This project is no longer maintained and has been archived.
A simple Multihash implementation for ruby.
A multihash is a digest with an embedded hash function code (and length) ('cause you never know). It was developed primarily for use with IPFS, but is not specific to it.
Add this line to your application's Gemfile:
gem 'multihashes'And then execute:
$ bundle
Or install it yourself as:
$ gem install multihashes
This is a low-level library. Bring your own digest. A binary digest goes in, a binary digest goes out. To compute a sha256 multihash that would work nicely with IPFS:
require 'multihashes'
require 'digest'
digest = Digest::SHA256.digest 'Dade Murphy will never figure this one out'
multihash_binary_string = Multihashes.encode digest, 'sha2-256'
multihash_binary_string.unpack('H*').first # hex: "1220142711d38ca7a33c521841..."
out = Multihashes.decode multihash_binary_string
# => {:code=>18, :hash_function=>"sha2-256", :length=>32, :digest=>"\x14'\x11\xD3\x8C\xA7\xA3<R\x18Ao\x8F\xFC\xC6FH\xCAF\x16\xA6%\xB5\xE0\xA0\xAB=\xA1\x91\x1D]z"}Hash function names (latest is here, current multicodec is here)
| code | name | comment |
|---|---|---|
| 0x00 | identity | raw binary |
| 0x11 | sha1 | |
| 0x12 | sha2-256 | |
| 0x13 | sha2-512 | |
| 0x14 | sha3-512 | |
| 0x15 | sha3-384 | |
| 0x16 | sha3-256 | |
| 0x17 | sha3-224 | |
| 0x18 | shake-128 | |
| 0x19 | shake-256 | |
| 0x1a | keccak-224 | keccak has variable output length. The number specifies the core length |
| 0x1b | keccak-256 | |
| 0x1c | keccak-384 | |
| 0x1d | keccak-512 | |
| 0x22 | murmur3-128 | |
| 0x23 | murmur3-32 | |
| 0x56 | dbl-sha2-256 | |
| 0xd4 | md4 | |
| 0xd4 | md5 | |
| 0xd6 | bmt | Binary Merkle Tree Hash |
| 0x1100 | x11 | |
| 0xb201 | blake2b-8 | blake2b consists of 64 output lengths that give different hashes |
| 0xb202 | blake2b-16 | |
| 0xb203 | blake2b-24 | |
| ... | ||
| 0xb23f | blake2b-504 | |
| 0xb240 | blake2b-512 | |
| 0xb241 | blake2s-8 | blake2s consists of 32 output lengths that give different hashes |
| 0xb242 | blake2s-16 | |
| 0xb243 | blake2s-24 | |
| ... | ||
| 0xb25f | blake2s-248 | |
| 0xb260 | blake2s-256 | |
| 0xb301 | skein256-8 | skein256 consists of 32 output lengths that give different hashes |
| 0xb302 | skein256-16 | |
| 0xb303 | skein256-24 | |
| ... | ||
| 0xb31f | skein256-248 | |
| 0xb320 | skein256-256 | |
| 0xb321 | skein512-8 | skein256 consists of 32 output lengths that give different hashes |
| 0xb322 | skein512-16 | |
| 0xb323 | skein512-24 | |
| ... | ||
| 0xb35f | skein512-504 | |
| 0xb360 | skein512-512 | |
| 0xb361 | skein1024-8 | skein1024 consists of 128 output lengths that give different hashes |
| 0xb362 | skein1024-16 | |
| 0xb363 | skein1024-24 | |
| ... | ||
| 0xb3df | skein1024-1016 | |
| 0xb3e0 | skein1024-1024 |
After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install.
Bug reports and pull requests are welcome on GitHub at https://github.com/multiformats/ruby-multihash.
Check out our contributing document for more information on how we work, and about contributing in general. Please be aware that all interactions related to multiformats are subject to the IPFS Code of Conduct.
Small note: If editing the README, please conform to the standard-readme specification.
The gem is available as open source under the terms of the MIT License © 2015 Kyle Drake.