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diff --git a/ulogd/doc/ulogd.html b/ulogd/doc/ulogd.html deleted file mode 100644 index 8bf7fed..0000000 --- a/ulogd/doc/ulogd.html +++ /dev/null @@ -1,421 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> -<HTML> -<HEAD> - <META NAME="GENERATOR" CONTENT="LinuxDoc-Tools 0.9.21"> - <TITLE>ULOGD - the Userspace Logging Daemon</TITLE> -</HEAD> -<BODY> -<H1>ULOGD - the Userspace Logging Daemon</H1> - -<H2>Harald Welte <laforge@gnumonks.org></H2>Revision $Revision: 803 $, $Date: 2005-04-18 16:21:17 +0200 (Mon, 18 Apr 2005) $ -<HR> -<EM>This is the documentation for <CODE>ulogd</CODE>, the Userspace logging daemon. -ulogd makes use of the Linux >= 2.4.x packet filter subsystem (iptables) and -the ULOG target for iptables.</EM> -<HR> -<H2><A NAME="s1">1. DESIGN</A></H2> - -<H2><A NAME="ss1.1">1.1 CONCEPT</A> -</H2> - -<P>I want to provide a flexible, almost universal logging daemon for my netfilter -ULOG target. It is not optimized in any way, the goal is to keep as simple as -possible. These are my thoughts about how the architecture which is most -capable of doing that:</P> -<P> -<DL> -<DT><B>Interpreter lugins</B><DD><P>It should be possible to add plugins / runtime modules for new protocols, etc. -For example the standard logging daemon provides source-ip, dest-ip, -source-port, dest-port, etc. Logging for variuos other protocols (GRE, -IPsec, ...) may be implemented as modules.</P> - -<DT><B>Output plugins</B><DD><P>... describe how and where to put the information gained by logging plugins. -The easiest way is to build a line per packet and fprint it to a file. -Some people might want to log into a SQL database or want an output -conforming to the intrusion detection systems communication draft from the -IETF.</P> - -</DL> -</P> - -<H2><A NAME="ss1.2">1.2 DETAILS</A> -</H2> - -<P>The major clue is providing a framework which is as flexible as possible. -Nobody knows what strange network protocols are out there :) Flexibility -depends on the communication between the output of the logging plugins -and input of the output plugins.</P> -<P>Rusty advised me to use some kind of type-key-value triples, which is in fact -what I implemented.</P> -<P>One issue is, of course, performance. Up to ulogd 0.3, ulogd did several -linked list iterations and about 30 malloc() calls _per packet_. This -changed with the new >= 0.9 revisions: -<UL> -<LI>Not a single dynamic allocation in the core during runtime. -Everything is pre-allocated at start of ulogd to provide the highest -possible throughput.</LI> -<LI>Hash tables in addition to the linked lists. Linked lists are only -traversed if we really want to access each element of the list.</LI> -</UL> -</P> - -<H2><A NAME="s2">2. INSTALLATION</A></H2> - - -<H2><A NAME="ss2.1">2.1 Linux kernel</A> -</H2> - -<P>First you will need a recent 2.4.x kernel. If you have a kernel >= -2.4.18-pre8, it already has the kernel suport for ULOG (ipt_ULOG.o).</P> -<P>If you have an older kernel version (between 2.4.0 and 2.4.18-pre6), you -can use the patch-o-matic system of netfilter/iptables, as described in -the following section.</P> - -<H2><A NAME="ss2.2">2.2 ipt_ULOG from netfilter/iptables patch-o-matic</A> -</H2> - -<P>You only need to read this chapter if you have a 2.4.x kernel <= -2.4.18-pre6.</P> -<P>In order to put the ipt_ULOG module into your kernel source,you need the latest -iptables package, or even better: the latest CVS snapshot. A description how to -obtain this is provided on the netfilter -homepage -<A HREF="http://www.netfilter.org/">http://www.netfilter.org/</A>.</P> -<P>To run patch-o-matic, just type -<BLOCKQUOTE><CODE> -<PRE> -make patch-o-matic -</PRE> -</CODE></BLOCKQUOTE> - -in the userspace directory of netfilter CVS.