JezK
Edit File: core.py
# -*- coding: utf-8 -*- from __future__ import absolute_import, print_function, unicode_literals import re import os import warnings import weakref from . import gpgme from .errors import errorcheck, GPGMEError from . import constants from . import errors from . import util del absolute_import, print_function, unicode_literals # Copyright (C) 2016-2018 g10 Code GmbH # Copyright (C) 2004, 2008 Igor Belyi <belyi@users.sourceforge.net> # Copyright (C) 2002 John Goerzen <jgoerzen@complete.org> # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public # License as published by the Free Software Foundation; either # version 2.1 of the License, or (at your option) any later version. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public # License along with this library; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA """Core functionality Core functionality of GPGME wrapped in a object-oriented fashion. Provides the 'Context' class for performing cryptographic operations, and the 'Data' class describing buffers of data. """ class GpgmeWrapper(object): """Base wrapper class Not to be instantiated directly. """ def __init__(self, wrapped): self._callback_excinfo = None self.wrapped = wrapped def __repr__(self): return '<{}/{!r}>'.format( super(GpgmeWrapper, self).__repr__(), self.wrapped) def __str__(self): acc = ['{}.{}'.format(__name__, self.__class__.__name__)] flags = [f for f in self._boolean_properties if getattr(self, f)] if flags: acc.append('({})'.format(' '.join(flags))) return '<{}>'.format(' '.join(acc)) def __hash__(self): return hash(repr(self.wrapped)) def __eq__(self, other): if other is None: return False else: return repr(self.wrapped) == repr(other.wrapped) @property def _ctype(self): """The name of the c type wrapped by this class Must be set by child classes. """ raise NotImplementedError() @property def _cprefix(self): """The common prefix of c functions wrapped by this class Must be set by child classes. """ raise NotImplementedError() def _errorcheck(self, name): """Must be implemented by child classes. This function must return a trueish value for all c functions returning gpgme_error_t.""" raise NotImplementedError() """The set of all boolean properties""" _boolean_properties = set() def __wrap_boolean_property(self, key, do_set=False, value=None): get_func = getattr(gpgme, "{}get_{}".format(self._cprefix, key)) set_func = getattr(gpgme, "{}set_{}".format(self._cprefix, key)) def get(slf): if not slf.wrapped: return False return bool(get_func(slf.wrapped)) def set_(slf, value): if not slf.wrapped: return set_func(slf.wrapped, bool(value)) p = property(get, set_, doc="{} flag".format(key)) setattr(self.__class__, key, p) if do_set: set_(self, bool(value)) else: return get(self) _munge_docstring = re.compile(r'gpgme_([^(]*)\(([^,]*), (.*\) -> .*)') def __getattr__(self, key): """On-the-fly generation of wrapper methods and properties""" if key[0] == '_' or self._cprefix is None: return None if key in self._boolean_properties: return self.__wrap_boolean_property(key) name = self._cprefix + key func = getattr(gpgme, name) if self._errorcheck(name): def _funcwrap(slf, *args): if not slf.wrapped: return None result = func(slf.wrapped, *args) if slf._callback_excinfo: gpgme.gpg_raise_callback_exception(slf) return errorcheck(result, name) else: def _funcwrap(slf, *args): if not slf.wrapped: return None result = func(slf.wrapped, *args) if slf._callback_excinfo: gpgme.gpg_raise_callback_exception(slf) return result doc_orig = getattr(func, "__doc__") if doc_orig: doc = self._munge_docstring.sub(r'\2.\1(\3', doc_orig) else: doc = None _funcwrap.__doc__ = doc # Monkey-patch the class. setattr(self.__class__, key, _funcwrap) # Bind the method to 'self'. def wrapper(*args): return _funcwrap(self, *args) wrapper.__doc__ = doc return wrapper def __setattr__(self, key, value): """On-the-fly generation of properties""" if key in self._boolean_properties: self.__wrap_boolean_property(key, True, value) else: super(GpgmeWrapper, self).__setattr__(key, value) class Context(GpgmeWrapper): """Context for cryptographic operations All cryptographic operations in GPGME are performed within a context, which contains the internal state of the operation as well as configuration parameters. By using several contexts you can run several cryptographic operations in parallel, with different configuration. Access to a context must be synchronized. """ def __init__(self, armor=False, textmode=False, offline=False, signers=[], pinentry_mode=constants.PINENTRY_MODE_DEFAULT, protocol=constants.PROTOCOL_OpenPGP, wrapped=None, home_dir=None): """Construct a context object Keyword arguments: armor -- enable ASCII armoring (default False) textmode -- enable canonical text mode (default False) offline -- do not contact external key sources (default False) signers -- list of keys used for signing (default []) pinentry_mode -- pinentry mode (default PINENTRY_MODE_DEFAULT) protocol -- protocol to use (default PROTOCOL_OpenPGP) home_dir -- state directory (default is the engine default) """ if wrapped: self.own = False else: tmp = gpgme.new_gpgme_ctx_t_p() errorcheck(gpgme.gpgme_new(tmp)) wrapped = gpgme.gpgme_ctx_t_p_value(tmp) gpgme.delete_gpgme_ctx_t_p(tmp) self.own = True super(Context, self).