OT: Password Managers?

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Wed, 15 Jun 2016 12:42:16 GMT in alt.home.repair, wrote:

Was it an intelligence test? rofl
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MID: <nb7u27$crn$ snipped-for-privacy@boaterdave.dont-email.me>
Hmmm. I most certainly don't understand how I can access a copy of a
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Tue, 14 Jun 2016 19:00:52 GMT in alt.home.repair, wrote:

Rot13 has been used on online forums and usenet for years to hide spoilers, demonstrate extremely 'weak' crypto, etc. It's like the answers to the crossword puzzle being printed upside down somewhere else on the page. It wasn't ever a UN*X only thing. Rot13 is a caeser cipher that because of the specific shift number, is inversing. IE: the same process used with no changes required will also decrypt encrypted material.

I'm not entirely sure what you mean by apparent distribution of symbols. Do you mean you haven't seen/heard of any which (for example) have the word frog to encrypt and begin writing the encrypted data, say, in reverse? Or do you mean that the encrypted message doesn't look like total garbage and things seem like you could determine what they represent? IE: you see a pattern. One or more symbols that may represent common letters?
If the latter, the Vigenere table does a very good job of eliminating patterns if used with a proper key. The issue only comes up if you're using a bad key. And by bad, one that's shorter than the message being encrypted by it and it doesnt consist of random characters. Instead, it's actually a word or a series of them,grouped together. This will certainly cause issue with the encryption process in so far as weakness to patterns, freq based attacks; including those discovered by Kerckhoffs, Friedman, and, Kasiski.
Now, concerning the caeser shift cipher...You don't need a significantly long message to crack a caeser shift cipher. A short sentence is often enough. And, If you know how a single letter should be deciphered, you then also know the shift amount (which is the real key to that cipher) and can decrypt the rest of the message with ease.
In other words, it looks like this (shift 5):
Plain - ABCDEFGHIJKLMNOPQRSTUVWXYZ Cipher- EFGHIJKLMNOPQRSTUVWXYZABCD
More about the Vigenere cipher:
http://simonsingh.net/The_Black_Chamber/v_square.html http://simonsingh.net/The_Black_Chamber/vigenere_strength.html http://math.ucsd.edu/~crypto/java/EARLYCIPHERS/Vigenere.html http://www.purdue.edu/discoverypark/gk12/downloads/Cryptography.pdf
An example of semi best practice encryption using the default offset style Vigenere cipher:
NonEncrypted Text Src: DWENLARLOVESYOU
Encrypted text result: NNOQQGRYEPHZEEC
Key used: krkdfganqudhgqituxnvbzmnajdigfug
The above short message is likely, not 'crackable' using any of the attack methods known for the cipher. The key is random and is longer than the message to be encrypted. Despite this, the key imho, could be made stronger by using more letters and/or reducing the unintended frequency of certain repeats too often. For the purposes of this though, it's solid enough.
Although this is still using the original Vigenere cipher and not a scrambled version (more on that below) due to details concerning the key covered above, the encrypted material is immune to the attacks created/devised by Friedman, Kasiski, and, Kerckhoffs. Kerckhoff had another trick up his sleeve so if you want to ensure you stop his attacks dead in their tracks, use the same principles as described above, but, use a scrambled version of the cipher instead.
A scrambled Vigenere cipher doesn't use shifting as the original does. Instead, each one of the 26 lines containing the alphabet has them in a preferably completely random order. The idea is to stop the shifting, as that makes the cipher potentially vulnerable to an attack devised by Kerckhoffs.
The Friedman, Kasiski, and, Kerckhoffs tests can't reliably be used for attack vectors when using the cipher modified as described above with a good key! As they rely on frequency analysis, poorly chosen keys, and stacked caeser cipher shifting.
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Wed, 15 Jun 2016 13:31:49 GMT in alt.home.repair, wrote:

Although it's not the worlds greatest password, it does put an end to most dictionary only style attacks.
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