Add TokenPay (#495)

This commit adds TokenPay as a supported coin.

.travis.yml

@@ -29,6 +29,7 @@ install:
 # hashes
   - pip install tribus-hash
   - pip install blake256
+  - pip install scrypt
   - pip install x11_hash
   - pip install xevan_hash
   - pip install quark_hash

electrumx/lib/coins.py

@@ -1174,6 +1174,31 @@ class Reddcoin(Coin):
     RPC_PORT = 45443
 
 
+class TokenPay(ScryptMixin, Coin):
+    NAME = "TokenPay"
+    SHORTNAME = "TPAY"
+    NET = "mainnet"
+    P2PKH_VERBYTE = bytes.fromhex("41")
+    P2SH_VERBYTES = [bytes.fromhex("7e")]
+    WIF_BYTE = bytes.fromhex("b3")
+    GENESIS_HASH = ('000008b71ab32e585a23f0de642dc113'
+                    '740144e94c0ece047751e9781f953ae9')
+    DESERIALIZER = lib_tx.DeserializerTokenPay
+    DAEMON = daemon.LegacyRPCDaemon
+    TX_COUNT = 147934
+    TX_COUNT_HEIGHT = 73967
+    TX_PER_BLOCK = 100
+    RPC_PORT = 8800
+    REORG_LIMIT = 500
+    XPUB_VERBYTES = bytes.fromhex("0488B21E")
+    XPRV_VERBYTES = bytes.fromhex("0488ADE4")
+
+    PEERS = [
+        "electrum-us.tpay.ai s",
+        "electrum-eu.tpay.ai s",
+    ]
+
+
 class Vertcoin(Coin):
     NAME = "Vertcoin"
     SHORTNAME = "VTC"

electrumx/lib/tx.py

@@ -30,6 +30,7 @@
 from collections import namedtuple
 
 from electrumx.lib.hash import sha256, double_sha256, hash_to_hex_str
+from electrumx.lib.script import OpCodes
 from electrumx.lib.util import (
     unpack_le_int32_from, unpack_le_int64_from, unpack_le_uint16_from,
     unpack_le_uint32_from, unpack_le_uint64_from, pack_le_int32, pack_varint,
@@ -422,6 +423,74 @@ class DeserializerGroestlcoin(DeserializerSegWit):
     TX_HASH_FN = staticmethod(sha256)
 
 
+class TxInputTokenPay(TxInput):
+    '''Class representing a TokenPay transaction input.'''
+
+    OP_ANON_MARKER = 0xb9
+    # 2byte marker (cpubkey + sigc + sigr)
+    MIN_ANON_IN_SIZE = 2 + (33 + 32 + 32)
+
+    def _is_anon_input(self):
+        return (len(self.script) >= self.MIN_ANON_IN_SIZE and
+                self.script[0] == OpCodes.OP_RETURN and
+                self.script[1] == self.OP_ANON_MARKER)
+
+    def is_generation(self):
+        # Transactions comming in from stealth addresses are seen by
+        # the blockchain as newly minted coins. The reverse, where coins
+        # are sent TO a stealth address, are seen by the blockchain as
+        # a coin burn.
+        if self._is_anon_input():
+            return True
+        return super(TxInputTokenPay, self).is_generation()
+
+
+class TxInputTokenPayStealth(
+        namedtuple("TxInput", "keyimage ringsize script sequence")):
+    '''Class representing a TokenPay stealth transaction input.'''
+
+    def __str__(self):
+        script = self.script.hex()
+        keyimage = bytes(self.keyimage).hex()
+        return ("Input({}, {:d}, script={}, sequence={:d})"
+                .format(keyimage, self.ringsize[1], script, self.sequence))
+
+    def is_generation(self):
+        return True
+
+    def serialize(self):
+        return b''.join((
+            self.keyimage,
+            self.ringsize,
+            pack_varbytes(self.script),
+            pack_le_uint32(self.sequence),
+        ))
+
+
+class DeserializerTokenPay(DeserializerTxTime):
+
+    def _read_input(self):
+        txin = TxInputTokenPay(
+            self._read_nbytes(32),   # prev_hash
+            self._read_le_uint32(),  # prev_idx
+            self._read_varbytes(),   # script
+            self._read_le_uint32(),  # sequence
+        )
+        if txin._is_anon_input():
+            # Not sure if this is actually needed, and seems
+            # extra work for no immediate benefit, but it at
+            # least correctly represents a stealth input
+            raw = txin.serialize()
+            deserializer = Deserializer(raw)
+            txin = TxInputTokenPayStealth(
+                deserializer._read_nbytes(33),  # keyimage
+                deserializer._read_nbytes(3),   # ringsize
+                deserializer._read_varbytes(),  # script
+                deserializer._read_le_uint32()  # sequence
+            )
+        return txin
+
+
 # Decred
 class TxInputDcr(namedtuple("TxInput", "prev_hash prev_idx tree sequence")):
     '''Class representing a Decred transaction input.'''

