3 # This file parses an sfatables command and generates XML files that parameterize
4 # matches and targets. Each such XML file defines a rule. Rules are dropped in directories
5 # that represent 'chains.' SFA loads rules from various chains and invokes them at certain
6 # 'hook points.' For example, it invokes rules in the 'OUTGOING' chain before returning
7 # the output of 'get_resources.'
15 from optparse import OptionParser
16 from sfatables import commands
17 from sfatables.xmlextension import Xmlextension
18 from sfatables.globals import *
20 def load_commands(module, list):
23 for command_name in list:
24 command_module = __import__(".".join([module,command_name]),fromlist=[module])
25 command = getattr(command_module, command_name)
26 command_dict[command_name]=command()
30 def load_xml_extensions(module, ext_dir):
33 exts = glob.glob(ext_dir + os.path.sep + "*")
35 module = Xmlextension(ext)
36 # get the filename and get rid of the ".xml" extension
37 ext_name = os.path.extsep.join(os.path.splitext(os.path.basename(ext))[:-1])
38 ext_dict[ext_name]=module
43 def create_parser(command_dict):
44 parser = OptionParser(usage="sfatables [command] [chain] [match] [target]",
45 description='See "man sfatables" for more detail.')
47 for k in command_dict.keys():
48 command = command_dict[k]
49 for (short_option,long_option) in command.options:
50 parser.add_option(short_option,long_option,dest=command.type,action=command.action,const=k,help=command.help,metavar="CHAIN")
54 def create_parser_xml_ext(ext_dict):
55 parser = OptionParser(usage="sfatables [command] [chain] [match] [target]",
56 description='See "man sfatables" for more detail.')
58 for k in ext_dict.keys():
60 for arg in command.arguments:
61 parser.add_option('',"--"+arg['name'],dest=arg['name'],help=arg['help'],metavar=arg['target'])
66 def partition(sep, lst):
81 # sfatables <command> -- <match> -- <target>
82 pargs = partition('--', sys.argv[1:])
84 command_dict = load_commands("sfatables.commands",commands.all)
85 command_parser = create_parser(command_dict)
86 (options, args) = command_parser.parse_args(pargs[0])
87 setattr(options, 'args', args)
89 command = command_dict[options.command]
93 raise Exception("Must specify match for this command")
94 match_dict = load_xml_extensions("sfatables.matches",match_dir)
95 match_parser = create_parser_xml_ext(match_dict)
96 matches_str = ",".join(match_dict.keys())
97 match_parser.add_option('-m','--match',dest='name',help='Match name (one of %s)'%matches_str, metavar = 'MATCH')
98 match_parser.add_option('-n','--negate',dest='negate',help='Negate result',action='store_true')
99 (match_options, args) = match_parser.parse_args(pargs[1])
101 name = match_options.name
103 print "Must specify match name with -m"
105 if (match_dict.has_key(name)):
106 setattr(match_options, 'arguments', match_dict[name].arguments)
108 raise Exception('Match %s not found'%name)
113 if (command.targets):
115 raise Exception("Must specify a target for this command")
116 target_dict = load_xml_extensions("sfatables.targets",target_dir)
117 target_parser = create_parser_xml_ext(target_dict)
118 targets_str = ",".join(target_dict.keys())
119 target_parser.add_option('-j','--jump',dest='name',help='Target name (one of %s)'%targets_str, metavar = 'TARGET')
120 target_parser.add_option('-e','--element',dest='element',help='Element name', metavar = 'ELEMENT')
121 (target_options, args) = target_parser.parse_args(pargs[2])
123 name = target_options.name
125 print "Must specify target name with -j"
127 if (target_dict.has_key(name)):
128 setattr(target_options, 'arguments', target_dict[name].arguments)
130 raise Exception('Target %s not found'%name)
133 target_options = None
135 command(options, match_options, target_options)
137 if __name__=='__main__':