diff options
Diffstat (limited to 'Lib/ipaddress.py')
| -rw-r--r-- | Lib/ipaddress.py | 363 |
1 files changed, 235 insertions, 128 deletions
diff --git a/Lib/ipaddress.py b/Lib/ipaddress.py index 54df39ae56..4f02d520f1 100644 --- a/Lib/ipaddress.py +++ b/Lib/ipaddress.py @@ -195,11 +195,7 @@ def _count_righthand_zero_bits(number, bits): """ if number == 0: return bits - for i in range(bits): - if (number >> i) & 1: - return i - # All bits of interest were zero, even if there are more in the number - return bits + return min(bits, (~number & (number-1)).bit_length()) def summarize_address_range(first, last): @@ -250,15 +246,14 @@ def summarize_address_range(first, last): while first_int <= last_int: nbits = min(_count_righthand_zero_bits(first_int, ip_bits), (last_int - first_int + 1).bit_length() - 1) - net = ip('%s/%d' % (first, ip_bits - nbits)) + net = ip((first_int, ip_bits - nbits)) yield net first_int += 1 << nbits if first_int - 1 == ip._ALL_ONES: break - first = first.__class__(first_int) -def _collapse_addresses_recursive(addresses): +def _collapse_addresses_internal(addresses): """Loops through the addresses, collapsing concurrent netblocks. Example: @@ -268,7 +263,7 @@ def _collapse_addresses_recursive(addresses): ip3 = IPv4Network('192.0.2.128/26') ip4 = IPv4Network('192.0.2.192/26') - _collapse_addresses_recursive([ip1, ip2, ip3, ip4]) -> + _collapse_addresses_internal([ip1, ip2, ip3, ip4]) -> [IPv4Network('192.0.2.0/24')] This shouldn't be called directly; it is called via @@ -282,28 +277,29 @@ def _collapse_addresses_recursive(addresses): passed. """ - while True: - last_addr = None - ret_array = [] - optimized = False - - for cur_addr in addresses: - if not ret_array: - last_addr = cur_addr - ret_array.append(cur_addr) - elif (cur_addr.network_address >= last_addr.network_address and - cur_addr.broadcast_address <= last_addr.broadcast_address): - optimized = True - elif cur_addr == list(last_addr.supernet().subnets())[1]: - ret_array[-1] = last_addr = last_addr.supernet() - optimized = True - else: - last_addr = cur_addr - ret_array.append(cur_addr) - - addresses = ret_array - if not optimized: - return addresses + # First merge + to_merge = list(addresses) + subnets = {} + while to_merge: + net = to_merge.pop() + supernet = net.supernet() + existing = subnets.get(supernet) + if existing is None: + subnets[supernet] = net + elif existing != net: + # Merge consecutive subnets + del subnets[supernet] + to_merge.append(supernet) + # Then iterate over resulting networks, skipping subsumed subnets + last = None + for net in sorted(subnets.values()): + if last is not None: + # Since they are sorted, last.network_address <= net.network_address + # is a given. + if last.broadcast_address >= net.broadcast_address: + continue + yield net + last = net def collapse_addresses(addresses): @@ -352,15 +348,13 @@ def collapse_addresses(addresses): # sort and dedup ips = sorted(set(ips)) - nets = sorted(set(nets)) while i < len(ips): (first, last) = _find_address_range(ips[i:]) i = ips.index(last) + 1 addrs.extend(summarize_address_range(first, last)) - return iter(_collapse_addresses_recursive(sorted( - addrs + nets, key=_BaseNetwork._get_networks_key))) + return _collapse_addresses_internal(addrs + nets) def get_mixed_type_key(obj): @@ -436,6 +430,17 @@ class _IPAddressBase(_TotalOrderingMixin): return str(self) @property + def reverse_pointer(self): + """The name of the reverse DNS pointer for the IP address, e.g.: + >>> ipaddress.ip_address("127.0.0.1").reverse_pointer + '1.0.0.127.in-addr.arpa' + >>> ipaddress.ip_address("2001:db8::1").reverse_pointer + '1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa' + + """ + return self._reverse_pointer() + + @property def version(self): msg = '%200s has no version specified' % (type(self),) raise NotImplementedError(msg) @@ -456,7 +461,8 @@ class _IPAddressBase(_TotalOrderingMixin): raise AddressValueError(msg % (address, address_len, expected_len, self._version)) - def _ip_int_from_prefix(self, prefixlen): + @classmethod + def _ip_int_from_prefix(cls, prefixlen): """Turn the prefix length into a bitwise netmask Args: @@ -466,9 +472,10 @@ class _IPAddressBase(_TotalOrderingMixin): An integer. """ - return self._ALL_ONES ^ (self._ALL_ONES >> prefixlen) + return cls._ALL_ONES ^ (cls._ALL_ONES >> prefixlen) - def _prefix_from_ip_int(self, ip_int): + @classmethod + def _prefix_from_ip_int(cls, ip_int): """Return prefix length from the bitwise netmask. Args: @@ -481,22 +488,24 @@ class _IPAddressBase(_TotalOrderingMixin): ValueError: If the input intermingles zeroes & ones """ trailing_zeroes = _count_righthand_zero_bits(ip_int, - self._max_prefixlen) - prefixlen = self._max_prefixlen - trailing_zeroes + cls._max_prefixlen) + prefixlen = cls._max_prefixlen - trailing_zeroes leading_ones = ip_int >> trailing_zeroes all_ones = (1 << prefixlen) - 1 if leading_ones != all_ones: - byteslen = self._max_prefixlen // 8 + byteslen = cls._max_prefixlen // 8 details = ip_int.to_bytes(byteslen, 'big') msg = 'Netmask pattern %r mixes zeroes & ones' raise ValueError(msg % details) return prefixlen - def _report_invalid_netmask(self, netmask_str): + @classmethod + def _report_invalid_netmask(cls, netmask_str): msg = '%r is not a valid netmask' % netmask_str raise NetmaskValueError(msg) from None - def _prefix_from_prefix_string(self, prefixlen_str): + @classmethod + def _prefix_from_prefix_string(cls, prefixlen_str): """Return prefix length from a numeric string Args: @@ -511,16 +520,17 @@ class _IPAddressBase(_TotalOrderingMixin): # int allows a leading +/- as well as surrounding whitespace, # so we ensure that isn't the case if not _BaseV4._DECIMAL_DIGITS.issuperset(prefixlen_str): - self._report_invalid_netmask(prefixlen_str) + cls._report_invalid_netmask(prefixlen_str) try: prefixlen = int(prefixlen_str) except ValueError: - self._report_invalid_netmask(prefixlen_str) - if not (0 <= prefixlen <= self._max_prefixlen): - self._report_invalid_netmask(prefixlen_str) + cls._report_invalid_netmask(prefixlen_str) + if not (0 <= prefixlen <= cls._max_prefixlen): + cls._report_invalid_netmask(prefixlen_str) return prefixlen - def _prefix_from_ip_string(self, ip_str): + @classmethod + def _prefix_from_ip_string(cls, ip_str): """Turn a netmask/hostmask string into a prefix length Args: @@ -534,24 +544,24 @@ class _IPAddressBase(_TotalOrderingMixin): """ # Parse the netmask/hostmask like an IP address. try: - ip_int = self._ip_int_from_string(ip_str) + ip_int = cls._ip_int_from_string(ip_str) except AddressValueError: - self._report_invalid_netmask(ip_str) + cls._report_invalid_netmask(ip_str) # Try matching a netmask (this would be /1*0*/ as a bitwise regexp). # Note that the two ambiguous cases (all-ones and all-zeroes) are # treated as netmasks. try: - return self._prefix_from_ip_int(ip_int) + return cls._prefix_from_ip_int(ip_int) except ValueError: pass # Invert the bits, and try matching a /0+1+/ hostmask instead. - ip_int ^= self._ALL_ONES + ip_int ^= cls._ALL_ONES try: - return self._prefix_from_ip_int(ip_int) + return cls._prefix_from_ip_int(ip_int) except ValueError: - self._report_invalid_netmask(ip_str) + cls._report_invalid_netmask(ip_str) class _BaseAddress(_IPAddressBase): @@ -933,20 +943,11 @@ class _BaseNetwork(_IPAddressBase): 'prefix length diff %d is invalid for netblock %s' % ( new_prefixlen, self)) - first = self.