зеркало из https://github.com/github/ruby.git
72 строки
2.2 KiB
Ruby
72 строки
2.2 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
# This code was extracted from https://github.com/Solistra/ruby-digest which is under public domain
|
|
module Bundler
|
|
module Digest
|
|
# The initial constant values for the 32-bit constant words A, B, C, D, and
|
|
# E, respectively.
|
|
SHA1_WORDS = [0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476, 0xC3D2E1F0].freeze
|
|
|
|
# The 8-bit field used for bitwise `AND` masking. Defaults to `0xFFFFFFFF`.
|
|
SHA1_MASK = 0xFFFFFFFF
|
|
|
|
class << self
|
|
def sha1(string)
|
|
unless string.is_a?(String)
|
|
raise TypeError, "can't convert #{string.class.inspect} into String"
|
|
end
|
|
|
|
buffer = string.b
|
|
|
|
words = SHA1_WORDS.dup
|
|
generate_split_buffer(buffer) do |chunk|
|
|
w = []
|
|
chunk.each_slice(4) do |a, b, c, d|
|
|
w << (((a << 8 | b) << 8 | c) << 8 | d)
|
|
end
|
|
a, b, c, d, e = *words
|
|
(16..79).each do |i|
|
|
w[i] = SHA1_MASK & rotate((w[i-3] ^ w[i-8] ^ w[i-14] ^ w[i-16]), 1)
|
|
end
|
|
0.upto(79) do |i|
|
|
case i
|
|
when 0..19
|
|
f = ((b & c) | (~b & d))
|
|
k = 0x5A827999
|
|
when 20..39
|
|
f = (b ^ c ^ d)
|
|
k = 0x6ED9EBA1
|
|
when 40..59
|
|
f = ((b & c) | (b & d) | (c & d))
|
|
k = 0x8F1BBCDC
|
|
when 60..79
|
|
f = (b ^ c ^ d)
|
|
k = 0xCA62C1D6
|
|
end
|
|
t = SHA1_MASK & (SHA1_MASK & rotate(a, 5) + f + e + k + w[i])
|
|
a, b, c, d, e = t, a, SHA1_MASK & rotate(b, 30), c, d # rubocop:disable Style/ParallelAssignment
|
|
end
|
|
mutated = [a, b, c, d, e]
|
|
words.map!.with_index {|word, index| SHA1_MASK & (word + mutated[index]) }
|
|
end
|
|
|
|
words.pack("N*").unpack("H*").first
|
|
end
|
|
|
|
private
|
|
|
|
def generate_split_buffer(string, &block)
|
|
size = string.bytesize * 8
|
|
buffer = string.bytes << 128
|
|
buffer << 0 while buffer.size % 64 != 56
|
|
buffer.concat([size].pack("Q>").bytes)
|
|
buffer.each_slice(64, &block)
|
|
end
|
|
|
|
def rotate(value, spaces)
|
|
value << spaces | value >> (32 - spaces)
|
|
end
|
|
end
|
|
end
|
|
end
|