xref: /openbmc/qemu/tests/qemu-iotests/149 (revision cbb45ff0) 
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    iotests.log(check_cipher_support(config, iotests.qemu_img_pipe(*args)),
269                filters=[iotests.filter_test_dir])
270
271def qemu_io_image_args(config, dev=False):
272    """Get the args for access an image or device with qemu-io"""
273
274    if dev:
275        return [
276            "--image-opts",
277            "driver=host_device,filename=%s" % config.device_path()]
278    else:
279        return [
280            "--object",
281            ("secret,id=sec0,data=%s,format=base64" %
282             config.first_password_base64()),
283            "--image-opts",
284            ("driver=luks,key-secret=sec0,file.filename=%s" %
285             config.image_path())]
286
287def qemu_io_write_pattern(config, pattern, offset_mb, size_mb, dev=False):
288    """Write a pattern of data to a LUKS image or device"""
289
290    if dev:
291        chown(config)
292    args = ["-c", "write -P 0x%x %dM %dM" % (pattern, offset_mb, size_mb)]
293    args.extend(qemu_io_image_args(config, dev))
294    iotests.log("qemu-io " + " ".join(args), filters=[iotests.filter_test_dir])
295    iotests.log(check_cipher_support(config, iotests.qemu_io(*args)),
296                filters=[iotests.filter_test_dir, iotests.filter_qemu_io])
297
298
299def qemu_io_read_pattern(config, pattern, offset_mb, size_mb, dev=False):
300    """Read a pattern of data to a LUKS image or device"""
301
302    if dev:
303        chown(config)
304    args = ["-c", "read -P 0x%x %dM %dM" % (pattern, offset_mb, size_mb)]
305    args.extend(qemu_io_image_args(config, dev))
306    iotests.log("qemu-io " + " ".join(args), filters=[iotests.filter_test_dir])
307    iotests.log(check_cipher_support(config, iotests.qemu_io(*args)),
308                filters=[iotests.filter_test_dir, iotests.filter_qemu_io])
309
310
311def test_once(config, qemu_img=False):
312    """Run the test with a desired LUKS configuration. Can either
313       use qemu-img for creating the initial volume, or cryptsetup,
314       in order to test interoperability in both directions"""
315
316    iotests.log("# ================= %s %s =================" % (
317        "qemu-img" if qemu_img else "dm-crypt", config))
318
319    oneKB = 1024
320    oneMB = oneKB * 1024
321    oneGB = oneMB * 1024
322    oneTB = oneGB * 1024
323
324    # 4 TB, so that we pass the 32-bit sector number boundary.
325    # Important for testing correctness of some IV generators
326    # The files are sparse, so not actually using this much space
327    image_size = 4 * oneTB
328    if qemu_img:
329        iotests.log("# Create image")
330        qemu_img_create(config, image_size // oneMB)
331    else:
332        iotests.log("# Create image")
333        create_image(config, image_size // oneMB)
334
335    lowOffsetMB = 100
336    highOffsetMB = 3 * oneTB // oneMB
337
338    try:
339        if not qemu_img:
340            iotests.log("# Format image")
341            cryptsetup_format(config)
342
343            for slot in config.active_slots()[1:]:
344                iotests.log("# Add password slot %s" % slot)
345                cryptsetup_add_password(config, slot)
346
347        # First we'll open the image using cryptsetup and write a
348        # known pattern of data that we'll then verify with QEMU
349
350        iotests.log("# Open dev")
351        cryptsetup_open(config)
352
353        try:
354            iotests.log("# Write test pattern 0xa7")
355            qemu_io_write_pattern(config, 0xa7, lowOffsetMB, 10, dev=True)
356            iotests.log("# Write test pattern 0x13")
