[dm-crypt] password -md5 in grub.conf/menu.lst

[dm-crypt] password -md5 in grub.conf/menu.lst

[ken]

In grub/menu.lst file my /boot partition is a line like this:

password --md5 $1$Mb9vxXPV$pAbcdTxr4Twh32XXgns2/

The last bit is 35 characters long.


Is this the hash digest of the passphrase?  Is the final slash character
(/) just another character or is it in some way especially significant?

tnx

Re: [dm-crypt] password -md5 in grub.conf/menu.lst

[Arno Wagner]

This seems to be a config file option of grub-md5-crypt,
and has nothing to do with cryptsetup, dm-crypt or LUKS.

If I understand the documentation correctly, this is
an md5-ed password that either secures interactive Grub mode
or prevents script continuation before password entry.

The format seems to be the same as in /etc/shadow
for md5 passwords. You can read up on it here:

http://en.wikipedia.org/wiki/Shadow_password

Arno



On Wed, Aug 17, 2011 at 10:17:16AM -0400, ken wrote:
> 
> In grub/menu.lst file my /boot partition is a line like this:
> 
> password --md5 $1$Mb9vxXPV$pAbcdTxr4Twh32XXgns2/
> 
> The last bit is 35 characters long.
> 
> 
> Is this the hash digest of the passphrase?  Is the final slash character
> (/) just another character or is it in some way especially significant?
> 
> tnx
> _______________________________________________
> dm-crypt mailing list
> dm-crypt@saout.de
> http://www.saout.de/mailman/listinfo/dm-crypt
> 

-- 
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name 
GnuPG:  ID: 1E25338F  FP: 0C30 5782 9D93 F785 E79C  0296 797F 6B50 1E25 338F
----
Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans

If it's in the news, don't worry about it.  The very definition of 
"news" is "something that hardly ever happens." -- Bruce Schneier 

Re: [dm-crypt] password -md5 in grub.conf/menu.lst

[Arno Wagner]

P.S.: The "/" is an artefact of the encoding, no special
      meaning. It can be one of 4 characters. The hash gets
      patted by "1111" (binary) at the end.

On Wed, Aug 17, 2011 at 05:50:31PM +0200, Arno Wagner wrote:
> This seems to be a config file option of grub-md5-crypt,
> and has nothing to do with cryptsetup, dm-crypt or LUKS.
> 
> If I understand the documentation correctly, this is
> an md5-ed password that either secures interactive Grub mode
> or prevents script continuation before password entry.
> 
> The format seems to be the same as in /etc/shadow
> for md5 passwords. You can read up on it here:
> 
> http://en.wikipedia.org/wiki/Shadow_password
> 
> Arno
> 
> 
> 
> On Wed, Aug 17, 2011 at 10:17:16AM -0400, ken wrote:
> > 
> > In grub/menu.lst file my /boot partition is a line like this:
> > 
> > password --md5 $1$Mb9vxXPV$pAbcdTxr4Twh32XXgns2/
> > 
> > The last bit is 35 characters long.
> > 
> > 
> > Is this the hash digest of the passphrase?  Is the final slash character
> > (/) just another character or is it in some way especially significant?
> > 
> > tnx
> > _______________________________________________
> > dm-crypt mailing list
> > dm-crypt@saout.de
> > http://www.saout.de/mailman/listinfo/dm-crypt
> > 
> 
> -- 
> Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name 
> GnuPG:  ID: 1E25338F  FP: 0C30 5782 9D93 F785 E79C  0296 797F 6B50 1E25 338F
> ----
> Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans
> 
> If it's in the news, don't worry about it.  The very definition of 
> "news" is "something that hardly ever happens." -- Bruce Schneier 
> _______________________________________________
> dm-crypt mailing list
> dm-crypt@saout.de
> http://www.saout.de/mailman/listinfo/dm-crypt
> 

-- 
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name 
GnuPG:  ID: 1E25338F  FP: 0C30 5782 9D93 F785 E79C  0296 797F 6B50 1E25 338F
----
Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans

If it's in the news, don't worry about it.  The very definition of 
"news" is "something that hardly ever happens." -- Bruce Schneier