text: # mininode.py - Bitcoin P2P network half-a-node
  #
  # Distributed under the MIT/X11 software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  #
  # This python code was modified from ArtForz' public domain  half-a-node, as
  # found in the mini-node branch of http://github.com/jgarzik/pynode.
  #
  # NodeConn: an object which manages p2p connectivity to a bitcoin node
  # NodeConnCB: a base class that describes the interface for receiving
  #             callbacks with network messages from a NodeConn
  # CBlock, CTransaction, CBlockHeader, CTxIn, CTxOut, etc....:
  #     data structures that should map to corresponding structures in
  #     bitcoin/primitives
  # msg_block, msg_tx, msg_headers, etc.:
  #     data structures that represent network messages
  # ser_*, deser_*: functions that handle serialization/deserialization
  
  
  import struct
  import socket
  import asyncore
  import binascii
  import time
  import sys
  import random
  import cStringIO
  import hashlib
  from threading import RLock
  from threading import Thread
  import logging
  import copy
  from pyblake2 import blake2b
  
  from .equihash import (
      gbp_basic,
      gbp_validate,
      hash_nonce,
      zcash_person,
  )
  
  OVERWINTER_PROTO_VERSION = 170005
  BIP0031_VERSION = 60000
  SPROUT_PROTO_VERSION = 170004  # past bip-31 for ping/pong
  SAPLING_PROTO_VERSION = 170006
  MY_SUBVERSION = "/python-mininode-tester:0.0.1/"
  
  
  OVERWINTER_VERSION_GROUP_ID = 0x03C48270
  
  MAX_INV_SZ = 50000
  
  
  COIN = 100000000 # 1 ltz in zatoshis
  
  # Keep our own socket map for asyncore, so that we can track disconnects
  # ourselves (to workaround an issue with closing an asyncore socket when
  # using select)
  mininode_socket_map = dict()
  
  # One lock for synchronizing all data access between the networking thread (see
  # NetworkThread below) and the thread running the test logic.  For simplicity,
  # NodeConn acquires this lock whenever delivering a message to to a NodeConnCB,
  # and whenever adding anything to the send buffer (in send_message()).  This
  # lock should be acquired in the thread running the test logic to synchronize
  # access to any data shared with the NodeConnCB or NodeConn.
  mininode_lock = RLock()
  
  # Serialization/deserialization tools
  def sha256(s):
      return hashlib.new('sha256', s).digest()
  
  
  def hash256(s):
      return sha256(sha256(s))
  
  
  def deser_string(f):
      nit = struct.unpack("<B", f.read(1))[0]
      if nit == 253:
          nit = struct.unpack("<H", f.read(2))[0]
      elif nit == 254:
          nit = struct.unpack("<I", f.read(4))[0]
      elif nit == 255:
          nit = struct.unpack("<Q", f.read(8))[0]
      return f.read(nit)
  
  
  def ser_string(s):
      if len(s) < 253:
          return chr(len(s)) + s
      elif len(s) < 0x10000:
          return chr(253) + struct.pack("<H", len(s)) + s
      elif len(s) < 0x100000000L:
          return chr(254) + struct.pack("<I", len(s)) + s
      return chr(255) + struct.pack("<Q", len(s)) + s
  
  
  def deser_uint256(f):
      r = 0L
      for i in xrange(8):
          t = struct.unpack("<I", f.read(4))[0]
          r += t << (i * 32)
      return r
  
  
  def ser_uint256(u):
      rs = ""
      for i in xrange(8):
          rs += struct.pack("<I", u & 0xFFFFFFFFL)
          u >>= 32
      return rs
  
  
  def uint256_from_str(s):
      r = 0L
      t = struct.unpack("<IIIIIIII", s[:32])
      for i in xrange(8):
          r += t[i] << (i * 32)
      return r
  
  
  def uint256_from_compact(c):
      nbytes = (c >> 24) & 0xFF
      v = (c & 0xFFFFFFL) << (8 * (nbytes - 3))
      return v
  
  
  def deser_vector(f, c):
      nit = struct.unpack("<B", f.read(1))[0]
      if nit == 253:
          nit = struct.unpack("<H", f.read(2))[0]
      elif nit == 254:
          nit = struct.unpack("<I", f.read(4))[0]
      elif nit == 255:
          nit = struct.unpack("<Q", f.read(8))[0]
      r = []
      for i in xrange(nit):
          t = c()
          t.deserialize(f)
          r.append(t)
      return r
  
  
  def ser_vector(l):
      r = ""
      if len(l) < 253:
          r = chr(len(l))
      elif len(l) < 0x10000:
          r = chr(253) + struct.pack("<H", len(l))
      elif len(l) < 0x100000000L:
          r = chr(254) + struct.pack("<I", len(l))
      else:
          r = chr(255) + struct.pack("<Q", len(l))
      for i in l:
          r += i.serialize()
      return r
  
  
  def deser_uint256_vector(f):
      nit = struct.unpack("<B", f.read(1))[0]
      if nit == 253:
          nit = struct.unpack("<H", f.read(2))[0]
      elif nit == 254:
          nit = struct.unpack("<I", f.read(4))[0]
      elif nit == 255:
          nit = struct.unpack("<Q", f.read(8))[0]
      r = []
      for i in xrange(nit):
          t = deser_uint256(f)
          r.append(t)
      return r
  
  
  def ser_uint256_vector(l):
      r = ""
      if len(l) < 253:
          r = chr(len(l))
      elif len(l) < 0x10000:
          r = chr(253) + struct.pack("<H", len(l))
      elif len(l) < 0x100000000L:
          r = chr(254) + struct.pack("<I", len(l))
      else:
          r = chr(255) + struct.pack("<Q", len(l))
      for i in l:
          r += ser_uint256(i)
      return r
  
  
  def deser_string_vector(f):
      nit = struct.unpack("<B", f.read(1))[0]
      if nit == 253:
          nit = struct.unpack("<H", f.read(2))[0]
      elif nit == 254:
          nit = struct.unpack("<I", f.read(4))[0]
      elif nit == 255:
          nit = struct.unpack("<Q", f.read(8))[0]
      r = []
      for i in xrange(nit):
          t = deser_string(f)
          r.append(t)
      return r
  
