fix ipv6 handling between GUI and barriers/barrierc; zero-fill sockaddr_in(6) structs prior to initializing; update --help output

src/gui/src/MainWindow.cpp

@@ -581,7 +581,7 @@ bool MainWindow::clientArgs(QStringList& args, QString& app)
     if (m_pCheckBoxAutoConfig->isChecked()) {
         if (m_pComboServerList->count() != 0) {
             QString serverIp = m_pComboServerList->currentText();
-            args << serverIp + ":" + QString::number(appConfig().port());
+            args << "[" + serverIp + "]:" + QString::number(appConfig().port());
             return true;
         }
     }
@@ -595,7 +595,7 @@ bool MainWindow::clientArgs(QStringList& args, QString& app)
         return false;
     }
 
-    args << m_pLineEditHostname->text() + ":" + QString::number(appConfig().port());
+    args << "[" + m_pLineEditHostname->text() + "]:" + QString::number(appConfig().port());
 
     return true;
 }
@@ -637,8 +637,10 @@ QString MainWindow::configFilename()
 
 QString MainWindow::address()
 {
-    QString i = appConfig().networkInterface();
+    QString address = appConfig().networkInterface();
-    return (!i.isEmpty() ? i : "") + ":" + QString::number(appConfig().port());
+    if (!address.isEmpty())
+        address = "[" + address + "]";
+    return address + ":" + QString::number(appConfig().port());
 }
 
 QString MainWindow::appPath(const QString& name)

src/lib/arch/unix/ArchNetworkBSD.cpp

@@ -113,6 +113,11 @@ ArchNetworkBSD::newSocket(EAddressFamily family, ESocketType type)
     }
     try {
         setBlockingOnSocket(fd, false);
+        if (family == kINET6) {
+            int flag = 0;
+            if (setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &flag, sizeof(flag)) != 0)
+                throwError(errno);
+        }
     }
     catch (...) {
         close(fd);
@@ -647,8 +652,8 @@ ArchNetworkBSD::newAnyAddr(EAddressFamily family)
     switch (family) {
     case kINET: {
         auto* ipAddr = TYPED_ADDR(struct sockaddr_in, addr);
+        memset(ipAddr, 0, sizeof(struct sockaddr_in));
         ipAddr->sin_family         = AF_INET;
-        ipAddr->sin_port           = 0;
         ipAddr->sin_addr.s_addr    = INADDR_ANY;
         addr->m_len                = (socklen_t)sizeof(struct sockaddr_in);
         break;
@@ -656,8 +661,8 @@ ArchNetworkBSD::newAnyAddr(EAddressFamily family)
 
     case kINET6: {
         auto* ipAddr = TYPED_ADDR(struct sockaddr_in6, addr);
+        memset(ipAddr, 0, sizeof(struct sockaddr_in6));
         ipAddr->sin6_family         = AF_INET6;
-        ipAddr->sin6_port           = 0;
         memcpy(&ipAddr->sin6_addr, &in6addr_any, sizeof(in6addr_any));
         addr->m_len                = (socklen_t)sizeof(struct sockaddr_in6);
         break;

