docs: update Docker instructions

Dockerfile.md

@@ -0,0 +1,40 @@
+# Introduction
+furlzz in a Docker container works using `frida-portal` where the application is run and joined to the frida-portal.
+Once we did that we can use furlzz to connect to that portal and fuzz the application.
+
+## Building
+
+```bash
+$ git clone https://github.com/NSEcho/furlzz.git && cd furlzz/
+$ docker build -t furlzz .
+```
+
+![Building Docker image](./building_docker_image.png)
+
+## Usage
+
+Download `frida-portal` for your OS and architecture from [here](https://github.com/frida/frida/releases/latest) and run it as
+`sudo ./frida-portal-16.5.1-macos-arm64 --cluster-endpoint=0.0.0.0 --control-endpoint=0.0.0.0`.
+
+Make sure to note the IP address of the network which the device can reach (private IPv4 address assuming that both devices are on the same network).
+
+Then run the application and join the portal using `frida-join`.
+
+![Joining portal](./joining_portal.png)
+
+Once all these steps are finished, run `frida-ps` on the portal to get the correct name of the application (`frida-ps -H portalIPv4Address`).
+
+![Running frida-ps](./running_frida-ps.png)
+
+Now create your inputs directory and run the container.
+
+```bash
+$ mkdir inputs 
+$ echo -n '13333337' > ./inputs/1
+$ docker run -v /local/path/to/inputs/directory:/tmp/inputs -it --rm furlzz fuzz -b BASE_URL \
+-f FUNCTION_TO_APPLY_TO_INPUTS -i /tmp/inputs/ -t TIMEOUT \
+-m METHOD -a NAME_RETURNED_BY_FRIDA-PS -d OPTIONAL_DELEGATE \
+-n IPv4 address of the portal
+```
+
+![Fuzzing](./running_container.png)