</P> - -<H2><A NAME="ss2.3">2.3 ulogd</A> -</H2> - -<H3>Recompiling the source</H3> - -<P>Download the ulogd package from -<A HREF="http://ftp.netfilter.org/pub/ulogd/">http://ftp.netfilter.org/pub/ulogd/</A> and -untar it. </P> -<P>If you want to build ulogd with MySQL support, type './configure --with-mysql'. You may also have to specify the path of the mysql libraries using '--with-mysql=path'. To build ulogd without MySQL support, just use './configure'.</P> -<P>To compile and install the program, call 'make install'.</P> - -<H3>Using a precompiled package</H3> - -<P>I also provide a SRPM, which should compile on almost any rpm-based distribution. It is available at -<A HREF="http://ftp.netfilter.org/pub/ulogd/">http://ftp.netfilter.org/pub/ulogd/</A></P> -<P>Just download the package and do the usual 'rpm --rebuild <file>'.</P> - -<H2><A NAME="s3">3. Configuration</A></H2> - -<H2><A NAME="ss3.1">3.1 iptables ULOG target</A> -</H2> - -<H3>Quick Setup</H3> - -<P>Just add rules using the ULOG target to your firewalling chain. A very basic -example: -<BLOCKQUOTE><CODE> -<PRE> -iptables -A FORWARD -j ULOG --ulog-nlgroup 32 --ulog-prefix foo -</PRE> -</CODE></BLOCKQUOTE> -</P> -<P>To increase logging performance, try to use the -<BLOCKQUOTE><CODE> -<PRE> ---ulog-qthreshold N -</PRE> -</CODE></BLOCKQUOTE> - -option (where 1 < N <= 50). The number you specify is the amout of packets -batched together in one multipart netlink message. If you set this to 20, the -kernel schedules ulogd only once every 20 packets. All 20 packets are then -processed by ulogd. This reduces the number of context switches between kernel -and userspace.</P> -<P>Of course you can combine the ULOG target with the different netfilter match -modules. For a more detailed description, have a look at the netfilter -HOWTO's, available on the netfilter homepage.</P> -<H3>ULOG target reference</H3> - -<P> -<DL> -<DT><B>--ulog-nlgroup N</B><DD><P>The number of the netlink multicast group to which ULOG'ed packets are sent. -You will have to use the same group number in the ULOG target and ulogd in -order to make logging work.</P> -<DT><B>--ulog-cprange N</B><DD><P>Copyrange. This works like the 'snaplen' paramter of tcpdump. You can specify -a number of bytes up to which the packet is copied. If you say '40', you will -receive the first fourty bytes of every packet. Leave it to '0'</P> -<DT><B>--ulog-qthreshold N</B><DD><P>Queue threshold. If a packet is matched by the iptables rule, and already N -packets are in the queue, the queue is flushed to userspace. You can use this -to implement a policy like: Use a big queue in order to gain high performance, -but still have certain packets logged immediately to userspace.</P> -<DT><B>--ulog-prefix STRING</B><DD><P>A string that is associated with every packet logged by this rule. You can use -this option to later tell from which rule the packet was logged.</P> -</DL> -</P> - -<H3>ipt_ULOG module parameters</H3> - -<P>The ipt_ULOG kernel module has a couple of module loadtime parameters which can -(and should) be tuned to accomodate the needs of the application: -<DL> -<DT><B>nlbufsiz N</B><DD><P>Netlink buffer size. A buffer of the specified size N is allocated for every -netlink group that is used. Please note that due to restrictions of the kernel -memory allocator, we cannot have a buffer size > 128kBytes. Larger buffer -sizes increase the performance, since less kernel/userspace context switches -are needed for the same amount of packets. The backside of this performance -gain is a potentially larger delay. The default value is 4096 bytes, which is -quite small.