tests/blocks/tokenpay_mainnet_20000.json

@@ -0,0 +1,28 @@
+{
+    "hash" : "a04c982af88368f934aada4c04a2907c204548b2f23b123104e5d5681318c58e",
+    "confirmations" : 223761,
+    "size" : 400,
+    "height" : 20000,
+    "version" : 6,
+    "merkleroot" : "9a15ca74bc6caf91be0517be05236a2c013993bbd9c0b28fd61dacbe66ff0edb",
+    "mint" : 0.06584667,
+    "time" : 1517342128,
+    "nonce" : 0,
+    "bits" : "1e00857c",
+    "difficulty" : 0.00749140,
+    "blocktrust" : "1eaf6bd",
+    "chaintrust" : "376cd8e0ac",
+    "previousblockhash" : "03e5e53d9edacc59720e22800f9f0230b7100abd1c2f388c64a2e0bd98df2710",
+    "nextblockhash" : "caff0ac56f5b367dc4f4da3d2b4a8848d4116079c353234ab2e0fe6f3f69ff82",
+    "flags" : "proof-of-stake",
+    "proofhash" : "000019d0fa709575179a07d46604f5d4efbf7bb02b5a1308b6a9f4410ba3328e",
+    "entropybit" : 0,
+    "modifier" : "1c5a2302bda4c0f3",
+    "modifierv2" : "5740fb0cc8bf2853ad258f16c363bbb92387cf85ac874ec553917c903ea70444",
+    "tx" : [
+        "d2e1100088af3e19976cac83f167ceffe725375442907d739341a40896d1089c",
+        "c24b1208937b6f634c0410cbc9ecf00a36837451ae27a85550b6af2a35b36f1f"
+    ],
+    "signature" : "304402206d29ae84b3d1e6ac4cafefee9aaf8b96a5b2c1d60fa43f8805916db72e47e90502203aed70e4cf36ecd5f07d01087e8c7bc9b232825204116c6e2f77875ce0480f68",
+    "block": "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"
+}

tests/lib/test_addresses.py

@@ -64,7 +64,9 @@ addresses = [
     (coins.PivxTestnet, "yJ8iHtUxj9U4vsXLCZTbPNbuxG6NJNCvb8",
      "e808105b7bfcc8b102cafa7242089b22c77a3b94", "31d61c3076fa0b2b7c74ef"),
     (coins.PivxTestnet, "yCcNWqqMhDmsPzKchCPK1ux4HpxK7j3xpB",
-     "ab72728952c06dfc0f6cf21449dd645422731ec4", "eb3a3155215538d51de7cc")
+     "ab72728952c06dfc0f6cf21449dd645422731ec4", "eb3a3155215538d51de7cc"),
+    (coins.TokenPay, "TDE2X28FGtckatxuP3d8s3V726G4TLNHpT",
+     "23b5dd9b7b402388c7a40bc88c261f3178acf30d", "7c7bdf0e0713f3752f4b88"),
 ]
 
 

tests/server/test_env.py

@@ -134,7 +134,10 @@ def test_COIN_NET():
     e = Env()
     assert e.coin == lib_coins.PivxTestnet
     os.environ.pop('NET')
-
+    os.environ['NET'] = 'mainnet'
+    os.environ['COIN'] = ' TokenPay '
+    e = Env()
+    assert e.coin == lib_coins.TokenPay
 
 def test_CACHE_MB():
     assert_integer('CACHE_MB', 'cache_MB', 1200)