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# SHAmwow
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Sometimes you just want to understand how your hashing algorithms work, so you implement them yourself.
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It should go without saying that this was just for fun, and you should never, ever, _ever_ roll your own cryptography primatives for any purpose other than education!
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## sha1
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The sha1 function in `shamwow.rb` implements the SHA1 hashing function in Ruby, outputting the 160-bit hash as a hexadecimal string.
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### sources
* wikipedia's pseudocode breakdown: < https: // en . wikipedia . org / wiki / SHA-1 # Examples_and_pseudocode >
## sha2
The sha2 function in `shamwow.rb` implements the SHA-256 hashing function in Ruby, outputting the 256-bit hash as a hexadecimal string.
### Sources
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* the actual spec: < http: // nvlpubs . nist . gov / nistpubs / FIPS / NIST . FIPS . 180-4 . pdf >
* wikipedia's pseudocode breakdown: < https: // en . wikipedia . org / wiki / SHA-2 # Pseudocode >
* a JS implementation that helped as I was debugging some boneheaded mistakes: < http: // www . movable-type . co . uk / scripts / sha256 . html >
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* slides of a talk explaining the steps < https: // speakerd . s3 . amazonaws . com / presentations / c7c8df2206074d83b3d18fcba3287328 / slides . pdf >
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## Tests
`shamwow_test.rb` contains a few sanity tests for the bit-rotation functions and for the hashes themselves, testing against the output of the `Digest` gem in the standard library.
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## Obligatory
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[](https://www.youtube.com/watch?v=F3lrhPeK6gU)