  
  def ser_string_vector(l):
      r = ""
      if len(l) < 253:
          r = chr(len(l))
      elif len(l) < 0x10000:
          r = chr(253) + struct.pack("<H", len(l))
      elif len(l) < 0x100000000L:
          r = chr(254) + struct.pack("<I", len(l))
      else:
          r = chr(255) + struct.pack("<Q", len(l))
      for sv in l:
          r += ser_string(sv)
      return r
  
  
  def deser_int_vector(f):
      nit = struct.unpack("<B", f.read(1))[0]
      if nit == 253:
          nit = struct.unpack("<H", f.read(2))[0]
      elif nit == 254:
          nit = struct.unpack("<I", f.read(4))[0]
      elif nit == 255:
          nit = struct.unpack("<Q", f.read(8))[0]
      r = []
      for i in xrange(nit):
          t = struct.unpack("<i", f.read(4))[0]
          r.append(t)
      return r
  
  
  def ser_int_vector(l):
      r = ""
      if len(l) < 253:
          r = chr(len(l))
      elif len(l) < 0x10000:
          r = chr(253) + struct.pack("<H", len(l))
      elif len(l) < 0x100000000L:
          r = chr(254) + struct.pack("<I", len(l))
      else:
          r = chr(255) + struct.pack("<Q", len(l))
      for i in l:
          r += struct.pack("<i", i)
      return r
  
  
  def deser_char_vector(f):
      nit = struct.unpack("<B", f.read(1))[0]
      if nit == 253:
          nit = struct.unpack("<H", f.read(2))[0]
      elif nit == 254:
          nit = struct.unpack("<I", f.read(4))[0]
      elif nit == 255:
          nit = struct.unpack("<Q", f.read(8))[0]
      r = []
      for i in xrange(nit):
          t = struct.unpack("<B", f.read(1))[0]
          r.append(t)
      return r
  
  
  def ser_char_vector(l):
      r = ""
      if len(l) < 253:
          r = chr(len(l))
      elif len(l) < 0x10000:
          r = chr(253) + struct.pack("<H", len(l))
      elif len(l) < 0x100000000L:
          r = chr(254) + struct.pack("<I", len(l))
      else:
          r = chr(255) + struct.pack("<Q", len(l))
      for i in l:
          r += chr(i)
      return r
  
  
  # Objects that map to litecoinzd objects, which can be serialized/deserialized
  
  class CAddress(object):
      def __init__(self):
          self.nServices = 1
          self.pchReserved = "\x00" * 10 + "\xff" * 2
          self.ip = "0.0.0.0"
          self.port = 0
  
      def deserialize(self, f):
          self.nServices = struct.unpack("<Q", f.read(8))[0]
          self.pchReserved = f.read(12)
          self.ip = socket.inet_ntoa(f.read(4))
          self.port = struct.unpack(">H", f.read(2))[0]
  
      def serialize(self):
          r = ""
          r += struct.pack("<Q", self.nServices)
          r += self.pchReserved
          r += socket.inet_aton(self.ip)
          r += struct.pack(">H", self.port)
          return r
  
      def __repr__(self):
          return "CAddress(nServices=%i ip=%s port=%i)" % (self.nServices,
                                                           self.ip, self.port)
  
  
  class CInv(object):
      typemap = {
          0: "Error",
          1: "TX",
          2: "Block"}
  
      def __init__(self, t=0, h=0L):
          self.type = t
          self.hash = h
  
      def deserialize(self, f):
          self.type = struct.unpack("<i", f.read(4))[0]
          self.hash = deser_uint256(f)
  
      def serialize(self):
          r = ""
          r += struct.pack("<i", self.type)
          r += ser_uint256(self.hash)
          return r
  
      def __repr__(self):
          return "CInv(type=%s hash=%064x)" \
              % (self.typemap[self.type], self.hash)
  
  
  class CBlockLocator(object):
      def __init__(self):
          self.nVersion = SPROUT_PROTO_VERSION
          self.vHave = []
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          self.vHave = deser_uint256_vector(f)
  
      def serialize(self):
          r = ""
          r += struct.pack("<i", self.nVersion)
          r += ser_uint256_vector(self.vHave)
          return r
  
      def __repr__(self):
          return "CBlockLocator(nVersion=%i vHave=%s)" \
              % (self.nVersion, repr(self.vHave))
  
  
  G1_PREFIX_MASK = 0x02
  G2_PREFIX_MASK = 0x0a
  
  class ZCProof(object):
      def __init__(self):
          self.g_A = None
          self.g_A_prime = None
          self.g_B = None
          self.g_B_prime = None
          self.g_C = None
          self.g_C_prime = None
          self.g_K = None
          self.g_H = None
  
      def deserialize(self, f):
          def deser_g1(self, f):
              leadingByte = struct.unpack("<B", f.read(1))[0]
              return {
                  'y_lsb': leadingByte & 1,
                  'x': f.read(32),
              }
          def deser_g2(self, f):
              leadingByte = struct.unpack("<B", f.read(1))[0]
              return {
                  'y_gt': leadingByte & 1,
                  'x': f.read(64),
              }
          self.g_A = deser_g1(f)
          self.g_A_prime = deser_g1(f)
          self.g_B = deser_g2(f)
          self.g_B_prime = deser_g1(f)
          self.g_C = deser_g1(f)
          self.g_C_prime = deser_g1(f)
          self.g_K = deser_g1(f)
          self.g_H = deser_g1(f)
  
      def serialize(self):
          def ser_g1(self, p):
              return chr(G1_PREFIX_MASK | p['y_lsb']) + p['x']
          def ser_g2(self, p):
              return chr(G2_PREFIX_MASK | p['y_gt']) + p['x']
          r = ""
          r += ser_g1(self.g_A)
          r += ser_g1(self.g_A_prime)
          r += ser_g2(self.g_B)
          r += ser_g1(self.g_B_prime)
          r += ser_g1(self.g_C)
          r += ser_g1(self.g_C_prime)
          r += ser_g1(self.g_K)
          r += ser_g1(self.g_H)
          return r
  
      def __repr__(self):
          return "ZCProof(g_A=%s g_A_prime=%s g_B=%s g_B_prime=%s g_C=%s g_C_prime=%s g_K=%s g_H=%s)" \
              % (repr(self.g_A), repr(self.g_A_prime),
                 repr(self.g_B), repr(self.g_B_prime),
                 repr(self.g_C), repr(self.g_C_prime),
                 repr(self.g_K), repr(self.g_H))
  
  
  ZC_NUM_JS_INPUTS = 2
  ZC_NUM_JS_OUTPUTS = 2
  
  ZC_NOTEPLAINTEXT_LEADING = 1
  ZC_V_SIZE = 8
  ZC_RHO_SIZE = 32
  ZC_R_SIZE = 32
  ZC_MEMO_SIZE = 512
  
  ZC_NOTEPLAINTEXT_SIZE = (
    ZC_NOTEPLAINTEXT_LEADING +
    ZC_V_SIZE +
    ZC_RHO_SIZE +
    ZC_R_SIZE +
    ZC_MEMO_SIZE
  )
  
  NOTEENCRYPTION_AUTH_BYTES = 16
  
  ZC_NOTECIPHERTEXT_SIZE = (
    ZC_NOTEPLAINTEXT_SIZE +
    NOTEENCRYPTION_AUTH_BYTES
  )
  
  class JSDescription(object):
      def __init__(self):
          self.vpub_old = 0
          self.vpub_new = 0
          self.anchor = 0
          self.nullifiers = [0] * ZC_NUM_JS_INPUTS
          self.commitments = [0] * ZC_NUM_JS_OUTPUTS
          self.onetimePubKey = 0
          self.randomSeed = 0
          self.macs = [0] * ZC_NUM_JS_INPUTS
          self.proof = None
          self.ciphertexts = [None] * ZC_NUM_JS_OUTPUTS
  
      def deserialize(self, f):
          self.vpub_old = struct.unpack("<q", f.read(8))[0]
          self.vpub_new = struct.unpack("<q", f.read(8))[0]
          self.anchor = deser_uint256(f)
  
          self.nullifiers = []
          for i in range(ZC_NUM_JS_INPUTS):
              self.nullifiers.append(deser_uint256(f))
  
          self.commitments = []
          for i in range(ZC_NUM_JS_OUTPUTS):
              self.commitments.append(deser_uint256(f))
  
          self.onetimePubKey = deser_uint256(f)
          self.randomSeed = deser_uint256(f)
  
          self.macs = []
          for i in range(ZC_NUM_JS_INPUTS):
              self.macs.append(deser_uint256(f))
  
          self.proof = ZCProof()
          self.proof.deserialize(f)
  
          self.ciphertexts = []
          for i in range(ZC_NUM_JS_OUTPUTS):
              self.ciphertexts.append(f.read(ZC_NOTECIPHERTEXT_SIZE))
  
      def serialize(self):
          r = ""
          r += struct.pack("<q", self.vpub_old)
          r += struct.pack("<q", self.vpub_new)
          r += ser_uint256(self.anchor)
          for i in range(ZC_NUM_JS_INPUTS):
              r += ser_uint256(self.nullifiers[i])
          for i in range(ZC_NUM_JS_OUTPUTS):
              r += ser_uint256(self.commitments[i])
          r += ser_uint256(self.onetimePubKey)
          r += ser_uint256(self.randomSeed)
          for i in range(ZC_NUM_JS_INPUTS):
              r += ser_uint256(self.macs[i])
          r += self.proof.serialize()
          for i in range(ZC_NUM_JS_OUTPUTS):
              r += ser_uint256(self.ciphertexts[i])
          return r
  
      def __repr__(self):
          return "JSDescription(vpub_old=%i.%08i vpub_new=%i.%08i anchor=%064x onetimePubKey=%064x randomSeed=%064x proof=%s)" \
              % (self.vpub_old, self.vpub_new, self.anchor,
                 self.onetimePubKey, self.randomSeed, repr(self.proof))
  
  
  class COutPoint(object):
      def __init__(self, hash=0, n=0):
          self.hash = hash
          self.n = n
  
      def deserialize(self, f):
          self.hash = deser_uint256(f)
          self.n = struct.unpack("<I", f.read(4))[0]
  
      def serialize(self):
          r = ""
          r += ser_uint256(self.hash)
          r += struct.pack("<I", self.n)
          return r
  
      def __repr__(self):
          return "COutPoint(hash=%064x n=%i)" % (self.hash, self.n)
  
  
  class CTxIn(object):
      def __init__(self, outpoint=None, scriptSig="", nSequence=0):
          if outpoint is None:
              self.prevout = COutPoint()
          else:
              self.prevout = outpoint
          self.scriptSig = scriptSig
          self.nSequence = nSequence
  
      def deserialize(self, f):
          self.prevout = COutPoint()
          self.prevout.deserialize(f)
          self.scriptSig = deser_string(f)
          self.nSequence = struct.unpack("<I", f.read(4))[0]
  
      def serialize(self):
          r = ""
          r += self.prevout.serialize()
          r += ser_string(self.scriptSig)
          r += struct.pack("<I", self.nSequence)
          return r
  
      def __repr__(self):
          return "CTxIn(prevout=%s scriptSig=%s nSequence=%i)" \
              % (repr(self.prevout), binascii.hexlify(self.scriptSig),
                 self.nSequence)
  
  
  class CTxOut(object):
      def __init__(self, nValue=0, scriptPubKey=""):
          self.nValue = nValue
          self.scriptPubKey = scriptPubKey
  
      def deserialize(self, f):
          self.nValue = struct.unpack("<q", f.read(8))[0]
          self.scriptPubKey = deser_string(f)
  
      def serialize(self):
          r = ""
          r += struct.pack("<q", self.nValue)
          r += ser_string(self.scriptPubKey)
          return r
  
      def __repr__(self):
          return "CTxOut(nValue=%i.%08i scriptPubKey=%s)" \
              % (self.nValue // 100000000, self.nValue % 100000000,
                 binascii.hexlify(self.scriptPubKey))
  
