pylightning: Implement the lightning handshake and wire protocol

Simple transcript of the specification in python :-) Signed-off-by: Christian Decker <decker.christian@gmail.com>
6 years ago · 4e0c3f098c
3 changed files with 215 additions and 1 deletions
--- a/contrib/pylightning/requirements.txt
+++ b/contrib/pylightning/requirements.txt
@ -0,0 +1,2 @@
+cryptography==2.7
+coincurve==12.0.0
--- a/contrib/pylightning/setup.py
+++ b/contrib/pylightning/setup.py
@ -6,6 +6,9 @@ import io
 with io.open('README.md', encoding='utf-8') as f:
    long_description = f.read()

+with io.open('requirements.txt', encoding='utf-8') as f:
+    requirements = [r for r in f.read().split('\n') if len(r)]
+
 setup(name='pylightning',
      version=lightning.__version__,
      description='Client library for lightningd',
@ -17,4 +20,5 @@ setup(name='pylightning',
      license='MIT',
      packages=['lightning'],
      scripts=['lightning-pay'],
-      zip_safe=True)
+      zip_safe=True,
+      install_requires=requirements)
--- a/contrib/pylightning/tests/test_wire.py
+++ b/contrib/pylightning/tests/test_wire.py
@ -0,0 +1,208 @@
+from binascii import hexlify, unhexlify
+from pyln.proto.wire import PrivateKey, PublicKey, LightningConnection
+import socket
+from pyln.proto import wire
+import threading
+
+
+def test_primitives():
+    raw_privkey = unhexlify('1111111111111111111111111111111111111111111111111111111111111111')
+    privkey = PrivateKey(raw_privkey)
+    pubkey = privkey.public_key()
+    assert(hexlify(pubkey.serializeCompressed()) == b'034f355bdcb7cc0af728ef3cceb9615d90684bb5b2ca5f859ab0f0b704075871aa')
+
+    # Now try with the raw constructor once more
+    pubkey = PublicKey(unhexlify(b'034f355bdcb7cc0af728ef3cceb9615d90684bb5b2ca5f859ab0f0b704075871aa'))
+    assert(hexlify(pubkey.serializeCompressed()) == b'034f355bdcb7cc0af728ef3cceb9615d90684bb5b2ca5f859ab0f0b704075871aa')
+
+
+def test_encrypt_decrypt():
+    """ Test encryptWithAD and decryptWithAD primitives
+    Taken from https://github.com/lightningnetwork/lightning-rfc/blob/master/08-transport.md#initiator-tests
+    """
+    inp = [
+        b'e68f69b7f096d7917245f5e5cf8ae1595febe4d4644333c99f9c4a1282031c9f',
+        b'000000000000000000000000',
+        b'9e0e7de8bb75554f21db034633de04be41a2b8a18da7a319a03c803bf02b396c',
+        b''
+    ]
+    inp = [unhexlify(i) for i in inp]
+    c = wire.encryptWithAD(*inp)
+    assert(hexlify(c) == b'0df6086551151f58b8afe6c195782c6a')
+
+    # h=0x9d1ffbb639e7e20021d9259491dc7b160aab270fb1339ef135053f6f2cebe9ce
+    inp[3] = c
+    d = wire.decryptWithAD(*inp)
+    assert(hexlify(d) == b'')
+
+
+def test_handshake():
+    """Go through the test vector step-by-step.
+    """
+    rs_privkey = PrivateKey(unhexlify('2121212121212121212121212121212121212121212121212121212121212121'))
+    rs_pubkey = rs_privkey.public_key()
+    assert(hexlify(rs_pubkey.serializeCompressed()) == b'028d7500dd4c12685d1f568b4c2b5048e8534b873319f3a8daa612b469132ec7f7')
+
+    ls_privkey = PrivateKey(unhexlify('1111111111111111111111111111111111111111111111111111111111111111'))
+    ls_pubkey = ls_privkey.public_key()
+    assert(hexlify(ls_pubkey.serializeCompressed()) == b'034f355bdcb7cc0af728ef3cceb9615d90684bb5b2ca5f859ab0f0b704075871aa')
+
+    c1, c2 = socket.socketpair()
+
+    lc1 = LightningConnection(c1, rs_pubkey, ls_privkey, is_initiator=True)
+    lc2 = LightningConnection(c2, ls_pubkey, rs_privkey, is_initiator=False)
+
+    # Override the generated ephemeral key for the test:
