# Copyright (C) 2008  Robey Pointer <robeypointer@gmail.com>
#
# This file is part of paramiko.
#
# Paramiko is free software; you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation; either version 2.1 of the License, or (at your option)
# any later version.
#
# Paramiko is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with Paramiko; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA.

"""
Some unit tests for authenticating over a Transport.
"""

import sys
import threading
import unittest
from time import sleep

from paramiko import (
    Transport,
    ServerInterface,
    RSAKey,
    DSSKey,
    BadAuthenticationType,
    InteractiveQuery,
    AuthenticationException,
)
from paramiko import AUTH_FAILED, AUTH_PARTIALLY_SUCCESSFUL, AUTH_SUCCESSFUL
from paramiko.util import u

from ._loop import LoopSocket
from ._util import _support, slow


_pwd = u("\u2022")


class NullServer(ServerInterface):
    paranoid_did_password = False
    paranoid_did_public_key = False
    paranoid_key = DSSKey.from_private_key_file(_support("dss.key"))

    def get_allowed_auths(self, username):
        if username == "slowdive":
            return "publickey,password"
        if username == "paranoid":
            if (
                not self.paranoid_did_password
                and not self.paranoid_did_public_key
            ):
                return "publickey,password"
            elif self.paranoid_did_password:
                return "publickey"
            else:
                return "password"
        if username == "commie":
            return "keyboard-interactive"
        if username == "utf8":
            return "password"
        if username == "non-utf8":
            return "password"
        return "publickey"

    def check_auth_password(self, username, password):
        if (username == "slowdive") and (password == "pygmalion"):
            return AUTH_SUCCESSFUL
        if (username == "paranoid") and (password == "paranoid"):
            # 2-part auth (even openssh doesn't support this)
            self.paranoid_did_password = True
            if self.paranoid_did_public_key:
                return AUTH_SUCCESSFUL
            return AUTH_PARTIALLY_SUCCESSFUL
        if (username == "utf8") and (password == _pwd):
            return AUTH_SUCCESSFUL
        if (username == "non-utf8") and (password == "\xff"):
            return AUTH_SUCCESSFUL
        if username == "bad-server":
            raise Exception("Ack!")
        if username == "unresponsive-server":
            sleep(5)
            return AUTH_SUCCESSFUL
        return AUTH_FAILED

    def check_auth_publickey(self, username, key):
        if (username == "paranoid") and (key == self.paranoid_key):
            # 2-part auth
            self.paranoid_did_public_key = True
            if self.paranoid_did_password:
                return AUTH_SUCCESSFUL
            return AUTH_PARTIALLY_SUCCESSFUL
        return AUTH_FAILED

    def check_auth_interactive(self, username, submethods):
        if username == "commie":
            self.username = username
            return InteractiveQuery(
                "password", "Please enter a password.", ("Password", False)
            )
        return AUTH_FAILED

    def check_auth_interactive_response(self, responses):
        if self.username == "commie":
            if (len(responses) == 1) and (responses[0] == "cat"):
                return AUTH_SUCCESSFUL
        return AUTH_FAILED


class AuthTest(unittest.TestCase):
    def setUp(self):
        self.socks = LoopSocket()
        self.sockc = LoopSocket()
        self.sockc.link(self.socks)
        self.tc = Transport(self.sockc)
        self.ts = Transport(self.socks)

    def tearDown(self):
        self.tc.close()
        self.ts.close()
        self.socks.close()
        self.sockc.close()

    def start_server(self):
        host_key = RSAKey.from_private_key_file(_support("rsa.key"))
        self.public_host_key = RSAKey(data=host_key.asbytes())
        self.ts.add_server_key(host_key)
        self.event = threading.Event()
        self.server = NullServer()
        self.assertTrue(not self.event.is_set())
        self.ts.start_server(self.event, self.server)

    def verify_finished(self):
        self.event.wait(1.0)
        self.assertTrue(self.event.is_set())
        self.assertTrue(self.ts.is_active())

