tools/generate-nl80211-fields.py

   1 #!/usr/bin/env python3
   2 # Parses the nl80211.h interface and generate appropriate enums and fields
   3 # (value_string) for packet-netlink-nl80211.c
   4 #
   5 # Copyright (c) 2017, Peter Wu <peter@lekensteyn.nl>
   6 # Copyright (c) 2018, Mikael Kanstrup <mikael.kanstrup@sony.com>
   7 #
   8 # Wireshark - Network traffic analyzer
   9 # By Gerald Combs <gerald@wireshark.org>
  10 # Copyright 1998 Gerald Combs
  11 #
  12 # SPDX-License-Identifier: GPL-2.0-or-later
  13 #
  14 #
  15 # To update the dissector source file, run this from the source directory:
  16 #
  17 #   python tools/generate-nl80211-fields.py --update
  18 #
  19
  20 import argparse
  21 import re
  22 import requests
  23 import sys
  24
  25 # Begin of comment, followed by the actual array definition
  26 HEADER = "/* Definitions from linux/nl80211.h {{{ */\n"
  27 FOOTER = "/* }}} */\n"
  28 # Enums to extract from the header file
  29 EXPORT_ENUMS = {
  30     # 'enum_name': ('field_name', field_type', 'field_blurb')
  31     'nl80211_commands': ('Command', 'FT_UINT8', '"Generic Netlink Command"'),
  32     'nl80211_attrs': (None, None, None),
  33     'nl80211_iftype': (None, None, None),
  34     'nl80211_sta_flags': (None, None, None),
  35     'nl80211_sta_p2p_ps_status': ('Attribute Value', 'FT_UINT8', None),
  36     'nl80211_he_gi': (None, None, None),
  37     'nl80211_he_ltf': (None, None, None),
  38     'nl80211_he_ru_alloc': (None, None, None),
  39     'nl80211_eht_gi': (None, None, None),
  40     'nl80211_eht_ru_alloc': (None, None, None),
  41     'nl80211_rate_info': (None, None, None),
  42     'nl80211_sta_bss_param': (None, None, None),
  43     'nl80211_sta_info': (None, None, None),
  44     'nl80211_tid_stats': (None, None, None),
  45     'nl80211_txq_stats': (None, None, None),
  46     'nl80211_mpath_flags': (None, None, None),
  47     'nl80211_mpath_info': (None, None, None),
  48     'nl80211_band_iftype_attr': (None, None, None),
  49     'nl80211_band_attr': (None, None, None),
  50     'nl80211_wmm_rule': (None, None, None),
  51     'nl80211_frequency_attr': (None, None, None),
  52     'nl80211_bitrate_attr': (None, None, None),
  53     'nl80211_reg_initiator': ('Attribute Value', 'FT_UINT8', None),
  54     'nl80211_reg_type': ('Attribute Value', 'FT_UINT8', None),
  55     'nl80211_reg_rule_attr': (None, None, None),
  56     'nl80211_sched_scan_match_attr': (None, None, None),
  57     'nl80211_reg_rule_flags': (None, None, None),
  58     'nl80211_dfs_regions': ('Attribute Value', 'FT_UINT8', None),
  59     'nl80211_user_reg_hint_type': ('Attribute Value', 'FT_UINT32', None),
  60     'nl80211_survey_info': (None, None, None),
  61     'nl80211_mntr_flags': (None, None, None),
  62     'nl80211_mesh_power_mode': ('Attribute Value', 'FT_UINT32', None),
  63     'nl80211_meshconf_params': (None, None, None),
  64     'nl80211_mesh_setup_params': (None, None, None),
  65     'nl80211_txq_attr': (None, None, None),
  66     'nl80211_ac': (None, None, None),
  67     'nl80211_channel_type': ('Attribute Value', 'FT_UINT32', None),
  68     'nl80211_key_mode': (None, None, None),
  69     'nl80211_chan_width': ('Attribute Value', 'FT_UINT32', None),
  70     'nl80211_bss_scan_width': ('Attribute Value', 'FT_UINT32', None),
