# Copyright (C) 2004,2008 Igor Belyi # Copyright (C) 2002 John Goerzen # # 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 import weakref from . import pygpgme from .errors import errorcheck, GPGMEError from . import errors class GpgmeWrapper(object): """Base class all Pyme wrappers for GPGME functionality. Not to be instantiated directly.""" def __init__(self, wrapped): self._callback_excinfo = None self.wrapped = wrapped def __repr__(self): return '' % \ (__name__, self.__class__.__name__, self.wrapped) def __str__(self): return repr(self) def __hash__(self): return hash(repr(self.wrapped)) def __eq__(self, other): if other == None: return False else: return repr(self.wrapped) == repr(other.wrapped) def _getctype(self): """Must be implemented by child classes. Must return the name of the c type.""" raise NotImplementedError() def _getnameprepend(self): """Must be implemented by child classes. Must return the prefix of all c functions mapped to methods of this class.""" 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() def __getattr__(self, key): """On-the-fly function generation.""" if key[0] == '_' or self._getnameprepend() == None: return None name = self._getnameprepend() + key func = getattr(pygpgme, name) if self._errorcheck(name): def _funcwrap(slf, *args, **kwargs): result = func(slf.wrapped, *args, **kwargs) if slf._callback_excinfo: pygpgme.pygpgme_raise_callback_exception(slf) return errorcheck(result, "Invocation of " + name) else: def _funcwrap(slf, *args, **kwargs): result = func(slf.wrapped, *args, **kwargs) if slf._callback_excinfo: pygpgme.pygpgme_raise_callback_exception(slf) return result _funcwrap.__doc__ = getattr(func, "__doc__") # Monkey-patch the class. setattr(self.__class__, key, _funcwrap) # Bind the method to 'self'. def wrapper(*args, **kwargs): return _funcwrap(self, *args, **kwargs) _funcwrap.__doc__ = getattr(func, "__doc__") return wrapper class Context(GpgmeWrapper): """From the GPGME C documentation: * 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. Thus, this is the place that you will usually start.""" def _getctype(self): return 'gpgme_ctx_t' def _getnameprepend(self): return 'gpgme_' def _errorcheck(self, name): """This function should list all functions returning gpgme_error_t""" if (name.startswith('gpgme_op_') and \ not name.endswith('_result')) or \ name == 'gpgme_signers_add' or \ name == 'gpgme_set_locale' or \ name == 'gpgme_set_keylist_mode' or \ name == 'gpgme_set_protocol': return 1 return 0 def __init__(self, wrapped=None): if wrapped: self.own = False else: tmp = pygpgme.new_gpgme_ctx_t_p() errorcheck(pygpgme.gpgme_new(tmp)) wrapped = pygpgme.gpgme_ctx_t_p_value(tmp) pygpgme.delete_gpgme_ctx_t_p(tmp) self.own = True super().__init__(wrapped) self.last_passcb = None self.last_progresscb = None self.last_statuscb = None def __del__(self): if not pygpgme: # At interpreter shutdown, pygpgme is set to NONE. return self._free_passcb() self._free_progresscb() self._free_statuscb() if self.own and pygpgme.gpgme_release: pygpgme.gpgme_release(self.wrapped) def _free_passcb(self): if self.last_passcb != None: if pygpgme.pygpgme_clear_generic_cb: pygpgme.pygpgme_clear_generic_cb(self.last_passcb) if pygpgme.delete_PyObject_p_p: pygpgme.delete_PyObject_p_p(self.last_passcb) self.last_passcb = None def _free_progresscb(self): if self.last_progresscb != None: if pygpgme.pygpgme_clear_generic_cb: pygpgme.pygpgme_clear_generic_cb(self.last_progresscb) if pygpgme.delete_PyObject_p_p: pygpgme.delete_PyObject_p_p(self.last_progresscb) self.last_progresscb = None def _free_statuscb(self): if self.last_statuscb != None: if pygpgme.pygpgme_clear_generic_cb: pygpgme.pygpgme_clear_generic_cb(self.last_statuscb) if pygpgme.delete_PyObject_p_p: pygpgme.delete_PyObject_p_p(self.last_statuscb) self.last_statuscb = None 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() 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 = pygpgme.new_gpgme_key_t_p() try: errorcheck(pygpgme.gpgme_op_keylist_next(self.wrapped, ptr)) key = pygpgme.gpgme_key_t_p_value(ptr) except errors.GPGMEError as excp: key = None if excp.getcode() != errors.EOF: raise excp pygpgme.delete_gpgme_key_t_p(ptr) if key: key.