Merge #17: Add Ruby implementation

a06fd77 Add usage document (azuchi)
88204c7 Remove unnecessary code (azuchi)
8e988e7 Add script pubkey parse logic to SegiwtAddr#scriptpubkey= (azuchi)
30d8816 Add encoded value check (azuchi)
590d898 Fix check data length logic (azuchi)
1274ee7 Add newline at end of file (azuchi)
8795117 Add Ruby implementation (azuchi)

Tree-SHA512: 3d60d8d749335bfeffe248e16d7cf4dad88d7f86d0207246c8e57d91472ffe74001759d6b333a2f9afc2b1ac8a1dc31d9834ec2b7572d43a0edb30ebabdcbabe

ref/ruby/README.md

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+# Bech32 Ruby
+
+## Usage
+
+Require code:
+
+```ruby
+require './bech32'
+require './segwit_addr'
+```
+
+### Decode
+
+Decode Bech32-encoded data into hrp part and data part.
+
+```ruby
+hrp, data = Bech32.decode('BC1QW508D6QEJXTDG4Y5R3ZARVARY0C5XW7KV8F3T4')
+
+# hrp is human-readable part of Bech32 format
+'bc'
+
+# data is data part of Bech32 format
+[0, 14, 20, 15, 7, 13, 26, 0, 25, 18, 6, 11, 13, 8, 21, 4, 20, 3, 17, 2, 29, 3, 12, 29, 3, 4, 15, 24, 20, 6, 14, 30, 22]
+```
+
+Decode Bech32-encoded Segwit address into `SegwitAddr` instance.
+
+```ruby
+addr = 'BC1QW508D6QEJXTDG4Y5R3ZARVARY0C5XW7KV8F3T4'
+segwit_addr = SegwitAddr.new(addr)
+
+# generate script pubkey
+segwit_addr.to_script_pubkey
+=> 0014751e76e8199196d454941c45d1b3a323f1433bd6
+```
+
+### Encode
+
+Encode Bech32 human-readable part and data part into Bech32 string.
+
+```ruby
+hrp = 'bc'
+data = [0, 14, 20, 15, 7, 13, 26, 0, 25, 18, 6, 11, 13, 8, 21, 4, 20, 3, 17, 2, 29, 3, 12, 29, 3, 4, 15, 24, 20, 6, 14, 30, 22]
+
+bech = Bech32.encode(hrp, data)
+=> bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4
+```
+
+Encode Segwit script into Bech32 Segwit address.
+
+```ruby
+segwit_addr = SegwitAddr.new
+segwit_addr.hrp = 'bc'
+segwit_addr.scriptpubkey = '0014751e76e8199196d454941c45d1b3a323f1433bd6'
+
+# generate addr
+segwit_addr.addr
+=> bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4
+```
+
+## Test
+
+Run test with:
+
+    $ ruby test_bech32.rb