+    lc1.handshake['e'] = PrivateKey(unhexlify('1212121212121212121212121212121212121212121212121212121212121212'))
+    lc2.handshake['e'] = PrivateKey(unhexlify(b'2222222222222222222222222222222222222222222222222222222222222222'))
+    assert(hexlify(lc1.handshake['e'].public_key().serializeCompressed()) == b'036360e856310ce5d294e8be33fc807077dc56ac80d95d9cd4ddbd21325eff73f7')
+
+    assert(hexlify(lc1.handshake['h']) == b'8401b3fdcaaa710b5405400536a3d5fd7792fe8e7fe29cd8b687216fe323ecbd')
+    assert(lc1.handshake['h'] == lc2.handshake['h'])
+    m = lc1.handshake_act_one_initiator()
+    assert(hexlify(m) == b'00036360e856310ce5d294e8be33fc807077dc56ac80d95d9cd4ddbd21325eff73f70df6086551151f58b8afe6c195782c6a')
+
+    lc2.handshake_act_one_responder(m)
+    assert(hexlify(lc1.handshake['h']) == b'9d1ffbb639e7e20021d9259491dc7b160aab270fb1339ef135053f6f2cebe9ce')
+    assert(hexlify(lc1.handshake['h']) == hexlify(lc2.handshake['h']))
+
+    assert(hexlify(lc1.chaining_key) == b'b61ec1191326fa240decc9564369dbb3ae2b34341d1e11ad64ed89f89180582f')
+    assert(hexlify(lc2.chaining_key) == b'b61ec1191326fa240decc9564369dbb3ae2b34341d1e11ad64ed89f89180582f')
+
+    m = lc2.handshake_act_two_responder()
+    assert(hexlify(m) == b'0002466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f276e2470b93aac583c9ef6eafca3f730ae')
+    assert(hexlify(lc2.handshake['h']) == b'90578e247e98674e661013da3c5c1ca6a8c8f48c90b485c0dfa1494e23d56d72')
+
+    lc1.handshake_act_two_initiator(m)
+    assert(hexlify(lc1.handshake['h']) == b'90578e247e98674e661013da3c5c1ca6a8c8f48c90b485c0dfa1494e23d56d72')
+
+    assert(hexlify(lc1.chaining_key) == b'e89d31033a1b6bf68c07d22e08ea4d7884646c4b60a9528598ccb4ee2c8f56ba')
+    assert(hexlify(lc2.chaining_key) == b'e89d31033a1b6bf68c07d22e08ea4d7884646c4b60a9528598ccb4ee2c8f56ba')
+
+    m = lc1.handshake_act_three_initiator()
+    assert(hexlify(m) == b'00b9e3a702e93e3a9948c2ed6e5fd7590a6e1c3a0344cfc9d5b57357049aa22355361aa02e55a8fc28fef5bd6d71ad0c38228dc68b1c466263b47fdf31e560e139ba')
+    assert(hexlify(lc1.sk) == b'969ab31b4d288cedf6218839b27a3e2140827047f2c0f01bf5c04435d43511a9')
+    assert(hexlify(lc1.rk) == b'bb9020b8965f4df047e07f955f3c4b88418984aadc5cdb35096b9ea8fa5c3442')
+    lc2.handshake_act_three_responder(m)
+
+    assert(lc1.rk == lc2.sk)
+    assert(lc1.sk == lc2.rk)
+    assert(lc1.sn == lc2.rn)
+    assert(lc1.rn == lc2.sn)
+    assert(hexlify(lc2.rk) == b'969ab31b4d288cedf6218839b27a3e2140827047f2c0f01bf5c04435d43511a9')
+    assert(hexlify(lc2.sk) == b'bb9020b8965f4df047e07f955f3c4b88418984aadc5cdb35096b9ea8fa5c3442')
+    lc1.sck = lc1.chaining_key
+    lc2.sck = lc2.chaining_key
+    lc1.rck = lc1.chaining_key
+    lc2.rck = lc2.chaining_key
+
+    assert(lc1.chaining_key == lc2.chaining_key)
+    assert(hexlify(lc1.chaining_key) == b'919219dbb2920afa8db80f9a51787a840bcf111ed8d588caf9ab4be716e42b01')
+
+
+def test_shake():
+    rs_privkey = PrivateKey(unhexlify('2121212121212121212121212121212121212121212121212121212121212121'))
+    rs_pubkey = rs_privkey.public_key()
+    assert(hexlify(rs_pubkey.serializeCompressed()) == b'028d7500dd4c12685d1f568b4c2b5048e8534b873319f3a8daa612b469132ec7f7')
+
+    ls_privkey = PrivateKey(unhexlify('1111111111111111111111111111111111111111111111111111111111111111'))
+    ls_pubkey = ls_privkey.public_key()
+    assert(hexlify(ls_pubkey.serializeCompressed()) == b'034f355bdcb7cc0af728ef3cceb9615d90684bb5b2ca5f859ab0f0b704075871aa')
+
+    c1, c2 = socket.socketpair()
+
+    lc1 = LightningConnection(c1, rs_pubkey, ls_privkey, is_initiator=True)