</P> -<DT><B>flushtimeout N</B><DD><P>The flushtimeout determines, after how many clock ticks (on alpha: 1ms, on -x86 and most other platforms: 10ms time units) the buffer/queue is to be -flushed, even if it is not full. This can be used to have the advantage of a -large buffer, but still a finite maximum delay introduced. The default value -is set to 10 seconds.</P> -</DL> - -Example: -<BLOCKQUOTE><CODE> -<PRE> -modprobe ipt_ULOG nlbufsiz=65535 flushtimeout=100 -</PRE> -</CODE></BLOCKQUOTE> - -This would use a buffer size of 64k and a flushtimeout of 100 clockticks (1 second on x86).</P> - -<H2><A NAME="ss3.2">3.2 ulogd</A> -</H2> - -<P>ulogd is what this is all about, so let's describe it's configuration...</P> -<H3>ulogd configfile syntax reference</H3> - -<P>All configurable parameters of ulogd are in the configfile, typically located -at '/etc/ulogd.conf'.</P> -<P>The following configuration parameters are available: -<DL> -<DT><B>nlgroup</B><DD><P>The netlink multicast group, which ulgogd should bind to. This is the same as -given with the '--ulog-nlgroup' option to iptables.</P> -<DT><B>logfile</B><DD><P>The main logfile, where ulogd reports any errors, warnings and other unexpected conditions. Apart from a regular filename, the following special values can be used; ``syslog'' to log via the unix syslog(3) mechanism. ``stdout'' to log to stdout.</P> -<DT><B>loglevel</B><DD><P>This specifies, how verbose the logging to logfile is. Currently defined -loglevels are: 1=debug information, 3=informational messages, 5=noticable -exceptional conditions, 7=error conditions, 8=fatal errors, program abort.</P> -<DT><B>plugin</B><DD><P>This option is followed by a filename of a ulogd plugin, which ulogd shold load -upon initialization. This option may appear more than once.</P> -<DT><B>rmem</B><DD><P>Size of the netlink socket receive memory. You should set this to at least the -size of the kernel buffer (nlbufsiz parameter of the ipt_ULOG module). Please -note that there is a maximum limit in /proc/sys/net/core/rmem_max which you -cannot exceed by increasing the ``rmem'' parameter. You may need to raise the -system-wide maximum limit before.</P> -<DT><B>bufsize</B><DD><P>Size of the receive buffer. You should set this to at least the socket receive buffer (rmem).</P> -</DL> -</P> -<H3>ulogd commandline option reference</H3> - -<P>Apart from the configfile, there are a couple of commandline options to ulogd: -<DL> -<DT><B>-h --help</B><DD><P>Print a help message about the commandline options.</P> -<DT><B>-V --version</B><DD><P>Print version information about ulogd.</P> -<DT><B>-d --daemon</B><DD><P>For off into daemon mode. Unless you are debugging, you will want to use this -most of the time.</P> -<DT><B>-c --configfile</B><DD><P>Using this commandline option, an alternate config file can be used. This is -important if multiple instances of ulogd are to be run on a single machine.</P> -</DL> -</P> - -<H2><A NAME="s4">4. Available plugins</A></H2> - -<P>It is important to understand that ulogd without plugins does nothing. It will receive packets, and do nothing with them.</P> -<P>There are two kinds of plugins, interpreter and output plugins. Interpreter -plugins parse the packet, output plugin write the interpreted information to -some logfile/database/...</P> - -<H2><A NAME="ss4.1">4.1 Interpreter plugins</A> -</H2> - -<P>ulogd comes with the following interpreter plugins:</P> -<H3>ulogd_BASE.so</H3> - -<P>Basic interpreter plugin for nfmark, timestamp, mac address, ip header, tcp -header, udp header, icmp header, ah/esp header... Most people will want to load -this very important plugin.</P> -<H3>ulogd_PWSNIFF.so</H3> - -<P>Example interpreter plugin to log plaintext passwords as used with FTP and -POP3. Don't blame me for writing this plugin! The protocols are inherently -insecure, and there are a lot of other tools for sniffing passwords... it's -just an example.