Merge pull request #159 from libp2p/security-dev

Implement security

libp2p/__init__.py

@@ -2,6 +2,7 @@ import asyncio
 import multiaddr
 
 from Crypto.PublicKey import RSA
+from libp2p.security.insecure_security import InsecureTransport
 from .peer.peerstore import PeerStore
 from .peer.id import id_from_public_key
 from .network.swarm import Swarm
@@ -75,7 +76,7 @@ def initialize_default_swarm(
     # TODO TransportUpgrader is not doing anything really
     # TODO parse muxer and sec to pass into TransportUpgrader
     muxer = muxer_opt or ["mplex/6.7.0"]
-    sec = sec_opt or ["secio"]
+    sec = sec_opt or {"insecure/1.0.0": InsecureTransport("insecure")}
     upgrader = TransportUpgrader(sec, muxer)
 
     peerstore = peerstore_opt or PeerStore()

libp2p/network/connection/raw_connection.py

@@ -1,6 +1,5 @@
 from .raw_connection_interface import IRawConnection
 
-
 class RawConnection(IRawConnection):
 
     def __init__(self, ip, port, reader, writer, initiator):
@@ -12,6 +11,19 @@ class RawConnection(IRawConnection):
         self._next_id = 0 if initiator else 1
         self.initiator = initiator
 
+    async def write(self, data):
+        self.writer.write(data)
+        self.writer.write("\n".encode())
+        await self.writer.drain()
+
+    async def read(self):
+        line = await self.reader.readline()
+        adjusted_line = line.decode().rstrip('\n')
+
+        # TODO: figure out a way to remove \n without going back and forth with
+        # encoding and decoding
+        return adjusted_line.encode()
+
     def close(self):
         self.writer.close()
 

libp2p/network/swarm.py

@@ -72,8 +72,10 @@ class Swarm(INetwork):
             # Transport dials peer (gets back a raw conn)
             raw_conn = await self.transport.dial(multiaddr, self.self_id)
 
-            # Use upgrader to upgrade raw conn to muxed conn
-            muxed_conn = self.upgrader.upgrade_connection(raw_conn, \
+            # Per, https://discuss.libp2p.io/t/multistream-security/130, we first secure
+            # the conn and then mux the conn
+            secured_conn = await self.upgrader.upgrade_security(raw_conn, peer_id, True)
+            muxed_conn = self.upgrader.upgrade_connection(secured_conn, \
                 self.generic_protocol_handler, peer_id)
 
             # Store muxed connection in connections
@@ -148,7 +150,11 @@ class Swarm(INetwork):
                 # to appropriate stream handler (using multiaddr)
                 raw_conn = RawConnection(multiaddr.value_for_protocol('ip4'),
                                          multiaddr.value_for_protocol('tcp'), reader, writer, False)
-                muxed_conn = self.upgrader.upgrade_connection(raw_conn, \
+
+                # Per, https://discuss.libp2p.io/t/multistream-security/130, we first secure
+                # the conn and then mux the conn
+                secured_conn = await self.upgrader.upgrade_security(raw_conn, peer_id, False)
+                muxed_conn = self.upgrader.upgrade_connection(secured_conn, \
                     self.generic_protocol_handler, peer_id)
 
                 # Store muxed_conn with peer id

libp2p/protocol_muxer/multiselect_client.py

@@ -45,7 +45,6 @@ class MultiselectClient(IMultiselectClient):
         :param stream: stream to communicate with multiselect over
         :return: selected protocol
         """
-
         # Create a communicator to handle all communication across the stream
         communicator = MultiselectCommunicator(stream)
 

libp2p/protocol_muxer/multiselect_communicator.py

@@ -8,19 +8,24 @@ class MultiselectCommunicator(IMultiselectCommunicator):
     which is necessary for them to work
     """
 
