| r"""UUID objects (universally unique identifiers) according to RFC 4122. |
| |
| This module provides immutable UUID objects (class UUID) and the functions |
| uuid1(), uuid3(), uuid4(), uuid5() for generating version 1, 3, 4, and 5 |
| UUIDs as specified in RFC 4122. |
| |
| If all you want is a unique ID, you should probably call uuid1() or uuid4(). |
| Note that uuid1() may compromise privacy since it creates a UUID containing |
| the computer's network address. uuid4() creates a random UUID. |
| |
| Typical usage: |
| |
| >>> import uuid |
| |
| # make a UUID based on the host ID and current time |
| >>> uuid.uuid1() # doctest: +SKIP |
| UUID('a8098c1a-f86e-11da-bd1a-00112444be1e') |
| |
| # make a UUID using an MD5 hash of a namespace UUID and a name |
| >>> uuid.uuid3(uuid.NAMESPACE_DNS, 'python.org') |
| UUID('6fa459ea-ee8a-3ca4-894e-db77e160355e') |
| |
| # make a random UUID |
| >>> uuid.uuid4() # doctest: +SKIP |
| UUID('16fd2706-8baf-433b-82eb-8c7fada847da') |
| |
| # make a UUID using a SHA-1 hash of a namespace UUID and a name |
| >>> uuid.uuid5(uuid.NAMESPACE_DNS, 'python.org') |
| UUID('886313e1-3b8a-5372-9b90-0c9aee199e5d') |
| |
| # make a UUID from a string of hex digits (braces and hyphens ignored) |
| >>> x = uuid.UUID('{00010203-0405-0607-0809-0a0b0c0d0e0f}') |
| |
| # convert a UUID to a string of hex digits in standard form |
| >>> str(x) |
| '00010203-0405-0607-0809-0a0b0c0d0e0f' |
| |
| # get the raw 16 bytes of the UUID |
| >>> x.bytes |
| b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f' |
| |
| # make a UUID from a 16-byte string |
| >>> uuid.UUID(bytes=x.bytes) |
| UUID('00010203-0405-0607-0809-0a0b0c0d0e0f') |
| """ |
| |
| import os |
| import sys |
| |
| from enum import Enum |
| |
| |
| __author__ = 'Ka-Ping Yee <ping@zesty.ca>' |
| |
| # The recognized platforms - known behaviors |
| if sys.platform in ('win32', 'darwin'): |
| _AIX = _LINUX = False |
| else: |
| import platform |
| _platform_system = platform.system() |
| _AIX = _platform_system == 'AIX' |
| _LINUX = _platform_system == 'Linux' |
| |
| _MAC_DELIM = b':' |
| _MAC_OMITS_LEADING_ZEROES = False |
| if _AIX: |
| _MAC_DELIM = b'.' |
| _MAC_OMITS_LEADING_ZEROES = True |
| |
| RESERVED_NCS, RFC_4122, RESERVED_MICROSOFT, RESERVED_FUTURE = [ |
| 'reserved for NCS compatibility', 'specified in RFC 4122', |
| 'reserved for Microsoft compatibility', 'reserved for future definition'] |
| |
| int_ = int # The built-in int type |
| bytes_ = bytes # The built-in bytes type |
| |
| |
| class SafeUUID(Enum): |
| safe = 0 |
| unsafe = -1 |
| unknown = None |
| |
| |
| class UUID: |
| """Instances of the UUID class represent UUIDs as specified in RFC 4122. |
| UUID objects are immutable, hashable, and usable as dictionary keys. |
| Converting a UUID to a string with str() yields something in the form |
| '12345678-1234-1234-1234-123456789abc'. The UUID constructor accepts |
| five possible forms: a similar string of hexadecimal digits, or a tuple |
| of six integer fields (with 32-bit, 16-bit, 16-bit, 8-bit, 8-bit, and |
| 48-bit values respectively) as an argument named 'fields', or a string |
| of 16 bytes (with all the integer fields in big-endian order) as an |
| argument named 'bytes', or a string of 16 bytes (with the first three |
| fields in little-endian order) as an argument named 'bytes_le', or a |
| single 128-bit integer as an argument named 'int'. |
| |
| UUIDs have these read-only attributes: |
| |
| bytes the UUID as a 16-byte string (containing the six |
| integer fields in big-endian byte order) |
| |
| bytes_le the UUID as a 16-byte string (with time_low, time_mid, |
| and time_hi_version in little-endian byte order) |
