From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Mon, 6 Feb 2012 17:34:52 +0100 Subject: [U-Boot] Integity validation (checksum) of a squashfs root file system In-Reply-To: References: Message-ID: <201202061734.52127.marek.vasut@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de > Hi, > > I would like to validate the integrity (checksum) of a squashfs root file > system before starting Linux. > > Current strategy I am using is: > - Wrap squashfs rootfs inside a u-boot image > - TFTP download on the target > - Download validation using iminfo > - Save squashfs rootfs in flash without the image header (Linux failed to > load squashfs rootfs if u-boot image is present) > > Problems: > - I need to hardcode squashfs rootfs offset in u-boot image in order to be > able to flash it - U-Boot image header information (size, crc, ...) is > lost after a reboot. It is not possible to check the integrity of the > flash content. > > I would like to save some fields of u-boot image header (size, crc, ...) > in u-boot environment variables. And then do an integrity check at boot > time. > > I have not find a way to extract those fields and save them without > changing u-boot code. I have added some code to ?iminfo? command to set > environment variables for CRC, size, payload offset, timestamp. > > Is it an acceptable way of doing it? > Is there a better way of doing it? > > Thanks in advance, > > Pascal Use sha1sum integrated into uboot and stick it at the end? M