__init__(wrapped) self.armor = armor self.textmode = textmode self.offline = offline self.signers = signers self.pinentry_mode = pinentry_mode self.protocol = protocol self.home_dir = home_dir def __read__(self, sink, data): """Read helper Helper function to retrieve the results of an operation, or None if SINK is given. """ if sink or data is None: return None data.seek(0, os.SEEK_SET) return data.read() def __repr__(self): return ("Context(armor={0.armor}, " "textmode={0.textmode}, offline={0.offline}, " "signers={0.signers}, pinentry_mode={0.pinentry_mode}, " "protocol={0.protocol}, home_dir={0.home_dir}" ")").format(self) def encrypt(self, plaintext, recipients=[], sign=True, sink=None, passphrase=None, always_trust=False, add_encrypt_to=False, prepare=False, expect_sign=False, compress=True): """Encrypt data Encrypt the given plaintext for the given recipients. If the list of recipients is empty, the data is encrypted symmetrically with a passphrase. The passphrase can be given as parameter, using a callback registered at the context, or out-of-band via pinentry. Keyword arguments: recipients -- list of keys to encrypt to sign -- sign plaintext (default True) sink -- write result to sink instead of returning it passphrase -- for symmetric encryption always_trust -- always trust the keys (default False) add_encrypt_to -- encrypt to configured additional keys (default False) prepare -- (ui) prepare for encryption (default False) expect_sign -- (ui) prepare for signing (default False) compress -- compress plaintext (default True) Returns: ciphertext -- the encrypted data (or None if sink is given) result -- additional information about the encryption sign_result -- additional information about the signature(s) Raises: InvalidRecipients -- if encryption using a particular key failed InvalidSigners -- if signing using a particular key failed GPGMEError -- as signaled by the underlying library """ ciphertext = sink if sink else Data() flags = 0 flags |= always_trust * constants.ENCRYPT_ALWAYS_TRUST flags |= (not add_encrypt_to) * constants.ENCRYPT_NO_ENCRYPT_TO flags |= prepare * constants.ENCRYPT_PREPARE flags |= expect_sign * constants.ENCRYPT_EXPECT_SIGN flags |= (not compress) * constants.ENCRYPT_NO_COMPRESS if passphrase is not None: old_pinentry_mode = self.pinentry_mode old_passphrase_cb = getattr(self, '_passphrase_cb', None) self.pinentry_mode = constants.PINENTRY_MODE_LOOPBACK def passphrase_cb(hint, desc, prev_bad, hook=None): return passphrase self.set_passphrase_cb(passphrase_cb) try: if sign: self.op_encrypt_sign(recipients, flags, plaintext, ciphertext) else: self.op_encrypt(recipients, flags, plaintext, ciphertext) except errors.GPGMEError as e: result = self.op_encrypt_result() sig_result = self.op_sign_result() if sign else None results = (self.__read__(sink, ciphertext), result, sig_result) if e.getcode() == errors.UNUSABLE_PUBKEY: if result.invalid_recipients: raise errors.InvalidRecipients( result.invalid_recipients, error=e.error, results=results) if e.getcode() == errors.UNUSABLE_SECKEY: sig_result = self.op_sign_result() if sig_result.invalid_signers: raise errors.InvalidSigners( sig_result.invalid_signers, error=e.error, results=results) # Otherwise, just raise the error, but attach the results # first. e.results = results raise e finally: if passphrase is not None: self.pinentry_mode = old_pinentry_mode gpgme.gpg_set_passphrase_cb(self, old_passphrase_cb) result = self.op_encrypt_result() assert not result.invalid_recipients sig_result = self.op_sign_result() if sign else None assert not sig_result or not sig_result.invalid_signers return self.__read__(sink, ciphertext), result, sig_result def decrypt(self, ciphertext, sink=None, passphrase=None, verify=True, filter_signatures=True): """Decrypt data Decrypt the given ciphertext and verify any signatures. If VERIFY is an iterable of keys, the ciphertext must be signed by all those keys, otherwise a MissingSignatures error is raised. Note: if VERIFY is an empty iterable, that is treated the same as passing verify=True (that is, verify signatures and return data about any valid signatures found, but no signatures are required and no MissingSignatures error will be raised). The filter_signatures argument can be used to force this function to return signatures that are not fully trusted - for example because they were made by unknown keys. If the ciphertext is symmetrically encrypted using a passphrase, that passphrase can be given as parameter, using a callback registered at the context, or out-of-band via pinentry. Keyword arguments: sink -- write result to sink instead of returning it passphrase -- for symmetric decryption verify -- check signatures (boolean or iterable of keys, see above) (default True) filter_signatures -- if this function should filter out signatures that are not completely OK (default True) Returns: plaintext -- the decrypted data (or None if sink is given) result -- additional information about the decryption verify_result -- additional information about the valid signature(s) found Raises: UnsupportedAlgorithm -- if an unsupported algorithm was used MissingSignatures -- if expected signatures are missing or bad GPGMEError -- as signaled by the underlying library """ do_sig_verification = False required_keys = None plaintext = sink if sink else Data() if passphrase is not None: old_pinentry_mode = self.pinentry_mode old_passphrase_cb = getattr(self, '_passphrase_cb', None) self.pinentry_mode = constants.PINENTRY_MODE_LOOPBACK def passphrase_cb(hint, desc, prev_bad, hook=None): return passphrase self.set_passphrase_cb(passphrase_cb) try: if isinstance(verify, bool): do_sig_verification = verify elif verify is None: warnings.warn( "ctx.decrypt called with verify=None, should be bool or iterable (treating as False).", category=DeprecationWarning) do_sig_verification = False else: # we hope this is an iterable: required_keys = verify do_sig_verification = True if do_sig_verification: self.op_decrypt_verify(ciphertext, plaintext) else: self.op_decrypt(ciphertext, plaintext) except errors.GPGMEError as e: result = self.op_decrypt_result() if do_sig_verification: verify_result = self.op_verify_result() else: verify_result = None # Just raise the error, but attach the results first. e.results = (self.__read__(sink, plaintext), result, verify_result) raise e finally: if passphrase is not None: self.pinentry_mode = old_pinentry_mode gpgme.gpg_set_passphrase_cb(self, old_passphrase_cb) result = self.op_decrypt_result() if do_sig_verification: verify_result = self.op_verify_result() else: verify_result = None results = (self.