core/cardano: use caching decorators and new Keychain API for Cardano as well

core/src/apps/cardano/get_address.py

@@ -7,9 +7,8 @@ from apps.common import paths
 from apps.common.layout import address_n_to_str, show_address, show_qr
 
 
-async def get_address(ctx, msg):
+@seed.with_keychain
-    keychain = await seed.get_keychain(ctx)
+async def get_address(ctx, msg, keychain: seed.Keychain):
-
     await paths.validate_path(ctx, validate_full_path, keychain, msg.address_n, CURVE)
 
     try:

core/src/apps/cardano/get_public_key.py

@@ -10,9 +10,8 @@ from apps.common import layout, paths
 from apps.common.seed import remove_ed25519_prefix
 
 
-async def get_public_key(ctx, msg):
+@seed.with_keychain
-    keychain = await seed.get_keychain(ctx)
+async def get_public_key(ctx, msg, keychain: seed.Keychain):
-
     await paths.validate_path(
         ctx,
         paths.validate_path_for_get_public_key,

core/src/apps/cardano/seed.py

@@ -3,54 +3,64 @@ from storage import cache
 from trezor import wire
 from trezor.crypto import bip32
 
-from apps.cardano import CURVE, SEED_NAMESPACE
+from apps.cardano import SEED_NAMESPACE
 from apps.common import mnemonic
 from apps.common.passphrase import get as get_passphrase
 
+if False:
+    from typing import Tuple
+
+    from apps.common.seed import Bip32Path, MsgIn, MsgOut, Handler, HandlerWithKeychain
+
 
 class Keychain:
-    def __init__(self, path: list, root: bip32.HDNode):
+    """Cardano keychain hard-coded to SEED_NAMESPACE."""
-        self.path = path
+
+    def __init__(self, root: bip32.HDNode) -> None:
         self.root = root
 
-    def validate_path(self, checked_path: list, checked_curve: str):
+    def match_path(self, path: Bip32Path) -> Tuple[int, Bip32Path]:
-        if checked_curve != CURVE or checked_path[:2] != SEED_NAMESPACE:
+        if path[: len(SEED_NAMESPACE)] != SEED_NAMESPACE:
             raise wire.DataError("Forbidden key path")
+        return 0, path[len(SEED_NAMESPACE) :]
 
-    def derive(self, node_path: list) -> bip32.HDNode:
+    def derive(self, node_path: Bip32Path) -> bip32.HDNode:
-        # check we are in the cardano namespace
+        _, suffix = self.match_path(node_path)
-        prefix = node_path[: len(self.path)]
-        suffix = node_path[len(self.path) :]
-        if prefix != self.path:
-            raise wire.DataError("Forbidden key path")
         # derive child node from the root
         node = self.root.clone()
         for i in suffix:
             node.derive_cardano(i)
         return node
 
+    # XXX the root node remains in session cache so we should not delete it
+    # def __del__(self) -> None:
+    #     self.root.__del__()
 
+
+@cache.stored_async(cache.APP_CARDANO_ROOT)
 async def get_keychain(ctx: wire.Context) -> Keychain:
-    root = cache.get(cache.APP_CARDANO_ROOT)
-
     if not storage.is_initialized():
         raise wire.NotInitialized("Device is not initialized")
 
-    if root is None:
+    passphrase = await get_passphrase(ctx)
-        passphrase = await get_passphrase(ctx)
+    if mnemonic.is_bip39():
-        if mnemonic.is_bip39():
+        # derive the root node from mnemonic and passphrase
-            # derive the root node from mnemonic and passphrase
+        root = bip32.from_mnemonic_cardano(mnemonic.get_secret().decode(), passphrase)
-            root = bip32.from_mnemonic_cardano(
+    else:
-                mnemonic.get_secret().decode(), passphrase
+        seed = mnemonic.get_seed(passphrase)
-            )
+        root = bip32.from_seed(seed, "ed25519 cardano seed")
-        else:
-            seed = mnemonic.get_seed(passphrase)
-            root = bip32.from_seed(seed, "ed25519 cardano seed")
 
-        # derive the namespaced root node
+    # derive the namespaced root node
-        for i in SEED_NAMESPACE:
+    for i in SEED_NAMESPACE:
-            root.derive_cardano(i)
+        root.derive_cardano(i)
-        storage.cache.set(cache.APP_CARDANO_ROOT, root)
 
-    keychain = Keychain(SEED_NAMESPACE, root)
+    keychain = Keychain(root)
     return keychain
+
+
+def with_keychain(func: HandlerWithKeychain[MsgIn, MsgOut]) -> Handler[MsgIn, MsgOut]:
+    async def wrapper(ctx: wire.Context, msg: MsgIn) -> MsgOut:
+        keychain = await get_keychain(ctx)
+        return await func(ctx, msg, keychain)
+
+    return wrapper

core/src/apps/cardano/sign_tx.py

@@ -63,9 +63,8 @@ async def request_transaction(ctx, tx_req: CardanoTxRequest, index: int):
     return await ctx.call(tx_req, CardanoTxAck)
 
 
-async def sign_tx(ctx, msg):
+@seed.with_keychain
-    keychain = await seed.get_keychain(ctx)
+async def sign_tx(ctx, msg, keychain: seed.Keychain):
-
     progress.init(msg.transactions_count, "Loading data")
 
     try:

core/tests/test_apps.cardano.address.py

@@ -21,7 +21,7 @@ class TestCardanoAddress(unittest.TestCase):
         node = bip32.from_mnemonic_cardano(mnemonic, passphrase)
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         addresses = [
             "Ae2tdPwUPEZ98eHFwxSsPBDz73amioKpr58Vw85mP1tMkzq8siaftiejJ3j",
@@ -68,7 +68,7 @@ class TestCardanoAddress(unittest.TestCase):
         node = bip32.from_mnemonic_cardano(mnemonic, passphrase)
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         addresses = [
             "Ae2tdPwUPEZ5YUb8sM3eS8JqKgrRLzhiu71crfuH2MFtqaYr5ACNRdsswsZ",
@@ -116,7 +116,7 @@ class TestCardanoAddress(unittest.TestCase):
         node = bip32.from_mnemonic_cardano(mnemonic, passphrase)
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         # 44'/1815'
         address, _ = derive_address_and_node(keychain, [0x80000000 | 44, 0x80000000 | 1815])
@@ -207,7 +207,7 @@ class TestCardanoAddress(unittest.TestCase):
         # Check derived nodes and addresses.
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         nodes = [
             (
@@ -271,7 +271,7 @@ class TestCardanoAddress(unittest.TestCase):
         # Check derived nodes and addresses.
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         nodes = [
             (

core/tests/test_apps.cardano.get_public_key.py

@@ -13,7 +13,7 @@ class TestCardanoGetPublicKey(unittest.TestCase):
         node = bip32.from_mnemonic_cardano(mnemonic, passphrase)
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         derivation_paths = [
             [0x80000000 | 44, 0x80000000 | 1815, 0x80000000, 0, 0x80000000],
@@ -67,7 +67,7 @@ class TestCardanoGetPublicKey(unittest.TestCase):
 
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         # 44'/1815'/0'/0/i
         derivation_paths = [
@@ -118,7 +118,7 @@ class TestCardanoGetPublicKey(unittest.TestCase):
 
         node.derive_cardano(0x80000000 | 44)
         node.derive_cardano(0x80000000 | 1815)
-        keychain = Keychain([0x80000000 | 44, 0x80000000 | 1815], node)
+        keychain = Keychain(node)
 
         # 44'/1815'/0'/0/i
         derivation_paths = [