import logging import re from .errors import TransportError, ErrorInvalidSchemaVersionForMailboxVersion, ErrorInvalidServerVersion, \ ErrorIncorrectSchemaVersion, ResponseMessageError from .util import xml_to_str, TNS log = logging.getLogger(__name__) # Legend for dict: # Key: shortname # Values: (EWS API version ID, full name) # 'shortname' comes from types.xsd and is the official version of the server, corresponding to the version numbers # supplied in SOAP headers. 'API version' is the version name supplied in the RequestServerVersion element in SOAP # headers and describes the EWS API version the server implements. Valid values for this element are described here: # https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/requestserverversion VERSIONS = { 'Exchange2007': ('Exchange2007', 'Microsoft Exchange Server 2007'), 'Exchange2007_SP1': ('Exchange2007_SP1', 'Microsoft Exchange Server 2007 SP1'), 'Exchange2007_SP2': ('Exchange2007_SP1', 'Microsoft Exchange Server 2007 SP2'), 'Exchange2007_SP3': ('Exchange2007_SP1', 'Microsoft Exchange Server 2007 SP3'), 'Exchange2010': ('Exchange2010', 'Microsoft Exchange Server 2010'), 'Exchange2010_SP1': ('Exchange2010_SP1', 'Microsoft Exchange Server 2010 SP1'), 'Exchange2010_SP2': ('Exchange2010_SP2', 'Microsoft Exchange Server 2010 SP2'), 'Exchange2010_SP3': ('Exchange2010_SP2', 'Microsoft Exchange Server 2010 SP3'), 'Exchange2013': ('Exchange2013', 'Microsoft Exchange Server 2013'), 'Exchange2013_SP1': ('Exchange2013_SP1', 'Microsoft Exchange Server 2013 SP1'), 'Exchange2015': ('Exchange2015', 'Microsoft Exchange Server 2015'), 'Exchange2015_SP1': ('Exchange2015_SP1', 'Microsoft Exchange Server 2015 SP1'), 'Exchange2016': ('Exchange2016', 'Microsoft Exchange Server 2016'), 'Exchange2019': ('Exchange2019', 'Microsoft Exchange Server 2019'), } # Build a list of unique API versions, used when guessing API version supported by the server. Use reverse order so we # get the newest API version supported by the server. API_VERSIONS = sorted({v[0] for v in VERSIONS.values()}, reverse=True) class Build: """ Holds methods for working with build numbers """ # List of build numbers here: https://docs.microsoft.com/en-us/exchange/new-features/build-numbers-and-release-dates API_VERSION_MAP = { 8: { 0: 'Exchange2007', 1: 'Exchange2007_SP1', 2: 'Exchange2007_SP1', 3: 'Exchange2007_SP1', }, 14: { 0: 'Exchange2010', 1: 'Exchange2010_SP1', 2: 'Exchange2010_SP2', 3: 'Exchange2010_SP2', }, 15: { 0: 'Exchange2013', # Minor builds starting from 847 are Exchange2013_SP1, see api_version() 1: 'Exchange2016', 2: 'Exchange2019', 20: 'Exchange2016', # This is Office365. See issue #221 }, } __slots__ = ('major_version', 'minor_version', 'major_build', 'minor_build') def __init__(self, major_version, minor_version, major_build=0, minor_build=0): if not isinstance(major_version, int): raise ValueError("'major_version' must be an integer") if not isinstance(minor_version, int): raise ValueError("'minor_version' must be an integer") if not isinstance(major_build, int): raise ValueError("'major_build' must be an integer") if not isinstance(minor_build, int): raise ValueError("'minor_build' must be an integer") self.major_version = major_version self.minor_version = minor_version self.major_build = major_build self.minor_build = minor_build if major_version < 8: raise ValueError("Exchange major versions below 8 don't support EWS (%s)" % self) @classmethod def from_xml(cls, elem): xml_elems_map = { 'major_version': 'MajorVersion', 'minor_version': 'MinorVersion', 'major_build': 'MajorBuildNumber', 'minor_build': 'MinorBuildNumber', } kwargs = {} for k, xml_elem in xml_elems_map.items(): v = elem.get(xml_elem) if v is None: raise ValueError() kwargs[k] = int(v) # Also raises ValueError return cls(**kwargs) @classmethod def from_hex_string(cls, s): """Parse a server version string as returned in an autodiscover response. The process is described here: https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/serverversion-pox#example The string is a hex string that, converted to a 32-bit binary, encodes the server version. The rules are: * The first 4 bits contain the version number structure version. Can be ignored * The next 6 bits contain the major version number * The next 6 bits contain the minor version number * The next bit contains a flag. Can be ignored * The next 15 bits contain the major build number """ bin_s = '{:032b}'.format(int(s, 16)) # Convert string to 32-bit binary string major_version = int(bin_s[4:10], 2) minor_version = int(bin_s[10:16], 2) build_number = int(bin_s[17:32], 2) return cls(major_version=major_version, minor_version=minor_version, major_build=build_number) def api_version(self): if EXCHANGE_2013_SP1 <= self < EXCHANGE_2016: return 'Exchange2013_SP1' try: return self.API_VERSION_MAP[self.major_version][self.minor_version] except KeyError: raise ValueError('API version for build %s is unknown' % self) def __cmp__(self, other): # __cmp__ is not a magic method in Python3. We'll just use it here to implement comparison operators c = (self.major_version > other.major_version) - (self.major_version < other.major_version) if c != 0: return c c = (self.minor_version > other.minor_version) - (self.minor_version < other.minor_version) if c != 0: return c c = (self.major_build > other.major_build) - (self.major_build < other.major_build) if c != 0: return c return (self.minor_build > other.minor_build) - (self.minor_build < other.minor_build) def __eq__(self, other): return self.