├── src
    ├── __init__.py
    ├── img
    │   ├── icon.png
    │   └── splash.png
    ├── config.py
    ├── cross.py
    ├── wormhole.kv
    ├── main.py
    └── magic.py
├── tests
    ├── __init__.py
    └── test_magic.py
├── metadata
    └── en-US
    │   ├── title.txt
    │   ├── short_description.txt
    │   └── full_description.txt
├── misc
    ├── file_paths.xml
    ├── intent_filters.xml
    └── content_providers.xml
├── .gitignore
├── .editorconfig
├── requirements.in
├── CHANGELOG.md
├── README.md
├── requirements.txt
└── COPYING


/src/__init__.py:
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1 | 


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/tests/__init__.py:
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1 | 


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/metadata/en-US/title.txt:
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1 | Wormhole
2 | 


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/src/img/icon.png:
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https://raw.githubusercontent.com/pavelsof/mobile-wormhole/HEAD/src/img/icon.png


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/metadata/en-US/short_description.txt:
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1 | Send and receive files using the Magic Wormhole protocol
2 | 


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/src/img/splash.png:
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https://raw.githubusercontent.com/pavelsof/mobile-wormhole/HEAD/src/img/splash.png


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/misc/file_paths.xml:
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1 | <?xml version="1.0" encoding="utf-8"?>
2 | <paths xmlns:android="http://schemas.android.com/apk/res/android">
3 | 	<external-path name="external_files" path="." />
4 | </paths>
5 | 


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/misc/intent_filters.xml:
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1 | <intent-filter>
2 | 	<action android:name="android.intent.action.SEND" />
3 | 	<category android:name="android.intent.category.DEFAULT" />
4 | 	<data android:mimeType="*/*" />
5 | </intent-filter>
6 | 


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/.gitignore:
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 1 | # virtual env
 2 | /venv/*
 3 | 
 4 | # buildozer build dir
 5 | /.buildozer/*
 6 | 
 7 | # buildozer output dir
 8 | /bin/*
 9 | 
10 | # config file
11 | /src/wormhole.ini
12 | 
13 | # python temps
14 | *.pyc
15 | 
16 | # editor temps
17 | *.swp
18 | 


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/.editorconfig:
--------------------------------------------------------------------------------
 1 | root = true
 2 | 
 3 | [*]
 4 | charset = utf-8
 5 | end_of_line = lf
 6 | insert_final_newline = true
 7 | trim_trailing_whitespace = true
 8 | 
 9 | [*.py]
10 | indent_style = space
11 | indent_size = 4
12 | max_line_length = 79
13 | 
14 | [*.kv]
15 | indent_style = space
16 | indent_size = 4
17 | 


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/misc/content_providers.xml:
--------------------------------------------------------------------------------
 1 | <provider
 2 | 	android:name="android.support.v4.content.FileProvider"
 3 | 	android:authorities="com.pavelsof.wormhole.fileprovider"
 4 | 	android:exported="false"
 5 | 	android:grantUriPermissions="true">
 6 | 	<meta-data
 7 | 		android:name="android.support.FILE_PROVIDER_PATHS"
 8 | 		android:resource="@xml/file_paths" />
 9 | </provider>
10 | 


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/requirements.in:
--------------------------------------------------------------------------------
 1 | # what goes in the app
 2 | kivy[base]==2.1.0
 3 | magic-wormhole==0.12.0
 4 | plyer==2.0.0
 5 | 
 6 | # what builds the app
 7 | git+https://github.com/pavelsof/buildozer@c4b4fdf0c803418a23efee9852702e67414617c5
 8 | cython==0.29.32
 9 | 
10 | # unit tests
11 | pytest==7.1.3
12 | pytest-twisted==1.13.4
13 | 
14 | # other tools
15 | ipython==8.5.0
16 | pip-tools==6.8.0
17 | pipdeptree==2.3.1
18 | pyflakes==2.5.0
19 | 


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/CHANGELOG.md:
--------------------------------------------------------------------------------
 1 | # changelog
 2 | 
 3 | ## 0.2.1 (2021-01-23)
 4 | 
 5 | - The app keeps the screen on while in foreground ([#8](https://github.com/pavelsof/mobile-wormhole/issues/8)).
 6 | 
 7 | 
 8 | ## 0.2.0 (2020-12-12)
 9 | 
10 | - Upgraded to Kivy 2.0.
11 | - Added a config screen for setting the rendezvous and transit relay servers ([#4](https://github.com/pavelsof/mobile-wormhole/issues/4)).
12 | - The send/receive screens now show the file upload/download progress ([#5](https://github.com/pavelsof/mobile-wormhole/issues/5)).
13 | 


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/metadata/en-US/full_description.txt:
--------------------------------------------------------------------------------
 1 | This is an Android client for the <a href="https://github.com/warner/magic-wormhole">Magic Wormhole</a> protocol. You can use it to exchange files between your phone and another Magic Wormhole client, including the original command-line client.
 2 | 
 3 | How to send files
 4 | 
 5 | * From the main screen, tap the "send" button. Then use the "choose file" button to pick the file that you want to send.
 6 | * Alternatively, open the file that you want to send and tap the share icon: Wormhole should be listed among the apps you can use to share the file.
 7 | * Either way, the app will have generated a code, a random number followed by two random words. The person to whom you want to send the file will have to enter this code in their Magic Wormhole client. The code is also copied to the clipboard for convenience.
 8 | * Tap the "send" button. When the user at the other end of the wormhole enters the code and confirms, the file will start transferring.
 9 | * The "send" button will change to "done" when the transfer is complete.
10 | 
11 | How to receive files
12 | 
13 | * From the main screen, tap the "receive" button.
14 | * Enter the code that the sender has provided you with and tap the "connect" button.
15 | * You will see the incoming file's name and size. If all looks good, tap the "receive" button to start the file transfer.
16 | * When the file is downloaded from the wormhole, the "receive" button will change to an "open dir" button.
17 | 
18 | The app is still in beta and there is still a lot to be desired. However, the basic functionality of sending and receiving files seems to be there. I find it useful, so someone else might as well.
19 | 
20 | The code is <a href="https://github.com/pavelsof/mobile-wormhole">open sourced</a> under GPLv3. Pull requests are welcome.
21 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | # Wormhole
 2 | 
 3 | This is a work-in-progress mobile client for the [magic wormhole][magic-wormhole] protocol. What already works:
 4 | 
 5 | - Sending files. The app can obtain a code, exchange keys with the other party, allow the user to pick a file to send down the wormhole, and then actually transfer the file.
 6 | - Receiving files. The user can enter a code, view a file offer to confirm or reject, and indeed receive a file. This will be saved in the downloads directory.
 7 | - Handling of Android's `ACTION_SEND` intent. The user can share a file via the app, essentially pre-selecting the file in the send screen.
 8 | 
 9 | [<img src="https://fdroid.gitlab.io/artwork/badge/get-it-on.png"
10 |      alt="Get it on F-Droid"
11 |      height="80">](https://f-droid.org/packages/com.pavelsof.wormhole/)
12 | [<img src="https://play.google.com/intl/en_us/badges/images/generic/en-play-badge.png"
13 |      alt="Get it on Google Play"
14 |      height="80">](https://play.google.com/store/apps/details?id=com.pavelsof.wormhole)
15 | 
16 | ## Setup
17 | 
18 | In order to leverage the original [magic wormhole][magic-wormhole] package and also because I was curious whether it will even work, the code is written in Python using [Kivy][kivy] and friends.
19 | 
20 | ```sh
21 | # create a virtual environment
22 | # version 3.8 should work
23 | python3 -m venv venv
24 | source venv/bin/activate
25 | 
26 | # install the dependencies
27 | # pip-sync is also fine
28 | pip install --upgrade pip
29 | pip install -r requirements.txt
30 | 
31 | # run the (too) few unit tests
32 | pytest tests
33 | 
34 | # run locally
35 | python src/main.py
36 | 
37 | # run on an android phone
38 | buildozer android debug deploy run logcat
39 | ```
40 | 
41 | If you also feel adventurous about mobile apps in Python.. pull requests are welcome :)
42 | 
43 | 
44 | ## Licence
45 | 
46 | GPL. You can do what you want with this code as long as you let others do the same.
47 | 
48 | [magic-wormhole]: https://github.com/warner/magic-wormhole
49 | [kivy]: https://github.com/kivy/kivy
50 | 


