tools/make-iana-ip.py

   1 #!/usr/bin/env python3
   2 #
   3 # Wireshark - Network traffic analyzer
   4 # By Gerald Combs <gerald@wireshark.org>
   5 # Copyright 1998 Gerald Combs
   6 #
   7 # SPDX-License-Identifier: GPL-2.0-or-later
   8 '''Update the IANA IP registry file.
   9
  10 Make-iana-ip creates a file containing information about IPv4/IPv6 allocation blocks.
  11 '''
  12
  13 import csv
  14 import io
  15 import ipaddress
  16 import os
  17 import re
  18 import sys
  19 import urllib.request, urllib.error, urllib.parse
  20
  21 def exit_msg(msg=None, status=1):
  22     if msg is not None:
  23         sys.stderr.write(msg + '\n\n')
  24     sys.stderr.write(__doc__ + '\n')
  25     sys.exit(status)
  26
  27 def open_url(url):
  28     '''Open a URL.
  29     Returns a tuple containing the body and response dict. The body is a
  30     str in Python 3 and bytes in Python 2 in order to be compatible with
  31     csv.reader.
  32     '''
  33
  34     if len(sys.argv) > 1:
  35         url_path = os.path.join(sys.argv[1], url[1])
  36         url_fd = open(url_path)
  37         body = url_fd.read()
  38         url_fd.close()
  39     else:
  40         url_path = '/'.join(url)
  41
  42         req_headers = { 'User-Agent': 'Wireshark iana-ip' }
  43         try:
  44             req = urllib.request.Request(url_path, headers=req_headers)
  45             response = urllib.request.urlopen(req)
  46             body = response.read().decode('UTF-8', 'replace')
  47         except Exception:
  48             exit_msg('Error opening ' + url_path)
  49
  50     return body
  51
  52 class IPv4SpecialBlock(ipaddress.IPv4Network):
  53     @staticmethod
  54     def ip_get_subnet_mask(bits):
  55         masks = (
  56             0x00000000,
  57             0x80000000, 0xc0000000, 0xe0000000, 0xf0000000,
  58             0xf8000000, 0xfc000000, 0xfe000000, 0xff000000,
  59             0xff800000, 0xffc00000, 0xffe00000, 0xfff00000,
  60             0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000,
  61             0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000,
  62             0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00,
  63             0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0,
  64             0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff)
  65         if bits > 32:
  66             ValueError("Expected bit mask less or equal to 32")
  67         return masks[bits]
  68
  69     def __str__(self):
  70         addr = self.network_address
  71         mask = self.prefixlen
  72         line = '{{ .ipv4 = {{ {:#x}, {:#010x} }} }}'.format(addr, self.ip_get_subnet_mask(mask))
  73         return line
  74
  75 class IPv6SpecialBlock(ipaddress.IPv6Network):
  76     @staticmethod
  77     def addr_c_array(byte_array):
  78         if len(byte_array) != 16:
  79             raise ValueError("Expected byte array of length 16")
  80         c_array = ", ".join(f"0x{byte:02x}" for byte in byte_array)
  81         return f"{{ {c_array} }}"
  82
  83     def __str__(self):
  84         addr = self.network_address.packed
  85         mask = self.prefixlen
  86         line = '{{ .ipv6 = {{ {}, {} }} }}'.format(self.addr_c_array(addr), mask)
  87         return line
  88
  89 class IPRegistry(list):
  90     @staticmethod
  91     def true_or_false(val):
  92         if val == 'True':
  93             return '1'
  94         elif val == 'False':
  95             return '0'
  96         else:
  97             return '-1'
  98
  99     def append(self, row):
 100         ip, name, _, _, termin_date, source, destination, forward, glob, reserved = row
 101         if termin_date[0].isdigit():
 102             # skip allocations that have expired
 103             return
 104         name = re.sub(r'\[.*\]', '', name)
 105         name = '"' + name.replace('"', '\\"') + '"'
 106         source = self.true_or_false(source)
 107         destination = self.true_or_false(destination)