357            qemu_io_write_pattern(config, 0x13, highOffsetMB, 10, dev=True)
358        finally:
359            iotests.log("# Close dev")
360            cryptsetup_close(config)
361
362        # Ok, now we're using QEMU to verify the pattern just
363        # written via dm-crypt
364
365        iotests.log("# Read test pattern 0xa7")
366        qemu_io_read_pattern(config, 0xa7, lowOffsetMB, 10, dev=False)
367        iotests.log("# Read test pattern 0x13")
368        qemu_io_read_pattern(config, 0x13, highOffsetMB, 10, dev=False)
369
370
371        # Write a new pattern to the image, which we'll later
372        # verify with dm-crypt
373        iotests.log("# Write test pattern 0x91")
374        qemu_io_write_pattern(config, 0x91, lowOffsetMB, 10, dev=False)
375        iotests.log("# Write test pattern 0x5e")
376        qemu_io_write_pattern(config, 0x5e, highOffsetMB, 10, dev=False)
377
378
379        # Now we're opening the image with dm-crypt once more
380        # and verifying what QEMU wrote, completing the circle
381        iotests.log("# Open dev")
382        cryptsetup_open(config)
383
384        try:
385            iotests.log("# Read test pattern 0x91")
386            qemu_io_read_pattern(config, 0x91, lowOffsetMB, 10, dev=True)
387            iotests.log("# Read test pattern 0x5e")
388            qemu_io_read_pattern(config, 0x5e, highOffsetMB, 10, dev=True)
389        finally:
390            iotests.log("# Close dev")
391            cryptsetup_close(config)
392    finally:
393        iotests.log("# Delete image")
394        delete_image(config)
395        print()
396
397
398# Obviously we only work with the luks image format
399iotests.script_initialize(supported_fmts=['luks'])
400
401# We need sudo in order to run cryptsetup to create
402# dm-crypt devices. This is safe to use on any
403# machine, since all dm-crypt devices are backed
404# by newly created plain files, and have a dm-crypt
405# name prefix of 'qiotest' to avoid clashing with
406# user LUKS volumes
407verify_passwordless_sudo()
408
409
410# If we look at all permutations of cipher, key size,
411# mode, ivgen, hash, there are ~1000 possible configs.
412#
413# We certainly don't want/need to test every permutation
414# to get good validation of interoperability between QEMU
415# and dm-crypt/cryptsetup.
416#
417# The configs below are a representative set that aim to
418# exercise each axis of configurability.
419#
420configs = [
421    # A common LUKS default
422    LUKSConfig("aes-256-xts-plain64-sha1",
423               "aes", 256, "xts", "plain64", None, "sha1"),
424
425
426    # LUKS default but diff ciphers
427    LUKSConfig("twofish-256-xts-plain64-sha1",
428               "twofish", 256, "xts", "plain64", None, "sha1"),
429    LUKSConfig("serpent-256-xts-plain64-sha1",
430               "serpent", 256, "xts", "plain64", None, "sha1"),
431    # Should really be xts, but kernel doesn't support xts+cast5
432    # nor does it do essiv+cast5
433    LUKSConfig("cast5-128-cbc-plain64-sha1",
434               "cast5", 128, "cbc", "plain64", None, "sha1"),
435    LUKSConfig("cast6-256-xts-plain64-sha1",
436               "cast6", 256, "xts", "plain64", None, "sha1"),
437
438
439    # LUKS default but diff modes / ivgens
440    LUKSConfig("aes-256-cbc-plain-sha1",
441               "aes", 256, "cbc", "plain", None, "sha1"),
442    LUKSConfig("aes-256-cbc-plain64-sha1",
443               "aes", 256, "cbc", "plain64", None, "sha1"),
444    LUKSConfig("aes-256-cbc-essiv-sha256-sha1",
445               "aes", 256, "cbc", "essiv", "sha256", "sha1"),
446    LUKSConfig("aes-256-xts-essiv-sha256-sha1",
447               "aes", 256, "xts", "essiv", "sha256", "sha1"),
448
449
