core/sign_tx: Derive Zip143 and DecredPrefixHasher from Bip143.

core/src/apps/wallet/sign_tx/decred.py

@@ -13,6 +13,7 @@ from trezor.utils import HashWriter, ensure
 
 from apps.common import coininfo, seed
 from apps.wallet.sign_tx import addresses, helpers, multisig, progress, scripts, writers
+from apps.wallet.sign_tx.segwit_bip143 import Bip143
 from apps.wallet.sign_tx.signing import Bitcoin, SigningError, ecdsa_sign
 
 DECRED_SERIALIZE_FULL = const(0 << 16)
@@ -25,7 +26,7 @@ if False:
     from typing import Union
 
 
-class DecredPrefixHasher:
+class DecredPrefixHasher(Bip143):
     """
     While Decred does not have the exact same implementation as bip143/zip143,
     the semantics for using the prefix hash of transactions are close enough
@@ -53,7 +54,7 @@ class DecredPrefixHasher:
         writers.write_uint32(self.h_prefix, tx.lock_time)
         writers.write_uint32(self.h_prefix, tx.expiry)
 
-    def prefix_hash(self) -> bytes:
+    def get_prefix_hash(self) -> bytes:
         return self.h_prefix.get_digest()
 
 
@@ -110,7 +111,7 @@ class Decred(Bitcoin):
     async def phase2(self) -> None:
         self.tx_req.serialized = None
 
-        prefix_hash = self.hash143.prefix_hash()
+        prefix_hash = self.hash143.get_prefix_hash()
 
         for i_sign in range(self.tx.inputs_count):
             progress.advance()

core/src/apps/wallet/sign_tx/segwit_bip143.py

@@ -37,9 +37,15 @@ class Bip143:
     def add_sequence(self, txi: TxInputType) -> None:
         write_uint32(self.h_sequence, txi.sequence)
 
+    def add_output_count(self, tx: SignTx) -> None:
+        pass
+
     def add_output(self, txo_bin: TxOutputBinType) -> None:
         write_tx_output(self.h_outputs, txo_bin)
 
+    def add_locktime_expiry(self, tx: SignTx) -> None:
+        pass
+
     def get_prevouts_hash(self, coin: CoinInfo) -> bytes:
         return get_tx_hash(self.h_prevouts, double=coin.sign_hash_double)
 
@@ -49,6 +55,9 @@ class Bip143:
     def get_outputs_hash(self, coin: CoinInfo) -> bytes:
         return get_tx_hash(self.h_outputs, double=coin.sign_hash_double)
 
+    def get_prefix_hash(self) -> bytes:
+        pass
+
     def preimage_hash(
         self,
         coin: CoinInfo,
@@ -70,7 +79,7 @@ class Bip143:
         write_bytes_reversed(h_preimage, txi.prev_hash, TX_HASH_SIZE)  # outpoint
         write_uint32(h_preimage, txi.prev_index)  # outpoint
 
-        script_code = self.derive_script_code(txi, pubkeyhash)  # scriptCode
+        script_code = derive_script_code(txi, pubkeyhash)  # scriptCode
         write_bytes_prefixed(h_preimage, script_code)
 
         write_uint64(h_preimage, txi.amount)  # amount
@@ -82,9 +91,10 @@ class Bip143:
 
         return get_tx_hash(h_preimage, double=coin.sign_hash_double)
 
-    # see https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki#specification
+
-    # item 5 for details
+# see https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki#specification
-    def derive_script_code(self, txi: TxInputType, pubkeyhash: bytes) -> bytearray:
+# item 5 for details
+def derive_script_code(txi: TxInputType, pubkeyhash: bytes) -> bytearray:
 
     if txi.multisig:
         return output_script_multisig(
@@ -103,6 +113,5 @@ class Bip143:
 
     else:
         raise Bip143Error(
-                FailureType.DataError,
+            FailureType.DataError, "Unknown input script type for bip143 script code",
-                "Unknown input script type for bip143 script code",
         )

core/src/apps/wallet/sign_tx/zcash.py

@@ -6,7 +6,6 @@ from trezor.messages import FailureType, InputScriptType
 from trezor.messages.SignTx import SignTx
 from trezor.messages.TransactionType import TransactionType
 from trezor.messages.TxInputType import TxInputType
-from trezor.messages.TxOutputBinType import TxOutputBinType
 from trezor.utils import HashWriter, ensure
 
 from apps.common.coininfo import CoinInfo
@@ -14,6 +13,7 @@ from apps.common.seed import Keychain
 from apps.wallet.sign_tx.bitcoinlike import Bitcoinlike
 from apps.wallet.sign_tx.multisig import multisig_get_pubkeys
 from apps.wallet.sign_tx.scripts import output_script_multisig, output_script_p2pkh
+from apps.wallet.sign_tx.segwit_bip143 import Bip143
 from apps.wallet.sign_tx.signing import SigningError
 from apps.wallet.sign_tx.writers import (
     TX_HASH_SIZE,
@@ -21,7 +21,6 @@ from apps.wallet.sign_tx.writers import (
     write_bytes_fixed,
     write_bytes_prefixed,
     write_bytes_reversed,
-    write_tx_output,
     write_uint32,
     write_uint64,
     write_varint,
@@ -55,30 +54,20 @@ def derive_script_code(txi: TxInputType, pubkeyhash: bytes) -> bytearray:
         )
 
