Merge pull request #563 from Ramez96/lab8

[LAB8] 313553801

Author: YingMuo

lab8/solve.py

@@ -1,11 +1,41 @@
 #!/usr/bin/env python3
 
-import angr,sys
+import angr
+import claripy
+import sys
 
 def main():
-    secret_key = b""
-    sys.stdout.buffer.write(secret_key)
+    # Define the input length and create symbolic variables
+    input_len = 8
+    chars = [claripy.BVS(f'char_{i}', 8) for i in range(input_len)]
+    sym_input = claripy.Concat(*chars)
 
+    # Create initial program state with symbolic stdin
+    project = angr.Project("./chal", auto_load_libs=False)
+    state = project.factory.full_init_state(
+        stdin=angr.SimFileStream(name='stdin', content=sym_input, has_end=True)
+    )
+
+    # Constrain characters to be printable ASCII (optional but good practice)
+    for c in chars:
+        state.solver.add(c >= 0x20)
+        state.solver.add(c <= 0x7e)
+
+    # Setup simulation manager
+    simgr = project.factory.simgr(state)
+
+    # Explore only until we see the success message
+    simgr.explore(find=lambda s: b"Correct!" in s.posix.dumps(1),
+                  avoid=lambda s: b"Wrong key!" in s.posix.dumps(1))
+
+    # Extract solution
+    if simgr.found:
+        found = simgr.found[0]
+        result = found.solver.eval(sym_input, cast_to=bytes)
+        sys.stdout.buffer.write(result + b"\n")
+    else:
+        print("No solution found", file=sys.stderr)
+        sys.exit(1)
 
 if __name__ == '__main__':
     main()