Fix RuntimeError for the JSON export (#44)

* Fix RuntimeError for the JSON export

It is never a good idea to modify an iterable while iterating over it.

Copying the iterable fixes #41

modified:   ssh-audit.py

* Add test case for #41

new file:   test/test_build_struct.py

* Fix linting error

modified:   test/test_build_struct.py
This commit is contained in:
Jürgen Gmach 2020-07-03 20:56:46 +02:00 committed by GitHub
parent 282770e698
commit bf1fbbfa43
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2 changed files with 42 additions and 1 deletions

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@ -3366,7 +3366,7 @@ def build_struct(banner: Optional['SSH.Banner'], kex: Optional['SSH2.Kex'] = Non
host_keys = kex.host_keys()
# Normalize all RSA key types to 'ssh-rsa'. Otherwise, due to Python's order-indifference dictionary types, we would iterate key types in unpredictable orders, which interferes with the docker testing framework (i.e.: tests would fail because elements are reported out of order, even though the output is semantically the same).
for host_key_type in host_keys.keys():
for host_key_type in list(host_keys.keys())[:]:
if host_key_type in SSH2.HostKeyTest.RSA_FAMILY:
val = host_keys[host_key_type]
del host_keys[host_key_type]

41
test/test_build_struct.py Normal file
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@ -0,0 +1,41 @@
import os
import pytest
@pytest.fixture
def kex(ssh_audit):
kex_algs, key_algs = [], []
enc, mac, compression, languages = [], [], ['none'], []
cli = ssh_audit.SSH2.KexParty(enc, mac, compression, languages)
enc, mac, compression, languages = [], [], ['none'], []
srv = ssh_audit.SSH2.KexParty(enc, mac, compression, languages)
cookie = os.urandom(16)
kex = ssh_audit.SSH2.Kex(cookie, kex_algs, key_algs, cli, srv, 0)
return kex
def test_prevent_runtime_error_regression(ssh_audit, kex):
"""Prevent a regression of https://github.com/jtesta/ssh-audit/issues/41
The following test setup does not contain any sensible data.
It was made up to reproduce a situation when there are several host
keys, and an error occurred when iterating and modifying them at the
same time.
"""
kex.set_host_key("ssh-rsa", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa1", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa2", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa3", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa4", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa5", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa6", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa7", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
kex.set_host_key("ssh-rsa8", b"\x00\x00\x00\x07ssh-rsa\x00\x00\x00")
rv = ssh_audit.build_struct(banner=None, kex=kex)
assert len(rv["fingerprints"]) == 9
for key in ['banner', 'compression', 'enc', 'fingerprints', 'kex', 'key', 'mac']:
assert key in rv