Class: Bitcoin::Protocol::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/bitcoin/protocol/parser.rb

Overview

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(handler = nil) ⇒ Parser

Returns a new instance of Parser.



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# File 'lib/bitcoin/protocol/parser.rb', line 9

def initialize(handler = nil)
  @h = handler || Handler.new
  @buf = ''
  @stats = { 'total_packets' => 0, 'total_bytes' => 0, 'total_errors' => 0 }
end

Instance Attribute Details

#statsObject (readonly)

Returns the value of attribute stats.



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# File 'lib/bitcoin/protocol/parser.rb', line 7

def stats
  @stats
end

Instance Method Details

#handle_mempool_request(*_) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 122

def handle_mempool_request(*_)
  return unless @version.fields[:version] >= 60_002 # Protocol version >= 60002
  return unless (
    @version.fields[:services] & Bitcoin::Protocol::Version::NODE_NETWORK
  ) == 1 # NODE_NETWORK bit set in Services
  @h.on_mempool if @h.respond_to?(:on_mempool)
end

#handle_notfound_reply(payload) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 130

def handle_notfound_reply(payload)
  return unless @h.respond_to?(:on_notfound)
  _, payload = Protocol.unpack_var_int(payload)
  payload.each_byte.each_slice(36) do |i|
    hash = i[4..-1].reverse.pack('C32')
    case i[0]
    when 1 then @h.on_notfound(:tx, hash)
    when 2 then @h.on_notfound(:block, hash)
    else
      parse_error(:notfound, [i.pack('C*'), hash])
    end
  end
end

#handle_reject(payload) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 151

def handle_reject(payload)
  return unless @h.respond_to?(:on_reject)
  @h.on_reject Bitcoin::Protocol::Reject.parse(payload)
end

#handle_stream_error(type, msg) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 193

def handle_stream_error(type, msg)
  # TODO: replace by writing a real logger/exception handler
  case type
  when :close
    puts "closing packet stream (#{msg})"
  else
    puts [type, msg].inspect
  end
end

#parse(buf) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 156

def parse(buf)
  @buf += buf
  while parse_buffer; end
  @buf
end

#parse_addr(payload) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 84

def parse_addr(payload)
  _, payload = Protocol.unpack_var_int(payload)
  payload.each_byte.each_slice(30) do |i|
    begin
      @h.on_addr(Addr.new(i.pack('C*')))
    rescue StandardError
      parse_error(:addr, i.pack('C*'))
    end
  end
end

#parse_alert(payload) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 108

def parse_alert(payload)
  # nop (https://github.com/lian/bitcoin-ruby/issues/268)
end

#parse_bufferObject



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# File 'lib/bitcoin/protocol/parser.rb', line 162

def parse_buffer
  head_magic = Bitcoin.network[:magic_head]
  head_size  = 24
  return false if @buf.size < head_size

  magic, cmd, length, checksum = @buf.unpack('a4A12Va4')
  payload = @buf[head_size...head_size + length]

  if magic == head_magic

    if Digest::SHA256.digest(Digest::SHA256.digest(payload))[0...4] != checksum
      if (length < 50_000) && (payload.size < length)
        size_info = [payload.size, length].join('/')
        handle_stream_error(:debug, "chunked packet stream (#{size_info})")
      else
        handle_stream_error(:close, 'checksum mismatch')
      end
      return
    end
    @buf = @buf[head_size + length..-1] || ''

    process_pkt(cmd, payload)
  else
    handle_stream_error(:close, 'head_magic not found')
    @buf = ''
  end

  # not empty yet? parse more.
  !@buf[0].nil?
end

#parse_error(*err) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 203

def parse_error(*err)
  @stats['total_errors'] += 1
  return unless @h.respond_to?(:on_error)
  @h.on_error(*err)
end

#parse_getblocks(payload) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 112

def parse_getblocks(payload)
  version, payload = payload.unpack('Va*')
  count, payload = Protocol.unpack_var_int(payload)
  buf, payload = payload.unpack("a#{count * 32}a*")
  hashes = buf.each_byte.each_slice(32).map { |i| i.reverse.pack('C32').hth }
  stop_hash = payload[0..32].reverse_hth
  [version, hashes, stop_hash]
end