  
  class CTransaction(object):
      def __init__(self, tx=None):
          if tx is None:
              self.fOverwintered = False
              self.nVersion = 1
              self.nVersionGroupId = 0
              self.vin = []
              self.vout = []
              self.nLockTime = 0
              self.nExpiryHeight = 0
              self.vjoinsplit = []
              self.joinSplitPubKey = None
              self.joinSplitSig = None
              self.sha256 = None
              self.hash = None
          else:
              self.fOverwintered = tx.fOverwintered
              self.nVersion = tx.nVersion
              self.nVersionGroupId = tx.nVersionGroupId
              self.vin = copy.deepcopy(tx.vin)
              self.vout = copy.deepcopy(tx.vout)
              self.nLockTime = tx.nLockTime
              self.nExpiryHeight = tx.nExpiryHeight
              self.vjoinsplit = copy.deepcopy(tx.vjoinsplit)
              self.joinSplitPubKey = tx.joinSplitPubKey
              self.joinSplitSig = tx.joinSplitSig
              self.sha256 = None
              self.hash = None
  
      def deserialize(self, f):
          header = struct.unpack("<I", f.read(4))[0]
          self.fOverwintered = bool(header >> 31)
          self.nVersion = header & 0x7FFFFFFF
          self.nVersionGroupId = (struct.unpack("<I", f.read(4))[0]
                                  if self.fOverwintered else 0)
  
          isOverwinterV3 = (self.fOverwintered and
                            self.nVersionGroupId == OVERWINTER_VERSION_GROUP_ID and
                            self.nVersion == 3)
  
          self.vin = deser_vector(f, CTxIn)
          self.vout = deser_vector(f, CTxOut)
          self.nLockTime = struct.unpack("<I", f.read(4))[0]
          if isOverwinterV3:
              self.nExpiryHeight = struct.unpack("<I", f.read(4))[0]
  
          if self.nVersion >= 2:
              self.vjoinsplit = deser_vector(f, JSDescription)
              if len(self.vjoinsplit) > 0:
                  self.joinSplitPubKey = deser_uint256(f)
                  self.joinSplitSig = f.read(64)
  
          self.sha256 = None
          self.hash = None
  
      def serialize(self):
          header = (int(self.fOverwintered)<<31) | self.nVersion
          isOverwinterV3 = (self.fOverwintered and
                            self.nVersionGroupId == OVERWINTER_VERSION_GROUP_ID and
                            self.nVersion == 3)
  
          r = ""
          r += struct.pack("<I", header)
          if self.fOverwintered:
              r += struct.pack("<I", self.nVersionGroupId)
          r += ser_vector(self.vin)
          r += ser_vector(self.vout)
          r += struct.pack("<I", self.nLockTime)
          if isOverwinterV3:
              r += struct.pack("<I", self.nExpiryHeight)
          if self.nVersion >= 2:
              r += ser_vector(self.vjoinsplit)
              if len(self.vjoinsplit) > 0:
                  r += ser_uint256(self.joinSplitPubKey)
                  r += self.joinSplitSig
          return r
  
      def rehash(self):
          self.sha256 = None
          self.calc_sha256()
  
      def calc_sha256(self):
          if self.sha256 is None:
              self.sha256 = uint256_from_str(hash256(self.serialize()))
          self.hash = hash256(self.serialize())[::-1].encode('hex_codec')
  
      def is_valid(self):
          self.calc_sha256()
          for tout in self.vout:
              if tout.nValue < 0 or tout.nValue > 21000000L * 100000000L:
                  return False
          return True
  
      def __repr__(self):
          r = ("CTransaction(fOverwintered=%r nVersion=%i nVersionGroupId=0x%08x "
               "vin=%s vout=%s nLockTime=%i nExpiryHeight=%i"
               % (self.fOverwintered, self.nVersion, self.nVersionGroupId,
                  repr(self.vin), repr(self.vout), self.nLockTime, self.nExpiryHeight))
          if self.nVersion >= 2:
              r += " vjoinsplit=%s" % repr(self.vjoinsplit)
              if len(self.vjoinsplit) > 0:
                  r += " joinSplitPubKey=%064x joinSplitSig=%064x" \
                      (self.joinSplitPubKey, self.joinSplitSig)
          r += ")"
          return r
  
  
  class CBlockHeader(object):
      def __init__(self, header=None):
          if header is None:
              self.set_null()
          else:
              self.nVersion = header.nVersion
              self.hashPrevBlock = header.hashPrevBlock
              self.hashMerkleRoot = header.hashMerkleRoot
              self.hashReserved = header.hashReserved
              self.nTime = header.nTime
              self.nBits = header.nBits
              self.nNonce = header.nNonce
              self.nSolution = header.nSolution
              self.sha256 = header.sha256
              self.hash = header.hash
              self.calc_sha256()
  
      def set_null(self):
          self.nVersion = 4
          self.hashPrevBlock = 0
          self.hashMerkleRoot = 0
          self.hashReserved = 0
          self.nTime = 0
          self.nBits = 0
          self.nNonce = 0
          self.nSolution = []
          self.sha256 = None
          self.hash = None
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          self.hashPrevBlock = deser_uint256(f)
          self.hashMerkleRoot = deser_uint256(f)
          self.hashReserved = deser_uint256(f)
          self.nTime = struct.unpack("<I", f.read(4))[0]
          self.nBits = struct.unpack("<I", f.read(4))[0]
          self.nNonce = deser_uint256(f)
          self.nSolution = deser_char_vector(f)
          self.sha256 = None
          self.hash = None
  
      def serialize(self):
          r = ""
          r += struct.pack("<i", self.nVersion)
          r += ser_uint256(self.hashPrevBlock)
          r += ser_uint256(self.hashMerkleRoot)
          r += ser_uint256(self.hashReserved)
          r += struct.pack("<I", self.nTime)
          r += struct.pack("<I", self.nBits)
          r += ser_uint256(self.nNonce)
          r += ser_char_vector(self.nSolution)
          return r
  
      def calc_sha256(self):
          if self.sha256 is None:
              r = ""
              r += struct.pack("<i", self.nVersion)
              r += ser_uint256(self.hashPrevBlock)
              r += ser_uint256(self.hashMerkleRoot)
              r += ser_uint256(self.hashReserved)
              r += struct.pack("<I", self.nTime)
              r += struct.pack("<I", self.nBits)
              r += ser_uint256(self.nNonce)
              r += ser_char_vector(self.nSolution)
              self.sha256 = uint256_from_str(hash256(r))
              self.hash = hash256(r)[::-1].encode('hex_codec')
  
