Merge #11363: net: Split socket create/connect

3830b6e net: use CreateSocket for binds (Cory Fields)
df3bcf8 net: pass socket closing responsibility up to caller for outgoing connections (Cory Fields)
9e3b2f5 net: Move IsSelectableSocket check into socket creation (Cory Fields)
1729c29 net: split socket creation out of connection (Cory Fields)

Pull request description:

  Requirement for #11227.

  We'll need to create sockets and perform the actual connect in separate steps, so break them up.

  #11227 adds an RAII wrapper around connection attempts, as a belt-and-suspenders in case a CloseSocket is missed.

Tree-SHA512: de675bb718cc56d68893c303b8057ca062c7431eaa17ae7c4829caed119fa3f15b404d8f52aca22a6bca6e73a26fb79e898b335d090ab015bf6456cf417fc694

1 files changed, 28 insertions, 42 deletions

diff --git a/src/net.cpp b/src/net.cpp
index c0f31e83dd..23bf640472 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -415,39 +415,48 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo
     if (addrConnect.IsValid()) {
         bool proxyConnectionFailed = false;
 
-        if (GetProxy(addrConnect.GetNetwork(), proxy))
+        if (GetProxy(addrConnect.GetNetwork(), proxy)) {
+            hSocket = CreateSocket(proxy.proxy);
+            if (hSocket == INVALID_SOCKET) {
+                return nullptr;
+            }
             connected = ConnectThroughProxy(proxy, addrConnect.ToStringIP(), addrConnect.GetPort(), hSocket, nConnectTimeout, &proxyConnectionFailed);
-        else // no proxy needed (none set for target network)
+        } else {
+            // no proxy needed (none set for target network)
+            hSocket = CreateSocket(addrConnect);
+            if (hSocket == INVALID_SOCKET) {
+                return nullptr;
+            }
             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)) {
+        hSocket = CreateSocket(proxy.proxy);
+        if (hSocket == INVALID_SOCKET) {
+            return nullptr;
+        }
         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();
-        uint64_t nonce = GetDeterministicRandomizer(RANDOMIZER_ID_LOCALHOSTNONCE).Write(id).Finalize();
-        CAddress addr_bind = GetBindAddress(hSocket);
-        CNode* pnode = new CNode(id, nLocalServices, GetBestHeight(), hSocket, addrConnect, CalculateKeyedNetGroup(addrConnect), nonce, addr_bind, pszDest ? pszDest : "", false);
-        pnode->AddRef();
-
-        return pnode;
+    if (!connected) {
+        CloseSocket(hSocket);
+        return nullptr;
     }
 
-    return nullptr;
+    // Add node
+    NodeId id = GetNewNodeId();
+    uint64_t nonce = GetDeterministicRandomizer(RANDOMIZER_ID_LOCALHOSTNONCE).Write(id).Finalize();
+    CAddress addr_bind = GetBindAddress(hSocket);
+    CNode* pnode = new CNode(id, nLocalServices, GetBestHeight(), hSocket, addrConnect, CalculateKeyedNetGroup(addrConnect), nonce, addr_bind, pszDest ? pszDest : "", false);
+    pnode->AddRef();
+
+    return pnode;
 }
 
 void CConnman::DumpBanlist()
@@ -2056,44 +2065,21 @@ bool CConnman::BindListenPort(const CService &addrBind, std::string& strError, b
         return false;
     }
 
-    SOCKET hListenSocket = socket(((struct sockaddr*)&sockaddr)->sa_family, SOCK_STREAM, IPPROTO_TCP);
+    SOCKET hListenSocket = CreateSocket(addrBind);
     if (hListenSocket == INVALID_SOCKET)
     {
         strError = strprintf("Error: Couldn't open socket for incoming connections (socket returned error %s)", NetworkErrorString(WSAGetLastError()));
         LogPrintf("%s\n", strError);
         return false;
     }
-    if (!IsSelectableSocket(hListenSocket))
-    {
-        strError = "Error: Couldn't create a listenable socket for incoming connections";
-        LogPrintf("%s\n", strError);
-        return false;
-    }
-
-
 #ifndef WIN32
-#ifdef SO_NOSIGPIPE
-    // Different way of disabling SIGPIPE on BSD
-    setsockopt(hListenSocket, SOL_SOCKET, SO_NOSIGPIPE, (void*)&nOne, sizeof(int));
-#endif
     // Allow binding if the port is still in TIME_WAIT state after
     // the program was closed and restarted.
     setsockopt(hListenSocket, SOL_SOCKET, SO_REUSEADDR, (void*)&nOne, sizeof(int));
-    // Disable Nagle's algorithm
-    setsockopt(hListenSocket, IPPROTO_TCP, TCP_NODELAY, (void*)&nOne, sizeof(int));
 #else
     setsockopt(hListenSocket, SOL_SOCKET, SO_REUSEADDR, (const char*)&nOne, sizeof(int));
-    setsockopt(hListenSocket, IPPROTO_TCP, TCP_NODELAY, (const char*)&nOne, sizeof(int));
 #endif
 
-    // Set to non-blocking, incoming connections will also inherit this
-    if (!SetSocketNonBlocking(hListenSocket, true)) {
-        CloseSocket(hListenSocket);
-        strError = strprintf("BindListenPort: Setting listening socket to non-blocking failed, error %s\n", NetworkErrorString(WSAGetLastError()));
-        LogPrintf("%s\n", strError);
-        return false;
-    }
-
     // some systems don't have IPV6_V6ONLY but are always v6only; others do have the option
     // and enable it by default or not. Try to enable it, if possible.
     if (addrBind.IsIPv6()) {