diff --git a/sec/ex-3_iptables.adoc b/sec/ex-3_iptables.adoc index 283466c..190e884 100644 --- a/sec/ex-3_iptables.adoc +++ b/sec/ex-3_iptables.adoc @@ -121,7 +121,9 @@ The lowercase word on top is the table and the upper case word below is the chai **All interfaces are handled the same way; it's up to you to define rules that treat them differently.** Of course some packets + - are intended for local processes, hence come in from the top of the chart and stop at **Local Proces**, + - while other packets are generated by local processes; hence start at **Local Process** and proceed downward through the flowchart. A detailed explanation [https://www.frozentux.net/iptables-tutorial/iptables-tutorial.html#TRAVERSINGOFTABLES here]. @@ -182,8 +184,9 @@ Tables consist of **chains**, which are lists of rules which are followed in ord ==== Filter -This is the default table. Its built-in chains are: +This is the default table. +.Its built-in chains are: [source,bash] ---- Input: packets going to local sockets @@ -193,8 +196,10 @@ This is the default table. Its built-in chains are: ==== Nat -When a packet creates a new connection, this table is used. Its built-in chains are: +When a packet creates a new connection, this table is used. + +.Its built-in chains are: [source,bash] ---- Prerouting: designating packets when they come in @@ -204,8 +209,9 @@ When a packet creates a new connection, this table is used. Its built-in chains ==== Mangle -Used for special altering of packets. Its chains are: +Used for special altering of packets. +.Its built-in chains are: [source,bash] ---- Prerouting: incoming packets @@ -217,8 +223,9 @@ Used for special altering of packets. Its chains are: ==== Raw -Primarily used for configuring exemptions from connection tracking. The built-in chains are +Primarily used for configuring exemptions from connection tracking. +.Its built-in chains are: [source,bash] ---- Prerouting: packets that arrive by the network interface @@ -227,8 +234,9 @@ Primarily used for configuring exemptions from connection tracking. The built-in ==== Security -Used for Mandatory Access Control (MAC) rules. After the filter table, the security table is accessed next. The built-in chains are: +Used for Mandatory Access Control (MAC) rules. After the filter table, the security table is accessed next. +.Its built-in chains are: [source,bash] ---- Input: packets entering the server