 
-class Zip143:
+class Zip143(Bip143):
     def __init__(self, branch_id: int) -> None:
         self.branch_id = branch_id
         self.h_prevouts = HashWriter(blake2b(outlen=32, personal=b"ZcashPrevoutHash"))
         self.h_sequence = HashWriter(blake2b(outlen=32, personal=b"ZcashSequencHash"))
         self.h_outputs = HashWriter(blake2b(outlen=32, personal=b"ZcashOutputsHash"))
 
-    def add_prevouts(self, txi: TxInputType) -> None:
+    def get_prevouts_hash(self, coin: CoinInfo) -> bytes:
-        write_bytes_reversed(self.h_prevouts, txi.prev_hash, TX_HASH_SIZE)
-        write_uint32(self.h_prevouts, txi.prev_index)
-
-    def add_sequence(self, txi: TxInputType) -> None:
-        write_uint32(self.h_sequence, txi.sequence)
-
-    def add_output(self, txo_bin: TxOutputBinType) -> None:
-        write_tx_output(self.h_outputs, txo_bin)
-
-    def get_prevouts_hash(self) -> bytes:
         return get_tx_hash(self.h_prevouts)
 
-    def get_sequence_hash(self) -> bytes:
+    def get_sequence_hash(self, coin: CoinInfo) -> bytes:
         return get_tx_hash(self.h_sequence)
 
-    def get_outputs_hash(self) -> bytes:
+    def get_outputs_hash(self, coin: CoinInfo) -> bytes:
         return get_tx_hash(self.h_outputs)
 
     def preimage_hash(
@@ -103,11 +92,17 @@ class Zip143:
         )  # 1. nVersion | fOverwintered
         write_uint32(h_preimage, tx.version_group_id)  # 2. nVersionGroupId
         # 3. hashPrevouts
-        write_bytes_fixed(h_preimage, bytearray(self.get_prevouts_hash()), TX_HASH_SIZE)
+        write_bytes_fixed(
+            h_preimage, bytearray(self.get_prevouts_hash(coin)), TX_HASH_SIZE
+        )
         # 4. hashSequence
-        write_bytes_fixed(h_preimage, bytearray(self.get_sequence_hash()), TX_HASH_SIZE)
+        write_bytes_fixed(
+            h_preimage, bytearray(self.get_sequence_hash(coin)), TX_HASH_SIZE
+        )
         # 5. hashOutputs
-        write_bytes_fixed(h_preimage, bytearray(self.get_outputs_hash()), TX_HASH_SIZE)
+        write_bytes_fixed(
+            h_preimage, bytearray(self.get_outputs_hash(coin)), TX_HASH_SIZE
+        )
         # 6. hashJoinSplits
         write_bytes_fixed(h_preimage, b"\x00" * TX_HASH_SIZE, TX_HASH_SIZE)
         write_uint32(h_preimage, tx.lock_time)  # 7. nLockTime
@@ -153,11 +148,17 @@ class Zip243(Zip143):
         )  # 1. nVersion | fOverwintered
         write_uint32(h_preimage, tx.version_group_id)  # 2. nVersionGroupId
         # 3. hashPrevouts
-        write_bytes_fixed(h_preimage, bytearray(self.get_prevouts_hash()), TX_HASH_SIZE)
+        write_bytes_fixed(
+            h_preimage, bytearray(self.get_prevouts_hash(coin)), TX_HASH_SIZE
+        )
         # 4. hashSequence
-        write_bytes_fixed(h_preimage, bytearray(self.get_sequence_hash()), TX_HASH_SIZE)
+        write_bytes_fixed(
+            h_preimage, bytearray(self.get_sequence_hash(coin)), TX_HASH_SIZE
+        )
         # 5. hashOutputs
-        write_bytes_fixed(h_preimage, bytearray(self.get_outputs_hash()), TX_HASH_SIZE)
+        write_bytes_fixed(
+            h_preimage, bytearray(self.get_outputs_hash(coin)), TX_HASH_SIZE
+        )
 
         zero_hash = b"\x00" * TX_HASH_SIZE
         write_bytes_fixed(h_preimage, zero_hash, TX_HASH_SIZE)  # 6. hashJoinSplits