view test/test_mailgw_roundupmessage.py @ 5726:e199d0ae4a25

issue2551033: prevent reverse engineering hidden data by using etags as an oracle to identify when the right data has been guessed. Identified by Joseph Myers who also suggested remediation methods. Implemented John Rouillard.
author John Rouillard <rouilj@ieee.org>
date Thu, 23 May 2019 18:56:57 -0400
parents 081be318661b
children cacef71b3a54
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# -*- coding: utf-8 -*-
import email
import textwrap
from unittest import TestCase

from roundup.mailgw import RoundupMessage

PART_TYPES = {
    'multipart/signed': '    boundary="boundary-{indent}";\n',
    'multipart/mixed': '    boundary="boundary-{indent}";\n',
    'multipart/alternative': '    boundary="boundary-{indent}";\n',
    'text/plain': '    name="foo.txt"\n\nfoo\n',
    'text/plain_2': '    name="foo2.txt"\n\nfoo2\n',
    'text/plain_3': '    name="foo3.txt"\n\nfoo3\n',
    'text/html': '    name="foo.html"\n\n<html>foo</html>\n',
    'application/pgp-signature': '    name="foo.gpg"\nfoo\n',
    'application/pdf': '    name="foo.pdf"\nfoo\n',
    'application/pdf_2': '    name="foo2.pdf"\nfoo2\n',
    'message/rfc822': '\nSubject: foo\n\nfoo\n',
}


def message_from_string(msg):
    return email.message_from_string(
        textwrap.dedent(msg).lstrip(),
        RoundupMessage)


def construct_message(spec, depth=0):
    parts = []
    for content_type in spec:
        if isinstance(content_type, list):
            parts.extend(construct_message(content_type, depth=(depth + 1)))
            parts.append('\n--boundary-{0}--\n'.format(depth + 1))
        else:
            if depth > 0:
                parts.append('\n--boundary-{0}\n'.format(depth))

            parts.append(
                'Content-Type: {0};\n'.format(content_type.split('_')[0]))
            parts.append(PART_TYPES[content_type].format(indent=(depth + 1)))

    if depth == 0:
        return email.message_from_string(''.join(parts), RoundupMessage)
    else:
        return parts


class FlattenRoundupMessageTests(TestCase):
    def test_flatten_with_from(self):
        msg_string = textwrap.dedent("""
            From: Some User <some.user@example.com>
            To: issue_tracker@example.com
            Message-Id: <dummy_test_message_id>
            Subject: Test line start with from

            From here to there!
        """).lstrip()

        msg = email.message_from_string(msg_string, RoundupMessage)
        self.assertEqual(msg.flatten(), msg_string)


class HeaderRoundupMessageTests(TestCase):
    msg = message_from_string("""
        Content-Type: text/plain;
            charset="iso-8859-1"
        From: =?utf8?b?SOKCrGxsbw==?= <hello@example.com>
        To: Issue Tracker <issue_tracker@example.com>
        Cc: =?utf8?b?SOKCrGxsbw==?= <hello@example.com>,
            Some User <some.user@example.com>
        Message-Id: <dummy_test_message_id>
        Subject: [issue] Testing...

        This is a test submission of a new issue.
    """)

    def test_get_plain_header(self):
        self.assertEqual(
            self.msg.get_header('to'),
            'Issue Tracker <issue_tracker@example.com>')

    def test_get_encoded_header(self):
        self.assertEqual(
            self.msg.get_header('from'),
            'H€llo <hello@example.com>')

    def test_get_address_list(self):
        self.assertEqual(self.msg.get_address_list('cc'), [
            ('H€llo', 'hello@example.com'),
            ('Some User', 'some.user@example.com'),
        ])


class BodyRoundupMessageTests(TestCase):
    def test_get_body_iso_8859_1(self):
        msg = message_from_string("""
            Content-Type: text/plain; charset="iso-8859-1"
            Content-Transfer-Encoding: quoted-printable

            A message with encoding (encoded oe =F6)
        """)

        self.assertEqual(
            msg.get_body(),
            'A message with encoding (encoded oe ö)\n')

    def test_get_body_utf_8(self):
        msg = message_from_string("""
            Content-Type: text/plain; charset="utf-8"
            Content-Transfer-Encoding: quoted-printable

