Red Hat Bugzilla – Bug 846140
crypttab tab man page password section needs to be updated
Last modified: 2016-11-25 08:08:36 EST
I am coming from the "Community": Scientific Linux 6.2, 64 bit. Would one of our interpret heroes at Red Hat please fix this for me?
I just encrypted my backup drives. In the process, I found that the man page for crypttab is missing a bunch of necessary stuff that causes all kinds of problems. Please reference the following bugs:
Crypttab does not mount volume at boot
That being said, I would like to suggest some change to the crypttab manual page:
Old section for parameter three (password):
The third field specifies the encryption password. If the field is not present or the password is set to none, the password has to be manually entered during system boot. Otherwise the field is interpreted as a path to a file containing the encryption password. For swap encryption /dev/urandom can be used as the password file; using /dev/random may prevent boot completion if the system does not have enough entropy to generate a truly random encryption key.
Proposed new section three:
The third field specifies the encryption password. This field does not support spaces, whether escaped with back slashes or quotes. Back slashes or quotes will cause this field to be interpreted as a path to a password file. If you wish to use a password with spaces in it, please use a password file.
If the field is not present or the password is set to none, the password has to be manually entered during system boot. Otherwise the field is interpreted as a path to a file containing the encryption password.
If using a password file, please note that the entire contents of the password file is used, including all lines and any hidden characters you can not see with a text editor ("vi" and "vi -b" included) such as line feeds. A password file without a line feed can be created with the "echo" command's "-n" option. For example:
echo -n "pass phrase" > MyPasswordFile
You can test for the presence of a line feed in your password file with "hexdump -c". For example
hexdump -c MyPasswordFile
0000000 p a s s p h r a s e
The lack of a "\n" at the end means you do not have a line feed at the end of your file.
For swap encryption /dev/urandom can be used as the password file; using /dev/random may prevent boot completion if the system does not have enough entropy to generate a truly random encryption key.
Thanks for the manpage update, I will update it in next release.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.