summaryrefslogtreecommitdiff
path: root/tests/util.py
blob: cdc835c95c7c330574474b0feec07a8cdaec7e3d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
from os.path import dirname, realpath, join
import os
import sys
import unittest

import pytest

from paramiko.py3compat import builtins
from paramiko.ssh_gss import GSS_AUTH_AVAILABLE


def _support(filename):
    return join(dirname(realpath(__file__)), filename)


needs_gssapi = pytest.mark.skipif(
    not GSS_AUTH_AVAILABLE, reason="No GSSAPI to test"
)


def needs_builtin(name):
    """
    Skip decorated test if builtin name does not exist.
    """
    reason = "Test requires a builtin '{}'".format(name)
    return pytest.mark.skipif(not hasattr(builtins, name), reason=reason)


slow = pytest.mark.slow

# GSSAPI / Kerberos related tests need a working Kerberos environment.
# The class `KerberosTestCase` provides such an environment or skips all tests.
# There are 3 distinct cases:
#
# - A Kerberos environment has already been created and the environment
#   contains the required information.
#
# - We can use the package 'k5test' to setup an working kerberos environment on
#   the fly.
#
# - We skip all tests.
#
# ToDo: add a Windows specific implementation?

if (
    os.environ.get("K5TEST_USER_PRINC", None)
    and os.environ.get("K5TEST_HOSTNAME", None)
    and os.environ.get("KRB5_KTNAME", None)
):  # add other vars as needed

    # The environment provides the required information
    class DummyK5Realm(object):
        def __init__(self):
            for k in os.environ:
                if not k.startswith("K5TEST_"):
                    continue
                setattr(self, k[7:].lower(), os.environ[k])
            self.env = {}

    class KerberosTestCase(unittest.TestCase):
        @classmethod
        def setUpClass(cls):
            cls.realm = DummyK5Realm()

        @classmethod
        def tearDownClass(cls):
            del cls.realm


else:
    try:
        # Try to setup a kerberos environment
        from k5test import KerberosTestCase
    except Exception:
        # Use a dummy, that skips all tests
        class KerberosTestCase(unittest.TestCase):
            @classmethod
            def setUpClass(cls):
                raise unittest.SkipTest(
                    "Missing extension package k5test. "
                    'Please run "pip install k5test" '
                    "to install it."
                )


def update_env(testcase, mapping, env=os.environ):
    """Modify os.environ during a test case and restore during cleanup."""
    saved_env = env.copy()

    def replace(target, source):
        target.update(source)
        for k in list(target):
            if k not in source:
                target.pop(k, None)

    testcase.addCleanup(replace, env, saved_env)
    env.update(mapping)
    return testcase


def k5shell(args=None):
    """Create a shell with an kerberos environment

    This can be used to debug paramiko or to test the old GSSAPI.
    To test a different GSSAPI, simply activate a suitable venv
    within the shell.
    """
    import k5test
    import atexit
    import subprocess

    k5 = k5test.K5Realm()
    atexit.register(k5.stop)
    os.environ.update(k5.env)
    for n in ("realm", "user_princ", "hostname"):
        os.environ["K5TEST_" + n.upper()] = getattr(k5, n)

    if not args:
        args = sys.argv[1:]
    if not args:
        args = [os.environ.get("SHELL", "bash")]
    sys.exit(subprocess.call(args))