#!/usr/bin/env python3 # create the enterprises.c file from # https://www.iana.org/assignments/enterprise-numbers/enterprise-numbers # or an offline copy # # Copyright 2022 by Moshe Kaplan # Based on make-sminmpec.pl by Gerald Combs # # Wireshark - Network traffic analyzer # By Gerald Combs # Copyright 2004 Gerald Combs # # SPDX-License-Identifier: GPL-2.0-or-later import os import argparse import re import urllib.request ENTERPRISES_CFILE = os.path.join('epan', 'enterprises.c') ENTERPRISE_NUMBERS_URL = "https://www.iana.org/assignments/enterprise-numbers/enterprise-numbers" DECIMAL_PATTERN = r"^(\d+)" # up to three spaces because of formatting errors in the source ORGANIZATION_PATTERN = r"^ ?(\S.*)" FORMERLY_PATTERN = r" \(((formerly|previously) .*)\)" LOOKUP_FUNCTION = r""" const char* global_enterprises_lookup(uint32_t value) { if (value > table.max_idx) { return NULL; } else return table.values[value]; } """ DUMP_FUNCTION = r""" void global_enterprises_dump(FILE *fp) { for (size_t idx = 0; idx <= table.max_idx; idx++) { if (table.values[idx] != NULL) { fprintf(fp, "%zu\t%s\n", idx, table.values[idx]); } } } """ # This intermediate format is no longer written to a file - returned as string def generate_enterprise_entries(file_content): # We only care about the "Decimal" and "Organization", # not the contact or email org_lines = [] last_updated = "" end_seen = False for line in file_content.splitlines(): decimal_match = re.match(DECIMAL_PATTERN, line) if decimal_match: decimal = decimal_match.group(0) elif re.match(ORGANIZATION_PATTERN, line): organization = line.strip() if organization.lower() == "unassigned": continue organization = re.sub(FORMERLY_PATTERN, r"\t# \1", organization) org_lines += [decimal + "\t" + organization] elif "last updated" in line.lower(): last_updated = line elif "end of document" in line.lower(): end_seen = True if not end_seen: raise Exception('"End of Document" not found. Truncated source file?') last_updated_line = "/* " + last_updated + " */\n\n" output = "\n".join(org_lines) + "\n" return (output,last_updated_line) class CFile: def __init__(self, filename, last_updated_line): self.filename = filename self.f = open(filename, 'w') self.mappings = {} self.highest_num = 0 # Write file header self.f.write('/* ' + os.path.basename(self.filename) + '\n') self.f.write(' *\n') self.f.write(' * Wireshark - Network traffic analyzer\n') self.f.write(' * By Gerald Combs \n') self.f.write(' * Copyright 1998 Gerald Combs\n') self.f.write(' *\n') self.f.write(' * Do not edit - this file is automatically generated\n') self.f.write(' * SPDX-License-Identifier: GPL-2.0-or-later\n') self.f.write(' */\n\n') self.f.write(last_updated_line) # Include header files self.f.write('#include "config.h"\n\n') self.f.write('#include \n') self.f.write('#include "enterprises.h"\n') self.f.write('\n\n') def __del__(self): self.f.write('typedef struct\n') self.f.write('{\n') self.f.write(' uint32_t max_idx;\n') self.f.write(' const char* values[' + str(self.highest_num+1) + '];\n') self.f.write('} global_enterprises_table_t;\n\n') # Write static table self.f.write('static global_enterprises_table_t table =\n') self.f.write('{\n') # Largest index self.f.write(' ' + str(self.highest_num) + ',\n') self.f.write(' {\n') # Entries (read from dict) for n in range(0, self.highest_num+1): if n not in self.mappings: # There are some gaps, write a NULL entry so can lookup by index line = ' NULL' else: line = ' "' + self.mappings[n] + '"' # Add coma. if n < self.highest_num: line += ',' # Add number as aligned comment. line += ' '*(90-len(line)) + '// ' + str(n) self.f.write(line+'\n') # End of array self.f.write(' }\n') # End of struct self.f.write('};\n') print('Re-generated', self.filename) # Lookup function self.f.write(LOOKUP_FUNCTION) # Dump function self.f.write(DUMP_FUNCTION) # Add an individual mapping to the function def addMapping(self, num, name): # Handle some escapings name = name.replace('\\', '\\\\') name = name.replace('"', '""') # Record. self.mappings[num] = name self.highest_num = num if num>self.highest_num else self.highest_num def main(): parser = argparse.ArgumentParser(description="Create the {} file.".format(ENTERPRISES_CFILE)) parser.add_argument('--infile') parser.add_argument('outfile', nargs='?', default=ENTERPRISES_CFILE) parsed_args = parser.parse_args() # Read data from file or webpage if parsed_args.infile: with open(parsed_args.infile, encoding='utf-8') as fh: data = fh.read() else: with urllib.request.urlopen(ENTERPRISE_NUMBERS_URL) as f: if f.status != 200: raise Exception("request for " + ENTERPRISE_NUMBERS_URL + " failed with result code " + f.status) data = f.read().decode('utf-8') # Find bits we need and generate enterprise entries enterprises_content,last_updated_line = generate_enterprise_entries(data) # Now write to a C file the contents (which is faster than parsing the global file at runtime). c_file = CFile(parsed_args.outfile, last_updated_line) mapping_re = re.compile(r'^(\d+)\s+(.*)$') for line in enterprises_content.splitlines(): match = mapping_re.match(line) if match: num, name = match.group(1), match.group(2) # Strip any comments and/or trailing whitespace idx = name.find('#') if idx != -1: name = name[0:idx] name = name.rstrip() # Add c_file.addMapping(int(num), name) if __name__ == "__main__": main()