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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.
This was tested on Ubuntu 12.04 (Precise) LTS Server. It returns the name of the symlink within /dev/disk/by-id for the physical drive you specify. Change /dev/sda to the one you want, and replace ata- with scsi- or the appropriate type for your drive.
I used this to pre-configure grub-pc during a non-interactive install because I had to tell it which disk to install grub on, and physical disks don't have a UUID such as that blkid provides.
Remove empty lines additionally:
tr -s ' \t\n' <1.txt >2.txt
tr -s '[:space:]' <1.txt >2.txt
To "clean perfectly" a text or code file, You can combine this command with
while read l; do echo -e "$l"; done <1.txt >2.txt
(= remove all leading and trailing spaces or tabs from all lines of a text file)
Not always does Xorg run on :0. For times like those, this script allows you to find out which it is.
tr has some predefined sets of characters that are more convenient to use than characters codes
Generate a 18 character password from character set a-zA-Z0-9 from /dev/urandom, pipe the output to Python which prints the password on standard out and in crypt sha512 form.
This command will encode a string using the ROT47 cipher.
Lauching an app including jars in an adjacent lib folder to its classpath
Also shows files as they are found. Only works from a tty.
Copying and pasting from Office documents open in Office:mac can dirty your files with Windows CRLF and (inexplicably) Classic Mac OS LF newlines, which can break some tools. This snippet replaces them with good ol' Unix LF newlines.
If there are spaces won't work.
Convert long list of ' ' to a single space. Compress space and other characters.
Translates first set into second set