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
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
|
import io
import os
import unittest
import hashlib
from apkInspector.extract import extract_file_based_on_header_info
from apkInspector.headers import EndOfCentralDirectoryRecord, CentralDirectory, ZipEntry, LocalHeaderRecord
from apkInspector.indicators import apk_tampering_check
from apkInspector.axml import get_manifest
class ApkInspectorTestCase(unittest.TestCase):
def setUp(self):
# Open the test APK files here and set them as instance variables
test_dir = os.path.dirname(os.path.abspath(__file__))
apk_path_orig = os.path.join(test_dir, 'res', 'minimal_orig.apk')
apk_path_mod = os.path.join(test_dir, 'res', 'minimal_def_mod.apk')
self.apk_orig = open(apk_path_orig, "rb")
self.apk_mod = open(apk_path_mod, "rb")
def tearDown(self):
# Close the test APK files in the tearDown method
self.apk_orig.close()
self.apk_mod.close()
def test_find_eocd(self):
eocd_orig = EndOfCentralDirectoryRecord.parse(self.apk_orig).to_dict()
eocd_mod = EndOfCentralDirectoryRecord.parse(self.apk_mod).to_dict()
orig = {'signature': b'PK\x05\x06', 'number_of_this_disk': 0, 'disk_where_central_directory_starts': 0,
'number_of_central_directory_records_on_this_disk': 23, 'total_number_of_central_directory_records': 23,
'size_of_central_directory': 1317, 'offset_of_start_of_central_directory': 151552, 'comment_length': 0,
'comment': ''}
mod = {'signature': b'PK\x05\x06', 'number_of_this_disk': 0, 'disk_where_central_directory_starts': 0,
'number_of_central_directory_records_on_this_disk': 24, 'total_number_of_central_directory_records': 24,
'size_of_central_directory': 1420, 'offset_of_start_of_central_directory': 151552, 'comment_length': 0,
'comment': ''}
self.assertEqual(eocd_orig, orig)
self.assertEqual(eocd_mod, mod)
def test_find_eocd_at_offset_1026(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
expected_hash = "5599105c7d7a09e2d87c39282ae92c2c76c09eb4849ddf8bc27137b294e0afd0"
with open(os.path.join(test_dir, 'res', 'eocd_at_offset_1026.apk'), 'rb') as apk_file:
eocd = EndOfCentralDirectoryRecord.parse(apk_file).to_dict()
self.assertEqual(expected_hash, hashlib.sha256(str(eocd).encode('utf-8')).hexdigest())
def test_eocd_from_dict(self):
mod = {'signature': b'PK\x05\x06', 'number_of_this_disk': 0, 'disk_where_central_directory_starts': 0,
'number_of_central_directory_records_on_this_disk': 24, 'total_number_of_central_directory_records': 24,
'size_of_central_directory': 1420, 'offset_of_start_of_central_directory': 151552, 'comment_length': 0,
'comment': ''}
eocd_instance = EndOfCentralDirectoryRecord.from_dict(mod)
self.assertEqual(eocd_instance.size_of_central_directory, 1420)
self.assertEqual(eocd_instance.offset_of_start_of_central_directory, 151552)
self.assertEqual(eocd_instance.total_number_of_central_directory_records, 24)
def test_parse_central_directory(self):
hash_orig = 'ae178cbf4ccf180d39740060ab3bfbdfbbd8754c8a154f46d67a8ff7966a6d70'
hash_mod = '7e6c1667c1231f5b5c667be7220775cf7a3c05746aee6e392db1f696c4ce8eea'
central_directory_entries_orig = CentralDirectory.parse(self.apk_orig).to_dict()
central_directory_entries_mod = CentralDirectory.parse(self.apk_mod).to_dict()
tocheck_orig = hashlib.sha256(str(central_directory_entries_orig).encode('utf-8')).hexdigest()
tocheck_mod = hashlib.sha256(str(central_directory_entries_mod).encode('utf-8')).hexdigest()
self.assertEqual(tocheck_orig, hash_orig)
self.assertEqual(tocheck_mod, hash_mod)
def test_central_directory_from_dict(self):