-    def __init__(self, stream):
-        self.stream = stream
+    def __init__(self, reader_writer):
+        """
+        MultistreamCommunicator expects a reader_writer object that has
+        an async read and an async write function (this could be a stream,
+        raw connection, or other object implementing those functions)
+        """
+        self.reader_writer = reader_writer
 
     async def write(self, msg_str):
         """
-        Write message to stream
+        Write message to reader_writer
         :param msg_str: message to write
         """
-        await self.stream.write(msg_str.encode())
+        await self.reader_writer.write(msg_str.encode())
 
     async def read_stream_until_eof(self):
         """
-        Reads message from stream until EOF
+        Reads message from reader_writer until EOF
         """
-        read_str = (await self.stream.read()).decode()
+        read_str = (await self.reader_writer.read()).decode()
         return read_str

libp2p/security/insecure_security.py

@@ -0,0 +1,44 @@
+from libp2p.security.secure_transport_interface import ISecureTransport
+from libp2p.security.secure_conn_interface import ISecureConn
+
+class InsecureTransport(ISecureTransport):
+
+    def __init__(self, transport_id):
+        self.transport_id = transport_id
+
+    async def secure_inbound(self, conn):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are not the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """
+        insecure_conn = InsecureConn(conn, self.transport_id)
+        return insecure_conn
+
+    async def secure_outbound(self, conn, peer_id):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """
+        insecure_conn = InsecureConn(conn, self.transport_id)
+        return insecure_conn
+
+class InsecureConn(ISecureConn):
+
+    def __init__(self, conn, conn_id):
+        self.conn = conn
+        self.details = {}
+        self.details["id"] = conn_id
+
+    def get_conn(self):
+        """
+        :return: connection object that has been made secure
+        """
+        return self.conn
+
+    def get_security_details(self):
+        """
+        :return: map containing details about the connections security
+        """
+        return self.details

libp2p/security/secure_conn_interface.py

@@ -0,0 +1,23 @@
+from abc import ABC, abstractmethod
+
+# pylint: disable=W0105
+
+"""
+Represents a secured connection object, which includes a connection and details about the security
+involved in the secured connection
+
+Relevant go repo: https://github.com/libp2p/go-conn-security/blob/master/interface.go
+"""
+class ISecureConn(ABC):
+
+    @abstractmethod
+    def get_conn(self):
+        """
+        :return: connection object that has been made secure
+        """
+
+    @abstractmethod
+    def get_security_details(self):
+        """
+        :return: map containing details about the connections security
+        """

libp2p/security/secure_transport_interface.py

@@ -0,0 +1,27 @@
+from abc import ABC, abstractmethod
+
+# pylint: disable=W0105
+
+"""
+Transport that is used to secure a connection. This transport is
+chosen by a security transport multistream module.
+
+Relevant go repo: https://github.com/libp2p/go-conn-security/blob/master/interface.go
+"""
+class ISecureTransport(ABC):
+
+    @abstractmethod
+    async def secure_inbound(self, conn):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are not the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """
+
+    @abstractmethod
+    async def secure_outbound(self, conn, peer_id):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """

libp2p/security/security_multistream.py

@@ -0,0 +1,88 @@
+from abc import ABC
+from libp2p.protocol_muxer.multiselect_client import MultiselectClient
+from libp2p.protocol_muxer.multiselect import Multiselect
+
+# pylint: disable=W0105
+
+"""
+Represents a secured connection object, which includes a connection and details about the security
+involved in the secured connection
+
+Relevant go repo: https://github.com/libp2p/go-conn-security/blob/master/interface.go
+"""
+class SecurityMultistream(ABC):
+
+    def __init__(self):
+        # Map protocol to secure transport
+        self.transports = {}
+
+        # Create multiselect
+        self.multiselect = Multiselect()
+
+        # Create multiselect client
+        self.multiselect_client = MultiselectClient()
+
+    def add_transport(self, protocol, transport):
+        # Associate protocol with transport
+        self.transports[protocol] = transport
+
+        # Add protocol and handler to multiselect
+        # Note: None is added as the handler for the given protocol since
+        # we only care about selecting the protocol, not any handler function
+        self.multiselect.add_handler(protocol, None)
+
+
+    async def secure_inbound(self, conn):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are not the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """
+
+        # Select a secure transport
+        transport = await self.select_transport(conn, False)
+
+        # Create secured connection
+        secure_conn = await transport.secure_inbound(conn)
+
+        return secure_conn
+
+
+    async def secure_outbound(self, conn, peer_id):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """
+
+        # Select a secure transport
+        transport = await self.select_transport(conn, True)
+
+        # Create secured connection
+        secure_conn = await transport.secure_outbound(conn, peer_id)
+
+        return secure_conn
+
+
+    async def select_transport(self, conn, initiator):
+        """
+        Select a transport that both us and the node on the
+        other end of conn support and agree on
+        :param conn: conn to choose a transport over
+        :param initiator: true if we are the initiator, false otherwise
+        :return: selected secure transport
+        """
+        # TODO: Is conn acceptable to multiselect/multiselect_client
+        # instead of stream? In go repo, they pass in a raw conn
+        # (https://raw.githubusercontent.com/libp2p/go-conn-security-multistream/master/ssms.go)
+
+        protocol = None
+        if initiator:
+            # Select protocol if initiator
+            protocol = \
+                await self.multiselect_client.select_one_of(list(self.transports.keys()), conn)
+        else:
+            # Select protocol if non-initiator
+            protocol, _ = await self.multiselect.negotiate(conn)
+        # Return transport from protocol
+        return self.transports[protocol]

libp2p/security/simple_security.py

@@ -0,0 +1,61 @@
+import asyncio
+from libp2p.security.secure_transport_interface import ISecureTransport
+from libp2p.security.secure_conn_interface import ISecureConn
+
+class SimpleSecurityTransport(ISecureTransport):
+
+    def __init__(self, key_phrase):
+        self.key_phrase = key_phrase
+
+    async def secure_inbound(self, conn):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are not the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """
+        await conn.write(self.key_phrase.encode())
+        incoming = (await conn.read()).decode()
+
+        if incoming != self.key_phrase:
+            raise Exception("Key phrase differed between nodes. Expected " + self.key_phrase)
+
+        secure_conn = SimpleSecureConn(conn, self.key_phrase)
+        return secure_conn
+
+    async def secure_outbound(self, conn, peer_id):
+        """
+        Secure the connection, either locally or by communicating with opposing node via conn,
+        for an inbound connection (i.e. we are the initiator)
+        :return: secure connection object (that implements secure_conn_interface)
+        """
+        await conn.write(self.key_phrase.encode())
+        incoming = (await conn.read()).decode()
+
+        # Force context switch, as this security transport is built for testing locally
+        # in a single event loop
+        await asyncio.sleep(0)
+
+        if incoming != self.key_phrase:
+            raise Exception("Key phrase differed between nodes. Expected " + self.key_phrase)
+
+        secure_conn = SimpleSecureConn(conn, self.key_phrase)
+        return secure_conn
+
+class SimpleSecureConn(ISecureConn):
+
+    def __init__(self, conn, key_phrase):
+        self.conn = conn
+        self.details = {}
+        self.details["key_phrase"] = key_phrase
+
+    def get_conn(self):
+        """
+        :return: connection object that has been made secure
+        """
+        return self.conn
+
+    def get_security_details(self):
+        """
+        :return: map containing details about the connections security
+        """
+        return self.details

libp2p/stream_muxer/mplex/mplex.py

@@ -11,7 +11,7 @@ class Mplex(IMuxedConn):
     reference: https://github.com/libp2p/go-mplex/blob/master/multiplex.go
     """
 
-    def __init__(self, conn, generic_protocol_handler, peer_id):
+    def __init__(self, secured_conn, generic_protocol_handler, peer_id):
         """
         create a new muxed connection
         :param conn: an instance of raw connection
@@ -19,10 +19,11 @@ class Mplex(IMuxedConn):
         for new muxed streams
         :param peer_id: peer_id of peer the connection is to
         """
-        super(Mplex, self).__init__(conn, generic_protocol_handler, peer_id)
+        super(Mplex, self).__init__(secured_conn, generic_protocol_handler, peer_id)
 
-        self.raw_conn = conn
-        self.initiator = conn.initiator
+        self.secured_conn = secured_conn
+        self.raw_conn = secured_conn.get_conn()
+        self.initiator = self.raw_conn.initiator
 
