From 90d9cc0b1f5253c1aa02218e7036be7f6f10c650 Mon Sep 17 00:00:00 2001
From: Patrick Cloke <patrickc@matrix.org>
Date: Thu, 18 Nov 2021 15:13:55 -0500
Subject: [PATCH 1/2] Remove dead code from acme support.

---
 synapse/config/tls.py | 50 -------------------------------------------
 1 file changed, 50 deletions(-)

diff --git a/synapse/config/tls.py b/synapse/config/tls.py
index 613faca6587e..21e5ddd15f81 100644
--- a/synapse/config/tls.py
+++ b/synapse/config/tls.py
@@ -14,7 +14,6 @@
 
 import logging
 import os
-from datetime import datetime
 from typing import List, Optional, Pattern
 
 from OpenSSL import SSL, crypto
@@ -133,55 +132,6 @@ def read_config(self, config: dict, config_dir_path: str, **kwargs):
         self.tls_certificate: Optional[crypto.X509] = None
         self.tls_private_key: Optional[crypto.PKey] = None
 
-    def is_disk_cert_valid(self, allow_self_signed=True):
-        """
-        Is the certificate we have on disk valid, and if so, for how long?
-
-        Args:
-            allow_self_signed (bool): Should we allow the certificate we
-                read to be self signed?
-
-        Returns:
-            int: Days remaining of certificate validity.
-            None: No certificate exists.
-        """
-        if not os.path.exists(self.tls_certificate_file):
-            return None
-
-        try:
-            with open(self.tls_certificate_file, "rb") as f:
-                cert_pem = f.read()
-        except Exception as e:
-            raise ConfigError(
-                "Failed to read existing certificate file %s: %s"
-                % (self.tls_certificate_file, e)
-            )
-
-        try:
-            tls_certificate = crypto.load_certificate(crypto.FILETYPE_PEM, cert_pem)
-        except Exception as e:
-            raise ConfigError(
-                "Failed to parse existing certificate file %s: %s"
-                % (self.tls_certificate_file, e)
-            )
-
-        if not allow_self_signed:
-            if tls_certificate.get_subject() == tls_certificate.get_issuer():
-                raise ValueError(
-                    "TLS Certificate is self signed, and this is not permitted"
-                )
-
-        # YYYYMMDDhhmmssZ -- in UTC
-        expiry_data = tls_certificate.get_notAfter()
-        if expiry_data is None:
-            raise ValueError(
-                "TLS Certificate has no expiry date, and this is not permitted"
-            )
-        expires_on = datetime.strptime(expiry_data.decode("ascii"), "%Y%m%d%H%M%SZ")
-        now = datetime.utcnow()
-        days_remaining = (expires_on - now).days
-        return days_remaining
-
     def read_certificate_from_disk(self):
         """
         Read the certificates and private key from disk.

From 81615c5acac95835d5b36842b86e34e0499742a1 Mon Sep 17 00:00:00 2001
From: Patrick Cloke <patrickc@matrix.org>
Date: Thu, 18 Nov 2021 15:14:20 -0500
Subject: [PATCH 2/2] Newsfragment

---
 changelog.d/11393.misc | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog.d/11393.misc

diff --git a/changelog.d/11393.misc b/changelog.d/11393.misc
new file mode 100644
index 000000000000..6bf47ec2e041
--- /dev/null
+++ b/changelog.d/11393.misc
@@ -0,0 +1 @@
+Remove dead code from supporting ACME.