cd_orig_dict = {'AndroidManifest.xml': {'version_made_by': 788, 'version_needed_to_extract': 20,
'general_purpose_bit_flag': 0, 'compression_method': 0,
'file_last_modification_time': 2081, 'file_last_modification_date': 545,
'crc32_of_uncompressed_data': 998929674, 'compressed_size': 2084,
'uncompressed_size': 2084, 'file_name_length': 19,
'extra_field_length': 0, 'file_comment_length': 0,
'disk_number_where_file_starts': 0, 'internal_file_attributes': 0,
'external_file_attributes': 2176057344,
'relative_offset_of_local_file_header': 0,
'filename': 'AndroidManifest.xml', 'extra_field': '',
'file_comment': '', 'offset_in_central_directory': 151552},
'classes.dex': {'version_made_by': 788, 'version_needed_to_extract': 20,
'general_purpose_bit_flag': 0, 'compression_method': 8,
'file_last_modification_time': 2081, 'file_last_modification_date': 545,
'crc32_of_uncompressed_data': 1432748217, 'compressed_size': 616,
'uncompressed_size': 1032, 'file_name_length': 11, 'extra_field_length': 0,
'file_comment_length': 0, 'disk_number_where_file_starts': 0,
'internal_file_attributes': 0, 'external_file_attributes': 2175008768,
'relative_offset_of_local_file_header': 2136, 'filename': 'classes.dex',
'extra_field': '', 'file_comment': '', 'offset_in_central_directory': 151617}}
cd_dir_instance = CentralDirectory.from_dict(cd_orig_dict)
self.assertEqual(cd_dir_instance.entries['AndroidManifest.xml'].to_dict()['file_last_modification_time'], 2081)
def test_parse_local_header(self):
ze_orig = ZipEntry.parse_single(self.apk_orig, "AndroidManifest.xml")
ze_mod = ZipEntry.parse_single(self.apk_mod, "AndroidManifest.xml")
comp_orig = {'version_needed_to_extract': 20, 'general_purpose_bit_flag': 0, 'compression_method': 0,
'file_last_modification_time': 2081, 'file_last_modification_date': 545,
'crc32_of_uncompressed_data': 998929674, 'compressed_size': 2084, 'uncompressed_size': 2084,
'file_name_length': 19, 'extra_field_length': 3, 'filename': 'AndroidManifest.xml',
'extra_field': '\x00\x00\x00'}
comp_mod = {'version_needed_to_extract': 20, 'general_purpose_bit_flag': 0, 'compression_method': 30208,
'file_last_modification_time': 45686, 'file_last_modification_date': 22321,
'crc32_of_uncompressed_data': 2768741858, 'compressed_size': 2084, 'uncompressed_size': 2084,
'file_name_length': 19, 'extra_field_length': 0, 'filename': 'AndroidManifest.xml',
'extra_field': ''}
self.assertEqual(ze_orig.local_headers["AndroidManifest.xml"].to_dict(), comp_orig)
self.assertEqual(ze_mod.local_headers["AndroidManifest.xml"].to_dict(), comp_mod)
def test_local_header_from_dict(self):
andro_local_dict = {'version_needed_to_extract': 20, 'general_purpose_bit_flag': 0, 'compression_method': 30208,
'file_last_modification_time': 45686, 'file_last_modification_date': 22321,
'crc32_of_uncompressed_data': 2768741858, 'compressed_size': 2084,
'uncompressed_size': 2084, 'file_name_length': 19, 'extra_field_length': 0,
'filename': 'AndroidManifest.xml', 'extra_field': ''}
local_instance = LocalHeaderRecord.from_dict(andro_local_dict)
self.assertEqual(local_instance.filename, 'AndroidManifest.xml')
self.assertEqual(local_instance.compression_method, 30208)
def test_extract_file_based_on_header_info(self):
zipentry = ZipEntry.parse(self.apk_orig)
cd_h_of_file = zipentry.get_central_directory_entry_dict("AndroidManifest.xml")
local_header_of_file = zipentry.get_local_header_dict("AndroidManifest.xml")
ext_hash = '5f37db22380177c20804d8602ffbdc048caeaa851412ab127e6fe1c9a9b1c78e'
androidManifest_extracted = \
extract_file_based_on_header_info(self.apk_orig, local_header_of_file, cd_h_of_file)[0]
