From 08b6d78bb3f8aae7f22659ff255251594db6f7ed Mon Sep 17 00:00:00 2001
From: Janne Koschinski <janne@kuschku.de>
Date: Tue, 12 Feb 2019 22:30:45 +0100
Subject: [PATCH] Allow configuring listen address

---
 src/common/main.cpp      |  1 +
 src/core/identserver.cpp | 74 ++++++++++++++++++++++++++++++----------
 2 files changed, 57 insertions(+), 18 deletions(-)

diff --git a/src/common/main.cpp b/src/common/main.cpp
index cc1bbfe7..766094c3 100644
--- a/src/common/main.cpp
+++ b/src/common/main.cpp
@@ -197,6 +197,7 @@ int main(int argc, char **argv)
     cliParser->addSwitch("strict-ident", 0, "Use users' quasselcore username as ident reply. Ignores each user's configured ident setting.");
     cliParser->addSwitch("ident-daemon", 0, "Enable internal ident daemon");
     cliParser->addOption("ident-port", 0, "The port quasselcore will listen at for ident requests. Only meaningful with --ident-daemon", "port", "10113");
+    cliParser->addOption("ident-listen", 0, "The address(es) quasselcore will listen on for ident requests", "<address>[,<address>[,...]]", "::1,127.0.0.1");
 #ifdef HAVE_SSL
     cliParser->addSwitch("require-ssl", 0, "Require SSL for remote (non-loopback) client connections");
     cliParser->addOption("ssl-cert", 0, "Specify the path to the SSL Certificate", "path", "configdir/quasselCert.pem");
diff --git a/src/core/identserver.cpp b/src/core/identserver.cpp
index 1d634d80..510430a7 100644
--- a/src/core/identserver.cpp
+++ b/src/core/identserver.cpp
@@ -34,27 +34,65 @@ IdentServer::IdentServer(QObject *parent)
 
 bool IdentServer::startListening()
 {
-    uint16_t port = Quassel::optionValue("ident-port").toUShort();
-
     bool success = false;
-    if (_v6server.listen(QHostAddress("::"), port)) {
-        quInfo() << qPrintable(
-                tr("Listening for identd clients on IPv6 %1 port %2")
-                        .arg("::")
-                        .arg(_v6server.serverPort())
-        );
-
-        success = true;
-    }
 
-    if (_server.listen(QHostAddress("0.0.0.0"), port)) {
-        quInfo() << qPrintable(
-                tr("Listening for identd clients on IPv4 %1 port %2")
-                        .arg("0.0.0.0")
-                        .arg(_server.serverPort())
-        );
+    uint16_t port = Quassel::optionValue("ident-port").toUShort();
 
-        success = true;
+    const QString listen = Quassel::optionValue("ident-listen");
+    const QStringList listen_list = listen.split(",", QString::SkipEmptyParts);
+    for (const QString &listen_term : listen_list) { // TODO: handle multiple interfaces for same TCP version gracefully
+        QHostAddress addr;
+        if (!addr.setAddress(listen_term)) {
+            qCritical() << qPrintable(
+                    tr("Invalid listen address %1")
+                            .arg(listen_term)
+            );
+        }
+        else {
+            switch (addr.protocol()) {
+                case QAbstractSocket::IPv6Protocol:
+                    if (_v6server.listen(addr, port)) {
+                        quInfo() << qPrintable(
+                                tr("Listening for identd requests on IPv6 %1 port %2")
+                                        .arg(addr.toString())
+                                        .arg(_v6server.serverPort())
+                        );
+                        success = true;
+                    }
+                    else
+                        quWarning() << qPrintable(
+                                tr("Could not open IPv6 interface %1:%2: %3")
+                                        .arg(addr.toString())
+                                        .arg(port)
+                                        .arg(_v6server.errorString()));
+                    break;
+                case QAbstractSocket::IPv4Protocol:
+                    if (_server.listen(addr, port)) {
+                        quInfo() << qPrintable(
+                                tr("Listening for identd requests on IPv4 %1 port %2")
+                                        .arg(addr.toString())
+                                        .arg(_server.serverPort())
+                        );
+                        success = true;
+                    }
+                    else {
+                        // if v6 succeeded on Any, the port will be already in use - don't display the error then
+                        if (!success || _server.serverError() != QAbstractSocket::AddressInUseError)
+                            quWarning() << qPrintable(
+                                    tr("Could not open IPv4 interface %1:%2: %3")
+                                            .arg(addr.toString())
+                                            .arg(port)
+                                            .arg(_server.errorString()));
+                    }
+                    break;
+                default:
+                    qCritical() << qPrintable(
+                            tr("Invalid listen address %1, unknown network protocol")
+                                    .arg(listen_term)
+                    );
+                    break;
+            }
+        }
     }
 
     if (!success) {
-- 
2.20.1