__class__('%s/%s' % - (self.network_address, - self._prefixlen + prefixlen_diff)) - - yield first - current = first - while True: - broadcast = current.broadcast_address - if broadcast == self.broadcast_address: - return - new_addr = self._address_class(int(broadcast) + 1) - current = self.__class__('%s/%s' % (new_addr, - new_prefixlen)) - + start = int(self.network_address) + end = int(self.broadcast_address) + step = (int(self.hostmask) + 1) >> prefixlen_diff + for new_addr in range(start, end, step): + current = self.__class__((new_addr, new_prefixlen)) yield current def supernet(self, prefixlen_diff=1, new_prefix=None): @@ -980,15 +981,15 @@ class _BaseNetwork(_IPAddressBase): raise ValueError('cannot set prefixlen_diff and new_prefix') prefixlen_diff = self._prefixlen - new_prefix - if self.prefixlen - prefixlen_diff < 0: + new_prefixlen = self.prefixlen - prefixlen_diff + if new_prefixlen < 0: raise ValueError( 'current prefixlen is %d, cannot have a prefixlen_diff of %d' % (self.prefixlen, prefixlen_diff)) - # TODO (pmoody): optimize this. - t = self.__class__('%s/%d' % (self.network_address, - self.prefixlen - prefixlen_diff), - strict=False) - return t.__class__('%s/%d' % (t.network_address, t.prefixlen)) + return self.__class__(( + int(self.network_address) & (int(self.netmask) << prefixlen_diff), + new_prefixlen + )) @property def is_multicast(self): @@ -1089,14 +1090,43 @@ class _BaseV4: # the valid octets for host and netmasks. only useful for IPv4. _valid_mask_octets = frozenset((255, 254, 252, 248, 240, 224, 192, 128, 0)) + _max_prefixlen = IPV4LENGTH + # There are only a handful of valid v4 netmasks, so we cache them all + # when constructed (see _make_netmask()). + _netmask_cache = {} + def __init__(self, address): self._version = 4 - self._max_prefixlen = IPV4LENGTH def _explode_shorthand_ip_string(self): return str(self) - def _ip_int_from_string(self, ip_str): + @classmethod + def _make_netmask(cls, arg): + """Make a (netmask, prefix_len) tuple from the given argument. + + Argument can be: + - an integer (the prefix length) + - a string representing the prefix length (e.g. "24") + - a string representing the prefix netmask (e.g. "255.255.255.0") + """ + if arg not in cls._netmask_cache: + if isinstance(arg, int): + prefixlen = arg + else: + try: + # Check for a netmask in prefix length form + prefixlen = cls._prefix_from_prefix_string(arg) + except NetmaskValueError: + # Check for a netmask or hostmask in dotted-quad form. + # This may raise NetmaskValueError. + prefixlen = cls._prefix_from_ip_string(arg) + netmask = IPv4Address(cls._ip_int_from_prefix(prefixlen)) + cls._netmask_cache[arg] = netmask, prefixlen + return cls._netmask_cache[arg] + + @classmethod + def _ip_int_from_string(cls, ip_str): """Turn the given IP string into an integer for comparison. Args: @@ -1117,11 +1147,12 @@ class _BaseV4: raise AddressValueError("Expected 4 octets in %r" % ip_str) try: - return int.from_bytes(map(self._parse_octet, octets), 'big') + return int.from_bytes(map(cls._parse_octet, octets), 'big') except ValueError as exc: raise AddressValueError("%s in %r" % (exc, ip_str)) from None - def _parse_octet(self, octet_str): + @classmethod + def _parse_octet(cls, octet_str): """Convert a decimal octet into an integer. Args: @@ -1137,7 +1168,7 @@ class _BaseV4: if not octet_str: raise ValueError("Empty octet not permitted") # Whitelist the characters, since