| |
| fields a tuple of the six integer fields of the UUID, |
| which are also available as six individual attributes |
| and two derived attributes: |
| |
| time_low the first 32 bits of the UUID |
| time_mid the next 16 bits of the UUID |
| time_hi_version the next 16 bits of the UUID |
| clock_seq_hi_variant the next 8 bits of the UUID |
| clock_seq_low the next 8 bits of the UUID |
| node the last 48 bits of the UUID |
| |
| time the 60-bit timestamp |
| clock_seq the 14-bit sequence number |
| |
| hex the UUID as a 32-character hexadecimal string |
| |
| int the UUID as a 128-bit integer |
| |
| urn the UUID as a URN as specified in RFC 4122 |
| |
| variant the UUID variant (one of the constants RESERVED_NCS, |
| RFC_4122, RESERVED_MICROSOFT, or RESERVED_FUTURE) |
| |
| version the UUID version number (1 through 5, meaningful only |
| when the variant is RFC_4122) |
| |
| is_safe An enum indicating whether the UUID has been generated in |
| a way that is safe for multiprocessing applications, via |
| uuid_generate_time_safe(3). |
| """ |
| |
| __slots__ = ('int', 'is_safe', '__weakref__') |
| |
| def __init__(self, hex=None, bytes=None, bytes_le=None, fields=None, |
| int=None, version=None, |
| *, is_safe=SafeUUID.unknown): |
| r"""Create a UUID from either a string of 32 hexadecimal digits, |
| a string of 16 bytes as the 'bytes' argument, a string of 16 bytes |
| in little-endian order as the 'bytes_le' argument, a tuple of six |
| integers (32-bit time_low, 16-bit time_mid, 16-bit time_hi_version, |
| 8-bit clock_seq_hi_variant, 8-bit clock_seq_low, 48-bit node) as |
| the 'fields' argument, or a single 128-bit integer as the 'int' |
| argument. When a string of hex digits is given, curly braces, |
| hyphens, and a URN prefix are all optional. For example, these |
| expressions all yield the same UUID: |
| |
| UUID('{12345678-1234-5678-1234-567812345678}') |
| UUID('12345678123456781234567812345678') |
| UUID('urn:uuid:12345678-1234-5678-1234-567812345678') |
| UUID(bytes='\x12\x34\x56\x78'*4) |
| UUID(bytes_le='\x78\x56\x34\x12\x34\x12\x78\x56' + |
| '\x12\x34\x56\x78\x12\x34\x56\x78') |
| UUID(fields=(0x12345678, 0x1234, 0x5678, 0x12, 0x34, 0x567812345678)) |
| UUID(int=0x12345678123456781234567812345678) |
| |
| Exactly one of 'hex', 'bytes', 'bytes_le', 'fields', or 'int' must |
| be given. The 'version' argument is optional; if given, the resulting |
| UUID will have its variant and version set according to RFC 4122, |
| overriding the given 'hex', 'bytes', 'bytes_le', 'fields', or 'int'. |
| |
| is_safe is an enum exposed as an attribute on the instance. It |
| indicates whether the UUID has been generated in a way that is safe |
| for multiprocessing applications, via uuid_generate_time_safe(3). |
| """ |
| |
| if [hex, bytes, bytes_le, fields, int].count(None) != 4: |
| raise TypeError('one of the hex, bytes, bytes_le, fields, ' |
| 'or int arguments must be given') |
| if hex is not None: |
| hex = hex.replace('urn:', '').replace('uuid:', '') |
| hex = hex.strip('{}').replace('-', '') |
| if len(hex) != 32: |
| raise ValueError('badly formed hexadecimal UUID string') |
| int = int_(hex, 16) |
| if bytes_le is not None: |
| if len(bytes_le) != 16: |
| raise ValueError('bytes_le is not a 16-char string') |
| bytes = (bytes_le[4-1::-1] + bytes_le[6-1:4-1:-1] + |
| bytes_le[8-1:6-1:-1] + bytes_le[8:]) |
| if bytes is not None: |
| if len(bytes) != 16: |
| raise ValueError('bytes is not a 16-char string') |
| assert isinstance(bytes, bytes_), repr(bytes) |
| int = int_.from_bytes(bytes, byteorder='big') |
| if fields is not None: |
| if len(fields) != 6: |
| raise ValueError('fields is not a 6-tuple') |