self.assertEqual(hashlib.sha256(androidManifest_extracted).hexdigest(), ext_hash)
def test_extract_modified_file_based_on_header_info(self):
zipentry = ZipEntry.parse(self.apk_mod)
cd_h_of_file = zipentry.get_central_directory_entry_dict("AndroidManifest.xml")
local_header_of_file = zipentry.get_local_header_dict("AndroidManifest.xml")
ext_hash = '5dc10a071f28ef25c6caa3cd3aef0d93985dacb1dba08ca46632ba655129e503'
androidManifest_extracted = extract_file_based_on_header_info(self.apk_mod, local_header_of_file, cd_h_of_file)[
0]
self.assertEqual(hashlib.sha256(androidManifest_extracted).hexdigest(), ext_hash)
def test_extract_when_zero_size_and_extra_field_present(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
with open(os.path.join(test_dir, 'res', 'minimal_SIZE_ExtraField.apk'), 'rb') as apk_file:
zipentry = ZipEntry.parse(apk_file)
cd_h_of_file = zipentry.get_central_directory_entry_dict("AndroidManifest.xml")
local_header_of_file = zipentry.get_local_header_dict("AndroidManifest.xml")
ext_hash = '5f37db22380177c20804d8602ffbdc048caeaa851412ab127e6fe1c9a9b1c78e'
androidManifest_extracted = \
extract_file_based_on_header_info(apk_file, local_header_of_file, cd_h_of_file)[0]
self.assertEqual(hashlib.sha256(androidManifest_extracted).hexdigest(), ext_hash)
def test_zipentry_raw_and_path(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
apk_file = os.path.join(test_dir, 'res', 'minimal_orig.apk')
zipentry_path = ZipEntry.parse(apk_file, raw=False)
zipentry_raw = ZipEntry.parse(self.apk_orig)
self.assertEqual(hashlib.sha256(zipentry_path.zip.read()).hexdigest(),
hashlib.sha256(zipentry_raw.zip.read()).hexdigest())
def test_zipentry_read(self):
zipentry = ZipEntry.parse(self.apk_orig)
manifest = zipentry.read("AndroidManifest.xml")
self.assertEqual(hashlib.sha256(manifest).hexdigest(),
"5f37db22380177c20804d8602ffbdc048caeaa851412ab127e6fe1c9a9b1c78e")
def test_zipentry_read_non_existing(self):
zipentry = ZipEntry.parse(self.apk_orig)
with self.assertRaises(KeyError):
zipentry.read("non-existing-entry")
def test_zipentry_central_non_existing(self):
zipentry = ZipEntry.parse(self.apk_orig)
with self.assertRaises(KeyError) as context:
zipentry.get_central_directory_entry_dict("non-existing-entry")
def test_zipentry_to_dict(self):
zipentry = ZipEntry.parse(self.apk_mod)
self.assertEqual(hashlib.sha256(str(zipentry.to_dict()).encode('utf-8')).hexdigest(),
"fbddeffe316446f47e49abe1dbf03fa2a8c0f5af3ad965609368b63932683a2d")
def test_zipentry_infolist(self):
zipentry = ZipEntry.parse(self.apk_mod)
self.assertEqual(set(zipentry.infolist().keys()),
{'res/13.webp', 'res/Nt.webp', 'res/j_.webp', 'classes.dex', 'AndroidManifest.xml',
'res/sK.webp', 'res/u5.webp', 'res/0w.xml', 'res/fq.webp', 'res/qs.webp', 'res/MO.webp',
'res/BW.xml', 'resources.arsc', 'res/d2.webp', 'res/iE.webp', 'res/-6.webp', 'res/5c.webp',
'res/Fd.xml', 'res/yw.webp', 'res/0K.xml', 'res/Qr.xml', 'res/9Q.webp',
'META-INF/com/android/build/gradle/app-metadata.properties', 'res/Sn.webp'})
def test_zipentry_namelist(self):
zipentry = ZipEntry.parse(self.apk_mod)
self.assertEqual(zipentry.namelist(), ['AndroidManifest.xml', 'classes.dex', 'resources.arsc',
'META-INF/com/android/build/gradle/app-metadata.properties',
'res/BW.xml', 'res/9Q.webp', 'res/Sn.webp', 'res/5c.webp', 'res/yw.webp',
'res/Nt.webp', 'res/MO.webp', 'res/-6.webp', 'res/j_.webp', 'res/0K.xml',
'res/Qr.xml', 'res/d2.webp', 'res/fq.webp', 'res/0w.xml', 'res/iE.webp',
'res/qs.webp', 'res/Fd.xml', 'res/u5.webp', 'res/13.webp',
'res/sK.webp'])
def test_android_manifest_decoding_orig(self):
zipentry = ZipEntry.parse(self.apk_orig)