int() allows a lot of bizarre stuff. - if not self._DECIMAL_DIGITS.issuperset(octet_str): + if not cls._DECIMAL_DIGITS.issuperset(octet_str): msg = "Only decimal digits permitted in %r" raise ValueError(msg % octet_str) # We do the length check second, since the invalid character error @@ -1157,7 +1188,8 @@ class _BaseV4: raise ValueError("Octet %d (> 255) not permitted" % octet_int) return octet_int - def _string_from_ip_int(self, ip_int): + @classmethod + def _string_from_ip_int(cls, ip_int): """Turns a 32-bit integer into dotted decimal notation. Args: @@ -1221,6 +1253,15 @@ class _BaseV4: return True return False + def _reverse_pointer(self): + """Return the reverse DNS pointer name for the IPv4 address. + + This implements the method described in RFC1035 3.5. + + """ + reverse_octets = str(self).split('.')[::-1] + return '.'.join(reverse_octets) + '.in-addr.arpa' + @property def max_prefixlen(self): return self._max_prefixlen @@ -1369,6 +1410,18 @@ class IPv4Interface(IPv4Address): self._prefixlen = self._max_prefixlen return + if isinstance(address, tuple): + IPv4Address.__init__(self, address[0]) + if len(address) > 1: + self._prefixlen = int(address[1]) + else: + self._prefixlen = self._max_prefixlen + + self.network = IPv4Network(address, strict=False) + self.netmask = self.network.netmask + self.hostmask = self.network.hostmask + return + addr = _split_optional_netmask(address) IPv4Address.__init__(self, addr[0]) @@ -1484,20 +1537,28 @@ class IPv4Network(_BaseV4, _BaseNetwork): _BaseV4.__init__(self, address) _BaseNetwork.__init__(self, address) - # Constructing from a packed address - if isinstance(address, bytes): + # Constructing from a packed address or integer + if isinstance(address, (int, bytes)): self.network_address = IPv4Address(address) - self._prefixlen = self._max_prefixlen - self.netmask = IPv4Address(self._ALL_ONES) - #fixme: address/network test here + self.netmask, self._prefixlen = self._make_netmask(self._max_prefixlen) + #fixme: address/network test here. return - # Efficient constructor from integer. - if isinstance(address, int): - self.network_address = IPv4Address(address) - self._prefixlen = self._max_prefixlen - self.netmask = IPv4Address(self._ALL_ONES) - #fixme: address/network test here. + if isinstance(address, tuple): + if len(address) > 1: + arg = address[1] + else: + # We weren't given an address[1] + arg = self._max_prefixlen + self.network_address = IPv4Address(address[0]) + self.netmask, self._prefixlen = self._make_netmask(arg) + packed = int(self.network_address) + if packed & int(self.netmask) != packed: + if strict: + raise ValueError('%s has host bits set' % self) + else: + self.network_address = IPv4Address(packed & + int(self.netmask)) return # Assume input argument to be string or any object representation @@ -1506,16 +1567,10 @@ class IPv4Network(_BaseV4, _BaseNetwork): self.network_address = IPv4Address(self._ip_int_from_string(addr[0])) if len(addr) == 2: - try: - # Check for a netmask in prefix length form - self._prefixlen = self._prefix_from_prefix_string(addr[1]) - except NetmaskValueError: - # Check for a netmask or hostmask in dotted-quad form. - # This may raise NetmaskValueError. - self._prefixlen = self._prefix_from_ip_string(addr[1]) + arg = addr[1] else: - self._prefixlen = self._max_prefixlen - self.netmask = IPv4Address(self._ip_int_from_prefix(self._prefixlen)) + arg = self._max_prefixlen + self.netmask, self._prefixlen = self._make_netmask(arg) if strict: if (IPv4Address(int(self.network_address) & int(self.netmask)) != @@ -1555,12 +1610,35 @@ class _BaseV6: _ALL_ONES = (2**IPV6LENGTH) - 1 _HEXTET_COUNT = 8 _HEX_DIGITS = frozenset('0123456789ABCDEFabcdef') + _max_prefixlen = IPV6LENGTH + + # There are only a bunch of valid v6 netmasks, so we cache them all + # when constructed (see _make_netmask()). + _netmask_cache = {} def __init__(self, address): self._version = 6 - self._max_prefixlen = IPV6LENGTH - def _ip_int_from_string(self, ip_str): + @classmethod + def _make_netmask(cls, arg): + """Make a (netmask, prefix_len) tuple from the given argument. + + Argument can be: + - an integer (the prefix length) + - a string representing the prefix length (e.g. "24") + - a string representing the prefix netmask (e.g. "255.255.255.0") + """ + if arg not in cls._netmask_cache: + if isinstance(arg, int): + prefixlen = arg + else: + prefixlen = cls._prefix_from_prefix_string(arg) + netmask = IPv6Address(cls._ip_int_from_prefix(prefixlen)) + cls._netmask_cache[arg] = netmask, prefixlen + return cls._netmask_cache[arg] + + @classmethod + def _ip_int_from_string(cls, ip_str): """Turn an IPv6 ip_str into an integer. Args: @@ -1596,7 +1674,7 @@ class _BaseV6: # An IPv6 address can't have more than 8 colons (9 parts). # The extra colon comes from using the "::" notation for a single # leading or trailing zero part. - _max_parts = self._HEXTET_COUNT + 1 + _max_parts = cls._HEXTET_COUNT + 1 if len(parts) > _max_parts: msg = "At most %d colons permitted in %r" % (_max_parts-1, ip_str) raise AddressValueError(msg) @@ -1628,17 +1706,17 @@ class _BaseV6: if parts_lo: msg = "Trailing ':' only permitted as part of '::' in %r" raise AddressValueError(msg % ip_str) # :$ requires ::$ - parts_skipped = self._HEXTET_COUNT - (parts_hi + parts_lo) + parts_skipped = cls._HEXTET_COUNT - (parts_hi + parts_lo) if parts_skipped < 1: msg = "Expected at most %d other parts with '::' in %r" - raise AddressValueError(msg % (self._HEXTET_COUNT-1, ip_str)) + raise AddressValueError(msg % (cls._HEXTET_COUNT-1, ip_str)) else: # Otherwise, allocate the entire address to parts_hi. The # endpoints could still be empty, but _parse_hextet() will check # for that. - if len(parts) != self._HEXTET_COUNT: + if len(parts) != cls._HEXTET_COUNT: msg = "Exactly %d parts expected without '::' in %r" - raise AddressValueError(msg % (self._HEXTET_COUNT, ip_str)) + raise AddressValueError(msg % (cls._HEXTET_COUNT, ip_str)) if not parts[0]: msg = "Leading ':' only permitted as part of '::' in %r" raise AddressValueError(msg % ip_str) # ^: requires ^:: @@ -1654,16 +1732,17 @@ class _BaseV6: ip_int = 0 for i in range(parts_hi): ip_int <<= 16 - ip_int |= self._parse_hextet(parts[i]) + ip_int |= cls._parse_hextet(parts[i]) ip_int <<= 16 * parts_skipped for i in range(-parts_lo, 0): ip_int <<= 16 - ip_int |= self._parse_hextet(parts[i]) + ip_int |= cls._parse_hextet(parts[i]) return ip_int except ValueError as exc: raise AddressValueError("%s in %r" % (exc, ip_str)) from None - def _parse_hextet(self, hextet_str): + @classmethod + def _parse_hextet(cls, hextet_str): """Convert an IPv6 hextet string into an integer. Args: @@ -1678,7 +1757,7 @@ class _BaseV6: """ # Whitelist the characters, since int() allows a lot of bizarre stuff. - if not self._HEX_DIGITS.issuperset(hextet_str): + if not cls._HEX_DIGITS.issuperset(hextet_str): raise ValueError("Only hex digits permitted in %r" % hextet_str) # We do the length check second, since the invalid character error # is likely to be more informative for the user @@ -1688,7 +1767,8 @@ class _BaseV6: # Length check means we can skip checking the integer value return int(hextet_str, 16) - def _compress_hextets(self, hextets): + @classmethod + def _compress_hextets(cls, hextets): """Compresses a list of hextets. Compresses a list of strings, replacing the longest continuous @@ -1735,7 +1815,8 @@ class _BaseV6: return hextets - def _string_from_ip_int(self, ip_int=None): + @classmethod + def _string_from_ip_int(cls, ip_int=None): """Turns a 128-bit integer into hexadecimal notation. Args: @@ -1749,15 +1830,15 @@ class _BaseV6: """ if ip_int is None: - ip_int = int(self._ip) + ip_int = int(cls._ip) - if ip_int > self._ALL_ONES: + if ip_int > cls._ALL_ONES: raise ValueError('IPv6 address is too large') hex_str = '%032x' % ip_int hextets = ['%x' % int(hex_str[x:x+4], 16) for x in range(0, 32, 4)] - hextets = self._compress_hextets(hextets) + hextets = cls._compress_hextets(hextets) return ':'.join(hextets) def _explode_shorthand_ip_string(self): @@ -1784,6 +1865,15 @@ class _BaseV6: return '%s/%d' % (':'.join(parts), self._prefixlen) return ':'.join(parts) + def _reverse_pointer(self): + """Return the reverse DNS pointer name for the IPv6 address. + + This implements the method described in RFC3596 2.5. + + """ + reverse_chars = self.exploded[::-1].replace(':', '') + return '.'.join(reverse_chars) + '.ip6.arpa' + @property def max_prefixlen(self): return self._max_prefixlen @@ -2001,6 +2091,16 @@ class IPv6Interface(IPv6Address): self.network = IPv6Network(self._ip) self._prefixlen = self._max_prefixlen return + if isinstance(address, tuple): + IPv6Address.__init__(self, address[0]) + if len(address) > 1: + self._prefixlen = int(address[1]) + else: + self._prefixlen = self._max_prefixlen + self.network = IPv6Network(address, strict=False) + self.netmask = self.network.netmask + self.hostmask = self.network.hostmask + return addr = _split_optional_netmask(address) IPv6Address.__init__(self, addr[0]) @@ -2118,18 +2218,26 @@ class IPv6Network(_BaseV6, _BaseNetwork): _BaseV6.__init__(self, address) _BaseNetwork.__init__(self, address) - # Efficient constructor from integer. - if isinstance(address, int): + # Efficient constructor from integer or packed address + if isinstance(address, (bytes, int)): self.network_address = IPv6Address(address) - self._prefixlen = self._max_prefixlen - self.netmask = IPv6Address(self._ALL_ONES) + self.netmask, self._prefixlen = self._make_netmask(self._max_prefixlen) return - # Constructing from a packed address - if isinstance(address, bytes): - self.network_address = IPv6Address(address) - self._prefixlen = self._max_prefixlen - self.netmask = IPv6Address(self._ALL_ONES) + if isinstance(address, tuple): + if len(address) > 1: + arg = address[1] + else: + arg = self._max_prefixlen + self.netmask, self._prefixlen = self._make_netmask(arg) + self.network_address = IPv6Address(address[0]) + packed = int(self.network_address) + if packed & int(self.netmask) != packed: + if strict: + raise ValueError('%s has host bits set' % self) + else: + self.network_address = IPv6Address(packed & + int(self.netmask)) return # Assume input argument to be string or any object representation @@ -2139,12 +2247,11 @@ class IPv6Network(_BaseV6, _BaseNetwork): self.network_address = IPv6Address(self._ip_int_from_string(addr[0])) if len(addr) == 2: - # This may raise NetmaskValueError - self._prefixlen = self._prefix_from_prefix_string(addr[1]) + arg = addr[1] else: - self._prefixlen = self._max_prefixlen + arg = self._max_prefixlen + self.netmask, self._prefixlen = self._make_netmask(arg) - self.netmask = IPv6Address(self._ip_int_from_prefix(self._prefixlen)) if strict: if (IPv6Address(int(self.network_address) & int(self.netmask)) != self.network_address): |