[SOLVED] uuencode for random password generation with /dev/urandom

JZL240I-U · 07-03-2007, 06:24 AM

I somewhere read how to produce a random password:

Code:

dd if=/dev/urandom bs=1 count=20 | uuencode

On my SUSE there is a mime_uuencode which doesn't deliver though. What am I missing here? Or rather, how is this done with SUSE?

wjevans_7d1@yahoo.co · 07-03-2007, 06:37 AM

I don't know anything particular about SUSE, but I'll bet the following will work on any distribution:

Code:

dd if=/dev/urandom bs=1 count=20 | uuencode x | head -2 | tail -1

Hope this helps.

JZL240I-U · 07-03-2007, 06:40 AM

Thank you, but no, it won't since ole SuSE 10.0 somehow doesn't come with uuencode. That's why I posted here in the SUSE Forum. What are SUSE-users using instead? Or alternatively what am I doing wrong?

wjevans_7d1@yahoo.co · 07-04-2007, 06:40 AM

I've waited for about 24 hours for a SUSE person to respond. Sigh.

Ok, try this:

Code:

dd if=/dev/urandom bs=1 count=20 | md5sum | cut '-d ' -f1

JZL240I-U · 07-06-2007, 01:22 AM

Thank you wjevans_7d1@yahoo.com.

Your solution looks like a good idea, I'll try it over the weekend. In the meantime I resolved the basic issue ... would you believe it "uuencode" is part of the distribution but simply was not installed

. I do apologize to any-/everybody *blush*.

After I installed "uuencode" I got results, but only with upper case letters -- not that optimal for creating random passwords with a greater variety in their character pool. Md5sum should do nicely.

Thanks again, wjevans_7d1@yahoo.com

wjevans_7d1@yahoo.co · 07-07-2007, 08:21 AM

If you don't like the uuencode solution because of no lower case letters, then md5sum will be even worse, because all you get are hex digits.

Try this perl script, removing what you don't want:

Code:

#!/usr/bin/perl
$a=`dd if=/dev/urandom bs=1 count=90`;
$a=~s/[\x00-\*]//g;      # eliminate low  characters
$a=~s/[\x7f-\xff]//g;    # eliminate high characters
$a=~s/\\\;\?\`\~//g;     # eliminate other characters which might be awkward
$a=substr($a,0,20);      # limit it to 20 characters
print("$a\n");

JZL240I-U · 07-12-2007, 06:38 AM

Right. Found that out about md5sum too

. Thanks for the script, I'll try it soonest (thought that might still be in about a month).

Again, thank you.

wjevans_7d1@yahoo.co · 07-13-2007, 05:36 AM

I just looked at my script again and found three bugs. Corrected script:

Code:

#!/usr/bin/perl

$a=`dd if=/dev/urandom bs=1 count=90`;
chomp($a);

$a=~s/[\x00-\ *]//g;     # eliminate low  characters
$a=~s/[\x7f-\xff]//g;    # eliminate high characters
$a=~s/[\\\;\?\`\~]//g;   # eliminate other characters which might be awkward
$a=substr($a,0,20);      # limit it to 20 characters

print("$a\n");

JZL240I-U · 08-13-2007, 02:43 AM

Okay, back again.

I tried your script and got the nasty

answer:

Code:

bash: Cannot execute binary file <file name>

Perl is installed.

I can also type "perl" at the prompt, which produces a blank line. When I copy the script there an press return no result and no error is printed out.

What is perl expecting from me? What do I do wrong?

wjevans_7d1@yahoo.co · 08-14-2007, 12:17 AM

What happens when you try this script?

Code:

#!/usr/bin/perl
print("Hello, world!\n");

JZL240I-U · 08-16-2007, 03:12 AM

Result of the test script (exactly as on my screen):

Code:

print("Hello,: bad interpreter: file or directory not found

What's that supposed to tell me?

Btw this is version perl5.8.7-linux-thread-multi

wjevans_7d1@yahoo.co · 08-17-2007, 12:02 AM

This is very strange.

Presumably you placed the two-liner in a file somewhere, changed the protection to 700, and then said

Code:

./whateverfilename

Correct?

JZL240I-U · 08-17-2007, 01:57 AM

Yes, indeed (I may have omitted the leading "./" though). I even copied it from your post on a floppy to take it home so as to be sure not to accidentally include a typo of my own making...

What now? Might there be some missing perl modules (in particular the printing module)? What perl files constitute a complete installation, i.e. could you post the perl directory from your machine?

JZL240I-U · 08-17-2007, 09:27 AM

Something to smile over?

http://ars.userfriendly.org/cartoons/?id=20070806

wjevans_7d1@yahoo.co · 08-19-2007, 09:27 AM

Does any Perl script work on your system?