Module: Bitcoin::Util

Included in:
Bitcoin, Message::Base, Message::Base, Wallet::MasterKey, Wallet::MasterKey
Defined in:
lib/bitcoin/util.rb

Overview

bitcoin utility. following methods can be used as follows.

Bitcoin.pack_var_int(5)

Constant Summary collapse

DIGEST_NAME_SHA256 = 
'sha256'

Instance Method Summary collapse

Instance Method Details

#byte_to_bit(byte) ⇒ Object

byte convert to the sequence of bits packed eight in a byte with the least significant bit first.



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# File 'lib/bitcoin/util.rb', line 81

def byte_to_bit(byte)
  byte.unpack('b*').first
end

#calc_checksum(hex) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 112

def calc_checksum(hex)
  double_sha256(hex.htb).bth[0..7]
end

#decode_base58_address(addr) ⇒ Array

decode Base58 check encoding address.

Parameters:

Returns:

  • (Array) —

    hex and address version



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# File 'lib/bitcoin/util.rb', line 102

def decode_base58_address(addr)
  hex = Base58.decode(addr)
  if hex.size == 50 && calc_checksum(hex[0...-8]) == hex[-8..-1]
    raise 'Invalid version bytes.' unless [Bitcoin.chain_params.address_version, Bitcoin.chain_params.p2sh_version].include?(hex[0..1])
    [hex[2...-8], hex[0..1]]
  else
    raise 'Invalid address.'
  end
end

#double_sha256(payload) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 76

def double_sha256(payload)
  sha256(sha256(payload))
end

#encode_base58_address(hex, addr_version) ⇒ String

encode Base58 check address.

Parameters:

  • hex (String) —

    the address payload.

  • addr_version (String) —

    the address version for P2PKH and P2SH.

Returns:

  • (String) —

    Base58 check encoding address.



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# File 'lib/bitcoin/util.rb', line 94

def encode_base58_address(hex, addr_version)
  base = addr_version + hex
  Base58.encode(base + calc_checksum(base))
end

#hash160(hex) ⇒ Object

generate sha256-ripemd160 hash for value



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# File 'lib/bitcoin/util.rb', line 86

def hash160(hex)
  Digest::RMD160.hexdigest(Digest::SHA256.digest(hex.htb))
end

#hmac_sha256(key, data) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 118

def hmac_sha256(key, data)
  OpenSSL::HMAC.digest(DIGEST_NAME_SHA256, key, data)
end

#pack_boolean(b) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 63

def pack_boolean(b)
  b ? [0xFF].pack('C') : [0x00].pack('C')
end

#pack_var_int(i) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 20

def pack_var_int(i)
  if i <  0xfd
    [i].pack('C')
  elsif i <= 0xffff
    [0xfd, i].pack('Cv')
  elsif i <= 0xffffffff
    [0xfe, i].pack('CV')
  elsif i <= 0xffffffffffffffff
    [0xff, i].pack('CQ')
  else
    raise "int(#{i}) too large!"
  end
end

#pack_var_string(payload) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 11

def pack_var_string(payload)
  pack_var_int(payload.bytesize) + payload
end

#sha256(payload) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 72

def sha256(payload)
  Digest::SHA256.digest(payload)
end

#unpack_boolean(payload) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 67

def unpack_boolean(payload)
  data, payload = payload.unpack('Ca*')
  [(data.zero? ? false : true), payload]
end

#unpack_var_int(payload) ⇒ Object

Returns an integer for a valid payload, otherwise nil.

Returns:

  • an integer for a valid payload, otherwise nil



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# File 'lib/bitcoin/util.rb', line 35

def unpack_var_int(payload)
  case payload.unpack('C').first
  when 0xfd
    payload.unpack('xva*')
  when 0xfe
    payload.unpack('xVa*')
  when 0xff
    payload.unpack('xQa*')
  else
    payload.unpack('Ca*')
  end
end

#unpack_var_int_from_io(buf) ⇒ Object

Returns an integer for a valid payload, otherwise nil.

Returns:

  • an integer for a valid payload, otherwise nil



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# File 'lib/bitcoin/util.rb', line 49

def unpack_var_int_from_io(buf)
  uchar = buf.read(1)&.unpack('C')&.first
  case uchar
  when 0xfd
    buf.read(2)&.unpack('v')&.first
  when 0xfe
    buf.read(4)&.unpack('V')&.first
  when 0xff
    buf.read(8)&.unpack('Q')&.first
  else
    uchar
  end
end

#unpack_var_string(payload) ⇒ Object 



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# File 'lib/bitcoin/util.rb', line 15

def unpack_var_string(payload)
  size, payload = unpack_var_int(payload)
  size > 0 ? payload.unpack("a#{size}a*") : [nil, payload]
end