  71     'nl80211_bss_use_for': (None, None, None),
  72     'nl80211_bss_cannot_use_reasons': (None, None, None),
  73     'nl80211_bss': (None, None, None),
  74     'nl80211_bss_status': ('Attribute Value', 'FT_UINT32', None),
  75     'nl80211_auth_type': ('Attribute Value', 'FT_UINT32', None),
  76     'nl80211_key_type': ('Attribute Value', 'FT_UINT32', None),
  77     'nl80211_mfp': ('Attribute Value', 'FT_UINT32', None),
  78     'nl80211_wpa_versions': (None, None, None),
  79     'nl80211_key_default_types': (None, None, None),
  80     'nl80211_key_attributes': (None, None, None),
  81     'nl80211_tx_rate_attributes': (None, None, None),
  82     'nl80211_txrate_gi': (None, None, None),
  83     'nl80211_band': (None, None, None),
  84     'nl80211_ps_state': ('Attribute Value', 'FT_UINT32', None),
  85     'nl80211_attr_cqm': (None, None, None),
  86     'nl80211_cqm_rssi_threshold_event': (None, None, None),
  87     'nl80211_tx_power_setting': ('Attribute Value', 'FT_UINT32', None),
  88     'nl80211_tid_config': (None, None, None),
  89     'nl80211_tx_rate_setting': (None, None, None),
  90     'nl80211_tid_config_attr': (None, None, None),
  91     'nl80211_packet_pattern_attr': (None, None, None),
  92     'nl80211_wowlan_triggers': (None, None, None),
  93     'nl80211_wowlan_tcp_attrs': (None, None, None),
  94     'nl80211_attr_coalesce_rule': (None, None, None),
  95     'nl80211_coalesce_condition': (None, None, None),
  96     'nl80211_iface_limit_attrs': (None, None, None),
  97     'nl80211_if_combination_attrs': (None, None, None),
  98     'nl80211_plink_state': ('Attribute Value', 'FT_UINT8', None),
  99     'nl80211_plink_action': ('Attribute Value', 'FT_UINT8', None),
 100     'nl80211_rekey_data': (None, None, None),
 101     'nl80211_hidden_ssid': (None, None, None),
 102     'nl80211_sta_wme_attr': (None, None, None),
 103     'nl80211_pmksa_candidate_attr': (None, None, None),
 104     'nl80211_tdls_operation': ('Attribute Value', 'FT_UINT8', None),
 105     'nl80211_ap_sme_features': (None, None, None),
 106     'nl80211_feature_flags': (None, None, None),
 107     'nl80211_ext_feature_index': (None, None, None),
 108     'nl80211_probe_resp_offload_support_attr': (None, None, None),
 109     'nl80211_connect_failed_reason': ('Attribute Value', 'FT_UINT32', None),
 110     'nl80211_timeout_reason': ('Attribute Value', 'FT_UINT32', None),
 111     'nl80211_scan_flags': (None, None, None),
 112     'nl80211_acl_policy': ('Attribute Value', 'FT_UINT32', None),
 113     'nl80211_smps_mode': ('Attribute Value', 'FT_UINT8', None),
 114     'nl80211_radar_event': ('Attribute Value', 'FT_UINT32', None),
 115     'nl80211_dfs_state': (None, None, None),
 116     'nl80211_protocol_features': (None, None, None),
 117     'nl80211_crit_proto_id': ('Attribute Value', 'FT_UINT16', None),
 118     'nl80211_rxmgmt_flags': (None, None, None),
 119     'nl80211_tdls_peer_capability': (None, None, None),
 120     'nl80211_sched_scan_plan': (None, None, None),
 121     'nl80211_bss_select_attr': (None, None, None),
 122     'nl80211_nan_function_type': (None, None, None),
 123     'nl80211_nan_publish_type': (None, None, None),
 124     'nl80211_nan_func_term_reason': (None, None, None),
 125     'nl80211_nan_func_attributes': (None, None, None),