</P> -<H3>ulogd_LOCAL.so</H3> - -<P>This is a 'virtual interpreter'. It doesn't really return any information on -the packet itself, rather the local system time and hostname. Please note that -the time is the time at the time of logging, not the packets receive time.</P> - -<H2><A NAME="ss4.2">4.2 Output plugins</A> -</H2> - -<P>ulogd comes with the following output plugins:</P> - -<H3>ulogd_OPRINT.so</H3> - -<P>A very simple output module, dumping all packets in the format -<BLOCKQUOTE><CODE> -<PRE> -===>PACKET BOUNDARY -key=value -key=value -... -===>PACKET BOUNDARY -... -</PRE> -</CODE></BLOCKQUOTE> - -to a file. The only useful application is debugging.</P> -<P>The module defines the following configuration directives: -<DL> -<DT><B>dumpfile</B><DD><P>The filename where it should log to. The default is -<CODE>/var/log/ulogd.pktlog</CODE></P> -</DL> -</P> - -<H3>ulogd_LOGEMU.so</H3> - -<P>An output module which tries to emulate the old syslog-based LOG targed as far -as possible. Logging is done to a seperate textfile instead of syslog, though.</P> -<P>The module defines the following configuration directives: -<DL> -<DT><B>file</B><DD><P>The filename where it should log to. The default is -<CODE>/var/log/ulogd.syslogemu</CODE></P> -<DT><B>sync</B><DD><P>Set this to 1 if you want to have your logfile written -synchronously. This may reduce performance, but makes your log-lines appear -immediately. The default is <CODE>0</CODE></P> -</DL> -</P> - -<H3>ulogd_MYSQL.so</H3> - -<P>An output plugin for logging into a mysql database. This is only compiled if -you have the mysql libraries installed, and the configure script was able to -detect them. (that is: --with-mysql was specified for ./configure) </P> - -<P>The plugin automagically inserts the data into the configured table; It -connects to mysql during the startup phase of ulogd and obtains a list of the -columns in the table. Then it tries to resolve the column names against keys of -interpreter plugins. This way you can easly select which information you want -to log - just by the layout of the table. </P> - -<P>If, for example, your table contains a field called 'ip_saddr', ulogd will -resolve this against the key 'ip.saddr' and put the ip address as 32bit -unsigned integer into the table. </P> - -<P>You may want to have a look at the file '<CODE>doc/mysql.table</CODE>' as an -example table including fields to log all keys from ulogd_BASE.so. Just delete -the fields you are not interested in, and create the table. </P> - -<P>The module defines the following configuration directives: -<DL> -<DT><B>table</B><DD><P>Name of the table to which ulogd should log</P> -<DT><B>ldb</B><DD><P>Name of the mysql database</P> -<DT><B>host</B><DD><P>Name of the mysql database host</P> -<DT><B>port</B><DD><P>TCP port number of mysql database server</P> -<DT><B>user</B><DD><P>Name of the mysql user</P> -<DT><B>pass</B><DD><P>Password for mysql</P> -</DL> -</P> - -<H3>ulogd_PGSQL.so</H3> - -<P>An output plugin for logging into a postgresql database. This is only compiled -if you have the mysql libraries installed, and the configure script was able to -detect them. (that is: --with-pgsql was specified for ./configure) </P> - -<P>The plugin automagically inserts the data into the configured table; It -connects to pgsql during the startup phase of ulogd and obtains a list of the -columns in the table. Then it tries to resolve the column names against keys of -interpreter plugins. This way you can easly select which information you want -to log - just by the layout of the table. </P> - -<P>If, for example, your table contains a field called 'ip_saddr', ulogd will -resolve this against the