Create a hard-to-guess password

dd if=/dev/urandom bs=16 count=1 2>/dev/null | base64
Alternatively, if your password can contain a richer character set, try using 'uuencode' rather than base64. dd if=/dev/urandom bs=16 count=1 2>/dev/null | uuencode - Sample of that: '0:.CF\-@"\`W315VG^4O\.@``'
Sample Output
a5sXvbJx0pUY/CEuxwM4YA==

0
2009-02-05 19:19:20
dd

These Might Interest You

  • Function: char * crypt (const char *key, const char *salt) The crypt function takes a password, key, as a string, and a salt character array which is described below, and returns a printable ASCII string which starts with another salt. It is believed that, given the output of the function, the best way to find a key that will produce that output is to guess values of key until the original value of key is found. The salt parameter does two things. Firstly, it selects which algorithm is used, the MD5-based one or the DES-based one. Secondly, it makes life harder for someone trying to guess passwords against a file containing many passwords; without a salt, an intruder can make a guess, run crypt on it once, and compare the result with all the passwords. With a salt, the intruder must run crypt once for each different salt. For the MD5-based algorithm, the salt should consist of the string $1$, followed by up to 8 characters, terminated by either another $ or the end of the string. The result of crypt will be the salt, followed by a $ if the salt didn't end with one, followed by 22 characters from the alphabet ./0-9A-Za-z, up to 34 characters total. Every character in the key is significant. For the DES-based algorithm, the salt should consist of two characters from the alphabet ./0-9A-Za-z, and the result of crypt will be those two characters followed by 11 more from the same alphabet, 13 in total. Only the first 8 characters in the key are significant. Show Sample Output


    0
    useradd -m -p $(perl -e'print crypt("pass", "mb")') user
    mariusbutuc · 2010-09-03 19:00:56 0
  • The crypt function takes a password, key, as a string, and a salt character array which is described below, and returns a printable ASCII string which starts with another salt. It is believed that, given the output of the function, the best way to find a key that will produce that output is to guess values of key until the original value of key is found. from http://en.wikipedia.org/wiki/Crypt_(Unix)


    1
    useradd -m -p $(perl -e'print crypt("passwordscelta", "stigghiola")') user
    0disse0 · 2012-02-06 19:53:01 2
  • You can also use sha1sum and variants for longer passwords Show Sample Output


    -5
    echo "A great password" | md5sum
    ubersoldat · 2009-04-24 14:32:56 4
  • create and md5 sum of your password without it showing up in your terminal or history. Afterwards we overwrite the $p variable (thx to bazzargh) Show Sample Output


    1
    read -s p && echo -n $p | md5sum;p=
    hoodie · 2012-06-08 13:50:50 4

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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