core: allow spending coins from Bitcoin paths if the coin ...

has implemented strong replay protection via SIGHASH_FORKID
trezor · Aug 16, 2020 · 6def758 · 6def758
1 parent f6be9eb
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diff --git a/core/CHANGELOG.md b/core/CHANGELOG.md
@@ -14,6 +14,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Changed
 - Print inverted question mark for non-printable characters.
 - Remove pre-fill bar from text rendering functions.  [#1173]
+- Allow spending coins from Bitcoin paths if the coin has implemented strong replay protection via `SIGHASH_FORKID`.  [#1188]
 
 ### Deprecated
 
@@ -264,3 +265,4 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 [#1139]: https://github.com/trezor/trezor-firmware/issues/1139
 [#1165]: https://github.com/trezor/trezor-firmware/pull/1165
 [#1173]: https://github.com/trezor/trezor-firmware/pull/1173
+[#1188]: https://github.com/trezor/trezor-firmware/issues/1188
diff --git a/core/src/apps/bitcoin/keychain.py b/core/src/apps/bitcoin/keychain.py
@@ -56,6 +56,16 @@ def get_namespaces_for_coin(coin: coininfo.CoinInfo):
         # m/0x4741b11e/6/pointer
         namespaces.append([0x4741B11E])
 
+    # some wallets such as Electron-Cash (BCH) store coins on Bitcoin paths
+    # we can allow spending these coins from Bitcoin paths if the coin has
+    # implemented strong replay protection via SIGHASH_FORKID
+    if coin.fork_id is not None:
+        namespaces.append([44 | HARDENED, 0 | HARDENED])
+        namespaces.append([48 | HARDENED, 0 | HARDENED])
+        if coin.segwit:
+            namespaces.append([49 | HARDENED, 0 | HARDENED])
+            namespaces.append([84 | HARDENED, 0 | HARDENED])
+
     return namespaces
 
 

diff --git a/core/tests/test_apps.wallet.keychain.py b/core/tests/test_apps.wallet.keychain.py
@@ -87,14 +87,46 @@ def test_bcash(self):
         self.assertFalse(coin.segwit)
         valid_addresses = (
             [44 | HARDENED, 145 | HARDENED],
+            [44 | HARDENED, 0 | HARDENED],
             [45 | HARDENED, 123456],
             [48 | HARDENED, 145 | HARDENED],
+            [48 | HARDENED, 0 | HARDENED],
         )
         invalid_addresses = (
             [43 | HARDENED, 145 | HARDENED],
-            [44 | HARDENED, 0 | HARDENED],
+            [43 | HARDENED, 0 | HARDENED],
             [49 | HARDENED, 145 | HARDENED],
+            [49 | HARDENED, 0 | HARDENED],
             [84 | HARDENED, 145 | HARDENED],
+            [84 | HARDENED, 0 | HARDENED],
+        )
+
+        for addr in valid_addresses:
+            keychain.derive(addr)
+
+        for addr in invalid_addresses:
+            self.assertRaises(wire.DataError, keychain.derive, addr)
+
+    def test_litecoin(self):
+        keychain, coin = await_result(
+            get_keychain_for_coin(wire.DUMMY_CONTEXT, "Litecoin")
+        )
+        self.assertEqual(coin.coin_name, "Litecoin")
+
+        self.assertTrue(coin.segwit)
+        valid_addresses = (
+            [44 | HARDENED, 2 | HARDENED],
+            [45 | HARDENED, 123456],
+            [48 | HARDENED, 2 | HARDENED],
+            [49 | HARDENED, 2 | HARDENED],
+            [84 | HARDENED, 2 | HARDENED],
+        )
+        invalid_addresses = (
+            [43 | HARDENED, 2 | HARDENED],
+            [44 | HARDENED, 0 | HARDENED],
+            [48 | HARDENED, 0 | HARDENED],
+            [49 | HARDENED, 0 | HARDENED],
+            [84 | HARDENED, 0 | HARDENED],
         )
 
         for addr in valid_addresses: