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diff --git a/2003/netfilter-internals-kiblix2003/abstract b/2003/netfilter-internals-kiblix2003/abstract
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+Linux 2.4.x netfilter/iptables firewalling internals
+
+  The Linux 2.4.x kernel series has introduced a totally new kernel firewalling subsystem.  It is much more than a plain successor of ipfwadm or ipchains.
+
+  The netfilter/iptables project has a very modular design and it's
+sub-projects can be split in several parts: netfilter, iptables, connection
+tracking, NAT and packet mangling.
+
+  While most users will already have learned how to use the basic functions
+of netfilter/iptables in order to convert their old ipchains firewalls to
+iptables, there's more advanced but less used functionality in
+netfilter/iptables.
+
+  The presentation covers the design principles behind the netfilter/iptables
+implementation.  This knowledge enables us to understand how the individual
+parts of netfilter/iptables fit together, and for which potential applications
+this is useful.
+
+Topics covered:
+
+- overview about the internal netfilter/iptables architecture
+	- the netfilter hooks inside the network protocol stacks
+	- packet selection with IP tables
+	- how is connection tracking and NAT integrated into the framework
+- the connection tracking system
+	- how good does it track the TCP state?
+	- how does it track ICMP and UDP state at all?
+	- layer 4 protocol helpers (GRE, ...)
+	- application helpers (ftp, irc, h323, ...)
+	- restrictions/limitations
+- the NAT system
+	- how does it interact with connection tracking?
+	- layer 4 protocol helpers
+	- application helpers (ftp, irc, ...)
+- misc
+	- how far is IPv6 firewalling with ip6tables?
+	- advances in failover/HA of stateful firewalls
+	- ivisible firewalls with iptables on a bridge
+	- userspace packet queueing with QUEUE
+	- userspace packet logging with ULOG
+
+Requirements:  
+- knowledge about the TCP/IP protocol family
+- knowledge about general firewalling and packet filtering concepts
+- prior experience with linux packet filters
+
+Audience:
+- firewall administrators
+- network developers
diff --git a/2003/netfilter-internals-kiblix2003/biography b/2003/netfilter-internals-kiblix2003/biography
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+  <a href="http://gnumonks.org/users/laforge/">Harald Welte</a> is one 
+of the five <a href="http://www.netfilter.org/">netfilter/iptables</a> core
+team members, and the current Linux 2.4.x firewalling maintainer.  
+
+  His main interest in computing has always been networking.  In the few time
+left besides netfilter/iptables related work, he's writing obscure documents
+like the <a href="http://www.gnumonks.org/ftp/pub/doc/uucp-over-ssl.html"> UUCP
+over SSL HOWTO</a>.  Other kernel-related projects he has been contributing are
+user mode linux and the international (crypto) kernel patch.
+
+  In the past he has been working as an independent IT Consultant working on
+closed-source projecst for various companies ranging from banks to
+manufacturers of networking gear.  During the year 2001 he was living in
+Curitiba (Brazil), where he got sponsored for his Linux related work by 
+<a href="http://www.conectiva.com/">Conectiva Inc.</a>.
+
+  Starting with February 2002, Harald has been contracted part-time by
+<a href="http://www.astaro.com/">Astaro AG</a>, who are sponsoring him for his
+current netfilter/iptables work.
+
+  Harald is living in Berlin, Germany.
+
diff --git a/2003/netfilter-internals-kiblix2003/netfilter-internals-kiblix2003.mgp b/2003/netfilter-internals-kiblix2003/netfilter-internals-kiblix2003.mgp
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+%include "default.mgp"
+%default 1 bgrad
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+%nodefault
+%back "blue"
+
+%center
+%size 7
+
+
+Linux 2.4.x netfilter/iptables 
+firewalling internals
+
+
+%center
+%size 4
+by
+
+Harald Welte <laforge@netfilter.org>
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Contents
+
+
+	Introduction
+	Netfilter hooks in protocol stacks
+	Packet selection based on IP Tables
+	The Connection Tracking Subsystem
+	The NAT Subsystem based on netfilter + iptables 
+	Packet filtering using the 'filter' table
+	Packet mangling using the 'mangle' table
+	Advanced netfilter concepts
+	Current development and Future
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page 
+netfilter/iptables in Linux 2.4
+Introduction
+
+Why did we need netfilter/iptables?
+Because ipchains...
