[RFC PATCH] binman: bintool: etype: Add support for ti-secure entry
Andrew Davis
afd at ti.com
Wed Mar 1 18:11:59 CET 2023
On 2/28/23 9:10 AM, Simon Glass wrote:
> Hi Neha,
>
> On Tue, 28 Feb 2023 at 02:50, Neha Malcom Francis <n-francis at ti.com> wrote:
>>
>> Hi Simon,
>>
>> On 28/02/23 06:05, Simon Glass wrote:
>>> Hi Neha,
>>>
>>> On Fri, 24 Feb 2023 at 05:03, Neha Malcom Francis <n-francis at ti.com> wrote:
>>>>
>>>> core-secdev-k3 is the TI security development package provided for K3
>>>> platform devices. This tool helps sign bootloader images with the x509
>>>> ceritificate header.
>>>>
>>>> Signed-off-by: Neha Malcom Francis <n-francis at ti.com>
>>>> ---
>>>> This patch depends on https://patchwork.ozlabs.org/project/uboot/patch/20230224115101.563729-1-n-francis@ti.com/
>>>> and on ongoing development in https://git.ti.com/cgit/security-development-tools/core-secdev-k3
>>>>
>>>> tools/binman/btool/tisecuretool.py | 72 +++++++++++
>>>> tools/binman/etype/ti_secure.py | 114 ++++++++++++++++++
>>>> tools/binman/ftest.py | 36 ++++++
>>>> tools/binman/test/278_ti_secure_rom.dts | 11 ++
>>>> tools/binman/test/279_ti_secure.dts | 11 ++
>>>> .../binman/test/280_ti_secure_nofilename.dts | 10 ++
>>>> tools/binman/test/281_ti_secure_combined.dts | 12 ++
>>>> 7 files changed, 266 insertions(+)
>>>> create mode 100644 tools/binman/btool/tisecuretool.py
>>>> create mode 100644 tools/binman/etype/ti_secure.py
>>>> create mode 100644 tools/binman/test/278_ti_secure_rom.dts
>>>> create mode 100644 tools/binman/test/279_ti_secure.dts
>>>> create mode 100644 tools/binman/test/280_ti_secure_nofilename.dts
>>>> create mode 100644 tools/binman/test/281_ti_secure_combined.dts
>>>
>>> Now that I see what you are doing, this it not quite the right way.
>>>
>>> See this hack-up of how you can call the openssl thing. Basically you
>>> should not have a shell script in the way, but instead make your
>>> bintool do it.
>>>
>>> https://github.com/sjg20/u-boot/commit/03c0d74f81106570b18d8e4fe7a3355bfeb0d5da#r100378804
>>>
>>> I suppose we can have an openssl bintool that others build on top of?
>>>
>>> Regards,
>>> Simon
>>>
>>>
>>
>> That is possible, maybe ti-secure extends from x509_cert etype so as to
>> support the TI specific certificate extensions. I'll start working on this.
>>
>> However the patches I've sent support external production flow where
>> signing need not necessarily be carried out from U-Boot. An external
>> repo that acts as what is core-secdev-k3 here, would be the repo
>> responsible for signing.
>>
>> Could we find a way to combine both so as to support production flow
>> mandating an external agency, as well as a completely within U-Boot flow
>> using bintool? i.e. we modify ti-secure etype to be able to support both
>> external git repo/executable script signing as well as default signing
>> using openssl bintool.
>
> Yes that seems important.
>
> One option is to have binman emit some instructions on how to sign the
> image, perhaps a simple data format similar to an fdtmap, with a basic
> shell script plus whatever the etype provides. Then the signer can
> follow the instructions or run the script.
>
> Another option is to run binman on the signer and have it do the
> signing. Would that work?
>
I'd like to keep the dependencies needed on the signing server as
minimal as possible. We do require the "u-boot-tools" package on
the key servers if folks want to re-package signed FIT images, so
if binman could be reasonably packaged in that package someday
it could be an option.
For now, if binman could generate the x509 file and leave it with the
other boot artifacts then if one needs to re-sign with real keys they
will only need to have openssl sign that cert and append to the image
on the key server, that is simple enough document.
