ssh: T2635: harden Jinja2 template and daemon startup

3 files changed, 22 insertions, 25 deletions

diff --git a/data/templates/ssh/sshd_config.tmpl b/data/templates/ssh/sshd_config.tmpl
index 1dc700d38..7d7257cae 100644
--- a/data/templates/ssh/sshd_config.tmpl
+++ b/data/templates/ssh/sshd_config.tmpl
@@ -48,59 +48,59 @@ LogLevel {{ loglevel | upper }}
 # Specifies whether password authentication is allowed
 PasswordAuthentication {{ "no" if disable_password_authentication is defined else "yes" }}
 
-{% if listen_address %}
+{% if listen_address is defined and listen_address is not none %}
 # Specifies the local addresses sshd should listen on
 {%   for address in listen_address %}
 ListenAddress {{ address }}
 {%   endfor %}
 {% endif %}
 
-{% if ciphers %}
+{% if ciphers is defined and ciphers is not none %}
 # Specifies the ciphers allowed for protocol version 2
-{% set value = ciphers if ciphers is string else ciphers | join(',') %}
+{%   set value = ciphers if ciphers is string else ciphers | join(',') %}
 Ciphers {{ value }}
 {% endif %}
 
-{% if mac %}
+{% if mac is defined and mac is not none %}
 # Specifies the available MAC (message authentication code) algorithms
-{% set value = mac if mac is string else mac | join(',') %}
+{%   set value = mac if mac is string else mac | join(',') %}
 MACs {{ value }}
 {% endif %}
 
-{% if key_exchange %}
+{% if key_exchange is defined and key_exchange is not none %}
 # Specifies the available Key Exchange algorithms
-{% set value = key_exchange if key_exchange is string else key_exchange | join(',') %}
+{%   set value = key_exchange if key_exchange is string else key_exchange | join(',') %}
 KexAlgorithms {{ value }}
 {% endif %}
 
-{% if access_control is defined %}
-{%   if access_control.allow is defined %}
+{% if access_control is defined and access_control is not none %}
+{%   if access_control.allow is defined and access_control.allow is not none %}
 {%     if access_control.allow.user is defined %}
 # If specified, login is allowed only for user names that match
-{% set value = access_control.allow.user if access_control.allow.user is string else access_control.allow.user | join(' ') %}
+{%       set value = access_control.allow.user if access_control.allow.user is string else access_control.allow.user | join(' ') %}
 AllowUsers {{ value }}
 {%     endif %}
 {%     if access_control.allow.group is defined %}
 # If specified, login is allowed only for users whose primary group or supplementary group list matches
-{% set value = access_control.allow.group if access_control.allow.group is string else access_control.allow.group | join(' ') %}
+{%       set value = access_control.allow.group if access_control.allow.group is string else access_control.allow.group | join(' ') %}
 AllowGroups {{ value }}
 {%     endif %}
 {%   endif %}
-{%   if access_control.deny is defined %}
+{%   if access_control.deny is defined and access_control.deny is not none %}
 {%     if access_control.deny.user is defined %}
 # Login is disallowed for user names that match
-{% set value = access_control.deny.user if access_control.deny.user is string else access_control.deny.user | join(' ') %}
+{%        set value = access_control.deny.user if access_control.deny.user is string else access_control.deny.user | join(' ') %}
 DenyUsers {{ value }}
 {%     endif %}
 {%     if access_control.deny.group is defined %}
 # Login is disallowed for users whose primary group or supplementary group list matches
-{% set value = access_control.deny.group if access_control.deny.group is string else access_control.deny.group | join(' ') %}
+{%        set value = access_control.deny.group if access_control.deny.group is string else access_control.deny.group | join(' ') %}
 DenyGroups {{ value }}
 {%     endif %}
 {%   endif %}
 {% endif %}
 
-{% if client_keepalive_interval %}
+{% if client_keepalive_interval is defined and client_keepalive_interval is not none %}
 # Sets a timeout interval in seconds after which if no data has been received from the client,
 # sshd(8) will send a message through the encrypted channel to request a response from the client
 ClientAliveInterval {{ client_keepalive_interval }}
diff --git a/smoketest/scripts/cli/test_service_ssh.py b/smoketest/scripts/cli/test_service_ssh.py
index e9e4639fc..eede042de 100755
--- a/smoketest/scripts/cli/test_service_ssh.py
+++ b/smoketest/scripts/cli/test_service_ssh.py
@@ -44,11 +44,6 @@ class TestServiceSSH(unittest.TestCase):
     def tearDown(self):
         # delete testing SSH config
         self.session.delete(base_path)
-        # restore "plain" SSH access
-        self.session.set(base_path)
-        # delete VRF
-        self.session.delete(['vrf', 'name', vrf])
-
         self.session.commit()
         del self.session
 
@@ -109,7 +104,7 @@ class TestServiceSSH(unittest.TestCase):
     def test_ssh_multiple_listen_addresses(self):
         # Check if SSH service can be configured and runs with multiple
         # listen ports and listen-addresses
-        ports = ['22', '2222']
+        ports = ['22', '2222', '2223', '2224']
         for port in ports:
             self.session.set(base_path + ['port', port])
 
@@ -143,7 +138,7 @@ class TestServiceSSH(unittest.TestCase):
         with self.assertRaises(ConfigSessionError):
             self.session.commit()
 
-        self.session.set(['vrf', 'name', vrf, 'table', '1001'])
+        self.session.set(['vrf', 'name', vrf, 'table', '1338'])
 
         # commit changes
         self.session.commit()
@@ -159,5 +154,8 @@ class TestServiceSSH(unittest.TestCase):
         tmp = cmd(f'ip vrf pids {vrf}')
         self.assertIn(PROCESS_NAME, tmp)
 
+        # delete VRF
+        self.session.delete(['vrf', 'name', vrf])
+
 if __name__ == '__main__':
     unittest.main(verbosity=2)
diff --git a/src/conf_mode/ssh.py b/src/conf_mode/ssh.py
index 07c057fd7..28e606663 100755
--- a/src/conf_mode/ssh.py
+++ b/src/conf_mode/ssh.py
@@ -68,6 +68,8 @@ def generate(ssh):
 
     render(config_file, 'ssh/sshd_config.tmpl', ssh)
     render(systemd_override, 'ssh/override.conf.tmpl', ssh)
+    # Reload systemd manager configuration
+    call('systemctl daemon-reload')
 
     return None
 
@@ -76,9 +78,6 @@ def apply(ssh):
         # SSH access is removed in the commit
         call('systemctl stop ssh.service')
 
-    # Reload systemd manager configuration
-    call('systemctl daemon-reload')
-
     if ssh:
         call('systemctl restart ssh.service')