Updated domain name validation and unit tests

plinth/modules/config/config.py

@@ -22,9 +22,11 @@ Plinth module for configuring hostname and domainname.
 from django import forms
 from django.contrib import messages
 from django.core import validators
+from django.core.exceptions import ValidationError
 from django.template.response import TemplateResponse
 from django.utils.translation import ugettext as _, ugettext_lazy
 import logging
+import re
 import socket
 
 from plinth import actions
@@ -33,6 +35,8 @@ from plinth.signals import pre_hostname_change, post_hostname_change
 from plinth.signals import domainname_change
 
 
+HOSTNAME_REGEX = r'^[a-zA-Z0-9]([-a-zA-Z0-9]{,61}[a-zA-Z0-9])?$'
+
 LOGGER = logging.getLogger(__name__)
 
 
@@ -56,6 +60,11 @@ class TrimmedCharField(forms.CharField):
 
         return super(TrimmedCharField, self).clean(value)
 
+def domain_labelvalidator(domainname):
+    """Validating Domain Name Labels"""
+    for label in domainname.split("."):
+        if not re.match(HOSTNAME_REGEX, label):
+            raise ValidationError(ugettext_lazy('Invalid Domain Name'))
 
 class ConfigurationForm(forms.Form):
     """Main system configuration form"""
@@ -74,7 +83,7 @@ class ConfigurationForm(forms.Form):
                       'hyphens.  Total length must be 63 characters or less.'),
         validators=[
             validators.RegexValidator(
-                r'^[a-zA-Z0-9]([-a-zA-Z0-9]{,61}[a-zA-Z0-9])?$',
+                HOSTNAME_REGEX,
                 ugettext_lazy('Invalid hostname'))])
 
     domainname = TrimmedCharField(
@@ -90,8 +99,9 @@ class ConfigurationForm(forms.Form):
         required=False,
         validators=[
             validators.RegexValidator(
-                r'^[a-zA-Z0-9]([-a-zA-Z0-9.]*[a-zA-Z0-9])?$',
-                ugettext_lazy('Invalid domain name'))])
+                r'^[a-zA-Z0-9]([-a-zA-Z0-9.]{,251}[a-zA-Z0-9])?$',
+                ugettext_lazy('Invalid domain name')),
+            domain_labelvalidator])
 
 
 def init():

plinth/modules/config/tests/test_config.py

@@ -47,12 +47,15 @@ class TestConfig(unittest.TestCase):
 
     def test_domainname_field(self):
         """Test that domainname field accepts only valid domainnames."""
+
         valid_domainnames = [
             '', 'a', '0a', 'a0', 'AAA', '00', '0-0', 'example-hostname',
             'example', 'example.org', 'a.b.c.d', 'a-0.b-0.c-0',
-            '012345678901234567890123456789012345678901234567890123456789012']
+            '012345678901234567890123456789012345678901234567890123456789012',
+            ((('x' * 63) + '.') * 3) + 'x' * 61]
         invalid_domainnames = [
-            '-', '-a', 'a-', '.a', 'a.', '?', 'a?a']
+            '-', '-a', 'a-', '.a', 'a.', '?', 'a?a', 'a..a', 'a.-a', '.',
+            ((('x' * 63) + '.') * 3) + 'x' * 62, 'x' * 64]
 
         for domainname in valid_domainnames:
             form = ConfigurationForm({'hostname': 'example',