From 114c68ff0bbb685720d9ac20a0156ce492b6e576 Mon Sep 17 00:00:00 2001
From: Ben Burwood <ben.burwood@outlook.com>
Date: Thu, 14 Mar 2024 19:53:29 +0000
Subject: [PATCH] Add IpRange Model and Form with Validation

---
 NetworkMapper/ip/forms.py     |  6 +++++
 NetworkMapper/ip/models/ip.py | 47 +++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+)
 create mode 100644 NetworkMapper/ip/models/ip.py

diff --git a/NetworkMapper/ip/forms.py b/NetworkMapper/ip/forms.py
index 707b114..ed82da1 100644
--- a/NetworkMapper/ip/forms.py
+++ b/NetworkMapper/ip/forms.py
@@ -1,6 +1,12 @@
 from django import forms
 
 from .models import ClientDevice, VLAN, WifiNetwork
+from .models.ip import IpRange
+
+class IpRangeForm(forms.Form):
+    class Meta:
+        model = IpRange
+        fields = ["start_address", "end_address", "num_addresses", "description"]
 
 
 class VLANForm(forms.ModelForm):
diff --git a/NetworkMapper/ip/models/ip.py b/NetworkMapper/ip/models/ip.py
new file mode 100644
index 0000000..4da1a71
--- /dev/null
+++ b/NetworkMapper/ip/models/ip.py
@@ -0,0 +1,47 @@
+from django.core.exceptions import ValidationError
+from django.db import models
+
+
+class IpRange(models.Model):
+    start_address = models.GenericIPAddressField()
+    end_address = models.GenericIPAddressField()
+    num_addresses = models.PositiveIntegerField()
+    description = models.TextField(blank=True, null=True)
+
+    def clean(self):
+        super().clean()
+
+        if self.start_address > self.end_address:
+            raise ValidationError("Start Address must be Lower than End Address")
+
+        if self.start_address.protocol != self.end_address.protocol:
+            raise ValidationError("Start Address and End Address must be of the same IP Version")
+
+        for other_ip_range in IpRange.objects.exclude(pk=self.pk):
+            if self.check_overlap(other_ip_range):
+                raise ValidationError("IP Range overlaps with another IP Range : " + other_ip_range)
+
+    def check_overlap(self, other: "IpRange") -> bool:
+        """Check if the given IP Range overlaps with the current IP Range"""
+        if self.start_address <= other.start_address <= self.end_address:
+            return True
+        if self.start_address <= other.end_address <= self.end_address:
+            return True
+        if other.start_address <= self.start_address <= other.end_address:
+            return True
+        if other.start_address <= self.end_address <= other.end_address:
+            return True
+        return False
+
+    @staticmethod
+    def ipv4_to_numeric(ip):
+        octets = ip.split(".")
+
+        for octet in octets:
+            if not octet.isdigit() or not 0 <= int(octet) <= 255:
+                raise ValueError("Invalid IPv4 address format")
+
+        numeric_ip = 0
+        for i in range(4):
+            numeric_ip += int(octets[i]) * (256 ** (3 - i))
+        return numeric_ip