         # Store generic protocol handler
         self.generic_protocol_handler = generic_protocol_handler

libp2p/stream_muxer/muxed_connection_interface.py

@@ -10,7 +10,7 @@ class IMuxedConn(ABC):
     def __init__(self, conn, generic_protocol_handler, peer_id):
         """
         create a new muxed connection
-        :param conn: an instance of raw connection
+        :param conn: an instance of secured connection
         :param generic_protocol_handler: generic protocol handler
         for new muxed streams
         :param peer_id: peer_id of peer the connection is to

libp2p/transport/tcp/tcp.py

@@ -82,9 +82,10 @@ class TCP(ITransport):
         await writer.drain()
 
         # Await ack for peer id
-        ack = (await reader.read(1024)).decode()
+        expected_ack_str = "received peer id"
+        ack = (await reader.read(len(expected_ack_str))).decode()
 
-        if ack != "received peer id":
+        if ack != expected_ack_str:
             raise Exception("Receiver did not receive peer id")
 
         return RawConnection(host, port, reader, writer, True)

libp2p/transport/upgrader.py

@@ -1,25 +1,36 @@
 from libp2p.stream_muxer.mplex.mplex import Mplex
+from libp2p.security.security_multistream import SecurityMultistream
 
 
 class TransportUpgrader:
     # pylint: disable=no-self-use
 
     def __init__(self, secOpt, muxerOpt):
-        self.sec = secOpt
+        # Store security option
+        self.security_multistream = SecurityMultistream()
+        for key in secOpt:
+            self.security_multistream.add_transport(key, secOpt[key])
+
+        # Store muxer option
         self.muxer = muxerOpt
 
     def upgrade_listener(self, transport, listeners):
         """
-        upgrade multiaddr listeners to libp2p-transport listeners
-
+        Upgrade multiaddr listeners to libp2p-transport listeners
         """
 
-    def upgrade_security(self):
-        pass
+    async def upgrade_security(self, raw_conn, peer_id, initiator):
+        """
+        Upgrade conn to be a secured connection
+        """
+        if initiator:
+            return await self.security_multistream.secure_outbound(raw_conn, peer_id)
+
+        return await self.security_multistream.secure_inbound(raw_conn)
 
     def upgrade_connection(self, conn, generic_protocol_handler, peer_id):
         """
-        upgrade raw connection to muxed connection
+        Upgrade raw connection to muxed connection
         """
 
