From 419559a86f4ab6ad59ce50b3e1d7f9d939013584 Mon Sep 17 00:00:00 2001
From: Sunil Mohan Adapa <sunil@medhas.org>
Date: Fri, 17 Jan 2020 18:52:33 -0800
Subject: [PATCH] wireguard: Show public key even when connection is not active

When wireguard interface is not active 'wg show' does not provide any
information. In such case, get the public key by computing it from private key
by calling 'wg pubkey'.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>
---
 .../modules/wireguard/templates/wireguard.html  |  6 +++++-
 plinth/modules/wireguard/utils.py               | 17 ++++++++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/plinth/modules/wireguard/templates/wireguard.html b/plinth/modules/wireguard/templates/wireguard.html
index c684a6101..8006611c8 100644
--- a/plinth/modules/wireguard/templates/wireguard.html
+++ b/plinth/modules/wireguard/templates/wireguard.html
@@ -62,7 +62,11 @@
     {% blocktrans %}
       Public key for this {{ box_name }}:
     {% endblocktrans %}
-    <pre>{{ server.public_key }}</pre>
+    {% if server.public_key %}
+      <pre>{{ server.public_key }}</pre>
+    {% else %}
+      <p>{% trans "Not configured yet." %}</p>
+    {% endif %}
   </p>
 
   <a title="{% trans 'Add a new peer' %}"
diff --git a/plinth/modules/wireguard/utils.py b/plinth/modules/wireguard/utils.py
index caf63417e..44a3e6a36 100644
--- a/plinth/modules/wireguard/utils.py
+++ b/plinth/modules/wireguard/utils.py
@@ -20,6 +20,7 @@ Utilities for managing WireGuard.
 
 import datetime
 import json
+import logging
 import subprocess
 import time
 
@@ -30,6 +31,8 @@ nm = import_from_gi('NM', '1.0')
 
 IP_TEMPLATE = '10.84.0.{}'
 
+logger = logging.getLogger(__name__)
+
 
 def get_nm_info():
     """Get information from network manager."""
@@ -93,7 +96,12 @@ def get_info():
         else:
             my_client_servers[interface] = info
 
-        if interface not in status:
+        # If the NM connection is not active but the device link is up, 'wg
+        # show' will not show any public key configured on the interface.
+        if interface not in status or (interface in status and
+                                       not status[interface]['public_key']):
+            info['public_key'] = _get_public_key_from_private_key(
+                info['private_key'])
             continue
 
         info['public_key'] = status[interface]['public_key']
@@ -135,6 +143,12 @@ def enable_connections(enable):
                 pass  # Connection is already inactive
 
 
+def _get_public_key_from_private_key(private_key):
+    process = subprocess.run(['wg', 'pubkey'], check=True, capture_output=True,
+                             input=private_key.encode())
+    return process.stdout.decode()
+
+
 def _generate_private_key():
     """Return a private key generated by 'wg' command."""
     process = subprocess.run(['wg', 'genkey'], check=True, capture_output=True)
@@ -209,6 +223,7 @@ def setup_server():
         }
     }
     network.add_connection(settings)
+    logger.info('Created new WireGuard server connection')
 
 
 def _get_next_available_ip_address(settings):