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Aug
5
awarded  Informed
Aug
5
comment Achieving 256-bit encryption strength with PBKDF2 - HMAC-SHA1
@Henrik - I would also appreciate it if you could explain why applying the Skein hash "before" is stronger than applying "after". The only thing that comes to my amaturish mind is that this would be the case only if the intial password strength was more than 160 bits (for simplicity of the argument I assume here just 1 iteration through the PBKDF2), thus being strength-truncated by the SHA1.
Aug
5
comment Achieving 256-bit encryption strength with PBKDF2 - HMAC-SHA1
@Henrik - Thank you for an interesting proposition. So if I understood you correctly, I'd pass my password through a Skein hash function, take two different sets of 160 bit each from the function output, feed each set separately to the PBKDF2 - HMAC-SHA1, and then concatenate the two PBKDF2's results to get 256+ (probabely 320 bit) key strength. Neat. This is what I will do.
Aug
5
comment Achieving 256-bit encryption strength with PBKDF2 - HMAC-SHA1
@hunter - added comment: The question is still this: will a 160-bit key strength become 256 bit stregth by passing it through a Skein hash function. I understand that there are arguments that the entropy of the system is as strong as the input's entropy, but the hash action of "mangling" the bits must add to the "chaos" of the result, thus increasing its "strength" against brute-forcing.
Aug
5
comment Achieving 256-bit encryption strength with PBKDF2 - HMAC-SHA1
@hunter - I am aware that in practical terms that iteration count is too small. I provided that number just as an example so I could easily convey, in my example, a simple number of added "strength".
Aug
4
comment Achieving 256-bit encryption strength with PBKDF2 - HMAC-SHA1
The option to change the hash function in my current implementation is too much of a programming effort due to some reasons related to the usage environment. I am trying to achieve the wanted "strength" in an easier way - as I proposed with the Skein function.
Aug
3
awarded  Editor
Aug
3
revised Achieving 256-bit encryption strength with PBKDF2 - HMAC-SHA1
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Aug
3
asked Achieving 256-bit encryption strength with PBKDF2 - HMAC-SHA1