Make hostwatch find both fqdn and hostname

Currently hostwatch only adds hostnames even when FQDNs are available.
This commit changes found_host so that when the name is a FQDN, both the FQDN
and an hostname are added, e.g., given api.foo.com both api and api.foo.com
will be added.

Fixes #151 if merged.

N.B.: I rarely use hostwatch, it would probably be a good idea to get feedback
from people who actually use it before merging. Not too sure about this...

sshuttle/client.py

@@ -298,7 +298,7 @@ class FirewallClient:
             raise Fatal('%r expected STARTED, got %r' % (self.argv, line))
 
     def sethostip(self, hostname, ip):
-        assert(not re.search(b'[^-\w]', hostname))
+        assert(not re.search(b'[^-\w\.]', hostname))
         assert(not re.search(b'[^0-9.]', ip))
         self.pfile.write(b'HOST %s,%s\n' % (hostname, ip))
         self.pfile.flush()

sshuttle/hostwatch.py

@@ -61,23 +61,27 @@ def read_host_cache():
         words = line.strip().split(',')
         if len(words) == 2:
             (name, ip) = words
-            name = re.sub(r'[^-\w]', '-', name).strip()
+            name = re.sub(r'[^-\w\.]', '-', name).strip()
             ip = re.sub(r'[^0-9.]', '', ip).strip()
             if name and ip:
                 found_host(name, ip)
 
 
-def found_host(hostname, ip):
-    hostname = re.sub(r'\..*', '', hostname)
-    hostname = re.sub(r'[^-\w]', '_', hostname)
+def found_host(name, ip):
+    hostname = re.sub(r'\..*', '', name)
+    hostname = re.sub(r'[^-\w\.]', '_', hostname)
     if (ip.startswith('127.') or ip.startswith('255.') or
             hostname == 'localhost'):
         return
-    oldip = hostnames.get(hostname)
+
+    if hostname != name:
+        found_host(hostname, ip)
+
+    oldip = hostnames.get(name)
     if oldip != ip:
-        hostnames[hostname] = ip
-        debug1('Found: %s: %s\n' % (hostname, ip))
-        sys.stdout.write('%s,%s\n' % (hostname, ip))
+        hostnames[name] = ip
+        debug1('Found: %s: %s\n' % (name, ip))
+        sys.stdout.write('%s,%s\n' % (name, ip))
         write_host_cache()