| (time_low, time_mid, time_hi_version, |
| clock_seq_hi_variant, clock_seq_low, node) = fields |
| if not 0 <= time_low < 1<<32: |
| raise ValueError('field 1 out of range (need a 32-bit value)') |
| if not 0 <= time_mid < 1<<16: |
| raise ValueError('field 2 out of range (need a 16-bit value)') |
| if not 0 <= time_hi_version < 1<<16: |
| raise ValueError('field 3 out of range (need a 16-bit value)') |
| if not 0 <= clock_seq_hi_variant < 1<<8: |
| raise ValueError('field 4 out of range (need an 8-bit value)') |
| if not 0 <= clock_seq_low < 1<<8: |
| raise ValueError('field 5 out of range (need an 8-bit value)') |
| if not 0 <= node < 1<<48: |
| raise ValueError('field 6 out of range (need a 48-bit value)') |
| clock_seq = (clock_seq_hi_variant << 8) | clock_seq_low |
| int = ((time_low << 96) | (time_mid << 80) | |
| (time_hi_version << 64) | (clock_seq << 48) | node) |
| if int is not None: |
| if not 0 <= int < 1<<128: |
| raise ValueError('int is out of range (need a 128-bit value)') |
| if version is not None: |
| if not 1 <= version <= 5: |
| raise ValueError('illegal version number') |
| # Set the variant to RFC 4122. |
| int &= ~(0xc000 << 48) |
| int |= 0x8000 << 48 |
| # Set the version number. |
| int &= ~(0xf000 << 64) |
| int |= version << 76 |
| object.__setattr__(self, 'int', int) |
| object.__setattr__(self, 'is_safe', is_safe) |
| |
| def __getstate__(self): |
| d = {'int': self.int} |
| if self.is_safe != SafeUUID.unknown: |
| # is_safe is a SafeUUID instance. Return just its value, so that |
| # it can be un-pickled in older Python versions without SafeUUID. |
| d['is_safe'] = self.is_safe.value |
| return d |
| |
| def __setstate__(self, state): |
| object.__setattr__(self, 'int', state['int']) |
| # is_safe was added in 3.7; it is also omitted when it is "unknown" |
| object.__setattr__(self, 'is_safe', |
| SafeUUID(state['is_safe']) |
| if 'is_safe' in state else SafeUUID.unknown) |
| |
| def __eq__(self, other): |
| if isinstance(other, UUID): |
| return self.int == other.int |
| return NotImplemented |
| |
| # Q. What's the value of being able to sort UUIDs? |
| # A. Use them as keys in a B-Tree or similar mapping. |
| |
| def __lt__(self, other): |
| if isinstance(other, UUID): |
| return self.int < other.int |
| return NotImplemented |
| |
| def __gt__(self, other): |
| if isinstance(other, UUID): |
| return self.int > other.int |
| return NotImplemented |
| |
| def __le__(self, other): |
| if isinstance(other, UUID): |
| return self.int <= other.int |
| return NotImplemented |
| |
| def __ge__(self, other): |
| if isinstance(other, UUID): |
| return self.int >= other.int |
| return NotImplemented |
| |
| def __hash__(self): |
| return hash(self.int) |
| |
| def __int__(self): |
| return self.int |
| |
| def __repr__(self): |
| return '%s(%r)' % (self.__class__.__name__, str(self)) |
| |
| def __setattr__(self, name, value): |
| raise TypeError('UUID objects are immutable') |
| |
| def __str__(self): |
| hex = '%032x' % self.int |
| return '%s-%s-%s-%s-%s' % ( |
| hex[:8], hex[8:12], hex[12:16], hex[16:20], hex[20:]) |
| |
| @property |
| def bytes(self): |
| return self.int.to_bytes(16, 'big') |
| |
| @property |
| def bytes_le(self): |
| bytes = self.bytes |
| return (bytes[4-1::-1] + bytes[6-1:4-1:-1] + bytes[8-1:6-1:-1] + |
| bytes[8:]) |
| |
| @property |
| def fields(self): |
| return (self.time_low, self.time_mid, self.time_hi_version, |
| self.clock_seq_hi_variant, self.clock_seq_low, self.node) |
| |
| @property |
| def time_low(self): |
| return self.int >> 96 |
| |
| @property |
| def time_mid(self): |
| return (self.int >> 80) & 0xffff |
| |
| @property |
| def time_hi_version(self): |
