net: separate resolving and conecting

ConnectSocketByName handled resolves as necessary, obscuring the connection
process. With them separated, each can be handled asynchronously.

Also, since proxies must be considered now anyway, go ahead and eliminate the
ConnectSocket wrapper and use ConnectSocketDirectly... directly.

1 files changed, 39 insertions, 19 deletions

diff --git a/src/net.cpp b/src/net.cpp
index 587c9e5110..a9f26fb566 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -380,19 +380,16 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo
         pszDest ? pszDest : addrConnect.ToString(),
         pszDest ? 0.0 : (double)(GetAdjustedTime() - addrConnect.nTime)/3600.0);
 
-    // Connect
-    SOCKET hSocket;
-    bool proxyConnectionFailed = false;
-    if (pszDest ? ConnectSocketByName(addrConnect, hSocket, pszDest, Params().GetDefaultPort(), nConnectTimeout, &proxyConnectionFailed) :
-                  ConnectSocket(addrConnect, hSocket, nConnectTimeout, &proxyConnectionFailed))
-    {
-        if (!IsSelectableSocket(hSocket)) {
-            LogPrintf("Cannot create connection: non-selectable socket created (fd >= FD_SETSIZE ?)\n");
-            CloseSocket(hSocket);
-            return nullptr;
-        }
-
-        if (pszDest && addrConnect.IsValid()) {
+    // Resolve
+    const int default_port = Params().GetDefaultPort();
+    if (pszDest) {
+        std::vector<CService> resolved;
+        if (Lookup(pszDest, resolved,  default_port, fNameLookup && !HaveNameProxy(), 256) && !resolved.empty()) {
+            addrConnect = CAddress(resolved[GetRand(resolved.size())], NODE_NONE);
+            if (!addrConnect.IsValid()) {
+                LogPrint(BCLog::NET, "Resolver returned invalid address %s for %s", addrConnect.ToString(), pszDest);
+                return nullptr;
+            }
             // It is possible that we already have a connection to the IP/port pszDest resolved to.
             // In that case, drop the connection that was just created, and return the existing CNode instead.
             // Also store the name we used to connect in that CNode, so that future FindNode() calls to that
@@ -402,13 +399,40 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo
             if (pnode)
             {
                 pnode->MaybeSetAddrName(std::string(pszDest));
-                CloseSocket(hSocket);
                 LogPrintf("Failed to open new connection, already connected\n");
                 return nullptr;
             }
         }
+    }
 
-        addrman.Attempt(addrConnect, fCountFailure);
+    // Connect
+    bool connected = false;
+    SOCKET hSocket;
+    proxyType proxy;
+    if (addrConnect.IsValid()) {
+        bool proxyConnectionFailed = false;
+
+        if (GetProxy(addrConnect.GetNetwork(), proxy))
+            connected = ConnectThroughProxy(proxy, addrConnect.ToStringIP(), addrConnect.GetPort(), hSocket, nConnectTimeout, &proxyConnectionFailed);
+        else // no proxy needed (none set for target network)
+            connected = ConnectSocketDirectly(addrConnect, hSocket, nConnectTimeout);
+        if (!proxyConnectionFailed) {
+            // If a connection to the node was attempted, and failure (if any) is not caused by a problem connecting to
+            // the proxy, mark this as an attempt.
+            addrman.Attempt(addrConnect, fCountFailure);
+        }
+    } else if (pszDest && GetNameProxy(proxy)) {
+        std::string host;
+        int port = default_port;
+        SplitHostPort(std::string(pszDest), port, host);
+        connected = ConnectThroughProxy(proxy, host, port, hSocket, nConnectTimeout, nullptr);
+    }
+    if (connected) {
+        if (!IsSelectableSocket(hSocket)) {
+            LogPrintf("Cannot create connection: non-selectable socket created (fd >= FD_SETSIZE ?)\n");
+            CloseSocket(hSocket);
+            return nullptr;
+        }
 
         // Add node
         NodeId id = GetNewNodeId();
@@ -419,10 +443,6 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo
         pnode->AddRef();
 
         return pnode;
-    } else if (!proxyConnectionFailed) {
-        // If connecting to the node failed, and failure is not caused by a problem connecting to
-        // the proxy, mark this as an attempt.
-        addrman.Attempt(addrConnect, fCountFailure);
     }
 
     return nullptr;