__read__(sink, plaintext), result, verify_result) if result.unsupported_algorithm: raise errors.UnsupportedAlgorithm(result.unsupported_algorithm, results=results) if do_sig_verification: if filter_signatures: verify_result.signatures = list(filter(lambda s: s.status == errors.NO_ERROR, verify_result.signatures)) if required_keys is not None: missing = [] for key in required_keys: ok = False for subkey in key.subkeys: for sig in verify_result.signatures: if sig.summary & constants.SIGSUM_VALID == 0: continue if subkey.can_sign and subkey.fpr == sig.fpr: ok = True break if ok: break if not ok: missing.append(key) if missing: raise errors.MissingSignatures(verify_result, missing, results=results) return results def sign(self, data, sink=None, mode=constants.SIG_MODE_NORMAL): """Sign data Sign the given data with either the configured default local key, or the 'signers' keys of this context. Keyword arguments: mode -- signature mode (default: normal, see below) sink -- write result to sink instead of returning it Returns: either signed_data -- encoded data and signature (normal mode) signature -- only the signature data (detached mode) cleartext -- data and signature as text (cleartext mode) (or None if sink is given) result -- additional information about the signature(s) Raises: InvalidSigners -- if signing using a particular key failed GPGMEError -- as signaled by the underlying library """ signeddata = sink if sink else Data() try: self.op_sign(data, signeddata, mode) except errors.GPGMEError as e: results = (self.__read__(sink, signeddata), self.op_sign_result()) if e.getcode() == errors.UNUSABLE_SECKEY: if results[1].invalid_signers: raise errors.InvalidSigners( results[1].invalid_signers, error=e.error, results=results) e.results = results raise e result = self.op_sign_result() assert not result.invalid_signers return self.__read__(sink, signeddata), result def verify(self, signed_data, signature=None, sink=None, verify=[]): """Verify signatures Verify signatures over data. If VERIFY is an iterable of keys, the ciphertext must be signed by all those keys, otherwise an error is raised. Keyword arguments: signature -- detached signature data sink -- write result to sink instead of returning it Returns: data -- the plain data (or None if sink is given, or we verified a detached signature) result -- additional information about the signature(s) Raises: BadSignatures -- if a bad signature is encountered MissingSignatures -- if expected signatures are missing or bad GPGMEError -- as signaled by the underlying library """ if signature: # Detached signature, we don't return the plain text. data = None else: data = sink if sink else Data() try: if signature: self.op_verify(signature, signed_data, None) else: self.op_verify(signed_data, None, data) except errors.GPGMEError as e: # Just raise the error, but attach the results first. e.results = (self.__read__(sink, data), self.op_verify_result()) raise e results = (self.__read__(sink, data), self.op_verify_result()) if any(s.status != errors.NO_ERROR for s in results[1].signatures): raise errors.BadSignatures(results[1], results=results) missing = list() for key in verify: ok = False for subkey in key.subkeys: for sig in results[1].signatures: if sig.summary & constants.SIGSUM_VALID == 0: continue if subkey.can_sign and subkey.fpr == sig.fpr: ok = True break if ok: break if not ok: missing.append(key) if missing: raise errors.MissingSignatures( results[1], missing, results=results) return results def key_import(self, data): """Import data Imports the given data into the Context. Returns: -- an object describing the results of imported or updated keys Raises: TypeError -- Very rarely. GPGMEError -- as signaled by the underlying library: Import status errors, when they occur, will usually be of NODATA. NO_PUBKEY indicates something managed to run the function without any arguments, while an argument of None triggers the first NODATA of errors.GPGME in the exception. """ try: self.op_import(data) result = self.op_import_result() if result.considered == 0: status = constants.STATUS_IMPORT_PROBLEM else: status = constants.STATUS_KEY_CONSIDERED except Exception as e: if e == errors.GPGMEError: if e.code_str == "No data": status = constants.STATUS_NODATA else: status = constants.STATUS_FILE_ERROR elif e == TypeError and hasattr(data, "decode") is True: status = constants.STATUS_NO_PUBKEY elif e == TypeError and hasattr(data, "encode") is True: status = constants.STATUS_FILE_ERROR else: status = constants.STATUS_ERROR if status == constants.STATUS_KEY_CONSIDERED: import_result = result else: import_result = status return import_result def key_export(self, pattern=None): """Export keys. Exports public keys matching the pattern specified. If no pattern is specified then exports all available keys. Keyword arguments: pattern -- return keys matching pattern (default: all keys) Returns: -- A key block containing one or more OpenPGP keys in either ASCII armoured or binary format as determined by the Context(). If there are no matching keys it returns None. Raises: GPGMEError -- as signaled by the underlying library. """ data = Data() mode = 0 try: self.op_export(pattern, mode, data) data.seek(0, os.SEEK_SET) pk_result = data.read() except GPGMEError as e: raise e if len(pk_result) > 0: result = pk_result else: result = None return result def key_export_minimal(self, pattern=None): """Export keys. Exports public keys matching the pattern specified in a minimised format. If no pattern is specified then exports all available keys. Keyword arguments: pattern -- return keys matching pattern (default: all keys) Returns: -- A key block containing one or more minimised OpenPGP keys in either ASCII armoured or binary format as determined by the Context(). If there are no matching keys it returns None. Raises: GPGMEError -- as