Class: Tapyrus::Key

Inherits:
Object
  • Object
show all
Defined in:
lib/tapyrus/key.rb

Overview

tapyrus key class

Constant Summary collapse

PUBLIC_KEY_SIZE = 
65
COMPRESSED_PUBLIC_KEY_SIZE = 
33
SIGNATURE_SIZE = 
72
COMPACT_SIGNATURE_SIZE = 
65
SIG_ALGO = 
[:ecdsa, :schnorr]
TYPES = 
{ uncompressed: 0x00, compressed: 0x01, p2pkh: 0x10, p2wpkh: 0x11, p2wpkh_p2sh: 0x12 }
MIN_PRIV_KEY_MOD_ORDER = 
0x01
MAX_PRIV_KEY_MOD_ORDER =

Order of secp256k1’s generator minus 1.

ECDSA::Group::Secp256k1.order - 1

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(priv_key: nil, pubkey: nil, key_type: nil, compressed: true, allow_hybrid: false) ⇒ Tapyrus::Key

initialize private key

Raises:

  • (ArgumentError) 


32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
 
# File 'lib/tapyrus/key.rb', line 32

def initialize(priv_key: nil, pubkey: nil, key_type: nil, compressed: true, allow_hybrid: false)
  if key_type.nil? && !compressed.nil? && pubkey.nil?
    warn('Use key_type parameter instead of compressed. compressed parameter removed in the future.')
  end
  if key_type
    @key_type = key_type
    compressed = @key_type != TYPES[:uncompressed]
  else
    @key_type = compressed ? TYPES[:compressed] : TYPES[:uncompressed]
  end
  @secp256k1_module = Tapyrus.secp_impl
  @priv_key = priv_key
  raise ArgumentError, Errors::Messages::INVALID_PRIV_KEY unless validate_private_key_range(@priv_key) if @priv_key
  if pubkey
    @pubkey = pubkey
  else
    @pubkey = generate_pubkey(priv_key, compressed: compressed) if priv_key
  end
  raise ArgumentError, Errors::Messages::INVALID_PUBLIC_KEY unless fully_valid_pubkey?(allow_hybrid)
end

Instance Attribute Details

#key_type ⇒ Object

Returns the value of attribute key_type.



16
17
18
 
# File 'lib/tapyrus/key.rb', line 16

def key_type
  @key_type
end

#priv_key ⇒ Object

Returns the value of attribute priv_key.



14
15
16
 
# File 'lib/tapyrus/key.rb', line 14

def priv_key
  @priv_key
end

#pubkey ⇒ Object

Returns the value of attribute pubkey.



15
16
17
 
# File 'lib/tapyrus/key.rb', line 15

def pubkey
  @pubkey
end

#secp256k1_module ⇒ Object (readonly)

Returns the value of attribute secp256k1_module.



17
18
19
 
# File 'lib/tapyrus/key.rb', line 17

def secp256k1_module
  @secp256k1_module
end

Class Method Details

.compress_or_uncompress_pubkey?(pubkey) ⇒ Boolean

check pubkey (hex) is compress or uncompress pubkey.



150
151
152
153
154
155
156
157
158
159
160
161
162
 
# File 'lib/tapyrus/key.rb', line 150

def self.compress_or_uncompress_pubkey?(pubkey)
  p = pubkey.htb
  return false if p.bytesize < COMPRESSED_PUBLIC_KEY_SIZE
  case p[0]
  when "\x04"
    return false unless p.bytesize == PUBLIC_KEY_SIZE
  when "\x02", "\x03"
    return false unless p.bytesize == COMPRESSED_PUBLIC_KEY_SIZE
  else
    return false
  end
  true
end

.compress_pubkey?(pubkey) ⇒ Boolean

check pubkey (hex) is compress pubkey.



165
166
167
168
 
# File 'lib/tapyrus/key.rb', line 165

def self.compress_pubkey?(pubkey)
  p = pubkey.htb
  p.bytesize == COMPRESSED_PUBLIC_KEY_SIZE && ["\x02", "\x03"].include?(p[0])
end

.from_wif(wif) ⇒ Object

import private key from wif format en.bitcoin.it/wiki/Wallet_import_format

Raises:

  • (ArgumentError) 


61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
 
# File 'lib/tapyrus/key.rb', line 61

def self.from_wif(wif)
  hex = Base58.decode(wif)
  raise ArgumentError, 'data is too short' if hex.htb.bytesize < 4
  version = hex[0..1]
  data = hex[2...-8].htb
  checksum = hex[-8..-1]
  raise ArgumentError, 'invalid version' unless version == Tapyrus.chain_params.privkey_version
  unless Tapyrus.calc_checksum(version + data.bth) == checksum
    raise ArgumentError, Errors::Messages::INVALID_CHECKSUM
  end
  key_len = data.bytesize
  if key_len == COMPRESSED_PUBLIC_KEY_SIZE && data[-1].unpack('C').first == 1
    key_type = TYPES[:compressed]
    data = data[0..-2]
  elsif key_len == 32
    key_type = TYPES[:uncompressed]
  else
    raise ArgumentError, 'Wrong number of bytes for a private key, not 32 or 33'
  end
  new(priv_key: data.bth, key_type: key_type)
end

.generate(key_type = ) ⇒ Object

generate key pair



54
55
56
57
 
# File 'lib/tapyrus/key.rb', line 54

def self.generate(key_type = TYPES[:compressed])
  priv_key, pubkey = Tapyrus.secp_impl.generate_key_pair
  new(priv_key: priv_key, pubkey: pubkey, key_type: key_type)
end

.low_signature?(sig) ⇒ Boolean

check sig is low.