--------------------------------------------------------------------------------
/src/config.py:
--------------------------------------------------------------------------------
 1 | from kivy.app import App
 2 | from kivy.uix.screenmanager import Screen
 3 | from wormhole.cli.public_relay import RENDEZVOUS_RELAY, TRANSIT_RELAY
 4 | 
 5 | 
 6 | SECTION_NAME = 'wormhole'
 7 | 
 8 | DEFAULT_VALUES = {
 9 |     'rendezvous_relay': RENDEZVOUS_RELAY,
10 |     'transit_relay': TRANSIT_RELAY,
11 | }
12 | 
13 | FIELD_NAMES = frozenset(DEFAULT_VALUES.keys())
14 | 
15 | 
16 | class ConfigScreen(Screen):
17 | 
18 |     def on_pre_enter(self):
19 |         """
20 |         Set the values of the text inputs. Assume that self.config has been
21 |         already set by the ConfigMixin.build_settings method.
22 | 
23 |         Called just before the user enters this screen.
24 |         """
25 |         assert self.config
26 | 
27 |         for field_name in FIELD_NAMES:
28 |             field = getattr(self.ids, field_name)
29 |             field.text = self.config.get(SECTION_NAME, field_name)
30 | 
31 |     def reset_field(self, field_name):
32 |         """
33 |         Reset the value of the given field to its default.
34 |         """
35 |         field = getattr(self.ids, field_name)
36 |         field.text = DEFAULT_VALUES[field_name]
37 | 
38 |     def update_config(self):
39 |         """
40 |         Update the config with the values that happen to be in the input fields
41 |         when the user calls this action.
42 |         """
43 |         for field_name in FIELD_NAMES:
44 |             value = getattr(self.ids, field_name).text
45 |             self.config.set(SECTION_NAME, field_name, value)
46 | 
47 |         self.config.write()
48 | 
49 | 
50 | class ConfigMixin:
51 |     """
52 |     Mixin for our App subclass that determines the config options and the way
53 |     to display these to the user.
54 |     """
55 |     settings_cls = ConfigScreen
56 |     use_kivy_settings = False
57 | 
58 |     def build_config(self, config):
59 |         """
60 |         Mutate self.config before the config file (if this exists) is loaded in
61 |         order to provide default config values.
62 | 
63 |         Called once, before the application is initialised.
64 |         """
65 |         config.setdefaults(SECTION_NAME, DEFAULT_VALUES)
66 | 
67 |     def build_settings(self, settings):
68 |         """
69 |         Mutate the settings widget before this is shown to the user in order to
70 |         link in the config.
71 | 
72 |         Called once, when the settings widget is created.
73 |         """
74 |         settings.config = self.config
75 | 
76 |     def display_settings(self, settings):
77 |         """
78 |         Determine the way to show the settings widget to the user. In our case,
79 |         attach the config screen (if it is not already) and switch to it.
80 | 
81 |         Called by the app.open_settings method.
82 |         """
83 |         if not self.screen_manager.has_screen('config_screen'):
84 |             self.screen_manager.add_widget(settings)
85 | 
86 |         self.screen_manager.current = 'config_screen'
87 | 
88 | 
89 | def get_config():
90 |     """
91 |     Return a dict mapping all config keys to their stored values.
92 |     """
93 |     app = App.get_running_app()
94 |     return {
95 |         field_name: app.config.get(SECTION_NAME, field_name)
96 |         for field_name in FIELD_NAMES
97 |     }
98 | 


--------------------------------------------------------------------------------
/requirements.txt:
--------------------------------------------------------------------------------
  1 | #
  2 | # This file is autogenerated by pip-compile with python 3.10
  3 | # To update, run:
  4 | #
  5 | #    pip-compile
  6 | #
  7 | asttokens==2.0.8
  8 |     # via stack-data
  9 | attrs==22.1.0
 10 |     # via
 11 |     #   autobahn
 12 |     #   automat
 13 |     #   magic-wormhole
 14 |     #   pytest
 15 |     #   service-identity
 16 |     #   twisted
 17 | autobahn[twisted]==22.7.1
 18 |     # via magic-wormhole
 19 | automat==20.2.0
 20 |     # via
 21 |     #   magic-wormhole
 22 |     #   twisted
 23 |     #   txtorcon
 24 | backcall==0.2.0
 25 |     # via ipython
 26 | build==0.8.0
 27 |     # via pip-tools
 28 | buildozer @ git+https://github.com/pavelsof/buildozer@c4b4fdf0c803418a23efee9852702e67414617c5
 29 |     # via -r requirements.in
 30 | certifi==2022.6.15.2
 31 |     # via requests
 32 | cffi==1.15.1
 33 |     # via
 34 |     #   cryptography
 35 |     #   pynacl
 36 | charset-normalizer==2.1.1
 37 |     # via requests
 38 | click==8.1.3
 39 |     # via
 40 |     #   magic-wormhole
 41 |     #   pip-tools
 42 | constantly==15.1.0
 43 |     # via twisted
 44 | cryptography==38.0.1
 45 |     # via
 46 |     #   autobahn
 47 |     #   pyopenssl
 48 |     #   service-identity
 49 |     #   txtorcon
 50 | cython==0.29.32
 51 |     # via -r requirements.in
 52 | decorator==5.1.1
 53 |     # via
 54 |     #   ipython
 55 |     #   pytest-twisted
 56 | distlib==0.3.6
 57 |     # via virtualenv
 58 | docutils==0.19
 59 |     # via kivy
 60 | executing==1.0.0
 61 |     # via stack-data
 62 | filelock==3.8.0
 63 |     # via virtualenv
 64 | greenlet==1.1.3
 65 |     # via pytest-twisted
 66 | hkdf==0.0.3
 67 |     # via
 68 |     #   magic-wormhole
 69 |     #   spake2
 70 | humanize==4.3.0
 71 |     # via magic-wormhole
 72 | hyperlink==21.0.0
 73 |     # via
 74 |     #   autobahn
 75 |     #   twisted
 76 | idna==3.3
 77 |     # via
 78 |     #   hyperlink
 79 |     #   requests
 80 |     #   twisted
 81 | incremental==21.3.0
 82 |     # via
 83 |     #   twisted
 84 |     #   txtorcon
 85 | iniconfig==1.1.1
 86 |     # via pytest
 87 | ipython==8.5.0
 88 |     # via -r requirements.in
 89 | jedi==0.18.1
 90 |     # via ipython
 91 | kivy[base]==2.1.0
 92 |     # via -r requirements.in
 93 | kivy-garden==0.1.5
 94 |     # via kivy
 95 | magic-wormhole==0.12.0
 96 |     # via -r requirements.in
 97 | matplotlib-inline==0.1.6
 98 |     # via ipython
 99 | packaging==21.3
100 |     # via
101 |     #   build
102 |     #   pytest
103 | parso==0.8.3
104 |     # via jedi
105 | pep517==0.13.0
106 |     # via build
107 | pexpect==4.8.0
108 |     # via
109 |     #   buildozer
110 |     #   ipython
111 | pickleshare==0.7.5
112 |     # via ipython
113 | pillow==9.2.0
114 |     # via kivy
115 | pip-tools==6.8.0
116 |     # via -r requirements.in
117 | pipdeptree==2.3.1
118 |     # via -r requirements.in
119 | platformdirs==2.5.2
120 |     # via virtualenv
121 | pluggy==1.0.0
122 |     # via pytest
123 | plyer==2.0.0
124 |     # via -r requirements.in
125 | prompt-toolkit==3.0.31
126 |     # via ipython
127 | ptyprocess==0.7.0
128 |     # via pexpect
129 | pure-eval==0.2.2
130 |     # via stack-data
131 | py==1.11.0
132 |     # via pytest
133 | pyasn1==0.4.8
134 |     # via
135 |     #   pyasn1-modules
136 |     #   service-identity
137 | pyasn1-modules==0.2.8
138 |     # via service-identity
139 | pycparser==2.21
140 |     # via cffi
141 | pyflakes==2.5.0
142 |     # via -r requirements.in
143 | pygments==2.13.0
144 |     # via
145 |     #   ipython
146 |     #   kivy
147 | pynacl==1.5.0
148 |     # via magic-wormhole
149 | pyopenssl==22.0.0
150 |     # via twisted
151 | pyparsing==3.0.9
152 |     # via packaging
153 | pytest==7.1.3
154 |     # via
155 |     #   -r requirements.in
156 |     #   pytest-twisted
157 | pytest-twisted==1.13.4
158 |     # via -r requirements.in
159 | requests==2.28.1
160 |     # via kivy-garden
161 | service-identity==21.1.0
162 |     # via twisted
163 | sh==1.14.3
164 |     # via buildozer
165 | six==1.16.0
166 |     # via
167 |     #   asttokens
168 |     #   automat
169 |     #   magic-wormhole
170 |     #   service-identity
171 | spake2==0.8
172 |     # via magic-wormhole
173 | stack-data==0.5.0
174 |     # via ipython
175 | tomli==2.0.1
176 |     # via
177 |     #   build
178 |     #   pep517
179 |     #   pytest
180 | tqdm==4.64.1
181 |     # via magic-wormhole
182 | traitlets==5.4.0
183 |     # via
184 |     #   ipython
185 |     #   matplotlib-inline
186 | twisted[tls]==22.8.0
187 |     # via
188 |     #   autobahn
189 |     #   magic-wormhole
190 |     #   txtorcon
191 | txaio==22.2.1
192 |     # via autobahn
193 | txtorcon==22.0.0
194 |     # via magic-wormhole
195 | typing-extensions==4.3.0
196 |     # via twisted
197 | urllib3==1.26.12
198 |     # via requests
199 | virtualenv==20.16.5
200 |     # via buildozer
201 | wcwidth==0.2.5
202 |     # via prompt-toolkit
203 | wheel==0.37.1
204 |     # via pip-tools
205 | zope-interface==5.4.0
206 |     # via
207 |     #   autobahn
208 |     #   twisted
209 |     #   txtorcon
210 | 
211 | # The following packages are considered to be unsafe in a requirements file:
212 | # pip
213 | # setuptools
214 | 