| return (self.int >> 64) & 0xffff |
| |
| @property |
| def clock_seq_hi_variant(self): |
| return (self.int >> 56) & 0xff |
| |
| @property |
| def clock_seq_low(self): |
| return (self.int >> 48) & 0xff |
| |
| @property |
| def time(self): |
| return (((self.time_hi_version & 0x0fff) << 48) | |
| (self.time_mid << 32) | self.time_low) |
| |
| @property |
| def clock_seq(self): |
| return (((self.clock_seq_hi_variant & 0x3f) << 8) | |
| self.clock_seq_low) |
| |
| @property |
| def node(self): |
| return self.int & 0xffffffffffff |
| |
| @property |
| def hex(self): |
| return '%032x' % self.int |
| |
| @property |
| def urn(self): |
| return 'urn:uuid:' + str(self) |
| |
| @property |
| def variant(self): |
| if not self.int & (0x8000 << 48): |
| return RESERVED_NCS |
| elif not self.int & (0x4000 << 48): |
| return RFC_4122 |
| elif not self.int & (0x2000 << 48): |
| return RESERVED_MICROSOFT |
| else: |
| return RESERVED_FUTURE |
| |
| @property |
| def version(self): |
| # The version bits are only meaningful for RFC 4122 UUIDs. |
| if self.variant == RFC_4122: |
| return int((self.int >> 76) & 0xf) |
| |
| |
| def _get_command_stdout(command, *args): |
| import io, os, shutil, subprocess |
| |
| try: |
| path_dirs = os.environ.get('PATH', os.defpath).split(os.pathsep) |
| path_dirs.extend(['/sbin', '/usr/sbin']) |
| executable = shutil.which(command, path=os.pathsep.join(path_dirs)) |
| if executable is None: |
| return None |
| # LC_ALL=C to ensure English output, stderr=DEVNULL to prevent output |
| # on stderr (Note: we don't have an example where the words we search |
| # for are actually localized, but in theory some system could do so.) |
| env = dict(os.environ) |
| env['LC_ALL'] = 'C' |
| proc = subprocess.Popen((executable,) + args, |
| stdout=subprocess.PIPE, |
| stderr=subprocess.DEVNULL, |
| env=env) |
| if not proc: |
| return None |
| stdout, stderr = proc.communicate() |
| return io.BytesIO(stdout) |
| except (OSError, subprocess.SubprocessError): |
| return None |
| |
| |
| # For MAC (a.k.a. IEEE 802, or EUI-48) addresses, the second least significant |
| # bit of the first octet signifies whether the MAC address is universally (0) |
| # or locally (1) administered. Network cards from hardware manufacturers will |
| # always be universally administered to guarantee global uniqueness of the MAC |
| # address, but any particular machine may have other interfaces which are |
| # locally administered. An example of the latter is the bridge interface to |
| # the Touch Bar on MacBook Pros. |
| # |
| # This bit works out to be the 42nd bit counting from 1 being the least |
| # significant, or 1<<41. We'll prefer universally administered MAC addresses |
| # over locally administered ones since the former are globally unique, but |
| # we'll return the first of the latter found if that's all the machine has. |
| # |
| # See https://en.wikipedia.org/wiki/MAC_address#Universal_vs._local |
| |
| def _is_universal(mac): |
| return not (mac & (1 << 41)) |
| |
| |
| def _find_mac_near_keyword(command, args, keywords, get_word_index): |
| """Searches a command's output for a MAC address near a keyword. |
| |
| Each line of words in the output is case-insensitively searched for |
| any of the given keywords. Upon a match, get_word_index is invoked |
| to pick a word from the line, given the index of the match. For |
| example, lambda i: 0 would get the first word on the line, while |
| lambda i: i - 1 would get the word preceding the keyword. |
| """ |
| stdout = _get_command_stdout(command, args) |
| if stdout is None: |
| return None |
| |
| first_local_mac = None |
| for line in stdout: |
| words = line.lower().rstrip().split() |
