xref: /qemu/tests/qemu-iotests/149 (revision 49f95221) 
1#!/usr/bin/env python3
2# group: rw sudo
3#
4# Copyright (C) 2016 Red Hat, Inc.
5#
6# This program is free software; you can redistribute it and/or modify
7# it under the terms of the GNU General Public License as published by
8# the Free Software Foundation; either version 2 of the License, or
9# (at your option) any later version.
10#
11# This program is distributed in the hope that it will be useful,
12# but WITHOUT ANY WARRANTY; without even the implied warranty of
13# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14# GNU General Public License for more details.
15#
16# You should have received a copy of the GNU General Public License
17# along with this program.  If not, see <http://www.gnu.org/licenses/>.
18#
19# Creator/Owner: Daniel P. Berrange <berrange@redhat.com>
20#
21# Exercise the QEMU 'luks' block driver to validate interoperability
22# with the Linux dm-crypt + cryptsetup implementation
23
24import subprocess
25import os
26import os.path
27
28import base64
29
30import iotests
31
32
33class LUKSConfig(object):
34    """Represent configuration parameters for a single LUKS
35       setup to be tested"""
36
37    def __init__(self, name, cipher, keylen, mode, ivgen,
38                 ivgen_hash, hash, password=None, passwords=None):
39
40        self.name = name
41        self.cipher = cipher
42        self.keylen = keylen
43        self.mode = mode
44        self.ivgen = ivgen
45        self.ivgen_hash = ivgen_hash
46        self.hash = hash
47
48        if passwords is not None:
49            self.passwords = passwords
50        else:
51            self.passwords = {}
52
53            if password is None:
54                self.passwords["0"] = "123456"
55            else:
56                self.passwords["0"] = password
57
58    def __repr__(self):
59        return self.name
60
61    def image_name(self):
62        return "luks-%s.img" % self.name
63
64    def image_path(self):
65        return os.path.join(iotests.test_dir, self.image_name())
66
67    def device_name(self):
68        return "qiotest-145-%s" % self.name
69
70    def device_path(self):
71        return "/dev/mapper/" + self.device_name()
72
73    def first_password(self):
74        for i in range(8):
75            slot = str(i)
76            if slot in self.passwords:
77                return (self.passwords[slot], slot)
78        raise Exception("No password found")
79
80    def first_password_base64(self):
81        (pw, slot) = self.first_password()
82        return base64.b64encode(pw.encode('ascii')).decode('ascii')
83
84    def active_slots(self):
85        slots = []
86        for i in range(8):
87            slot = str(i)
88            if slot in self.passwords:
89                slots.append(slot)
90        return slots
91
92def verify_passwordless_sudo():
93    """Check whether sudo is configured to allow
94       password-less access to commands"""
95
96    args = ["sudo", "-n", "/bin/true"]
97
98    proc = subprocess.Popen(args,
99                            stdin=subprocess.PIPE,
100                            stdout=subprocess.PIPE,
101                            stderr=subprocess.STDOUT,
102                            universal_newlines=True)
103
104    msg = proc.communicate()[0]
105
106    if proc.returncode != 0:
107        iotests.notrun('requires password-less sudo access: %s' % msg)
108
109
110def cryptsetup(args, password=None):
111    """Run the cryptsetup command in batch mode"""
112
113    fullargs = ["sudo", "cryptsetup", "-q", "-v"]
114    fullargs.extend(args)
115
116    iotests.log(" ".join(fullargs), filters=[iotests.filter_test_dir])
117    proc = subprocess.Popen(fullargs,
118                            stdin=subprocess.PIPE,
