Get subnets logic

get-subnets.py

@@ -0,0 +1,66 @@
+#!/usr/bin/python3.10
+
+import ipaddress
+import urllib.request
+
+BGP_TOOLS_URL = 'https://bgp.tools/table.txt'
+USER_AGENT = 'itdog.info - hi@itdog.info'
+AS_FILE = 'AS.lst'
+IPv4_DIR = 'Subnets/IPv4'
+IPv6_DIR = 'Subnets/IPv6'
+
+AS_META = '32934'
+AS_TWITTER = '13414'
+META = 'Meta.lst'
+TWITTER = 'Twitter.lst'
+
+subnet_list = []
+
+def subnet_summarization(subnet_list):
+    subnets = [ipaddress.ip_network(subnet) for subnet in subnet_list]
+    return list(ipaddress.collapse_addresses(subnets))
+
+def process_subnets(subnet_list, target_as):
+    ipv4_subnets = []
+    ipv6_subnets = []
+
+    for subnet_str, as_number in subnet_list:
+        try:
+            subnet = ipaddress.ip_network(subnet_str)
+            if as_number == target_as:
+                if subnet.version == 4:
+                    ipv4_subnets.append(subnet_str)
+                elif subnet.version == 6:
+                    ipv6_subnets.append(subnet_str)
+        except ValueError:
+            print(f"Invalid subnet: {subnet_str}")
+            sys.exit(1)
+
+    ipv4_merged = subnet_summarization(ipv4_subnets)
+    ipv6_merged = subnet_summarization(ipv6_subnets)
+
+    return ipv4_merged, ipv6_merged
+
+def write_subnets_to_file(subnets, filename):
+    with open(filename, 'w') as file:
+        for subnet in subnets:
+            file.write(f'{subnet}\n')
+
+if __name__ == '__main__':
+    request = urllib.request.Request(BGP_TOOLS_URL, headers={'User-Agent': USER_AGENT})
+    
+    with urllib.request.urlopen(request) as response:
+        for line in response:
+            decoded_line = line.decode('utf-8').strip()
+            subnet, as_number = decoded_line.split()
+            subnet_list.append((subnet, as_number))
+
+    # Meta
+    ipv4_merged_meta, ipv6_merged_meta = process_subnets(subnet_list, AS_META)
+    write_subnets_to_file(ipv4_merged_meta, f'{IPv4_DIR}/{META}')
+    write_subnets_to_file(ipv6_merged_meta, f'{IPv6_DIR}/{META}')
+
+    # Twitter
+    ipv4_merged_twitter, ipv6_merged_twitter = process_subnets(subnet_list, AS_TWITTER)
+    write_subnets_to_file(ipv4_merged_twitter, f'{IPv4_DIR}/{TWITTER}')
+    write_subnets_to_file(ipv6_merged_twitter, f'{IPv6_DIR}/{TWITTER}')