The more difficult part is in re-packaging these signed images.
Our security tools already have a tool to disasemble a FIT image,
sign the components, then re-assemble it[0]. This would work for
u-boot.img and the kernel FIT images, but we would need something
new for re-assembling boot3.bin and tispl.bin. The first boot files
(boot3.bin) is also more complex that simple FIT images in that it
has several variations in format and content based on device family
and type.
The ideal case would be we do not need to pull in the TI security tools
package at all and we could drop this patch. The tools would then only be
needed by folks wanting to sign their images using an external key
server.
If we could have binman learn how to generate/template x509 certs and
have it sign them with openssl, plus add the TI dummy[1] and degenerate[2]
keys to the u-boot source repo, then we would not need TI security
tools any more here.
This might be a longer term goal though, and I think we are already
trying to do too much all at once as is. Perhaps we could take
this current solution posted here with the intent to remove it in
the near future. Thoughts?
Andrew
[0] https://git.ti.com/cgit/security-development-tools/core-secdev-k3/tree/scripts/fit-image-secure.sh
[1] https://git.ti.com/cgit/security-development-tools/core-secdev-k3/tree/keys/custMpk.pem
[2] https://git.ti.com/cgit/security-development-tools/core-secdev-k3/tree/keys/ti-degenerate-key.pem
> Regards,
> Simon
>
>
>>
>>>>
>>>> diff --git a/tools/binman/btool/tisecuretool.py b/tools/binman/btool/tisecuretool.py
>>>> new file mode 100644
>>>> index 0000000000..5102bb1f7d
>>>> --- /dev/null
>>>> +++ b/tools/binman/btool/tisecuretool.py
>>>> @@ -0,0 +1,72 @@
>>>> +# SPDX-License-Identifier: GPL-2.0+
>>>> +# Copyright (c) 2022 Texas Instruments Incorporated - https://www.ti.com/
>>>> +# Written by Neha Malcom Francis <n-francis at ti.com>
>>>> +#
>>>> +"""Bintool implementation for TI security development tools
>>>> +
>>>> +tisecuretool helps add x509 certification for bootloader images for K3 platform devices
>>>> +
>>>> +Source code:
>>>> +https://git.ti.com/cgit/security-development-tools/core-secdev-k3/"""
>>>> +
>>>> +import os
>>>> +
>>>> +from binman import bintool
>>>> +from patman import tout
>>>> +from patman import tools
>>>> +
>>>> +class Bintooltisecuretool(bintool.Bintool):
>>>> + """Signing tool for TI bootloaders"""
>>>> + name = 'tisecuretool'
>>>> + def __init__(self, name):
>>>> + super().__init__(name, 'TI secure tool')
>>>> +
>>>> + def sign_binary_secure(self, fname, out_fname):
>>>> + """Create a signed binary
>>>> +
>>>> + Args:
>>>> + fname (str): Filename to sign
>>>> + out_fname (str): Output filename
>>>> +
>>>> + Returns:
>>>> + str: Tool output
>>>> + or None
>>>> + """
>>>> + tool_path = self.get_path()
>>>> + script_path = os.path.join(tool_path, 'scripts/secure-binary-image.sh')
>>>> + args = [
>>>> + 'sh',
>>>> + script_path,
>>>> + fname,
>>>> + out_fname
>>>> + ]
>>>> + output = self.run_cmd(*args, add_name=False)
>>>> + return output
>>>> +
>>>> + def sign_binary_rom(self, args):
>>>> + """Create a signed binary that is booted by ROM
>>>> +
>>>> + Args:
>>>> + fname (str): Filename to sign
>>>> + out_fname (str): Output filename"""
