ATA-3 Standart for Hard disk drivers brings a disaster in laptop unlocking - Security Mode Feature Set. With a device lock password, a user can prevent unauthorized access to hard disk device even if the device is removed from the computer. some features are:
New Commands :
Security Set Password
Security Freeze Lock
Security Erase Unit
Security Freeze Lock
Security Disable Password
Security modes :
Device Locked mode : The device disables media access commands after power on. Media access commands are enabled by either a security unlock command or a security erase unit command.
Device Unlocked mode : The device enables all commands. If a password is not set this mode is entered after power on, otherwise it is entered by a security unlock or a security erase unit command.
Device Frozen mode : The device enables all commands except those which can update the device lock function, set/change password. The device enters this mode via a Security Freeze Lock command. It cannot quit this mode until power off.
Security levels :
High level security : When the device lock function is enabled and the User Password is forgotten the device can be unlocked via a Master Password.
Maximum level security : When the device lock function is enabled and the User Password is forgotten then only the Master Password with a Security Erase Unit command can unlock the device. Then user data is erased.
Master Password : When the Master Password is set, the device does NOT enable the Device Lock Function, and the device can NOT be locked with the Master Password, but the Master Password can be used for unlocking the device locked.
User Password : The User Password should be given or changed by a system user. When the User Password is set, the device enables the Device Lock Function, and then the device is locked on next power on reset or hard reset.
So, after reading this section please understand following :
a) Hard disks can be unlocked
b) Password is stored in hard disk drive itself.
to be continued ...
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