+
+		has no infrastructure for passing packets to userspace
+		makes transparent proxying extremely difficult
+		has interface address dependent Packet filter rules
+		has Masquerading implemented as part of packet filtering
+		code is too complex and intermixed with core ipv4 stack
+		is neither modular nor extensible
+		only barely supports one special case of NAT (masquerading)
+		has only stateless packet filtering
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Introduction 
+
+Who's behind netfilter/iptables
+		Paul 'Rusty' Russell
+			co-author of iptables in Linux 2.2
+			was paid by Watchguard for about one Year of development
+		James Morris
+			userspace queuing (kernel, library and tools)
+		Marc Boucher
+			NAT and packet filtering controlled by one command
+			Mangle table
+		Harald Welte 
+			Conntrack+NAT helper infrastructure (newnat)
+			Userspace packet logging (ULOG)
+		Jozsef Kadlecsik
+			TCP window tracking
+			H.323 conntrack + NAT helper
+		Non-core team contributors
+			http://www.netfilter.org/scoreboard/
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Netfilter Hooks
+
+What is netfilter?
+
+		System of callback functions within network stack
+		Callback function to be called for every packet traversing certain point (hook) within network stack
+		Protocol independent framework
+		Hooks in layer 3 stacks (IPv4, IPv6, DECnet, ARP)
+		Multiple kernel modules can register with each of the hooks
+		Asynchronous packet handling in userspace (ip_queue)
+
+Traditional packet filtering, NAT, ... is implemented on top of this framework
+
+Can be used for other stuff interfacing with the core network stack, like DECnet routing daemon.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Netfilter Hooks
+
+Netfilter architecture in IPv4
+%font "typewriter"
+%size 4
+
+   --->[1]--->[ROUTE]--->[3]--->[4]--->
+                 |            ^
+                 |            |
+                 |         [ROUTE]
+                 v            |
+                [2]          [5]
+                 |            ^
+                 |            |
+                 v            |
+
+%font "standard"
+1=NF_IP_PRE_ROUTING
+2=NF_IP_LOCAL_IN
+3=NF_IP_FORWARD
+4=NF_IP_POST_ROUTING
+5=NF_IP_LOCAL_OUT
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Netfilter Hooks
+
+Netfilter Hooks
+
+	Any kernel module may register a callback function at any of the hooks
+
+	The module has to return one of the following constants
+
+		NF_ACCEPT	 continue traversal as normal
+		NF_DROP		 drop the packet, do not continue
+		NF_STOLEN	 I've taken over the packet do not continue
+		NF_QUEUE	 enqueue packet to userspace
+		NF_REPEAT	 call this hook again
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+IP tables
+
+Packet selection using IP tables
+
+		The kernel provides generic IP tables support
+
+		Each kernel module may create it's own IP table
+
+		The three major parts of 2.4 firewalling subsystem are implemented using IP tables
+			Packet filtering table 'filter'
+			NAT table 'nat'
+			Packet mangling table 'mangle'
+
+		Can potentially be used for other stuff, i.e. IPsec SPDB
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+IP Tables
+
+Managing chains and tables
+
+	An IP table consists out of multiple chains
+	A chain consists out of a list of rules
+	Every single rule in a chain consists out of
+		match[es] (rule executed if all matches true)
+		target (what to do if the rule is matched)
+
+%size 4
+matches and targets can either be builtin or implemented as kernel modules
+
+%size 5
+	The userspace tool iptables is used to control IP tables
+		handles all different kinds of IP tables 
+		supports a plugin/shlib interface for target/match specific options
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+IP Tables
+
+Basic iptables commands
+
+	To build a complete iptables command, we must specify
+		which table to work with
+		which chain in this table to use
+		an operation (insert, add, delete, modify)
+		one or more matches (optional)
+		a target
+
+The syntax is
+%font "typewriter"
+%size 3
+iptables -t table -Operation chain -j target match(es)
+%font "standard"
+%size 5
+
+Example:
+%font "typewriter"
+%size 3
+iptables -t filter -A INPUT -j ACCEPT -p tcp --dport smtp
+%font "standard"
+%size 5
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+IP Tables
+
+Matches
+		Basic matches
+			-p			protocol (tcp/udp/icmp/...)
+			-s			source address (ip/mask)
+			-d			destination address (ip/mask)
+			-i			incoming interface
+			-o			outgoing interface
+
+		Match extensions (examples)
+			tcp/udp		TCP/udp source/destination port
+			icmp			ICMP code/type
+			ah/esp		AH/ESP SPID match
+			mac		 	source MAC address
+			mark 		nfmark
+			length		match on length of packet
+			limit			rate limiting (n packets per timeframe)
+			owner	 	owner uid of the socket sending the packet
+			tos			TOS field of IP header
+			ttl			TTL field of IP header
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+IP Tables
+
+Targets 
+	very dependent on the particular table.
+
+	Table specific targets will be discussed later
+
+	Generic Targets, always available
+		ACCEPT		accept packet within chain
+		DROP		silently drop packet
+		QUEUE		enqueue packet to userspace
+		LOG		log packet via syslog
+		ULOG		log packet via ulogd
+		RETURN		return to previous (calling) chain
+		foobar		jump to user defined chain
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page 
+netfilter/iptables in Linux 2.4
+Packet Filtering
+
+Overview
+
+	Implemented as 'filter' table
+	Registers with three netfilter hooks
+
+		NF_IP_LOCAL_IN (packets destined for the local host)
+		NF_IP_FORWARD (packets forwarded by local host)
+		NF_IP_LOCAL_OUT (packets from the local host)
+
+Each of the three hooks has attached one chain (INPUT, FORWARD, OUTPUT)
+
+Every packet passes exactly one of the three chains. Note that this is very different compared to the old 2.2.x ipchains behaviour.
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Packet Filtering
+
+Targets available within 'filter' table
+
+	Builtin Targets to be used in filter table
+		ACCEPT	accept the packet
+		DROP	silently drop the packet 
+		QUEUE	enqueue packet to userspace
+		RETURN	return to previous (calling) chain
+		foobar	user defined chain
+
+	Targets implemented as loadable modules 
+		REJECT	drop the packet but inform sender
+		MIRROR	change source/destination IP and resend
+		LOG  	log via syslog
+		ULOG	log via userspace
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Connection Tracking Subsystem
+
+	Connection tracking...
+		implemented seperately from NAT 
+		enables stateful filtering 
+		implementation
+			hooks into NF_IP_PRE_ROUTING to track packets
+			hooks into NF_IP_POST_ROUTING and NF_IP_LOCAL_IN to see if packet passed filtering rules
+			protocol modules (currently TCP/UDP/ICMP)
+			application helpers currently (FTP,IRC,H.323,talk,SNMP)
+		divides packets in the following four categories
+			NEW - would establish new connection
+			ESTABLISHED - part of already established connection
+			RELATED - is related to established connection
+			INVALID - (multicast, errors...)
+		does _NOT_ filter packets itself
+		can be utilized by iptables using the 'state' match 
+		is used by NAT Subsystem
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+HA for netfillter/iptables
+Connection Tracking Subsystem
+
+Common structures
+	struct ip_conntrack_tuple, representing unidirectional flow
+		layer 3 src + dst 
+		layer 4 protocol
+		layer 4 src + dst
+	connetions represented as struct ip_conntrack
+		original tuple
+		reply tuple
+		timeout
+		l4 state private data
+		app helper
+		app helper private data
+		expected connections
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+HA for netfillter/iptables
+Connection Tracking Subsystem
+
+Flow of events for new packet
+	packet enters NF_IP_PRE_ROUTING
+		tuple is derived from packet
+		lookup conntrack hash table with hash(tuple) -> fails
+		new ip_conntrack is allocated
+			fill in original and reply == inverted(original) tuple
+			initialize timer
+			assign app helper if applicable
+			see if we've been expected -> fails
+			call layer 4 helper 'new' function
+	...
+	packet enters NF_IP_POST_ROUTING
+		do hashtable lookup for packet -> fails
+		place struct ip_conntrack in hashtable			
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+HA for netfillter/iptables
+Connection Tracking Subsystem
+
+Flow of events for packet part of existing connection
+	packet enters NF_IP_PRE_ROUTING
+		tuple is derived from packet
+		lookup conntrack hash table with hash(tuple)
+		assosiate conntrack entry with skb->nfct
+		call l4 protocol helper 'packet' function
+			do l4 state tracking
+			update timeouts as needed [i.e. TCP TIME_WAIT,...]
+	...
+	packet enters NF_IP_POST_ROUTING
+		do hashtable lookup for packet -> succeds
+		do nothing else
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Network Address Translation
+
+Overview
+
+		Previous Linux Kernels only implemented one special case of NAT: Masquerading
+		Linux 2.4.x can do any kind of NAT.
+		NAT subsystem implemented on top of netfilter, iptables and conntrack
+		NAT subsystem registers with all five netfilter hooks
+		'nat' Table registers chains PREROUTING, POSTROUTING and OUTPUT
+		Following targets available within 'nat' Table
+			SNAT changes the packet's source whille passing NF_IP_POST_ROUTING
+			DNAT changes the packet's destination while passing NF_IP_PRE_ROUTING
+			MASQUERADE is a special case of SNAT
+			REDIRECT is a special case of DNAT
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Network Address Translation
+
+	Source NAT
+		SNAT Example:
+%font "typewriter"
+%size 3
+iptables -t nat -A POSTROUTING -j SNAT --to-source 1.2.3.4 -s 10.0.0.0/8
+%font "standard"
+%size 4
+
+		MASQUERADE Example:
+%font "typewriter"
+%size 3
+iptables -t nat -A POSTROUTING -j MASQUERADE -o ppp0
+%font "standard"
+%size 5
+
+	Destination NAT
+		DNAT example
+%font "typewriter"
+%size 3
+iptables -t nat -A PREROUTING -j DNAT --to-destination 1.2.3.4:8080 -p tcp --dport 80 -i eth1
+%font "standard"
+%size 4
+
+		REDIRECT example
+%font "typewriter"
+%size 3
+iptables -t nat -A PREROUTING -j REDIRECT --to-port 3128 -i eth1 -p tcp --dport 80
+%font "standard"
+%size 5
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Packet Mangling
+
+	Purpose of mangle table
+		packet manipulation except address manipulation
+	Integration with netfilter
+		'mangle' table hooks in all five netfilter hooks
+		priority: after conntrack
+	Targets specific to the 'mangle' table:
+		DSCP - manipulate DSCP field
+		IPV4OPTSSTRIP - strip IPv4 options
+		MARK - change the nfmark field of the skb
+		TCPMSS - set TCP MSS option
+		TOS - manipulate the TOS bits 
+		TTL - set / increase / decrease TTL field
+Simple example:
+%font "typewriter"
+%size 3
+iptables -t mangle -A PREROUTING -j MARK --set-mark 10 -p tcp --dport 80
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Advanced Netfilter concepts
+
+%size 4
+	Userspace logging
+		flexible replacement for old syslog-based logging
+		packets to userspace via multicast netlink sockets
+		easy-to-use library (libipulog)
+		plugin-extensible userspace logging daemon (ulogd)
+		Can even be used to directly log into MySQL
+
+	Queuing
+		reliable asynchronous packet handling 
+		packets to userspace via unicast netlink socket
+		easy-to-use library (libipq)
+		provides Perl bindings
+		experimental queue multiplex daemon (ipqmpd)
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+netfilter/iptables in Linux 2.4
+Current Development and Future
+
+Netfilter (although it proved very stable) is still work in progress. 
+
+	Areas of current development
+		infrastructure for conntrack manipulation from userspace
+		failover of stateful firewalls (conntrack sync)
+		making iptables layer3 independent (pkttables)
+		new userspace library (libiptables) to hide plugins from apps
+		more matches and targets for advanced functions (pool, hashslot)
+		more conntrack and NAT modules (RPC, SNMP, SMB, ...)
+		better IPv6 support (conntrack, more matches / targets)
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%page
+Future of Linux packet filtering
+Thanks
+
+	Thanks to
+		the BBS people, Z-Netz, FIDO, ...
+			for heavily increasing my computer usage in 1992
+		KNF
+			for bringing me in touch with the internet as early as 1994
+			for providing a playground for technical people
+			for telling me about the existance of Linux!
+		Alan Cox, Alexey Kuznetsov, David Miller, Andi Kleen
+			for implementing (one of?) the world's best TCP/IP stacks
+		Paul 'Rusty' Russell
+			for starting the netfilter/iptables project
+			for trusting me to maintain it today
+		Astaro AG
+			for sponsoring parts of my netfilter work
+%size 3
+	The slides and the an according paper of this presentation are available at http://www.gnumonks.org/
+%size 3
+	The netfilter homepage http://www.netfilter.org/
+