--------------------------------------------------------------------------------
/tests/test_magic.py:
--------------------------------------------------------------------------------
  1 | import os.path
  2 | from unittest.mock import Mock
  3 | 
  4 | import pytest
  5 | import pytest_twisted
  6 | from twisted.internet import reactor
  7 | from twisted.internet.defer import Deferred, fail, succeed
  8 | from wormhole.errors import WrongPasswordError
  9 | from wormhole.util import dict_to_bytes
 10 | 
 11 | from src.magic import HumanError, SuspiciousOperation, Timeout, Wormhole
 12 | 
 13 | 
 14 | @pytest.fixture
 15 | def upstream(monkeypatch):
 16 |     upstream = Mock()
 17 | 
 18 |     def mock_init(self):
 19 |         self.app_id = ''
 20 |         self.transit_relay = ''
 21 |         self.transit = None
 22 |         self.wormhole = upstream
 23 | 
 24 |     monkeypatch.setattr(Wormhole, '__init__', mock_init)
 25 | 
 26 |     return upstream
 27 | 
 28 | 
 29 | @pytest.fixture
 30 | def file_path(tmpdir):
 31 |     file_path = os.path.join(tmpdir, 'file')
 32 | 
 33 |     with open(file_path, 'w') as f:
 34 |         f.write('hi!')
 35 | 
 36 |     return file_path
 37 | 
 38 | 
 39 | @pytest_twisted.inlineCallbacks
 40 | def test_generate_code_timeout(upstream):
 41 |     """
 42 |     The Wormhole.generate_code method should be able to handle timeouts.
 43 |     """
 44 |     def get_code():
 45 |         deferred = Deferred()
 46 |         reactor.callLater(2, deferred.callback, 'code')
 47 |         return deferred
 48 |     upstream.get_code = get_code
 49 | 
 50 |     wormhole = Wormhole()
 51 |     with pytest.raises(Timeout):
 52 |         yield wormhole.generate_code(timeout=0)
 53 | 
 54 | 
 55 | @pytest_twisted.inlineCallbacks
 56 | def test_generate_code_works(upstream):
 57 |     """
 58 |     The Wormhole.generate_code method should resolve into a code generated by
 59 |     the upstream if all goes well.
 60 |     """
 61 |     upstream.get_code = lambda: succeed('code')
 62 | 
 63 |     wormhole = Wormhole()
 64 |     res = yield wormhole.generate_code()
 65 |     assert res == 'code'
 66 | 
 67 | 
 68 | @pytest_twisted.inlineCallbacks
 69 | def test_connect_works(upstream):
 70 |     """
 71 |     The Wormhole.connect method should resolve if the upstream resolves.
 72 |     """
 73 |     upstream.get_code = lambda: succeed(None)
 74 |     wormhole = Wormhole()
 75 |     res = yield wormhole.connect('code')
 76 |     assert res is None
 77 | 
 78 | 
 79 | @pytest_twisted.inlineCallbacks
 80 | def test_exchange_keys_bad_code(upstream):
 81 |     """
 82 |     The Wormhole.exchange_keys method should be able to handle the upstream's
 83 |     WrongPasswordError.
 84 |     """
 85 |     upstream.get_verifier = lambda: fail(WrongPasswordError())
 86 | 
 87 |     wormhole = Wormhole()
 88 |     with pytest.raises(HumanError):
 89 |         yield wormhole.exchange_keys()
 90 | 
 91 | 
 92 | @pytest_twisted.inlineCallbacks
 93 | def test_exchange_keys_works(upstream):
 94 |     """
 95 |     The Wormhole.exchange_keys method should resolve into a verifier coming
 96 |     from the upstream if all goes well.
 97 |     """
 98 |     upstream.get_verifier = lambda: succeed('verifier')
 99 | 
100 |     wormhole = Wormhole()
101 |     res = yield wormhole.exchange_keys()
102 |     assert res == 'verifier'
103 | 
104 | 
105 | @pytest_twisted.inlineCallbacks
106 | def test_await_json_timeout(upstream):
107 |     """
108 |     The Wormhole.await_json method should be able to handle timeouts.
109 |     """
110 |     def get_message():
111 |         deferred = Deferred()
112 |         reactor.callLater(2, deferred.callback, dict_to_bytes({}))
113 |         return deferred
114 |     upstream.get_message = get_message
115 | 
116 |     wormhole = Wormhole()
117 |     with pytest.raises(Timeout):
118 |         yield wormhole.await_json(timeout=0)
119 | 
120 | 
121 | @pytest_twisted.inlineCallbacks
122 | def test_await_json_bad_message(upstream):
123 |     """
124 |     The Wormhole.await_json method should not break if the upstream resolves
125 |     into a message that does not conform to the wormhole spec.
126 |     """
127 |     upstream.get_message = lambda: succeed('some string')
128 | 
129 |     wormhole = Wormhole()
130 |     with pytest.raises(SuspiciousOperation):
131 |         yield wormhole.await_json()
132 | 
133 | 
134 | @pytest_twisted.inlineCallbacks
135 | def test_await_json_works(upstream):
136 |     """
137 |     The Wormhole.await_json method should resolve into a dict parsed from the
138 |     upstream's return value.
139 |     """
140 |     upstream.get_message = lambda: succeed(dict_to_bytes({'answer': 42}))
141 | 
142 |     wormhole = Wormhole()
143 |     res = yield wormhole.await_json()
144 |     assert res == {'answer': 42}
145 | 
146 | 
147 | @pytest_twisted.inlineCallbacks
148 | def test_send_file_error(upstream, file_path):
149 |     """
150 |     The Wormhole.send_file method should close the wormhole and reject with an
151 |     appropriate error if the other side sends an error message.
152 |     """
153 |     upstream.get_message = lambda: succeed(dict_to_bytes({'error': '!'}))
154 | 
155 |     wormhole = Wormhole()
156 | 
157 |     with pytest.raises(SuspiciousOperation) as exc_info:
158 |         yield wormhole.send_file(file_path, lambda _: None)
159 | 
160 |     assert str(exc_info.value) == '!'
161 |     assert upstream.close.called
162 | 
163 | 
164 | @pytest_twisted.inlineCallbacks
165 | def test_await_offer_error(upstream):
166 |     """
167 |     The Wormhole.await_offer method should close the wormhole and reject with
168 |     an appropriate error if the other side sends an error message.
169 |     """
170 |     upstream.get_message = lambda: succeed(dict_to_bytes({'error': '!'}))
171 |     upstream.derive_key = lambda *args: bytes('key', 'utf-8')
172 | 
173 |     wormhole = Wormhole()
174 | 
175 |     with pytest.raises(SuspiciousOperation) as exc_info:
176 |         yield wormhole.await_offer()
177 | 
178 |     assert str(exc_info.value) == '!'
179 |     assert upstream.close.called
180 | 


--------------------------------------------------------------------------------
/src/cross.py:
--------------------------------------------------------------------------------
  1 | import mimetypes
  2 | import os
  3 | 
  4 | from kivy.utils import platform as PLATFORM
  5 | 
  6 | 
  7 | if PLATFORM == 'android':
  8 |     import android.activity
  9 |     from android import mActivity
 10 |     from android.permissions import Permission
 11 |     from android.permissions import check_permission, request_permissions
 12 |     from android.storage import primary_external_storage_path
 13 |     from jnius import autoclass
 14 |     from plyer.platforms.android.filechooser import AndroidFileChooser
 15 | 
 16 |     File = autoclass('java.io.File')
 17 | 
 18 |     Intent = autoclass('android.content.Intent')
 19 |     Environment = autoclass('android.os.Environment')
 20 |     FileProvider = autoclass('android.support.v4.content.FileProvider')
 21 | 
 22 |     class AndroidUriResolver(AndroidFileChooser):
 23 |         """
 24 |         Leverage Plyer's file chooser for resolving Android URIs.
 25 |         """
 26 | 
 27 |         def __init__(self):
 28 |             pass
 29 | 
 30 |         def resolve(self, uri):
 31 |             return self._resolve_uri(uri)
 32 | 
 33 | 
 34 | """
 35 | permissions
 36 | """
 37 | 
 38 | 
 39 | def ensure_storage_perms(fallback_func):
 40 |     """
 41 |     Decorator that ensures that the decorated function is only run if the user
 42 |     has granted the app permissions to write to the file system. Otherwise the
 43 |     fallback function is called instead.
 44 | 
 45 |     Because permissions on Android are requested asynchronously, the decorated
 46 |     function should not be expected to return a value.
 47 |     """
 48 |     def outer_wrapper(func):
 49 |         def inner_wrapper(*args, **kwargs):
 50 |             if PLATFORM == 'android':
 51 |                 if check_permission(Permission.WRITE_EXTERNAL_STORAGE):
 52 |                     return func(*args, **kwargs)
 53 | 
 54 |                 def callback(permissions, grant_results):
 55 |                     if grant_results[0]:
 56 |                         return func(*args, **kwargs)
 57 |                     else:
 58 |                         return fallback_func()
 59 | 
 60 |                 request_permissions(
 61 |                     [Permission.WRITE_EXTERNAL_STORAGE], callback
 62 |                 )
 63 |                 return
 64 | 
 65 |             return func(*args, **kwargs)
 66 | 
 67 |         return inner_wrapper
 68 |     return outer_wrapper
 69 | 
 70 | 
 71 | """
 72 | directories
 73 | """
 74 | 
 75 | 
 76 | def get_downloads_dir():
 77 |     """
 78 |     Return the path to the user's downloads dir.
 79 |     """
 80 |     if PLATFORM == 'android':
 81 |         return os.path.join(
 82 |             primary_external_storage_path(),
 83 |             Environment.DIRECTORY_DOWNLOADS
 84 |         )
 85 |     else:
 86 |         return os.getcwd()
 87 | 
 88 | 
 89 | def open_file(path):
 90 |     """
 91 |     Open the specified file.
 92 | 
 93 |     On Android, for the ACTION_VIEW to work, the Uri supplied to the Intent has
 94 |     to be sanctioned by the FileProvider (i.e. Uri.fromFile does not work), so:
 95 | 
 96 |     - The legacy android.support.v4.content.FileProvider has to be added to the
 97 |       app because AndroidX is not yet supported by Kivy [1]. In practice, this
 98 |       means adding a gradle dependency in buildozer.spec.
 99 |     - The FileProvider requires a bit of boilerplate XML in the AndroidManifest
100 |       and one other file [2].
101 | 
102 |     As the second does not seem to be currently configurable via Buildozer, the
103 |     latter is set to use a dedicated fork and branch of python-for-android [3].
104 | 
105 |     [1]: https://github.com/kivy/python-for-android/issues/2020
106 |     [2]: https://developer.android.com/reference/android/support/v4/content/FileProvider
107 |     [3]: https://github.com/pavelsof/python-for-android/tree/with-fileprovider
108 |     """
109 |     mime_type, _ = mimetypes.guess_type(path)
110 | 
111 |     if PLATFORM == 'android':
112 |         uri = FileProvider.getUriForFile(
113 |             mActivity, 'com.pavelsof.wormhole.fileprovider', File(path)
114 |         )
115 | 
116 |         intent = Intent()
117 |         intent.setAction(Intent.ACTION_VIEW)
118 |         intent.setDataAndType(uri, mime_type)
119 |         intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
120 |         intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
121 | 
122 |         mActivity.startActivity(intent)
123 | 
124 | 
125 | """
126 | handling intents
127 | """
128 | 
129 | 
130 | class IntentHandler:
131 | 
132 |     def __init__(self):
133 |         """
134 |         On Android, set the handler listening for incoming ACTION_SEND intents,
135 |         including the intent that has launched the current activity.
136 | 
137 |         On other platforms, do nothing.
138 |         """
139 |         self.data = None
140 |         self.error = None
141 | 
142 |         if PLATFORM == 'android':
143 |             self.uri_resolver = AndroidUriResolver()
144 |             self.handle_android_intent(mActivity.getIntent())
145 |             android.activity.bind(on_new_intent=self.handle_android_intent)
146 | 
147 |     def handle_android_intent(self, intent):
148 |         """
149 |         Handle incoming ACTION_SEND intents on Android.
150 |         """
151 |         if intent.getAction() != 'android.intent.action.SEND':
152 |             return
153 | 
154 |         self.data = None
155 |         self.error = None
156 | 
157 |         try:
158 |             if intent.getData():
159 |                 uri = intent.getData()
160 | 
161 |             else:
162 |                 clipData = intent.getClipData()
163 | 
164 |                 assert clipData is not None
165 |                 assert clipData.getItemCount()
166 | 
167 |                 uri = clipData.getItemAt(0).getUri()
168 | 
169 |             self.data = self.uri_resolver.resolve(uri)
170 |         except (AttributeError, AssertionError):
171 |             self.error = (
172 |                 'Your share target cannot be recognised as a file. '
173 |                 'If it is indeed one, '
174 |                 'please try selecting it via the file chooser instead.'
175 |             )
176 | 
177 |     def pop(self):
178 |         """
179 |         If there is a file path in our improvised single-slot buffer, pop it.
180 |         If there is an error instead, raise it. Otherwise return None.
181 |         """
182 |         if self.error:
183 |             error = str(self.error)
184 |             self.error = None
185 |             raise ValueError(error)
186 |         else:
187 |             data = self.data
188 |             self.data = None
189 |             return data
190 | 
191 | 
192 | intent_hander = IntentHandler()
193 | 


