Add Xaya as new coin with basic chain handling (#889)

* Split out deserialisation of CAuxPow.

The current DeserializerAuxPow has code for reading a block header
including (potentially) an auxpow.  In this change, we split out the
logic for reading the actual CAuxPow instance to its own function.

This makes the code easier to read, as the different steps are more
clearly separated.  It will also be useful for working with CAuxPow
instances that are part of a different serialisation format (e.g.
for the Xaya blockchain).

* Add Xaya coin with deserialiser.

This defines a new coin for Xaya (https://github.com/xaya/xaya), with
the appropriate deserialiser methods.  Xaya is based on Namecoin, but
uses its own special twist on auxpow for the PoW, so we need to handle
that properly in block-header deserialisation.

Xaya also has names like Namecoin (but with slightly changed semantics),
but handling for them (i.e. building a name index in addition to the
address index) will be added later on.

* Keep more data in truncated Xaya headers.

When Xaya headers are truncated (because they are checkpointed), we still
need to send the algorithm and bits with them.  That is needed for the
difficulty retargeting of Xaya to work correctly.

* Define peers for Xaya.

We will run ElectrumX instances on the seeder VPSes.  Set those in PEERS
for mainnet (there are no peers for testnet).

electrumx/lib/coins.py

@@ -273,6 +273,7 @@ class AuxPowMixin(object):
     STATIC_BLOCK_HEADERS = False
     DESERIALIZER = lib_tx.DeserializerAuxPow
     SESSIONCLS = AuxPoWElectrumX
+    TRUNCATED_HEADER_SIZE = 80
     # AuxPoW headers are significantly larger, so the DEFAULT_MAX_SEND from
     # Bitcoin is insufficient.  In Namecoin mainnet, 5 MB wasn't enough to
     # sync, while 10 MB worked fine.
@@ -3177,3 +3178,56 @@ def header_hash(cls, header):
         '''Given a header return the hash.'''
         import cpupower
         return cpupower.getPoWHash(header)
+
+
+class Xaya(AuxPowMixin, Coin):
+    NAME = "Xaya"
+    SHORTNAME = "CHI"
+    NET = "mainnet"
+    XPUB_VERBYTES = bytes.fromhex("0488b21e")
+    XPRV_VERBYTES = bytes.fromhex("0488ade4")
+    P2PKH_VERBYTE = bytes.fromhex("1c")
+    P2SH_VERBYTES = [bytes.fromhex("1e")]
+    WIF_BYTE = bytes.fromhex("82")
+    GENESIS_HASH = ('e5062d76e5f50c42f493826ac9920b63'
+                    'a8def2626fd70a5cec707ec47a4c4651')
+    TX_COUNT = 1147749
+    TX_COUNT_HEIGHT = 1030000
+    TX_PER_BLOCK = 2
+    DESERIALIZER = lib_tx.DeserializerXaya
+    TRUNCATED_HEADER_SIZE = 80 + 5
+    RPC_PORT = 8396
+    PEERS = [
+        'seeder.xaya.io s50002',
+        'xaya.domob.eu s50002',
+    ]
+
+    @classmethod
+    def genesis_block(cls, block):
+        super().genesis_block(block)
+
+        # In Xaya, the genesis block's coinbase is spendable.  Thus unlike
+        # the generic genesis_block() method, we return the full block here.
+        return block
+
+
+class XayaTestnet(Xaya):
+    SHORTNAME = "XCH"
+    NET = "testnet"
+    P2PKH_VERBYTE = bytes.fromhex("58")
+    P2SH_VERBYTES = [bytes.fromhex("5a")]
+    WIF_BYTE = bytes.fromhex("e6")
+    GENESIS_HASH = ('5195fc01d0e23d70d1f929f21ec55f47'
+                    'e1c6ea1e66fae98ee44cbbc994509bba')
+    TX_COUNT = 51557
+    TX_COUNT_HEIGHT = 49000
+    TX_PER_BLOCK = 1
+    RPC_PORT = 18396
+    PEERS = []
+
+
+class XayaRegtest(XayaTestnet):
+    NET = "regtest"
+    GENESIS_HASH = ('6f750b36d22f1dc3d0a6e483af453010'
+                    '22646dfc3b3ba2187865f5a7d6d83ab1')
+    RPC_PORT = 18493

electrumx/lib/tx.py

@@ -275,28 +275,44 @@ def read_tx_and_vsize(self):
 class DeserializerAuxPow(Deserializer):
     VERSION_AUXPOW = (1 << 8)
 