450    # LUKS default but smaller key sizes
451    LUKSConfig("aes-128-xts-plain64-sha256-sha1",
452               "aes", 128, "xts", "plain64", None, "sha1"),
453    LUKSConfig("aes-192-xts-plain64-sha256-sha1",
454               "aes", 192, "xts", "plain64", None, "sha1"),
455
456    LUKSConfig("twofish-128-xts-plain64-sha1",
457               "twofish", 128, "xts", "plain64", None, "sha1"),
458    LUKSConfig("twofish-192-xts-plain64-sha1",
459               "twofish", 192, "xts", "plain64", None, "sha1"),
460
461    LUKSConfig("serpent-128-xts-plain64-sha1",
462               "serpent", 128, "xts", "plain64", None, "sha1"),
463    LUKSConfig("serpent-192-xts-plain64-sha1",
464               "serpent", 192, "xts", "plain64", None, "sha1"),
465
466    LUKSConfig("cast6-128-xts-plain64-sha1",
467               "cast6", 128, "xts", "plain", None, "sha1"),
468    LUKSConfig("cast6-192-xts-plain64-sha1",
469               "cast6", 192, "xts", "plain64", None, "sha1"),
470
471
472    # LUKS default but diff hash
473    LUKSConfig("aes-256-xts-plain64-sha224",
474               "aes", 256, "xts", "plain64", None, "sha224"),
475    LUKSConfig("aes-256-xts-plain64-sha256",
476               "aes", 256, "xts", "plain64", None, "sha256"),
477    LUKSConfig("aes-256-xts-plain64-sha384",
478               "aes", 256, "xts", "plain64", None, "sha384"),
479    LUKSConfig("aes-256-xts-plain64-sha512",
480               "aes", 256, "xts", "plain64", None, "sha512"),
481    LUKSConfig("aes-256-xts-plain64-ripemd160",
482               "aes", 256, "xts", "plain64", None, "ripemd160"),
483
484    # Password in slot 3
485    LUKSConfig("aes-256-xts-plain-sha1-pwslot3",
486               "aes", 256, "xts", "plain", None, "sha1",
487               passwords={
488                   "3": "slot3",
489               }),
490
491    # Passwords in every slot
492    LUKSConfig("aes-256-xts-plain-sha1-pwallslots",
493               "aes", 256, "xts", "plain", None, "sha1",
494               passwords={
495                   "0": "slot1",
496                   "1": "slot1",
497                   "2": "slot2",
498                   "3": "slot3",
499                   "4": "slot4",
500                   "5": "slot5",
501                   "6": "slot6",
502                   "7": "slot7",
503               }),
504
505    # Check handling of default hash alg (sha256) with essiv
506    LUKSConfig("aes-256-cbc-essiv-auto-sha1",
507               "aes", 256, "cbc", "essiv", None, "sha1"),
508
509    # Check that a useless hash provided for 'plain64' iv gen
510    # is ignored and no error raised
511    LUKSConfig("aes-256-cbc-plain64-sha256-sha1",
512               "aes", 256, "cbc", "plain64", "sha256", "sha1"),
513
514]
515
516blacklist = [
517    # We don't have a cast-6 cipher impl for QEMU yet
518    "cast6-256-xts-plain64-sha1",
519    "cast6-128-xts-plain64-sha1",
520    "cast6-192-xts-plain64-sha1",
521
522    # GCrypt doesn't support Twofish with 192 bit key
523    "twofish-192-xts-plain64-sha1",
524]
525
526whitelist = []
527if "LUKS_CONFIG" in os.environ:
528    whitelist = os.environ["LUKS_CONFIG"].split(",")
529
530for config in configs:
531    if config.name in blacklist:
532        iotests.log("Skipping %s in blacklist" % config.name)
533        continue
534
535    if len(whitelist) > 0 and config.name not in whitelist:
536        iotests.log("Skipping %s not in whitelist" % config.name)
537        continue
538
539    test_once(config, qemu_img=False)
540
541    # XXX we should support setting passwords in a non-0
542    # key slot with 'qemu-img create' in future
543    (pw, slot) = config.first_password()
544    if slot == "0":
545        test_once(config, qemu_img=True)
546