119                            stdout=subprocess.PIPE,
120                            stderr=subprocess.STDOUT,
121                            universal_newlines=True)
122
123    msg = proc.communicate(password)[0]
124
125    if proc.returncode != 0:
126        raise Exception(msg)
127
128
129def cryptsetup_add_password(config, slot):
130    """Add another password to a LUKS key slot"""
131
132    (password, mainslot) = config.first_password()
133
134    pwfile = os.path.join(iotests.test_dir, "passwd.txt")
135    with open(pwfile, "w") as fh:
136        fh.write(config.passwords[slot])
137
138    try:
139        args = ["luksAddKey", config.image_path(),
140                "--key-slot", slot,
141                "--key-file", "-",
142                "--iter-time", "10",
143                pwfile]
144
145        cryptsetup(args, password)
146    finally:
147        os.unlink(pwfile)
148
149
150def cryptsetup_format(config):
151    """Format a new LUKS volume with cryptsetup, adding the
152    first key slot only"""
153
154    (password, slot) = config.first_password()
155
156    args = ["luksFormat", "--type", "luks1"]
157    cipher = config.cipher + "-" + config.mode + "-" + config.ivgen
158    if config.ivgen_hash is not None:
159        cipher = cipher + ":" + config.ivgen_hash
160    elif config.ivgen == "essiv":
161        cipher = cipher + ":" + "sha256"
162    args.extend(["--cipher", cipher])
163    if config.mode == "xts":
164        args.extend(["--key-size", str(config.keylen * 2)])
165    else:
166        args.extend(["--key-size", str(config.keylen)])
167    if config.hash is not None:
168        args.extend(["--hash", config.hash])
169    args.extend(["--key-slot", slot])
170    args.extend(["--key-file", "-"])
171    args.extend(["--iter-time", "10"])
172    args.append(config.image_path())
173
174    cryptsetup(args, password)
175
176
177def chown(config):
178    """Set the ownership of a open LUKS device to this user"""
179
180    path = config.device_path()
181
182    args = ["sudo", "chown", "%d:%d" % (os.getuid(), os.getgid()), path]
183    iotests.log(" ".join(args), filters=[iotests.filter_chown])
184    proc = subprocess.Popen(args,
185                            stdin=subprocess.PIPE,
186                            stdout=subprocess.PIPE,
187                            stderr=subprocess.STDOUT)
188
189    msg = proc.communicate()[0]
190
191    if proc.returncode != 0:
192        raise Exception(msg)
193
194
195def cryptsetup_open(config):
196    """Open an image as a LUKS device"""
197
198    (password, slot) = config.first_password()
199
200    args = ["luksOpen", config.image_path(), config.device_name()]
201
202    cryptsetup(args, password)
203
204
205def cryptsetup_close(config):
206    """Close an active LUKS device """
207
208    args = ["luksClose", config.device_name()]
209    cryptsetup(args)
210
211
212def delete_image(config):
213    """Delete a disk image"""
214
215    try:
216        os.unlink(config.image_path())
217        iotests.log("unlink %s" % config.image_path(),
218                    filters=[iotests.filter_test_dir])
219    except Exception as e:
220        pass
221
222
223def create_image(config, size_mb):
224    """Create a bare disk image with requested size"""
225
226    delete_image(config)
227    iotests.log("truncate %s --size %dMB" % (config.image_path(), size_mb),
228                filters=[iotests.filter_test_dir])
229    with open(config.image_path(), "w") as fn:
230        fn.truncate(size_mb * 1024 * 1024)
231
232
233def check_cipher_support(config, output):
234    """Check the output of qemu-img or qemu-io for mention of the respective
235    cipher algorithm being unsupported, and if so, skip this test.
236    (Returns `output` for convenience.)"""