+    def read_auxpow(self):
+        '''Reads and returns the CAuxPow data'''
+
+        # We first calculate the size of the CAuxPow instance and then
+        # read it as bytes in the final step.
+        start = self.cursor
+
+        self.read_tx()  # AuxPow transaction
+        self.cursor += 32  # Parent block hash
+        merkle_size = self._read_varint()
+        self.cursor += 32 * merkle_size  # Merkle branch
+        self.cursor += 4  # Index
+        merkle_size = self._read_varint()
+        self.cursor += 32 * merkle_size  # Chain merkle branch
+        self.cursor += 4  # Chain index
+        self.cursor += 80  # Parent block header
+
+        end = self.cursor
+        self.cursor = start
+        return self._read_nbytes(end - start)
+
     def read_header(self, static_header_size):
         '''Return the AuxPow block header bytes'''
+
+        # We are going to calculate the block size then read it as bytes
         start = self.cursor
+
         version = self._read_le_uint32()
         if version & self.VERSION_AUXPOW:
-            # We are going to calculate the block size then read it as bytes
             self.cursor = start
             self.cursor += static_header_size  # Block normal header
-            self.read_tx()  # AuxPow transaction
-            self.cursor += 32  # Parent block hash
-            merkle_size = self._read_varint()
-            self.cursor += 32 * merkle_size  # Merkle branch
-            self.cursor += 4  # Index
-            merkle_size = self._read_varint()
-            self.cursor += 32 * merkle_size  # Chain merkle branch
-            self.cursor += 4  # Chain index
-            self.cursor += 80  # Parent block header
+            self.read_auxpow()
             header_end = self.cursor
         else:
-            header_end = static_header_size
+            header_end = start + static_header_size
+
         self.cursor = start
-        return self._read_nbytes(header_end)
+        return self._read_nbytes(header_end - start)
 
 
 class DeserializerAuxPowSegWit(DeserializerSegWit, DeserializerAuxPow):
@@ -918,3 +934,37 @@ def _read_input(self):
             )
 
         return tx_input
+
+
+class DeserializerXaya(DeserializerSegWit, DeserializerAuxPow):
+    """Deserializer class for the Xaya network
+
+    The main difference to other networks is the changed format of the
+    block header with "triple purpose mining", see
+    https://github.com/xaya/xaya/blob/master/doc/xaya/mining.md.
+
+    This builds upon classic auxpow, but has a modified serialisation format
+    that we have to implement here."""
+
+    MM_FLAG = 0x80
+
+    def read_header(self, static_header_size):
+        """Reads in the full block header (including PoW data)"""
+
+        # We first calculate the dynamic size of the block header, and then
+        # read in all the data in the final step.
+        start = self.cursor
+
+        self.cursor += static_header_size  # Normal block header
+
+        algo = self._read_byte()
+        self._read_le_uint32()  # nBits
+
+        if algo & self.MM_FLAG:
+            self.read_auxpow()
+        else:
+            self.cursor += static_header_size  # Fake header
+
+        end = self.cursor
+        self.cursor = start
+        return self._read_nbytes(end - start)

electrumx/server/session.py

@@ -1680,7 +1680,7 @@ def truncate_auxpow(self, headers_full_hex, start_height):
         headers = bytearray()
 
         while cursor < len(headers_full):
-            headers.extend(headers_full[cursor:cursor+self.coin.BASIC_HEADER_SIZE])
+            headers.extend(headers_full[cursor:cursor+self.coin.TRUNCATED_HEADER_SIZE])
             cursor += self.db.dynamic_header_len(height)
             height += 1
 