__del__ = lambda self: pygpgme.gpgme_key_unref(self) return key def get_key(self, fpr, secret): """Return the key corresponding to the fingerprint 'fpr'""" ptr = pygpgme.new_gpgme_key_t_p() errorcheck(pygpgme.gpgme_get_key(self.wrapped, fpr, ptr, secret)) key = pygpgme.gpgme_key_t_p_value(ptr) pygpgme.delete_gpgme_key_t_p(ptr) if key: key.__del__ = lambda self: pygpgme.gpgme_key_unref(self) return key def op_trustlist_all(self, *args, **kwargs): self.op_trustlist_start(*args, **kwargs) trust = self.ctx.op_trustlist_next() while trust: yield trust trust = self.ctx.op_trustlist_next() 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 = pygpgme.new_gpgme_trust_item_t_p() try: errorcheck(pygpgme.gpgme_op_trustlist_next(self.wrapped, ptr)) trust = pygpgme.gpgme_trust_item_t_p_value(ptr) except errors.GPGMEError as excp: trust = None if excp.getcode() != errors.EOF: raise pygpgme.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. """ self._free_passcb() if func == None: hookdata = None else: self.last_passcb = pygpgme.new_PyObject_p_p() if hook == None: hookdata = (weakref.ref(self), func) else: hookdata = (weakref.ref(self), func, hook) pygpgme.pygpgme_set_passphrase_cb(self.wrapped, hookdata, self.last_passcb) 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. """ self._free_progresscb() if func == None: hookdata = None else: self.last_progresscb = pygpgme.new_PyObject_p_p() if hook == None: hookdata = (weakref.ref(self), func) else: hookdata = (weakref.ref(self), func, hook) pygpgme.pygpgme_set_progress_cb(self.wrapped, hookdata, self.last_progresscb) 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. """ self._free_statuscb() if func == None: hookdata = None else: self.last_statuscb = pygpgme.new_PyObject_p_p() if hook == None: hookdata = (weakref.ref(self), func) else: hookdata = (weakref.ref(self), func, hook) pygpgme.pygpgme_set_status_cb(self.wrapped, hookdata, self.last_statuscb) def get_engine_info(self): """Returns this context specific engine info""" return pygpgme.gpgme_ctx_get_engine_info(self.wrapped) def set_engine_info(self, proto, file_name, home_dir=None): """Changes the configuration of the crypto engine implementing the protocol 'proto' for the context. '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(pygpgme.gpgme_ctx_set_engine_info(self.wrapped, 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 = pygpgme.new_gpgme_error_t_p() pygpgme.gpgme_wait(self.wrapped, ptr, hang) status = pygpgme.gpgme_error_t_p_value(ptr) pygpgme.delete_gpgme_error_t_p(ptr) errorcheck(status) def op_edit(self, key, func, fnc_value, out): """Start key editing using supplied callback function""" if key == None: raise ValueError("op_edit: First argument cannot be None") if fnc_value: opaquedata = (weakref.ref(self), func, fnc_value) else: opaquedata = (weakref.ref(self), func) result = pygpgme.gpgme_op_edit(self.wrapped, key, opaquedata, out) if self._callback_excinfo: pygpgme.pygpgme_raise_callback_exception(self) errorcheck(result) class Data(GpgmeWrapper): """From the GPGME C manual: * 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.""" def _getctype(self): return 'gpgme_data_t' def _getnameprepend(self): return 'gpgme_data_' def _errorcheck(self, name): """This function should list all functions returning gpgme_error_t""" return name not in { 'gpgme_data_release_and_get_mem', 'gpgme_data_get_encoding', 'gpgme_data_seek', 'gpgme_data_get_file_name', } 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 func is a callback function taking two arguments (count, hook) and returning a string of read data, or None on EOF. This will supply the read() method for the system. If file is specified without any other arguments, then it must be a filename, and the object will be initialized from that file. Any other use will result in undefined or erroneous behavior.""" super().