🚀 go-pugleaf

In <NEWTNews.807898837.21140.shah@shah.wg.com>, shah@wg.com writes:
>
>Hi there !
>
>I am developing a windows 3.1 app.  This app needs to authenticate a user 
>login by the user name and his/her password.  I need to store this password in 
>some sort of a format in some sort of a file (maybe an ini file).  But first I 
>need to encrypt this password and later on de-crypt to check against the 
>entered password (or maybe there is a better way - I just don't know yet).  
>Could any of you please point me in a better way or point me to some known 
>used technique for this procedure ?

The best way I know of is to use a one-way function or a hash function.  This is essentially an algorithm
that takes some data and encrypts it in such a fashion that the original information cannot be recovered
in any way (hence the name one-way function).  The ciphered data is unique!! ie there is a one to one
mapping from input to output.  Thus when a user sets a password, the cipher text is computed and stored
(in a clear file).  When the user then enters his password, the password is passed through the same algorithm
and then compared with the stored cipher text.  If they are the same the password is accepted.  This means that
the ciphered password never has to be deciphered which means that it is difficult to break.  I believe this technique
is used extensively for storing and checking passwords in Unix.

Cheers
   Bruce Diesel