apps: move ed25519 prefix common function

src/apps/common/seed.py

@@ -45,6 +45,6 @@ def derive_node_without_passphrase(
     return node
 
 
-def remove_ed25519_public_key_prefix(pubkey: bytes) -> bytes:
+def remove_ed25519_prefix(pubkey: bytes) -> bytes:
     # 0x01 prefix is not part of the actual public key, hence removed
     return pubkey[1:]

src/apps/nem/signing.py

@@ -18,7 +18,7 @@ async def sign_tx(ctx, msg: NEMSignTx):
         await multisig.ask(ctx, msg)
         common = msg.multisig
     else:
-        public_key = _get_public_key(node)
+        public_key = seed.remove_ed25519_prefix(node.public_key())
         common = msg.transaction
 
     if msg.transfer:
@@ -48,10 +48,15 @@ async def sign_tx(ctx, msg: NEMSignTx):
         # wrap transaction in multisig wrapper
         if msg.cosigning:
             tx = multisig.cosign(
-                _get_public_key(node), msg.transaction, tx, msg.multisig.signer
+                seed.remove_ed25519_prefix(node.public_key()),
+                msg.transaction,
+                tx,
+                msg.multisig.signer,
             )
         else:
-            tx = multisig.initiate(_get_public_key(node), msg.transaction, tx)
+            tx = multisig.initiate(
+                seed.remove_ed25519_prefix(node.public_key()), msg.transaction, tx
+            )
 
     signature = ed25519.sign(node.private_key(), tx, NEM_HASH_ALG)
 
@@ -59,8 +64,3 @@ async def sign_tx(ctx, msg: NEMSignTx):
     resp.data = tx
     resp.signature = signature
     return resp
-
-
-def _get_public_key(node) -> bytes:
-    # 0x01 prefix is not part of the actual public key, hence removed
-    return node.public_key()[1:]

src/apps/stellar/get_address.py

@@ -7,7 +7,7 @@ from trezor.messages.StellarGetAddress import StellarGetAddress
 
 async def get_address(ctx, msg: StellarGetAddress):
     node = await seed.derive_node(ctx, msg.address_n, helpers.STELLAR_CURVE)
-    pubkey = seed.remove_ed25519_public_key_prefix(node.public_key())  # todo better?
+    pubkey = seed.remove_ed25519_prefix(node.public_key())
     address = helpers.address_from_public_key(pubkey)
 
     if msg.show_display:

src/apps/stellar/get_public_key.py

@@ -12,7 +12,7 @@ from ubinascii import hexlify
 
 async def get_public_key(ctx, msg: StellarGetPublicKey):
     node = await seed.derive_node(ctx, msg.address_n, helpers.STELLAR_CURVE)
-    pubkey = seed.remove_ed25519_public_key_prefix(node.public_key())  # todo better?
+    pubkey = seed.remove_ed25519_prefix(node.public_key())
 
     if msg.show_display:
         while True:

src/apps/stellar/sign_tx.py

@@ -18,7 +18,7 @@ async def sign_tx(ctx, msg: StellarSignTx):
         raise ValueError('Stellar: At least one operation is required')
 
     node = await seed.derive_node(ctx, msg.address_n, consts.STELLAR_CURVE)
-    pubkey = seed.remove_ed25519_public_key_prefix(node.public_key())
+    pubkey = seed.remove_ed25519_prefix(node.public_key())
 
     w = bytearray()
     await _init(ctx, w, pubkey, msg)