tests/blocks/xaya_mainnet_neoscrypt_400021.json

@@ -0,0 +1,31 @@
+{
+  "hash": "c53c371f253426f9e582e3de9d9f1f03e5e40e771aa96953c502ebe2222bb013",
+  "confirmations": 630231,
+  "strippedsize": 582,
+  "size": 618,
+  "weight": 2364,
+  "height": 400021,
+  "version": 536870912,
+  "versionHex": "20000000",
+  "merkleroot": "28e89aa0dbc0f1cacccb3ab402d7891abf636165b2cfd1b018e3b675468d8855",
+  "tx": [
+    "43b8bea316ac7df3eeadd3b941808b100d66d424464af2dfb211773cd8dc0752",
+    "4d581281a17e679df9f109e0b0e7c59efacfe50860a733d1f06a23fa08540b6d"
+  ],
+  "time": 1544070336,
+  "mediantime": 1544070221,
+  "nonce": 0,
+  "chainwork": "00000000000000000000000000000000000000000011cc010c812da27182ad31",
+  "nTx": 2,
+  "powdata": {
+    "algo": "neoscrypt",
+    "mergemined": false,
+    "bits": "1d016293",
+    "difficulty": 0.7219816901873947,
+    "fakeheader": "00000000000000000000000000000000000000000000000000000000000000000000000013b02b22e2eb02c55369a91a770ee4e5031f9f9ddee382e5f92634251f373cc50000000000000000cd8740e3"
+  },
+  "rngseed": "ae81fb25abb6328512e52af04b7e36e03ed545061ad000e6b07ed86e08551cb1",
+  "previousblockhash": "ab66782b9aa7edd86912bde739b7954517ef82907e7df2b910c6720b69c197fb",
+  "nextblockhash": "adfaac85095ab7f6c565a4c7af76229abcfd07fb0a0199383c3d65b5294f471a",
+  "block": "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"
+}

tests/blocks/xaya_mainnet_sha256d_100000.json

@@ -0,0 +1,103 @@
+{
+  "hash": "948183fa76c2a4466bb32a06cc4f4f0afe3894d524dd07a963b3836c092f3acd",
+  "confirmations": 930248,
+  "strippedsize": 1567,
+  "size": 1603,
+  "weight": 6304,
+  "height": 100000,
+  "version": 536870912,
+  "versionHex": "20000000",
+  "merkleroot": "bd2b4a5a8f1f8085bab936f2f20f82e5928a0bbd573be780fec14d8b4fc4e922",
+  "tx": [
+    "e16a22c4dfd99c639b60914ce75e3a7847fed7c1f3f5f2dd565ff48d6395a116",
+    "9854b65e59dca27649a3268d0feee2d55036e26cc49038f67aae000dd0126b48"
+  ],
+  "time": 1534624527,
+  "mediantime": 1534624309,
+  "nonce": 0,
+  "chainwork": "00000000000000000000000000000000000000000003fbc9da84e345e04f5136",
+  "nTx": 2,
+  "powdata": {
+    "algo": "sha256d",
+    "mergemined": true,
+    "bits": "18347258",
+    "difficulty": 20964060431.07306,
+    "auxpow": {
+      "tx": {
+        "hex": "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",
+        "txid": "54bfbec36774378ce65ab829b00d45bb4d734a9220932f5514d8b4e1992e8dfc",
+        "hash": "54bfbec36774378ce65ab829b00d45bb4d734a9220932f5514d8b4e1992e8dfc",
+        "version": 1,
+        "size": 294,
+        "vsize": 294,
+        "weight": 1176,
+        "locktime": 1205115995,
+        "vin": [
+          {
+            "coinbase": "033c33082cfabe6d6dfe0718afd8c0651b58f14378a128efde085d91bcfa2790de57ec862ad420d90708000000f09f909f000f4d696e6564206279207374636f646500000000000000000000000000000000000000000000000000000000000000000000",
+            "sequence": 26885119
+          }
+        ],
+        "vout": [
+          {
+            "value": 12.62196768,
+            "n": 0,
+            "scriptPubKey": {
+              "asm": "OP_DUP OP_HASH160 c825a1ecf2a6830c4401620c3a16f1995057c2ab OP_EQUALVERIFY OP_CHECKSIG",
+              "hex": "76a914c825a1ecf2a6830c4401620c3a16f1995057c2ab88ac",
+              "reqSigs": 1,
+              "type": "pubkeyhash",
+              "addresses": [
+                "CaiAoAHC4kYmGJnNdcJWP8EFDE42Ji7XiS"
+              ]
+            }
+          },
+          {
+            "value": 0.00000000,
+            "n": 1,
+            "scriptPubKey": {
+              "asm": "OP_RETURN aa21a9ed98a08f4c63b7cad2f139005520cf5998e1fa2ad8d53bbad87e0868d8c5091493 0000000000000000",
