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PRoot is a user-space implementation of chroot, mount --bind, and binfmt_misc. This means that users don't need any privileges or setup to do things like using an arbitrary directory as the new root filesystem, making files accessible somewhere else in the filesystem hierarchy, or executing programs built for another CPU architecture transparently through QEMU user-mode. Also, developers can use PRoot as a generic Linux process instrumentation engine thanks to its extension mechanism, see CARE for an example. Technically PRoot relies on ptrace, an unprivileged system-call available in every Linux kernel.
This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it.
USAGE: SEE SAMPLE OUTPUT
The file is composed of three parts:
a) The legible script (about 242 bytes)
b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242)
c) The actual filesystem
Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option.
PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :)
It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file.
The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables.
`mount -o remount` doesn't pick up new NFS options (eg. timeo, soft, retrans, etc) so you need to do a full mount/remount cycle. This one-liner makes it quick and easy :) Update your fstab with the new options, then run it.
In order to create a new encrypted filing system managed by cryptmount,
you can use the supplied 'cryptmount-setup' program, which can be used
by the superuser to interactively configure a basic setup.
Alternatively, suppose that we wish to setup a new encrypted filing
system, that will have a target-name of "opaque". If we have a free
disk partition available, say /dev/hdb63, then we can use this directly
to store the encrypted filing system. Alternatively, if we want to
store the encrypted filing system within an ordinary file, we need to
create space using a recipe such as:
dd if=/dev/zero of=/home/opaque.fs bs=1M count=512
cryptmount --generate-key 32 opaque
cryptmount --prepare opaque
cryptmount --release opaque
cryptmount -m opaque
cryptmount -u opaque
For detail see sample output
Unmounts all CIFS-based network drives. Very nice for shutting down network mounts on a Linux laptop just prior to going to sleep.
Assuming we have a disk image, created by dd if=/dev/sda of=image.dd we can check the image's partition layout with fdisk -ul image.dd, then substitute "x" with starting sector of the partition we want to mount. This example assumes that the disk uses 512Byte sectors
This one-liner is for cron jobs that need to provide some basic information about a filesystem and the time it takes to complete the operation. You can swap out the di command for df or du if that's your thing. The |& redirections the stderr and stdout to the mail command.
How to configure the variables.
FSCKDEV=`grep $TOFSCK /proc/mounts | cut -f1 -d" "`
MAILSUB="weekly file system check $TOFSCK "
Reports all local partitions having more than 90% usage.
Just add it in a crontab and you'll get a mail when a disk is full.
(sending mail to the root user must work for that)
This should automatically mount it to /media/truecrypt1. Further mounts will go to /media/truecrypt2, and so on. You shouldn't need sudo/su if your permissions are right.
I alias tru='truecrypt' since tr and true are commands.
To explicitly create a mount point do: tru volume.tc /media/foo
To make sure an GUI explorer window (nautilus, et al) opens on the mounted volume, add: --explorer
To see what you currently have mounted do: tru -l
To dismount a volume do: tru -d volume.tc. To dismount all mounted volumes at once do: tru -d
Tested with Truecrypt v6.3a / Ubuntu 9.10
mounts an ISO file to a directory on the target file system
mounts a samba share on a remote machine using a credentials file that can be in a file tht is not accessable by other users the file will look like:
best option i belive
since fuse mounts do not appear in /etc/mtab (fuse can't write there, dunno if it would if it could) this is propably a better way.
Instead of calculating the offset and providing an offset option to mount, let lomount do the job for you by just providing the partition number you would like to loop mount.
Yields entries in the form of "/dev/hda1" etc.
Use this if you are on a new system and don't know how the storage hardware (ide, sata, scsi, usb - with ever changing descriptors) is connected and which partitions are available.
Far better than using "fdisk -l" on guessed device descriptors.
The command is useful when, e.g., booting an existing system with a rescue or installation CD where you need to chroot into the hard-disk and be able to do stuff which accesses kernel info (e.g. when installing Ubuntu desktop with LVM2 you need to mount and chroot the hard disk from a shell window in order to install packages and run initramfs inside chroot).
The command assumes that /mnt/xxx is where the chroot'ed environment's root file system on the hard disk is mounted.
the middle command between the ; and ; is the vi commands that insert that line into the last line of the file, the esc with the carets is literally hitting the escape key, you have to have the smbfs package installed to do it, I use it to access my iTunes music on my mac from my linux PC's with amarok so I can play the music anywhere in the house. among other things, it allows you to access the files on that share from your computer anytime you're on that network.
connect to a remote server using ftp protocol over FUSE file system, then rsync the remote folder to a local one and then unmount the remote ftp server (FUSE FS)
it can be divided to 3 different commands and you should have curlftpfs and rsync installed
Particularly useful if you're mounting different drives, using the following command will allow you to see all the filesystems currently mounted on your computer and their respective specs with the added benefit of nice formatting.
Suppose you made a backup of your hard disk with dd:
dd if=/dev/sda of=/mnt/disk/backup.img
This command enables you to mount a partition from inside this image, so you can access your files directly.
Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img).
Saved my day, when my harddrive got stuck in read-only mode.