lab2 доработки

lab2/access.py

@@ -1,4 +1,5 @@
 #!/usr/bin/env python3
+import argparse
 import getpass
 import hashlib
 import shutil
@@ -195,7 +196,40 @@ def cmd_remove(args: list[str], login: str, perms: str) -> None:
     print("Done.")
 
 
+def check_credentials(login: str, password: str) -> bool:
+    """Check login+password against passwd. Used by --check mode."""
+    users = read_users()
+    user = users.get(login)
+    if user and user["password_hash"] == hash_password(password):
+        return True
+    return False
+
+
 def main() -> None:
+    parser = argparse.ArgumentParser(description="Access confidential data")
+    parser.add_argument(
+        "--check",
+        metavar="LOGIN",
+        help="Batch mode: read passwords line-by-line from stdin, output 0 or 1 per line; exit 0 on first match",
+    )
+    args, _ = parser.parse_known_args()
+
+    if args.check is not None:
+        # --check: one process, many checks; read_users once
+        users = read_users()
+        user = users.get(args.check)
+        target_hash = user["password_hash"] if user else None
+
+        for line in sys.stdin:
+            password = line.rstrip("\n")
+            if target_hash and hash_password(password) == target_hash:
+                sys.stdout.write("1\n")
+                sys.stdout.flush()
+                sys.exit(0)
+            sys.stdout.write("0\n")
+            sys.stdout.flush()
+        sys.exit(1)
+
     signal.signal(signal.SIGINT, lambda _s, _f: (print("\nBye."), sys.exit(0)))
 
     login, user = authenticate()