Added Zencash supporting

trezorctl

@@ -576,6 +576,10 @@ def sign_tx(connect, coin):
         sequence = click.prompt('Sequence Number to use (RBF opt-in enabled by default)', type=int, default=0xfffffffd)
         script_type = click.prompt('Input type', type=CHOICE_INPUT_SCRIPT_TYPE, default=default_script_type(address_n))
         script_type = script_type if isinstance(script_type, int) else CHOICE_INPUT_SCRIPT_TYPE.typemap[script_type]
+        if txapi.bip115:
+            prev_output = txapi.get_tx(binascii.hexlify(prev_hash).decode("utf-8")).bin_outputs[prev_index]
+            prev_blockhash = prev_output.block_hash
+            prev_blockheight = prev_output.block_height
         inputs.append(proto.TxInputType(
             address_n=address_n,
             prev_hash=prev_hash,
@@ -583,8 +587,15 @@ def sign_tx(connect, coin):
             amount=amount,
             script_type=script_type,
             sequence=sequence,
+            prev_block_hash_bip115=prev_blockhash,
+            prev_block_height_bip115=prev_blockheight,
         ))
 
+    if txapi.bip115:
+        current_block_height = txapi.current_height()
+        block_height = current_block_height - 300  # Zencash recommendation for the better protection
+        block_hash = txapi.get_block_hash(block_height)
+
     outputs = []
     while True:
         click.echo()
@@ -604,6 +615,8 @@ def sign_tx(connect, coin):
             address=address,
             amount=amount,
             script_type=script_type,
+            block_hash_bip115=block_hash[::-1],  # Blockhash passed in reverse order
+            block_height_bip115=block_height
         ))
 
     tx_version = click.prompt('Transaction version', type=int, default=2)

trezorlib/coins.py

@@ -39,8 +39,9 @@ def _insight_for_coin(coin):
     if not url:
         return None
     zcash = coin['coin_name'].lower().startswith('zcash')
+    bip115 = coin['bip115']
     network = 'insight_{}'.format(coin['coin_name'].lower().replace(' ', '_'))
-    return TxApiInsight(network=network, url=url, zcash=zcash)
+    return TxApiInsight(network=network, url=url, zcash=zcash, bip115=bip115)
 
 
 # exported variables

trezorlib/tests/unit_tests/test_tx_api.py

@@ -18,9 +18,11 @@ import os
 
 from trezorlib import coins
 from trezorlib import tx_api
+import binascii
 
 TxApiBitcoin = coins.tx_api['Bitcoin']
 TxApiTestnet = tx_api.TxApiInsight("insight_testnet")
+TxApiZencash = coins.tx_api['Zencash']
 
 tests_dir = os.path.dirname(os.path.abspath(__file__))
 
@@ -42,3 +44,13 @@ def test_tx_api_gettx():
 
     TxApiTestnet.get_tx('6f90f3c7cbec2258b0971056ef3fe34128dbde30daa9c0639a898f9977299d54')
     TxApiTestnet.get_tx('d6da21677d7cca5f42fbc7631d062c9ae918a0254f7c6c22de8e8cb7fd5b8236')
+
+
+def test_tx_api_current_block():
+    height = TxApiZencash.current_height()
+    assert height > 347041
+
+
+def test_tx_api_get_block_hash():
+    hash = TxApiZencash.get_block_hash(110000)
+    assert hash == binascii.unhexlify('000000003f5d6ba1385c6cd2d4f836dfc5adf7f98834309ad67e26faef462454')

trezorlib/tx_api.py

@@ -33,6 +33,18 @@ class TxApi(object):
         url = '%s%s/%s' % (self.url, resource, resourceid)
         return url
 
+    def current_height(self):
+        r = requests.get(self.url + '/status?q=getBlockCount')
+        j = r.json(parse_float=str)
+        block_height = j['info']['blocks']
+        return block_height
+
+    def get_block_hash(self, block_number):
+        r = requests.get(self.url + '/block-index/' + str(block_number))
+        j = r.json(parse_float=str)
+        block_hash = binascii.unhexlify(j['blockHash'])
+        return block_hash
+
     def fetch_json(self, resource, resourceid):
         global cache_dir
         if cache_dir:
@@ -65,11 +77,13 @@ class TxApi(object):
 
 class TxApiInsight(TxApi):
 
-    def __init__(self, network, url=None, zcash=None):
+    def __init__(self, network, url=None, zcash=None, bip115=False):
         super().__init__(network, url)
         self.zcash = zcash
+        self.bip115 = bip115
         if url:
-            self.pushtx_url = url.replace('/api/', '/tx/send')
+            prefix, suffix = url.rsplit('/', maxsplit=1)
+            self.pushtx_url = prefix + '/tx/send'
 
     def get_tx(self, txhash):
 
@@ -97,6 +111,12 @@ class TxApiInsight(TxApi):
             o = t._add_bin_outputs()
             o.amount = int(Decimal(vout['value']) * 100000000)
             o.script_pubkey = binascii.unhexlify(vout['scriptPubKey']['hex'])
+            if self.bip115 and o.script_pubkey[-1] == 0xb4:
+                # Verify if coin implements replay protection bip115 and script includes checkblockatheight opcode. 0xb4 - is op_code (OP_CHECKBLOCKATHEIGHT)
+                # <OP_32> <32-byte block hash> <OP_3> <3-byte block height> <OP_CHECKBLOCKATHEIGHT>
+                tail = o.script_pubkey[-38:]
+                o.block_hash = tail[1:33]  # <32-byte block hash>
+                o.block_height = int.from_bytes(tail[34:37], byteorder='little')  # <3-byte block height>
 
         if self.zcash:
             t.overwintered = data.get('fOverwintered', False)