| for i in range(len(words)): |
| if words[i] in keywords: |
| try: |
| word = words[get_word_index(i)] |
| mac = int(word.replace(_MAC_DELIM, b''), 16) |
| except (ValueError, IndexError): |
| # Virtual interfaces, such as those provided by |
| # VPNs, do not have a colon-delimited MAC address |
| # as expected, but a 16-byte HWAddr separated by |
| # dashes. These should be ignored in favor of a |
| # real MAC address |
| pass |
| else: |
| if _is_universal(mac): |
| return mac |
| first_local_mac = first_local_mac or mac |
| return first_local_mac or None |
| |
| |
| def _parse_mac(word): |
| # Accept 'HH:HH:HH:HH:HH:HH' MAC address (ex: '52:54:00:9d:0e:67'), |
| # but reject IPv6 address (ex: 'fe80::5054:ff:fe9' or '123:2:3:4:5:6:7:8'). |
| # |
| # Virtual interfaces, such as those provided by VPNs, do not have a |
| # colon-delimited MAC address as expected, but a 16-byte HWAddr separated |
| # by dashes. These should be ignored in favor of a real MAC address |
| parts = word.split(_MAC_DELIM) |
| if len(parts) != 6: |
| return |
| if _MAC_OMITS_LEADING_ZEROES: |
| # (Only) on AIX the macaddr value given is not prefixed by 0, e.g. |
| # en0 1500 link#2 fa.bc.de.f7.62.4 110854824 0 160133733 0 0 |
| # not |
| # en0 1500 link#2 fa.bc.de.f7.62.04 110854824 0 160133733 0 0 |
| if not all(1 <= len(part) <= 2 for part in parts): |
| return |
| hexstr = b''.join(part.rjust(2, b'0') for part in parts) |
| else: |
| if not all(len(part) == 2 for part in parts): |
| return |
| hexstr = b''.join(parts) |
| try: |
| return int(hexstr, 16) |
| except ValueError: |
| return |
| |
| |
| def _find_mac_under_heading(command, args, heading): |
| """Looks for a MAC address under a heading in a command's output. |
| |
| The first line of words in the output is searched for the given |
| heading. Words at the same word index as the heading in subsequent |
| lines are then examined to see if they look like MAC addresses. |
| """ |
| stdout = _get_command_stdout(command, args) |
| if stdout is None: |
| return None |
| |
| keywords = stdout.readline().rstrip().split() |
| try: |
| column_index = keywords.index(heading) |
| except ValueError: |
| return None |
| |
| first_local_mac = None |
| for line in stdout: |
| words = line.rstrip().split() |
| try: |
| word = words[column_index] |
| except IndexError: |
| continue |
| |
| mac = _parse_mac(word) |
| if mac is None: |
| continue |
| if _is_universal(mac): |
| return mac |
| if first_local_mac is None: |
| first_local_mac = mac |
| |
| return first_local_mac |
| |
| |
| # The following functions call external programs to 'get' a macaddr value to |
| # be used as basis for an uuid |
| def _ifconfig_getnode(): |
| """Get the hardware address on Unix by running ifconfig.""" |
| # This works on Linux ('' or '-a'), Tru64 ('-av'), but not all Unixes. |
| keywords = (b'hwaddr', b'ether', b'address:', b'lladdr') |
| for args in ('', '-a', '-av'): |
| mac = _find_mac_near_keyword('ifconfig', args, keywords, lambda i: i+1) |
| if mac: |
| return mac |
| return None |
| |
| def _ip_getnode(): |
| """Get the hardware address on Unix by running ip.""" |
| # This works on Linux with iproute2. |
| mac = _find_mac_near_keyword('ip', 'link', [b'link/ether'], lambda i: i+1) |
| if mac: |
| return mac |
| return None |
| |
| def _arp_getnode(): |
| """Get the hardware address on Unix by running arp.""" |
| import os, socket |
| try: |
| ip_addr = socket.gethostbyname(socket.gethostname()) |
| except OSError: |
| return None |
| |
| # Try getting the MAC addr from arp based on our IP address (Solaris). |
| mac = _find_mac_near_keyword('arp', '-an', [os.fsencode(ip_addr)], lambda i: -1) |
