diff --git a/receiver/challenges/test_phew_standalone.py b/receiver/challenges/test_phew_standalone.py new file mode 100644 index 0000000..6f10e36 --- /dev/null +++ b/receiver/challenges/test_phew_standalone.py @@ -0,0 +1,182 @@ +from .Challenge import Challenge + +import subprocess +import time +import re +import os + +class PailierBingo(Challenge): + flag_location = 'flags/phew.txt' + history_location = 'history/phew.txt' + + _CONTAINER = "pailier_container" # <-- set to your container name + _SERVICE_CMD = ["docker", "exec", "-i", _CONTAINER, "python3", "/usr/local/bin/chall.py"] + _HEX_RE = re.compile(r'^[0-9a-fA-F]+$') + + def _read_container_flag(self) -> str: + out = subprocess.run(["docker", "exec", self._CONTAINER, "cat", "/flag.txt"], + capture_output=True, text=True) + if out.returncode != 0 or not out.stdout.strip(): + raise FileNotFoundError("Flag not found in container (/flag.txt)") + return out.stdout.strip() + + def _spawn(self): + return subprocess.Popen( + self._SERVICE_CMD, + stdin=subprocess.PIPE, + stdout=subprocess.PIPE, + stderr=subprocess.STDOUT, + text=True, + bufsize=0, + ) + + def _read_until(self, proc, token, timeout=5.0, max_bytes=1_000_000): + start = time.time() + buf = [] + r = proc.stdout.read + while True: + if time.time() - start > timeout: + tail = ''.join(buf)[-500:] + raise TimeoutError(f"Timeout waiting for '{token}'. Got so far:\n{tail}") + ch = r(1) + if ch == "" and proc.poll() is not None: + raise RuntimeError(f"Process ended while waiting for '{token}'. Output:\n{''.join(buf)}") + buf.append(ch) + if len(buf) > max_bytes: + raise RuntimeError("Exceeded max read size") + if token in "".join(buf): + return "".join(buf) + + def _send_line(self, proc, s: str): + proc.stdin.write(s + "\n") + proc.stdin.flush() + + def _expect_hex_field(self, text: str, label: str) -> str: + """ + Extracts 'ct : ' or 'pt : ' (label = 'ct' or 'pt') + The service prints with spaces around the colon: 'ct : ' + """ + m = re.search(rf"{re.escape(label)}\s*:\s*([0-9a-fA-F]+)", text) + assert m, f"Missing '{label}' in output. Tail:\n{text[-400:]}" + hx = m.group(1) + assert self._HEX_RE.match(hx), f"{label} is not hex" + return hx + + def distribute(self, flag): + try: + os.makedirs(os.path.dirname(self.flag_location), exist_ok=True) + with open(self.flag_location, 'w') as f: + f.write(flag) + + os.makedirs(os.path.dirname(self.history_location), exist_ok=True) + with open(self.history_location, 'a') as f: + f.write(flag + '\n') + + self.logger.info(f'Flag {flag} written to {self.flag_location}') + return True + except Exception as e: + self.logger.error(f'Could not write flag to {self.flag_location}: {e}') + return False + + def check(self): + try: + with open(self.flag_location, 'r') as f: + host_flag = f.read().strip() + container_flag = self._read_container_flag() + assert host_flag == container_flag, 'Flag mismatch between host and container' + self.logger.info('[ok] flag parity (phew)') + + proc = self._spawn() + + def menu(): + self._read_until(proc, "> ", timeout=5.0) + + menu() + self._send_line(proc, "1") + self._read_until(proc, "pt (hex)", timeout=3.0) + self._read_until(proc, "> ", timeout=3.0) + pt_hex = "414243444546" # "ABCDEF" + self._send_line(proc, pt_hex) + out = self._read_until(proc, "\n", timeout=3.0) + ct_hex = self._expect_hex_field(out, "ct") + self.logger.info("[ok] encrypt(1) produced hex CT") + + menu() + self._send_line(proc, "3") + self._read_until(proc, "ct (hex)", timeout=3.0) + self._read_until(proc, "> ", timeout=3.0) + self._send_line(proc, ct_hex) + out_dec = self._read_until(proc, "\n", timeout=3.0) + pt_back_hex = self._expect_hex_field(out_dec, "pt") + # Normalize leading zeros for comparison + def norm(h): return (h.lstrip("0") or "0").lower() + assert norm(pt_back_hex) == norm(pt_hex), f"decrypt(encrypt(pt)) mismatch: {pt_back_hex} != {pt_hex}" + self.logger.info("[ok] decrypt(3) round-trip") + + menu() + self._send_line(proc, "1") + self._read_until(proc, "pt (hex)", timeout=3.0) + self._read_until(proc, "> ", timeout=3.0) + same_pt = "01" * 8 + self._send_line(proc, same_pt) + out_a = self._read_until(proc, "\n", timeout=3.0) + ct_a = self._expect_hex_field(out_a, "ct") + + menu() + self._send_line(proc, "1") + self._read_until(proc, "pt (hex)", timeout=3.0) + self._read_until(proc, "> ", timeout=3.0) + self._send_line(proc, same_pt) + out_b = self._read_until(proc, "\n", timeout=3.0) + ct_b = self._expect_hex_field(out_b, "ct") + + assert ct_a.lower() != ct_b.lower(), "Encryption appears deterministic for same plaintext" + self.logger.info("[ok] encrypt(1) randomness") + + menu() + self._send_line(proc, "2") + out2a = self._read_until(proc, "\n", timeout=3.0) + bingo1 = self._expect_hex_field(out2a, "ct") + + menu() + self._send_line(proc, "2") + out2b = self._read_until(proc, "\n", timeout=3.0) + bingo2 = self._expect_hex_field(out2b, "ct") + + assert bingo1.lower() != bingo2.lower(), "Bingo ciphertexts reused randomness" + self.logger.info("[ok] bingo(2) randomness") + + menu() + self._send_line(proc, "1") + self._read_until(proc, "pt (hex)", timeout=3.0) + self._read_until(proc, "> ", timeout=3.0) + pt_hex2 = "deadbeef" + self._send_line(proc, pt_hex2) + out_enc2 = self._read_until(proc, "\n", timeout=3.0) + ct2 = self._expect_hex_field(out_enc2, "ct") + + menu() + self._send_line(proc, "3") + self._read_until(proc, "ct (hex)", timeout=3.0) + self._read_until(proc, "> ", timeout=3.0) + self._send_line(proc, ct2) + out_dec2 = self._read_until(proc, "\n", timeout=3.0) + pt2_back = self._expect_hex_field(out_dec2, "pt") + assert norm(pt2_back) == norm(pt_hex2), f"decrypt(encrypt(pt2)) mismatch: {pt2_back} != {pt_hex2}" + self.logger.info("[ok] decrypt(3) round-trip (case 2)") + + menu() + self._send_line(proc, "4") + try: + proc.wait(timeout=2.0) + except subprocess.TimeoutExpired: + proc.kill() + raise AssertionError("Program did not exit after option 4") + self.logger.info("[ok] service exit on 4") + + self.logger.info('Check passed for phew') + return True + + except Exception as e: + self.logger.error(f'Could not check phew: {e}') + return False