/sbin/cryptsetup not found on boot

Question

I've created an encrypted root partition using LUKS which contains a few LVM partitions. I can't boot and get the following output on startup:

Begin mounting root file system ... Begin: Running /scripts/local-top ... /scripts/local-top/cryptroot: line 1: /sbin/cryptsetup: not found

It still prompts me for the password:

Unlocking the disk /dev/sda5 (macbookcrypt)
Enter passphrase: *******************************
cryptsetup: cryptesetup failed, bad password or options?
/scripts/local-top/cryptroot: line 1: /sbin/cryptsetup: not found

Yet it fails every time.

My boot command-line is:

vmlinuz-3.13.0-37 generic ro root=/dev/mapper/macbooklvm-root cryptopts=target=macbookcrypt,source=/dev/sda5,lvm=macbooklvm recovery initrd=\initrd.img-3.13.0-37-generic

I've added "dm_crypt" to /etc/modules and then did update-initramfs to regenerate with dm_crypt included. I'm on Ubuntu 14.04 by the way.

In the initramfs shell, I can't seem to locate cryptsetup anywhere:

(initramfs) cat /proc/modules | grep crypt
dm_crypt 23177 0 - Live 0xffffffffa0006000
(initramfs) find / -iname "cryptsetup"
(initramfs)

It appears that the dm_crypt module is loaded', so that's good, but cryptsetup isn't present here. How do I install it to my Linux boot? Does it need to be included in initrd, vmlinuz, or System files somehow? I'm new to this hackery.

Answer 1

Evidently, I didn't create a /etc/crypttab file. Create one, then update-initramfs -u to fix the issue.

Answer 2

On Ubuntu 14.04 I was missing the xts kernel module from

/etc/initramfs-tools/modules

Other modules that you might miss could be:

raid1
raid456
aes-x86_64
sha512-ssse3
xts
dm-mod
dm-crypt

I found the root cause out by adding to the grub command line (linux) this option:

break=mount

that forces drop to busybox. After that I was able to copy by USB stick ( from another machine) these files on the ramfs:

mkdir /boot
mount /dev/sdc1 /boot
cp cryptsetup /sbin/cryptsetup
cp libcryptsetup.so.4.0.0 /lib/libcryptsetup.so.4
cp libpopt.so.0.0.0 /lib/libpopt.so.0
cp libgcrypt.so.11.7.0 /lib/libgcrypt.so.11
cp libgpg-error.so.0.8.0 /lib/libgpg-error.so.0
/boot/cryptsetup luksOpen /dev/md10 root

(I have also root on software raid, no LVM) that gave the error of missing module.

A good idea that came in my mind afterwards would be to copy the above cryptsetup files on the /boot partition in advance, so that you don't have to mess around with an USB stick. Another way is to decompress the initramfs image once (in advance) in e.g. /boot/tmp:

gzip -d < ../initrd.img-3.13.0-62-generic | cpio --extract --verbose --make-directories --no-absolute-filenames

so you have all the workings libs and cryptsetup available, even if your update-initramfs -k all -c has failed after some kernel update.

Answer 3

Another problem that gave me the above error message, but after investigation (as specified above) I got this more specific error message:

 cryptsetup luksOpen /dev/md10 cryptroot

 device-mapper: table: 252:0: crypt: unknown target type
 ioctl: error adding target to table

Solution: Check that /etc/crypttab root device name (cryptroot) matches /etc/initramfs-tools/conf.d/mdadm settings. I had "cryptroot" in other and "root" in other, after syncing the target device names, boot worked like a dream!

After fixing the settings run

update-initramfs -c -k all