237
238    if 'Unsupported cipher algorithm' in output:
239        iotests.notrun('Unsupported cipher algorithm '
240                       f'{config.cipher}-{config.keylen}-{config.mode}; '
241                       'consider configuring qemu with a different crypto '
242                       'backend')
243    return output
244
245def qemu_img_create(config, size_mb):
246    """Create and format a disk image with LUKS using qemu-img"""
247
248    opts = [
249        "key-secret=sec0",
250        "iter-time=10",
251        "cipher-alg=%s-%d" % (config.cipher, config.keylen),
252        "cipher-mode=%s" % config.mode,
253        "ivgen-alg=%s" % config.ivgen,
254        "hash-alg=%s" % config.hash,
255    ]
256    if config.ivgen_hash is not None:
257        opts.append("ivgen-hash-alg=%s" % config.ivgen_hash)
258
259    args = ["create", "-f", "luks",
260            "--object",
261            ("secret,id=sec0,data=%s,format=base64" %
262             config.first_password_base64()),
263            "-o", ",".join(opts),
264            config.image_path(),
265            "%dM" % size_mb]
266
267    iotests.log("qemu-img " + " ".join(args), filters=[iotests.filter_test_dir])
268    try:
269        iotests.qemu_img(*args)
270    except subprocess.CalledProcessError as exc:
271        check_cipher_support(config, exc.output)
272        raise
273
274def qemu_io_image_args(config, dev=False):
275    """Get the args for access an image or device with qemu-io"""
276
277    if dev:
278        return [
279            "--image-opts",
280            "driver=host_device,filename=%s" % config.device_path()]
281    else:
282        return [
283            "--object",
284            ("secret,id=sec0,data=%s,format=base64" %
285             config.first_password_base64()),
286            "--image-opts",
287            ("driver=luks,key-secret=sec0,file.filename=%s" %
288             config.image_path())]
289
290def qemu_io_write_pattern(config, pattern, offset_mb, size_mb, dev=False):
291    """Write a pattern of data to a LUKS image or device"""
292
293    if dev:
294        chown(config)
295    args = ["-c", "write -P 0x%x %dM %dM" % (pattern, offset_mb, size_mb)]
296    args.extend(qemu_io_image_args(config, dev))
297    iotests.log("qemu-io " + " ".join(args), filters=[iotests.filter_test_dir])
298    iotests.log(check_cipher_support(config, iotests.qemu_io(*args)),
299                filters=[iotests.filter_test_dir, iotests.filter_qemu_io])
300
301
302def qemu_io_read_pattern(config, pattern, offset_mb, size_mb, dev=False):
303    """Read a pattern of data to a LUKS image or device"""
304
305    if dev:
306        chown(config)
307    args = ["-c", "read -P 0x%x %dM %dM" % (pattern, offset_mb, size_mb)]
308    args.extend(qemu_io_image_args(config, dev))
309    iotests.log("qemu-io " + " ".join(args), filters=[iotests.filter_test_dir])
310    iotests.log(check_cipher_support(config, iotests.qemu_io(*args)),
311                filters=[iotests.filter_test_dir, iotests.filter_qemu_io])
312
313
314def test_once(config, qemu_img=False):
315    """Run the test with a desired LUKS configuration. Can either
316       use qemu-img for creating the initial volume, or cryptsetup,
317       in order to test interoperability in both directions"""
318
319    iotests.log("# ================= %s %s =================" % (
320        "qemu-img" if qemu_img else "dm-crypt", config))
321
322    oneKB = 1024
323    oneMB = oneKB * 1024
324    oneGB = oneMB * 1024
325    oneTB = oneGB * 1024
326
327    # 4 TB, so that we pass the 32-bit sector number boundary.