 126     'nl80211_nan_srf_attributes': (None, None, None),
 127     'nl80211_nan_match_attributes': (None, None, None),
 128     'nl80211_external_auth_action': ('Attribute Value', 'FT_UINT32', None),
 129     'nl80211_ftm_responder_attributes': (None, None, None),
 130     'nl80211_ftm_responder_stats': (None, None, None),
 131     'nl80211_preamble': (None, None, None),
 132     'nl80211_peer_measurement_type': (None, None, None),
 133     'nl80211_peer_measurement_status': (None, None, None),
 134     'nl80211_peer_measurement_req': (None, None, None),
 135     'nl80211_peer_measurement_resp': (None, None, None),
 136     'nl80211_peer_measurement_peer_attrs': (None, None, None),
 137     'nl80211_peer_measurement_attrs': (None, None, None),
 138     'nl80211_peer_measurement_ftm_capa': (None, None, None),
 139     'nl80211_peer_measurement_ftm_req': (None, None, None),
 140     'nl80211_peer_measurement_ftm_failure_reasons': (None, None, None),
 141     'nl80211_peer_measurement_ftm_resp': (None, None, None),
 142     'nl80211_obss_pd_attributes': (None, None, None),
 143     'nl80211_bss_color_attributes': (None, None, None),
 144     'nl80211_iftype_akm_attributes': (None, None, None),
 145     'nl80211_fils_discovery_attributes': (None, None, None),
 146     'nl80211_unsol_bcast_probe_resp_attributes': (None, None, None),
 147     'nl80211_sae_pwe_mechanism': (None, None, None),
 148     'nl80211_sar_type': (None, None, None),
 149     'nl80211_sar_attrs': (None, None, None),
 150     'nl80211_sar_specs_attrs': (None, None, None),
 151     'nl80211_mbssid_config_attributes': (None, None, None),
 152     'nl80211_ap_settings_flags': (None, None, None),
 153     'nl80211_wiphy_radio_attrs': (None, None, None),
 154     'nl80211_wiphy_radio_freq_range': (None, None, None),
 155 }
 156 # File to be patched
 157 SOURCE_FILE = "epan/dissectors/packet-netlink-nl80211.c"
 158 # URL where the latest version can be found
 159 URL = "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/plain/include/uapi/linux/nl80211.h"
 160
 161 def make_enum(name, values, expressions, indent):
 162     code = 'enum ws_%s {\n' % name
 163     for value, expression in zip(values, expressions):
 164         if expression and 'NL80211' in expression:
 165             expression = 'WS_%s' % expression
 166         if expression:
 167             code += '%sWS_%s = %s,\n' % (indent, value, expression)
 168         else:
 169             code += '%sWS_%s,\n' % (indent, value)
 170
 171     code += '};\n'
 172     return code
 173
 174 def make_value_string(name, values, indent,):
 175     code = 'static const value_string ws_%s_vals[] = {\n' % name
 176     align = 40
 177     for value in values:
 178         code += indent + ('{ WS_%s,' % value).ljust(align - 1) + ' '
 179         code += '"%s" },\n' % value
 180     code += '%s{ 0, NULL }\n' % indent
 181     code += '};\n'
 182     code += 'static value_string_ext ws_%s_vals_ext =' % name
 183     code += ' VALUE_STRING_EXT_INIT(ws_%s_vals);\n' % name
 184     return code
 185
 186 def remove_prefix(prefix, text):
 187     if text.startswith(prefix):
 188         return text[len(prefix):]
 189     return text
 190
 191 def make_hf_defs(name, indent):
 192     code = 'static int hf_%s;' % name
 193     return code
 194
