chore: Update self-signed certificate verification logic

This commit updates the self-signed certificate generation logic in the `generate_cert` function. It includes handling the `not_valid_after_utc` and `not_valid_before_utc` attributes of the certificate, checking if the subject of the certificate matches the configuration, and verifying the expiration date of the certificate. These updates ensure the proper generation and validation of self-signed certificates.

src/common/core/selfsigned/jobs/self-signed.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 
-from datetime import datetime, timedelta
+from datetime import datetime, timedelta, timezone
 from os import getenv, sep
 from os.path import join
 from pathlib import Path
@@ -42,13 +42,21 @@ def generate_cert(first_server: str, days: str, subj: str, self_signed_path: Pat
             LOGGER.info(f"Self-signed certificate already present for {first_server}")
 
             certificate = x509.load_pem_x509_certificate(JOB.get_cache("cert.pem", service_id=first_server), default_backend())
+
+            try:
+                not_valid_after = certificate.not_valid_after_utc
+                not_valid_before = certificate.not_valid_before_utc
+            except AttributeError:
+                not_valid_after = certificate.not_valid_after
+                not_valid_before = certificate.not_valid_before
+
             if sorted(attribute.rfc4514_string() for attribute in certificate.subject) != sorted(v for v in subj.split("/") if v):
                 LOGGER.warning(f"Subject of self-signed certificate for {first_server} is different from the one in the configuration, regenerating ...")
-            elif certificate.not_valid_after_utc - certificate.not_valid_before_utc != timedelta(days=int(days)):
+            elif not_valid_after - not_valid_before != timedelta(days=int(days)):
                 LOGGER.warning(
                     f"Expiration date of self-signed certificate for {first_server} is different from the one in the configuration, regenerating ..."
                 )
-            elif certificate.not_valid_after_utc < datetime.now(tz=certificate.not_valid_after_utc.timetz().tzinfo):
+            elif not_valid_after < datetime.now(tz=timezone.utc):
                 LOGGER.warning(f"Self-signed certificate for {first_server} has expired, regenerating ...")
             else:
                 LOGGER.info(f"Self-signed certificate for {first_server} is valid")