Cryptographic Hashes | Computer Security

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A cryptographic hash function is a function, H 𝐻 , that when applied on a message, M 𝑀 , can be used to generate a fixed-length “fingerprint” of the message. As such, any change to the message, no matter how small, will change many of the bits of the hash value with there being no detectable patterns as to how the output changes based on specific input changes. In other words, any changes to the message, M 𝑀 , will change the resulting hash-value in some seemingly random way. The hash function, H 𝐻 , is deterministic, meaning if you compute H ( M ) 𝐻 ( 𝑀 ) twice with the same input M 𝑀 , you will always get the same output twice. The hash function is unkeyed, as it only takes in a message M 𝑀 and no secret key. This means anybody can compute hashes on any message. Typically, the output of a hash function is a fixed size: for instance, the SHA256 hash algorithm can be used to hash a message of any size, but always produces a 256-bit hash value. In a secure hash function

Cryptographic Hashes | Computer Security Skip to main content Menu Expand (external link) Document Search Copy Copied Computer Security 7. Cryptographic Hashes 7.1. Overview A cryptographic hash function is a function, \(H\), that when applied on a message, \(M\), can be used to generate a fixed-length “fingerprint” of the message. As such, any change to the message, no matter how small, will change many of the bits of the hash value with there being no detectable patterns as to how the output changes based on specific input changes. In other words, any changes to the message, \(M\), will chan

Cryptographic Hashes | Computer Security

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