#parse_headers(payload) ⇒ Object

rubocop:enable CyclomaticComplexity



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# File 'lib/bitcoin/protocol/parser.rb', line 47

def parse_headers(payload)
  return unless @h.respond_to?(:on_headers)
  buf = StringIO.new(payload)
  count = Protocol.unpack_var_int_from_io(buf)
  headers = Array.new(count) do
    break if buf.eof?
    b = Block.new
    b.parse_data_from_io(buf, true)
    b
  end
  @h.on_headers(headers)
end

#parse_inv(payload, type = :put) ⇒ Object

handles inv/getdata packets



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# File 'lib/bitcoin/protocol/parser.rb', line 61

def parse_inv(payload, type = :put)
  count, payload = Protocol.unpack_var_int(payload)
  payload.each_byte.each_slice(36).with_index do |i, idx|
    hash = i[4..-1].reverse.pack('C32')
    case i[0]
    when 1
      type == :put ? @h.on_inv_transaction(hash) : @h.on_get_transaction(hash)
    when 2
      if type == :put
        if @h.respond_to?(:on_inv_block_v2)
          @h.on_inv_block_v2(hash, idx, count)
        else
          @h.on_inv_block(hash)
        end
      else
        @h.on_get_block(hash)
      end
    else
      parse_error :parse_inv, i.pack('C*')
    end
  end
end

#parse_mrkle_block(payload) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 144

def parse_mrkle_block(payload)
  return unless @h.respond_to?(:on_mrkle_block)
  b = Block.new
  b.parse_data_from_io(payload, :filtered)
  @h.on_mrkle_block(b)
end

#parse_verackObject



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# File 'lib/bitcoin/protocol/parser.rb', line 95

def parse_verack
  if @h.respond_to?(:on_verack)
    @h.on_verack
  else
    @h.respond_to?(:on_handshake_complete) ? @h.on_handshake_complete : nil
  end
end

#parse_version(payload) ⇒ Object



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# File 'lib/bitcoin/protocol/parser.rb', line 103

def parse_version(payload)
  @version = Bitcoin::Protocol::Version.parse(payload)
  @h.on_version(@version)
end

#process_pkt(command, payload) ⇒ Object

rubocop:disable CyclomaticComplexity



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# File 'lib/bitcoin/protocol/parser.rb', line 16

def process_pkt(command, payload)
  @stats['total_packets'] += 1
  @stats['total_bytes'] += payload.bytesize
  @stats[command] ? (@stats[command] += 1) : @stats[command] = 1
  case command
  when 'tx' then @h.on_tx(Tx.new(payload))
  when 'block' then @h.on_block(Block.new(payload))
  when 'headers' then parse_headers(payload)
  when 'inv' then parse_inv(payload, :put)
  when 'getdata' then parse_inv(payload, :get)
  when 'addr' then parse_addr(payload)
  when 'getaddr' then @h.on_getaddr if @h.respond_to?(:on_getaddr)
  when 'verack' then parse_verack
  when 'version' then parse_version(payload)
  when 'alert' then parse_alert(payload)
  when 'ping' then @h.on_ping(payload.unpack('Q')[0])
  when 'pong' then @h.on_pong(payload.unpack('Q')[0])
  when 'getblocks' then @h.on_getblocks(*parse_getblocks(payload)) \
    if @h.respond_to?(:on_getblocks)
  when 'getheaders' then @h.on_getheaders(*parse_getblocks(payload)) \
    if @h.respond_to?(:on_getheaders)
  when 'mempool' then handle_mempool_request(payload)
  when 'notfound' then handle_notfound_reply(payload)
  when 'merkleblock' then parse_mrkle_block(payload)
  when 'reject' then handle_reject(payload)
  else
    parse_error :unknown_packet, [command, payload.hth]
  end
end