Check Genesis hash

Testnet RPC_PORT is 18332

lib/coins.py

@@ -22,7 +22,7 @@ import sys
 from lib.hash import Base58, hash160, ripemd160, double_sha256, hash_to_str
 from lib.script import ScriptPubKey
 from lib.tx import Deserializer, DeserializerSegWit
-from lib.util import cachedproperty, subclasses
+import lib.util as util
 
 
 class CoinError(Exception):
@@ -46,7 +46,7 @@ class Coin(object):
         '''Return a coin class given name and network.
 
         Raise an exception if unrecognised.'''
-        for coin in subclasses(Coin):
+        for coin in util.subclasses(Coin):
             if (coin.NAME.lower() == name.lower()
                     and coin.NET.lower() == net.lower()):
                 return coin
@@ -70,6 +70,20 @@ class Coin(object):
     def daemon_urls(cls, urls):
         return [cls.sanitize_url(url) for url in urls.split(',')]
 
+    @classmethod
+    def genesis_block(cls, block):
+        '''Check the Genesis block is the right one for this coin.
+
+        Return the block less its unspendable coinbase.
+        '''
+        header = block[:cls.header_len(0)]
+        header_hex_hash = hash_to_str(cls.header_hash(header))
+        if header_hex_hash != cls.GENESIS_HASH:
+            raise CoinError('genesis block has hash {} expected {}'
+                            .format(header_hex_hash, cls.GENESIS_HASH))
+
+        return header + bytes(1)
+
     @classmethod
     def hashX_from_script(cls, script):
         '''Returns a hashX from a script.'''
@@ -78,7 +92,7 @@ class Coin(object):
             return None
         return sha256(script).digest()[:cls.HASHX_LEN]
 
-    @cachedproperty
+    @util.cachedproperty
     def address_handlers(cls):
         return ScriptPubKey.PayToHandlers(
             address = cls.P2PKH_address_from_hash160,
@@ -251,8 +265,8 @@ class Bitcoin(Coin):
     P2PKH_VERBYTE = 0x00
     P2SH_VERBYTE = 0x05
     WIF_BYTE = 0x80
-    GENESIS_HASH=(b'000000000019d6689c085ae165831e93'
-                  b'4ff763ae46a2a6c172b3f1b60a8ce26f')
+    GENESIS_HASH=('000000000019d6689c085ae165831e93'
+                  '4ff763ae46a2a6c172b3f1b60a8ce26f')
     TX_COUNT = 156335304
     TX_COUNT_HEIGHT = 429972
     TX_PER_BLOCK = 1800
@@ -269,13 +283,14 @@ class BitcoinTestnet(Bitcoin):
     P2PKH_VERBYTE = 0x6f
     P2SH_VERBYTE = 0xc4
     WIF_BYTE = 0xef
-    GENESIS_HASH=(b'000000000933ea01ad0ee984209779ba'
-                  b'aec3ced90fa3f408719526f8d77f4943')
+    GENESIS_HASH=('000000000933ea01ad0ee984209779ba'
+                  'aec3ced90fa3f408719526f8d77f4943')
     REORG_LIMIT = 2000
     TX_COUNT = 12242438
     TX_COUNT_HEIGHT = 1035428
     TX_PER_BLOCK = 21
     IRC_PREFIX = "ET_"
+    RPC_PORT = 18332
 
 
 class BitcoinTestnetSegWit(BitcoinTestnet):
@@ -300,8 +315,8 @@ class Litecoin(Coin):
     P2PKH_VERBYTE = 0x30
     P2SH_VERBYTE = 0x05
     WIF_BYTE = 0xb0
-    GENESIS_HASH=(b'000000000019d6689c085ae165831e93'
-                  b'4ff763ae46a2a6c172b3f1b60a8ce26f')
+    GENESIS_HASH=('000000000019d6689c085ae165831e93'
+                  '4ff763ae46a2a6c172b3f1b60a8ce26f')
     TX_COUNT = 8908766
     TX_COUNT_HEIGHT = 1105256
     TX_PER_BLOCK = 10
@@ -375,8 +390,8 @@ class Dash(Coin):
     NET = "mainnet"
     XPUB_VERBYTES = bytes.fromhex("02fe52cc")
     XPRV_VERBYTES = bytes.fromhex("02fe52f8")
-    GENESIS_HASH = (b'00000ffd590b1485b3caadc19b22e637'
-                    b'9c733355108f107a430458cdf3407ab6')
+    GENESIS_HASH = ('00000ffd590b1485b3caadc19b22e637'
+                    '9c733355108f107a430458cdf3407ab6')
     P2PKH_VERBYTE = 0x4c
     P2SH_VERBYTE = 0x10
     WIF_BYTE = 0xcc
@@ -398,8 +413,8 @@ class DashTestnet(Dash):
     NET = "testnet"
     XPUB_VERBYTES = bytes.fromhex("3a805837")
     XPRV_VERBYTES = bytes.fromhex("3a8061a0")
-    GENESIS_HASH = (b'00000bafbc94add76cb75e2ec9289483'
-                    b'7288a481e5c005f6563d91623bf8bc2c')
+    GENESIS_HASH = ('00000bafbc94add76cb75e2ec9289483'
+                    '7288a481e5c005f6563d91623bf8bc2c')
     P2PKH_VERBYTE = 0x8c
     P2SH_VERBYTE = 0x13
     WIF_BYTE = 0xef

server/block_processor.py

@@ -125,9 +125,11 @@ class Prefetcher(LoggedClass):
 
                 assert count == len(blocks)
 
-                # Strip the unspendable genesis coinbase
+                # Special handling for genesis block
                 if first == 0:
-                    blocks[0] = blocks[0][:self.coin.header_len(0)] + bytes(1)
+                    blocks[0] = self.coin.genesis_block(blocks[0])
+                    self.logger.info('verified genesis block with hash {}'
+                                     .format(hex_hashes[0]))
 
                 # Update our recent average block size estimate
                 size = sum(len(block) for block in blocks)

server/db.py

@@ -142,7 +142,11 @@ class DB(util.LoggedClass):
                 raise self.DBError('your DB version is {} but this software '
                                    'only handles versions {}'
                                    .format(self.db_version, self.DB_VERSIONS))
-            if state['genesis'] != self.coin.GENESIS_HASH:
+            # backwards compat
+            genesis_hash = state['genesis']
+            if isinstance(genesis_hash, bytes):
+                genesis_hash = genesis_hash.decode()
+            if genesis_hash != self.coin.GENESIS_HASH:
                 raise self.DBError('DB genesis hash {} does not match coin {}'
                                    .format(state['genesis_hash'],
                                            self.coin.GENESIS_HASH))