Class: CryptoToolchain::Utilities::MD4

Inherits:
Object
  • Object
show all
Defined in:
lib/crypto_toolchain/utilities/md4.rb

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(message) ⇒ MD4

Returns a new instance of MD4.



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# File 'lib/crypto_toolchain/utilities/md4.rb', line 21

def initialize(message)
  @original = message
end

Class Method Details

.bindigest(str, state: INITIAL_STATE, append_length: 0) ⇒ Object 



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# File 'lib/crypto_toolchain/utilities/md4.rb', line 10

def bindigest(str, state: INITIAL_STATE, append_length: 0)
  CryptoToolchain::Utilities::MD4.new(str).bindigest(state: state, append_length: append_length)
end

.digest ⇒ Object 



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# File 'lib/crypto_toolchain/utilities/md4.rb', line 13

def bindigest(str, state: INITIAL_STATE, append_length: 0)
  CryptoToolchain::Utilities::MD4.new(str).bindigest(state: state, append_length: append_length)
end

.hexdigest(str, state: INITIAL_STATE, append_length: 0) ⇒ Object 



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# File 'lib/crypto_toolchain/utilities/md4.rb', line 6

def hexdigest(str, state: INITIAL_STATE, append_length: 0 )
  CryptoToolchain::Utilities::MD4.new(str).hexdigest(state: state, append_length: append_length)
end

.padding(str) ⇒ Object 



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# File 'lib/crypto_toolchain/utilities/md4.rb', line 15

def padding(str)
  num_null_pad = (56 - (str.bytesize + 1) ) % 64
  0x80.chr + (0.chr * num_null_pad) + [(str.bytesize * 8)].pack("Q<")
end

Instance Method Details

#bindigest(state: INITIAL_STATE, append_length: 0) ⇒ Object Also known as: digest 



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# File 'lib/crypto_toolchain/utilities/md4.rb', line 29

def bindigest(state: INITIAL_STATE, append_length: 0)
  running_state = registers_from(state)

  length = original.bytesize + append_length

  padding_len = (56 - (length + 1) ) % 64
  str_length = [(length * 8)].pack("Q<")
  padding = (0x80.chr + (0.chr * padding_len) + str_length)

  (original + padding).in_blocks(64).each do |block|
    w = block.unpack("L<16")

    a, b, c, d = running_state
    # Extraction of each 16-operation round into a loop over four elements originally
    # found at https://rosettacode.org/wiki/MD4#Ruby
    [0, 4, 8, 12].each do |i|
      a = f(a, b, c, d, w[i]).lrot(3)
      d = f(d, a, b, c, w[i+1]).lrot(7)
      c = f(c, d, a, b, w[i+2]).lrot(11)
      b = f(b, c, d, a, w[i+3]).lrot(19)
    end
    [0, 1, 2, 3].each do |i|
      a = g(a, b, c, d, w[i]).lrot(3)
      d = g(d, a, b, c, w[i+4]).lrot(5)
      c = g(c, d, a, b, w[i+8]).lrot(9)
      b = g(b, c, d, a, w[i+12]).lrot(13)
    end
    [0, 2, 1, 3].each do |i|
      a = h(a, b, c, d, w[i]).lrot(3)
      d = h(d, a, b, c, w[i+8]).lrot(9)
      c = h(c, d, a, b, w[i+4]).lrot(11)
      b = h(b, c, d, a, w[i+12]).lrot(15)
    end

    [a, b, c, d].each_with_index do |val, i|
      running_state[i] = (running_state[i] + val) & 0xffffffff
    end
  end

  running_state.pack("L<4")
end

#hexdigest(state: INITIAL_STATE, append_length: 0) ⇒ Object 



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# File 'lib/crypto_toolchain/utilities/md4.rb', line 25

def hexdigest(state: INITIAL_STATE, append_length: 0)
  bindigest(state: state, append_length: append_length).unpack("H*").join
end