328    # Important for testing correctness of some IV generators
329    # The files are sparse, so not actually using this much space
330    image_size = 4 * oneTB
331    if qemu_img:
332        iotests.log("# Create image")
333        qemu_img_create(config, image_size // oneMB)
334    else:
335        iotests.log("# Create image")
336        create_image(config, image_size // oneMB)
337
338    lowOffsetMB = 100
339    highOffsetMB = 3 * oneTB // oneMB
340
341    try:
342        if not qemu_img:
343            iotests.log("# Format image")
344            cryptsetup_format(config)
345
346            for slot in config.active_slots()[1:]:
347                iotests.log("# Add password slot %s" % slot)
348                cryptsetup_add_password(config, slot)
349
350        # First we'll open the image using cryptsetup and write a
351        # known pattern of data that we'll then verify with QEMU
352
353        iotests.log("# Open dev")
354        cryptsetup_open(config)
355
356        try:
357            iotests.log("# Write test pattern 0xa7")
358            qemu_io_write_pattern(config, 0xa7, lowOffsetMB, 10, dev=True)
359            iotests.log("# Write test pattern 0x13")
360            qemu_io_write_pattern(config, 0x13, highOffsetMB, 10, dev=True)
361        finally:
362            iotests.log("# Close dev")
363            cryptsetup_close(config)
364
365        # Ok, now we're using QEMU to verify the pattern just
366        # written via dm-crypt
367
368        iotests.log("# Read test pattern 0xa7")
369        qemu_io_read_pattern(config, 0xa7, lowOffsetMB, 10, dev=False)
370        iotests.log("# Read test pattern 0x13")
371        qemu_io_read_pattern(config, 0x13, highOffsetMB, 10, dev=False)
372
373
374        # Write a new pattern to the image, which we'll later
375        # verify with dm-crypt
376        iotests.log("# Write test pattern 0x91")
377        qemu_io_write_pattern(config, 0x91, lowOffsetMB, 10, dev=False)
378        iotests.log("# Write test pattern 0x5e")
379        qemu_io_write_pattern(config, 0x5e, highOffsetMB, 10, dev=False)
380
381
382        # Now we're opening the image with dm-crypt once more
383        # and verifying what QEMU wrote, completing the circle
384        iotests.log("# Open dev")
385        cryptsetup_open(config)
386
387        try:
388            iotests.log("# Read test pattern 0x91")
389            qemu_io_read_pattern(config, 0x91, lowOffsetMB, 10, dev=True)
390            iotests.log("# Read test pattern 0x5e")
391            qemu_io_read_pattern(config, 0x5e, highOffsetMB, 10, dev=True)
392        finally:
393            iotests.log("# Close dev")
394            cryptsetup_close(config)
395    finally:
396        iotests.log("# Delete image")
397        delete_image(config)
398        print()
399
400
401# Obviously we only work with the luks image format
402iotests.script_initialize(supported_fmts=['luks'])
403
404# We need sudo in order to run cryptsetup to create
405# dm-crypt devices. This is safe to use on any
406# machine, since all dm-crypt devices are backed
407# by newly created plain files, and have a dm-crypt
408# name prefix of 'qiotest' to avoid clashing with
409# user LUKS volumes
410verify_passwordless_sudo()
411
412
413# If we look at all permutations of cipher, key size,
414# mode, ivgen, hash, there are ~1000 possible configs.
415#
416# We certainly don't want/need to test every permutation
417# to get good validation of interoperability between QEMU
418# and dm-crypt/cryptsetup.
419#
420# The configs below are a representative set that aim to
421# exercise each axis of configurability.
422#
423configs = [
424    # A common LUKS default
425    LUKSConfig("aes-256-xts-plain64-sha1",
426               "aes", 256, "xts", "plain64", None, "sha1"),
427
428
429    # LUKS default but diff ciphers
430    LUKSConfig("twofish-256-xts-plain64-sha1",
431               "twofish", 256, "xts", "plain64", None, "sha1"),
432    LUKSConfig("serpent-256-xts-plain64-sha1",
433               "serpent", 256, "xts", "plain64", None, "sha1"),
434    # Should really be xts, but kernel doesn't support xts+cast5
435    # nor does it do essiv+cast5
436    LUKSConfig("cast5-128-cbc-plain64-sha1",
437               "cast5", 128, "cbc", "plain64", None, "sha1"),
438    LUKSConfig("cast6-256-xts-plain64-sha1",
