taint.org: Justin Mason’s Weblog

• Hacking Mifare Transport Cards : notable mainly because Schneier calls MIFARE Classic’s crypto ‘terrible’ and ‘kindergarten cryptography’. ‘Anyone with any security experience would be embarrassed to put his name to the design.’ ZING
  (tags: ouch mifare cracks security zing crypto-cards smartcards oyster nxp)

• some good AWS tips : e.g. “upload files to S3 in lexically-sorted order”, apparently it’s faster. who knew!? (Sorry Joshua, gave you a bad tip y’day in that case)
  (tags: amazon aws s3 sqs sdb web-services hosting for:joshua)

• The Coreflood Report : fascinating Joe Stewart post-mortem of a server run by a Russian malware group targeting online banking; one apparent Miami-based victim was defrauded of $90k, and it appears that the group would have had access to a combined $2.5m in all victims’ accounts
  (tags: coreflood trojans joe-stewart secureworks malware banking online-banking autoproxy joe-lopez)

• using “data=writeback” on your Ubuntu filesystems : aha! This is the root cause of the crippling Firefox 3/VIM slowness; Ubuntu and Debian use a crappy ext3 option which sacrifices speed for correctness, by effectively turning every fsync() into a sync(). Here’s how to disable it
  (tags: fsync sync unix linux ext3 ubuntu debian firefox vim grub annoying sysadmin)

Tags: amazon, annoying, autoproxy, aws, banking, coreflood, cracks, crypto-cards, debian, ext3, firefox, for:joshua, fsync, grub, hosting, joe-lopez, joe-stewart, linux, malware, mifare, nxp, online-banking, ouch, oyster, s3, sdb, secureworks, security, smartcards, sqs, sync, sysadmin, trojans, ubuntu, unix, vim, web-services, zing

I took the plunge over the weekend, and live-upgraded the new ‘Dapper Drake’ Ubuntu release — ouch. Here’s the two key lessons I learned:

• Don’t run “grub-install” in a misremembered attempt to update the current GRUB boot menu ‘menu.lst’ file with the new kernel; sadly, this will quietly remove important details from your old menu.lst, such as “initrd” lines, rendering those kernels unbootable. Moral: ensure brain is in gear before meddling with MBRs!

• If you’re a Kubuntu user, watch out. Ensure you run apt-get install ubuntu-base ubuntu-desktop — bringing the entirety of GNOME up to date — as well as apt-get install kubuntu-desktop after the upgrade; it appears that some part of a new hotplugging subsystem is not included as a dependency of kubuntu-desktop. Failure to do this results in an inability to use USB/hotpluggable devices, including internal devices like the Synaptics touchpad. No pointer devices (mice or touchpads) means no X server at boot, which is always a little annoying.

Some day I’ll just do things the right way, and do a fresh-from-CD install instead. Ah well. The good stuff: the new kernel, or possibly Xorg, is proving to be a lot speedier — window updates are noticeably smoother; and the new Ubuntu GNOME theme is similarly tasty.

Tags: dapper, gnome, grub, kde, kubuntu, linux, software, ubuntu, upgrades

Tech: January 24th, besides being the date the first Apple Macintosh went on sale, is supposedly the day of maximal post-xmas misery. Well, it certainly was for me today.

I decided to power on my old desktop to set it up as a back-room fileserver, and twiddled the partition table accordingly to nuke a few unused Windows partitions and maximise usable space.

Somehow or other, some component of my system decided that it would henceforth be non-bootable. It seems some BIOSes don’t like partition tables where a high-numbered logical partition have a lower starting sector than a boot logical partition, or something… GRUB just errored out with an obscure ‘Error 17′, which apparently means that it couldn’t find its boot partition any more.

OK, so I needed a boot disk. But I had 1 laptop with a CD/DVD drive but no floppy drive, and a desktop with a floppy drive but no CD drive (due to hardware failure)… and the original linux boot floppy was long gone, seeing as I’d hardly booted this machine in the duration of two house moves. Argh.

A dinky little Cruzer mini 128MB USB flash drive saved the day. (R)ecovery (I)s (P)ossible is a tiny Linux distro that fits into 27MB, well inside the USB drive’s limits; it has an exceptionally helpful and detailed README detailing exactly what needs to be done to create a bootable USB flash drive from its ISO image, using just the generic linux toolchain.

Together with fdisk and parted’s ‘rescue a lost partition’ mode, I was able to get the mangled partition table back into shape, mount the boot disk, change the fstab and grub configuration file, and reboot into a working system. phew!

Many thanks to Kent Robotti, who’s done a great job with RIP.

On the other hard — no thanks to whoever came up with the arcane rules behind the IDE partition table… argh.

Tags: boot, day, desktop, disk, drive, grub, linux, partition, table, tech, usb