      def rehash(self):
          self.sha256 = None
          self.calc_sha256()
          return self.sha256
  
      def __repr__(self):
          return "CBlockHeader(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x hashReserved=%064x nTime=%s nBits=%08x nNonce=%064x nSolution=%s)" \
              % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot, self.hashReserved,
                 time.ctime(self.nTime), self.nBits, self.nNonce, repr(self.nSolution))
  
  
  class CBlock(CBlockHeader):
      def __init__(self, header=None):
          super(CBlock, self).__init__(header)
          self.vtx = []
  
      def deserialize(self, f):
          super(CBlock, self).deserialize(f)
          self.vtx = deser_vector(f, CTransaction)
  
      def serialize(self):
          r = ""
          r += super(CBlock, self).serialize()
          r += ser_vector(self.vtx)
          return r
  
      def calc_merkle_root(self):
          hashes = []
          for tx in self.vtx:
              tx.calc_sha256()
              hashes.append(ser_uint256(tx.sha256))
          while len(hashes) > 1:
              newhashes = []
              for i in xrange(0, len(hashes), 2):
                  i2 = min(i+1, len(hashes)-1)
                  newhashes.append(hash256(hashes[i] + hashes[i2]))
              hashes = newhashes
          return uint256_from_str(hashes[0])
  
      def is_valid(self, n=48, k=5):
          # H(I||...
          digest = blake2b(digest_size=(512/n)*n/8, person=zcash_person(n, k))
          digest.update(super(CBlock, self).serialize()[:108])
          hash_nonce(digest, self.nNonce)
          if not gbp_validate(self.nSolution, digest, n, k):
              return False
          self.calc_sha256()
          target = uint256_from_compact(self.nBits)
          if self.sha256 > target:
              return False
          for tx in self.vtx:
              if not tx.is_valid():
                  return False
          if self.calc_merkle_root() != self.hashMerkleRoot:
              return False
          return True
  
      def solve(self, n=48, k=5):
          target = uint256_from_compact(self.nBits)
          # H(I||...
          digest = blake2b(digest_size=(512/n)*n/8, person=zcash_person(n, k))
          digest.update(super(CBlock, self).serialize()[:108])
          self.nNonce = 0
          while True:
              # H(I||V||...
              curr_digest = digest.copy()
              hash_nonce(curr_digest, self.nNonce)
              # (x_1, x_2, ...) = A(I, V, n, k)
              solns = gbp_basic(curr_digest, n, k)
              for soln in solns:
                  assert(gbp_validate(curr_digest, soln, n, k))
                  self.nSolution = soln
                  self.rehash()
                  if self.sha256 <= target:
                      return
              self.nNonce += 1
  
      def __repr__(self):
          return "CBlock(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x hashReserved=%064x nTime=%s nBits=%08x nNonce=%064x nSolution=%s vtx=%s)" \
              % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
                 self.hashReserved, time.ctime(self.nTime), self.nBits,
                 self.nNonce, repr(self.nSolution), repr(self.vtx))
  
  
  class CUnsignedAlert(object):
      def __init__(self):
          self.nVersion = 1
          self.nRelayUntil = 0
          self.nExpiration = 0
          self.nID = 0
          self.nCancel = 0
          self.setCancel = []
          self.nMinVer = 0
          self.nMaxVer = 0
          self.setSubVer = []
          self.nPriority = 0
          self.strComment = ""
          self.strStatusBar = ""
          self.strReserved = ""
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          self.nRelayUntil = struct.unpack("<q", f.read(8))[0]
          self.nExpiration = struct.unpack("<q", f.read(8))[0]
          self.nID = struct.unpack("<i", f.read(4))[0]
          self.nCancel = struct.unpack("<i", f.read(4))[0]
          self.setCancel = deser_int_vector(f)
          self.nMinVer = struct.unpack("<i", f.read(4))[0]
          self.nMaxVer = struct.unpack("<i", f.read(4))[0]
          self.setSubVer = deser_string_vector(f)
          self.nPriority = struct.unpack("<i", f.read(4))[0]
          self.strComment = deser_string(f)
          self.strStatusBar = deser_string(f)
          self.strReserved = deser_string(f)
  
      def serialize(self):
          r = ""
          r += struct.pack("<i", self.nVersion)
          r += struct.pack("<q", self.nRelayUntil)
          r += struct.pack("<q", self.nExpiration)
          r += struct.pack("<i", self.nID)
          r += struct.pack("<i", self.nCancel)
          r += ser_int_vector(self.setCancel)
          r += struct.pack("<i", self.nMinVer)
          r += struct.pack("<i", self.nMaxVer)
          r += ser_string_vector(self.setSubVer)
          r += struct.pack("<i", self.nPriority)
          r += ser_string(self.strComment)
          r += ser_string(self.strStatusBar)
          r += ser_string(self.strReserved)
          return r
  
      def __repr__(self):
          return "CUnsignedAlert(nVersion %d, nRelayUntil %d, nExpiration %d, nID %d, nCancel %d, nMinVer %d, nMaxVer %d, nPriority %d, strComment %s, strStatusBar %s, strReserved %s)" \
              % (self.nVersion, self.nRelayUntil, self.nExpiration, self.nID,
                 self.nCancel, self.nMinVer, self.nMaxVer, self.nPriority,
                 self.strComment, self.strStatusBar, self.strReserved)
  
  
  class CAlert(object):
      def __init__(self):
          self.vchMsg = ""
          self.vchSig = ""
  
      def deserialize(self, f):
          self.vchMsg = deser_string(f)
          self.vchSig = deser_string(f)
  
      def serialize(self):
          r = ""
          r += ser_string(self.vchMsg)
          r += ser_string(self.vchSig)
          return r
  
      def __repr__(self):
          return "CAlert(vchMsg.sz %d, vchSig.sz %d)" \
              % (len(self.vchMsg), len(self.vchSig))
  
