Skip to content

Instantly share code, notes, and snippets.

@nathany
Created June 16, 2011 06:45
Show Gist options
  • Star 6 You must be signed in to star a gist
  • Fork 4 You must be signed in to fork a gist
  • Save nathany/1028790 to your computer and use it in GitHub Desktop.
Save nathany/1028790 to your computer and use it in GitHub Desktop.
Decode Mac Open Firmware Password
# I forgot the firmware password on my MacBook Air and didn't want to take it in:
# http://support.apple.com/kb/TS2391
# info
# http://paulmakowski.blogspot.com/2009/03/apple-efi-firmware-passwords.html
# run the following command to retrieve your obfuscated firmware password:
# sudo nvram -p | grep security-password
security_password = "%..."
# take the complement of every second bit:
decode_byte = lambda byte: chr(int(byte, 16) ^ int('10101010',2))
# decode the security password, which contains %-prefixed hex values:
decode = lambda pwd: "".join([decode_byte(x) for x in pwd.split('%') if x != ''])
print(decode(security_password))
@nathany
Copy link
Author

nathany commented Jun 16, 2011

As much as I appreciate being able to recover my password, Apple should really be using a one-way SHA digest so that it's actually secure.

@darkhelmet
Copy link

roflcopter

@darkhelmet
Copy link

ROFL:ROFL:LOL:ROFL:ROFL
_|
L /
LOL=== []
L ______________
| |
-------------/

@darkhelmet
Copy link

Well that roflcopter failed...

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment