/Router.h @@ -75,7 +75,7 @@ class Router * Every (non duplicate) packet this node receives will be passed through this method. This allows subclasses to * update routing tables etc... based on what we overhear (even for messages not destined to our node) */ - virtual void sniffReceived(MeshPacket *p); + virtual void sniffReceived(const MeshPacket *p); /** * Remove any encryption and decode the protobufs inside this packet (if necessary).