xmr: sign cleanup, comments

- state cleanup, comments added, unused code removed

src/apps/monero/protocol/signing/state.py

@@ -54,17 +54,15 @@ def __init__(self, ctx):
         self.tx_priv = None
         self.tx_pub = None
 
-        self.multi_sig = False
         self.need_additional_txkeys = False
         self.use_bulletproof = False
-        self.use_rct = True
         self.use_simple_rct = False
         self.input_count = 0
         self.output_count = 0
         self.output_change = None
         self.mixin = 0
         self.fee = 0
-        self.account_idx = 0
+        self.account_idx = 0  # wallet sub-address major index
 
         self.additional_tx_private_keys = []
         self.additional_tx_public_keys = []
@@ -73,8 +71,6 @@ def __init__(self, ctx):
         self.summary_inputs_money = 0
         self.summary_outs_money = 0
         self.input_secrets = []
-        self.input_alphas = []
-        self.input_pseudo_outs = []
         self.output_sk_masks = []
         self.output_pk_masks = []  # commitments
         self.output_amounts = []
@@ -90,8 +86,7 @@ def __init__(self, ctx):
         self.tx_prefix_hasher = None
         self.tx_prefix_hash = None
         self.full_message_hasher = None
-        self.full_message = None
-        self.exp_tx_prefix_hash = None
+        self.full_message = None  # pre-MLSAG hash
         self._init()
 
     def _init(self):

src/apps/monero/protocol/signing/step_01_init_transaction.py

@@ -38,8 +38,8 @@ async def init_transaction(
     state.mixin = tsx_data.mixin
     state.fee = tsx_data.fee
     state.account_idx = tsx_data.account
-    state.multi_sig = tsx_data.is_multisig
-    state.exp_tx_prefix_hash = tsx_data.exp_tx_prefix_hash
+    if tsx_data.is_multisig:
+        raise NotImplementedError("Multisig is not implemented")
 
     # Ensure change is correct
     _check_change(state, tsx_data.outputs)

src/apps/monero/protocol/signing/step_03_inputs_permutation.py

@@ -27,7 +27,7 @@ async def tsx_inputs_permutation(state: State, permutation: list):
     Set permutation on the inputs - sorted by key image on host.
     """
     if len(permutation) != state.input_count:
-        raise ValueError('Invalid permutation size')
+        raise ValueError("Invalid permutation size")
     _check_permutation(permutation)
 
     state.source_permutation = permutation

src/apps/monero/protocol/signing/step_05_all_in_set.py

@@ -29,7 +29,8 @@ async def all_in_set(state: State, rsig_data):  # todo: rsig_data not used?
     if not state.rsig_offload:
         return resp
 
-    # Simple offloading - generate random masks that sum to the input mask sum.
+    # Simple range proof offloading
+    # Generate random commitment masks that sum to the input mask sum.
     tmp_buff = bytearray(32)
     rsig_data.mask = bytearray(32 * state.output_count)
     state.sumout = crypto.sc_init(0)

src/apps/monero/protocol/signing/step_07_all_out1_set.py

@@ -8,9 +8,8 @@
 
 from .state import State
 
-from apps.monero.controller import misc
 from apps.monero.layout import confirms
-from apps.monero.xmr import common, crypto
+from apps.monero.xmr import crypto
 
 
 async def all_out1_set(state: State):

src/apps/monero/protocol/signing/step_08_mlsag_done.py

@@ -15,7 +15,6 @@ async def mlsag_done(state: State):
     # state.state.set_final_message_done()  todo needed?
     await confirms.transaction_step(state.ctx, state.STEP_MLSAG)
 
-    _ecdh_info(state)
     _out_pk(state)
     state.full_message_hasher.rctsig_base_done()
     state.current_output_index = -1
@@ -27,13 +26,6 @@ async def mlsag_done(state: State):
     return MoneroTransactionMlsagDoneAck(full_message_hash=state.full_message)
 
 
-def _ecdh_info(state: State):  # todo why is it here? remove
-    """
-    Sets ecdh info for the incremental hashing mlsag.
-    """
-    pass
-
-
 def _out_pk(state: State):
     """
     Sets out_pk for the incremental hashing mlsag.