delay dns resolution for snode until we have a session with it

llarp/ev/ev.hpp

@@ -560,7 +560,7 @@ namespace llarp
     {
       sockaddr_storage st;
       socklen_t sl;
-      if (getpeername(fd, (sockaddr*)&st, &sl) == 0)
+      if(getpeername(fd, (sockaddr*)&st, &sl) == 0)
       {
         // we are connected yeh boi
         if(_conn)

llarp/ev/ev_epoll.cpp

@@ -322,7 +322,7 @@ llarp_epoll_loop::tick(int ms)
 {
   epoll_event events[1024];
   int result;
-  result = epoll_wait(epollfd, events, 1024, ms);
+  result     = epoll_wait(epollfd, events, 1024, ms);
   bool didIO = false;
   if(result > 0)
   {
@@ -339,7 +339,7 @@ llarp_epoll_loop::tick(int ms)
           llarp::LogDebug("epoll error");
           ev->error();
         }
-        else 
+        else
         {
           // write THEN READ don't revert me
           if(events[idx].events & EPOLLOUT)

llarp/exit/session.cpp

@@ -101,19 +101,34 @@ namespace llarp
         llarp::LogError("failed to send exit request");
     }
 
+    void
+    BaseSession::AddReadyHook(SessionReadyFunc func)
+    {
+      m_PendingCallbacks.emplace_back(func);
+    }
+
     bool
     BaseSession::HandleGotExit(llarp::path::Path* p, llarp_time_t b)
     {
-      m_LastUse = router->Now();
+      BaseSession* self = this;
+      m_LastUse         = router->Now();
       if(b == 0)
         llarp::LogInfo("obtained an exit via ", p->Endpoint());
+      else
+        self = nullptr;
 
+      for(auto& f : m_PendingCallbacks)
+        f(self);
+      m_PendingCallbacks.clear();
       return true;
     }
 
     bool
     BaseSession::Stop()
     {
+      for(auto& f : m_PendingCallbacks)
+        f(nullptr);
+      m_PendingCallbacks.clear();
       auto sendExitClose = [&](llarp::path::Path* p) {
         if(p->SupportsAnyRoles(llarp::path::ePathRoleExit))
         {

llarp/exit/session.hpp

@@ -13,6 +13,10 @@ namespace llarp
 {
   namespace exit
   {
+    struct BaseSession;
+
+    using SessionReadyFunc = std::function< void(BaseSession*) >;
+
     /// a persisting exit session with an exit router
     struct BaseSession : public llarp::path::Builder
     {
@@ -64,6 +68,9 @@ namespace llarp
       bool
       LoadIdentityFromFile(const char* fname);
 
+      void
+      AddReadyHook(SessionReadyFunc func);
+
      protected:
       llarp::RouterID m_ExitRouter;
       llarp::SecretKey m_ExitIdentity;
@@ -107,6 +114,8 @@ namespace llarp
 
       uint64_t m_Counter;
       llarp_time_t m_LastUse;
+
+      std::vector< SessionReadyFunc > m_PendingCallbacks;
     };
 
     struct ExitSession final : public BaseSession

llarp/handlers/tun.cpp

@@ -333,24 +333,28 @@ namespace llarp
           else
           {
             dns::Message *replyMsg = new dns::Message(std::move(msg));
-            service::Endpoint::PathEnsureHook hook = std::bind(
-                &TunEndpoint::SendDNSReply, this, std::placeholders::_1,
-                std::placeholders::_2, replyMsg, reply);
-            return EnsurePathToService(addr, hook, 2000);
+            return EnsurePathToService(
+                addr,
+                [=](const service::Address &remote, OutboundContext *ctx) {
+                  SendDNSReply(remote, ctx, replyMsg, reply, false);
+                },
+                2000);
           }
         }
         else if(addr.FromString(qname, ".snode"))
         {
-          // TODO: add hook to EnsurePathToSNode
-          EnsurePathToSNode(addr.as_array());
-          huint32_t ip = ObtainIPForAddr(addr, true);
-          if(ip.h)
-            msg.AddINReply(ip);
-          else
+          if(HasPathToSNode(addr.as_array()))
           {
-            llarp::LogWarn("no ip found for ", addr);
-            msg.AddNXReply();
+            msg.AddINReply(ObtainIPForAddr(addr, true));
+            reply(msg);
+            return true;
           }
+          dns::Message *replyMsg = new dns::Message(std::move(msg));
+          EnsurePathToSNode(addr.as_array(),
+                            [=](const RouterID &remote, exit::BaseSession *s) {
+                              SendDNSReply(remote, s, replyMsg, reply, true);
+                            });
+          return true;
         }
         else
           // forward dns
@@ -430,24 +434,6 @@ namespace llarp
       return false;
     }
 
-    void
-    TunEndpoint::SendDNSReply(service::Address addr,
-                              service::Endpoint::OutboundContext *ctx,
-                              dns::Message *request,
-                              std::function< void(dns::Message) > reply)
-    {
-      if(ctx)
-      {
-        huint32_t ip = ObtainIPForAddr(addr, false);
-        request->AddINReply(ip);
-      }
-      else
-        request->AddNXReply();
-
-      reply(*request);
-      delete request;
-    }
-
     bool
     TunEndpoint::MapAddress(const service::Address &addr, huint32_t ip,
                             bool SNode)

llarp/handlers/tun.hpp

@@ -192,10 +192,21 @@ namespace llarp
             });
       }
 
+      template < typename Addr_t, typename Endpoint_t >
       void
-      SendDNSReply(service::Address addr,
-                   service::Endpoint::OutboundContext* ctx, dns::Message* query,
-                   std::function< void(dns::Message) > reply);
+      SendDNSReply(Addr_t addr, Endpoint_t* ctx, dns::Message* query,
+                   std::function< void(dns::Message) > reply, bool snode)
+      {
+        if(ctx)
+        {
+          huint32_t ip = ObtainIPForAddr(addr, snode);
+          query->AddINReply(ip);
+        }
+        else
+          query->AddNXReply();
+        reply(*query);
+        delete query;
+      }
 
 #ifndef WIN32
       /// handles fd injection force android

llarp/router/router.cpp

@@ -193,7 +193,7 @@ namespace llarp
   }
 
   bool
-  Router::OnSessionEstablished(ILinkSession * s)
+  Router::OnSessionEstablished(ILinkSession *s)
   {
     return async_verify_RC(s->GetRemoteRC());
   }
@@ -1228,7 +1228,6 @@ namespace llarp
   bool
   Router::async_verify_RC(const RouterContact &rc)
   {
-    
     if(rc.IsPublicRouter() && whitelistRouters && IsServiceNode())
     {
       if(lokinetRouters.find(rc.pubkey) == lokinetRouters.end())

llarp/router_contact.hpp

@@ -130,9 +130,9 @@ namespace llarp
           && nickname == other.nickname && last_updated == other.last_updated
           && netID == other.netID;
     }
-    
-    bool 
-    operator!=(const RouterContact & other) const 
+
+    bool
+    operator!=(const RouterContact &other) const
     {
       return !(*this == other);
     }

llarp/service/endpoint.cpp

@@ -1205,7 +1205,7 @@ namespace llarp
     }
 
     void
-    Endpoint::EnsurePathToSNode(const RouterID& snode)
+    Endpoint::EnsurePathToSNode(const RouterID& snode, SNodeEnsureHook h)
     {
       if(m_SNodeSessions.count(snode) == 0)
       {
@@ -1219,6 +1219,13 @@ namespace llarp
                           [themIP]() -> huint32_t { return themIP; }),
                 m_Router, 2, numHops));
       }
+      auto range = m_SNodeSessions.equal_range(snode);
+      auto itr   = range.first;
+      while(itr != range.second)
+      {
+        itr->second->AddReadyHook(std::bind(h, snode, std::placeholders::_1));
+        ++itr;
+      }
     }
 
     bool

llarp/service/endpoint.hpp

@@ -366,7 +366,7 @@ namespace llarp
 
       /// ensure a path to a service node by public key
       void
-      EnsurePathToSNode(const RouterID& remote);
+      EnsurePathToSNode(const RouterID& remote, SNodeEnsureHook h);
 
       bool
       HasPathToSNode(const RouterID& remote) const;