Such a dense title deserves a dense application, but Firewater is a fairly simple tool with a singular purpose: unlock the bootloader and provide S-OFF to owners of modern HTC devices.
While HTC already provides a developer portal that unlocks the bootloader of their various devices, the process maintains the S-ON flag that prevents users from really messing with their phones’ underlying software.
XDA member, regaw_leinad, wrote a great primer on S-OFF, the crux of which is below:
“What this security does is protect the NAND partitions (ie: the boot partition, the recovery partition, the radio, the system partition…) from being permanently modified at all. Basically, all changes made to these partitions while the phone is running is not permanent, and will be reset upon a reboot. Also, while your phone is S-ON, all firmware zips (ie: PJ75IMG.zip) must be digitally signed by HTC in order to be flashed through the bootloader.
When your device is set to S-OFF, the security is turned off. This allows you to modify any partition on the device, and changes will not be reset upon a reboot. Also, the signature checking of the firmware zips (ie: PJ75IMG.zip) is disabled, allowing users to flash unsigned firmware zips containing the separate images of the partitions. S-OFF gives the user great power over the device, but also comes with much responsibility to be careful.”
Firewater is an abd-based tool that does most of the work for you, and will leave your HTC One, One X, One S, etc., with a security flag that lets you flash RUU’s from other regions and change the engineering bootloader, among other things.
The prerequisites are short, but important:
- Working adb on your PC. Yes, that means OS X, linux, Windows, etc. are all supported.
- HTC drivers installed and working
- HTC sync removed (not closed – REMOVED)
- All other phone software removed or disabled (Samsung Kies, PDANet, etc.)
- A working internet connection ON YOUR DEVICE – wifi, 3g, 4g, etc. are all supported. There is no way around this requirement, don’t ask.
- USB debugging enabled on your device
- Your device must be HTCDEV unlocked/rooted or have a working temproot. A temproot that works with many modern (not all) HTC devices is provided below.
- Do not attempt to run firewater from a terminal emulator on your device. You MUST use adb along with a PC.
- A supported device. firewater *should* work with most modern HTC devices, including (but not limited to) the htc one, droid dna, one s, one max, and many others.
If you’re prepared to abide by these rules, head to Firewater for more.