  
  # Objects that correspond to messages on the wire
  class msg_version(object):
      command = "version"
  
      def __init__(self, protocol_version=SPROUT_PROTO_VERSION):
          self.nVersion = protocol_version
          self.nServices = 1
          self.nTime = time.time()
          self.addrTo = CAddress()
          self.addrFrom = CAddress()
          self.nNonce = random.getrandbits(64)
          self.strSubVer = MY_SUBVERSION
          self.nStartingHeight = -1
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          if self.nVersion == 10300:
              self.nVersion = 300
          self.nServices = struct.unpack("<Q", f.read(8))[0]
          self.nTime = struct.unpack("<q", f.read(8))[0]
          self.addrTo = CAddress()
          self.addrTo.deserialize(f)
          if self.nVersion >= 106:
              self.addrFrom = CAddress()
              self.addrFrom.deserialize(f)
              self.nNonce = struct.unpack("<Q", f.read(8))[0]
              self.strSubVer = deser_string(f)
              if self.nVersion >= 209:
                  self.nStartingHeight = struct.unpack("<i", f.read(4))[0]
              else:
                  self.nStartingHeight = None
          else:
              self.addrFrom = None
              self.nNonce = None
              self.strSubVer = None
              self.nStartingHeight = None
  
      def serialize(self):
          r = ""
          r += struct.pack("<i", self.nVersion)
          r += struct.pack("<Q", self.nServices)
          r += struct.pack("<q", self.nTime)
          r += self.addrTo.serialize()
          r += self.addrFrom.serialize()
          r += struct.pack("<Q", self.nNonce)
          r += ser_string(self.strSubVer)
          r += struct.pack("<i", self.nStartingHeight)
          return r
  
      def __repr__(self):
          return 'msg_version(nVersion=%i nServices=%i nTime=%s addrTo=%s addrFrom=%s nNonce=0x%016X strSubVer=%s nStartingHeight=%i)' \
              % (self.nVersion, self.nServices, time.ctime(self.nTime),
                 repr(self.addrTo), repr(self.addrFrom), self.nNonce,
                 self.strSubVer, self.nStartingHeight)
  
  
  class msg_verack(object):
      command = "verack"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return ""
  
      def __repr__(self):
          return "msg_verack()"
  
  
  class msg_addr(object):
      command = "addr"
  
      def __init__(self):
          self.addrs = []
  
      def deserialize(self, f):
          self.addrs = deser_vector(f, CAddress)
  
      def serialize(self):
          return ser_vector(self.addrs)
  
      def __repr__(self):
          return "msg_addr(addrs=%s)" % (repr(self.addrs))
  
  
  class msg_alert(object):
      command = "alert"
  
      def __init__(self):
          self.alert = CAlert()
  
      def deserialize(self, f):
          self.alert = CAlert()
          self.alert.deserialize(f)
  
      def serialize(self):
          r = ""
          r += self.alert.serialize()
          return r
  
      def __repr__(self):
          return "msg_alert(alert=%s)" % (repr(self.alert), )
  
  
  class msg_inv(object):
      command = "inv"
  
      def __init__(self, inv=None):
          if inv is None:
              self.inv = []
          else:
              self.inv = inv
  
      def deserialize(self, f):
          self.inv = deser_vector(f, CInv)
  
      def serialize(self):
          return ser_vector(self.inv)
  
      def __repr__(self):
          return "msg_inv(inv=%s)" % (repr(self.inv))
  
  
  class msg_getdata(object):
      command = "getdata"
  
      def __init__(self):
          self.inv = []
  
      def deserialize(self, f):
          self.inv = deser_vector(f, CInv)
  
      def serialize(self):
          return ser_vector(self.inv)
  
      def __repr__(self):
          return "msg_getdata(inv=%s)" % (repr(self.inv))
  
  
  class msg_notfound(object):
      command = "notfound"
  
      def __init__(self):
          self.inv = []
  
      def deserialize(self, f):
          self.inv = deser_vector(f, CInv)
  
      def serialize(self):
          return ser_vector(self.inv)
  
      def __repr__(self):
          return "msg_notfound(inv=%s)" % (repr(self.inv))
  
  
  class msg_getblocks(object):
      command = "getblocks"
  
      def __init__(self):
          self.locator = CBlockLocator()
          self.hashstop = 0L
  
      def deserialize(self, f):
          self.locator = CBlockLocator()
          self.locator.deserialize(f)
          self.hashstop = deser_uint256(f)
  
      def serialize(self):
          r = ""
          r += self.locator.serialize()
          r += ser_uint256(self.hashstop)
          return r
  
      def __repr__(self):
          return "msg_getblocks(locator=%s hashstop=%064x)" \
              % (repr(self.locator), self.hashstop)
  
  
  class msg_tx(object):
      command = "tx"
  
      def __init__(self, tx=CTransaction()):
          self.tx = tx
  
      def deserialize(self, f):
          self.tx.deserialize(f)
  
      def serialize(self):
          return self.tx.serialize()
  
      def __repr__(self):
          return "msg_tx(tx=%s)" % (repr(self.tx))
  
  
  class msg_block(object):
      command = "block"
  
      def __init__(self, block=None):
          if block is None:
              self.block = CBlock()
          else:
              self.block = block
  
      def deserialize(self, f):
          self.block.deserialize(f)
  
      def serialize(self):
          return self.block.serialize()
  
      def __repr__(self):
          return "msg_block(block=%s)" % (repr(self.block))
  
  
  class msg_getaddr(object):
      command = "getaddr"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return ""
  
      def __repr__(self):
          return "msg_getaddr()"
  
  
  class msg_ping_prebip31(object):
      command = "ping"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return ""
  
      def __repr__(self):
          return "msg_ping() (pre-bip31)"
  
  
  class msg_ping(object):
      command = "ping"
  
      def __init__(self, nonce=0L):
          self.nonce = nonce
  
      def deserialize(self, f):
          self.nonce = struct.unpack("<Q", f.read(8))[0]
  
      def serialize(self):
          r = ""
          r += struct.pack("<Q", self.nonce)
          return r
  
      def __repr__(self):
          return "msg_ping(nonce=%08x)" % self.nonce
  
  
  class msg_pong(object):
      command = "pong"
  
      def __init__(self, nonce=0L):
          self.nonce = nonce
  
      def deserialize(self, f):
          self.nonce = struct.unpack("<Q", f.read(8))[0]
  
      def serialize(self):
          r = ""
          r += struct.pack("<Q", self.nonce)
          return r
  
      def __repr__(self):
          return "msg_pong(nonce=%08x)" % self.nonce
  
  
  class msg_mempool(object):
      command = "mempool"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return ""
  
      def __repr__(self):
          return "msg_mempool()"
  