439               "cast6", 256, "xts", "plain64", None, "sha1"),
440
441
442    # LUKS default but diff modes / ivgens
443    LUKSConfig("aes-256-cbc-plain-sha1",
444               "aes", 256, "cbc", "plain", None, "sha1"),
445    LUKSConfig("aes-256-cbc-plain64-sha1",
446               "aes", 256, "cbc", "plain64", None, "sha1"),
447    LUKSConfig("aes-256-cbc-essiv-sha256-sha1",
448               "aes", 256, "cbc", "essiv", "sha256", "sha1"),
449    LUKSConfig("aes-256-xts-essiv-sha256-sha1",
450               "aes", 256, "xts", "essiv", "sha256", "sha1"),
451
452
453    # LUKS default but smaller key sizes
454    LUKSConfig("aes-128-xts-plain64-sha256-sha1",
455               "aes", 128, "xts", "plain64", None, "sha1"),
456    LUKSConfig("aes-192-xts-plain64-sha256-sha1",
457               "aes", 192, "xts", "plain64", None, "sha1"),
458
459    LUKSConfig("twofish-128-xts-plain64-sha1",
460               "twofish", 128, "xts", "plain64", None, "sha1"),
461    LUKSConfig("twofish-192-xts-plain64-sha1",
462               "twofish", 192, "xts", "plain64", None, "sha1"),
463
464    LUKSConfig("serpent-128-xts-plain64-sha1",
465               "serpent", 128, "xts", "plain64", None, "sha1"),
466    LUKSConfig("serpent-192-xts-plain64-sha1",
467               "serpent", 192, "xts", "plain64", None, "sha1"),
468
469    LUKSConfig("cast6-128-xts-plain64-sha1",
470               "cast6", 128, "xts", "plain", None, "sha1"),
471    LUKSConfig("cast6-192-xts-plain64-sha1",
472               "cast6", 192, "xts", "plain64", None, "sha1"),
473
474
475    # LUKS default but diff hash
476    LUKSConfig("aes-256-xts-plain64-sha224",
477               "aes", 256, "xts", "plain64", None, "sha224"),
478    LUKSConfig("aes-256-xts-plain64-sha256",
479               "aes", 256, "xts", "plain64", None, "sha256"),
480    LUKSConfig("aes-256-xts-plain64-sha384",
481               "aes", 256, "xts", "plain64", None, "sha384"),
482    LUKSConfig("aes-256-xts-plain64-sha512",
483               "aes", 256, "xts", "plain64", None, "sha512"),
484    LUKSConfig("aes-256-xts-plain64-ripemd160",
485               "aes", 256, "xts", "plain64", None, "ripemd160"),
486
487    # Password in slot 3
488    LUKSConfig("aes-256-xts-plain-sha1-pwslot3",
489               "aes", 256, "xts", "plain", None, "sha1",
490               passwords={
491                   "3": "slot3",
492               }),
493
494    # Passwords in every slot
495    LUKSConfig("aes-256-xts-plain-sha1-pwallslots",
496               "aes", 256, "xts", "plain", None, "sha1",
497               passwords={
498                   "0": "slot1",
499                   "1": "slot1",
500                   "2": "slot2",
501                   "3": "slot3",
502                   "4": "slot4",
503                   "5": "slot5",
504                   "6": "slot6",
505                   "7": "slot7",
506               }),
507
508    # Check handling of default hash alg (sha256) with essiv
509    LUKSConfig("aes-256-cbc-essiv-auto-sha1",
510               "aes", 256, "cbc", "essiv", None, "sha1"),
511
512    # Check that a useless hash provided for 'plain64' iv gen
513    # is ignored and no error raised
514    LUKSConfig("aes-256-cbc-plain64-sha256-sha1",
515               "aes", 256, "cbc", "plain64", "sha256", "sha1"),
516
517]
518
519blacklist = [
520    # We don't have a cast-6 cipher impl for QEMU yet
521    "cast6-256-xts-plain64-sha1",
522    "cast6-128-xts-plain64-sha1",
523    "cast6-192-xts-plain64-sha1",
524
525    # GCrypt doesn't support Twofish with 192 bit key
526    "twofish-192-xts-plain64-sha1",
527]
528
529whitelist = []
530if "LUKS_CONFIG" in os.environ:
531    whitelist = os.environ["LUKS_CONFIG"].split(",")
532
533for config in configs:
534    if config.name in blacklist:
535        iotests.log("Skipping %s in blacklist" % config.name)
536        continue
537
538    if len(whitelist) > 0 and config.name not in whitelist:
539        iotests.log("Skipping %s not in whitelist" % config.name)
540        continue
541
542    test_once(config, qemu_img=False)
543
544    # XXX we should support setting passwords in a non-0
545    # key slot with 'qemu-img create' in future
546    (pw, slot) = config.first_password()
547    if slot == "0":
548        test_once(config, qemu_img=True)
549