__init__(None) self.data_cbs = None if cbs != None: self.new_from_cbs(*cbs) elif string != None: self.new_from_mem(string, copy) elif file != None and offset != None and length != None: self.new_from_filepart(file, offset, length) elif file != None: if type(file) == type("x"): self.new_from_file(file, copy) else: self.new_from_fd(file) else: self.new() def __del__(self): if not pygpgme: # At interpreter shutdown, pygpgme is set to NONE. return if self.wrapped != None and pygpgme.gpgme_data_release: pygpgme.gpgme_data_release(self.wrapped) if self._callback_excinfo: print(self._callback_excinfo) pygpgme.pygpgme_raise_callback_exception(self) self._free_datacbs() def _free_datacbs(self): if self.data_cbs != None: if pygpgme.pygpgme_clear_generic_cb: pygpgme.pygpgme_clear_generic_cb(self.data_cbs) if pygpgme.delete_PyObject_p_p: pygpgme.delete_PyObject_p_p(self.data_cbs) self.data_cbs = None def new(self): tmp = pygpgme.new_gpgme_data_t_p() errorcheck(pygpgme.gpgme_data_new(tmp)) self.wrapped = pygpgme.gpgme_data_t_p_value(tmp) pygpgme.delete_gpgme_data_t_p(tmp) def new_from_mem(self, string, copy=True): tmp = pygpgme.new_gpgme_data_t_p() errorcheck(pygpgme.gpgme_data_new_from_mem(tmp,string,len(string),copy)) self.wrapped = pygpgme.gpgme_data_t_p_value(tmp) pygpgme.delete_gpgme_data_t_p(tmp) def new_from_file(self, filename, copy=True): tmp = pygpgme.new_gpgme_data_t_p() try: errorcheck(pygpgme.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 = pygpgme.gpgme_data_t_p_value(tmp) pygpgme.delete_gpgme_data_t_p(tmp) def new_from_cbs(self, read_cb, write_cb, seek_cb, release_cb, hook=None): assert self.data_cbs == None self.data_cbs = pygpgme.new_PyObject_p_p() tmp = pygpgme.new_gpgme_data_t_p() if hook != 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) errorcheck( pygpgme.pygpgme_data_new_from_cbs(tmp, hookdata, self.data_cbs)) self.wrapped = pygpgme.gpgme_data_t_p_value(tmp) pygpgme.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: 1. a string specifying a file name, or 3. a a file-like object. supporting the fileno() call and the mode attribute.""" tmp = pygpgme.new_gpgme_data_t_p() filename = None fp = None if type(file) == type("x"): filename = file else: fp = pygpgme.fdopen(file.fileno(), file.mode) if fp == None: raise ValueError("Failed to open file from %s arg %s" % \ (str(type(file)), str(file))) errorcheck(pygpgme.gpgme_data_new_from_filepart(tmp, filename, fp, offset, length)) self.wrapped = pygpgme.gpgme_data_t_p_value(tmp) pygpgme.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 = pygpgme.new_gpgme_data_t_p() errorcheck(pygpgme.gpgme_data_new_from_fd(tmp, file.fileno())) self.wrapped = pygpgme.gpgme_data_t_p_value(tmp) pygpgme.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 not difference between file stream and file descriptor""" self.new_from_fd(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 = pygpgme.gpgme_data_write(self.wrapped, buffer) if written < 0: if self._callback_excinfo: pygpgme.pygpgme_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 = pygpgme.gpgme_data_read(self.wrapped, size) except: if self._callback_excinfo: pygpgme.pygpgme_raise_callback_exception(self) else: raise return result else: chunks = [] while True: try: result = pygpgme.gpgme_data_read(self.wrapped, 4096) except: if self._callback_excinfo: pygpgme.pygpgme_raise_callback_exception(self) else: raise if len(result) == 0: break chunks.append(result) return b''.join(chunks) def pubkey_algo_name(algo): return pygpgme.gpgme_pubkey_algo_name(algo) def hash_algo_name(algo): return pygpgme.gpgme_hash_algo_name(algo) def get_protocol_name(proto): return pygpgme.gpgme_get_protocol_name(proto) def check_version(version=None): return pygpgme.gpgme_check_version(version) def engine_check_version (proto): try: errorcheck(pygpgme.gpgme_engine_check_version(proto)) return True except errors.GPGMEError: return False def get_engine_info(): ptr = pygpgme.new_gpgme_engine_info_t_p() try: errorcheck(pygpgme.gpgme_get_engine_info(ptr)) info = pygpgme.gpgme_engine_info_t_p_value(ptr) except errors.GPGMEError: info = None pygpgme.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(pygpgme.gpgme_set_engine_info(proto, file_name, home_dir)) def set_locale(category, value): """Sets the default locale used by contexts""" errorcheck(pygpgme.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 = pygpgme.new_gpgme_error_t_p() context = pygpgme.gpgme_wait(None, ptr, hang) status = pygpgme.gpgme_error_t_p_value(ptr) pygpgme.delete_gpgme_error_t_p(ptr) if context == None: errorcheck(status) else: context = Context(context) return (status, context)