  
  # getheaders message has
  # number of entries
  # vector of hashes
  # hash_stop (hash of last desired block header, 0 to get as many as possible)
  class msg_getheaders(object):
      command = "getheaders"
  
      def __init__(self):
          self.locator = CBlockLocator()
          self.hashstop = 0L
  
      def deserialize(self, f):
          self.locator = CBlockLocator()
          self.locator.deserialize(f)
          self.hashstop = deser_uint256(f)
  
      def serialize(self):
          r = ""
          r += self.locator.serialize()
          r += ser_uint256(self.hashstop)
          return r
  
      def __repr__(self):
          return "msg_getheaders(locator=%s, stop=%064x)" \
              % (repr(self.locator), self.hashstop)
  
  
  # headers message has
  # <count> <vector of block headers>
  class msg_headers(object):
      command = "headers"
  
      def __init__(self):
          self.headers = []
  
      def deserialize(self, f):
          # comment in litecoinzd indicates these should be deserialized as blocks
          blocks = deser_vector(f, CBlock)
          for x in blocks:
              self.headers.append(CBlockHeader(x))
  
      def serialize(self):
          blocks = [CBlock(x) for x in self.headers]
          return ser_vector(blocks)
  
      def __repr__(self):
          return "msg_headers(headers=%s)" % repr(self.headers)
  
  
  class msg_reject(object):
      command = "reject"
  
      def __init__(self):
          self.message = ""
          self.code = ""
          self.reason = ""
          self.data = 0L
  
      def deserialize(self, f):
          self.message = deser_string(f)
          self.code = struct.unpack("<B", f.read(1))[0]
          self.reason = deser_string(f)
          if (self.message == "block" or self.message == "tx"):
              self.data = deser_uint256(f)
  
      def serialize(self):
          r = ser_string(self.message)
          r += struct.pack("<B", self.code)
          r += ser_string(self.reason)
          if (self.message == "block" or self.message == "tx"):
              r += ser_uint256(self.data)
          return r
  
      def __repr__(self):
          return "msg_reject: %s %d %s [%064x]" \
              % (self.message, self.code, self.reason, self.data)
  
  class msg_filteradd(object):
      command = "filteradd"
  
      def __init__(self):
          self.data = ""
  
      def deserialize(self, f):
          self.data = deser_string(f)
  
      def serialize(self):
          return ser_string(self.data)
  
  
      def __repr__(self):
          return "msg_filteradd(data=%s)" % (repr(self.data))
  
  
  class msg_filterclear(object):
      command = "filterclear"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return ""
  
      def __repr__(self):
          return "msg_filterclear()"
  
  
  # This is what a callback should look like for NodeConn
  # Reimplement the on_* functions to provide handling for events
  class NodeConnCB(object):
      def __init__(self):
          self.verack_received = False
  
      # Derived classes should call this function once to set the message map
      # which associates the derived classes' functions to incoming messages
      def create_callback_map(self):
          self.cbmap = {
              "version": self.on_version,
              "verack": self.on_verack,
              "addr": self.on_addr,
              "alert": self.on_alert,
              "inv": self.on_inv,
              "getdata": self.on_getdata,
              "notfound": self.on_notfound,
              "getblocks": self.on_getblocks,
              "tx": self.on_tx,
              "block": self.on_block,
              "getaddr": self.on_getaddr,
              "ping": self.on_ping,
              "pong": self.on_pong,
              "headers": self.on_headers,
              "getheaders": self.on_getheaders,
              "reject": self.on_reject,
              "mempool": self.on_mempool
          }
  
      def deliver(self, conn, message):
          with mininode_lock:
              try:
                  self.cbmap[message.command](conn, message)
              except:
                  print "ERROR delivering %s (%s)" % (repr(message),
                                                      sys.exc_info()[0])
  
      def on_version(self, conn, message):
          if message.nVersion >= 209:
              conn.send_message(msg_verack())
          conn.ver_send = min(SPROUT_PROTO_VERSION, message.nVersion)
          if message.nVersion < 209:
              conn.ver_recv = conn.ver_send
  
      def on_verack(self, conn, message):
          conn.ver_recv = conn.ver_send
          self.verack_received = True
  
      def on_inv(self, conn, message):
          want = msg_getdata()
          for i in message.inv:
              if i.type != 0:
                  want.inv.append(i)
          if len(want.inv):
              conn.send_message(want)
  
      def on_addr(self, conn, message): pass
      def on_alert(self, conn, message): pass
      def on_getdata(self, conn, message): pass
      def on_notfound(self, conn, message): pass
      def on_getblocks(self, conn, message): pass
      def on_tx(self, conn, message): pass
      def on_block(self, conn, message): pass
      def on_getaddr(self, conn, message): pass
      def on_headers(self, conn, message): pass
      def on_getheaders(self, conn, message): pass
      def on_ping(self, conn, message):
          if conn.ver_send > BIP0031_VERSION:
              conn.send_message(msg_pong(message.nonce))
      def on_reject(self, conn, message): pass
      def on_close(self, conn): pass
      def on_mempool(self, conn): pass
      def on_pong(self, conn, message): pass
  