 195 def make_hf(name, indent):
 196     (field_name, field_type, field_blurb) = EXPORT_ENUMS.get(name)
 197     field_abbrev = name
 198
 199     # Fill in default values
 200     if not field_name:
 201         field_name = 'Attribute Type'
 202     if not field_type:
 203         field_type = 'FT_UINT16'
 204     if not field_blurb:
 205         field_blurb = 'NULL'
 206
 207     # Special treatment of already existing field names
 208     rename_fields = {
 209         'nl80211_attrs': 'nl80211_attr_type',
 210         'nl80211_commands': 'nl80211_cmd'
 211     }
 212     if rename_fields.get(name):
 213         field_abbrev = rename_fields[name]
 214     field_abbrev = remove_prefix('nl80211_', field_abbrev)
 215
 216     code = indent + indent + '{ &hf_%s,\n' % name
 217     code += indent*3 + '{ "%s", "nl80211.%s",\n' % (field_name, field_abbrev)
 218     code += indent*3 + '  %s, BASE_DEC | BASE_EXT_STRING,\n' % (field_type)
 219     code += indent*3 + '  VALS_EXT_PTR(&ws_%s_vals_ext), 0x00,\n' % (name)
 220     code += indent*3 + '  %s, HFILL },\n' % (field_blurb)
 221     code += indent + indent + '},'
 222     return code
 223
 224 def make_ett_defs(name, indent):
 225     code = 'static int ett_%s;' % name
 226     return code
 227
 228 def make_ett(name, indent):
 229     code = indent + indent + '&ett_%s,' % name
 230     return code
 231
 232 class EnumStore(object):
 233     __RE_ENUM_VALUE = re.compile(
 234         r'\s+?(?P<value>\w+)(?:\ /\*.*?\*\/)?(?:\s*=\s*(?P<expression>.*?))?(?:\s*,|$)',
 235         re.MULTILINE | re.DOTALL)
 236
 237     def __init__(self, name, values):
 238         self.name = name
 239         self.values = []
 240         self.expressions = []
 241         self.active = True
 242         self.parse_values(values)
 243
 244
 245     def parse_values(self, values):
 246         for m in self.__RE_ENUM_VALUE.finditer(values):
 247             value, expression = m.groups()
 248             if value.startswith('NUM_'):
 249                 break
 250             if value.endswith('_AFTER_LAST'):
 251                 break
 252             if value.endswith('_LAST'):
 253                 break
 254             if value.startswith('__') and value.endswith('_NUM'):
 255                 break
 256             if expression and expression in self.values:
 257                 # Skip aliases
 258                 continue
 259             self.values.append(value)
 260             self.expressions.append(expression)
 261
 262     def finish(self):
 263         return self.name, self.values, self.expressions
 264
 265 RE_ENUM = re.compile(
 266     r'enum\s+?(?P<enum>\w+)\s+?\{(?P<values>.*?)\}\;',
 267     re.MULTILINE | re.DOTALL)
 268 RE_COMMENT = re.compile(r'/\*.*?\*/', re.MULTILINE | re.DOTALL)
 269
 270 def parse_header(content):
 271     # Strip comments
 272     content = re.sub(RE_COMMENT, '', content)
 273
 274     enums = []
 275     for m in RE_ENUM.finditer(content):
 276         enum = m.group('enum')
 277         values = m.group('values')
 278         if enum in EXPORT_ENUMS:
 279             enums.append(EnumStore(enum, values).finish())
 280
 281     return enums
 282
 283 def parse_source():
 284     """
 285     Reads the source file and tries to split it in the parts before, inside and
 286     after the block.
