On Tue, Feb 08, 2011 at 05:19:18PM +1100, Sridhar Dhanapalan wrote: > Following on from my question about OS images, does the XO check the > integrity of a firmware file before writing it? bootfw.zip files can > be checked against the CRC, but what about the .rom files?
bootfw.zip files contain a .rom file as payload. When processing a bootfw.zip file, the firmware checks that the cryptographic signature of the data hash of the payload matches the public key in the manufacturing data. If this check fails, the .rom file is not processed. The purpose of this check is to prevent installation of custom firmware that might bypass antitheft controls. When processing a .rom file (taken from a bootfw.zip file or not), the firmware checks an internal CRC in the file against the remainder of the file. The CRC is different for XO-1 and XO-1.5. If this check fails, an error is displayed and the SPI FLASH is unchanged. The purpose of this check is to prevent installation of accidentally corrupt firmware, which might brick a laptop. -- James Cameron http://quozl.linux.org.au/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