cd_h_of_file = zipentry.get_central_directory_entry_dict("AndroidManifest.xml")
local_header_of_file = zipentry.get_local_header_dict("AndroidManifest.xml")
extracted_data = io.BytesIO(
extract_file_based_on_header_info(self.apk_orig, local_header_of_file, cd_h_of_file)[0])
manifest = get_manifest(extracted_data)
manifest_orig = '2846a9e29eb2d75623246440ef02d5a098cde7d21e3948b3ece3c68e3bae13f3'
self.assertEqual(hashlib.sha256(str(manifest).encode('utf-8')).hexdigest(), manifest_orig)
def test_android_manifest_decoding_mod(self):
zipentry = ZipEntry.parse(self.apk_mod)
cd_h_of_file = zipentry.get_central_directory_entry_dict("AndroidManifest.xml")
local_header_of_file = zipentry.get_local_header_dict("AndroidManifest.xml")
extracted_data = io.BytesIO(
extract_file_based_on_header_info(self.apk_mod, local_header_of_file, cd_h_of_file)[0])
manifest = get_manifest(extracted_data)
manifest_mod = '2846a9e29eb2d75623246440ef02d5a098cde7d21e3948b3ece3c68e3bae13f3'
self.assertEqual(hashlib.sha256(str(manifest).encode('utf-8')).hexdigest(), manifest_mod)
def test_tampering_indicators(self):
orig_val = {'zip tampering': {}, 'manifest tampering': {}}
mod_val = {'zip tampering': {'AndroidManifest.xml': {'central compression method': 30208, 'local compression '
'method': 30208,
'actual compression method': 'STORED_TAMPERED'}},
'manifest tampering': {'unexpected_starting_signature_of_androidmanifest': '0x0', 'string_pool': {
'string_count': 49, 'real_string_count': 32}}}
orig = apk_tampering_check(self.apk_orig, False)
mod = apk_tampering_check(self.apk_mod, False)
self.assertEqual(orig, orig_val)
self.assertEqual(mod, mod_val)
def test_tampering_indicators_size(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
expected = {'zip tampering': {'AndroidManifest.xml': {
'differing headers': ['compressed_size', 'extra_field', 'extra_field_length', 'uncompressed_size']}},
'manifest tampering': {}}
with open(os.path.join(test_dir, 'res', 'minimal_SIZE_ExtraField.apk'), 'rb') as apk_file:
res = apk_tampering_check(apk_file, True)
self.assertEqual(res, expected)
def test_tampering_zero_end_ns(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
expected = {'zip tampering': {}, 'manifest tampering': {'zero_size_header_for_namespace_end_nodes': True}}
with open(os.path.join(test_dir, 'res', 'minimal_zero_sized_end_ns.apk'), 'rb') as apk_file:
res = apk_tampering_check(apk_file, False)
self.assertEqual(res, expected)
def test_inconsistencies_in_central_local_entries(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
with open(os.path.join(test_dir, 'res', 'truncated-cd.apk'), "rb") as apk_file:
res = apk_tampering_check(apk_file, False)
self.assertIn('classes.dex', res['zip tampering']['unique_entries'])
self.assertIn('classes.deP', res['zip tampering']['unique_entries'])
def test_manifest_invalid_res_map(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
with open(os.path.join(test_dir, 'res', 'manifest', 'AndroidManifest_resource_map_not_found.xml'), "rb") as mf:
with self.assertRaises(ValueError) as context:
get_manifest(io.BytesIO(mf.read()))
self.assertEqual(str(context.exception), "Resource Map header was not detected.")
def test_manifest_cdata(self):
test_dir = os.path.dirname(os.path.abspath(__file__))
with open(os.path.join(test_dir, 'res', 'manifest', 'AndroidManifest_CDATA.xml'), "rb") as mf:
mnfst = get_manifest(io.BytesIO(mf.read()))
lines = mnfst.split('\n')
self.assertEqual(lines[5], '<intent-filter>com.erev0s.minimal<action android:name="android.intent.action.MAIN">')
if __name__ == '__main__':
unittest.main()
|