 287     """
 288     begin, block, end = '', '', ''
 289     parts = []
 290     # Stages: 1 (before block), 2 (in block, skip), 3 (after block)
 291     stage = 1
 292     with open(SOURCE_FILE) as f:
 293         for line in f:
 294             if line == FOOTER and stage == 2:
 295                 stage = 3   # End of block
 296             if stage == 1:
 297                 begin += line
 298             elif stage == 2:
 299                 block += line
 300             elif stage == 3:
 301                 end += line
 302             if line == HEADER and stage == 1:
 303                 stage = 2   # Begin of block
 304             if line == HEADER and stage == 3:
 305                 stage = 2   # Begin of next code block
 306                 parts.append((begin, block, end))
 307                 begin, block, end = '', '', ''
 308
 309     parts.append((begin, block, end))
 310     if stage != 3 or len(parts) != 3:
 311         raise RuntimeError("Could not parse file (in stage %d) (parts %d)" % (stage, len(parts)))
 312     return parts
 313
 314 parser = argparse.ArgumentParser()
 315 parser.add_argument("--update", action="store_true",
 316         help="Update %s as needed instead of writing to stdout" % SOURCE_FILE)
 317 parser.add_argument("--indent", default=" " * 4,
 318         help="indentation (use \\t for tabs, default 4 spaces)")
 319 parser.add_argument("header_file", nargs="?", default=URL,
 320         help="nl80211.h header file (use - for stdin or a HTTP(S) URL, "
 321              "default %(default)s)")
 322
 323 def main():
 324     args = parser.parse_args()
 325
 326     indent = args.indent.replace("\\t", "\t")
 327
 328     if any(args.header_file.startswith(proto) for proto in ('http:', 'https')):
 329         r = requests.get(args.header_file)
 330         r.raise_for_status()
 331         enums = parse_header(r.text)
 332     elif args.header_file == "-":
 333         enums = parse_header(sys.stdin.read())
 334     else:
 335         with open(args.header_file) as f:
 336             enums = parse_header(f.read())
 337
 338     assert len(enums) == len(EXPORT_ENUMS), \
 339             "Could not parse data, found %d/%d results" % \
 340             (len(enums), len(EXPORT_ENUMS))
 341
 342     code_enums, code_vals, code_hf_defs, code_ett_defs, code_hf, code_ett = '', '', '', '', '', ''
 343     for enum_name, enum_values, expressions in enums:
 344         code_enums += make_enum(enum_name, enum_values, expressions, indent) + '\n'
 345         code_vals += make_value_string(enum_name, enum_values, indent) + '\n'
 346         code_hf_defs += make_hf_defs(enum_name, indent) + '\n'
 347         code_ett_defs += make_ett_defs(enum_name, indent) + '\n'
 348         code_hf += make_hf(enum_name, indent) + '\n'
 349         code_ett += make_ett(enum_name, indent) + '\n'
 350
 351     code_top = code_enums + code_vals + code_hf_defs + '\n' + code_ett_defs
 352     code_top = code_top.rstrip("\n") + "\n"
 353
 354     code = [code_top, code_hf, code_ett]
 355
 356     update = False
 357     if args.update:
 358         parts = parse_source()
 359
 360         # Check if file needs update
 361         for (begin, old_code, end), new_code in zip(parts, code):
 362             if old_code != new_code:
 363                 update = True
 364                 break
 365         if not update:
 366             print("File is up-to-date")
 367             return
 368         # Update file
 369         with open(SOURCE_FILE, "w") as f:
 370             for (begin, old_code, end), new_code in zip(parts, code):
 371                 f.write(begin)
 372                 f.write(new_code)
 373                 f.write(end)
 374         print("Updated %s" % SOURCE_FILE)
 375     else:
 376         for new_code in code:
 377             print(new_code)
 378
 379 if __name__ == '__main__':
 380     main()
 381
 382 #
 383 # Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 384 #
 385 # Local variables:
 386 # c-basic-offset: 4
 387 # tab-width: 8
 388 # indent-tabs-mode: nil
 389 # End:
 390 #
 391 # vi: set shiftwidth=4 tabstop=8 expandtab:
 392 # :indentSize=4:tabSize=8:noTabs=true:
 393 #