Bug#627139: mumble-server: murmurd doesn't include remote IP in password failure log message - needed for fail2ban

[Iain Georgeson]

Package: mumble-server
Version: 1.2.2-6
Severity: minor
Tags: patch

I like to use fail2ban to monitor any network service with login capability.
I'm using an external authenticator to make murmurd auth against LDAP,
so I want to be sure I'm not allowing an avenue for dictionary attacks
against it.

fail2ban needs to match a single log line which contains:
 * a date
 * an IP
 * some string which shows it's a login failure (e.g. /Wrong password for user/)

murmurd doesn't include the IP in that log message so fail2ban can't get
the information it needs. Did this to it:


--- src/murmur/Messages.cpp.orig	2011-05-17 23:31:54.000000000 +0100
+++ src/murmur/Messages.cpp	2011-05-17 22:27:41.000000000 +0100
@@ -172,7 +172,9 @@
 	}
 
 	if (! ok) {
-		log(uSource, QString("Rejected connection: %1").arg(reason));
+	    log(uSource, QString("Rejected connection from %1: %2").
+		    arg(addressToString(uSource->peerAddress(),
+				        uSource->peerPort()), reason));
 		MumbleProto::Reject mpr;
 		mpr.set_reason(u8(reason));
 		mpr.set_type(rtType);


My fail2ban setup now looks like

jail.local:
[mumble-server]

enabled = true
port    = 64738
filter  = mumble-server
logpath = /var/log/mumble-server/mumble-server.log


filter.d/mumble-server.conf:
failregex = ^\<W\>.*Rejected connection from <HOST>:\d+: Wrong password for user$


-- System Information:
Debian Release: 6.0.1
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: i386 (i686)

Kernel: Linux 2.6.38.3-linode32 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages mumble-server depends on:
ii  adduser                3.112+nmu2        add and remove users and groups
ii  dbus                   1.2.24-4          simple interprocess messaging syst
ii  debconf [debconf-2.0]  1.5.36.1          Debian configuration management sy
ii  libavahi-client3       0.6.27-2+squeeze1 Avahi client library
ii  libavahi-common3       0.6.27-2+squeeze1 Avahi common library
ii  libavahi-compat-libdns 0.6.27-2+squeeze1 Avahi Apple Bonjour compatibility 
ii  libc6                  2.11.2-10         Embedded GNU C Library: Shared lib
ii  libcap2                1:2.19-3          support for getting/setting POSIX.
ii  libgcc1                1:4.4.5-8         GCC support library
ii  libiceutil33           3.3.1-12          Ice for C++ misc utility library
ii  libprotobuf6           2.3.0-4           protocol buffers C++ library
ii  libqt4-dbus            4:4.6.3-4         Qt 4 D-Bus module
ii  libqt4-network         4:4.6.3-4         Qt 4 network module
ii  libqt4-sql             4:4.6.3-4         Qt 4 SQL module
ii  libqt4-sql-sqlite      4:4.6.3-4         Qt 4 SQLite 3 database driver
ii  libqt4-xml             4:4.6.3-4         Qt 4 XML module
ii  libqtcore4             4:4.6.3-4         Qt 4 core module
ii  libssl0.9.8            0.9.8o-4squeeze1  SSL shared libraries
ii  libstdc++6             4.4.5-8           The GNU Standard C++ Library v3
ii  libzeroc-ice33         3.3.1-12          Ice for C++ runtime library

mumble-server recommends no packages.

Versions of packages mumble-server suggests:
pn  mumble-django                 <none>     (no description available)
pn  mumble-server-web             <none>     (no description available)

-- Configuration Files:
/etc/init.d/mumble-server changed [not included]
/etc/mumble-server.ini [Errno 13] Permission denied: u'/etc/mumble-server.ini'

-- debconf information excluded