Name
crypt
Synopsis
crypt string, salt
Used by the passwd function on Unix systems to
produce a unique 13-character string (stored in the system’s
password file) from the first 8 characters of the given
string and the 2-character
salt. The Perl function operates the
same way and returns a 13-character string with the first 2
characters as the salt. crypt uses a modified version of the
Data Encryption Standard, which produces a one-way encryption; the
resulting string cannot be decrypted to determine the original
string. crypt can be used to
check that a password is correct by comparing the string from the
function to the string found in /etc/passwd
(if you have permission to do this):
if (crypt ($guess, $pass) eq $pass) {
# guess is correct
}The variable $pass is the
password string from the password file. crypt merely uses the first two
characters from this string for the
saltargument.