patch: fix ceph dashboard subcommand becoming unavailable on crash

Adapt the patch that originally disabled certain TLS checks during the
dashboard's startup and fixes the `ceph dashboard` subcommand becoming
unavailable if the dashboard crashes during that time.

This is achieved by re-implementing certain checks and also re-raising
any other unforeseen exceptions that occur in regards to TLS as one
of Ceph's internal exception types, which are then handled by the
dashboard itself. This is akin to how these cases were handled
originally.

Also fixes a typo in the `ceph dashboard create-self-signed-cert`
command output.

Signed-off-by: Max Carrara <m.carrara@proxmox.com>

patches/0013-mgr-dashboard-remove-ability-to-create-and-check-TLS.patch

@@ -1,6 +1,6 @@
 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
 From: Max Carrara <m.carrara@proxmox.com>
-Date: Thu, 4 Jan 2024 17:37:50 +0100
+Date: Fri, 26 Jan 2024 14:04:47 +0100
 Subject: [PATCH] mgr/dashboard: remove ability to create and check TLS
  key/cert pairs
 
@@ -18,6 +18,17 @@ key/cert pair actually match, is also removed. This means that users
 need to ensure themselves that the correct pair is supplied -
 otherwise their browser will complain.
 
+Other checks unrelated to the verification of keypairs are preserved,
+such as checking for the cert's and key's existence on the filesystem.
+
+`ssl.SSLError`s that occur during startup are re-raised with the
+additional information they contain as `ServerConfigException`s, as
+the dashboard handles these in its startup loop. Other exceptions are
+re-raised as well. Otherwise, the dashboard will irrecoverably crash,
+which also causes the `ceph dashboard` subcommand to stop working
+altogether, even if one of its sub-subcommands are unrelated to the
+dashboard itself.
+
 These changes allow the dashboard to launch with TLS enabled again.
 
 [0]: https://tracker.ceph.com/issues/63529
@@ -25,11 +36,11 @@ These changes allow the dashboard to launch with TLS enabled again.
 
 Signed-off-by: Max Carrara <m.carrara@proxmox.com>
 ---
- src/pybind/mgr/dashboard/module.py | 41 ++++++++++++++++++++----------
+ src/pybind/mgr/dashboard/module.py | 58 ++++++++++++++++++++++--------
- 1 file changed, 27 insertions(+), 14 deletions(-)
+ 1 file changed, 43 insertions(+), 15 deletions(-)
 
 diff --git a/src/pybind/mgr/dashboard/module.py b/src/pybind/mgr/dashboard/module.py
-index 68725be6e35..9db55a3ee93 100644
+index 68725be6e35..c8b263d9786 100644
 --- a/src/pybind/mgr/dashboard/module.py
 +++ b/src/pybind/mgr/dashboard/module.py
 @@ -23,8 +23,7 @@ if TYPE_CHECKING:
@@ -42,25 +53,41 @@ index 68725be6e35..9db55a3ee93 100644
  
  from . import mgr
  from .controllers import Router, json_error_page
-@@ -172,11 +171,14 @@ class CherryPyConfig(object):
+@@ -172,11 +171,29 @@ class CherryPyConfig(object):
              else:
                  pkey_fname = self.get_localized_module_option('key_file')  # type: ignore
  
 -            verify_tls_files(cert_fname, pkey_fname)
--
++            if not cert_fname or not pkey_fname:
-             # Create custom SSL context to disable TLS 1.0 and 1.1.
++                raise ServerConfigException('no certificate configured')
-             context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
++
--            context.load_cert_chain(cert_fname, pkey_fname)
++            if not os.path.isfile(cert_fname):
++                raise ServerConfigException(f"Certificate {cert_fname} does not exist")
++
++            if not os.path.isfile(pkey_fname):
++                raise ServerConfigException(f"private key {pkey_fname} does not exist")
 +
 +            try:
++                # Create custom SSL context to disable TLS 1.0 and 1.1.
++                context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
 +                context.load_cert_chain(cert_fname, pkey_fname)
-+            except ssl.SSLError:
++            except ssl.SSLError as e:
-+                raise ServerConfigException("No certificate configured")
++                raise ServerConfigException(
-+
++                    "Encountered unexpected error while creating SSL context"
++                    f" - library: {e.library}, reason: {e.reason}"
++                )
++            except Exception as e:
++                raise ServerConfigException(
++                    f"Encountered unexpected error while creating SSL context: {e}"
++                )
+ 
+-            # Create custom SSL context to disable TLS 1.0 and 1.1.
+-            context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
+-            context.load_cert_chain(cert_fname, pkey_fname)
              if sys.version_info >= (3, 7):
                  if Settings.UNSAFE_TLS_v1_2:
                      context.minimum_version = ssl.TLSVersion.TLSv1_2
-@@ -473,15 +475,26 @@ class Module(MgrModule, CherryPyConfig):
+@@ -473,15 +490,26 @@ class Module(MgrModule, CherryPyConfig):
  
      @CLIWriteCommand("dashboard create-self-signed-cert")
      def set_mgr_created_self_signed_cert(self):
@@ -81,7 +108,7 @@ index 68725be6e35..9db55a3ee93 100644
 +
 +        1. Generate a private key and self-signed certificate:
 +          # openssl req -newkey rsa:2048 -nodes -x509 \\
-+          -keyout /root/dashboard-key.pem -out /root/dashboard-cert.pem -sha512 \\
++          -keyout /root/dashboard-key.pem -out /root/dashboard-crt.pem -sha512 \\
 +          -days 3650 -subj "/CN=IT/O=ceph-mgr-dashboard" -utf8
 +
 +        2. Set the corresponding config keys for the key/cert pair: