cert_deets.py

@@ -1,13 +1,12 @@
-"""Display TLS certificate details for an HTTP endpoint."""
-
-from __future__ import annotations
-
+#!python3
+"""
+Return the Akamai property and version for a given site
+"""
 import argparse
 import socket
 import ssl
 import sys
 import urllib.error
-from contextlib import suppress
 from typing import Any
 from urllib.parse import urlparse
 
@@ -21,7 +20,8 @@ SAN_GROUPING = 4
 
 
 def get_cert_with_servername(addr: tuple[str, int], servername: str = "") -> bytes:
-    """Get TLS certificate from an address with an explicit servername override.
+    """
+    Get TLS certificate from an address with an explicit servername override
 
     Args:
         addr (tuple[str, int]): adress in tuple form (address, port)
@@ -29,49 +29,51 @@ def get_cert_with_servername(addr: tuple[str, int], servername: str = "") -> byt
 
     Returns:
         bytes: PEM bytes
-
     """
     context = ssl.create_default_context()
     context.check_hostname = False
 
-    with socket.create_connection((addr[0], addr[1]), timeout=10) as sock, context.wrap_socket(
-        sock,
-        server_hostname=servername,
-    ) as sslsock:
-        if der_cert := sslsock.getpeercert(binary_form=True):
-            return ssl.DER_cert_to_PEM_cert(der_cert).encode("utf=8")
+    with socket.create_connection((addr[0], addr[1]), timeout=10) as sock:
+        with context.wrap_socket(sock, server_hostname=servername) as sslsock:
+            if der_cert := sslsock.getpeercert(True):
+                return ssl.DER_cert_to_PEM_cert(der_cert).encode("utf=8")
 
-    return b""
+    return bytes()
 
 
 def format_fingerprint(fingerprint: bytes | str) -> str:
-    """Print a fingerprint as a colon-separated hex string.
+    """
+    Print a fingerprint as a colon-separated hex string
 
     Args:
         fingerprint (bytes | str): fingerprint to format
 
     Returns:
         str: formatted fingerprint
-
     """
     if isinstance(fingerprint, str):
         fingerprint = bytearray.fromhex(fingerprint)
     return ":".join([format(i, "02x") for i in fingerprint])
 
 
-def display_error(site: str, error: Any = None) -> None:
-    """Print a generic error."""
+def display_error(
+    site: str,
+    error: Any = None,
+) -> None:
+    """
+    Print a generic error
+    """
     print(f"ERROR: Could not find a certificate for {site}")
     if error:
         print(str(error))
 
 
 def parseargs() -> argparse.Namespace:
-    """Parse the CLI.
+    """
+    Parse the CLI
 
     Returns:
         argparse.Namespace: parsed arguments
-
     """
     parser = argparse.ArgumentParser()
 
@@ -82,11 +84,11 @@ def parseargs() -> argparse.Namespace:
 
 
 def main() -> int:
-    """Run the code.
+    """
+    Main entrypoint
 
     Returns:
         int: return value
-
     """
     args = parseargs()
 
@@ -121,8 +123,10 @@ def main() -> int:
             ).encode("utf-8")
 
         cert_chain = CertificateChain()
-        with suppress(urllib.error.URLError):
+        try:
             cert_chain = resolve(pem_data)
+        except urllib.error.URLError:
+            pass
     except (
         ConnectionRefusedError,
         ConnectionResetError,
@@ -142,20 +146,23 @@ def main() -> int:
 
     sans = [
         f"DNS:{dns}"
-        for dns in cert.extensions.get_extension_for_class(x509.SubjectAlternativeName).value.get_values_for_type(
-            x509.DNSName,
-        )
+        for dns in cert.extensions.get_extension_for_class(
+            x509.SubjectAlternativeName
+        ).value.get_values_for_type(x509.DNSName)
     ]
     sans.extend(
         [
             f"IP:{ip}"
-            for ip in cert.extensions.get_extension_for_class(x509.SubjectAlternativeName).value.get_values_for_type(
-                x509.IPAddress,
-            )
-        ],
+            for ip in cert.extensions.get_extension_for_class(
+                x509.SubjectAlternativeName
+            ).value.get_values_for_type(x509.IPAddress)
+        ]
     )
 
-    sangroups = [sans[group : group + SAN_GROUPING] for group in range(0, len(sans), SAN_GROUPING)]
+    sangroups = [
+        sans[group : group + SAN_GROUPING]
+        for group in range(0, len(sans), SAN_GROUPING)
+    ]
 
     table = [
         ["Common name", cert.subject.rfc4514_string()],
@@ -165,8 +172,7 @@ def main() -> int:
         ["Issuer", cert.issuer.rfc4514_string()],
         [
             "Fingerprint",
-            f"{format_fingerprint(cert.fingerprint(hashes.SHA1()))} (SHA1)\n"
-            f"{format_fingerprint(cert.fingerprint(hashes.SHA256()))} (SHA256)\n",
+            f"{format_fingerprint(cert.fingerprint(hashes.SHA1()))} (SHA1)",
         ],
     ]
 
@@ -178,14 +184,13 @@ def main() -> int:
                     [
                         f"{cert.common_name} "
                         f"(Issuer: {cert.issuer})\n"
-                        "Fingerprint: \n"
-                        f"\t{format_fingerprint(cert.get_fingerprint(hashes.SHA1))} (SHA1)\n"
-                        f"\t{format_fingerprint(cert.get_fingerprint(hashes.SHA256))} (SHA256)"
-                        for cert in [*list(cert_chain.intermediates), cert_chain.root]
+                        "Fingerprint: "
+                        f"{format_fingerprint(cert.get_fingerprint(hashes.SHA1))} (SHA1)"
+                        for cert in list(cert_chain.intermediates) + [cert_chain.root]
                         if cert
-                    ],
+                    ]
                 ),
-            ],
+            ]
         )
 
     print(tabulate(table, tablefmt="plain"))