Module: Bitcoin::Namecoin::Script

Defined in:
lib/bitcoin/namecoin.rb

Overview

Namecoin-specific Script methods for parsing and creating of namecoin scripts, as well as methods to extract address, name_hash, name and value.

Class Method Summary collapse

Class Method Details

.included(base) ⇒ Object 



27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
 
# File 'lib/bitcoin/namecoin.rb', line 27

def self.included(base)
  base.constants.each {|c| const_set(c, base.const_get(c)) unless constants.include?(c) }
  base.class_eval do

    # get the hash160 for this hash160, namecoin or pubkey script
    def get_hash160
      return @chunks[2..-3][0].unpack("H*")[0]  if is_hash160?
      return @chunks[-3].unpack("H*")[0]        if is_namecoin?
      return Bitcoin.hash160(get_pubkey)        if is_pubkey?
    end

    # get all addresses this script corresponds to (if possible)
    def get_addresses
      return [get_pubkey_address]    if is_pubkey?
      return [get_hash160_address]   if is_hash160? || is_namecoin?
      return get_multisig_addresses  if is_multisig?
    end

    # get type of this tx
    def type
      if is_name_new?;            :name_new
      elsif is_name_firstupdate?; :name_firstupdate
      elsif is_name_update?;      :name_update
      elsif is_hash160?;          :hash160
      elsif is_pubkey?;           :pubkey
      elsif is_multisig?;         :multisig
      elsif is_p2sh?;             :p2sh
      else;                       :unknown
      end
    end

    # is namecoin name_new script
    # OP_1 name_hash OP_2DROP <hash160_script>
    def is_name_new?
      return false  if @chunks.size < 8
      [-8, -6, -5, -4, -2, -1].map {|i| @chunks[i] } ==
        [OP_1, OP_2DROP, OP_DUP, OP_HASH160, OP_EQUALVERIFY, OP_CHECKSIG]
    end

    # is namecoin name_firstupdate script
    # OP_2 name rand value OP_2DROP OP_2DROP <hash160_script>
    def is_name_firstupdate?
      return false  if @chunks.size < 11
      [-11, -7, -6, -5, -4, -2, -1].map {|i| @chunks[i] } ==
        [82, OP_2DROP, OP_2DROP, OP_DUP, OP_HASH160, OP_EQUALVERIFY, OP_CHECKSIG]
    end

    # is namecoin name_update script
    # OP_3 name value OP_2DROP OP_DROP <hash160_script>
    def is_name_update?
      return false  if @chunks.size < 10
      [-10, -7, -6, -5, -4, -2, -1].map {|i| @chunks[i] } ==
        [83, OP_2DROP, OP_DROP, OP_DUP, OP_HASH160, OP_EQUALVERIFY, OP_CHECKSIG]
    end

    # is any kind of namecoin script
    def is_namecoin?
      is_name_new? || is_name_firstupdate? || is_name_update?
    end

    # get the name_hash of a namecoin name_new script
    def get_namecoin_hash
      return @chunks[-7].hth  if is_name_new?
      if is_name_firstupdate?
        name = @chunks[-10].to_s.hth
        rand = @chunks[-9].to_s.hth
        return Bitcoin.hash160(rand + name)
      end
    rescue
      nil
    end

    # get the name of a namecoin name_firstupdate or name_update script
    def get_namecoin_name
      return @chunks[-10]  if is_name_firstupdate?
      return @chunks[-9]  if is_name_update?
    end

    # get the value of a namecoin name_firstupdate or name_update script
    def get_namecoin_value
      @chunks[-8]  if is_name_firstupdate? || is_name_update?
    end

    # generate name_new tx for given +name+ and +address+.
    # the +caller+ should be the object that creates the script.
    # it gets the used random value passed to #set_rand.
    # OP_1 name_hash OP_2DROP <hash160_script>
    def self.to_name_new_script(caller, name, address)
      rand = rand(2**64).to_s(16).rjust(16, '0')
      name_hash = Bitcoin.hash160(rand + name.unpack("H*")[0])
      caller.set_rand rand # TODO: this is still ugly
      [ [ "51", "14",   name_hash, "6d" ].join ].pack("H*") + to_address_script(address)
    end

    # generate name_firstupdate tx for given +name+, +rand+, +value+ and +address+.
    # OP_2 name rand value OP_2DROP OP_2DROP <hash160_script>
    def self.to_name_firstupdate_script(name, rand, value, address)
      [ [ "52", name.bytesize.to_s(16).rjust(2, '0'), name.hth,
          rand.htb.bytesize.to_s(16).rjust(2, '0'), rand,
          value.bytesize.to_s(16).rjust(2, '0'), value.hth,
          "6d", "6d" ].join ].pack("H*") + to_address_script(address)
    end

    # generate name_update script for given +name+, +value+ and +address+.
    # OP_3 name value OP_2DROP OP_DROP <hash160_script>
    def self.to_name_update_script(name, value, address)
      [ [ "53", name.bytesize.to_s(16).rjust(2, '0'), name.hth,
          value.bytesize.to_s(16).rjust(2, '0'), value.hth,
          "6d", "75" ].join ].pack("H*") + to_address_script(address)
    end

  end
end