    def test_bad_auth_type(self):
        """
        verify that we get the right exception when an unsupported auth
        type is requested.
        """
        self.start_server()
        try:
            self.tc.connect(
                hostkey=self.public_host_key,
                username="unknown",
                password="error",
            )
            self.assertTrue(False)
        except:
            etype, evalue, etb = sys.exc_info()
            self.assertEqual(BadAuthenticationType, etype)
            self.assertEqual(["publickey"], evalue.allowed_types)

    def test_bad_password(self):
        """
        verify that a bad password gets the right exception, and that a retry
        with the right password works.
        """
        self.start_server()
        self.tc.connect(hostkey=self.public_host_key)
        try:
            self.tc.auth_password(username="slowdive", password="error")
            self.assertTrue(False)
        except:
            etype, evalue, etb = sys.exc_info()
            self.assertTrue(issubclass(etype, AuthenticationException))
        self.tc.auth_password(username="slowdive", password="pygmalion")
        self.verify_finished()

    def test_multipart_auth(self):
        """
        verify that multipart auth works.
        """
        self.start_server()
        self.tc.connect(hostkey=self.public_host_key)
        remain = self.tc.auth_password(
            username="paranoid", password="paranoid"
        )
        self.assertEqual(["publickey"], remain)
        key = DSSKey.from_private_key_file(_support("dss.key"))
        remain = self.tc.auth_publickey(username="paranoid", key=key)
        self.assertEqual([], remain)
        self.verify_finished()

    def test_interactive_auth(self):
        """
        verify keyboard-interactive auth works.
        """
        self.start_server()
        self.tc.connect(hostkey=self.public_host_key)

        def handler(title, instructions, prompts):
            self.got_title = title
            self.got_instructions = instructions
            self.got_prompts = prompts
            return ["cat"]

        remain = self.tc.auth_interactive("commie", handler)
        self.assertEqual(self.got_title, "password")
        self.assertEqual(self.got_prompts, [("Password", False)])
        self.assertEqual([], remain)
        self.verify_finished()

    def test_interactive_auth_fallback(self):
        """
        verify that a password auth attempt will fallback to "interactive"
        if password auth isn't supported but interactive is.
        """
        self.start_server()
        self.tc.connect(hostkey=self.public_host_key)
        remain = self.tc.auth_password("commie", "cat")
        self.assertEqual([], remain)
        self.verify_finished()

    def test_auth_utf8(self):
        """
        verify that utf-8 encoding happens in authentication.
        """
        self.start_server()
        self.tc.connect(hostkey=self.public_host_key)
        remain = self.tc.auth_password("utf8", _pwd)
        self.assertEqual([], remain)
        self.verify_finished()

    def test_auth_non_utf8(self):
        """
        verify that non-utf-8 encoded passwords can be used for broken
        servers.
        """
        self.start_server()
        self.tc.connect(hostkey=self.public_host_key)
        remain = self.tc.auth_password("non-utf8", "\xff")
        self.assertEqual([], remain)
        self.verify_finished()

    def test_auth_gets_disconnected(self):
        """
        verify that we catch a server disconnecting during auth, and report
        it as an auth failure.
        """
        self.start_server()
        self.tc.connect(hostkey=self.public_host_key)
        try:
            self.tc.auth_password("bad-server", "hello")
        except:
            etype, evalue, etb = sys.exc_info()
            self.assertTrue(issubclass(etype, AuthenticationException))

    @slow
    def test_auth_non_responsive(self):
        """
        verify that authentication times out if server takes to long to
        respond (or never responds).
        """
        self.tc.auth_timeout = 1  # 1 second, to speed up test
        self.start_server()
        self.tc.connect()
        try:
            self.tc.auth_password("unresponsive-server", "hello")
        except:
            etype, evalue, etb = sys.exc_info()
            self.assertTrue(issubclass(etype, AuthenticationException))
            self.assertTrue("Authentication timeout" in str(evalue))