demo: add option to test HMAC

The option '-m' is added to the demo to check that nodes have called
babeld with the current HMAC configuration.

demo/demo

 #!/usr/bin/python2
 import argparse, math, nemu, os, re, signal
-import socket, subprocess, sys, time, weakref
+import socket, sqlite3, subprocess, sys, time, weakref
 from collections import defaultdict
 from contextlib import contextmanager
+from threading import Thread
 IPTABLES = 'iptables'
 SCREEN = 'screen'
 VERBOSE = 4
@@ -60,6 +61,8 @@ parser.add_argument('-d', '--duration', type = int,
     help = 'time of the demo execution in seconds')
 parser.add_argument('-p', '--ping', action = 'store_true',
     help = 'execute ping utility')
+parser.add_argument('-m', '--hmac', action = 'store_true',
+    help = 'execute HMAC test')
 args = parser.parse_args()
 
 def handler(signum, frame):
@@ -243,7 +246,8 @@ def new_network(registry, reg_addr, serial, ca):
         """)).wait()
     db = sqlite3.connect(db_path, isolation_level=None)
     def new_node(node, folder, args='', prefix_len=None, registry=registry_url):
-        nodes.append(node)
+        if node not in nodes:
+            nodes.append(node)
         if not os.path.exists(folder + '/cert.crt'):
             dh_path = folder + '/dh2048.pem'
             if not os.path.exists(dh_path):
@@ -297,6 +301,46 @@ if args.ping:
         name = machine.name if machine.short[0] == 'R' else 'm' + machine.short
         machine.screen('python ping.py {} {}'.format(name, ' '.join(ips)))
 
+class testHMAC(Thread):
+
+    def run(self):
+        reg1_db = sqlite3.connect('registry/registry.db', isolation_level=None,
+                                                 check_same_thread=False)
+        reg2_db = sqlite3.connect('registry2/registry.db', isolation_level=None,
+                                                 check_same_thread=False)
+        reg1_db.text_factory = reg2_db.text_factory = str
+        m_net1 = ['registry', 'm1', 'm2', 'm3', 'm4', 'm5', 'm6', 'm7', 'm8']
+        m_net2 = ['registry2', 'm10']
+        print 'Testing HMAC, letting the time to machines to create tunnels...'
+        time.sleep(45)
+        print 'Check that the initial HMAC config is deployed on network 1'
+        test_hmac.checkHMAC(reg1_db, m_net1)
+        print 'Test that a HMAC update works with nodes that are up'
+        registry.screen('wget http://10.0.0.2/updateHMAC')
+        print 'Updated HMAC (config = hmac0 & hmac1), waiting...'
+        time.sleep(60)
+        print 'Checking HMAC on machines connected to registry 1...'
+        test_hmac.checkHMAC(reg1_db, m_net1)
+        print ('Test that machines can update upon reboot ' +
+               'when they were off during a HMAC update.')
+        test_hmac.killRe6st('m1')
+        print 'Re6st on machine 1 is stopped'
+        time.sleep(5)
+        registry.screen('wget http://10.0.0.2/updateHMAC')
+        print 'Updated HMAC on registry (config = hmac1 & hmac2), waiting...'
+        time.sleep(60)
+        new_node(machine1, 'm1', '-I%s' % m1_if_0.name,
+                 None, 'http://%s/' % REGISTRY)
+        print 'Started re6st on machine 1, waiting for it to get new conf'
+        time.sleep(60)
+        print 'Checking HMAC on machines connected to registry 1...'
+        test_hmac.checkHMAC(reg1_db, m_net1)
+        print 'Testing of HMAC done!'
+
+if args.hmac:
+    import test_hmac
+    testHMAC().start()
+
 _ll = {}
 def node_by_ll(addr):
     try:

demo/test_hmac.py

+import sqlite3, subprocess
+
+def getConfig(db, name):
+    r, = next(db.execute(
+              "SELECT value FROM config WHERE name=?", (name,)), (None,))
+    if r is not None:
+        r = str(r).encode('hex')
+    return r
+
+def killRe6st(machine):
+    p = subprocess.Popen(['pgrep', '-f', 'set ./py re6stnet @%s' %machine],
+                         stdout=subprocess.PIPE)
+    ps_id = p.communicate()[0].split('\n', 1)[0]
+    if ps_id:
+        subprocess.Popen(['kill', ps_id])
+
+def checkHMAC(db, machines):
+    hmac = dict([(k, getConfig(db, k))
+                for k in 'babel_hmac0', 'babel_hmac1', 'babel_hmac2'])
+    rc = True
+    ps = subprocess.Popen(['pgrep', '-a', 'babel'], stdout=subprocess.PIPE)
+    for p in (p for p in ps.communicate()[0].split('\n') if p):
+        if p.split('/',1)[0].split()[-1] in machines:
+            if hmac['babel_hmac0'] and not hmac['babel_hmac1']: # state = hmac0
+                if ('sign' not in p or
+                    'accept' in p or
+                    p.split('sign value ',1)[1].split()[0]\
+                      != hmac['babel_hmac0']):
+                    rc = False
+                    print 'HMAC config wrong for in %s' % p
+            else:
+                if hmac['babel_hmac0']: # state = hmac0 and hmac1
+                    sign = 'babel_hmac0'
+                    accept = 'babel_hmac1'
+                else: # state = hmac1 and hmac2
+                    sign = 'babel_hmac1'
+                    accept = 'babel_hmac2'
+                if ('accept' not in p or
+                    'sign' not in p or
+                    p.split('sign value ',1)[1].split()[0] != hmac[sign] or
+                    p.split('accept value ',1)[1].split()[0] != hmac[accept]):
+                    rc = False
+                    print 'HMAC config wrong in %s' % p
+    if rc:
+        print('All nodes use Babel with the correct HMAC configuration')
+    else:
+        print('Correct config: %s' % hmac)
+    return rc