ref/ruby/bech32.rb

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+# Copyright (c) 2017 Shigeyuki Azuchi
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+module Bech32
+
+  SEPARATOR = '1'
+
+  CHARSET = %w(q p z r y 9 x 8 g f 2 t v d w 0 s 3 j n 5 4 k h c e 6 m u a 7 l)
+
+  module_function
+
+  # Encode Bech32 string
+  def encode(hrp, data)
+    checksummed = data + create_checksum(hrp, data)
+    hrp + SEPARATOR + checksummed.map{|i|CHARSET[i]}.join
+  end
+
+  # Decode a Bech32 string and determine hrp and data
+  def decode(bech)
+    # check uppercase/lowercase
+    return nil if (bech.downcase != bech && bech.upcase != bech)
+    bech.each_char{|c|return nil if c.ord < 33 || c.ord > 126}
+    bech = bech.downcase
+    # check data length
+    pos = bech.rindex(SEPARATOR)
+    return nil if pos.nil? || pos < 1 || pos + 7 > bech.length || bech.length > 90
+    # check valid charset
+    bech[pos+1..-1].each_char{|c|return nil unless CHARSET.include?(c)}
+    # split hrp and data
+    hrp = bech[0..pos-1]
+    data = bech[pos+1..-1].each_char.map{|c|CHARSET.index(c)}
+    # check checksum
+    return nil unless verify_checksum(hrp, data)
+    [hrp, data[0..-7]]
+  end
+
+  # Compute the checksum values given hrp and data.
+  def create_checksum(hrp, data)
+    values = expand_hrp(hrp) + data
+    polymod = polymod(values + [0, 0, 0, 0, 0, 0]) ^ 1
+    (0..5).map{|i|(polymod >> 5 * (5 - i)) & 31}
+  end
+
+  # Verify a checksum given Bech32 string
+  def verify_checksum(hrp, data)
+    polymod(expand_hrp(hrp) + data) == 1
+  end
+
+  # Expand the hrp into values for checksum computation.
+  def expand_hrp(hrp)
+    hrp.each_char.map{|c|c.ord >> 5} + [0] + hrp.each_char.map{|c|c.ord & 31}
+  end
+
+  # Compute Bech32 checksum
+  def polymod(values)
+    generator = [0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3]
+    chk = 1
+    values.each do |v|
+      top = chk >> 25
+      chk = (chk & 0x1ffffff) << 5 ^ v
+      (0..4).each{|i|chk ^= ((top >> i) & 1) == 0 ? 0 : generator[i]}
+    end
+    chk
+  end
+
+  private_class_method :polymod, :expand_hrp
+
+end

ref/ruby/segwit_addr.rb

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+# Copyright (c) 2017 Shigeyuki Azuchi
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+require './bech32'
+
+class SegwitAddr
+
+  attr_accessor :hrp # human-readable part
+  attr_accessor :ver # witness version
+  attr_accessor :prog # witness program
+
+  def initialize(addr = nil)
+    @hrp, @ver, @prog = parse_addr(addr) if addr
+  end
+
+  def to_scriptpubkey
+    v = ver == 0 ? ver : ver + 0x80
+    ([v, prog.length].pack("CC") + prog.map{|p|[p].pack("C")}.join).unpack('H*').first
+  end
+
+  def scriptpubkey=(script)
+    values = [script].pack('H*').unpack("C*")
+    @ver = values[0]
+    @prog = values[2..-1]
+  end
+
+  def addr
+    encoded = Bech32.encode(hrp, [ver] + convert_bits(prog, 8, 5))
+    chrp, cver, cprog = parse_addr(encoded)
+    raise 'Invalid address' if chrp != hrp || cver != ver || cprog != prog
+    encoded
+  end
+
+  private
+
+  def parse_addr(addr)
+    hrp, data = Bech32.decode(addr)
+    raise 'Invalid address.' if hrp.nil? || (hrp != 'bc' && hrp != 'tb')
+    ver = data[0]
+    raise 'Invalid witness version' if ver > 16
+    prog = convert_bits(data[1..-1], 5, 8, false)
+    raise 'Invalid witness program' if prog.nil? || prog.length < 2 || prog.length > 40
+    raise 'Invalid witness program with version 0' if ver == 0 && (prog.length != 20 && prog.length != 32)
+    [hrp, ver, prog]
+  end
+
+  def convert_bits(data, from, to, padding=true)
+    acc = 0
+    bits = 0
+    ret = []
+    maxv = (1 << to) - 1
+    max_acc = (1 << (from + to - 1)) - 1
+    data.each do |v|
+      return nil if v < 0 || (v >> from) != 0
+      acc = ((acc << from) | v) & max_acc
+      bits += from
+      while bits >= to
+        bits -= to
+        ret << ((acc >> bits) & maxv)
+      end
+    end
+    if padding
+      ret << ((acc << (to - bits)) & maxv) unless bits == 0
+    elsif bits >= from || ((acc << (to - bits)) & maxv) != 0
+      return nil
+    end
+    ret
+  end
+
+end