key 'ip.saddr' and put the ip address as 32bit -unsigned integer into the table. </P> - -<P>You may want to have a look at the file '<CODE>doc/mysql.table</CODE>' as an -example table including fields to log all keys from ulogd_BASE.so. Just delete -the fields you are not interested in, and create the table. </P> - -<P>The module defines the following configuration directives: -<DL> -<DT><B>table</B><DD><P>Name of the table to which ulogd should log</P> -<DT><B>db</B><DD><P>Name of the database</P> -<DT><B>host</B><DD><P>Name of the mysql database host</P> -<DT><B>port</B><DD><P>TCP port number of database server</P> -<DT><B>user</B><DD><P>Name of the sql user</P> -<DT><B>pass</B><DD><P>Password for sql user</P> -</DL> -</P> - -<H3>ulogd_PCAP.so</H3> - -<P>An output plugin that can be used to generate libpcap-style packet logfiles. -This can be useful for later analysing the packet log with tools like tcpdump -or ethereal.</P> -<P>The module defines the following configuration directives: -<DL> -<DT><B>file</B><DD><P>The filename where it should log to. The default is: -<CODE>/var/log/ulogd.pcap</CODE></P> -<DT><B>sync</B><DD><P>Set this to <CODE>1</CODE> if you want to have your pcap logfile written -synchronously. This may reduce performance, but makes your packets appear -immediately in the file on disk. The default is <CODE>0</CODE></P> -</DL> -</P> - -<H3>ulogd_SQLITE3.so</H3> - -<P>An output plugin for logging into a SQLITE v3 database. This is only compiled -if you have the sqlite libraries installed, and the configure script was able to -detect them. (that is: --with-sqlite3 was specified for ./configure) </P> - -<P>The plugin automagically inserts the data into the configured table; It -opens the sqlite db during the startup phase of ulogd and obtains a list of the -columns in the table. Then it tries to resolve the column names against keys of -interpreter plugins. This way you can easly select which information you want -to log - just by the layout of the table. </P> - -<P>If, for example, your table contains a field called 'ip_saddr', ulogd will -resolve this against the key 'ip.saddr' and put the ip address as 32bit -unsigned integer into the table. </P> - -<P>You may want to have a look at the file '<CODE>doc/sqlite3.table</CODE>' as an -example table including fields to log all keys from ulogd_BASE.so. Just delete -the fields you are not interested in, and create the table. </P> - -<P>The module defines the following configuration directives: -<DL> -<DT><B>table</B><DD><P>Name of the table to which ulogd should log</P> -<DT><B>db</B><DD><P>Name of the database</P> -<DT><B>buffer</B><DD><P>Size of the sqlite buffer</P> -</DL> -</P> -<H3>ulogd_SYSLOG.so</H3> - -<P>An output plugin that really logs via syslogd. Lines will look exactly like printed with traditional LOG target.</P> -<P>The module defines the following configuration directives: -<DL> -<DT><B>facility</B><DD><P>The syslog facility (LOG_DAEMON, LOG_KERN, LOG_LOCAL0 .. LOG_LOCAL7, LOG_USER)</P> -<DT><B>level</B><DD><P>The syslog level (LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR, LOG_WARNING, LOG_NOTICE, LOG_INFO, LOG_DEBUG)</P> -</DL> -</P> -<H2><A NAME="s5">5. QUESTIONS / COMMENTS</A></H2> - -<P>All comments / questions / ... are appreciated.</P> -<P>Just drop me a note to laforge@gnumonks.org</P> -<P>Please note also that there is now a mailinglist, ulogd@lists.gnumonks.org. -You can subscribe at -<A HREF="http://lists.gnumonks.org/mailman/listinfo/ulogd/">http://lists.gnumonks.org/mailman/listinfo/ulogd/</A></P> -<P> -The preferred method for reporting bugs is the netfilter bugzilla system, -available at -<A HREF="http://bugzilla.netfilter.org/">http://bugzilla.netfilter.org/</A>.</P> - -</BODY> -</HTML> |