Random Password generator with 2 digits and 6 characters Post: 303024060

Sponsored Content

Top Forums Shell Programming and Scripting Random Password generator with 2 digits and 6 characters Post 303024060 by Don Cragun on Thursday 27th of September 2018 08:40:37 PM

09-27-2018

Registered User

This was tested on macOS (instead of AIX), but it should work on AIX as well:

Code:

#!/bin/ksh
LC_ALL=C tr -dc '[:alnum:]' < /dev/urandom | dd cbs=60 conv=unblock | awk '
{	#print "Input line read:", $0
	for(i = 1; i <= length($0); i++)
		a[i] = (substr($0, i, 1) ~ /[[:alpha:]]/)
	for(i = 1; i <= length($0) - 7; i++) {
		if((n = (a[i] + a[i+1] + a[i+2] + a[i+3] + \
		       a[i+4] + a[i+5] + a[i+6] + a[i+7])) == 6) {
		   	printf("Found password \"%s\"\n", substr($0, i, 8))
			exit
		}#else	printf("Tried \"%s\" %d alpha, %d num\n",
		#	    substr($0, i, 8), n, 8 - n)
	}
}'

If you remove the # characters from the above script, it will show you the input it got from /dev/urandom and the possible passwords it tested from that input before reaching a password that meets your criteria.

Note that the dd in the pipeline is because standard implementations of awk are defined to work on text files while the output from the tr command is a single incomplete line of infinite length (while a text file is limited to lines containing no more than LINE_MAX bytes (where LINE_MAX is 2048 bytes on most UNIX systems)). Having dd produce lines of 61 characters per line (counting the terminating <newline> character) was a choice to make the debugging output easy to read in an 80 column window. If you don't care about the debugging output, you might want to increase the line size slightly. Note, however, that even with a line length of just 60 characters, I only saw this script read a second line of input once in 50 tests with debugging output enabled. Furthermore, if you are using an awk that can handle "unlimited" line lengths, the algorithm used in this script will not make any attempt to look for a password until a complete line has been read.

Don Cragun

View Public Profile for Don Cragun

Find all posts by Don Cragun

9 More Discussions You Might Find Interesting

1. Cybersecurity

Password Generator

I need a great Password Generator program. I looked at a few of them, but none of them seemed to be what I wanted. So I have decided to write my own. (That's the cool thing about being a programmer....I always get what I want in software :) ) Do you have any password generators that you...

2. Solaris

Does Solaris have a random number generator?

I am trying to find a way to generate random numbers within a shell script. Does Solaris have a utility that will generate random numbers? Thanks in advance. B

3. Shell Programming and Scripting

Random Sentence Generator

Hi, I need to create a table with random sentences. I need lines that are upto 1000 characters in lenght. I need a random sentence generator that will create sentences and output it to a text file. The sentences should be of lenght varying from 1 to 1000. Does anyone know how this can be...

4. Shell Programming and Scripting

How to replace characters with random characters

I've got a file (numbers.txt) filled with numbers and I want to replace each one of those numbers with a new random number between 0 and 9. This is my script so far: #!/bin/bash rand=$(($RANDOM % 9)) sed -i s//$rand/g numbers.txtThe problem that I have is that it replaces each number with just...

5. Shell Programming and Scripting

Need specialized random string generator script

Hi, I need a script that will generate a set of random strings in sequence, with the ability to predetermine the length, quantity, and alphabet of individual string, and to use the outputs of earlier strings in the sequence to define the parameters of later strings. For examples, I might want...

6. Ubuntu

expect script for random password and random commands

Hi I am new to expect. Please if any one can help on my issue its really appreciable. here is my issue: I want expect script for random passwords and random commands generation. please can anyone help me? Many Thanks in advance

7. Cybersecurity

swordfish --- a password generator

Here is my new password generation script. The attachment, swordfish.txt, is in dos format. Remember that you need to use dos2unix or flip or something to get it into unix format. The script is self documenting. It has an extensive help system built-in. And you can run: swordfish "set...

8. UNIX for Dummies Questions & Answers

A crude random byte generator...

There was an upload recently on generating a pseudo-random file when /dev/random does NOT exist. This does not need /dev/random, /dev/urandom or $RANDOM either... (I assume $RANDOM relies on the /dev/random device in some way.) This code uses hexdump just because I like hexdump for ease of...

9. Shell Programming and Scripting

awk (or) UNIX random RGB colors generator?

Dear UNIX Friends, I was wondering if there is a random RGB color generator or any function in any unix platforms. Please share your ideas. Thanks

LEARN ABOUT MINIX

dd

DD(1)							      General Commands Manual							     DD(1)

NAME

       dd - disk dumper

SYNOPSIS

       dd [option = value] ...

EXAMPLES

       dd if=/dev/fd0 of=/dev/fd1
			   # Copy disk 0 to disk 1

       dd if=x of=y bs=1w skip=4
			   # Copy x to y, skipping 4 words

       dd if=x of=y count=3
			   # Copy three 512-byte blocks

DESCRIPTION

       This  command  is  intended  for  copying  partial  files.  The block size, skip count, and number of blocks to copy can be specified.  The
       options are:

	 if = file    - Input file (default is stdin)
	 of = file    - Output file (default is standard output)
	 ibs = n      - Input block size (default 512 bytes)
	 obs = n      - Output block size (default is 512 bytes)
	 bs = n       - Block size; sets ibs and obs (default is 512 bytes)
	 skip = n     - Skip n input blocks before reading
	 seek = n     - Skip n output blocks before writing
	 count = n    - Copy only n input blocks
	 conv = lcase - Convert upper case letters to lower case
	 conv = ucase - Convert lower case letters to upper case
	 conv = swab  - Swap every pair of bytes
	 conv = noerror- Ignore errors and just keep going
	 conv = silent- Suppress statistics (Minix specific flag)

       Where sizes are expected, they are in bytes.  However, the letters w, b, or k may be appended to the number to indicate	words  (2  bytes),
       blocks  (512 bytes), or K (1024 bytes), respectively.  When dd is finished, it reports the number of full and partial blocks read and writ-
       ten.

SEE ALSO

       vol(1).

																	     DD(1)