171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
 
# File 'lib/tapyrus/key.rb', line 171

def self.low_signature?(sig)
  s = sig.unpack('C*')
  len_r = s[3]
  len_s = s[5 + len_r]
  val_s = s.slice(6 + len_r, len_s)

  # prettier-ignore
  max_mod_half_order = [
      0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
      0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
      0x5d, 0x57, 0x6e, 0x73, 0x57, 0xa4, 0x50, 0x1d,
      0xdf, 0xe9, 0x2f, 0x46, 0x68, 0x1b, 0x20, 0xa0
  ]
  compare_big_endian(val_s, [0]) > 0 && compare_big_endian(val_s, max_mod_half_order) <= 0
end

.valid_signature_encoding?(sig, data_sig = false) ⇒ Boolean

check sig is correct der encoding. This function is consensus-critical since BIP66.



192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
 
# File 'lib/tapyrus/key.rb', line 192

def self.valid_signature_encoding?(sig, data_sig = false)
  num_parts = data_sig ? 8 : 9
  size = data_sig ? 72 : 73

  return false if sig.bytesize < num_parts || sig.bytesize > size # Minimum and maximum size check

  s = sig.unpack('C*')

  return false if s[0] != 0x30 || s[1] != s.size - (data_sig ? 2 : 3) # A signature is of type 0x30 (compound). Make sure the length covers the entire signature.

  len_r = s[3]
  return false if 5 + len_r >= s.size # Make sure the length of the S element is still inside the signature.

  len_s = s[5 + len_r]
  return false unless len_r + len_s + (data_sig ? 6 : 7) == s.size #Verify that the length of the signature matches the sum of the length of the elements.

  return false unless s[2] == 0x02 # Check whether the R element is an integer.

  return false if len_r == 0 # Zero-length integers are not allowed for R.

  return false unless s[4] & 0x80 == 0 # Negative numbers are not allowed for R.

  # Null bytes at the start of R are not allowed, unless R would otherwise be interpreted as a negative number.
  return false if len_r > 1 && (s[4] == 0x00) && (s[5] & 0x80 == 0)

  return false unless s[len_r + 4] == 0x02 # Check whether the S element is an integer.

  return false if len_s == 0 # Zero-length integers are not allowed for S.
  return false unless (s[len_r + 6] & 0x80) == 0 # Negative numbers are not allowed for S.

  # Null bytes at the start of S are not allowed, unless S would otherwise be interpreted as a negative number.
  return false if len_s > 1 && (s[len_r + 6] == 0x00) && (s[len_r + 7] & 0x80 == 0)

  true
end

Instance Method Details

#compressed? ⇒ Boolean 



137
138
139
 
# File 'lib/tapyrus/key.rb', line 137

def compressed?
  key_type != TYPES[:uncompressed]
end

#fully_valid_pubkey?(allow_hybrid = false) ⇒ Boolean

fully validate whether this is a valid public key (more expensive than IsValid())



229
230
231
 
# File 'lib/tapyrus/key.rb', line 229

def fully_valid_pubkey?(allow_hybrid = false)
  valid_pubkey? && secp256k1_module.parse_ec_pubkey?(pubkey, allow_hybrid)
end

#hash160 ⇒ Object

get hash160 public key.



127
128
129
 
# File 'lib/tapyrus/key.rb', line 127

def hash160
  Tapyrus.hash160(pubkey)
end

#sign(data, low_r = true, extra_entropy = nil, algo: :ecdsa) ⇒ String

sign data with private key

Raises:

  • (ArgumentError) 


98
99
100
101
102
103
104
105
106
107
108
 
# File 'lib/tapyrus/key.rb', line 98

def sign(data, low_r = true, extra_entropy = nil, algo: :ecdsa)
  raise ArgumentError, 'Unsupported algorithm has been specified.' unless SIG_ALGO.include?(algo)
  case algo
  when :ecdsa
    sign_ecdsa(data, low_r, extra_entropy)
  when :schnorr
    secp256k1_module.sign_data(data, priv_key, extra_entropy, algo: algo)
  else
    false
  end
end

#to_p2pkh ⇒ Object

Deprecated.

get pay to pubkey hash address



133
134
135
 
# File 'lib/tapyrus/key.rb', line 133

def to_p2pkh
  Tapyrus::Script.to_p2pkh(hash160).addresses.first
end

#to_point ⇒ ECDSA::Point

generate pubkey ec point



143
144
145
146
147
 
# File 'lib/tapyrus/key.rb', line 143

def to_point
  p = pubkey
  p ||= generate_pubkey(priv_key, compressed: compressed)
  ECDSA::Format::PointOctetString.decode(p.htb, Tapyrus::Secp256k1::GROUP)
end

#to_wif ⇒ Object

export private key with wif format



84
85
86
87
88
89
90
 
# File 'lib/tapyrus/key.rb', line 84

def to_wif
  version = Tapyrus.chain_params.privkey_version
  hex = version + priv_key
  hex += '01' if compressed?
  hex += Tapyrus.calc_checksum(hex)
  Base58.encode(hex)
end

#verify(sig, origin, algo: :ecdsa) ⇒ Boolean

verify signature using public key



115
116
117
118
119
120
121
122
123
124
 
# File 'lib/tapyrus/key.rb', line 115

def verify(sig, origin, algo: :ecdsa)
  return false unless valid_pubkey?
  begin
    raise ArgumentError, 'Unsupported algorithm has been specified.' unless SIG_ALGO.include?(algo)
    sig = ecdsa_signature_parse_der_lax(sig) if algo == :ecdsa
    secp256k1_module.verify_sig(origin, sig, pubkey, algo: algo)
  rescue Exception
    false
  end
end