Fixes #43: Introduce toggle to enforce unique IP space per VRF

docs/configuration/optional-settings.md

@@ -47,9 +47,17 @@ In order to send email, NetBox needs an email server configured. The following i
 
 ---
 
+# ENFORCE_GLOBAL_UNIQUE
+
+Default: False
+
+Enforcement of unique IP space can be toggled on a per-VRF basis. To enforce unique IP space within the global table (all prefixes and IP addresses not assigned to a VRF), set `ENFORCE_GLOBAL_UNIQUE` to True.
+
+---
+
 ## LOGIN_REQUIRED
 
-Default: False,
+Default: False
 
 Setting this to True will permit only authenticated users to access any part of NetBox. By default, anonymous users are permitted to access most data in NetBox (excluding secrets) but not make any changes.
 

netbox/ipam/api/serializers.py

@@ -12,7 +12,7 @@ class VRFSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = VRF
-        fields = ['id', 'name', 'rd', 'description']
+        fields = ['id', 'name', 'rd', 'enforce_unique', 'description']
 
 
 class VRFNestedSerializer(VRFSerializer):

netbox/ipam/forms.py

@@ -25,7 +25,7 @@ class VRFForm(forms.ModelForm, BootstrapMixin):
 
     class Meta:
         model = VRF
-        fields = ['name', 'rd', 'description']
+        fields = ['name', 'rd', 'enforce_unique', 'description']
         labels = {
             'rd': "RD",
         }
@@ -38,7 +38,7 @@ class VRFFromCSVForm(forms.ModelForm):
 
     class Meta:
         model = VRF
-        fields = ['name', 'rd', 'description']
+        fields = ['name', 'rd', 'enforce_unique', 'description']
 
 
 class VRFImportForm(BulkImportForm, BootstrapMixin):

netbox/ipam/migrations/0002_vrf_add_enforce_unique.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.7 on 2016-07-14 19:34
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('ipam', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='vrf',
+            name='enforce_unique',
+            field=models.BooleanField(default=True, help_text=b'Prevent duplicate prefixes/IP addresses within this VRF', verbose_name=b'Enforce unique space'),
+        ),
+    ]

netbox/ipam/models.py

@@ -1,5 +1,6 @@
 from netaddr import IPNetwork, cidr_merge
 
+from django.conf import settings
 from django.core.exceptions import ValidationError
 from django.core.urlresolvers import reverse
 from django.core.validators import MaxValueValidator, MinValueValidator
@@ -45,6 +46,8 @@ class VRF(CreatedUpdatedModel):
     """
     name = models.CharField(max_length=50)
     rd = models.CharField(max_length=21, unique=True, verbose_name='Route distinguisher')
+    enforce_unique = models.BooleanField(default=True, verbose_name='Enforce unique space',
+                                         help_text="Prevent duplicate prefixes/IP addresses within this VRF")
     description = models.CharField(max_length=100, blank=True)
 
     class Meta:
@@ -309,6 +312,21 @@ class IPAddress(CreatedUpdatedModel):
     def get_absolute_url(self):
         return reverse('ipam:ipaddress', args=[self.pk])
 
+    def clean(self):
+
+        # Enforce unique IP space if applicable
+        if self.vrf and self.vrf.enforce_unique:
+            duplicate_ips = IPAddress.objects.filter(vrf=self.vrf, address__net_host=str(self.address.ip))\
+                .exclude(pk=self.pk)
+            if duplicate_ips:
+                raise ValidationError("Duplicate IP address found in VRF {}: {}".format(self.vrf,
+                                                                                        duplicate_ips.first()))
+        elif not self.vrf and settings.ENFORCE_GLOBAL_UNIQUE:
+            duplicate_ips = IPAddress.objects.filter(vrf=None, address__net_host=str(self.address.ip))\
+                .exclude(pk=self.pk)
+            if duplicate_ips:
+                raise ValidationError("Duplicate IP address found in global table: {}".format(duplicate_ips.first()))
+
     def save(self, *args, **kwargs):
         if self.address:
             # Infer address family from IPAddress object

netbox/netbox/configuration.example.py

@@ -82,3 +82,7 @@ BANNER_BOTTOM = ''
 # When determining the primary IP address for a device, IPv6 is preferred over IPv4 by default. Set this to True to
 # prefer IPv4 instead.
 PREFER_IPV4 = False
+
+# Enforcement of unique IP space can be toggled on a per-VRF basis. To enforce unique IP space within the global table
+# (all prefixes and IP addresses not assigned to a VRF), set ENFORCE_GLOBAL_UNIQUE to True.
+ENFORCE_GLOBAL_UNIQUE = False

netbox/netbox/settings.py

@@ -41,6 +41,7 @@ SHORT_DATETIME_FORMAT = getattr(configuration, 'SHORT_DATETIME_FORMAT', 'Y-m-d H
 BANNER_TOP = getattr(configuration, 'BANNER_TOP', False)
 BANNER_BOTTOM = getattr(configuration, 'BANNER_BOTTOM', False)
 PREFER_IPV4 = getattr(configuration, 'PREFER_IPV4', False)
+ENFORCE_GLOBAL_UNIQUE = getattr(configuration, 'ENFORCE_GLOBAL_UNIQUE', False)
 CSRF_TRUSTED_ORIGINS = ALLOWED_HOSTS
 
 # Attempt to import LDAP configuration if it has been defined

netbox/templates/ipam/vrf.html

@@ -31,6 +31,16 @@
                     <td>{{ vrf.rd }}</td>
                 </tr>
                 <tr>
+                    <td>Enforce Uniqueness</td>
+                    <td>
+                        {% if vrf.enforce_unique %}
+                            <i class="glyphicon glyphicon-ok text-success" title="Yes"></i>
+                        {% else %}
+                            <i class="glyphicon glyphicon-remove text-danger" title="No"></i>
+                        {% endif %}
+                    </td>
+                </tr>
+                <tr>
                     <td>Description</td>
                     <td>
                         {% if vrf.description  %}

netbox/templates/ipam/vrf_import.html

@@ -39,6 +39,11 @@
 					<td>65000:123456</td>
 				</tr>
 				<tr>
+					<td>Enforce uniqueness</td>
+					<td>Prevent duplicate prefixes/IP addresses</td>
+					<td>True</td>
+				</tr>
+				<tr>
 					<td>Description</td>
 					<td>Short description (optional)</td>
 					<td>Native VRF for customer ABC</td>
@@ -46,7 +51,7 @@
 			</tbody>
 		</table>
 		<h4>Example</h4>
-		<pre>Customer_ABC,65000:123456,Native VRF for customer ABC</pre>
+		<pre>Customer_ABC,65000:123456,True,Native VRF for customer ABC</pre>
 	</div>
 </div>
 {% endblock %}