         # For PoC, no security, default to mplex

tests/security/test_security_multistream.py

@@ -0,0 +1,159 @@
+import asyncio
+import multiaddr
+import pytest
+
+from libp2p import new_node
+from libp2p.peer.peerinfo import info_from_p2p_addr
+from libp2p.protocol_muxer.multiselect_client import MultiselectClientError
+from libp2p.security.insecure_security import InsecureTransport
+from libp2p.security.simple_security import SimpleSecurityTransport
+from tests.utils import cleanup
+
+# TODO: Add tests for multiple streams being opened on different
+# protocols through the same connection
+
+def peer_id_for_node(node):
+    addr = node.get_addrs()[0]
+    info = info_from_p2p_addr(addr)
+    return info.peer_id
+
+async def connect(node1, node2):
+    """
+    Connect node1 to node2
+    """
+    addr = node2.get_addrs()[0]
+    info = info_from_p2p_addr(addr)
+    await node1.connect(info)
+
+async def perform_simple_test(assertion_func, \
+        transports_for_initiator, transports_for_noninitiator):
+
+    # Create libp2p nodes and connect them, then secure the connection, then check
+    # the proper security was chosen
+    # TODO: implement -- note we need to introduce the notion of communicating over a raw connection
+    # for testing, we do NOT want to communicate over a stream so we can't just create two nodes
+    # and use their conn because our mplex will internally relay messages to a stream
+    sec_opt1 = transports_for_initiator
+    sec_opt2 = transports_for_noninitiator
+
+    node1 = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/0"], sec_opt=sec_opt1)
+    node2 = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/0"], sec_opt=sec_opt2)
+
+    await node1.get_network().listen(multiaddr.Multiaddr("/ip4/127.0.0.1/tcp/0"))
+    await node2.get_network().listen(multiaddr.Multiaddr("/ip4/127.0.0.1/tcp/0"))
+
+    await connect(node1, node2)
+
+    # Wait a very short period to allow conns to be stored (since the functions
+    # storing the conns are async, they may happen at slightly different times
+    # on each node)
+    await asyncio.sleep(0.1)
+
+    # Get conns
+    node1_conn = node1.get_network().connections[peer_id_for_node(node2)]
+    node2_conn = node2.get_network().connections[peer_id_for_node(node1)]
+
+    # Perform assertion
+    assertion_func(node1_conn.secured_conn.get_security_details())
+    assertion_func(node2_conn.secured_conn.get_security_details())
+
+    # Success, terminate pending tasks.
+    await cleanup()
+
+
+@pytest.mark.asyncio
+async def test_single_insecure_security_transport_succeeds():
+    transports_for_initiator = {"foo": InsecureTransport("foo")}
+    transports_for_noninitiator = {"foo": InsecureTransport("foo")}
+
+    def assertion_func(details):
+        assert details["id"] == "foo"
+
+    await perform_simple_test(assertion_func,
+                              transports_for_initiator, transports_for_noninitiator)
+
+@pytest.mark.asyncio
+async def test_single_simple_test_security_transport_succeeds():
+    transports_for_initiator = {"tacos": SimpleSecurityTransport("tacos")}
+    transports_for_noninitiator = {"tacos": SimpleSecurityTransport("tacos")}
+
+    def assertion_func(details):
+        assert details["key_phrase"] == "tacos"
+
+    await perform_simple_test(assertion_func,
+                              transports_for_initiator, transports_for_noninitiator)
+
+@pytest.mark.asyncio
+async def test_two_simple_test_security_transport_for_initiator_succeeds():
+    transports_for_initiator = {"tacos": SimpleSecurityTransport("tacos"),
+                                "shleep": SimpleSecurityTransport("shleep")}
+    transports_for_noninitiator = {"shleep": SimpleSecurityTransport("shleep")}
+
+    def assertion_func(details):
+        assert details["key_phrase"] == "shleep"
+
+    await perform_simple_test(assertion_func,
+                              transports_for_initiator, transports_for_noninitiator)
+
+@pytest.mark.asyncio
+async def test_two_simple_test_security_transport_for_noninitiator_succeeds():
+    transports_for_initiator = {"tacos": SimpleSecurityTransport("tacos")}
+    transports_for_noninitiator = {"shleep": SimpleSecurityTransport("shleep"),
+                                   "tacos": SimpleSecurityTransport("tacos")}
+
+    def assertion_func(details):
+        assert details["key_phrase"] == "tacos"
+
+    await perform_simple_test(assertion_func,
+                              transports_for_initiator, transports_for_noninitiator)
+
+
+@pytest.mark.asyncio
+async def test_two_simple_test_security_transport_for_both_succeeds():
+    transports_for_initiator = {"a": SimpleSecurityTransport("a"),
+                                "b": SimpleSecurityTransport("b")}
+    transports_for_noninitiator = {"c": SimpleSecurityTransport("c"),
+                                   "b": SimpleSecurityTransport("b")}
+
+    def assertion_func(details):
+        assert details["key_phrase"] == "b"
+
+    await perform_simple_test(assertion_func,
+                              transports_for_initiator, transports_for_noninitiator)
+
+@pytest.mark.asyncio
+async def test_multiple_security_none_the_same_fails():
+    transports_for_initiator = {"a": SimpleSecurityTransport("a"),
+                                "b": SimpleSecurityTransport("b")}
+    transports_for_noninitiator = {"c": SimpleSecurityTransport("c"),
+                                   "d": SimpleSecurityTransport("d")}
+
+    def assertion_func(_):
+        assert False
+
+    with pytest.raises(MultiselectClientError):
+        await perform_simple_test(assertion_func,
+                                  transports_for_initiator, transports_for_noninitiator)
+
+    await cleanup()
+
+@pytest.mark.asyncio
+async def test_default_insecure_security():
+    transports_for_initiator = None
+    transports_for_noninitiator = None
+
+    details1 = None
+    details2 = None
+
+    def assertion_func(details):
+        nonlocal details1
+        nonlocal details2
+        if not details1:
+            details1 = details
+        elif not details2:
+            details2 = details
+        else:
+            assert details1 == details2
+
+    await perform_simple_test(assertion_func,
+                              transports_for_initiator, transports_for_noninitiator)