Password encryption at client side
Possible Duplicate:
About password hashing system on client side
I have to secure the passwords of my web site users. What I did was use MD5 encryption hashing in server side. But the problem is the passwords remain in plain text until it arrives at the server, which means that the password can be captured using traffic monitoring. So what I want is to use a client side password encryption/hashing mechanism and send the encrypted/hashed password.
Can anybody tell what is the way to do this?
Answer
This won't be secure, and it's simple to explain why:
If you hash the password on the client side and use that token instead of the password, then an attacker will be unlikely to find out what the password is.
But, the attacker doesn't need to find out what the password is, because your server isn't expecting the password any more - it's expecting the token. And the attacker does know the token because it's being sent over unencrypted HTTP!
Now, it might be possible to hack together some kind of challenge/response form of encryption which means that the same password will produce a different token each request. However, this will require that the password is stored in a decryptable format on the server, something which isn't ideal, but might be a suitable compromise.
And finally, do you really want to require users to have javascript turned on before they can log into your website?
In any case, SSL is neither an expensive or especially difficult to set up solution any more