From b099a24861150f9b33891f4b8c182d5295eb9ed4 Mon Sep 17 00:00:00 2001
From: Bernhard Mueller <bernhard.mueller11@gmail.com>
Date: Mon, 24 Feb 2020 10:06:12 +0700
Subject: [PATCH] Add flashfck module

---
 mythril/analysis/module/modules/flashfck.py | 77 +++++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 mythril/analysis/module/modules/flashfck.py

diff --git a/mythril/analysis/module/modules/flashfck.py b/mythril/analysis/module/modules/flashfck.py
new file mode 100644
index 00000000..379a1501
--- /dev/null
+++ b/mythril/analysis/module/modules/flashfck.py
@@ -0,0 +1,77 @@
+"""This module contains the detection code for arbitrary storage write."""
+import logging
+from mythril.analysis.modules.base import DetectionModule
+
+from mythril.analysis.report import Issue
+
+from mythril.analysis.swc_data import WRITE_TO_ARBITRARY_STORAGE
+from mythril.laser.ethereum.state.global_state import GlobalState
+from mythril.laser.smt import symbol_factory
+
+log = logging.getLogger(__name__)
+
+DESCRIPTION = """
+
+Search for arbitrage opportunities with large capital
+"""
+
+
+class FlashFck(DetectionModule):
+    """This module searches for flash loan arbitrage opportunities."""
+
+    def __init__(self):
+        """"""
+        super().__init__(
+            name="Flash Loan Attack",
+            swc_id=0,
+            description=DESCRIPTION,
+            entrypoint="post",
+        )
+
+    def reset_module(self):
+        """
+        Resets the module by clearing everything
+        :return:
+        """
+        super().reset_module()
+
+    def _execute(self, state: GlobalState) -> None:
+        """
+
+        :param state:
+        :return:
+        """
+        if state.get_current_instruction()["address"] in self.cache:
+            return
+        issues = self._analyze_state(state)
+
+
+    def _analyze_state(self, state):
+        """
+
+        :param state:
+        :return:
+        """
+
+        write_slot = state.mstate.stack[-1]
+        constraints = state.world_state.constraints + [
+            write_slot == symbol_factory.BitVecVal(324345425435, 256)
+        ]
+
+        issue = Issue(
+            contract=state.environment.active_account.contract_name,
+            function_name=state.environment.active_function_name,
+            address=state.get_current_instruction()["address"],
+            swc_id=WRITE_TO_ARBITRARY_STORAGE,
+            title="Write to an arbitrary storage slot",
+            severity="High",
+            bytecode=state.environment.code.bytecode,
+            description_head="Any storage slot can be written by the caller.",
+            description_tail="The attacker can modify any value in the storage."
+            + " This can lead to unintended consequences.",
+            detector=self,
+        )
+        return [issue]
+
+
+detector = FlashFck()