signaled by the underlying library. """ data = Data() mode = gpgme.GPGME_EXPORT_MODE_MINIMAL try: self.op_export(pattern, mode, data) data.seek(0, os.SEEK_SET) pk_result = data.read() except GPGMEError as e: raise e if len(pk_result) > 0: result = pk_result else: result = None return result def key_export_secret(self, pattern=None): """Export secret keys. Exports secret keys matching the pattern specified. If no pattern is specified then exports or attempts to export all available secret keys. IMPORTANT: Each secret key to be exported will prompt for its passphrase via an invocation of pinentry and gpg-agent. If the passphrase is not entered or does not match then no data will be exported. This is the same result as when specifying a pattern that is not matched by the available keys. Keyword arguments: pattern -- return keys matching pattern (default: all keys) Returns: -- On success a key block containing one or more OpenPGP secret keys in either ASCII armoured or binary format as determined by the Context(). -- On failure while not raising an exception, returns None. Raises: GPGMEError -- as signaled by the underlying library. """ data = Data() mode = gpgme.GPGME_EXPORT_MODE_SECRET try: self.op_export(pattern, mode, data) data.seek(0, os.SEEK_SET) sk_result = data.read() except GPGMEError as e: raise e if len(sk_result) > 0: result = sk_result else: result = None return result def keylist(self, pattern=None, secret=False, mode=constants.keylist.mode.LOCAL, source=None): """List keys Keyword arguments: pattern -- return keys matching pattern (default: all keys) secret -- return only secret keys (default: False) mode -- keylist mode (default: list local keys) source -- read keys from source instead from the keyring (all other options are ignored in this case) Returns: -- an iterator returning key objects Raises: GPGMEError -- as signaled by the underlying library """ if not source: self.set_keylist_mode(mode) self.op_keylist_start(pattern, secret) else: # Automatic wrapping of SOURCE is not possible here, # because the object must not be deallocated until the # iteration over the results ends. if not isinstance(source, Data): source = Data(file=source) self.op_keylist_from_data_start(source, 0) key = self.op_keylist_next() while key: yield key key = self.op_keylist_next() self.op_keylist_end() def create_key(self, userid, algorithm=None, expires_in=0, expires=True, sign=False, encrypt=False, certify=False, authenticate=False, passphrase=None, force=False): """Create a primary key Create a primary key for the user id USERID. ALGORITHM may be used to specify the public key encryption algorithm for the new key. By default, a reasonable default is chosen. You may use "future-default" to select an algorithm that will be the default in a future implementation of the engine. ALGORITHM may be a string like "rsa", or "rsa2048" to explicitly request an algorithm and a key size. EXPIRES_IN specifies the expiration time of the key in number of seconds since the keys creation. By default, a reasonable expiration time is chosen. If you want to create a key that does not expire, use the keyword argument EXPIRES. SIGN, ENCRYPT, CERTIFY, and AUTHENTICATE can be used to request the capabilities of the new key. If you don't request any, a reasonable set of capabilities is selected, and in case of OpenPGP, a subkey with a reasonable set of capabilities is created. If PASSPHRASE is None (the default), then the key will not be protected with a passphrase. If PASSPHRASE is a string, it will be used to protect the key. If PASSPHRASE is True, the passphrase must be supplied using a passphrase callback or out-of-band with a pinentry. Keyword arguments: algorithm -- public key algorithm, see above (default: reasonable) expires_in -- expiration time in seconds (default: reasonable) expires -- whether or not the key should expire (default: True) sign -- request the signing capability (see above) encrypt -- request the encryption capability (see above) certify -- request the certification capability (see above) authenticate -- request the authentication capability (see above) passphrase -- protect the key with a passphrase (default: no passphrase) force -- force key creation even if a key with the same userid exists (default: False) Returns: -- an object describing the result of the key creation Raises: GPGMEError -- as signaled by the underlying library """ if util.is_a_string(passphrase): old_pinentry_mode = self.pinentry_mode old_passphrase_cb = getattr(self, '_passphrase_cb', None) self.pinentry_mode = constants.PINENTRY_MODE_LOOPBACK def passphrase_cb(hint, desc, prev_bad, hook=None): return passphrase self.set_passphrase_cb(passphrase_cb) try: self.op_createkey( userid, algorithm, 0, # reserved expires_in, None, # extrakey ((constants.create.SIGN if sign else 0) | (constants.create.ENCR if encrypt else 0) | (constants.create.CERT if certify else 0) | (constants.create.AUTH if authenticate else 0) | (constants.create.NOPASSWD if passphrase is None else 0) | (0 if expires else constants.create.NOEXPIRE) | (constants.create.FORCE if force else 0))) finally: if util.is_a_string(passphrase): self.pinentry_mode = old_pinentry_mode gpgme.gpg_set_passphrase_cb(self, old_passphrase_cb) return self.op_genkey_result() def create_subkey(self, key, algorithm=None, expires_in=0, expires=True, sign=False, encrypt=False, authenticate=False, passphrase=None): """Create a subkey Create a subkey for the given KEY. As subkeys are a concept of OpenPGP, calling this is only valid for the OpenPGP protocol. ALGORITHM may be used to specify the public key encryption algorithm for the new subkey. By default, a reasonable default is chosen. You may use "future-default" to select an algorithm that will be the default in a future implementation of the engine. ALGORITHM may be a string like "rsa", or "rsa2048" to explicitly request an algorithm and a key size. EXPIRES_IN