--------------------------------------------------------------------------------
/src/wormhole.kv:
--------------------------------------------------------------------------------
  1 | #:kivy 1.11.1
  2 | 
  3 | <Button>:
  4 |     font_size: 30
  5 |     halign: 'center'
  6 |     padding_y: 30
  7 |     size_hint: None, None
  8 |     strip: True
  9 |     width: 250
 10 | 
 11 | 
 12 | <Label>:
 13 |     font_size: 30
 14 |     halign: 'center'
 15 |     height: self.texture_size[1]
 16 |     line_height: 1
 17 |     size_hint_y: None
 18 |     strip: True
 19 |     text_size: self.width - 16, None
 20 |     valign: 'middle'
 21 | 
 22 | 
 23 | <TextInput>:
 24 |     font_size: 30
 25 |     height: self.minimum_height
 26 |     padding: 20, 20
 27 | 
 28 | 
 29 | <ErrorPopup>:
 30 |     size_hint: 0.8, 0.5
 31 |     title: root.title
 32 |     title_size: 30
 33 | 
 34 |     BoxLayout:
 35 |         orientation: 'vertical'
 36 | 
 37 |         AnchorLayout:
 38 |             Label:
 39 |                 halign: 'left'
 40 |                 text: root.message
 41 | 
 42 |         AnchorLayout:
 43 |             Button:
 44 |                 text: 'ok'
 45 |                 on_release: root.dismiss()
 46 | 
 47 | 
 48 | <HomeScreen>:
 49 |     name: 'home_screen'
 50 | 
 51 |     BoxLayout:
 52 |         orientation: 'vertical'
 53 | 
 54 |         AnchorLayout:
 55 |             Label:
 56 |                 font_size: 50
 57 |                 halign: 'center'
 58 |                 text: 'Wormhole'
 59 | 
 60 |         AnchorLayout:
 61 |             Button:
 62 |                 text: 'send'
 63 |                 on_release: root.manager.current = 'send_screen'
 64 | 
 65 |         AnchorLayout:
 66 |             Button:
 67 |                 text: 'receive'
 68 |                 on_release: root.manager.current = 'receive_screen'
 69 | 
 70 |         AnchorLayout:
 71 |             Button:
 72 |                 text: 'config'
 73 |                 on_release: app.open_settings()
 74 | 
 75 | 
 76 | <SendScreen>:
 77 |     name: 'send_screen'
 78 | 
 79 |     BoxLayout:
 80 |         orientation: 'vertical'
 81 | 
 82 |         AnchorLayout:
 83 |             BoxLayout:
 84 |                 orientation: 'vertical'
 85 |                 size_hint_y: None
 86 | 
 87 |                 Label:
 88 |                     text: 'your code is' if root.has_code else 'generating code'
 89 | 
 90 |                 Label:
 91 |                     font_size: 50
 92 |                     padding_y: 10
 93 |                     text: root.code
 94 | 
 95 |                 Label:
 96 |                     font_size: 20
 97 |                     text: '(copied in your clipboard)' if root.has_code else ''
 98 | 
 99 |         BoxLayout:
100 |             orientation: 'vertical'
101 | 
102 |             AnchorLayout:
103 |                 Button:
104 |                     text: 'choose file'
105 |                     on_release: root.open_file_chooser()
106 | 
107 |             AnchorLayout:
108 |                 BoxLayout:
109 |                     orientation: 'vertical'
110 |                     padding_x: 50
111 |                     size_hint_y: None
112 | 
113 |                     Label:
114 |                         text: 'file name: {}'.format(root.file_name)
115 | 
116 |                     Label:
117 |                         text: 'file size: {}'.format(root.file_size)
118 | 
119 |                     Label:
120 |                         text: 'transferred: {}'.format(root.transferred)
121 | 
122 |         BoxLayout:
123 |             orientation: 'horizontal'
124 | 
125 |             AnchorLayout:
126 |                 Button:
127 |                     text: 'cancel'
128 |                     on_release: root.manager.current = 'home_screen'
129 | 
130 |             AnchorLayout:
131 |                 Button:
132 |                     disabled: root.send_button_disabled
133 |                     text: root.send_button_text
134 |                     on_release: root.send()
135 | 
136 | 
137 | <ReceiveScreen>:
138 |     name: 'receive_screen'
139 | 
140 |     BoxLayout:
141 |         orientation: 'vertical'
142 | 
143 |         BoxLayout:
144 |             orientation: 'vertical'
145 | 
146 |             AnchorLayout:
147 |                 TextInput:
148 |                     id: code_input
149 |                     multiline: False
150 |                     size_hint: 0.8, None
151 | 
152 |             AnchorLayout:
153 |                 Button:
154 |                     disabled: root.connect_button_disabled
155 |                     text: root.connect_button_text
156 |                     on_release: root.open_wormhole()
157 | 
158 |         AnchorLayout:
159 |             BoxLayout:
160 |                 orientation: 'vertical'
161 |                 size_hint_y: None
162 | 
163 |                 Label:
164 |                     text: 'file name: {}'.format(root.file_name)
165 | 
166 |                 Label:
167 |                     text: 'file size: {}'.format(root.file_size)
168 | 
169 |                 Label:
170 |                     text: 'transferred: {}'.format(root.transferred)
171 | 
172 |         BoxLayout:
173 |             orientation: 'horizontal'
174 | 
175 |             AnchorLayout:
176 |                 Button:
177 |                     text: 'cancel'
178 |                     on_release: root.manager.current = 'home_screen'
179 | 
180 |             AnchorLayout:
181 |                 Button:
182 |                     disabled: root.accept_button_disabled
183 |                     text: root.accept_button_text
184 |                     on_release: root.accept_button_func()
185 | 
186 | 
187 | <ConfigScreen>:
188 |     name: 'config_screen'
189 | 
190 |     BoxLayout:
191 |         orientation: 'vertical'
192 | 
193 |         BoxLayout:
194 |             orientation: 'vertical'
195 | 
196 |             AnchorLayout:
197 |                 Label:
198 |                     text: 'rendezvous relay'
199 | 
200 |             AnchorLayout:
201 |                 TextInput:
202 |                     id: rendezvous_relay
203 |                     multiline: False
204 |                     size_hint: 0.8, None
205 | 
206 |             AnchorLayout:
207 |                 Button:
208 |                     text: 'reset'
209 |                     on_release: root.reset_field('rendezvous_relay')
210 | 
211 |         BoxLayout:
212 |             orientation: 'vertical'
213 | 
214 |             AnchorLayout:
215 |                 Label:
216 |                     text: 'transit relay'
217 | 
218 |             AnchorLayout:
219 |                 TextInput:
220 |                     id: transit_relay
221 |                     multiline: False
222 |                     size_hint: 0.8, None
223 | 
224 |             AnchorLayout:
225 |                 Button:
226 |                     text: 'reset'
227 |                     on_release: root.reset_field('transit_relay')
228 | 
229 |         BoxLayout:
230 |             orientation: 'horizontal'
231 | 
232 |             AnchorLayout:
233 |                 Button:
234 |                     text: 'cancel'
235 |                     on_release: root.manager.current = 'home_screen'
236 | 
237 |             AnchorLayout:
238 |                 Button:
239 |                     text: 'save'
240 |                     on_release: root.update_config(); root.manager.current = 'home_screen'
241 | 


