There is currently only one HID gadget available: hid_payload, although others are in the works. It emulates a keyboard in a similar way to the USB Rubber Ducky. The main file of importance is /boot/usbninja/hid.txt (accessible on partition one of the MicroSD card). The format is very similar to (and indeed heavily influenced by ) Hak5's DuckyScript. In fact, any DuckyScript file should also work with the USB Ninja, but some of the more advanced functions (like looping) are yet to be implemented and will simply be ignored.
If you are having trouble using this gadget to do with the host OS not recognizing the keystrokes quick enough, then you can try setting the delay options in options.txt. The value needs to be an integer and represents the number of milliseconds to leave inbetween successive HID packets.
NOTE: Pressing a key (or combination of keys) and releasing them counts as TWO HID packets. This means that if you set delay too high, the OS could end up thinking that the keys are being held too long and you'll get doubles of everything (think what happens if you hold the A key for more than half a second or so).
The following will open notepad.exe on Windows and type "Hello, World!". As you can see, it is very straightforward.
DELAY 5000
GUI r
DELAY 1000
PRINT notepad
ENTER
DELAY 1000
PRINT Hello, World!
"Instructives" are the name given to the first word of each line in hid.txt. Anything not listed here will simply be ignored, so commenting your payloads becomes trivial!
Below are currently supported instructives:
DELAY <int> # Sleep for <int> many milliseconds.
PRINT <str> # Type out <str>, see further down for the supported characters.
ENTER # Press the ENTER key. Aliased by "RETURN".
ESC # Press the ESC key.
DEL # Press the DEL key.
TAB # Press the TAB key.
SPACE # Press the SPACE bar.
CAPS # Press the CAPS LOCK button.
F1-F12 # Press one of the function keys F1-F12.
PRNTSCRN # Press the PRINTSCREEN key.
SCROLLOCK # Press the SCROLL LOCK key.
PAUSE # Press the PAUSE key.
INSERT # Press the INSERT key.
HOME # Press the HOME key.
PGUP # Press the PAGE UP key.
PGDWN # Press the PAGE DOWN key.
END # Press the END key.
RIGHT # Press the RIGHT arrow key.
LEFT # Press the LEFT arrow key.
UP # Press the UP arrow key.
DOWN # Press the DOWN arrow key.
CLEAR # Press the CLEAR key.
VOLUP # Press the Volume Up button.
VOLDOWN # Press the Volume Down button.
CTRL <key> # Press CTRL + <key>
ALT <key> # Press ALT + <key>
GUI <key> # Press GUI + <key>
SHIFT <key> # Press SHIFT + <key>
The CTRL, ALT, GUI and SHIFT keys are known as modifiers and can be coupled together like CTRL ALT DEL and CTRL SHIFT ENTER. In fact, you could even have all four as in CTRL ALT SHIFT GUI a, if you really wanted to.
NOTE: The order of the modifiers is irrelevant. CTRL ALT DEL is exactly the same as ALT CTRL DEL. The only requirement is that the key (i.e. not one of the modifiers) is the last word on the line.
E.g. CTRL ALT DEL and ALT CTRL DEL are fine (and equivalent!) but CTRL DEL ALT is not!
When using the PRINT instructive, it may be useful to have a list of the currently supported characters.
A-Z
a-z
0,1,2,3,4,5,6,7,8,9
! " # $ % ^ & * ( ) _ + - =
[ ] ; ' , . / { } : @ ~ < > ?
| \ ` ¬
NOTE: Support for multiple keyboard layouts is currently in development. Currently it defaults to en_US, so even though I have an en_GB keyboard, the key that reads "£" (SHIFT + 3 usually) actually outputs "#".
In extra.go, a map hex_codes is defined which contains all the mappings for each key (bar a select few). It's here that all the "translation" is done when we parse through hid.txt and lookup each character in the string following a PRINT instructive. If a line in hid.txt doesn't start with the PRINT instructive, then the parser will check to see if the leading word exists in hex_codes.
Once the hex_code is looked up then the hid_packet is built as an array of strings. Eventually this HID packet will be echoed out to /dev/hidg0.