ref/ruby/test_bech32.rb

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+# Copyright (c) 2017 Shigeyuki Azuchi
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+require './bech32'
+require './segwit_addr'
+require 'test/unit'
+
+class TestBech32 < Test::Unit::TestCase
+
+  VALID_CHECKSUM = [
+      "A12UEL5L",
+      "an83characterlonghumanreadablepartthatcontainsthenumber1andtheexcludedcharactersbio1tt5tgs",
+      "abcdef1qpzry9x8gf2tvdw0s3jn54khce6mua7lmqqqxw",
+      "11qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqc8247j",
+      "split1checkupstagehandshakeupstreamerranterredcaperred2y9e3w",
+  ]
+
+  VALID_ADDRESS = [
+      ["BC1QW508D6QEJXTDG4Y5R3ZARVARY0C5XW7KV8F3T4", "0014751e76e8199196d454941c45d1b3a323f1433bd6"],
+      ["tb1qrp33g0q5c5txsp9arysrx4k6zdkfs4nce4xj0gdcccefvpysxf3q0sl5k7",
+       "00201863143c14c5166804bd19203356da136c985678cd4d27a1b8c6329604903262"],
+      ["bc1pw508d6qejxtdg4y5r3zarvary0c5xw7kw508d6qejxtdg4y5r3zarvary0c5xw7k7grplx",
+       "8128751e76e8199196d454941c45d1b3a323f1433bd6751e76e8199196d454941c45d1b3a323f1433bd6"],
+      ["BC1SW50QA3JX3S", "9002751e"],
+      ["bc1zw508d6qejxtdg4y5r3zarvaryvg6kdaj", "8210751e76e8199196d454941c45d1b3a323"],
+      ["tb1qqqqqp399et2xygdj5xreqhjjvcmzhxw4aywxecjdzew6hylgvsesrxh6hy",
+       "0020000000c4a5cad46221b2a187905e5266362b99d5e91c6ce24d165dab93e86433"],
+  ]
+
+  INVALID_ADDRESS = [
+      "tc1qw508d6qejxtdg4y5r3zarvary0c5xw7kg3g4ty",
+      "bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t5",
+      "BC13W508D6QEJXTDG4Y5R3ZARVARY0C5XW7KN40WF2",
+      "bc1rw5uspcuh",
+      "bc10w508d6qejxtdg4y5r3zarvary0c5xw7kw508d6qejxtdg4y5r3zarvary0c5xw7kw5rljs90",
+      "BC1QR508D6QEJXTDG4Y5R3ZARVARYV98GJ9P",
+      "tb1qrp33g0q5c5txsp9arysrx4k6zdkfs4nce4xj0gdcccefvpysxf3q0sL5k7",
+      "tb1pw508d6qejxtdg4y5r3zarqfsj6c3",
+      "tb1qrp33g0q5c5txsp9arysrx4k6zdkfs4nce4xj0gdcccefvpysxf3pjxtptv",
+  ]
+
+  def test_verify_checksum
+    VALID_CHECKSUM.each do |bech|
+      hrp, _ = Bech32.decode(bech)
+      assert_not_nil (hrp)
+      pos = bech.rindex('1')
+      bech = bech[0..pos] + (bech[pos + 1].ord ^ 1).chr + bech[pos+2..-1]
+      hrp, _ = Bech32.decode(bech)
+      assert_nil (hrp)
+    end
+  end
+
+  def test_valid_address
+    VALID_ADDRESS.each do |addr, hex|
+      segwit_addr = SegwitAddr.new(addr)
+      assert_not_nil(segwit_addr.ver)
+      assert_equal(hex, segwit_addr.to_scriptpubkey)
+      assert_equal(addr.downcase, segwit_addr.addr)
+    end
+  end
+
+  def test_invalid_address
+    INVALID_ADDRESS.each do |addr|
+      assert_raise(RuntimeError){SegwitAddr.new(addr)}
+    end
+  end
+
+  def test_scriptpubkey=
+    segwit_addr = SegwitAddr.new
+    segwit_addr.hrp = 'bc'
+    segwit_addr.scriptpubkey = '0014751e76e8199196d454941c45d1b3a323f1433bd6'
+    assert_equal('bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4', segwit_addr.addr)
+  end
+
+end