__cmp__(other) == 0 def __hash__(self): return hash(repr(self)) def __ne__(self, other): return self.__cmp__(other) != 0 def __lt__(self, other): return self.__cmp__(other) < 0 def __le__(self, other): return self.__cmp__(other) <= 0 def __gt__(self, other): return self.__cmp__(other) > 0 def __ge__(self, other): return self.__cmp__(other) >= 0 def __str__(self): return '%s.%s.%s.%s' % (self.major_version, self.minor_version, self.major_build, self.minor_build) def __repr__(self): return self.__class__.__name__ \ + repr((self.major_version, self.minor_version, self.major_build, self.minor_build)) # Helpers for comparison operations elsewhere in this package EXCHANGE_2007 = Build(8, 0) EXCHANGE_2007_SP1 = Build(8, 1) EXCHANGE_2010 = Build(14, 0) EXCHANGE_2010_SP1 = Build(14, 1) EXCHANGE_2010_SP2 = Build(14, 2) EXCHANGE_2013 = Build(15, 0) EXCHANGE_2013_SP1 = Build(15, 0, 847) EXCHANGE_2016 = Build(15, 1) EXCHANGE_2019 = Build(15, 2) EXCHANGE_O365 = Build(15, 20) class Version: """ Holds information about the server version """ __slots__ = ('build', 'api_version') def __init__(self, build, api_version=None): if not isinstance(build, (Build, type(None))): raise ValueError("'build' must be a Build instance") self.build = build if api_version is None: self.api_version = build.api_version() else: if not isinstance(api_version, str): raise ValueError("'api_version' must be a string") self.api_version = api_version @property def fullname(self): return VERSIONS[self.api_version][1] @classmethod def guess(cls, protocol, api_version_hint=None): """ Tries to ask the server which version it has. We haven't set up an Account object yet, so we generate requests by hand. We only need a response header containing a ServerVersionInfo element. To get API version and build numbers from the server, we need to send a valid SOAP request. We can't do that without a valid API version. To solve this chicken-and-egg problem, we try all possible API versions that this package supports, until we get a valid response. """ from .services import ResolveNames # The protocol doesn't have a version yet, so default to latest supported version if we don't have a hint. api_version = api_version_hint or API_VERSIONS[0] log.debug('Asking server for version info using API version %s', api_version) # We don't know the build version yet. Hopefully, the server will report it in the SOAP header. Lots of # places expect a version to have a build, so this is a bit dangerous, but passing a fake build around is also # dangerous. Make sure the call to ResolveNames does not require a version build. protocol.config.version = Version(build=None, api_version=api_version) # Use ResolveNames as a minimal request to the server to test if the version is correct. If not, ResolveNames # will try to guess the version automatically. name = str(protocol.credentials) if protocol.credentials and str(protocol.credentials) else 'DUMMY' try: list(ResolveNames(protocol=protocol).call(unresolved_entries=[name])) except (ErrorInvalidSchemaVersionForMailboxVersion, ErrorInvalidServerVersion, ErrorIncorrectSchemaVersion): raise TransportError('Unable to guess version') except ResponseMessageError: # We survived long enough to get a new version pass if not protocol.version.build: raise AttributeError('Protocol should have a build number at this point') return protocol.version @staticmethod def _is_invalid_version_string(version): # Check if a version string is bogus, e.g. V2_, V2015_ or V2018_ return re.match(r'V[0-9]{1,4}_.*', version) @classmethod def from_soap_header(cls, requested_api_version, header): info = header.find('{%s}ServerVersionInfo' % TNS) if info is None: raise TransportError('No ServerVersionInfo in header: %r' % xml_to_str(header)) try: build = Build.from_xml(elem=info) except ValueError: raise TransportError('Bad ServerVersionInfo in response: %r' % xml_to_str(header)) # Not all Exchange servers send the Version element api_version_from_server = info.get('Version') or build.api_version() if api_version_from_server != requested_api_version: if cls._is_invalid_version_string(api_version_from_server): # For unknown reasons, Office 365 may respond with an API version strings that is invalid in a request. # Detect these so we can fallback to a valid version string. log.debug('API version "%s" worked but server reports version "%s". Using "%s"', requested_api_version, api_version_from_server, requested_api_version) api_version_from_server = requested_api_version else: # Trust API version from server response log.debug('API version "%s" worked but server reports version "%s". Using "%s"', requested_api_version, api_version_from_server, api_version_from_server) return cls(build=build, api_version=api_version_from_server) def __eq__(self, other): if self.api_version != other.api_version: return False if self.build and not other.build: return False if other.build and not self.build: return False return self.build == other.build def __repr__(self): return self.__class__.__name__ + repr((self.build, self.api_version)) def __str__(self): return 'Build=%s, API=%s, Fullname=%s' % (self.build, self.api_version, self.fullname)