first commit

check_clear_smtp.py

@@ -0,0 +1,120 @@
+#!/usr/bin/python3
+from string import ascii_lowercase
+from random import choices
+from argparse import ArgumentParser
+from smtplib import (
+    SMTP,
+    SMTPSenderRefused,
+    SMTPRecipientsRefused,
+)
+
+
+def check_clear(domain, port, orgin_domain, from_addr, to_addr, log_level):
+    with SMTP(host=domain, port=port, local_hostname=orgin_domain) as smtp:
+        smtp.set_debuglevel(log_level)
+        try:
+            smtp.sendmail(
+                from_addr=from_addr,
+                to_addrs=[to_addr],
+                msg="test_cleartextmail"
+            )
+        except SMTPSenderRefused as error:
+            code = error.smtp_code
+            error = error.smtp_error.decode()
+            if code == 530 and "STARTTLS" in error:
+                return False
+            else:
+                raise
+        except SMTPRecipientsRefused:
+            pass
+        return True
+
+
+def color(string, color_name):
+    color_code = ""
+    if color_name == "green":
+        color_code = "\033[92m"
+    elif color_name == "red":
+        color_code = "\033[91m"
+    elif color_name == "orange":
+        color_code = "\033[93m"
+    end_color = "\033[1m"
+    return f"{color_code}{string}{end_color}"
+
+
+def main():
+    parser = ArgumentParser(
+        description=(
+            "Script to check wether or not the target mail server accepts "
+            "cleartext connections and email from other smtp relay"
+        )
+    )
+    parser.add_argument(
+        'domain',
+        type=str,
+        help="domain to check"
+    )
+
+    parser.add_argument(
+        '-p',
+        '--port',
+        type=int,
+        default=25,
+        help="port for STARTTLS (usually 25)",
+    )
+    parser.add_argument(
+        '-f',
+        '--from_addr',
+        type=str,
+        default="foo@example.com",
+        help="address to use to check the server (default foo@example.com)"
+    )
+    parser.add_argument(
+        '-t',
+        '--to_addr',
+        type=str,
+        default="",
+        help="address of the recipient (default [random]@[domain])"
+    )
+    parser.add_argument(
+        "-v",
+        "--verbose",
+        action="store_true",
+        help="Activate verbose mode an display all smtp trafic"
+    )
+
+    args = parser.parse_args()
+    origin_domain = args.from_addr.split("@")[-1]
+    rand_char = ''.join(choices(ascii_lowercase, k=64))
+    to_addr = args.to_addr if args.to_addr else f"{rand_char}@{args.domain}"
+
+    print(
+        "Testing if the server support clear text email delivery:",
+        end=' '
+    )
+
+    try:
+        result = check_clear(
+            domain=args.domain,
+            port=args.port,
+            orgin_domain=origin_domain,
+            from_addr=args.from_addr,
+            to_addr=to_addr,
+            log_level=2 if args.verbose else 0
+        )
+    except Exception as exception:
+        print(color("Unknown", "orange"))
+        print(
+            "got unknown exception run the command again with -v for more "
+            "details"
+        )
+        print(exception)
+    else:
+        if result:
+            print(color("True", "green"))
+        else:
+            print(color("False", "red"))
+
+
+if __name__ == "__main__":
+    main()