EELS Update: Update EIP-6110 (#1143)

* check log topic for deposit requests

* check deposit log validity

* use Uint for parsing deposit logs

Author: gurukamath

src/ethereum/prague/requests.py

@@ -12,29 +12,138 @@
 from typing import List, Union
 
 from ethereum_types.bytes import Bytes
+from ethereum_types.numeric import Uint, ulen
+
+from ethereum.exceptions import InvalidBlock
+from ethereum.utils.hexadecimal import hex_to_bytes32
 
 from .blocks import Receipt, decode_receipt
 from .utils.hexadecimal import hex_to_address
 
 DEPOSIT_CONTRACT_ADDRESS = hex_to_address(
     "0x00000000219ab540356cbb839cbe05303d7705fa"
 )
+DEPOSIT_EVENT_SIGNATURE_HASH = hex_to_bytes32(
+    "0x649bbc62d0e31342afea4e5cd82d4049e7e1ee912fc0889aa790803be39038c5"
+)
 DEPOSIT_REQUEST_TYPE = b"\x00"
 WITHDRAWAL_REQUEST_TYPE = b"\x01"
 CONSOLIDATION_REQUEST_TYPE = b"\x02"
 
 
+DEPOSIT_EVENT_LENGTH = Uint(576)
+
+PUBKEY_OFFSET = Uint(160)
+WITHDRAWAL_CREDENTIALS_OFFSET = Uint(256)
+AMOUNT_OFFSET = Uint(320)
+SIGNATURE_OFFSET = Uint(384)
+INDEX_OFFSET = Uint(512)
+
+PUBKEY_SIZE = Uint(48)
+WITHDRAWAL_CREDENTIALS_SIZE = Uint(32)
+AMOUNT_SIZE = Uint(8)
+SIGNATURE_SIZE = Uint(96)
+INDEX_SIZE = Uint(8)
+
+
 def extract_deposit_data(data: Bytes) -> Bytes:
     """
     Extracts Deposit Request from the DepositContract.DepositEvent data.
+
+    Raises
+    ------
+    InvalidBlock :
+        If the deposit contract did not produce a valid log.
     """
-    return (
-        data[192:240]  # public_key
-        + data[288:320]  # withdrawal_credentials
-        + data[352:360]  # amount
-        + data[416:512]  # signature
-        + data[544:552]  # index
+    if ulen(data) != DEPOSIT_EVENT_LENGTH:
+        raise InvalidBlock("Invalid deposit event data length")
+
+    # Check that all the offsets are in order
+    pubkey_offset = Uint.from_be_bytes(data[0:32])
+    if pubkey_offset != PUBKEY_OFFSET:
+        raise InvalidBlock("Invalid pubkey offset in deposit log")
+
+    withdrawal_credentials_offset = Uint.from_be_bytes(data[32:64])
+    if withdrawal_credentials_offset != WITHDRAWAL_CREDENTIALS_OFFSET:
+        raise InvalidBlock(
+            "Invalid withdrawal credentials offset in deposit log"
+        )
+
+    amount_offset = Uint.from_be_bytes(data[64:96])
+    if amount_offset != AMOUNT_OFFSET:
+        raise InvalidBlock("Invalid amount offset in deposit log")
+
+    signature_offset = Uint.from_be_bytes(data[96:128])
+    if signature_offset != SIGNATURE_OFFSET:
+        raise InvalidBlock("Invalid signature offset in deposit log")
+
+    index_offset = Uint.from_be_bytes(data[128:160])
+    if index_offset != INDEX_OFFSET:
+        raise InvalidBlock("Invalid index offset in deposit log")
+
+    # Check that all the sizes are in order
+    pubkey_size = Uint.from_be_bytes(
+        data[pubkey_offset : pubkey_offset + Uint(32)]
     )
+    if pubkey_size != PUBKEY_SIZE:
+        raise InvalidBlock("Invalid pubkey size in deposit log")
+
+    pubkey = data[
+        pubkey_offset + Uint(32) : pubkey_offset + Uint(32) + PUBKEY_SIZE
+    ]
+
+    withdrawal_credentials_size = Uint.from_be_bytes(
+        data[
+            withdrawal_credentials_offset : withdrawal_credentials_offset
+            + Uint(32)
+        ],
+    )
+    if withdrawal_credentials_size != WITHDRAWAL_CREDENTIALS_SIZE:
+        raise InvalidBlock(
+            "Invalid withdrawal credentials size in deposit log"
+        )
+
+    withdrawal_credentials = data[
+        withdrawal_credentials_offset
+        + Uint(32) : withdrawal_credentials_offset
+        + Uint(32)
+        + WITHDRAWAL_CREDENTIALS_SIZE
+    ]
+
+    amount_size = Uint.from_be_bytes(
+        data[amount_offset : amount_offset + Uint(32)]
+    )
+    if amount_size != AMOUNT_SIZE:
+        raise InvalidBlock("Invalid amount size in deposit log")
+
+    amount = data[
+        amount_offset + Uint(32) : amount_offset + Uint(32) + AMOUNT_SIZE
+    ]
+
+    signature_size = Uint.from_be_bytes(
+        data[signature_offset : signature_offset + Uint(32)]
+    )
+    if signature_size != SIGNATURE_SIZE:
+        raise InvalidBlock("Invalid signature size in deposit log")
+
+    signature = data[
+        signature_offset
+        + Uint(32) : signature_offset
+        + Uint(32)
+        + SIGNATURE_SIZE
+    ]
+
+    index_size = Uint.from_be_bytes(
+        data[index_offset : index_offset + Uint(32)]
+    )
+    if index_size != INDEX_SIZE:
+        raise InvalidBlock("Invalid index size in deposit log")
+
+    index = data[
+        index_offset + Uint(32) : index_offset + Uint(32) + INDEX_SIZE
+    ]
+
+    return pubkey + withdrawal_credentials + amount + signature + index
 
 
 def parse_deposit_requests_from_receipt(
@@ -47,8 +156,12 @@ def parse_deposit_requests_from_receipt(
     decoded_receipt = decode_receipt(receipt)
     for log in decoded_receipt.logs:
         if log.address == DEPOSIT_CONTRACT_ADDRESS:
-            request = extract_deposit_data(log.data)
-            deposit_requests += request
+            if (
+                len(log.topics) > 0
+                and log.topics[0] == DEPOSIT_EVENT_SIGNATURE_HASH
+            ):
+                request = extract_deposit_data(log.data)
+                deposit_requests += request
 
     return deposit_requests