>>>> + tool_path = self.get_path()
>>>> + script_path = os.path.join(tool_path, 'scripts/secure-rom-boot-image.sh')
>>>> + #args.insert(0, script_path)
>>>> + args.insert(0, script_path)
>>>> + output = self.run_cmd(*args, add_name=False)
>>>> + return output
>>>> +
>>>> + def fetch(self, method):
>>>> + """Fetch handler for TI secure tool
>>>> +
>>>> + This builds the tool from source
>>>> +
>>>> + Returns:
>>>> + True if the file was fetched, None if a method other than FETCH_SOURCE
>>>> + was requested
>>>> + """
>>>> + if method != bintool.FETCH_SOURCE:
>>>> + return None
>>>> + result = self.fetch_from_git(
>>>> + 'git://git.ti.com/security-development-tools/core-secdev-k3.git', 'tisecuretool')
>>>> + return result
>>>> diff --git a/tools/binman/etype/ti_secure.py b/tools/binman/etype/ti_secure.py
>>>> new file mode 100644
>>>> index 0000000000..26f81ff8e8
>>>> --- /dev/null
>>>> +++ b/tools/binman/etype/ti_secure.py
>>>> @@ -0,0 +1,114 @@
>>>> +# SPDX-License-Identifier: GPL-2.0+
>>>> +# Copyright (c) 2022 Texas Instruments Incorporated - https://www.ti.com/
>>>> +# Written by Neha Malcom Francis <n-francis at ti.com>
>>>> +#
>>>> +# Entry-type module for signed binaries for TI K3 platform
>>>> +#
>>>> +
>>>> +from binman.etype.blob import Entry_blob
>>>> +from binman import bintool
>>>> +
>>>> +from dtoc import fdt_util
>>>> +from patman import terminal
>>>> +from patman import tools
>>>> +from patman import tout
>>>> +
>>>> +class Entry_ti_secure(Entry_blob):
>>>> + """An entry which contains a signed x509 binary for signing TI
>>>> + General Purpose as well as High-Security devices.
>>>> +
>>>> + Properties / Entry arguments:
>>>> + - filename: filename of binary file to be secured
>>>> +
>>>> + Output files:
>>>> + - filename_x509 - output file generated by secure x509 signing script (which
>>>> + used as entry contents)
>>>> + """
>>>> + def __init__(self, section, etype, node):
>>>> + super().__init__(section, etype, node)
>>>> + self.filename = fdt_util.GetString(self._node, 'filename')
>>>> + self.core = fdt_util.GetString(self._node, 'core', 'secure')
>>>> + self.load_addr = fdt_util.GetInt(self._node, 'load', 0x41c00000)
>>>> + self.sw_rev = fdt_util.GetInt(self._node, 'sw-rev', 1)
>>>> + self.sysfw_cert = fdt_util.GetBool(self._node, 'sysfw-cert', False)
>>>> + self.secure = fdt_util.GetBool(self._node, 'secure', False)
>>>> + self.combined = fdt_util.GetBool(self._node, 'combined', False)
>>>> + self.split_dm = fdt_util.GetBool(self._node, 'split-dm', False)
>>>> + self.sysfw_filename = fdt_util.GetString(self._node, 'sysfw-filename')
>>>> + self.sysfw_load_addr = fdt_util.GetInt(self._node, 'sysfw-load', 0x40000)
>>>> + self.sysfw_data_filename = fdt_util.GetString(self._node, 'sysfw-data-filename')
>>>> + self.sysfw_data_load_addr = fdt_util.GetInt(self._node, 'sysfw-data-load', 0x7f000)
>>>> + self.sysfw_inner_cert = fdt_util.GetString(self._node, 'sysfw-inner-cert', "")
>>>> + self.dm_data_filename = fdt_util.GetString(self._node, 'dm-data-filename')
>>>> + self.dm_data_load_addr = fdt_util.GetInt(self._node, 'dm-data-load', 0x41c80000)
>>>> + self.sysfw_inner_cert_filename = fdt_util.GetString(self._node, 'sysfw-inner-cert-filename')
>>>> + self.toolpresent = False
>>>> + if not self.filename:
