gui CHANGE prove of concept use of socket.io

Use socket.io interface to do hostcheck while connecting to a NETCONF device.

Author: rkrejci

backend/connections.py

@@ -7,8 +7,11 @@
 import json
 import os
 
-from liberouterapi import auth
+from liberouterapi import socketio, auth
 from flask import request
+from flask_socketio import emit
+from eventlet import event
+from eventlet.timeout import Timeout
 import yang
 import netconf2 as nc
 
@@ -18,10 +21,39 @@
 from .data import *
 
 sessions = {}
+hostcheck = {}
+
+
+def hostkey_check_send(data):
+	print(json.dumps(data))
+	try:
+		e = hostcheck[data['id']]
+		e.send(data['result'])
+	except KeyError:
+		pass
+
+
+@socketio.on('hostcheck_result')
+def hostkey_check_answer(data):
+	hostkey_check_send(data)
+
 
 def hostkey_check(hostname, state, keytype, hexa, priv):
-	# TODO real check
-	return True
+	params = {'id': priv, 'hostname' : hostname, 'state' : state, 'keytype' : keytype, 'hexa' : hexa}
+	socketio.emit('hostcheck', params, callback = hostkey_check_send)
+
+	timeout = Timeout(30)
+	try:
+		e = hostcheck[priv] = event.Event()
+		result = e.wait()
+	except Timeout:
+		return False;
+	finally:
+		hostcheck.pop(priv, None)
+		timeout.cancel()
+
+	return result
+
 
 @auth.required()
 def connect():
@@ -45,19 +77,19 @@ def connect():
 	nc.setSearchpath(path)
 
 	ssh = nc.SSH(device['username'], password=device['password'])
-	ssh.setAuthHostkeyCheckClb(hostkey_check)
+	ssh.setAuthHostkeyCheckClb(hostkey_check, session['session_id'])
 	try:
-		session = nc.Session(device['hostname'], device['port'], ssh)
+		ncs = nc.Session(device['hostname'], device['port'], ssh)
 	except Exception as e:
 		return(json.dumps({'success': False, 'error-msg': str(e)}))
 
 	if not user.username in sessions:
 		sessions[user.username] = {}
 
 	# use key (as hostname:port:session-id) to store the created NETCONF session
-	key = session.host + ":" + str(session.port) + ":" + session.id
+	key = ncs.host + ":" + str(ncs.port) + ":" + ncs.id
 	sessions[user.username][key] = {}
-	sessions[user.username][key]['session'] = session
+	sessions[user.username][key]['session'] = ncs
 
 	return(json.dumps({'success': True, 'session-key': key}))
 

frontend/inventory/devices.component.html

@@ -60,6 +60,16 @@
   <hr/>
 </div>
 
+<div *ngIf="hostcheck" class="user-dialogue">
+    <div *ngIf="hostcheck.msg">{{hostcheck.msg}}</div>
+    <div>The authenticity of the host <span class="keyword">{{hostcheck.hostname}}</span> cannot be established.<br/>
+    <span class="keyword">{{hostcheck.keytype}}</span> key fingerprint is <span class="keyword">{{hostcheck.hexa}}</span>.</div>
+    <div>Are you sure you want to continue connecting?
+        <button (click)="hostcheckAnswer(true)">yes</button> /
+        <button (click)="hostcheckAnswer(false)">no</button>
+    </div>
+</div>
+
 <p class="msg-failure msg-rounded" *ngIf="err_msg"><span class="msg-close" (click)="err_msg=''">x</span>{{err_msg}}</p>
 <table class="items">
   <tr class="item_header">

frontend/inventory/devices.component.ts

@@ -8,6 +8,15 @@ import {Device} from './device';
 import {DevicesService} from './devices.service'
 import {SessionsService} from '../config/sessions.service'
 
+import {SocketService} from 'app/services/socket.service';
+
+enum ssh_hostcheck_status {
+    SSH_SERVER_KNOWN_CHANGED = 2,
+    SSH_SERVER_FOUND_OTHER = 3,
+    SSH_SERVER_FILE_NOT_FOUND = 4,
+    SSH_SERVER_NOT_KNOWN = 0
+}
+
 @Component({
     selector: 'inventoryDevices',
     templateUrl: './devices.component.html',
@@ -24,10 +33,12 @@ export class InventoryDevicesComponent implements OnInit {
     namePlaceholder: string = "";
     id: number;
     err_msg = "";
+    hostcheck = null;
 
     constructor(
         private devicesService: DevicesService,
         private sessionsService: SessionsService,
+        public socketService: SocketService,
         private router: Router) {}
 
     getDevices(): void {
@@ -109,15 +120,32 @@ export class InventoryDevicesComponent implements OnInit {
         }
     }
 
+    hostcheckAnswer(result: boolean) {
+        this.socketService.send('hostcheck_result', {'id': this.hostcheck.id, 'result': result});
+        delete this.hostcheck;
+    }
+
     connect(device: Device) {
         /* for backward compatibility */
         if (!device.name) {
             device.name = device.hostname + ":" + device.port;
         }
+        this.socketService.listen('hostcheck').subscribe((message: any) => {
+            this.hostcheck = message;
+            switch(message['state']) {
+            case ssh_hostcheck_status.SSH_SERVER_KNOWN_CHANGED:
+                this.hostcheck['msg'] = "Server has changed.";
+                break;
+            case ssh_hostcheck_status.SSH_SERVER_NOT_KNOWN:
+                this.hostcheck['msg'] = "Server not known.";
+                break;
+            }
+        });
         this.sessionsService.connect(device).subscribe(result => {
             if (result['success']) {
                 this.router.navigateByUrl('/netopeer/config');
             } else {
+                delete this.hostcheck;
                 this.err_msg = result['error-msg']
             }
         });

frontend/package.json

@@ -14,7 +14,7 @@
   },
   "homepage": "https://github.com/CESNET/Netopeer2GUI",
   "dependencies" : {
-    "@angular/material": "^5.0.0",
-    "@angular/cdk": "^5.0.0"
+    "@angular/material": "^6.0.0",
+    "@angular/cdk": "^6.0.0"
   }
 }