# Iptables Log parser

## How To

### Setup


1. Enable the custom logging template on `/etc/rsyslog.conf` as follows.

    ```
    template(name="MyIptablesTimestampFormat" type="string" string="tstamp=%timegenerated:::date-rfc3339% %HOSTNAME% %syslogtag% %msg%\n")
    if $msg startswith 'iptables:' then {
        action(type="omfile" file="/var/log/iptables.log" template="MyIptablesTimestampFormat")
        stop
    }
    ```
2. Make sure your iptables rules are inline with the condition you use on `rsyslog.conf`. As example my iptables log file starts with `iptables:` string so my `rsyslog.conf` condition is `...startswith 'iptables:'...`.

    ```
    iptables -A FORWARD -s 10.30.1.94/32 -d 192.168.0.0/16 -m limit --limit 1/min -j LOG --log-prefix "iptables: Vsphere "
    iptables -A FORWARD -s 10.30.1.70/32 -d 192.168.0.0/16 -m limit --limit 1/min -j LOG --log-prefix "iptables: RHEL "
    iptables -A FORWARD -s 10.30.1.52/32 -d 192.168.0.0/16 -m limit --limit 1/min -j LOG --log-prefix "iptables: Odoo "
    iptables -A FORWARD -s 10.30.1.105/32 -d 192.168.0.0/16 -m limit --limit 1/min -j LOG --log-prefix "iptables: OPNsense "
    ```


### Build

```c=
mkdir lib
#Compile the library
make parse_lib.so
```

### Execute

```bash=
 ./wrapper.py

```

## Structure

### wrapper.py

Reads, iptables.log and calls the  `lib/parser_lib.so`. Feed the parser library with lines from iptables log. 

### lib/parser_lib.so

Process the sed like operation on the line by line feeded by `wrapper.py`.

Current parsed values are :
- TimeStamp
- Source IP
- Destination IP
- Packet Length
- Interface IN
- Interface OUT
- Protocol