specifies the expiration time of the subkey in number of seconds since the subkeys creation. By default, a reasonable expiration time is chosen. If you want to create a subkey that does not expire, use the keyword argument EXPIRES. SIGN, ENCRYPT, and AUTHENTICATE can be used to request the capabilities of the new subkey. If you don't request any, an encryption subkey is generated. If PASSPHRASE is None (the default), then the subkey will not be protected with a passphrase. If PASSPHRASE is a string, it will be used to protect the subkey. If PASSPHRASE is True, the passphrase must be supplied using a passphrase callback or out-of-band with a pinentry. Keyword arguments: algorithm -- public key algorithm, see above (default: reasonable) expires_in -- expiration time in seconds (default: reasonable) expires -- whether or not the subkey should expire (default: True) sign -- request the signing capability (see above) encrypt -- request the encryption capability (see above) authenticate -- request the authentication capability (see above) passphrase -- protect the subkey with a passphrase (default: no passphrase) Returns: -- an object describing the result of the subkey creation Raises: GPGMEError -- as signaled by the underlying library """ if util.is_a_string(passphrase): old_pinentry_mode = self.pinentry_mode old_passphrase_cb = getattr(self, '_passphrase_cb', None) self.pinentry_mode = constants.PINENTRY_MODE_LOOPBACK def passphrase_cb(hint, desc, prev_bad, hook=None): return passphrase self.set_passphrase_cb(passphrase_cb) try: self.op_createsubkey( key, algorithm, 0, # reserved expires_in, ((constants.create.SIGN if sign else 0) | (constants.create.ENCR if encrypt else 0) | (constants.create.AUTH if authenticate else 0) | (constants.create.NOPASSWD if passphrase is None else 0) | (0 if expires else constants.create.NOEXPIRE))) finally: if util.is_a_string(passphrase): self.pinentry_mode = old_pinentry_mode gpgme.gpg_set_passphrase_cb(self, old_passphrase_cb) return self.op_genkey_result() def key_add_uid(self, key, uid): """Add a UID Add the uid UID to the given KEY. Calling this function is only valid for the OpenPGP protocol. Raises: GPGMEError -- as signaled by the underlying library """ self.op_adduid(key, uid, 0) def key_revoke_uid(self, key, uid): """Revoke a UID Revoke the uid UID from the given KEY. Calling this function is only valid for the OpenPGP protocol. Raises: GPGMEError -- as signaled by the underlying library """ self.op_revuid(key, uid, 0) def key_sign(self, key, uids=None, expires_in=False, local=False): """Sign a key Sign a key with the current set of signing keys. Calling this function is only valid for the OpenPGP protocol. If UIDS is None (the default), then all UIDs are signed. If it is a string, then only the matching UID is signed. If it is a list of strings, then all matching UIDs are signed. Note that a case-sensitive exact string comparison is done. EXPIRES_IN specifies the expiration time of the signature in seconds. If EXPIRES_IN is False, the signature does not expire. Keyword arguments: uids -- user ids to sign, see above (default: sign all) expires_in -- validity period of the signature in seconds (default: do not expire) local -- create a local, non-exportable signature (default: False) Raises: GPGMEError -- as signaled by the underlying library """ flags = 0 if uids is None or util.is_a_string(uids): pass # through unchanged else: flags |= constants.keysign.LFSEP uids = "\n".join(uids) if not expires_in: flags |= constants.keysign.NOEXPIRE if local: flags |= constants.keysign.LOCAL self.op_keysign(key, uids, expires_in, flags) def key_tofu_policy(self, key, policy): """Set a keys' TOFU policy Set the TOFU policy associated with KEY to POLICY. Calling this function is only valid for the OpenPGP protocol. Raises: GPGMEError -- as signaled by the underlying library """ self.op_tofu_policy(key, policy) def assuan_transact(self, command, data_cb=None, inquire_cb=None, status_cb=None): """Issue a raw assuan command This function can be used to issue a raw assuan command to the engine. If command is a string or bytes, it will be used as-is. If it is an iterable of strings, it will be properly escaped and joined into an well-formed assuan command. Keyword arguments: data_cb -- a callback receiving data lines inquire_cb -- a callback providing more information status_cb -- a callback receiving status lines Returns: result -- the result of command as GPGMEError Raises: GPGMEError -- as signaled by the underlying library """ if util.is_a_string(command) or isinstance(command, bytes): cmd = command else: cmd = " ".join(util.percent_escape(f) for f in command) errptr = gpgme.new_gpgme_error_t_p() err = gpgme.gpgme_op_assuan_transact_ext( self.wrapped, cmd, (weakref.ref(self), data_cb) if data_cb else None, (weakref.ref(self), inquire_cb) if inquire_cb else None, (weakref.ref(self), status_cb) if status_cb else None, errptr) if self._callback_excinfo: gpgme.gpg_raise_callback_exception(self) errorcheck(err) status = gpgme.gpgme_error_t_p_value(errptr) gpgme.delete_gpgme_error_t_p(errptr) return GPGMEError(status) if status != 0 else None def interact(self, key, func, sink=None, flags=0, fnc_value=None): """Interact with the engine This method can be used to edit keys and cards interactively. KEY is the key to edit, FUNC is called repeatedly with two unicode arguments, 'keyword' and 'args'. See the GPGME manual for details. Keyword arguments: sink -- if given, additional output is written here flags -- use constants.INTERACT_CARD to edit a card Raises: GPGMEError -- as signaled by the underlying library """ if key is None: raise ValueError("First argument cannot be None") if sink is None: sink = Data() if fnc_value: opaquedata = (weakref.ref(self), func, fnc_value) else: opaquedata = (weakref.ref(self), func) result = gpgme.gpgme_op_interact(self.wrapped, key, flags, opaquedata, sink) if self._callback_excinfo: gpgme.gpg_raise_callback_exception(self) errorcheck(result) @property def signers(self): """Keys used for signing""" if not self.wrapped: return None return [self.signers_enum(i) for i in range(self.signers_count())] @signers.setter def signers(self, signers): old = self.signers self.signers_clear() try: for key in signers: self.signers_add(key) except: self.signers = old raise @property def pinentry_mode(self): """Pinentry mode""" return self.get_pinentry_mode() @pinentry_mode.setter def pinentry_mode(self, value): self.set_pinentry_mode(value) @property def protocol(self): """Protocol to use""" return self.get_protocol() @protocol.setter def protocol(self, value): errorcheck(gpgme.gpgme_engine_check_version(value)) self.set_protocol(value) @property def home_dir(self): """Engine's home directory""" if not self.wrapped: return None return self.engine_info.home_dir @home_dir.setter def home_dir(self, value): self.set_engine_info(self.protocol, home_dir=value) _ctype = 'gpgme_ctx_t' _cprefix = 'gpgme_' def _errorcheck(self, name): """This function should list all functions returning gpgme_error_t""" # The list of functions is created using: # # $ grep '^gpgme_error_t ' obj/lang/python/python3.5-gpg/gpgme.h \ # | grep -v _op_ | awk "/\(gpgme_ctx/ { printf (\"'%s',\\n\", \$2) } " return ((name.startswith('gpgme_op_') and not name.endswith('_result')) or name in { 'gpgme_new', 'gpgme_set_ctx_flag', 'gpgme_set_protocol', 'gpgme_set_sub_protocol', 'gpgme_set_keylist_mode', 'gpgme_set_pinentry_mode', 'gpgme_set_locale', 'gpgme_ctx_set_engine_info', 'gpgme_signers_add', 'gpgme_sig_notation_add', 'gpgme_set_sender', 'gpgme_cancel', 'gpgme_cancel_async', 'gpgme_get_key', 'gpgme_get_sig_key', }) _boolean_properties = {'armor', 'textmode', 'offline'} def __del__(self): if not gpgme: # At interpreter shutdown, gpgme is set to NONE. return self._free_passcb() self._free_progresscb() self._free_statuscb() if self.own and self.wrapped and gpgme.gpgme_release: gpgme.gpgme_release(self.wrapped) self.wrapped = None # Implement the context manager protocol. def __enter__(self): return self def __exit__(self, type, value, tb): return False def op_keylist_all(self, *args, **kwargs): self.op_keylist_start(*args, **kwargs) key = self.op_keylist_next() while key: yield key key = self.op_keylist_next() self.op_keylist_end() def op_keylist_next(self): """Returns the next key in the list created by a call to op_keylist_start(). The object returned is of type Key.""" ptr = gpgme.new_gpgme_key_t_p() try: errorcheck(gpgme.gpgme_op_keylist_next(self.wrapped, ptr)) key = gpgme.gpgme_key_t_p_value(ptr) except errors.GPGMEError as excp: key = None if excp.getcode() != errors.EOF: raise excp gpgme.delete_gpgme_key_t_p(ptr) if key: key.__del__ = lambda self: gpgme.gpgme_key_unref(self) return key def get_key(self, fpr, secret=False): """Get a key given a fingerprint Keyword arguments: secret -- to request a secret key Returns: -- the matching key Raises: KeyError -- if the key was not found GPGMEError -- as signaled by the underlying library """ ptr = gpgme.new_gpgme_key_t_p() try: errorcheck(gpgme.gpgme_get_key(self.wrapped, fpr, ptr, secret)) except errors.GPGMEError as e: if e.getcode() == errors.EOF: raise errors.KeyNotFound(fpr) raise e key = gpgme.gpgme_key_t_p_value(ptr) gpgme.delete_gpgme_key_t_p(ptr) assert key key.__del__ = lambda self: gpgme.gpgme_key_unref(self) return key def op_trustlist_all(self, *args, **kwargs): self.op_trustlist_start(*args, **kwargs) trust = self.op_trustlist_next() while trust: yield trust trust = self.op_trustlist_next() self.op_trustlist_end() def op_trustlist_next(self): """Returns the next trust item in the list created by a call to op_trustlist_start(). The object returned is of type TrustItem.""" ptr = gpgme.new_gpgme_trust_item_t_p() try: errorcheck(gpgme.gpgme_op_trustlist_next(self.wrapped, ptr)) trust = gpgme.gpgme_trust_item_t_p_value(ptr) except errors.GPGMEError as excp: trust = None if excp.getcode() != errors.EOF: raise gpgme.delete_gpgme_trust_item_t_p(ptr) return trust def set_passphrase_cb(self, func, hook=None): """Sets the passphrase callback to the function specified by func. When the system needs a passphrase, it will call func with three args: hint, a string describing the key it needs the passphrase for; desc, a string describing the passphrase it needs; prev_bad, a boolean equal True if this is a call made after unsuccessful previous attempt. If hook has a value other than None it will be passed into the func as a forth argument. Please see the GPGME manual for more information. """ if func is None: hookdata = None else: if hook is None: hookdata = (weakref.ref(self), func) else: hookdata = (weakref.ref(self), func, hook) gpgme.gpg_set_passphrase_cb(self, hookdata) def _free_passcb(self): if gpgme.gpg_set_passphrase_cb: self.set_passphrase_cb(None) def set_progress_cb(self, func, hook=None): """Sets the progress meter callback to the function specified by FUNC. If FUNC is None, the callback will be cleared. This function will be called to provide an interactive update of the system's progress. The function will be called with three arguments, type, total, and current. If HOOK is not None, it will be supplied as fourth argument. Please see the GPGME manual for more information. """ if func is None: hookdata = None else: if hook is None: hookdata = (weakref.ref(self), func) else: hookdata = (weakref.ref(self), func, hook) gpgme.gpg_set_progress_cb(self, hookdata) def _free_progresscb(self): if gpgme.gpg_set_progress_cb: self.set_progress_cb(None) def set_status_cb(self, func, hook=None): """Sets the status callback to the function specified by FUNC. If FUNC is None, the callback will be cleared. The function will be called with two arguments, keyword and args. If HOOK is not None, it will be supplied as third argument. Please see the GPGME manual for more information. """ if func is None: hookdata = None else: if hook is None: hookdata = (weakref.ref(self), func) else: hookdata = (weakref.ref(self), func, hook) gpgme.gpg_set_status_cb(self, hookdata) def _free_statuscb(self): if gpgme.gpg_set_status_cb: self.set_status_cb(None) @property def engine_info(self): """Configuration of the engine currently in use""" p = self.protocol infos = [i for i in self.get_engine_info() if i.protocol == p] assert len(infos) == 1 return infos[0] def get_engine_info(self): """Get engine configuration Returns information about all configured and installed engines. Returns: infos -- a list of engine infos """ return gpgme.gpgme_ctx_get_engine_info(self.wrapped) def set_engine_info(self, proto, file_name=None, home_dir=None): """Change engine configuration Changes the configuration of the crypto engine implementing the protocol 'proto' for the context. Keyword arguments: file_name -- engine program file name (unchanged if None) home_dir -- configuration directory (unchanged if None) """ self.ctx_set_engine_info(proto, file_name, home_dir) def wait(self, hang): """Wait for asynchronous call to finish. Wait forever if hang is True. Raises an exception on errors. Please read the GPGME manual for more information. """ ptr = gpgme.new_gpgme_error_t_p() gpgme.gpgme_wait(self.wrapped, ptr, hang) status = gpgme.gpgme_error_t_p_value(ptr) gpgme.delete_gpgme_error_t_p(ptr) errorcheck(status) def op_edit(self, key, func, fnc_value, out): """Start key editing using supplied callback function Note: This interface is deprecated and will be removed with GPGME 1.8. Please use .interact instead. Furthermore, we implement this using gpgme_op_interact, so callbacks will get called with string keywords instead of numeric status messages. Code that is using constants.STATUS_X or constants.status.X will continue to work, whereas code using magic numbers will break as a result. """ warnings.warn( "Call to deprecated method op_edit.", category=DeprecationWarning) return self.interact(key, func, sink=out, fnc_value=fnc_value) class Data(GpgmeWrapper): """Data buffer A lot of data has to be exchanged between the user and the crypto engine, like plaintext messages, ciphertext, signatures and information about the keys. The technical details about exchanging the data information are completely abstracted by GPGME. The user provides and receives the data via `gpgme_data_t' objects, regardless of the communication protocol between GPGME and the crypto engine in use. This Data class is the implementation of the GpgmeData objects. Please see the information about __init__ for instantiation. """ _ctype = 'gpgme_data_t' _cprefix = 'gpgme_data_' def _errorcheck(self, name): """This function should list all functions returning gpgme_error_t""" # This list is compiled using # # $ grep -v '^gpgme_error_t ' obj/lang/python/python3.5-gpg/gpgme.h \ # | awk "/\(gpgme_data_t/ { printf (\"'%s',\\n\", \$2) } " \ # | sed "s/'\\*/'/" return name not in { 'gpgme_data_read', 'gpgme_data_write', 'gpgme_data_seek', 'gpgme_data_release', 'gpgme_data_release_and_get_mem', 'gpgme_data_get_encoding', 'gpgme_data_get_file_name', 'gpgme_data_set_flag', 'gpgme_data_identify', } def __init__(self, string=None, file=None, offset=None, length=None, cbs=None, copy=True): """Initialize a new gpgme_data_t object. If no args are specified, make it an empty object. If string alone is specified, initialize it with the data contained there. If file, offset, and length are all specified, file must be either a filename or a file-like object, and the object will be initialized by reading the specified chunk from the file. If cbs is specified, it MUST be a tuple of the form: (read_cb, write_cb, seek_cb, release_cb[, hook]) where the first four items are functions implementing reading, writing, seeking the data, and releasing any resources once the data object is deallocated. The functions must match the following prototypes: def read(amount, hook=None): return <a b"bytes" object> def write(data, hook=None): return <the number of bytes written> def seek(offset, whence, hook=None): return <the new file position> def release(hook=None): <return value and exceptions are ignored> The functions may be bound methods. In that case, you can simply use the 'self' reference instead of using a hook. If file is specified without any other arguments, then it must be a filename, and the object will be initialized from that file. """ super(Data, self).__init__(None) self.data_cbs = None if cbs is not None: self.new_from_cbs(*cbs) elif string is not None: self.new_from_mem(string, copy) elif file is not None and offset is not None and length is not None: self.new_from_filepart(file, offset, length) elif file is not None: if util.is_a_string(file): self.new_from_file(file, copy) else: self.new_from_fd(file) else: self.new() def __del__(self): if not gpgme: # At interpreter shutdown, gpgme is set to NONE. return if self.wrapped is not None and gpgme.gpgme_data_release: gpgme.gpgme_data_release(self.wrapped) if self._callback_excinfo: gpgme.gpg_raise_callback_exception(self) self.wrapped = None self._free_datacbs() # Implement the context manager protocol. def __enter__(self): return self def __exit__(self, type, value, tb): return False def _free_datacbs(self): self._data_cbs = None def new(self): tmp = gpgme.new_gpgme_data_t_p() errorcheck(gpgme.gpgme_data_new(tmp)) self.wrapped = gpgme.gpgme_data_t_p_value(tmp) gpgme.delete_gpgme_data_t_p(tmp) def new_from_mem(self, string, copy=True): tmp = gpgme.new_gpgme_data_t_p() errorcheck( gpgme.gpgme_data_new_from_mem(tmp, string, len(string), copy)) self.wrapped = gpgme.gpgme_data_t_p_value(tmp) gpgme.delete_gpgme_data_t_p(tmp) def new_from_file(self, filename, copy=True): tmp = gpgme.new_gpgme_data_t_p() try: errorcheck(gpgme.gpgme_data_new_from_file(tmp, filename, copy)) except errors.GPGMEError as e: if e.getcode() == errors.INV_VALUE and not copy: raise ValueError("delayed