| if mac: |
| return mac |
| |
| # This works on OpenBSD |
| mac = _find_mac_near_keyword('arp', '-an', [os.fsencode(ip_addr)], lambda i: i+1) |
| if mac: |
| return mac |
| |
| # This works on Linux, FreeBSD and NetBSD |
| mac = _find_mac_near_keyword('arp', '-an', [os.fsencode('(%s)' % ip_addr)], |
| lambda i: i+2) |
| # Return None instead of 0. |
| if mac: |
| return mac |
| return None |
| |
| def _lanscan_getnode(): |
| """Get the hardware address on Unix by running lanscan.""" |
| # This might work on HP-UX. |
| return _find_mac_near_keyword('lanscan', '-ai', [b'lan0'], lambda i: 0) |
| |
| def _netstat_getnode(): |
| """Get the hardware address on Unix by running netstat.""" |
| # This works on AIX and might work on Tru64 UNIX. |
| return _find_mac_under_heading('netstat', '-ian', b'Address') |
| |
| def _ipconfig_getnode(): |
| """[DEPRECATED] Get the hardware address on Windows.""" |
| # bpo-40501: UuidCreateSequential() is now the only supported approach |
| return _windll_getnode() |
| |
| def _netbios_getnode(): |
| """[DEPRECATED] Get the hardware address on Windows.""" |
| # bpo-40501: UuidCreateSequential() is now the only supported approach |
| return _windll_getnode() |
| |
| |
| # Import optional C extension at toplevel, to help disabling it when testing |
| try: |
| import _uuid |
| _generate_time_safe = getattr(_uuid, "generate_time_safe", None) |
| _UuidCreate = getattr(_uuid, "UuidCreate", None) |
| _has_uuid_generate_time_safe = _uuid.has_uuid_generate_time_safe |
| except ImportError: |
| _uuid = None |
| _generate_time_safe = None |
| _UuidCreate = None |
| _has_uuid_generate_time_safe = None |
| |
| |
| def _load_system_functions(): |
| """[DEPRECATED] Platform-specific functions loaded at import time""" |
| |
| |
| def _unix_getnode(): |
| """Get the hardware address on Unix using the _uuid extension module.""" |
| if _generate_time_safe: |
| uuid_time, _ = _generate_time_safe() |
| return UUID(bytes=uuid_time).node |
| |
| def _windll_getnode(): |
| """Get the hardware address on Windows using the _uuid extension module.""" |
| if _UuidCreate: |
| uuid_bytes = _UuidCreate() |
| return UUID(bytes_le=uuid_bytes).node |
| |
| def _random_getnode(): |
| """Get a random node ID.""" |
| # RFC 4122, $4.1.6 says "For systems with no IEEE address, a randomly or |
| # pseudo-randomly generated value may be used; see Section 4.5. The |
| # multicast bit must be set in such addresses, in order that they will |
| # never conflict with addresses obtained from network cards." |
| # |
| # The "multicast bit" of a MAC address is defined to be "the least |
| # significant bit of the first octet". This works out to be the 41st bit |
| # counting from 1 being the least significant bit, or 1<<40. |
| # |
| # See https://en.wikipedia.org/wiki/MAC_address#Unicast_vs._multicast |
| import random |
| return random.getrandbits(48) | (1 << 40) |
| |
| |
| # _OS_GETTERS, when known, are targeted for a specific OS or platform. |
| # The order is by 'common practice' on the specified platform. |
| # Note: 'posix' and 'windows' _OS_GETTERS are prefixed by a dll/dlload() method |
| # which, when successful, means none of these "external" methods are called. |
| # _GETTERS is (also) used by test_uuid.py to SkipUnless(), e.g., |
| # @unittest.skipUnless(_uuid._ifconfig_getnode in _uuid._GETTERS, ...) |
| if _LINUX: |
| _OS_GETTERS = [_ip_getnode, _ifconfig_getnode] |
| elif sys.platform == 'darwin': |
| _OS_GETTERS = [_ifconfig_getnode, _arp_getnode, _netstat_getnode] |
| elif sys.platform == 'win32': |
| # bpo-40201: _windll_getnode will always succeed, so these are not needed |
| _OS_GETTERS = [] |
| elif _AIX: |
