On 12/16/2017 01:03 AM, Maciek Borzecki wrote: > On Fri, Dec 15, 2017 at 8:37 PM, Foxtrot Mike via arch-general > <arch-general@xxxxxxxxxxxxx> wrote: >> Note: This is not an Arch related question. I tried asking this question elsewhere, but didnt get any useful response. In the past I have received very helpful responses on this mail list so I am posting this here in the hope that someone would be willing/able to help me out. >> >> Hi, >> >> I am able to telnet into a router that's running a customized linux firmware. It was compiled using 'buildroot'. >> >> I was able to dig out some specs of the router. I intend to clone the router's firmware for further study. 'dd' is not available so I tried using cat to throw the entire contents of the flash drive (mtdblock0) to my pc using netcat: >> >> Router: >> cat /dev/mtdblock0 | nc ip port >> >> PC: >> nc -lp port > routerFirmware >> >> Then on my PC I used 'binwalk' to examine the downloaded file. The result is: >> >> DECIMAL HEXADECIMAL DESCRIPTION >> -------------------------------------------------------------------------------- >> 0 0x0 Squashfs filesystem, little endian, non-standard signature, version 4.0, compression:gzip, size: xxxxxxx bytes, xxx inodes, blocksize: xxxxxx bytes, created: xxxx-xx-xx xx:xx:xx >> >> Seems good so far. But '# unsquash routerFlash' results in: >> >> Can't find a SQUASHFS superblock on routerFlash >> >> The most probable reason I think is that 'cat' and 'nc' are not able to clone the entire flash as I intend. I am stuck here. Any help would be appreciated! > It's possible that squashfs used to build the image carried some > vendor modifications. Is not that uncommon actually. You can try your > luck with: https://github.com/devttys0/sasquatch or > https://github.com/rampageX/firmware-mod-kit > > Cheers, Thanks a lot for the very helpful pointer. I got it working with sasquatch. Turns out the file is actually compressed with lzma, not gzip as was reported by unsquash. Regards,
