Tests run with both SHA1 and SHA256 hashing.
"""
+import struct
import pytest
-import sys
import u_boot_utils as util
+import vboot_forge
+
+TESTDATA = [
+ ['sha1', '', None, False],
+ ['sha1', '', '-E -p 0x10000', False],
+ ['sha1', '-pss', None, False],
+ ['sha1', '-pss', '-E -p 0x10000', False],
+ ['sha256', '', None, False],
+ ['sha256', '', '-E -p 0x10000', False],
+ ['sha256', '-pss', None, False],
+ ['sha256', '-pss', '-E -p 0x10000', False],
+ ['sha256', '-pss', None, True],
+ ['sha256', '-pss', '-E -p 0x10000', True],
+]
@pytest.mark.boardspec('sandbox')
@pytest.mark.buildconfigspec('fit_signature')
@pytest.mark.requiredtool('fdtget')
@pytest.mark.requiredtool('fdtput')
@pytest.mark.requiredtool('openssl')
-def test_vboot(u_boot_console):
+@pytest.mark.parametrize("sha_algo,padding,sign_options,required", TESTDATA)
+def test_vboot(u_boot_console, sha_algo, padding, sign_options, required):
"""Test verified boot signing with mkimage and verification with 'bootm'.
This works using sandbox only as it needs to update the device tree used
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))
+ ['host 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))
+ assert 'sandbox: continuing, as we cannot run' in ''.join(output)
+ else:
+ assert('sandbox: continuing, as we cannot run'
+ not in ''.join(output))
def make_fit(its):
"""Make a new FIT from the .its source file.
util.run_and_log(cons, [mkimage, '-D', dtc_args, '-f',
'%s%s' % (datadir, its), fit])
- def sign_fit(sha_algo):
+ def sign_fit(sha_algo, options):
"""Sign the FIT
Signs the FIT and writes the signature into it. It also writes the
Args:
sha_algo: Either 'sha1' or 'sha256', to select the algorithm to
use.
+ options: Options to provide to mkimage.
"""
+ args = [mkimage, '-F', '-k', tmpdir, '-K', dtb, '-r', fit]
+ if options:
+ args += options.split(' ')
cons.log.action('%s: Sign images' % sha_algo)
- util.run_and_log(cons, [mkimage, '-F', '-k', tmpdir, '-K', dtb,
- '-r', fit])
+ util.run_and_log(cons, args)
- def test_with_algo(sha_algo):
+ def replace_fit_totalsize(size):
+ """Replace FIT header's totalsize with something greater.
+
+ The totalsize must be less than or equal to FIT_SIGNATURE_MAX_SIZE.
+ If the size is greater, the signature verification should return false.
+
+ Args:
+ size: The new totalsize of the header
+
+ Returns:
+ prev_size: The previous totalsize read from the header
+ """
+ total_size = 0
+ with open(fit, 'r+b') as handle:
+ handle.seek(4)
+ total_size = handle.read(4)
+ handle.seek(4)
+ handle.write(struct.pack(">I", size))
+ return struct.unpack(">I", total_size)[0]
+
+ def create_rsa_pair(name):
+ """Generate a new RSA key paid and certificate
+
+ Args:
+ name: Name of of the key (e.g. 'dev')
+ """
+ public_exponent = 65537
+ util.run_and_log(cons, 'openssl genpkey -algorithm RSA -out %s%s.key '
+ '-pkeyopt rsa_keygen_bits:2048 '
+ '-pkeyopt rsa_keygen_pubexp:%d' %
+ (tmpdir, name, public_exponent))
+
+ # Create a certificate containing the public key
+ util.run_and_log(cons, 'openssl req -batch -new -x509 -key %s%s.key '
+ '-out %s%s.crt' % (tmpdir, name, tmpdir, name))
+
+ def test_with_algo(sha_algo, padding, sign_options):
"""Test verified boot with the given hash algorithm.
This is the main part of the test code. The same procedure is followed
Args:
sha_algo: Either 'sha1' or 'sha256', to select the algorithm to
use.
+ padding: Either '' or '-pss', to select the padding to use for the
+ rsa signature algorithm.
+ sign_options: Options to mkimage when signing a fit image.
