added readme

for download and upload through the gontrol server

README.md

@@ -1,3 +1,79 @@
 # gommand
 
-A standalone shell with remote access through the browser
+A standalone shell including remote access through your browser.
+
+The shell has multiple features:
+
+* Fully interactive shell in your browser
+* Upload and download through to the browser
+* Bash/emacs like controls
+* Persistent color themes
+* Resize rows and columns in interactive and non interactive shell by resizing
+  the browser window
+* Connect to a control server like [gontrol](https://git.stefan.works/whx/gontrol)
+
+## Execute gommand
+
+Just start the binary, the TCP the shell is running on port will be chosen randomly.
+If not sufficient, the port to connect directly to the shell can be chosen via
+`-interactive-port` followed by your preferred TCP port. Furthermore, you can
+chose the network interface `gommand` is using.
+
+To connect `gommand` as an agent to a
+[gontrol](https://git.stefan.works/whx/gontrol) C2 server, you can setup the IP
+address and port. By default VPN interfaces like IPSec and wireguard will be
+prioritized higher by `gommand`. That means if the network interface has not
+been chosen manually, The first VPN interfaces will be used.
+
+```sh
+$ gommand --help
+
+Usage of gommand:
+  -interactive-port string
+        Port to connect directly to the agent's webapp. Port will be random if not set.
+  -network-interface string
+        Network interface to bind to. Will bind to the first non loopback interface if not set. VPN interfaces will be preferred.
+  -server-address string
+        IP Address of the C2 server. (default "127.0.0.1")
+  -server-port string
+        Websocket port of the C2 server. (default "5555")
+```
+
+## Usage
+
+Once the binary of the shell has been executed on the target you can open the
+shell via browser connection. The TCP port will be chosen randomly if not set
+as a parameter at startup.
+
+Connect to the shell by putting IP address and port into the address input bar
+of your browser.
+
+Once you have opened the shell in your browser use it like any other command
+line interface. You are greeted by the non interactive shell mode. This
+includes uploading, downloading and setting the color theme  of the shell. You
+can switch to a completely interactive shell from here.
+
+Type help inside the shell to get more information:
+
+```sh
+$ help
+
+This is a shell in the browser, a web shell.
+
+It includes a non-interactive shell with an optional interactive mode.
+Furthermore, additional commands to ease communications between server
+and client.
+
+  Available Commands:
+    upload            Upload files to the server through the file selector of the browser.
+    download <file>   Download files from the server to your local download directory.
+    theme <theme>     Change the colorscheme of the shell. Type theme to get an overview of all colorschemes.
+    start-interactive Opens a shell in an interactive terminal. Type ctrl+d to go back to non-interactive mode.
+```
+
+### Interactive Mode
+
+Use the command `start-interactive` to switch to an interactive shell. Once
+activated you can use binaries and shell-builtins which need interaction. For
+example `less`, `vim`, your favorite package manager or initial connection to a
+server using `ssh`.