--------------------------------------------------------------------------------
/src/main.py:
--------------------------------------------------------------------------------
  1 | import os
  2 | 
  3 | import humanize
  4 | from kivy.app import App
  5 | from kivy.core.clipboard import Clipboard
  6 | from kivy.core.window import Window
  7 | from kivy.factory import Factory
  8 | from kivy.properties import BooleanProperty, ObjectProperty, StringProperty
  9 | from kivy.support import install_twisted_reactor
 10 | from kivy.uix.popup import Popup
 11 | from kivy.uix.screenmanager import NoTransition, Screen, ScreenManager
 12 | from plyer import filechooser
 13 | from twisted.python.failure import Failure
 14 | 
 15 | install_twisted_reactor()
 16 | 
 17 | from config import ConfigMixin, get_config
 18 | from magic import Wormhole
 19 | from cross import (
 20 |     ensure_storage_perms, get_downloads_dir, intent_hander, open_file
 21 | )
 22 | 
 23 | 
 24 | class ErrorPopup(Popup):
 25 |     title = StringProperty('Error')
 26 |     message = StringProperty('Something bad happened!')
 27 | 
 28 |     @staticmethod
 29 |     def show(error):
 30 |         """
 31 |         Open a popup with a (hopefully) user-friendly error message.
 32 | 
 33 |         The given argument can be either an Exception, or a Twisted Failure, or
 34 |         the error message itself as a string.
 35 |         """
 36 |         if isinstance(error, Failure):
 37 |             error = error.value
 38 | 
 39 |         message = str(error)
 40 | 
 41 |         if hasattr(error, 'verbose_name'):
 42 |             title = error.verbose_name
 43 |         else:
 44 |             title = 'Error'
 45 | 
 46 |         Factory.ErrorPopup(title=title, message=message).open()
 47 | 
 48 | 
 49 | class HomeScreen(Screen):
 50 |     pass
 51 | 
 52 | 
 53 | class SendScreen(Screen):
 54 |     send_button_text = StringProperty('send')
 55 |     send_button_disabled = BooleanProperty(False)
 56 | 
 57 |     has_code = BooleanProperty(False)
 58 |     code = StringProperty('…')
 59 | 
 60 |     file_name = StringProperty('…')
 61 |     file_size = StringProperty('…')
 62 |     transferred = StringProperty('…')
 63 | 
 64 |     def on_pre_enter(self):
 65 |         """
 66 |         Reset the labels and buttons and init a magic wormhole instance.
 67 | 
 68 |         This method is called just before the user enters this screen.
 69 |         """
 70 |         self.send_button_disabled = True
 71 |         self.send_button_text = 'waiting for code'
 72 | 
 73 |         self.has_code = False
 74 |         self.code = '…'
 75 | 
 76 |         self.file_path = None
 77 |         self.file_name = '…'
 78 |         self.file_size = '…'
 79 | 
 80 |         self.bytes_transferred = 0
 81 |         self.transferred = '…'
 82 | 
 83 |         try:
 84 |             self.wormhole = Wormhole(**get_config())
 85 |         except Exception as error:
 86 |             return ErrorPopup.show(error)
 87 | 
 88 |         def update_code(code):
 89 |             self.has_code = True
 90 |             self.code = code
 91 |             self.send_button_disabled = False
 92 |             self.send_button_text = 'send'
 93 |             Clipboard.copy(code)
 94 | 
 95 |         deferred = self.wormhole.generate_code()
 96 |         deferred.addCallbacks(update_code, ErrorPopup.show)
 97 | 
 98 |     def set_file(self, path):
 99 |         """
100 |         Set the file to be sent down the wormhole.
101 | 
102 |         This method is called when the the user selects the file to send using
103 |         the file chooser. It is also called directly by the App instance when
104 |         the app has been started or resumed via a send file intent on Android.
105 |         """
106 |         try:
107 |             path = os.path.normpath(path)
108 |             assert os.path.exists(path) and os.path.isfile(path)
109 |         except:
110 |             ErrorPopup.show((
111 |                 'There is something wrong about the file you chose. '
112 |                 'One possible reason is an issue with some Androids '
113 |                 'where a file cannot be directly selected from the '
114 |                 '"Downloads" section and instead you have to reach it '
115 |                 'some other way, e.g. "Phone" -> "Downloads".'
116 |             ))
117 |             self.file_path = None
118 |             self.file_name = '…'
119 |             self.file_size = '…'
120 |         else:
121 |             self.file_path = path
122 |             self.file_name = os.path.basename(self.file_path)
123 |             self.file_size = humanize.naturalsize(
124 |                 os.stat(self.file_path).st_size
125 |             )
126 | 
127 |     def open_file_chooser(self):
128 |         """
129 |         Open a file chooser so that the user can select a file to send down the
130 |         wormhole. On Android, this could be preceded by asking for permissions.
131 | 
132 |         This method is called when the user releases the "choose file" button.
133 |         """
134 |         def handle_selection(selection):
135 |             if selection:
136 |                 self.set_file(selection[0])
137 | 
138 |         def show_error():
139 |             ErrorPopup.show((
140 |                 'You cannot send a file if the app cannot access it.'
141 |             ))
142 | 
143 |         @ensure_storage_perms(show_error)
144 |         def open_file_chooser():
145 |             filechooser.open_file(
146 |                 title='Choose a file to send',
147 |                 on_selection=handle_selection
148 |             )
149 | 
150 |         open_file_chooser()
151 | 
152 |     def send(self):
153 |         """
154 |         Send the selected file down the wormhole.
155 | 
156 |         This method is called when the user releases the send button.
157 |         """
158 |         if not self.file_path:
159 |             return ErrorPopup.show('Please choose a file to send.')
160 | 
161 |         def exchange_keys():
162 |             self.send_button_disabled = True
163 |             self.send_button_text = 'exchanging keys'
164 |             deferred = self.wormhole.exchange_keys(timeout=600)
165 |             deferred.addCallbacks(send_file, ErrorPopup.show)
166 | 
167 |         def send_file(verifier):
168 |             self.send_button_disabled = True
169 |             self.send_button_text = 'sending file'
170 |             deferred = self.wormhole.send_file(self.file_path, on_chunk)
171 |             deferred.addCallbacks(show_done, ErrorPopup.show)
172 | 
173 |         def on_chunk(chunk):
174 |             self.bytes_transferred += len(chunk)
175 |             self.transferred = humanize.naturalsize(self.bytes_transferred)
176 | 
177 |         def show_done(hex_digest):
178 |             self.send_button_disabled = True
179 |             self.send_button_text = 'done'
180 | 
181 |         exchange_keys()
182 | 
183 |     def on_leave(self):
184 |         """
185 |         Close the magic wormhole instance, if this exists and is still open.
186 | 
187 |         This method is called when the user leaves this screen.
188 |         """
189 |         try:
190 |             self.wormhole.close()
191 |         except:
192 |             pass  # opening the wormhole failed altogether
193 | 
194 | 
195 | class ReceiveScreen(Screen):
196 |     connect_button_disabled = BooleanProperty(False)
197 |     connect_button_text = StringProperty('connect')
198 | 
199 |     accept_button_disabled = BooleanProperty(True)
200 |     accept_button_func = ObjectProperty(None)
201 |     accept_button_text = StringProperty('waiting for offer')
202 | 
203 |     file_name = StringProperty('…')
204 |     file_size = StringProperty('…')
205 |     transferred = StringProperty('…')
206 | 
207 |     def on_pre_enter(self):
208 |         """
209 |         Called just before the user enters this screen.
210 |         """
211 |         self.downloads_dir = get_downloads_dir()
212 | 
213 |         self.connect_button_disabled = False
214 |         self.connect_button_text = 'connect'
215 | 
216 |         self.accept_button_disabled = True
217 |         self.accept_button_func = self.accept_offer
218 |         self.accept_button_text = 'waiting for offer'
219 | 
220 |         self.file_name = '…'
221 |         self.file_size = '…'
222 | 
223 |         self.bytes_transferred = 0
224 |         self.transferred = '…'
225 | 
226 |         self.ids.code_input.text = ''
227 | 
228 |     def open_wormhole(self):
229 |         """
230 |         Called when the user releases the connect button.
231 |         """
232 |         code = self.ids.code_input.text.strip()
233 |         code = '-'.join(code.split())
234 |         if not code:
235 |             return ErrorPopup.show('Please enter a code.')
236 | 
237 |         def connect():
238 |             self.connect_button_disabled = True
239 |             self.connect_button_text = 'connecting'
240 | 
241 |             try:
242 |                 self.wormhole = Wormhole(**get_config())
243 |             except Exception as error:
244 |                 return ErrorPopup.show(error)
245 | 
246 |             deferred = self.wormhole.connect(code)
247 |             deferred.addCallbacks(exchange_keys, ErrorPopup.show)
248 | 
249 |         def exchange_keys(code):
250 |             self.connect_button_disabled = True
251 |             self.connect_button_text = 'exchanging keys'
252 | 
253 |             deferred = self.wormhole.exchange_keys()
254 |             deferred.addCallbacks(await_offer, ErrorPopup.show)
255 | 
256 |         def await_offer(verifier):
257 |             self.connect_button_disabled = True
258 |             self.connect_button_text = 'connected'
259 | 
260 |             deferred = self.wormhole.await_offer()
261 |             deferred.addCallbacks(show_offer, ErrorPopup.show)
262 | 
263 |         def show_offer(offer):
264 |             self.file_name = str(offer['filename'])
265 |             self.file_size = humanize.naturalsize(offer['filesize'])
266 | 
267 |             self.accept_button_disabled = False
268 |             self.accept_button_text = 'accept'
269 | 
270 |         connect()
271 | 
272 |     def accept_offer(self):
273 |         """
274 |         Called when the user releases the accept button.
275 |         """
276 |         file_path = os.path.join(self.downloads_dir, self.file_name)
277 | 
278 |         def show_error():
279 |             ErrorPopup.show((
280 |                 'You cannot receive a file if the app cannot write it.'
281 |             ))
282 | 
283 |         @ensure_storage_perms(show_error)
284 |         def accept_offer():
285 |             self.accept_button_disabled = True
286 |             self.accept_button_text = 'receiving'
287 | 
288 |             deferred = self.wormhole.accept_offer(file_path, on_chunk)
289 |             deferred.addCallbacks(show_done, ErrorPopup.show)
290 | 
291 |         def on_chunk(chunk):
292 |             self.bytes_transferred += len(chunk)
293 |             self.transferred = humanize.naturalsize(self.bytes_transferred)
294 | 
295 |         def show_done(hex_digest):
296 |             self.accept_button_disabled = False
297 |             self.accept_button_func = self.open_file
298 |             self.accept_button_text = 'open file'
299 | 
300 |         accept_offer()
301 | 
302 |     def open_file(self):
303 |         """
304 |         Called when the user presses the accept button after the file transfer
305 |         has been completed.
306 |         """
307 |         file_path = os.path.join(self.downloads_dir, self.file_name)
308 | 
309 |         def show_error():
310 |             ErrorPopup.show('Cannot open {}'.format(file_path))
311 | 
312 |         @ensure_storage_perms(show_error)
313 |         def do():
314 |             open_file(file_path)
315 | 
316 |         if os.path.exists(file_path):
317 |             do()
318 |         else:
319 |             show_error()
320 | 
321 |     def on_leave(self):
322 |         """
323 |         Called when the user leaves this screen.
324 |         """
325 |         try:
326 |             self.wormhole.close()
327 |         except AttributeError:
328 |             pass
329 | 
330 | 
331 | class WormholeApp(ConfigMixin, App):
332 | 
333 |     def build(self):
334 |         """
335 |         Init and return the main widget, in our case the screen manager.
336 | 
337 |         Attach the on_keyboard event listener to the Window object.
338 |         """
339 |         self.screen_manager = ScreenManager(transition=NoTransition())
340 | 
341 |         for screen_cls in [HomeScreen, SendScreen, ReceiveScreen]:
342 |             self.screen_manager.add_widget(screen_cls())
343 | 
344 |         Window.bind(on_keyboard=self.on_keyboard)
345 | 
346 |         return self.screen_manager
347 | 
348 |     def on_keyboard(self, window, key, *args):
349 |         """
350 |         Called when the keyboard is used for input.
351 | 
352 |         Handle the back button on Android (this equates to the escape key). If
353 |         the user is not on the home screen, navigate them there; otherwise let
354 |         them exit the app (the default behaviour).
355 |         """
356 |         if key == 27:
357 |             if self.screen_manager.current != 'home_screen':
358 |                 self.screen_manager.current = 'home_screen'
359 |                 return True
360 | 
361 |         return False
362 | 
363 |     def on_start(self):
364 |         """
365 |         Called when the app first starts running, after self.build().
366 | 
367 |         If on Android, check whether the app activity has been started via an
368 |         intent to send a file, and if yes, set the screen accordingly.
369 |         """
370 |         try:
371 |             file_path = intent_hander.pop()
372 |         except ValueError as error:
373 |             ErrorPopup.show(error)
374 |         else:
375 |             if file_path is not None:
376 |                 self.screen_manager.current = 'send_screen'
377 |                 self.screen_manager.current_screen.set_file(file_path)
378 | 
379 |     def on_resume(self):
380 |         """
381 |         Called when the app comes back to the foreground.
382 | 
383 |         As it is the case with on_start, check if on Android the app has been
384 |         started via an intent and set the screen accordingly.
385 |         """
386 |         self.on_start()
387 | 
388 | 
389 | if __name__ == '__main__':
390 |     WormholeApp().run()
391 | 


