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ClueBot NG (talk | contribs) m Reverting possible vandalism by 182.1.197.29 to version by Suffusion of Yellow. Report False Positive? Thanks, ClueBot NG. (4332491) (Bot) |
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{{SHA-box}}
A '''cryptographic hash function''' ('''CHF''') is a [[hash algorithm]] (a [[map (mathematics)|map]] of an arbitrary binary string to a binary string
* the probability of a particular <math>n</math>-bit output result ([[hash value]]) for a random input string ("message") is <math>2^{-n}</math> ('''as for any good hash'''), so the hash value can be used as a representative of the message;
* finding an input string that matches a given hash value (a ''pre-image'') is unfeasible, ''assuming all input strings are equally likely.'' The ''resistance'' to such search is quantified as [[security strength]], a cryptographic hash with <math>n</math> bits of hash value is expected to have a ''preimage resistance'' strength of <math>n</math> bits, unless the space of possible input values is significantly smaller than <math>2^{n}</math> (a practical example can be found in {{section link||Attacks on hashed passwords}});
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