feat: use passphrase for validator registration/update (#184)

Author: shahin-hq

crypto/identity/proof_of_possession.py

@@ -0,0 +1,53 @@
+import sys
+import os
+from os.path import dirname
+
+sys.path.append(os.path.join(dirname(dirname(__file__)), 'thirdparty/bls-signatures/python-impl'))
+
+from schemes import PopSchemeMPL, PrivateKey as BLSSchemePrivateKey
+
+from crypto.identity.bls_private_key import BLSPrivateKey
+
+
+class ProofOfPossession:
+    @staticmethod
+    def derive_bls_private_key(passphrase: str) -> bytes:
+        """Derives a BLS private key (32 bytes) from a BIP-39 mnemonic."""
+        return BLSPrivateKey.from_passphrase(passphrase).private_key
+
+    @classmethod
+    def derive_bls_public_key(cls, passphrase: str) -> str:
+        """Derives the BLS12-381 G1 public key from a mnemonic. Returns hex (96 chars)."""
+        sk = BLSSchemePrivateKey.from_bytes(cls.derive_bls_private_key(passphrase))
+        return bytes(sk.get_g1()).hex()
+
+    @classmethod
+    def build_proof_of_possession(cls, private_key_bytes: bytes) -> dict:
+        """Builds proof of possession for a given private key.
+
+        Args:
+            private_key_bytes: 32-byte BLS private key
+
+        Returns:
+            dict with 'pk' (hex, 48 bytes G1) and 'pop' (hex, 96 bytes G2)
+
+        Raises:
+            ValueError: if the key is not exactly 32 bytes or is the zero scalar
+        """
+        if int.from_bytes(private_key_bytes, 'big') == 0:
+            raise ValueError('BLS secret key must not be zero')
+
+        sk  = BLSSchemePrivateKey.from_bytes(private_key_bytes)
+        pk  = bytes(sk.get_g1()).hex()
+        pop = bytes(PopSchemeMPL.pop_prove(sk)).hex()
+
+        return {'pk': pk, 'pop': pop}
+
+    @classmethod
+    def from_passphrase(cls, passphrase: str) -> dict:
+        """Convenience: derives private key from mnemonic and builds PoP.
+
+        Returns:
+            dict with 'pk' (hex, 48 bytes G1) and 'pop' (hex, 96 bytes G2)
+        """
+        return cls.build_proof_of_possession(cls.derive_bls_private_key(passphrase))

crypto/transactions/builder/validator_registration_builder.py

@@ -1,15 +1,18 @@
 from crypto.enums.contract_addresses import ContractAddresses
+from crypto.identity.proof_of_possession import ProofOfPossession
 from crypto.transactions.builder.abstract_transaction_builder import AbstractTransactionBuilder
 from crypto.transactions.types.validator_registration import ValidatorRegistration
 
+
 class ValidatorRegistrationBuilder(AbstractTransactionBuilder):
     def __init__(self, data: dict):
         super().__init__(data)
-
         self.to(ContractAddresses.CONSENSUS.value)
 
-    def validator_public_key(self, validator_public_key: str):
-        self.transaction.data['validatorPublicKey'] = validator_public_key
+    def validator_passphrase(self, passphrase: str):
+        bls = ProofOfPossession.from_passphrase(passphrase)
+        self.transaction.data['validatorPublicKey'] = '0x' + bls['pk']
+        self.transaction.data['validatorProof']     = '0x' + bls['pop']
         self.transaction.refresh_payload_data()
         return self
 