--------------------------------------------------------------------------------
/src/magic.py:
--------------------------------------------------------------------------------
  1 | import hashlib
  2 | import json
  3 | import os
  4 | 
  5 | import wormhole.errors
  6 | from twisted.internet import reactor
  7 | from twisted.internet.defer import inlineCallbacks, returnValue, TimeoutError
  8 | from twisted.protocols.basic import FileSender
  9 | from wormhole import create
 10 | from wormhole.cli.cmd_send import APPID
 11 | from wormhole.cli.public_relay import RENDEZVOUS_RELAY, TRANSIT_RELAY
 12 | from wormhole.transit import TransitReceiver, TransitSender
 13 | 
 14 | 
 15 | class ConnectionError(Exception):
 16 |     """
 17 |     Raised when our client cannot establish connection to the rendezvous or the
 18 |     transit relay servers.
 19 |     """
 20 |     verbose_name = 'Connection error'
 21 | 
 22 | 
 23 | class HumanError(Exception):
 24 |     """
 25 |     Raised when one of the humans at either end of the wormhole does something
 26 |     that breaks it, e.g. enters the wrong code.
 27 |     """
 28 |     verbose_name = 'Possible human error'
 29 | 
 30 | 
 31 | class SuspiciousOperation(Exception):
 32 |     """
 33 |     Raised when things do not go according to the protocol, e.g. a message that
 34 |     cannot be parsed is received.
 35 |     """
 36 |     verbose_name = 'Suspicious operation'
 37 | 
 38 | 
 39 | class Timeout(Exception):
 40 |     """
 41 |     Raised when the rendezvous server or the other end of the wormhole take
 42 |     longer than expected to respond.
 43 |     """
 44 |     verbose_name = 'Timeout'
 45 | 
 46 | 
 47 | class TransferError(Exception):
 48 |     """
 49 |     Raised when the file transfer failed, e.g. the connection drops before all
 50 |     the bytes have been transferred.
 51 |     """
 52 |     verbose_name = 'Transfer error'
 53 | 
 54 | 
 55 | class Wormhole:
 56 |     """
 57 |     Wrapper around magic wormhole's code that makes it easier to reason about
 58 |     what is going on, at least for me. Usage for sending files:
 59 | 
 60 |         wormhole = Wormhole()
 61 |         code = yield wormhole.generate_code()
 62 |         verifier = yield wormhole.exchange_keys()
 63 |         hex_digest = yield wormhole.send_file(file_path)
 64 | 
 65 |     Usage for receiving files:
 66 | 
 67 |         wormhole = Wormhole()
 68 |         code = yield wormhole.connect(code)
 69 |         verifier = yield wormhole.exchange_keys()
 70 |         offer = yield wormhole.await_offer()
 71 |         hex_digest = yield wormhole.accept_offer(file_path)
 72 | 
 73 |     Almost all methods return Deferred instances that either resolve into the
 74 |     respective value (e.g. the generated code) or reject with one of the four
 75 |     errors defined above.
 76 |     """
 77 | 
 78 |     def __init__(
 79 |             self, app_id=APPID, rendezvous_relay=RENDEZVOUS_RELAY,
 80 |             transit_relay=TRANSIT_RELAY
 81 |         ):
 82 |         """
 83 |         Create a magic wormhole.
 84 |         """
 85 |         self.app_id = app_id
 86 |         self.rendezvous_relay = rendezvous_relay
 87 |         self.transit_relay = transit_relay
 88 | 
 89 |         try:
 90 |             self.wormhole = create(self.app_id, self.rendezvous_relay, reactor)
 91 |         except Exception:
 92 |             raise ConnectionError((
 93 |                 'Cannot connect to the rendezvous server. '
 94 |                 'In case you are not using the default server, '
 95 |                 'you can double-check the URL in the config.'
 96 |             ))
 97 | 
 98 |         self.offer = None
 99 |         self.transit = None
100 | 
101 |     @inlineCallbacks
102 |     def generate_code(self, timeout=10):
103 |         """
104 |         Generate the code that the users at the two ends of the wormhole will
105 |         have to exchange.
106 | 
107 |         Return a Deferred that resolves into the code.
108 |         """
109 |         self.wormhole.allocate_code()
110 | 
111 |         deferred = self.wormhole.get_code()
112 |         deferred.addTimeout(timeout, reactor)
113 | 
114 |         try:
115 |             code = yield deferred
116 |         except wormhole.errors.ServerConnectionError:
117 |             raise ConnectionError((
118 |                 'The rendezvous server cannot be reached. '
119 |                 'Please double-check your Internet connection.'
120 |             ))
121 |         except TimeoutError:
122 |             raise Timeout('The rendezvous server timed out.')
123 | 
124 |         return returnValue(code)
125 | 
126 |     @inlineCallbacks
127 |     def connect(self, code, timeout=10):
128 |         """
129 |         Connect to another wormhole client by its code generated. This has to
130 |         be exchanged between the two users before the wormhole connects.
131 | 
132 |         Return a Deferred that resolves upon successful connection.
133 |         """
134 |         self.wormhole.set_code(code)
135 | 
136 |         deferred = self.wormhole.get_code()
137 |         deferred.addTimeout(timeout, reactor)
138 | 
139 |         try:
140 |             code = yield deferred
141 |         except TimeoutError:
142 |             raise Timeout('The rendezvous server timed out.')
143 | 
144 |         return returnValue(code)
145 | 
146 |     @inlineCallbacks
147 |     def exchange_keys(self, timeout=10):
148 |         """
149 |         Return a Deferred that resolves when the key exchange between the two
150 |         clients has been completed.
151 | 
152 |         The Deferred resolves into the so-called verifier, a hash of the shared
153 |         key, which can be compared by the users at both ends of the wormhole in
154 |         order to make sure no man-in-the-middle attack is taking place.
155 |         """
156 |         deferred = self.wormhole.get_verifier()
157 |         deferred.addTimeout(timeout, reactor)
158 | 
159 |         try:
160 |             verifier = yield deferred
161 |         except TimeoutError:
162 |             raise Timeout('The key exchange with the other side timed out.')
163 |         except wormhole.errors.WrongPasswordError:
164 |             raise HumanError((
165 |                 'The key exchange with the other side failed. '
166 |                 'The most probable cause for this is mistyping the code.'
167 |             ))
168 | 
169 |         return returnValue(verifier)
170 | 
171 |     def send_json(self, message):
172 |         """
173 |         Send a JSON message down the wormhole.
174 |         """
175 |         self.wormhole.send_message(bytes(json.dumps(message), 'utf-8'))
176 | 
177 |     @inlineCallbacks
178 |     def await_json(self, timeout=600):
179 |         """
180 |         Return a Deferred that resolves into the next JSON message that comes
181 |         out of the wormhole.
182 |         """
183 |         deferred = self.wormhole.get_message()
184 |         deferred.addTimeout(timeout, reactor)
185 | 
186 |         try:
187 |             message = yield deferred
188 |             message = json.loads(str(message, 'utf-8'))
189 |         except TimeoutError:
190 |             raise Timeout((
191 |                 'The message exchange with the other side timed out.'
192 |             ))
193 |         except:
194 |             raise SuspiciousOperation((
195 |                 'The other side sent a badly formatted message.'
196 |             ))
197 | 
198 |         return returnValue(message)
199 | 
200 |     @inlineCallbacks
201 |     def send_file(self, file_path, on_chunk):
202 |         """
203 |         Send a file down the wormhole. As per the file-transfer protocol this
204 |         involves the following steps:
205 | 
206 |         - send a message with the details needed for establishing the transit;
207 |         - send a message with the offer, i.e. the name and size of the file;
