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As I mentioned in the comment, you can't trust javascript served by the server. The idea of keeping the client side downloaded on their computers is interesting, although that doesn't really solve the issue. The server can still include javascript as part of a response unless you are insanely careful. In this case I really wouldn't go with javascript. ...


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AES-128 for encryption because it's faster and supposedly as secure as -256 Yes and no. If you plan on storing your data for a long time, and you're worried about post-quantum attacks, 256-bit might be the better option. Grover's algorithm reduces the time complexity of cracking a 128-bit key down to about 264, which is likely feasible. For 256-bit it ...


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Theoretically, yes, but you're going to run into storage limits. As an example, back-of-the-envelope math: Passwords of length: <12 Salt length: 32 bytes salt&password combinations: 6x10100 (~6x1088 TB). The total storage capacity of all computers on the planet is roughly 10 zettabytes, or 8x1010 TB, so good luck storing this table. I've also ...


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As has been said, it is theoretically possible but due to computational and storage limitations practically far beyond possible: Calculating a rainbow table for the entire hash space of an hashing algorithm is impossible as pointed out here. Not to speak of larger hashes like SHA-512 or SHA3. There exist rainbow tables for MD5 covering simple passwords ...


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The value of salt is not in its secrecy, it's in its differentiation and the added complexity. You've touched on this a bit. First, two passwords hashed with different salts have different resulting hashes. Therefore, an attacker cannot look at a password table and discover users who share the same password. Second, as you write, a rainbow table could be ...


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Yes it would, but this is computationally impossible as of today. The salt technically expands your password by so and so random but known characters. You could therefore build a "salted rainbow table" with all passwords combinations up to n characters with, for each password, all salts of m characters (m is known). But this is not computationally feasible ...


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Yes, there's fundamentally no security difference to what you are doing as the result will have the same "strength" of hash. Operationally though the two methods will return completely different hashes, which might a problem if you will be using this to authenticate to a different system. Appending the salt is the conventional way to do it, if you reverse ...



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