[LAB8] 313552024

lab8/solve.py

@@ -1,10 +1,34 @@
 #!/usr/bin/env python3
 
 import angr,sys
+import claripy
 
 def main():
-    secret_key = b""
-    sys.stdout.buffer.write(secret_key)
+    # 載入二進位檔並關閉自動載入庫功能
+    proj = angr.Project('./chal', auto_load_libs=False)
+
+    # 建立 8 個符號位元組 (symbolic bytes)
+    sym_bytes = [claripy.BVS(f'byte_{i}', 8) for i in range(8)]
+    sym_input = claripy.Concat(*sym_bytes)
+
+    # 使用符號 stdin 初始化模擬狀態
+    state = proj.factory.full_init_state(
+        stdin=angr.SimFileStream(name='stdin', content=sym_input, has_end=True)
+    )
+
+    # 探索至輸出包含 "Correct!" 的執行路徑
+    simgr = proj.factory.simgr(state)
+    simgr.explore(find=lambda s: b"Correct!" in s.posix.dumps(1))
+
+    if simgr.found:
+        found = simgr.found[0]
+        secret_key = found.solver.eval(sym_input, cast_to=bytes)
+        sys.stdout.buffer.write(secret_key)
+    else:
+        print("No solution found")
+
+    # secret_key = b""
+    # sys.stdout.buffer.write(secret_key)
 
 
 if __name__ == '__main__':