208 |         - run a loop waiting for the response(s) of the other end.
209 | 
210 |         Return a Deferred that resolves when the file has been transferred.
211 |         """
212 |         assert self.transit is None and os.path.exists(file_path)
213 | 
214 |         self.transit = TransitSender(self.transit_relay)
215 | 
216 |         try:
217 |             our_hints = yield self.transit.get_connection_hints()
218 |             our_abilities = self.transit.get_connection_abilities()
219 |         except Exception:
220 |             raise ConnectionError((
221 |                 'Cannot connect to the transit relay. '
222 |                 'In case you are not using the default server, '
223 |                 'you can double-check the URL in the config.'
224 |             ))
225 | 
226 |         self.send_json({
227 |             'transit': {
228 |                 'abilities-v1': our_abilities,
229 |                 'hints-v1': our_hints,
230 |             }
231 |         })
232 | 
233 |         self.send_json({
234 |             'offer': {
235 |                 'file': {
236 |                     'filename': os.path.basename(file_path),
237 |                     'filesize': os.stat(file_path).st_size
238 |                 }
239 |             }
240 |         })
241 | 
242 |         while True:
243 |             message = yield self.await_json()
244 | 
245 |             if 'error' in message:
246 |                 yield self.close()
247 |                 raise SuspiciousOperation(str(message['error']))
248 | 
249 |             if 'transit' in message:
250 |                 self.transit.add_connection_hints(
251 |                     message['transit']['hints-v1']
252 |                 )
253 | 
254 |                 transit_key = self.wormhole.derive_key(
255 |                     '{}/transit-key'.format(self.app_id),
256 |                     self.transit.TRANSIT_KEY_LENGTH
257 |                 )
258 |                 self.transit.set_transit_key(transit_key)
259 | 
260 |             if 'answer' in message:
261 |                 try:
262 |                     assert message['answer']['file_ack'] == 'ok'
263 |                 except (AssertionError, KeyError):
264 |                     raise HumanError('The other side declined the file.')
265 |                 else:
266 |                     hex_digest = yield self.transfer_file(file_path, on_chunk)
267 |                     return returnValue(hex_digest)
268 | 
269 |     @inlineCallbacks
270 |     def transfer_file(self, file_path, on_chunk):
271 |         """
272 |         Send a file via the transit. Assume that the latter has been already
273 |         established. If the other end provides a hash when done, check it.
274 | 
275 |         Helper for the send_file method above.
276 |         """
277 |         record_pipe = yield self.transit.connect()
278 |         hasher = hashlib.sha256()
279 | 
280 |         def transform(data):
281 |             hasher.update(data)
282 |             on_chunk(data)
283 |             return data
284 | 
285 |         with open(file_path, 'rb') as f:
286 |             file_sender = FileSender()
287 |             yield file_sender.beginFileTransfer(f, record_pipe, transform)
288 | 
289 |         ack_record = yield record_pipe.receive_record()
290 |         ack_record = json.loads(str(ack_record, 'utf-8'))
291 | 
292 |         yield record_pipe.close()
293 | 
294 |         try:
295 |             assert ack_record['ack'] == 'ok'
296 |             if ack_record['sha256']:
297 |                 assert ack_record['sha256'] == hasher.hexdigest()
298 |         except (AssertionError, KeyError):
299 |             raise TransferError('The file transfer failed.')
300 | 
301 |         return returnValue(hasher.hexdigest())
302 | 
303 |     @inlineCallbacks
304 |     def await_offer(self):
305 |         """
306 |         Start waiting for the other end of the wormhole to send a file offer.
307 | 
308 |         As per the file-transfer protocol this involves running a loop waiting
309 |         for both transit details and the offer itself. The transit should be
310 |         already established when the incoming file offer is processed.
311 | 
312 |         Return a Deferred that resolves into a {filename, filesize} dict.
313 |         """
314 |         assert self.transit is None
315 | 
316 |         self.transit = TransitReceiver(self.transit_relay)
317 | 
318 |         transit_key = self.wormhole.derive_key(
319 |             '{}/transit-key'.format(self.app_id),
320 |             self.transit.TRANSIT_KEY_LENGTH
321 |         )
322 |         self.transit.set_transit_key(transit_key)
323 | 
324 |         while True:
325 |             message = yield self.await_json()
326 | 
327 |             if 'error' in message:
328 |                 yield self.close()
329 |                 raise SuspiciousOperation(str(message['error']))
330 | 
331 |             if 'transit' in message:
332 |                 self.transit.add_connection_hints(
333 |                     message['transit']['hints-v1']
334 |                 )
335 | 
336 |                 try:
337 |                     our_hints = yield self.transit.get_connection_hints()
338 |                     our_abilities = self.transit.get_connection_abilities()
339 |                 except Exception:
340 |                     raise ConnectionError((
341 |                         'Cannot connect to the transit relay. '
342 |                         'In case you are not using the default server, '
343 |                         'you can double-check the URL in the config.'
344 |                     ))
345 | 
346 |                 self.send_json({
347 |                     'transit': {
348 |                         'abilities-v1': our_abilities,
349 |                         'hints-v1': our_hints,
350 |                     }
351 |                 })
352 | 
353 |             if 'offer' in message:
354 |                 self.offer = message['offer']
355 |                 return returnValue(self.offer['file'])
356 | 
357 |     @inlineCallbacks
358 |     def accept_offer(self, file_path, on_chunk):
359 |         """
360 |         Download the file sent by the other end and write it to the specified
361 |         location. Assume that the transit has been already established.
362 | 
363 |         Return a Deferred that resolves into the hex digest of the transferred
364 |         data once the download is completed.
365 |         """
366 |         assert self.offer and self.transit
367 | 
368 |         size = self.offer['file']['filesize']
369 |         self.offer = None
370 | 
371 |         self.send_json({'answer': {'file_ack': 'ok'}})
372 | 
373 |         record_pipe = yield self.transit.connect()
374 |         hasher = hashlib.sha256()
375 | 
376 |         def callback(data):
377 |             hasher.update(data)
378 |             on_chunk(data)
379 | 
380 |         with open(file_path, 'wb') as f:
381 |             received = yield record_pipe.writeToFile(
382 |                 f, size, progress=None, hasher=callback
383 |             )
384 | 
385 |             if received != size:
386 |                 raise TransferError('The download could not be completed.')
387 | 
388 |         ack_record = {'ack': 'ok', 'sha256': hasher.hexdigest()}
389 |         ack_record = bytes(json.dumps(ack_record), 'utf-8')
390 |         yield record_pipe.send_record(ack_record)
391 | 
392 |         yield record_pipe.close()
393 | 
394 |         return returnValue(hasher.hexdigest())
395 | 
396 |     def close(self):
397 |         """
398 |         Close the wormhole.
399 | 
400 |         Return a Deferred that resolves into the string "happy" when done or
401 |         rejects with one of the following errors: WelcomeError, ServerError,
402 |         LonelyError, WrongPasswordError [1].
403 | 
404 |         [1]: https://magic-wormhole.readthedocs.io/en/latest/api.html#closing
405 |         """
406 |         deferred = self.wormhole.close()
407 |         return deferred
408 | 


