diff options
Diffstat (limited to '')
| -rw-r--r-- | bin/python/isc/policy.py.in | 728 |
1 files changed, 728 insertions, 0 deletions
diff --git a/bin/python/isc/policy.py.in b/bin/python/isc/policy.py.in new file mode 100644 index 0000000..f7829fa --- /dev/null +++ b/bin/python/isc/policy.py.in @@ -0,0 +1,728 @@ +############################################################################ +# Copyright (C) Internet Systems Consortium, Inc. ("ISC") +# +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, You can obtain one at http://mozilla.org/MPL/2.0/. +# +# See the COPYRIGHT file distributed with this work for additional +# information regarding copyright ownership. +############################################################################ + +import re +import ply.lex as lex +import ply.yacc as yacc +from string import * +from copy import copy + + +############################################################################ +# PolicyLex: a lexer for the policy file syntax. +############################################################################ +class PolicyLex: + reserved = ('POLICY', + 'ALGORITHM_POLICY', + 'ZONE', + 'ALGORITHM', + 'DIRECTORY', + 'KEYTTL', + 'KEY_SIZE', + 'ROLL_PERIOD', + 'PRE_PUBLISH', + 'POST_PUBLISH', + 'COVERAGE', + 'STANDBY', + 'NONE') + + tokens = reserved + ('DATESUFFIX', + 'KEYTYPE', + 'ALGNAME', + 'STR', + 'QSTRING', + 'NUMBER', + 'LBRACE', + 'RBRACE', + 'SEMI') + reserved_map = {} + + t_ignore = ' \t' + t_ignore_olcomment = r'(//|\#).*' + + t_LBRACE = r'\{' + t_RBRACE = r'\}' + t_SEMI = r';'; + + def t_newline(self, t): + r'\n+' + t.lexer.lineno += t.value.count("\n") + + def t_comment(self, t): + r'/\*(.|\n)*?\*/' + t.lexer.lineno += t.value.count('\n') + + def t_DATESUFFIX(self, t): + r'(?i)(?<=[0-9 \t])(y(?:ears|ear|ea|e)?|mo(?:nths|nth|nt|n)?|w(?:eeks|eek|ee|e)?|d(?:ays|ay|a)?|h(?:ours|our|ou|o)?|mi(?:nutes|nute|nut|nu|n)?|s(?:econds|econd|econ|eco|ec|e)?)\b' + t.value = re.match(r'(?i)(y|mo|w|d|h|mi|s)([a-z]*)', t.value).group(1).lower() + return t + + def t_KEYTYPE(self, t): + r'(?i)\b(KSK|ZSK)\b' + t.value = t.value.upper() + return t + + def t_ALGNAME(self, t): + r'(?i)\b(RSAMD5|DH|DSA|NSEC3DSA|ECC|RSASHA1|NSEC3RSASHA1|RSASHA256|RSASHA512|ECCGOST|ECDSAP256SHA256|ECDSAP384SHA384|ED25519|ED448)\b' + t.value = t.value.upper() + return t + + def t_STR(self, t): + r'[A-Za-z._-][\w._-]*' + t.type = self.reserved_map.get(t.value, "STR") + return t + + def t_QSTRING(self, t): + r'"([^"\n]|(\\"))*"' + t.type = self.reserved_map.get(t.value, "QSTRING") + t.value = t.value[1:-1] + return t + + def t_NUMBER(self, t): + r'\d+' + t.value = int(t.value) + return t + + def t_error(self, t): + print("Illegal character '%s'" % t.value[0]) + t.lexer.skip(1) + + def __init__(self, **kwargs): + if 'maketrans' in dir(str): + trans = str.maketrans('_', '-') + else: + trans = maketrans('_', '-') + for r in self.reserved: + self.reserved_map[r.lower().translate(trans)] = r + self.lexer = lex.lex(object=self, **kwargs) + + def test(self, text): + self.lexer.input(text) + while True: + t = self.lexer.token() + if not t: + break + print(t) + +############################################################################ +# Policy: this object holds a set of DNSSEC policy settings. +############################################################################ +class Policy: + is_zone = False + is_alg = False + is_constructed = False + ksk_rollperiod = None + zsk_rollperiod = None + ksk_prepublish = None + zsk_prepublish = None + ksk_postpublish = None + zsk_postpublish = None + ksk_keysize = None + zsk_keysize = None + ksk_standby = None + zsk_standby = None + keyttl = None + coverage = None + directory = None + valid_key_sz_per_algo = {'DSA': [512, 1024], + 'NSEC3DSA': [512, 1024], + 'RSAMD5': [512, 4096], + 'RSASHA1': [512, 4096], + 'NSEC3RSASHA1': [512, 4096], + 'RSASHA256': [512, 4096], + 'RSASHA512': [512, 4096], + 'ECCGOST': None, + 'ECDSAP256SHA256': None, + 'ECDSAP384SHA384': None, + 'ED25519': None, + 'ED448': None} + + def __init__(self, name=None, algorithm=None, parent=None): + self.name = name + self.algorithm = algorithm + self.parent = parent + pass + + def __repr__(self): + return ("%spolicy %s:\n" + "\tinherits %s\n" + "\tdirectory %s\n" + "\talgorithm %s\n" + "\tcoverage %s\n" + "\tksk_keysize %s\n" + "\tzsk_keysize %s\n" + "\tksk_rollperiod %s\n" + "\tzsk_rollperiod %s\n" + "\tksk_prepublish %s\n" + "\tksk_postpublish %s\n" + "\tzsk_prepublish %s\n" + "\tzsk_postpublish %s\n" + "\tksk_standby %s\n" + "\tzsk_standby %s\n" + "\tkeyttl %s\n" + % + ((self.is_constructed and 'constructed ' or \ + self.is_zone and 'zone ' or \ + self.is_alg and 'algorithm ' or ''), + self.name or 'UNKNOWN', + self.parent and self.parent.name or 'None', + self.directory and ('"' + str(self.directory) + '"') or 'None', + self.algorithm or 'None', + self.coverage and str(self.coverage) or 'None', + self.ksk_keysize and str(self.ksk_keysize) or 'None', + self.zsk_keysize and str(self.zsk_keysize) or 'None', + self.ksk_rollperiod and str(self.ksk_rollperiod) or 'None', + self.zsk_rollperiod and str(self.zsk_rollperiod) or 'None', + self.ksk_prepublish and str(self.ksk_prepublish) or 'None', + self.ksk_postpublish and str(self.ksk_postpublish) or 'None', + self.zsk_prepublish and str(self.zsk_prepublish) or 'None', + self.zsk_postpublish and str(self.zsk_postpublish) or 'None', + self.ksk_standby and str(self.ksk_standby) or 'None', + self.zsk_standby and str(self.zsk_standby) or 'None', + self.keyttl and str(self.keyttl) or 'None')) + + def __verify_size(self, key_size, size_range): + return (size_range[0] <= key_size <= size_range[1]) + + def get_name(self): + return self.name + + def constructed(self): + return self.is_constructed + + def validate(self): + """ Check if the values in the policy make sense + :return: True/False if the policy passes validation + """ + if self.ksk_rollperiod and \ + self.ksk_prepublish is not None and \ + self.ksk_prepublish > self.ksk_rollperiod: + print(self.ksk_rollperiod) + return (False, + ('KSK pre-publish period (%d) exceeds rollover period %d' + % (self.ksk_prepublish, self.ksk_rollperiod))) + + if self.ksk_rollperiod and \ + self.ksk_postpublish is not None and \ + self.ksk_postpublish > self.ksk_rollperiod: + return (False, + ('KSK post-publish period (%d) exceeds rollover period %d' + % (self.ksk_postpublish, self.ksk_rollperiod))) + + if self.zsk_rollperiod and \ + self.zsk_prepublish is not None and \ + self.zsk_prepublish >= self.zsk_rollperiod: + return (False, + ('ZSK pre-publish period (%d) exceeds rollover period %d' + % (self.zsk_prepublish, self.zsk_rollperiod))) + + if self.zsk_rollperiod and \ + self.zsk_postpublish is not None and \ + self.zsk_postpublish >= self.zsk_rollperiod: + return (False, + ('ZSK post-publish period (%d) exceeds rollover period %d' + % (self.zsk_postpublish, self.zsk_rollperiod))) + + if self.ksk_rollperiod and \ + self.ksk_prepublish and self.ksk_postpublish and \ + self.ksk_prepublish + self.ksk_postpublish >= self.ksk_rollperiod: + return (False, + (('KSK pre/post-publish periods (%d/%d) ' + + 'combined exceed rollover period %d') % + (self.ksk_prepublish, + self.ksk_postpublish, + self.ksk_rollperiod))) + + if self.zsk_rollperiod and \ + self.zsk_prepublish and self.zsk_postpublish and \ + self.zsk_prepublish + self.zsk_postpublish >= self.zsk_rollperiod: + return (False, + (('ZSK pre/post-publish periods (%d/%d) ' + + 'combined exceed rollover period %d') % + (self.zsk_prepublish, + self.zsk_postpublish, + self.zsk_rollperiod))) + + if self.algorithm is not None: + # Validate the key size + key_sz_range = self.valid_key_sz_per_algo.get(self.algorithm) + if key_sz_range is not None: + # Verify KSK + if not self.__verify_size(self.ksk_keysize, key_sz_range): + return False, 'KSK key size %d outside valid range %s' \ + % (self.ksk_keysize, key_sz_range) + + # Verify ZSK + if not self.__verify_size(self.zsk_keysize, key_sz_range): + return False, 'ZSK key size %d outside valid range %s' \ + % (self.zsk_keysize, key_sz_range) + + # Specific check for DSA keys + if self.algorithm in ['DSA', 'NSEC3DSA'] and \ + self.ksk_keysize % 64 != 0: + return False, \ + ('KSK key size %d not divisible by 64 ' + + 'as required for DSA') % self.ksk_keysize + + if self.algorithm in ['DSA', 'NSEC3DSA'] and \ + self.zsk_keysize % 64 != 0: + return False, \ + ('ZSK key size %d not divisible by 64 ' + + 'as required for DSA') % self.zsk_keysize + + if self.algorithm in ['ECCGOST', \ + 'ECDSAP256SHA256', \ + 'ECDSAP384SHA384', \ + 'ED25519', \ + 'ED448']: + self.ksk_keysize = None + self.zsk_keysize = None + + return True, '' + +############################################################################ +# dnssec_policy: +# This class reads a dnssec.policy file and creates a dictionary of +# DNSSEC policy rules from which a policy for a specific zone can +# be generated. +############################################################################ +class PolicyException(Exception): + pass + +class dnssec_policy: + alg_policy = {} + named_policy = {} + zone_policy = {} + current = None + filename = None + initial = True + + def __init__(self, filename=None, **kwargs): + self.plex = PolicyLex() + self.tokens = self.plex.tokens + if 'debug' not in kwargs: + kwargs['debug'] = False + if 'write_tables' not in kwargs: + kwargs['write_tables'] = False + self.parser = yacc.yacc(module=self, **kwargs) + + # set defaults + self.setup('''policy global { algorithm rsasha256; + key-size ksk 2048; + key-size zsk 2048; + roll-period ksk 0; + roll-period zsk 1y; + pre-publish ksk 1mo; + pre-publish zsk 1mo; + post-publish ksk 1mo; + post-publish zsk 1mo; + standby ksk 0; + standby zsk 0; + keyttl 1h; + coverage 6mo; }; + policy default { policy global; };''') + + p = Policy() + p.algorithm = None + p.is_alg = True + p.ksk_keysize = 2048; + p.zsk_keysize = 2048; + + # set default algorithm policies + # these need a lower default key size: + self.alg_policy['DSA'] = copy(p) + self.alg_policy['DSA'].algorithm = "DSA" + self.alg_policy['DSA'].name = "DSA" + self.alg_policy['DSA'].ksk_keysize = 1024; + + self.alg_policy['NSEC3DSA'] = copy(p) + self.alg_policy['NSEC3DSA'].algorithm = "NSEC3DSA" + self.alg_policy['NSEC3DSA'].name = "NSEC3DSA" + self.alg_policy['NSEC3DSA'].ksk_keysize = 1024; + + # these can use default settings + self.alg_policy['RSAMD5'] = copy(p) + self.alg_policy['RSAMD5'].algorithm = "RSAMD5" + self.alg_policy['RSAMD5'].name = "RSAMD5" + + self.alg_policy['RSASHA1'] = copy(p) + self.alg_policy['RSASHA1'].algorithm = "RSASHA1" + self.alg_policy['RSASHA1'].name = "RSASHA1" + + self.alg_policy['NSEC3RSASHA1'] = copy(p) + self.alg_policy['NSEC3RSASHA1'].algorithm = "NSEC3RSASHA1" + self.alg_policy['NSEC3RSASHA1'].name = "NSEC3RSASHA1" + + self.alg_policy['RSASHA256'] = copy(p) + self.alg_policy['RSASHA256'].algorithm = "RSASHA256" + self.alg_policy['RSASHA256'].name = "RSASHA256" + + self.alg_policy['RSASHA512'] = copy(p) + self.alg_policy['RSASHA512'].algorithm = "RSASHA512" + self.alg_policy['RSASHA512'].name = "RSASHA512" + + self.alg_policy['ECCGOST'] = copy(p) + self.alg_policy['ECCGOST'].algorithm = "ECCGOST" + self.alg_policy['ECCGOST'].name = "ECCGOST" + + self.alg_policy['ECDSAP256SHA256'] = copy(p) + self.alg_policy['ECDSAP256SHA256'].algorithm = "ECDSAP256SHA256" + self.alg_policy['ECDSAP256SHA256'].name = "ECDSAP256SHA256" + self.alg_policy['ECDSAP256SHA256'].ksk_keysize = None; + self.alg_policy['ECDSAP256SHA256'].zsk_keysize = None; + + self.alg_policy['ECDSAP384SHA384'] = copy(p) + self.alg_policy['ECDSAP384SHA384'].algorithm = "ECDSAP384SHA384" + self.alg_policy['ECDSAP384SHA384'].name = "ECDSAP384SHA384" + self.alg_policy['ECDSAP384SHA384'].ksk_keysize = None; + self.alg_policy['ECDSAP384SHA384'].zsk_keysize = None; + + self.alg_policy['ED25519'] = copy(p) + self.alg_policy['ED25519'].algorithm = "ED25519" + self.alg_policy['ED25519'].name = "ED25519" + self.alg_policy['ED25519'].ksk_keysize = None; + self.alg_policy['ED25519'].zsk_keysize = None; + + self.alg_policy['ED448'] = copy(p) + self.alg_policy['ED448'].algorithm = "ED448" + self.alg_policy['ED448'].name = "ED448" + self.alg_policy['ED448'].ksk_keysize = None; + self.alg_policy['ED448'].zsk_keysize = None; + + if filename: + self.load(filename) + + def load(self, filename): + self.filename = filename + self.initial = True + with open(filename) as f: + text = f.read() + self.plex.lexer.lineno = 0 + self.parser.parse(text) + + self.filename = None + + def setup(self, text): + self.initial = True + self.plex.lexer.lineno = 0 + self.parser.parse(text) + + def policy(self, zone, **kwargs): + z = zone.lower() + p = None + + if z in self.zone_policy: + p = self.zone_policy[z] + + if p is None: + p = copy(self.named_policy['default']) + p.name = zone + p.is_constructed = True + + if p.algorithm is None: + parent = p.parent or self.named_policy['default'] + while parent and not parent.algorithm: + parent = parent.parent + p.algorithm = parent and parent.algorithm or None + + if p.algorithm in self.alg_policy: + ap = self.alg_policy[p.algorithm] + else: + raise PolicyException('algorithm not found') + + if p.directory is None: + parent = p.parent or self.named_policy['default'] + while parent is not None and not parent.directory: + parent = parent.parent + p.directory = parent and parent.directory + + if p.coverage is None: + parent = p.parent or self.named_policy['default'] + while parent and not parent.coverage: + parent = parent.parent + p.coverage = parent and parent.coverage or ap.coverage + + if p.ksk_keysize is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.ksk_keysize: + parent = parent.parent + p.ksk_keysize = parent and parent.ksk_keysize or ap.ksk_keysize + + if p.zsk_keysize is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.zsk_keysize: + parent = parent.parent + p.zsk_keysize = parent and parent.zsk_keysize or ap.zsk_keysize + + if p.ksk_rollperiod is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.ksk_rollperiod: + parent = parent.parent + p.ksk_rollperiod = parent and \ + parent.ksk_rollperiod or ap.ksk_rollperiod + + if p.zsk_rollperiod is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.zsk_rollperiod: + parent = parent.parent + p.zsk_rollperiod = parent and \ + parent.zsk_rollperiod or ap.zsk_rollperiod + + if p.ksk_prepublish is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.ksk_prepublish: + parent = parent.parent + p.ksk_prepublish = parent and \ + parent.ksk_prepublish or ap.ksk_prepublish + + if p.zsk_prepublish is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.zsk_prepublish: + parent = parent.parent + p.zsk_prepublish = parent and \ + parent.zsk_prepublish or ap.zsk_prepublish + + if p.ksk_postpublish is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.ksk_postpublish: + parent = parent.parent + p.ksk_postpublish = parent and \ + parent.ksk_postpublish or ap.ksk_postpublish + + if p.zsk_postpublish is None: + parent = p.parent or self.named_policy['default'] + while parent.parent and not parent.zsk_postpublish: + parent = parent.parent + p.zsk_postpublish = parent and \ + parent.zsk_postpublish or ap.zsk_postpublish + + if p.keyttl is None: + parent = p.parent or self.named_policy['default'] + while parent is not None and not parent.keyttl: + parent = parent.parent + p.keyttl = parent and parent.keyttl + + if 'novalidate' not in kwargs or not kwargs['novalidate']: + (valid, msg) = p.validate() + if not valid: + raise PolicyException(msg) + return None + + return p + + + def p_policylist(self, p): + '''policylist : init policy + | policylist policy''' + pass + + def p_init(self, p): + "init :" + self.initial = False + + def p_policy(self, p): + '''policy : alg_policy + | zone_policy + | named_policy''' + pass + + def p_name(self, p): + '''name : STR + | KEYTYPE + | DATESUFFIX''' + p[0] = p[1] + pass + + def p_domain(self, p): + '''domain : STR + | QSTRING + | KEYTYPE + | DATESUFFIX''' + p[0] = p[1].strip() + if not re.match(r'^[\w.-][\w.-]*$', p[0]): + raise PolicyException('invalid domain') + pass + + def p_new_policy(self, p): + "new_policy :" + self.current = Policy() + + def p_alg_policy(self, p): + "alg_policy : ALGORITHM_POLICY ALGNAME new_policy alg_option_group SEMI" + self.current.name = p[2] + self.current.is_alg = True + self.alg_policy[p[2]] = self.current + pass + + def p_zone_policy(self, p): + "zone_policy : ZONE domain new_policy policy_option_group SEMI" + self.current.name = p[2].rstrip('.') + self.current.is_zone = True + self.zone_policy[p[2].rstrip('.').lower()] = self.current + pass + + def p_named_policy(self, p): + "named_policy : POLICY name new_policy policy_option_group SEMI" + self.current.name = p[2] + self.named_policy[p[2].lower()] = self.current + pass + + def p_duration_1(self, p): + "duration : NUMBER" + p[0] = p[1] + pass + + def p_duration_2(self, p): + "duration : NONE" + p[0] = None + pass + + def p_duration_3(self, p): + "duration : NUMBER DATESUFFIX" + if p[2] == "y": + p[0] = p[1] * 31536000 # year + elif p[2] == "mo": + p[0] = p[1] * 2592000 # month + elif p[2] == "w": + p[0] = p[1] * 604800 # week + elif p[2] == "d": + p[0] = p[1] * 86400 # day + elif p[2] == "h": + p[0] = p[1] * 3600 # hour + elif p[2] == "mi": + p[0] = p[1] * 60 # minute + elif p[2] == "s": + p[0] = p[1] # second + else: + raise PolicyException('invalid duration') + + def p_policy_option_group(self, p): + "policy_option_group : LBRACE policy_option_list RBRACE" + pass + + def p_policy_option_list(self, p): + '''policy_option_list : policy_option SEMI + | policy_option_list policy_option SEMI''' + pass + + def p_policy_option(self, p): + '''policy_option : parent_option + | directory_option + | coverage_option + | rollperiod_option + | prepublish_option + | postpublish_option + | keysize_option + | algorithm_option + | keyttl_option + | standby_option''' + pass + + def p_alg_option_group(self, p): + "alg_option_group : LBRACE alg_option_list RBRACE" + pass + + def p_alg_option_list(self, p): + '''alg_option_list : alg_option SEMI + | alg_option_list alg_option SEMI''' + pass + + def p_alg_option(self, p): + '''alg_option : coverage_option + | rollperiod_option + | prepublish_option + | postpublish_option + | keyttl_option + | keysize_option + | standby_option''' + pass + + def p_parent_option(self, p): + "parent_option : POLICY name" + self.current.parent = self.named_policy[p[2].lower()] + + def p_directory_option(self, p): + "directory_option : DIRECTORY QSTRING" + self.current.directory = p[2] + + def p_coverage_option(self, p): + "coverage_option : COVERAGE duration" + self.current.coverage = p[2] + + def p_rollperiod_option(self, p): + "rollperiod_option : ROLL_PERIOD KEYTYPE duration" + if p[2] == "KSK": + self.current.ksk_rollperiod = p[3] + else: + self.current.zsk_rollperiod = p[3] + + def p_prepublish_option(self, p): + "prepublish_option : PRE_PUBLISH KEYTYPE duration" + if p[2] == "KSK": + self.current.ksk_prepublish = p[3] + else: + self.current.zsk_prepublish = p[3] + + def p_postpublish_option(self, p): + "postpublish_option : POST_PUBLISH KEYTYPE duration" + if p[2] == "KSK": + self.current.ksk_postpublish = p[3] + else: + self.current.zsk_postpublish = p[3] + + def p_keysize_option(self, p): + "keysize_option : KEY_SIZE KEYTYPE NUMBER" + if p[2] == "KSK": + self.current.ksk_keysize = p[3] + else: + self.current.zsk_keysize = p[3] + + def p_standby_option(self, p): + "standby_option : STANDBY KEYTYPE NUMBER" + if p[2] == "KSK": + self.current.ksk_standby = p[3] + else: + self.current.zsk_standby = p[3] + + def p_keyttl_option(self, p): + "keyttl_option : KEYTTL duration" + self.current.keyttl = p[2] + + def p_algorithm_option(self, p): + "algorithm_option : ALGORITHM ALGNAME" + self.current.algorithm = p[2] + + def p_error(self, p): + if p: + print("%s%s%d:syntax error near '%s'" % + (self.filename or "", ":" if self.filename else "", + p.lineno, p.value)) + else: + if not self.initial: + raise PolicyException("%s%s%d:unexpected end of input" % + (self.filename or "", ":" if self.filename else "", + p and p.lineno or 0)) + +if __name__ == "__main__": + import sys + if sys.argv[1] == "lex": + file = open(sys.argv[2]) + text = file.read() + file.close() + plex = PolicyLex(debug=1) + plex.test(text) + elif sys.argv[1] == "parse": + try: + pp = dnssec_policy(sys.argv[2], write_tables=True, debug=True) + print(pp.named_policy['default']) + print(pp.policy("nonexistent.zone")) + except Exception as e: + print(e.args[0]) |