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zeruniverse / Password-Manager

An online keepass-like tool to manage password. client-side AES encryption!
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confkey and reducedinfo #175

Closed BenjaminHae closed 7 years ago

BenjaminHae commented 7 years ago

May I remove confkey and reducedinfo? They both just seem to add some obscurity which doesn't really increase security. In the case of reducedinfo I even suspect that it reduces the size of the space of possible keys for the pbkdf2 algorithm so in the end we get less entropy for the key and thus make it (a little bit) easier to break.

zeruniverse commented 7 years ago

I think when I designed this, I tried to avoid brute-force attack. Users might use weak login passwords. In this case, even if the attacker logs in, he doesn't know whether the retrieved password is correct.

On Sat, May 13, 2017 at 10:13 PM Benjamin Häublein notifications@github.com wrote:

May I remove confkey and reducedinfo? They both just seem to add some obscurity which doesn't really increase security. In the case of reducedinfo I even suspect that it reduces the size of the space of possible keys for the pbkdf2 algorithm so in the end we get less entropy for the key and thus make it (a little bit) easier to break.

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BenjaminHae commented 7 years ago

As far as I can tell the reducedinfo is used to both authentication and for generating the key, so in case an attacker logs in he automatically has access to everything. For accessing the data it won't make a difference if he has got the correct password or a collision.

zeruniverse commented 7 years ago

I think the confkey used the original password.

BenjaminHae commented 7 years ago

Confkey is only used in get_orig_pwd and gen_temp_pwd which look like implementations of the caesar cipher or something related?

zeruniverse commented 7 years ago

It's remapping characters in passwords. So the one decrypted from AES is not immediately correct

zeruniverse commented 7 years ago

If you have more questions, please reopen it.