--------------------------------------------------------------------------------
/COPYING:
--------------------------------------------------------------------------------
  1 |                     GNU GENERAL PUBLIC LICENSE
  2 |                        Version 3, 29 June 2007
  3 | 
  4 |  Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
  5 |  Everyone is permitted to copy and distribute verbatim copies
  6 |  of this license document, but changing it is not allowed.
  7 | 
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 11 | software and other kinds of works.
 12 | 
 13 |   The licenses for most software and other practical works are designed
 14 | to take away your freedom to share and change the works.  By contrast,
 15 | the GNU General Public License is intended to guarantee your freedom to
 16 | share and change all versions of a program--to make sure it remains free
 17 | software for all its users.  We, the Free Software Foundation, use the
 18 | GNU General Public License for most of our software; it applies also to
 19 | any other work released this way by its authors.  You can apply it to
 20 | your programs, too.
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182 | measure under any applicable law fulfilling obligations under article
183 | 11 of the WIPO copyright treaty adopted on 20 December 1996, or
184 | similar laws prohibiting or restricting circumvention of such
185 | measures.
186 | 
187 |   When you convey a covered work, you waive any legal power to forbid
188 | circumvention of technological measures to the extent such circumvention
189 | is effected by exercising rights under this License with respect to
190 | the covered work, and you disclaim any intention to limit operation or
191 | modification of the work as a means of enforcing, against the work's
192 | users, your or third parties' legal rights to forbid circumvention of
193 | technological measures.
194 | 
195 |   4. Conveying Verbatim Copies.
196 | 
197 |   You may convey verbatim copies of the Program's source code as you
198 | receive it, in any medium, provided that you conspicuously and
199 | appropriately publish on each copy an appropriate copyright notice;
200 | keep intact all notices stating that this License and any
201 | non-permissive terms added in accord with section 7 apply to the code;
202 | keep intact all notices of the absence of any warranty; and give all
203 | recipients a copy of this License along with the Program.
204 | 
205 |   You may charge any price or no price for each copy that you convey,
206 | and you may offer support or warranty protection for a fee.
207 | 
208 |   5. Conveying Modified Source Versions.
209 | 
210 |   You may convey a work based on the Program, or the modifications to
211 | produce it from the Program, in the form of source code under the
212 | terms of section 4, provided that you also meet all of these conditions:
213 | 
214 |     a) The work must carry prominent notices stating that you modified
215 |     it, and giving a relevant date.
216 | 
217 |     b) The work must carry prominent notices stating that it is
218 |     released under this License and any conditions added under section
219 |     7.  This requirement modifies the requirement in section 4 to
220 |     "keep intact all notices".
221 | 
222 |     c) You must license the entire work, as a whole, under this
223 |     License to anyone who comes into possession of a copy.  This
224 |     License will therefore apply, along with any applicable section 7
225 |     additional terms, to the whole of the work, and all its parts,
226 |     regardless of how they are packaged.  This License gives no
227 |     permission to license the work in any other way, but it does not
228 |     invalidate such permission if you have separately received it.
229 | 
230 |     d) If the work has interactive user interfaces, each must display
231 |     Appropriate Legal Notices; however, if the Program has interactive
232 |     interfaces that do not display Appropriate Legal Notices, your
233 |     work need not make them do so.
234 | 
235 |   A compilation of a covered work with other separate and independent
236 | works, which are not by their nature extensions of the covered work,
237 | and which are not combined with it such as to form a larger program,
238 | in or on a volume of a storage or distribution medium, is called an
239 | "aggregate" if the compilation and its resulting copyright are not
240 | used to limit the access or legal rights of the compilation's users
241 | beyond what the individual works permit.  Inclusion of a covered work
242 | in an aggregate does not cause this License to apply to the other
243 | parts of the aggregate.
244 | 
245 |   6. Conveying Non-Source Forms.
246 | 
247 |   You may convey a covered work in object code form under the terms
248 | of sections 4 and 5, provided that you also convey the
249 | machine-readable Corresponding Source under the terms of this License,
250 | in one of these ways:
251 | 
252 |     a) Convey the object code in, or embodied in, a physical product
253 |     (including a physical distribution medium), accompanied by the
254 |     Corresponding Source fixed on a durable physical medium
255 |     customarily used for software interchange.
256 | 
257 |     b) Convey the object code in, or embodied in, a physical product
258 |     (including a physical distribution medium), accompanied by a
259 |     written offer, valid for at least three years and valid for as
260 |     long as you offer spare parts or customer support for that product
261 |     model, to give anyone who possesses the object code either (1) a
262 |     copy of the Corresponding Source for all the software in the
263 |     product that is covered by this License, on a durable physical
264 |     medium customarily used for software interchange, for a price no
265 |     more than your reasonable cost of physically performing this
266 |     conveying of source, or (2) access to copy the
267 |     Corresponding Source from a network server at no charge.
268 | 
269 |     c) Convey individual copies of the object code with a copy of the
270 |     written offer to provide the Corresponding Source.  This
271 |     alternative is allowed only occasionally and noncommercially, and
272 |     only if you received the object code with such an offer, in accord
273 |     with subsection 6b.
274 | 
275 |     d) Convey the object code by offering access from a designated
276 |     place (gratis or for a charge), and offer equivalent access to the
277 |     Corresponding Source in the same way through the same place at no
278 |     further charge.  You need not require recipients to copy the
279 |     Corresponding Source along with the object code.  If the place to
280 |     copy the object code is a network server, the Corresponding Source
281 |     may be on a different server (operated by you or a third party)
282 |     that supports equivalent copying facilities, provided you maintain
283 |     clear directions next to the object code saying where to find the
284 |     Corresponding Source.  Regardless of what server hosts the
285 |     Corresponding Source, you remain obligated to ensure that it is
286 |     available for as long as needed to satisfy these requirements.
287 | 
288 |     e) Convey the object code using peer-to-peer transmission, provided
289 |     you inform other peers where the object code and Corresponding
290 |     Source of the work are being offered to the general public at no
291 |     charge under subsection 6d.
292 | 
293 |   A separable portion of the object code, whose source code is excluded
294 | from the Corresponding Source as a System Library, need not be
295 | included in conveying the object code work.
296 | 
297 |   A "User Product" is either (1) a "consumer product", which means any
298 | tangible personal property which is normally used for personal, family,
299 | or household purposes, or (2) anything designed or sold for incorporation
300 | into a dwelling.  In determining whether a product is a consumer product,
301 | doubtful cases shall be resolved in favor of coverage.  For a particular
302 | product received by a particular user, "normally used" refers to a
303 | typical or common use of that class of product, regardless of the status
304 | of the particular user or of the way in which the particular user
305 | actually uses, or expects or is expected to use, the product.  A product
306 | is a consumer product regardless of whether the product has substantial
307 | commercial, industrial or non-consumer uses, unless such uses represent
308 | the only significant mode of use of the product.
309 | 
310 |   "Installation Information" for a User Product means any methods,
311 | procedures, authorization keys, or other information required to install
312 | and execute modified versions of a covered work in that User Product from
313 | a modified version of its Corresponding Source.  The information must
314 | suffice to ensure that the continued functioning of the modified object
315 | code is in no case prevented or interfered with solely because
316 | modification has been made.
317 | 
318 |   If you convey an object code work under this section in, or with, or
319 | specifically for use in, a User Product, and the conveying occurs as
320 | part of a transaction in which the right of possession and use of the
321 | User Product is transferred to the recipient in perpetuity or for a
322 | fixed term (regardless of how the transaction is characterized), the
323 | Corresponding Source conveyed under this section must be accompanied
324 | by the Installation Information.  But this requirement does not apply
325 | if neither you nor any third party retains the ability to install
326 | modified object code on the User Product (for example, the work has
327 | been installed in ROM).
328 | 
329 |   The requirement to provide Installation Information does not include a
330 | requirement to continue to provide support service, warranty, or updates
331 | for a work that has been modified or installed by the recipient, or for
332 | the User Product in which it has been modified or installed.  Access to a
333 | network may be denied when the modification itself materially and
334 | adversely affects the operation of the network or violates the rules and
335 | protocols for communication across the network.
336 | 
337 |   Corresponding Source conveyed, and Installation Information provided,
338 | in accord with this section must be in a format that is publicly
339 | documented (and with an implementation available to the public in
340 | source code form), and must require no special password or key for
341 | unpacking, reading or copying.
342 | 
343 |   7. Additional Terms.
344 | 
345 |   "Additional permissions" are terms that supplement the terms of this
346 | License by making exceptions from one or more of its conditions.
347 | Additional permissions that are applicable to the entire Program shall
348 | be treated as though they were included in this License, to the extent
349 | that they are valid under applicable law.  If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 | 
354 |   When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it.  (Additional permissions may be written to require their own
357 | removal in certain cases when you modify the work.)  You may place
358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 | 
361 |   Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 | 
365 |     a) Disclaiming warranty or limiting liability differently from the
366 |     terms of sections 15 and 16 of this License; or
367 | 
368 |     b) Requiring preservation of specified reasonable legal notices or
369 |     author attributions in that material or in the Appropriate Legal
370 |     Notices displayed by works containing it; or
371 | 
372 |     c) Prohibiting misrepresentation of the origin of that material, or
373 |     requiring that modified versions of such material be marked in
374 |     reasonable ways as different from the original version; or
375 | 
376 |     d) Limiting the use for publicity purposes of names of licensors or
377 |     authors of the material; or
378 | 
379 |     e) Declining to grant rights under trademark law for use of some
380 |     trade names, trademarks, or service marks; or
381 | 
382 |     f) Requiring indemnification of licensors and authors of that
383 |     material by anyone who conveys the material (or modified versions of
384 |     it) with contractual assumptions of liability to the recipient, for
385 |     any liability that these contractual assumptions directly impose on
386 |     those licensors and authors.
387 | 
388 |   All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10.  If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
392 | restriction, you may remove that term.  If a license document contains
393 | a further restriction but permits relicensing or conveying under this
394 | License, you may add to a covered work material governed by the terms
395 | of that license document, provided that the further restriction does
396 | not survive such relicensing or conveying.
397 | 
398 |   If you add terms to a covered work in accord with this section, you
399 | must place, in the relevant source files, a statement of the
400 | additional terms that apply to those files, or a notice indicating
401 | where to find the applicable terms.
402 | 
403 |   Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 | 
407 |   8. Termination.
408 | 
409 |   You may not propagate or modify a covered work except as expressly
410 | provided under this License.  Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 | 
415 |   However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
419 | holder fails to notify you of the violation by some reasonable means
420 | prior to 60 days after the cessation.
421 | 
422 |   Moreover, your license from a particular copyright holder is
423 | reinstated permanently if the copyright holder notifies you of the
424 | violation by some reasonable means, this is the first time you have
425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 | 
429 |   Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
431 | this License.  If your rights have been terminated and not permanently
432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 | 
435 |   9. Acceptance Not Required for Having Copies.
436 | 
437 |   You are not required to accept this License in order to receive or
438 | run a copy of the Program.  Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance.  However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work.  These actions infringe copyright if you do
443 | not accept this License.  Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 | 
446 |   10. Automatic Licensing of Downstream Recipients.
447 | 
448 |   Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License.  You are not responsible
451 | for enforcing compliance by third parties with this License.
452 | 
453 |   An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations.  If propagation of a covered
456 | work results from an entity transaction, each party to that
457 | transaction who receives a copy of the work also receives whatever
458 | licenses to the work the party's predecessor in interest had or could
459 | give under the previous paragraph, plus a right to possession of the
460 | Corresponding Source of the work from the predecessor in interest, if
461 | the predecessor has it or can get it with reasonable efforts.
462 | 
463 |   You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License.  For example, you may
465 | not impose a license fee, royalty, or other charge for exercise of
466 | rights granted under this License, and you may not initiate litigation
467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 | 
471 |   11. Patents.
472 | 
473 |   A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based.  The
475 | work thus licensed is called the contributor's "contributor version".
476 | 
477 |   A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version.  For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 | 
487 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
489 | make, use, sell, offer for sale, import and otherwise run, modify and
490 | propagate the contents of its contributor version.
491 | 
492 |   In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
495 | sue for patent infringement).  To "grant" such a patent license to a
496 | party means to make such an agreement or commitment not to enforce a
497 | patent against the party.
498 | 
499 |   If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
501 | to copy, free of charge and under the terms of this License, through a
502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
507 | license to downstream recipients.  "Knowingly relying" means you have
508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 | 
513 |   If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 | 
521 |   A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     <one line to give the program's name and a brief idea of what it does.>
635 |     Copyright (C) <year>  <name of author>
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <https://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     <program>  Copyright (C) <year>  <name of author>
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <https://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <https://www.gnu.org/licenses/why-not-lgpl.html>.
675 | 


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