  
  # The actual NodeConn class
  # This class provides an interface for a p2p connection to a specified node
  class NodeConn(asyncore.dispatcher):
      messagemap = {
          "version": msg_version,
          "verack": msg_verack,
          "addr": msg_addr,
          "alert": msg_alert,
          "inv": msg_inv,
          "getdata": msg_getdata,
          "notfound": msg_notfound,
          "getblocks": msg_getblocks,
          "tx": msg_tx,
          "block": msg_block,
          "getaddr": msg_getaddr,
          "ping": msg_ping,
          "pong": msg_pong,
          "headers": msg_headers,
          "getheaders": msg_getheaders,
          "reject": msg_reject,
          "mempool": msg_mempool
      }
      MAGIC_BYTES = {
          "mainnet": "\x24\xe9\x27\x64",   # mainnet
          "testnet3": "\xfa\x1a\xf9\xbf",  # testnet3
          "regtest": "\xaa\xe8\x3f\x5f"    # regtest
      }
  
      def __init__(self, dstaddr, dstport, rpc, callback, net="regtest", protocol_version=SPROUT_PROTO_VERSION):
          asyncore.dispatcher.__init__(self, map=mininode_socket_map)
          self.log = logging.getLogger("NodeConn(%s:%d)" % (dstaddr, dstport))
          self.dstaddr = dstaddr
          self.dstport = dstport
          self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
          self.sendbuf = ""
          self.recvbuf = ""
          self.ver_send = 209
          self.ver_recv = 209
          self.last_sent = 0
          self.state = "connecting"
          self.network = net
          self.cb = callback
          self.disconnect = False
  
          # stuff version msg into sendbuf
          vt = msg_version(protocol_version)
          vt.addrTo.ip = self.dstaddr
          vt.addrTo.port = self.dstport
          vt.addrFrom.ip = "0.0.0.0"
          vt.addrFrom.port = 0
          self.send_message(vt, True)
          print 'MiniNode: Connecting to Bitcoin Node IP # ' + dstaddr + ':' \
              + str(dstport) + ' using version ' + str(protocol_version)
  
          try:
              self.connect((dstaddr, dstport))
          except:
              self.handle_close()
          self.rpc = rpc
  
      def show_debug_msg(self, msg):
          self.log.debug(msg)
  
      def handle_connect(self):
          self.show_debug_msg("MiniNode: Connected & Listening: \n")
          self.state = "connected"
  
      def handle_close(self):
          self.show_debug_msg("MiniNode: Closing Connection to %s:%d... "
                              % (self.dstaddr, self.dstport))
          self.state = "closed"
          self.recvbuf = ""
          self.sendbuf = ""
          try:
              self.close()
          except:
              pass
          self.cb.on_close(self)
  
      def handle_read(self):
          try:
              t = self.recv(8192)
              if len(t) > 0:
                  self.recvbuf += t
                  self.got_data()
          except:
              pass
  
      def readable(self):
          return True
  
      def writable(self):
          with mininode_lock:
              length = len(self.sendbuf)
          return (length > 0)
  
      def handle_write(self):
          with mininode_lock:
              try:
                  sent = self.send(self.sendbuf)
              except:
                  self.handle_close()
                  return
              self.sendbuf = self.sendbuf[sent:]
  
      def got_data(self):
          while True:
              if len(self.recvbuf) < 4:
                  return
              if self.recvbuf[:4] != self.MAGIC_BYTES[self.network]:
                  raise ValueError("got garbage %s" % repr(self.recvbuf))
              if self.ver_recv < 209:
                  if len(self.recvbuf) < 4 + 12 + 4:
                      return
                  command = self.recvbuf[4:4+12].split("\x00", 1)[0]
                  msglen = struct.unpack("<i", self.recvbuf[4+12:4+12+4])[0]
                  checksum = None
                  if len(self.recvbuf) < 4 + 12 + 4 + msglen:
                      return
                  msg = self.recvbuf[4+12+4:4+12+4+msglen]
                  self.recvbuf = self.recvbuf[4+12+4+msglen:]
              else:
                  if len(self.recvbuf) < 4 + 12 + 4 + 4:
                      return
                  command = self.recvbuf[4:4+12].split("\x00", 1)[0]
                  msglen = struct.unpack("<i", self.recvbuf[4+12:4+12+4])[0]
                  checksum = self.recvbuf[4+12+4:4+12+4+4]
                  if len(self.recvbuf) < 4 + 12 + 4 + 4 + msglen:
                      return
                  msg = self.recvbuf[4+12+4+4:4+12+4+4+msglen]
                  th = sha256(msg)
                  h = sha256(th)
                  if checksum != h[:4]:
                      raise ValueError("got bad checksum " + repr(self.recvbuf))
                  self.recvbuf = self.recvbuf[4+12+4+4+msglen:]
              if command in self.messagemap:
                  f = cStringIO.StringIO(msg)
                  t = self.messagemap[command]()
                  t.deserialize(f)
                  self.got_message(t)
              else:
                  self.show_debug_msg("Unknown command: '" + command + "' " +
                                      repr(msg))
  
      def send_message(self, message, pushbuf=False):
          if self.state != "connected" and not pushbuf:
              return
          self.show_debug_msg("Send %s" % repr(message))
          command = message.command
          data = message.serialize()
          tmsg = self.MAGIC_BYTES[self.network]
          tmsg += command
          tmsg += "\x00" * (12 - len(command))
          tmsg += struct.pack("<I", len(data))
          if self.ver_send >= 209:
              th = sha256(data)
              h = sha256(th)
              tmsg += h[:4]
          tmsg += data
          with mininode_lock:
              self.sendbuf += tmsg
              self.last_sent = time.time()
  
      def got_message(self, message):
          if message.command == "version":
              if message.nVersion <= BIP0031_VERSION:
                  self.messagemap['ping'] = msg_ping_prebip31
          if self.last_sent + 30 * 60 < time.time():
              self.send_message(self.messagemap['ping']())
          self.show_debug_msg("Recv %s" % repr(message))
          self.cb.deliver(self, message)
  
      def disconnect_node(self):
          self.disconnect = True
  
  
  class NetworkThread(Thread):
      def run(self):
          while mininode_socket_map:
              # We check for whether to disconnect outside of the asyncore
              # loop to workaround the behavior of asyncore when using
              # select
              disconnected = []
              for fd, obj in mininode_socket_map.items():
                  if obj.disconnect:
                      disconnected.append(obj)
              [ obj.handle_close() for obj in disconnected ]
              asyncore.loop(0.1, use_poll=True, map=mininode_socket_map, count=1)
  
  
  # An exception we can raise if we detect a potential disconnect
  # (p2p or rpc) before the test is complete
  class EarlyDisconnectError(Exception):
      def __init__(self, value):
          self.value = value
  
      def __str__(self):
          return repr(self.value)
  