"""
# Compile our device tree files for kernel and U-Boot. These are
# regenerated here since mkimage will modify them (by adding a
# 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)
+ make_fit('sign-images-%s%s.its' % (sha_algo, padding))
run_bootm(sha_algo, 'unsigned images', 'dev-', True)
# Sign images with our dev keys
- sign_fit(sha_algo)
+ sign_fit(sha_algo, sign_options)
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)
+ make_fit('sign-configs-%s%s.its' % (sha_algo, padding))
run_bootm(sha_algo, 'unsigned config', '%s+ OK' % sha_algo, True)
# Sign images with our dev keys
- sign_fit(sha_algo)
+ sign_fit(sha_algo, sign_options)
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])
+ util.run_and_log(cons, [fit_check_sign, '-f', fit, '-k', dtb])
+
+ # Make sure that U-Boot checks that the config is in the list of hashed
+ # nodes. If it isn't, a security bypass is possible.
+ with open(fit, 'rb') as fd:
+ root, strblock = vboot_forge.read_fdt(fd)
+ root, strblock = vboot_forge.manipulate(root, strblock)
+ with open(fit, 'w+b') as fd:
+ vboot_forge.write_fdt(root, strblock, fd)
+ util.run_and_log_expect_exception(
+ cons, [fit_check_sign, '-f', fit, '-k', dtb],
+ 1, 'Failed to verify required signature')
+
+ run_bootm(sha_algo, 'forged config', 'Bad Data Hash', False)
+
+ # Create a new properly signed fit and replace header bytes
+ make_fit('sign-configs-%s%s.its' % (sha_algo, padding))
+ sign_fit(sha_algo, sign_options)
+ bcfg = u_boot_console.config.buildconfig
+ max_size = int(bcfg.get('config_fit_signature_max_size', 0x10000000), 0)
+ existing_size = replace_fit_totalsize(max_size + 1)
+ run_bootm(sha_algo, 'Signed config with bad hash', 'Bad Data Hash',
+ False)
+ cons.log.action('%s: Check overflowed FIT header totalsize' % sha_algo)
+
+ # Replace with existing header bytes
+ replace_fit_totalsize(existing_size)
+ run_bootm(sha_algo, 'signed config', 'dev+', True)
+ cons.log.action('%s: Check default FIT header totalsize' % sha_algo)
# Increment the first byte of the signature, which should cause failure
sig = util.run_and_log(cons, 'fdtget -t bx %s %s value' %
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)
+ 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')
+ util.run_and_log_expect_exception(
+ cons, [fit_check_sign, '-f', fit, '-k', dtb],
+ 1, 'Failed to verify required signature')
+
+ def test_required_key(sha_algo, padding, sign_options):
+ """Test verified boot with the given hash algorithm.
+
+ This function tests if U-Boot rejects an image when a required key isn't
+ used to sign a FIT.
+
+ Args:
+ sha_algo: Either 'sha1' or 'sha256', to select the algorithm to use
+ padding: Either '' or '-pss', to select the padding to use for the
+ rsa signature algorithm.
+ sign_options: Options to mkimage when signing a fit image.
+ """
+ # 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')
+
+ cons.log.action('%s: Test FIT with configs images' % sha_algo)
+
+ # Build the FIT with prod key (keys required) and sign it. This puts the
+ # signature into sandbox-u-boot.dtb, marked 'required'
+ make_fit('sign-configs-%s%s-prod.its' % (sha_algo, padding))
+ sign_fit(sha_algo, sign_options)
+
+ # Build the FIT with dev key (keys NOT required). This adds the
+ # signature into sandbox-u-boot.dtb, NOT marked 'required'.
+ make_fit('sign-configs-%s%s.its' % (sha_algo, padding))
+ sign_fit(sha_algo, sign_options)
+
+ # So now sandbox-u-boot.dtb two signatures, for the prod and dev keys.
+ # Only the prod key is set as 'required'. But FIT we just built has
+ # a dev signature only (sign_fit() overwrites the FIT).
+ # Try to boot the FIT with dev key. This FIT should not be accepted by
+ # U-Boot because the prod key is required.
+ run_bootm(sha_algo, 'required key', '', False)
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' %
- (tmpdir, public_exponent))
+ sig_node = '/configurations/conf-1/signature'
- # 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_rsa_pair('dev')
+ create_rsa_pair('prod')
# Create a number kernel image with zeroes
with open('%stest-kernel.bin' % tmpdir, 'w') as fd:
- fd.write(5000 * chr(0))
+ fd.write(500 * 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')
+ if required:
+ test_required_key(sha_algo, padding, sign_options)
+ else:
+ test_with_algo(sha_algo, padding, sign_options)
finally:
# Go back to the original U-Boot with the correct dtb.
cons.config.dtb = old_dtb
projects / oweals / u-boot.git / blobdiff