crypto/transactions/builder/validator_update_builder.py

@@ -0,0 +1,20 @@
+from crypto.enums.contract_addresses import ContractAddresses
+from crypto.identity.proof_of_possession import ProofOfPossession
+from crypto.transactions.builder.abstract_transaction_builder import AbstractTransactionBuilder
+from crypto.transactions.types.validator_update import ValidatorUpdate
+
+
+class ValidatorUpdateBuilder(AbstractTransactionBuilder):
+    def __init__(self, data: dict):
+        super().__init__(data)
+        self.to(ContractAddresses.CONSENSUS.value)
+
+    def validator_passphrase(self, passphrase: str):
+        bls = ProofOfPossession.from_passphrase(passphrase)
+        self.transaction.data['validatorPublicKey'] = '0x' + bls['pk']
+        self.transaction.data['validatorProof']     = '0x' + bls['pop']
+        self.transaction.refresh_payload_data()
+        return self
+
+    def get_transaction_instance(self, data: dict):
+        return ValidatorUpdate(data)

crypto/transactions/deserializer.py

@@ -12,6 +12,7 @@
 from crypto.transactions.types.unvote import Unvote
 from crypto.transactions.types.validator_registration import ValidatorRegistration
 from crypto.transactions.types.validator_resignation import ValidatorResignation
+from crypto.transactions.types.validator_update import ValidatorUpdate
 
 from crypto.enums.abi_function import AbiFunction
 from crypto.utils.abi_decoder import AbiDecoder
@@ -95,6 +96,9 @@ def __guess_transaction_from_data(self, data: dict) -> AbstractTransaction:
             if function_name == AbiFunction.VALIDATOR_RESIGNATION.value:
                 return ValidatorResignation(data)
 
+            if function_name == AbiFunction.UPDATE_VALIDATOR.value:
+                return ValidatorUpdate(data)
+
         username_payload_data = self.decode_payload(data, ContractAbiType.USERNAMES)
         if username_payload_data is not None:
             function_name = username_payload_data.get('functionName')

crypto/transactions/types/validator_registration.py

@@ -1,19 +1,21 @@
-from typing import Optional
 from crypto.transactions.types.abstract_transaction import AbstractTransaction
 from crypto.utils.abi_encoder import AbiEncoder
 from crypto.enums.abi_function import AbiFunction
-from crypto.utils.transaction_utils import TransactionUtils
+
 
 class ValidatorRegistration(AbstractTransaction):
     def __init__(self, data: dict):
         payload = self._decode_payload(data)
         if payload:
-            data['validatorPublicKey'] = TransactionUtils.parse_hex_from_str(payload.get('args', [None])[0]) if payload.get('args') else None
+            data['validatorPublicKey'], data['validatorProof'] = payload['args']
 
         super().__init__(data)
 
     def get_payload(self) -> str:
-        if 'validatorPublicKey' not in self.data:
+        if 'validatorPublicKey' not in self.data or 'validatorProof' not in self.data:
             return ''
         encoder = AbiEncoder()
-        return encoder.encode_function_call(AbiFunction.VALIDATOR_REGISTRATION.value, ['0x' + self.data['validatorPublicKey']])
+        return encoder.encode_function_call(
+            AbiFunction.VALIDATOR_REGISTRATION.value,
+            [self.data['validatorPublicKey'], self.data['validatorProof']],
+        )

crypto/transactions/types/validator_update.py

@@ -0,0 +1,21 @@
+from crypto.transactions.types.abstract_transaction import AbstractTransaction
+from crypto.utils.abi_encoder import AbiEncoder
+from crypto.enums.abi_function import AbiFunction
+
+
+class ValidatorUpdate(AbstractTransaction):
+    def __init__(self, data: dict):
+        payload = self._decode_payload(data)
+        if payload:
+            data['validatorPublicKey'], data['validatorProof'] = payload['args']
+
+        super().__init__(data)
+
+    def get_payload(self) -> str:
+        if 'validatorPublicKey' not in self.data or 'validatorProof' not in self.data:
+            return ''
+        encoder = AbiEncoder()
+        return encoder.encode_function_call(
+            AbiFunction.UPDATE_VALIDATOR.value,
+            [self.data['validatorPublicKey'], self.data['validatorProof']],
+        )