src/lib/arch/win32/ArchNetworkWinsock.cpp

@@ -213,9 +213,9 @@ ArchNetworkWinsock::newSocket(EAddressFamily family, ESocketType type)
     }
     try {
         setBlockingOnSocket(fd, false);
-        BOOL flag = 0;
+        if (family == kINET6) {
-        int size     = sizeof(flag);
+            int flag = 0;
-        if (setsockopt_winsock(fd, IPPROTO_IPV6, IPV6_V6ONLY, &flag, size) == SOCKET_ERROR) {
+            if (setsockopt_winsock(fd, IPPROTO_IPV6, IPV6_V6ONLY, &flag, sizeof(flag)) == SOCKET_ERROR)
                 throwError(getsockerror_winsock());
         }
     }
@@ -685,8 +685,8 @@ ArchNetworkWinsock::newAnyAddr(EAddressFamily family)
     case kINET: {
         addr = ArchNetAddressImpl::alloc(sizeof(struct sockaddr_in));
         auto* ipAddr = TYPED_ADDR(struct sockaddr_in, addr);
+        memset(ipAddr, 0, sizeof(struct sockaddr_in));
         ipAddr->sin_family         = AF_INET;
-        ipAddr->sin_port           = 0;
         ipAddr->sin_addr.s_addr    = INADDR_ANY;
         break;
     }
@@ -694,8 +694,8 @@ ArchNetworkWinsock::newAnyAddr(EAddressFamily family)
     case kINET6: {
         addr = ArchNetAddressImpl::alloc(sizeof(struct sockaddr_in6));
         auto* ipAddr = TYPED_ADDR(struct sockaddr_in6, addr);
+        memset(ipAddr, 0, sizeof(struct sockaddr_in6));
         ipAddr->sin6_family         = AF_INET6;
-        ipAddr->sin6_port           = 0;
         memcpy(&ipAddr->sin6_addr, &in6addr_any, sizeof(in6addr_any));
         break;
     }

src/lib/barrier/ClientApp.cpp

@@ -132,8 +132,9 @@ ClientApp::help()
            << "Default options are marked with a *" << std::endl
            << std::endl
            << "The server address is of the form: [<hostname>][:<port>]. The hostname" << std::endl
-           << "must be the address or hostname of the server.  The port overrides the" << std::endl
+           << "must be the address or hostname of the server. Placing brackets around" << std::endl
-           << "default port, " << kDefaultPort << "." << std::endl;
+           << "an IPv6 address is required when also specifying a port number and " << std::endl
+           << "optional otherwise. The default port number is " << kDefaultPort << "." << std::endl;
 
     LOG((CLOG_PRINT "%s", buffer.str().c_str()));
 }

src/lib/barrier/ServerApp.cpp

@@ -139,8 +139,9 @@ ServerApp::help()
            << std::endl
            << "The argument for --address is of the form: [<hostname>][:<port>].  The" << std::endl
            << "hostname must be the address or hostname of an interface on the system." << std::endl
-           << "The default is to listen on all interfaces.  The port overrides the" << std::endl
+           << "Placing brackets around an IPv6 address is required when also specifying " << std::endl
-           << "default port, " << kDefaultPort << "." << std::endl
+           << "a port number and optional otherwise. The default is to listen on all" << std::endl
+           << "interfaces using port number " << kDefaultPort << "." << std::endl
            << std::endl
            << "If no configuration file pathname is provided then the first of the" << std::endl
            << "following to load successfully sets the configuration:" << std::endl
@@ -506,6 +507,16 @@ ServerApp::openServerScreen()
     return screen;
 }
 
+static const char* const family_string(IArchNetwork::EAddressFamily family)
+{
+    if (family == IArchNetwork::kINET)
+        return "IPv4";
+    if (family == IArchNetwork::kINET6)
+        // assume IPv6 sockets are setup to support IPv4 traffic as well
+        return "IPv4/IPv6";
+    return "Unknown";
+}
+
 bool 
 ServerApp::startServer()
 {
@@ -531,13 +542,15 @@ ServerApp::startServer()
     double retryTime;
     ClientListener* listener = NULL;
     try {
-        listener   = openClientListener(args().m_config->getBarrierAddress());
+        auto listenAddress = args().m_config->getBarrierAddress();
+        auto family = family_string(ARCH->getAddrFamily(listenAddress.getAddress()));
+        listener   = openClientListener(listenAddress);
         m_server   = openServer(*args().m_config, m_primaryClient);
         listener->setServer(m_server);
         m_server->setListener(listener);
         m_listener = listener;
         updateStatus();
-        LOG((CLOG_NOTE "started server, waiting for clients"));
+        LOG((CLOG_NOTE "started server (%s), waiting for clients", family));
         m_serverState = kStarted;
         return true;
     }

src/lib/net/NetworkAddress.cpp

@@ -28,6 +28,45 @@
 // NetworkAddress
 //
 
+static bool parse_address(const std::string& address, std::string& host, int& port)
+{
+    /* Three cases ---
+    * brackets:  parse inside for host, check end for port as :INTEGER. DONE
+    * one colon: ipv4 address with port. DONE
+    * otherwise: all host, no port. DONE
+    *
+    * very, very little error checking. depends on address being trimmed before call.
+    *
+    * does not override port with a default value if no port was found in address.
+    */
+
+    if (address[0] == '[') {
+        // bracketed host possibly followed by port as :INTEGER
+        auto endBracket = address.find(']', 1);
+        if (endBracket == std::string::npos)
+            return false;
+        host = address.substr(1, endBracket - 1);
+        if (endBracket + 1 < address.length()) {
+            // port follows (or garbage)
+            if (address[endBracket + 1] != ':')
+                return false;
+            port = std::strtol(&address[endBracket + 2], nullptr, 10);
+        }
+    } else {
+        auto colon = address.find(':');
+        if (colon != std::string::npos && address.find(':', colon + 1) == std::string::npos) {
+            // one single colon, must be ipv4 with port
+            host = address.substr(0, colon);
+            port = std::strtol(&address[colon + 1], nullptr, 10);
+        } else {
+            // no colons (ipv4) or more than one colon (ipv6), both without port
+            host = address;
+        }
+    }
+
+    return true;
+}
+
 // name re-resolution adapted from a patch by Brent Priddy.
 
 NetworkAddress::NetworkAddress() :
@@ -62,50 +101,9 @@ NetworkAddress::NetworkAddress(const String& hostname, int port) :
     m_hostname(hostname),
     m_port(port)
 {
-    // check for port suffix
+    if (!parse_address(hostname, m_hostname, m_port))
-    String::size_type i = m_hostname.rfind(':');
+        throw XSocketAddress(XSocketAddress::kUnknown,
-    if (i != String::npos && i + 1 < m_hostname.size()) {
-        // found a colon.  see if it looks like an IPv6 address.
-        bool colonNotation = false;
-        bool dotNotation   = false;
-        bool doubleColon   = false;
-        for (String::size_type j = 0; j < i; ++j) {
-            if (m_hostname[j] == ':') {
-                colonNotation = true;
-                dotNotation   = false;
-                if (m_hostname[j + 1] == ':') {
-                    doubleColon = true;
-                }
-            }
-            else if (m_hostname[j] == '.' && colonNotation) {
-                dotNotation = true;
-            }
-        }
-
-        // port suffix is ambiguous with IPv6 notation if there's
-        // a double colon and the end of the address is not in dot
-        // notation.  in that case we assume it's not a port suffix.
-        // the user can replace the double colon with zeros to
-        // disambiguate.
-        if ((!doubleColon || dotNotation) && !colonNotation) {
-            // parse port from hostname
-            char* end;
-            const char* chostname = m_hostname.c_str();
-            long suffixPort = strtol(chostname + i + 1, &end, 10);
-            if (end == chostname + i + 1 || *end != '\0') {
-                throw XSocketAddress(XSocketAddress::kBadPort,
             m_hostname, m_port);
-            }
-
-            // trim port from hostname
-            m_hostname.erase(i);
-
-            // save port
-            m_port = static_cast<int>(suffixPort);
-        }
-    }
-
-    // check port number
     checkPort();
 }
 
@@ -145,7 +143,7 @@ NetworkAddress::resolve()
         // if hostname is empty then use wildcard address otherwise look
         // up the name.
         if (m_hostname.empty()) {
-            m_address = ARCH->newAnyAddr(IArchNetwork::kINET);
+            m_address = ARCH->newAnyAddr(IArchNetwork::kINET6);
         }
         else {
             m_address = ARCH->nameToAddr(m_hostname);