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Show HN: I made a C program to create a vanity SHA-1 hash for a text file
- keepamovin 2y agoAfter experimenting with cycling punctuation, and random capitalization I hit on the idea to use each word as a bit and map the original version of the word to 0 and the title-case-toggled version of the word to 1. Then just use the text file as a "counter nonce" and count from 0 until we find a counter that hashes to the vanity prefix we want. The advantage of this is flipping the capitalization of the first letter of each word doesn't drastically alter the visual appearance of the file (tho it may alter semantics!), and you get an easy to understand amount of entropy (number of states) to walk through. The C version linked only supports counting up to ~4 billion but it could be easily extended. A JS version using BigInt can go unlimited. For reference the included example text took a surprising 2 billion iterations to discover the correct 8 digit hash which is about what you'd expect from random (i.e., half the state space of 16*8 = (2*4)*8)
- saulpw 2y agoCool! I made a multithreaded version about 10 years that works for binary files like .zip files: https://github.com/century-arcade/src/tree/master/tools/vainhash https://github.com/century-arcade/src/tree/master/tools/vain...
- keepamovin 2y agoCool! How do you handle internal checks in the files? How does overwriting 8 zeroes not break stuff?
- saulpw 2y agoWell it was intended/used to fill out a .zip file comment section, so those 8 zeroes were ignored anyway.
- keepamovin 2y agoSmart!
- susam 2y agoThe SHA-256 hash of this sentence begins with 0573e7473.
- akoboldfrying 2y agoThe SHA-256 hash of this sentence does not.
- xeckr 2y agoNice one.
- keepamovin 2y agoOK, that's a cool way to fuzz the digest rather than the text :)
- orphea 2y agoThe SHA256 for this sentence begins with: one, eight, two, a, seven, c and nine.
- tmountain 2y agoOh boy, here we go…
- keepamovin 2y agoThat's a fun way to do it! :)
- ranger_danger 2y ago[flagged]
- kazinator 2y agoDon't bother applying here if your github doesn't look like this: $ git log --oneline deadbeef5 (HEAD -> master): Revised documentation of frobozz widget. 0cafef00d scrot_compress: fixed rare recursion case. 5ca1ab1e1 image_convolve: use thread pool for better performance.
- actinium226 2y agoI don't get the last one?
- deleted 2y ago[deleted]
- ruffrey 2y ago"scalable"
- TZubiri 2y agoThis is cute but it works in the opposite for me, looks very unprofessional and gives the impression you get distracted with nerdy internals instead of building product.
- fyrn_ 2y agoOn the other hand, where I work we want people like that. Not every place is a CRUD slop shop with joined at the hip SPA that needs more meat for the ginder. Research and specialized optimization roles exist
- coolThingsFirst 2y agowhat?
- frutiger 2y agoRead the commit sha prefixes as English
- 2y ago
- coolThingsFirst 2y agoInteresting, also this quote is as interesting as the code: "Your job, throughout your entire life, is to disappoint as many people as it takes to avoid disappointing yourself."
- metadat 2y agoThat took a second to process and sink in. Added to my shameful, neurotic HN profile.. haha, thank you!