+              "hex": "6a24aa21a9ed98a08f4c63b7cad2f139005520cf5998e1fa2ad8d53bbad87e0868d8c5091493080000000000000000",
+              "type": "nulldata"
+            }
+          },
+          {
+            "value": 0.00000000,
+            "n": 2,
+            "scriptPubKey": {
+              "asm": "OP_RETURN 52534b424c4f434b3a88b841b4ba9c30eff483b55f8a520403afac9e2050a769129a76620c51e63361",
+              "hex": "6a4c2952534b424c4f434b3a88b841b4ba9c30eff483b55f8a520403afac9e2050a769129a76620c51e63361",
+              "type": "nulldata"
+            }
+          }
+        ],
+        "blockhash": "00000000000000001903108b258887d0258a3e8caf776983069f94b9f47049f6"
+      },
+      "chainindex": 7,
+      "merklebranch": [
+        "5c3158d4f108917fba77f9695650608477456b8f6f06238b1613311aafa74b09",
+        "eebaf1b6b9ab455497e6dd571140f0a3647ce36e1ab3e34a177dacc474a755d9",
+        "69191fcf85cf624ec99de2d341475478d5b4dc6ba47fc615aaefb05af2ca27a8",
+        "4930ddee5d4553184fc83c98e86f3fb317e6811c00840789dc67fea8be9a182f",
+        "32648a287897e297e999fff9426c2b90b79bf7d1b086a227a19b13a7ec2b41a2",
+        "fffd55d7bbea5f951ae2f3a8f540a9a0a71949d9578d9d44d20f86e090a2f810",
+        "74ddee1ce47dcb62229411fe9ae3a208f488ed18aef409fb5704fb55844ce2e0",
+        "a3b018da9723bdef26aaf35c69c24ef03c028ef0080cb78f524de8a3f1ae4ef4",
+        "b2b0fee71fab43ae9c6eb27aaff5f4a1806a3568a0fd7cdae67c95b7f5684ce2",
+        "ca7503900f2b8aeec18402721788f9ea340ab4216ffd095cba066b3af306cbdb",
+        "0aba5a93156602ce5202293e3c83c4e1f3c754ff9338770d18bceda4fcfbd686",
+        "084cf897b58d851626d0ba32d4c717584b018881ab022e8fba1c9d8ed6aaae0e"
+      ],
+      "chainmerklebranch": [
+        "2cadbb3ce34769fc6f95572012c22605f8c3a69982a9a6854523f6548007d30b",
+        "e5c2407ba454ffeb28cf0c50c5c293a84c9a75788f8a8f35ccb974e606280377",
+        "a5cd51355bea0fd77416d06bf3647e16b4663d2f87e6a3ccb23e713cb8b4de1c"
+      ],
+      "parentblock": "00000020913d01444f14db2c6ab43ffd0f36af5613423815543c22000000000000000000a2edf8bab99ac19e7f7adaf23bc43570d543054aed83e77694f26d33ec9db2a51e83785ba70d2c17865f3a57"
+    }
+  },
+  "rngseed": "1cc1ed830b99a352c02a10fca08284d005c1cfb01e5ffd10b85bcda3e2164636",
+  "previousblockhash": "8acbc6b31dabb5b3a224d9e4e55e2bd766882f07b2c592e1a101ab7a6e59cd6b",
+  "nextblockhash": "427b1860366cfc584170f73b0518a71adb9787841c960ad3a857e27b6b773385",
+  "block": "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"
+}

tests/test_blocks.py

@@ -66,5 +66,6 @@ def test_block(block_details):
         block.header) == hex_str_to_hash(block_info['hash'])
     assert (coin.header_prevhash(block.header)
             == hex_str_to_hash(block_info['previousblockhash']))
+    assert len(block_info['tx']) == len(block.transactions)
     for n, (tx, txid) in enumerate(block.transactions):
         assert txid == hex_str_to_hash(block_info['tx'][n])

tests/test_transactions.py

@@ -56,8 +56,12 @@ def test_transaction(transaction_details):
         spk = vout[i]['scriptPubKey']
         tx_pks = tx.outputs[i].pk_script
         assert spk['hex'] == tx_pks.hex()
-        assert coin.address_to_hashX(spk['address']) == \
-               coin.hashX_from_script(tx_pks)
+        if "addresses" in spk:
+            assert len(spk["addresses"]) == 1
+            address = spk["addresses"][0]
+        else:
+            address = spk["address"]
+        assert coin.address_to_hashX(address) == coin.hashX_from_script(tx_pks)
         if issubclass(coin, Namecoin):
             if "nameOp" not in spk or "name" not in spk["nameOp"]:
                 assert coin.name_hashX_from_script(tx_pks) is None