+    lc2 = LightningConnection(c2, ls_pubkey, rs_privkey, is_initiator=False)
+
+    t = threading.Thread(target=lc2.shake)
+    t.start()
+    lc1.shake()
+    t.join()
+
+    assert(lc1.rk == lc2.sk)
+    assert(lc1.sk == lc2.rk)
+    assert(lc1.sn == lc2.rn)
+    assert(lc1.rn == lc2.sn)
+
+
+def test_read_key_rotation():
+    ls_privkey = PrivateKey(unhexlify('1111111111111111111111111111111111111111111111111111111111111111'))
+    rs_privkey = PrivateKey(unhexlify('2121212121212121212121212121212121212121212121212121212121212121'))
+    rs_pubkey = rs_privkey.public_key()
+    c1, c2 = socket.socketpair()
+    lc = LightningConnection(c1, rs_pubkey, ls_privkey, is_initiator=True)
+    # ck=0x919219dbb2920afa8db80f9a51787a840bcf111ed8d588caf9ab4be716e42b01
+    # sk=0x969ab31b4d288cedf6218839b27a3e2140827047f2c0f01bf5c04435d43511a9
+    # rk=0xbb9020b8965f4df047e07f955f3c4b88418984aadc5cdb35096b9ea8fa5c3442
+    lc.chaining_key = unhexlify(b'919219dbb2920afa8db80f9a51787a840bcf111ed8d588caf9ab4be716e42b01')
+    lc.sk = unhexlify(b'969ab31b4d288cedf6218839b27a3e2140827047f2c0f01bf5c04435d43511a9')
+    lc.rk = unhexlify(b'bb9020b8965f4df047e07f955f3c4b88418984aadc5cdb35096b9ea8fa5c3442')
+    lc.sn, lc.rn = 0, 0
+    lc.sck, lc.rck = lc.chaining_key, lc.chaining_key
+
+    msg = unhexlify(b'68656c6c6f')
+    lc.send_message(msg)
+    m = c2.recv(18 + 21)
+    assert(hexlify(m) == b'cf2b30ddf0cf3f80e7c35a6e6730b59fe802473180f396d88a8fb0db8cbcf25d2f214cf9ea1d95')
+
+    # Send 498 more messages, to get just below the switch threshold
+    for i in range(0, 498):
+        lc.send_message(msg)
+        m = c2.recv(18 + 21)
+    # Check the last send key against the test vector
+    assert(hexlify(lc.sk) == b'969ab31b4d288cedf6218839b27a3e2140827047f2c0f01bf5c04435d43511a9')
+
+    # This next message triggers the rotation:
+    lc.send_message(msg)
+    m = c2.recv(18 + 21)
+
+    # Now try to send with the new keys:
+    lc.send_message(msg)
+    m = c2.recv(18 + 21)
+    assert(hexlify(m) == b'178cb9d7387190fa34db9c2d50027d21793c9bc2d40b1e14dcf30ebeeeb220f48364f7a4c68bf8')
+
+    lc.send_message(msg)
+    m = c2.recv(18 + 21)
+    assert(hexlify(m) == b'1b186c57d44eb6de4c057c49940d79bb838a145cb528d6e8fd26dbe50a60ca2c104b56b60e45bd')
+
+    for i in range(0, 498):
+        lc.send_message(msg)
+        m = c2.recv(18 + 21)
+
+    lc.send_message(msg)
+    m = c2.recv(18 + 21)
+    assert(hexlify(m) == b'4a2f3cc3b5e78ddb83dcb426d9863d9d9a723b0337c89dd0b005d89f8d3c05c52b76b29b740f09')
+
+    lc.send_message(msg)
+    m = c2.recv(18 + 21)
+    assert(hexlify(m) == b'2ecd8c8a5629d0d02ab457a0fdd0f7b90a192cd46be5ecb6ca570bfc5e268338b1a16cf4ef2d36')
+
+
+def test_listen_connect():
+    """Roundtrip test using the public constructors.
+    """
+    n1_privkey = PrivateKey(unhexlify(b'1111111111111111111111111111111111111111111111111111111111111111'))
+    n2_privkey = PrivateKey(unhexlify('2121212121212121212121212121212121212121212121212121212121212121'))
+
+    lss = wire.LightningServerSocket(n2_privkey)
+    lss.bind(('0.0.0.0', 1234))
+    lss.listen()
+    port = lss.getsockname()[1]
+    print(port)
+
+    def connect():
+        lc = wire.connect(n1_privkey, n2_privkey.public_key(), '127.0.0.1', port)
+        lc.send_message(b'hello')
+        m = lc.read_message()
+        assert(m == b'world')
+
+    t = threading.Thread(target=connect)
+    t.daemon = True
+    t.start()
+
+    c, _ = lss.accept()
+    m = c.read_message()
+    assert(m == b'hello')
+    c.send_message(b'world')
+
+    t.join()