reads are not yet supported") else: raise e self.wrapped = gpgme.gpgme_data_t_p_value(tmp) gpgme.delete_gpgme_data_t_p(tmp) def new_from_cbs(self, read_cb, write_cb, seek_cb, release_cb, hook=None): tmp = gpgme.new_gpgme_data_t_p() if hook is not None: hookdata = (weakref.ref(self), read_cb, write_cb, seek_cb, release_cb, hook) else: hookdata = (weakref.ref(self), read_cb, write_cb, seek_cb, release_cb) gpgme.gpg_data_new_from_cbs(self, hookdata, tmp) self.wrapped = gpgme.gpgme_data_t_p_value(tmp) gpgme.delete_gpgme_data_t_p(tmp) def new_from_filepart(self, file, offset, length): """This wraps the GPGME gpgme_data_new_from_filepart() function. The argument "file" may be: * a string specifying a file name, or * a file-like object supporting the fileno() and the mode attribute. """ tmp = gpgme.new_gpgme_data_t_p() filename = None fp = None if util.is_a_string(file): filename = file else: fp = gpgme.fdopen(file.fileno(), file.mode) if fp is None: raise ValueError("Failed to open file from %s arg %s" % (str( type(file)), str(file))) errorcheck( gpgme.gpgme_data_new_from_filepart(tmp, filename, fp, offset, length)) self.wrapped = gpgme.gpgme_data_t_p_value(tmp) gpgme.delete_gpgme_data_t_p(tmp) def new_from_fd(self, file): """This wraps the GPGME gpgme_data_new_from_fd() function. The argument "file" must be a file-like object, supporting the fileno() method. """ tmp = gpgme.new_gpgme_data_t_p() errorcheck(gpgme.gpgme_data_new_from_fd(tmp, file.fileno())) self.wrapped = gpgme.gpgme_data_t_p_value(tmp) gpgme.delete_gpgme_data_t_p(tmp) def new_from_stream(self, file): """This wrap around gpgme_data_new_from_stream is an alias for new_from_fd() method since in python there's no difference between file stream and file descriptor.""" self.new_from_fd(file) def new_from_estream(self, file): """This wrap around gpgme_data_new_from_estream is an alias for new_from_fd() method since in python there's no difference between file stream and file descriptor, but using fd broke.""" self.new_from_stream(file) def write(self, buffer): """Write buffer given as string or bytes. If a string is given, it is implicitly encoded using UTF-8.""" written = gpgme.gpgme_data_write(self.wrapped, buffer) if written < 0: if self._callback_excinfo: gpgme.gpg_raise_callback_exception(self) else: raise GPGMEError.fromSyserror() return written def read(self, size=-1): """Read at most size bytes, returned as bytes. If the size argument is negative or omitted, read until EOF is reached. Returns the data read, or the empty string if there was no data to read before EOF was reached.""" if size == 0: return '' if size > 0: try: result = gpgme.gpgme_data_read(self.wrapped, size) except: if self._callback_excinfo: gpgme.gpg_raise_callback_exception(self) else: raise return result else: chunks = [] while True: try: result = gpgme.gpgme_data_read(self.wrapped, 4096) except: if self._callback_excinfo: gpgme.gpg_raise_callback_exception(self) else: raise if len(result) == 0: break chunks.append(result) return b''.join(chunks) def pubkey_algo_string(subkey): """Return short algorithm string Return a public key algorithm string (e.g. "rsa2048") for a given SUBKEY. Returns: algo - a string """ return gpgme.gpgme_pubkey_algo_string(subkey) def pubkey_algo_name(algo): """Return name of public key algorithm Return the name of the public key algorithm for a given numeric algorithm id ALGO (cf. RFC4880). Returns: algo - a string """ return gpgme.gpgme_pubkey_algo_name(algo) def hash_algo_name(algo): """Return name of hash algorithm Return the name of the hash algorithm for a given numeric algorithm id ALGO (cf. RFC4880). Returns: algo - a string """ return gpgme.gpgme_hash_algo_name(algo) def get_protocol_name(proto): """Get protocol description Get the string describing protocol PROTO. Returns: proto - a string """ return gpgme.gpgme_get_protocol_name(proto) def addrspec_from_uid(uid): """Return the address spec Return the addr-spec (cf. RFC2822 section 4.3) from a user id UID. Returns: addr_spec - a string """ return gpgme.gpgme_addrspec_from_uid(uid) def check_version(version=None): return gpgme.gpgme_check_version(version) # check_version also makes sure that several subsystems are properly # initialized, and it must be run at least once before invoking any # other function. We do it here so that the user does not have to do # it unless she really wants to check for a certain version. check_version() def engine_check_version(proto): try: errorcheck(gpgme.gpgme_engine_check_version(proto)) return True except errors.GPGMEError: return False def get_engine_info(): ptr = gpgme.new_gpgme_engine_info_t_p() try: errorcheck(gpgme.gpgme_get_engine_info(ptr)) info = gpgme.gpgme_engine_info_t_p_value(ptr) except errors.GPGMEError: info = None gpgme.delete_gpgme_engine_info_t_p(ptr) return info def set_engine_info(proto, file_name, home_dir=None): """Changes the default configuration of the crypto engine implementing the protocol 'proto'. 'file_name' is the file name of the executable program implementing this protocol. 'home_dir' is the directory name of the configuration directory (engine's default is used if omitted).""" errorcheck(gpgme.gpgme_set_engine_info(proto, file_name, home_dir)) def set_locale(category, value): """Sets the default locale used by contexts""" errorcheck(gpgme.gpgme_set_locale(None, category, value)) def wait(hang): """Wait for asynchronous call on any Context to finish. Wait forever if hang is True. For finished anynch calls it returns a tuple (status, context): status - status return by asnynchronous call. context - context which caused this call to return. Please read the GPGME manual of more information.""" ptr = gpgme.new_gpgme_error_t_p() context = gpgme.gpgme_wait(None, ptr, hang) status = gpgme.gpgme_error_t_p_value(ptr) gpgme.delete_gpgme_error_t_p(ptr) if context is None: errorcheck(status) else: context = Context(context) return (status, context)