u-boot/test/py/tests/test_vboot.py
Tom Rini de4be9ec17 test/py/tests/test_vboot.py: Add check that we boot the image
Make sure that when we're telling bootm to boot an image, and we expect
the image to boot we get the output from sandbox that we attempted to
run Linux and that U-Boot completed its job.

Cc: Simon Glass <sjg@chromium.org>
Cc: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
2016-09-22 11:34:58 -04:00

198 lines
7.1 KiB
Python

# Copyright (c) 2016, Google Inc.
#
# SPDX-License-Identifier: GPL-2.0+
#
# U-Boot Verified Boot Test
"""
This tests verified boot in the following ways:
For image verification:
- Create FIT (unsigned) with mkimage
- Check that verification shows that no keys are verified
- Sign image
- Check that verification shows that a key is now verified
For configuration verification:
- Corrupt signature and check for failure
- Create FIT (with unsigned configuration) with mkimage
- Check that image verification works
- Sign the FIT and mark the key as 'required' for verification
- Check that image verification works
- Corrupt the signature
- Check that image verification no-longer works
Tests run with both SHA1 and SHA256 hashing.
"""
import pytest
import sys
import u_boot_utils as util
@pytest.mark.boardspec('sandbox')
@pytest.mark.buildconfigspec('fit_signature')
def test_vboot(u_boot_console):
"""Test verified boot signing with mkimage and verification with 'bootm'.
This works using sandbox only as it needs to update the device tree used
by U-Boot to hold public keys from the signing process.
The SHA1 and SHA256 tests are combined into a single test since the
key-generation process is quite slow and we want to avoid doing it twice.
"""
def dtc(dts):
"""Run the device tree compiler to compile a .dts file
The output file will be the same as the input file but with a .dtb
extension.
Args:
dts: Device tree file to compile.
"""
dtb = dts.replace('.dts', '.dtb')
util.run_and_log(cons, 'dtc %s %s%s -O dtb '
'-o %s%s' % (dtc_args, datadir, dts, tmpdir, dtb))
def run_bootm(sha_algo, test_type, expect_string, boots):
"""Run a 'bootm' command U-Boot.
This always starts a fresh U-Boot instance since the device tree may
contain a new public key.
Args:
test_type: A string identifying the test type.
expect_string: A string which is expected in the output.
sha_algo: Either 'sha1' or 'sha256', to select the algorithm to
use.
boots: A boolean that is True if Linux should boot and False if
we are expected to not boot
"""
cons.restart_uboot()
with cons.log.section('Verified boot %s %s' % (sha_algo, test_type)):
output = cons.run_command_list(
['sb load hostfs - 100 %stest.fit' % tmpdir,
'fdt addr 100',
'bootm 100'])
assert(expect_string in ''.join(output))
if boots:
assert('sandbox: continuing, as we cannot run' in ''.join(output))
def make_fit(its):
"""Make a new FIT from the .its source file.
This runs 'mkimage -f' to create a new FIT.
Args:
its: Filename containing .its source.
"""
util.run_and_log(cons, [mkimage, '-D', dtc_args, '-f',
'%s%s' % (datadir, its), fit])
def sign_fit(sha_algo):
"""Sign the FIT
Signs the FIT and writes the signature into it. It also writes the
public key into the dtb.
Args:
sha_algo: Either 'sha1' or 'sha256', to select the algorithm to
use.
"""
cons.log.action('%s: Sign images' % sha_algo)
util.run_and_log(cons, [mkimage, '-F', '-k', tmpdir, '-K', dtb,
'-r', fit])
def test_with_algo(sha_algo):
"""Test verified boot with the given hash algorithm.
This is the main part of the test code. The same procedure is followed
for both hashing algorithms.
Args:
sha_algo: Either 'sha1' or 'sha256', to select the algorithm to
use.
"""
# Compile our device tree files for kernel and U-Boot. These are
# regenerated here since mkimage will modify them (by adding a
# public key) below.
dtc('sandbox-kernel.dts')
dtc('sandbox-u-boot.dts')
# Build the FIT, but don't sign anything yet
cons.log.action('%s: Test FIT with signed images' % sha_algo)
make_fit('sign-images-%s.its' % sha_algo)
run_bootm(sha_algo, 'unsigned images', 'dev-', True)
# Sign images with our dev keys
sign_fit(sha_algo)
run_bootm(sha_algo, 'signed images', 'dev+', True)
# Create a fresh .dtb without the public keys
dtc('sandbox-u-boot.dts')
cons.log.action('%s: Test FIT with signed configuration' % sha_algo)
make_fit('sign-configs-%s.its' % sha_algo)
run_bootm(sha_algo, 'unsigned config', '%s+ OK' % sha_algo, True)
# Sign images with our dev keys
sign_fit(sha_algo)
run_bootm(sha_algo, 'signed config', 'dev+', True)
cons.log.action('%s: Check signed config on the host' % sha_algo)
util.run_and_log(cons, [fit_check_sign, '-f', fit, '-k', tmpdir,
'-k', dtb])
# Increment the first byte of the signature, which should cause failure
sig = util.run_and_log(cons, 'fdtget -t bx %s %s value' %
(fit, sig_node))
byte_list = sig.split()
byte = int(byte_list[0], 16)
byte_list[0] = '%x' % (byte + 1)
sig = ' '.join(byte_list)
util.run_and_log(cons, 'fdtput -t bx %s %s value %s' %
(fit, sig_node, sig))
run_bootm(sha_algo, 'Signed config with bad hash', 'Bad Data Hash', False)
cons.log.action('%s: Check bad config on the host' % sha_algo)
util.run_and_log_expect_exception(cons, [fit_check_sign, '-f', fit,
'-k', dtb], 1, 'Failed to verify required signature')
cons = u_boot_console
tmpdir = cons.config.result_dir + '/'
tmp = tmpdir + 'vboot.tmp'
datadir = cons.config.source_dir + '/test/py/tests/vboot/'
fit = '%stest.fit' % tmpdir
mkimage = cons.config.build_dir + '/tools/mkimage'
fit_check_sign = cons.config.build_dir + '/tools/fit_check_sign'
dtc_args = '-I dts -O dtb -i %s' % tmpdir
dtb = '%ssandbox-u-boot.dtb' % tmpdir
sig_node = '/configurations/conf@1/signature@1'
# Create an RSA key pair
public_exponent = 65537
util.run_and_log(cons, 'openssl genpkey -algorithm RSA -out %sdev.key '
'-pkeyopt rsa_keygen_bits:2048 '
'-pkeyopt rsa_keygen_pubexp:%d '
'2>/dev/null' % (tmpdir, public_exponent))
# Create a certificate containing the public key
util.run_and_log(cons, 'openssl req -batch -new -x509 -key %sdev.key -out '
'%sdev.crt' % (tmpdir, tmpdir))
# Create a number kernel image with zeroes
with open('%stest-kernel.bin' % tmpdir, 'w') as fd:
fd.write(5000 * chr(0))
try:
# We need to use our own device tree file. Remember to restore it
# afterwards.
old_dtb = cons.config.dtb
cons.config.dtb = dtb
test_with_algo('sha1')
test_with_algo('sha256')
finally:
# Go back to the original U-Boot with the correct dtb.
cons.config.dtb = old_dtb
cons.restart_uboot()