 108         forward = self.true_or_false(forward)
 109         glob = self.true_or_false(glob)
 110         reserved = self.true_or_false(reserved)
 111         super().append([ip, name, source, destination, forward, glob, reserved])
 112
 113 class IPv4Registry(IPRegistry):
 114     @staticmethod
 115     def ipv4_addr_and_mask(s):
 116         ip = IPv4SpecialBlock(s)
 117         return ip
 118
 119     def append(self, row):
 120         # some lines contain multiple (comma separated) blocks
 121         ip_list = row[0].split(',')
 122         for s in ip_list:
 123             # remove annotations like "1.1.1.1 [2]"
 124             ip_str = s.split()[0]
 125             row = [self.ipv4_addr_and_mask(ip_str)] + row[1:]
 126             super().append(row)
 127
 128     def fill(self):
 129         self.sort()
 130         fill_data = '_U_ static const struct ws_iana_ip_special_block __ipv4_special_block[] = {\n'
 131         for row in self:
 132             line = '    {{ 4, {}, {}, {}, {}, {}, {}, {} }},\n'.format(*row)
 133             fill_data += line
 134         fill_data += '};\n'
 135         return fill_data
 136
 137 class IPv6Registry(IPRegistry):
 138     @staticmethod
 139     def ipv6_addr_and_mask(s):
 140         ip_str = s.split()[0]
 141         ip = IPv6SpecialBlock(ip_str)
 142         return ip
 143
 144     def append(self, row):
 145         # remove annotations like "1.1.1.1 [2]"
 146         ip_str = row[0].split()[0]
 147         row = [self.ipv6_addr_and_mask(ip_str)] + row[1:]
 148         super().append(row)
 149
 150     def fill(self):
 151         self.sort()
 152         fill_data = '// GCC bug?\n'
 153         fill_data += 'DIAG_OFF(missing-braces)\n'
 154         fill_data += '_U_ static const struct ws_iana_ip_special_block __ipv6_special_block[] = {\n'
 155         for row in self:
 156             line = \
 157 '''    {{ 6, {},
 158             {}, {}, {}, {}, {}, {} }},\n'''.format(*row)
 159             fill_data += line
 160         fill_data += '};\n'
 161         fill_data += 'DIAG_ON(missing-braces)\n'
 162         return fill_data
 163
 164 IANA_URLS = {
 165     'IPv4':   { 'url': ["https://www.iana.org/assignments/iana-ipv4-special-registry", "iana-ipv4-special-registry-1.csv"], 'min_entries': 2 },
 166     'IPv6':   { 'url': ["https://www.iana.org/assignments/iana-ipv6-special-registry", "iana-ipv6-special-registry-1.csv"], 'min_entries': 2 },
 167 }
 168
 169 def dump_registry(db, reg):
 170     db_url = IANA_URLS[db]['url']
 171     print('Loading {} data from {}'.format(db, db_url))
 172     body = open_url(db_url)
 173     iana_csv = csv.reader(body.splitlines())
 174
 175     # Pop the title row.
 176     next(iana_csv)
 177     for iana_row in iana_csv:
 178         # Address Block,Name,RFC,Allocation Date,Termination Date,Source,Destination,Forwardable,Globally Reachable,Reserved-by-Protocol
 179         # ::1/128,Loopback Address,[RFC4291],2006-02,N/A,False,False,False,False,True
 180         reg.append(iana_row)
 181
 182     if len(reg) < IANA_URLS[db]['min_entries']:
 183         exit_msg("Too few {} entries. Got {}, wanted {}".format(db, len(reg), IANA_URLS[db]['min_entries']))
 184
 185     return reg.fill()
 186
 187 def main():
 188     iana_path = os.path.join(os.path.dirname(__file__), '..', 'epan', 'iana-ip-data.c')
 189
 190     iana_data = '''\
 191 /*
 192  * This file was generated by running ./tools/make-iana-ip.py.
 193  *
 194  * SPDX-License-Identifier: GPL-2.0-or-later
 195  */
 196
 197 #include "iana-ip.h"
 198
 199 '''
 200
 201     iana_data += dump_registry('IPv4', IPv4Registry())
 202     iana_data += '\n'
 203     iana_data += dump_registry('IPv6', IPv6Registry())
 204
 205     try:
 206         with io.open(iana_path, 'w', encoding='UTF-8') as iana_f:
 207             iana_f.write(iana_data)
 208     except:
 209         exit_msg("Couldn't open \"{}\" file for writing".format(iana_path))
 210
 211 if __name__ == '__main__':
 212     main()