Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Segwit implementation #26

Open
wants to merge 2 commits into
base: master
Choose a base branch
from
Open

Segwit implementation #26

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
c879e78
Implement segwit transaction serialization
mgpnd Dec 16, 2017
fa655da
Merge pull request #25 from mgpnd/SegWit
oleganza Jan 2, 2018
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
79 changes: 79 additions & 0 deletions lib/btcruby/segwit_transaction.rb
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,79 @@
module BTC
class SegwitTransaction < Transaction
def witness
inputs.reduce(''.b) do |serialized, txin|
serialized << BTC::WireFormat.encode_array(txin.witness) { |data| BTC::WireFormat.encode_string(data) }
end
end

def data
data = "".b
data << BTC::WireFormat.encode_int32le(self.version)
data << BTC::WireFormat.encode_uint8(0x00) # marker
data << BTC::WireFormat.encode_uint8(0x01) # flag
data << BTC::WireFormat.encode_varint(self.inputs.size)
self.inputs.each do |txin|
data << txin.data
end
data << BTC::WireFormat.encode_varint(self.outputs.size)
self.outputs.each do |txout|
data << txout.data
end
data << self.witness
data << BTC::WireFormat.encode_uint32le(lock_time)
data
end

# Calculate version 0 witness compatible digest as defined in BIP-143
def signature_hash(input_index: nil, output_script: nil, hash_type: BTC::SIGHASH_ALL, amount: 0)
raise ArgumentError, "Should specify input_index in Transaction#signature_hash." if !input_index
raise ArgumentError, "Should specify output_script in Transaction#signature_hash." if !output_script
raise ArgumentError, "Should specify hash_type in Transaction#signature_hash." if !hash_type

hash_prevouts = 0
hash_sequence = 0
hash_outputs = 0
tx = self.dup

if (hash_type & BTC::SIGHASH_ANYONECANPAY) == 0
serialized_prevouts = ''.b
tx.inputs.each do |txin|
serialized_prevouts << txin.outpoint.data
end
hash_prevouts = BTC.sha256(BTC.sha256(serialized_prevouts))
end

if (hash_type & BTC::SIGHASH_ANYONECANPAY) == 0 && (hash_type & SIGHASH_OUTPUT_MASK) != BTC::SIGHASH_SINGLE && (hash_type & SIGHASH_OUTPUT_MASK) != BTC::SIGHASH_NONE
serialized_sequence = ''.b
tx.inputs.each do |txin|
serialized_sequence << BTC::WireFormat.encode_uint32le(txin.sequence)
end
hash_sequence = BTC.sha256(BTC.sha256(serialized_sequence))
end

serialized_outputs = ''.b
if (hash_type & SIGHASH_OUTPUT_MASK) != BTC::SIGHASH_SINGLE && (hash_type & SIGHASH_OUTPUT_MASK) != BTC::SIGHASH_NONE
tx.outputs.each do |txout|
serialized_outputs << txout.data
end
elsif (hash_type & SIGHASH_OUTPUT_MASK) == BTC::SIGHASH_SINGLE && input_index < tx.outputs.size
serialized_outputs = tx.outputs[input_index].data
end
hash_outputs = BTC.sha256(BTC.sha256(serialized_outputs))

hash = ''.b
hash << BTC::WireFormat.encode_int32le(version)
hash << hash_prevouts
hash << hash_sequence
hash << tx.inputs[input_index].outpoint.data
hash << BTC::WireFormat.encode_string(output_script.data)
hash << BTC::WireFormat.encode_int64le(amount)
hash << BTC::WireFormat.encode_uint32le(tx.inputs[input_index].sequence)
hash << hash_outputs
hash << BTC::WireFormat.encode_int32le(tx.lock_time)
hash << BTC::WireFormat.encode_uint32le(hash_type)

BTC.sha256(BTC.sha256(hash))
end
end
end
14 changes: 9 additions & 5 deletions lib/btcruby/transaction_input.rb
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -42,8 +42,8 @@ class TransactionInput
# It is set in `tx.add_input` and reset to nil in `tx.remove_all_inputs`.
# Default is nil.
attr_accessor :transaction
# Optional index within owning transaction.

# Optional index within owning transaction.
# It is set in `tx.add_input` and reset to nil in `tx.remove_all_inputs`.
# Default is nil.
attr_accessor :index
Expand All @@ -55,6 +55,10 @@ class TransactionInput
# Default is transaction_output.value or nil.
attr_accessor :value

# BTC::Script instance that proves ownership of the previous transaction output.
# Contains the signature itself as defined in BIP-141
attr_accessor :witness

# Initializes transaction input with its attributes. Every attribute has a valid default value.
def initialize(data: nil,
stream: nil,
Expand Down Expand Up @@ -200,16 +204,16 @@ def previous_id
def previous_id=(txid)
self.previous_hash = BTC.hash_from_id(txid)
end

def outpoint
Outpoint.new(transaction_hash: previous_hash, index: previous_index)
end

def outpoint=(outpoint)
self.previous_hash = outpoint.transaction_hash
self.previous_index = outpoint.index
end

def final?
self.sequence == MAX_SEQUENCE
end
Expand Down