| _OS_GETTERS = [_netstat_getnode] |
| else: |
| _OS_GETTERS = [_ifconfig_getnode, _ip_getnode, _arp_getnode, |
| _netstat_getnode, _lanscan_getnode] |
| if os.name == 'posix': |
| _GETTERS = [_unix_getnode] + _OS_GETTERS |
| elif os.name == 'nt': |
| _GETTERS = [_windll_getnode] + _OS_GETTERS |
| else: |
| _GETTERS = _OS_GETTERS |
| |
| _node = None |
| |
| def getnode(): |
| """Get the hardware address as a 48-bit positive integer. |
| |
| The first time this runs, it may launch a separate program, which could |
| be quite slow. If all attempts to obtain the hardware address fail, we |
| choose a random 48-bit number with its eighth bit set to 1 as recommended |
| in RFC 4122. |
| """ |
| global _node |
| if _node is not None: |
| return _node |
| |
| for getter in _GETTERS + [_random_getnode]: |
| try: |
| _node = getter() |
| except: |
| continue |
| if (_node is not None) and (0 <= _node < (1 << 48)): |
| return _node |
| assert False, '_random_getnode() returned invalid value: {}'.format(_node) |
| |
| |
| _last_timestamp = None |
| |
| def uuid1(node=None, clock_seq=None): |
| """Generate a UUID from a host ID, sequence number, and the current time. |
| If 'node' is not given, getnode() is used to obtain the hardware |
| address. If 'clock_seq' is given, it is used as the sequence number; |
| otherwise a random 14-bit sequence number is chosen.""" |
| |
| # When the system provides a version-1 UUID generator, use it (but don't |
| # use UuidCreate here because its UUIDs don't conform to RFC 4122). |
| if _generate_time_safe is not None and node is clock_seq is None: |
| uuid_time, safely_generated = _generate_time_safe() |
| try: |
| is_safe = SafeUUID(safely_generated) |
| except ValueError: |
| is_safe = SafeUUID.unknown |
| return UUID(bytes=uuid_time, is_safe=is_safe) |
| |
| global _last_timestamp |
| import time |
| nanoseconds = time.time_ns() |
| # 0x01b21dd213814000 is the number of 100-ns intervals between the |
| # UUID epoch 1582-10-15 00:00:00 and the Unix epoch 1970-01-01 00:00:00. |
| timestamp = nanoseconds // 100 + 0x01b21dd213814000 |
| if _last_timestamp is not None and timestamp <= _last_timestamp: |
| timestamp = _last_timestamp + 1 |
| _last_timestamp = timestamp |
| if clock_seq is None: |
| import random |
| clock_seq = random.getrandbits(14) # instead of stable storage |
| time_low = timestamp & 0xffffffff |
| time_mid = (timestamp >> 32) & 0xffff |
| time_hi_version = (timestamp >> 48) & 0x0fff |
| clock_seq_low = clock_seq & 0xff |
| clock_seq_hi_variant = (clock_seq >> 8) & 0x3f |
| if node is None: |
| node = getnode() |
| return UUID(fields=(time_low, time_mid, time_hi_version, |
| clock_seq_hi_variant, clock_seq_low, node), version=1) |
| |
| def uuid3(namespace, name): |
| """Generate a UUID from the MD5 hash of a namespace UUID and a name.""" |
| from hashlib import md5 |
| digest = md5( |
| namespace.bytes + bytes(name, "utf-8"), |
| usedforsecurity=False |
| ).digest() |
| return UUID(bytes=digest[:16], version=3) |
| |
| def uuid4(): |
| """Generate a random UUID.""" |
| return UUID(bytes=os.urandom(16), version=4) |
| |
| def uuid5(namespace, name): |
| """Generate a UUID from the SHA-1 hash of a namespace UUID and a name.""" |
| from hashlib import sha1 |
| hash = sha1(namespace.bytes + bytes(name, "utf-8")).digest() |
| return UUID(bytes=hash[:16], version=5) |
| |
| # The following standard UUIDs are for use with uuid3() or uuid5(). |
| |
| NAMESPACE_DNS = UUID('6ba7b810-9dad-11d1-80b4-00c04fd430c8') |
| NAMESPACE_URL = UUID('6ba7b811-9dad-11d1-80b4-00c04fd430c8') |
| NAMESPACE_OID = UUID('6ba7b812-9dad-11d1-80b4-00c04fd430c8') |
| NAMESPACE_X500 = UUID('6ba7b814-9dad-11d1-80b4-00c04fd430c8') |