            A message with encoding (encoded oe =C3=B6)
        """)

        self.assertEqual(
            msg.get_body(),
            'A message with encoding (encoded oe ö)\n')

    def test_get_body_base64(self):
        msg = message_from_string("""
            Content-Type: application/octet-stream
            Content-Disposition: attachment; filename="message.dat"
            Content-Transfer-Encoding: base64

            dGVzdCBlbmNvZGVkIG1lc3NhZ2U=
        """)

        self.assertEqual(msg.get_body(), b'test encoded message')


class AsAttachmentRoundupMessageTests(TestCase):
    def test_text_plain(self):
        msg = message_from_string("""
            Content-Type: text/plain; charset="iso-8859-1

            Plain text message
        """)

        self.assertEqual(
            msg.as_attachment(),
            (None, 'text/plain', 'Plain text message\n'))

    def test_octet_stream(self):
        msg = message_from_string("""
            Content-Type: application/octet-stream
            Content-Disposition: attachment; filename="message.dat"
            Content-Transfer-Encoding: base64

            dGVzdCBlbmNvZGVkIG1lc3NhZ2U=
        """)

        self.assertEqual(
            msg.as_attachment(),
            ('message.dat', 'application/octet-stream',
             b'test encoded message'))

    def test_rfc822(self):
        msg = message_from_string("""
            Content-Type: message/rfc822

            Subject: foo

            foo
        """)

        self.assertEqual(
            msg.as_attachment(),
            ('foo.eml', 'message/rfc822', 'Subject: foo\n\nfoo\n'))

    def test_rfc822_no_subject(self):
        msg = message_from_string("""
            Content-Type: message/rfc822

            X-No-Headers: nope

            foo
        """)

        self.assertEqual(
            msg.as_attachment(),
            (None, 'message/rfc822', 'X-No-Headers: nope\n\nfoo\n'))

    def test_rfc822_no_payload(self):
        msg = message_from_string("""\
            Content-Type: message/rfc822
        """)

        self.assertEqual(
            msg.as_attachment(),
            (None, 'message/rfc822', '\n'))


class ExtractContentRoundupMessageTests(TestCase):
    def test_text_plain(self):
        msg = construct_message(['text/plain'])

        self.assertEqual(msg.extract_content(), ('foo\n', [], False))

    def test_attached_text_plain(self):
        msg = construct_message([
            'multipart/mixed', [
                'text/plain',
                'text/plain',
            ],
        ])

        self.assertEqual(msg.extract_content(), (
            'foo\n',
            [('foo.txt', 'text/plain', 'foo\n')],
            False
        ))

    def test_multipart_mixed(self):
        msg = construct_message([
            'multipart/mixed', [
                'text/plain',
                'application/pdf',
            ],
        ])

        self.assertEqual(msg.extract_content(), (
            'foo\n',
            [('foo.pdf', 'application/pdf', b'foo\n')],
            False
        ))

    def test_multipart_alternative(self):
        msg = construct_message([
            'multipart/alternative', [
                'text/plain',
                'text/html',
            ],
        ])

        self.assertEqual(msg.extract_content(), (
            'foo\n',
            [('foo.html', 'text/html', '<html>foo</html>\n')],
            False
        ))

    def test_deep_multipart_alternative(self):
        msg = construct_message([
            'multipart/mixed', [
                'multipart/alternative', [
                    'text/plain',
                    'application/pdf',
                    'text/plain_2',
                    'text/html',
                ],
                'multipart/alternative', [
                    'text/plain_3',
                    'application/pdf_2',
                ],
            ],
        ])

        self.assertEqual(msg.extract_content(), (
            'foo2\n', [
                ('foo.pdf', 'application/pdf', b'foo\n'),
                ('foo.txt', 'text/plain', 'foo\n'),
                ('foo.html', 'text/html', '<html>foo</html>\n'),
                ('foo3.txt', 'text/plain', 'foo3\n'),
                ('foo2.pdf', 'application/pdf', b'foo2\n'),
            ],
            False
        ))

    def test_deep_multipart_alternative_ignore(self):
        msg = construct_message([
            'multipart/mixed', [
                'multipart/alternative', [
                    'text/plain',
                    'application/pdf',
                    'text/plain_2',
                    'text/html',
                ],
                'multipart/alternative', [
                    'text/plain_3',
                    'application/pdf_2',
                ],
            ],
        ])

        msg.extract_content(ignore_alternatives=True)
        self.assertEqual(msg.extract_content(ignore_alternatives=True), (
            'foo2\n', [
                ('foo3.txt', 'text/plain', 'foo3\n'),
                ('foo2.pdf', 'application/pdf', b'foo2\n'),
            ],
            False
        ))

    def test_signed_text(self):
        msg = construct_message([
            'multipart/signed', [
                'text/plain',
                'application/pgp-signature',
            ],
        ])

        self.assertEqual(msg.extract_content(), ('foo\n', [], False))

    def test_signed_attachemts(self):
        msg = construct_message([
            'multipart/signed', [
                'multipart/mixed', [
                    'text/plain',
                    'application/pdf',
                ],
                'application/pgp-signature',
            ],
        ])

        self.assertEqual(msg.extract_content(), (
            'foo\n',
            [('foo.pdf', 'application/pdf', b'foo\n')],
            False
        ))

    def test_attached_signature(self):
        msg = construct_message([
            'multipart/mixed', [
                'text/plain',
                'application/pgp-signature',
            ],
        ])

        self.assertEqual(msg.extract_content(), (
            'foo\n',
            [('foo.gpg', 'application/pgp-signature', b'foo\n')],
            False
        ))

    def test_rfc822_message(self):
        msg = construct_message([
            'multipart/mixed', [
                'message/rfc822',
            ],
        ])

        self.assertEqual(msg.extract_content(), (
            None,
            [('foo.eml', 'message/rfc822', 'Subject: foo\n\nfoo\n')],
            False
        ))

    def test_rfc822_message_unpack(self):
        msg = construct_message([
            'multipart/mixed', [
                'text/plain',
                'message/rfc822',
            ],
        ])

        self.assertEqual(msg.extract_content(unpack_rfc822=True), (
            'foo\n',
            [(None, 'text/plain', 'foo\n')],
            False
        ))


class PgpDetectRoundupMessageTests(TestCase):
    def test_pgp_message_signed(self):
        msg = message_from_string("""
            Content-Type: multipart/signed; micalg=pgp-sha1;
                    protocol="application/pgp-signature"

            Fake Body
        """)

        self.assertTrue(msg.pgp_signed())

    def test_pgp_message_not_signed(self):
        msg = message_from_string("""
            Content-Type: text/plain

            Fake Body
        """)

        self.assertFalse(msg.pgp_signed())

    def test_pgp_message_signed_protocol_missing(self):
        msg = message_from_string("""
            Content-Type: multipart/signed; micalg=pgp-sha1

            Fake Body
        """)

        self.assertFalse(msg.pgp_signed())

    def test_pgp_message_signed_protocol_invalid(self):
        msg = message_from_string("""
            Content-Type: multipart/signed;
                protocol="application/not-pgp-signature"

            Fake Body
        """)

        self.assertFalse(msg.pgp_signed())

    def test_pgp_message_encrypted(self):
        msg = message_from_string("""
            Content-Type: multipart/encrypted;
                protocol="application/pgp-encrypted"

            Fake Body
        """)

        self.assertTrue(msg.pgp_encrypted())

    def test_pgp_message_not_encrypted(self):
        msg = message_from_string("""
            Content-Type: text/plain

            Fake Body
        """)

        self.assertFalse(msg.pgp_encrypted())

    def test_pgp_message_encrypted_protocol_missing(self):
        msg = message_from_string("""
            Content-Type: multipart/encrypted

            Fake Body
        """)

        self.assertFalse(msg.pgp_encrypted())

    def test_pgp_message_encrypted_protocol_invalid(self):
        msg = message_from_string("""
            Content-Type: multipart/encrypted;
                protocol="application/not-pgp-encrypted"

            Fake Body
        """)

        self.assertFalse(msg.pgp_encrypted())

# TODO: testing of the verify_signature() and decrypt() RoundupMessage methods.
#   The whole PGP testing stuff seems a bit messy, so we will rely on the tests
#   in test_mailgw for the time being

Roundup Issue Tracker: http://roundup-tracker.org/