>>>> + self.Raise("ti_secure must have a 'filename' property")
>>>> +
>>>> + def _SignBinarySecure(self):
>>>> + infilename = self.filename
>>>> + outfilename = infilename + '_signed'
>>>> +
>>>> + data = self.tisecuretool.sign_binary_secure(infilename, outfilename)
>>>> +
>>>> + if data is None:
>>>> + # Bintool is missing, create a zeroed binary
>>>> + self.record_missing_bintool(self.tisecuretool)
>>>> + return tools.get_bytes(0, 1024)
>>>> +
>>>> + return tools.read_file(outfilename)
>>>> +
>>>> + def _SignBinaryROM(self):
>>>> + input_fname = self.filename
>>>> + output_fname = input_fname + "_x509"
>>>> + if self.combined:
>>>> + args = [
>>>> + '-b', input_fname,
>>>> + '-l', hex(self.load_addr),
>>>> + '-s', self.sysfw_filename,
>>>> + '-m', hex(self.sysfw_load_addr),
>>>> + '-a', self.sysfw_inner_cert,
>>>> + '-d', self.sysfw_data_filename,
>>>> + '-n', hex(self.sysfw_data_load_addr),
>>>> + '-r', str(self.sw_rev),
>>>> + '-o', output_fname,
>>>> + ]
>>>> + if self.split_dm:
>>>> + args.extend(['-t', self.dm_data_filename, '-y', hex(self.dm_data_load_addr)])
>>>> + else:
>>>> + args = [
>>>> + '-a', self.core,
>>>> + '-b', input_fname,
>>>> + '-o', output_fname,
>>>> + '-l', hex(self.load_addr),
>>>> + '-r', str(self.sw_rev),
>>>> +
>>>> + ]
>>>> + if self.sysfw_cert == True:
>>>> + args.insert(0, '-u')
>>>> +
>>>> + out = self.tisecuretool.sign_binary_rom(args)
>>>> +
>>>> + if out is None:
>>>> + # Bintool is missing, create a zeroed binary
>>>> + self.record_missing_bintool(self.tisecuretool)
>>>> + return tools.get_bytes(0, 1024)
>>>> +
>>>> + return tools.read_file(output_fname)
>>>> +
>>>> + def ProcessContents(self):
>>>> + if self.secure:
>>>> + data = self._SignBinarySecure()
>>>> + else:
>>>> + data = self._SignBinaryROM()
>>>> + return self.ProcessContentsUpdate(data)
>>>> +
>>>> + def AddBintools(self, btools):
>>>> + #super().AddBintools(btools)
>>>> + col = terminal.Color()
>>>> + self.tisecuretool = self.AddBintool(btools, 'tisecuretool')
>>>> + out = self.tisecuretool.fetch_tool(bintool.FETCH_SOURCE, col, True)
>>>> + if out == bintool.FAIL:
>>>> + # Bintool is missing, record missing
>>>> + self.record_missing_bintool(self.tisecuretool)
>>>> \ No newline at end of file
>>>> diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
>>>> index bf902341c5..72cce0ef02 100644
>>>> --- a/tools/binman/ftest.py
>>>> +++ b/tools/binman/ftest.py
>>>> @@ -97,6 +97,7 @@ PRE_LOAD_MAGIC = b'UBSH'
>>>> PRE_LOAD_VERSION = 0x11223344.to_bytes(4, 'big')
>>>> PRE_LOAD_HDR_SIZE = 0x00001000.to_bytes(4, 'big')
>>>> TI_BOARD_CONFIG_DATA = b'\x00\x01'
>>>> +TIX509DATA = b'letsgo'
>>>>
>>>> # Subdirectory of the input dir to use to put test FDTs
>>>> TEST_FDT_SUBDIR = 'fdts'
>>>> @@ -206,6 +207,7 @@ class TestFunctional(unittest.TestCase):
>>>> TestFunctional._MakeInputFile('bl2u.bin', ATF_BL2U_DATA)
>>>> TestFunctional._MakeInputFile('fw_dynamic.bin', OPENSBI_DATA)
>>>> TestFunctional._MakeInputFile('scp.bin', SCP_DATA)
>>>> + TestFunctional._MakeInputFile('to_sign.bin', TIX509DATA)
>>>>
>>>> # Add a few .dtb files for testing
>>>> TestFunctional._MakeInputFile('%s/test-fdt1.dtb' % TEST_FDT_SUBDIR,
>>>> @@ -6398,5 +6400,39 @@ fdt fdtmap Extract the devicetree blob from the fdtmap
>>>> configlen_noheader = TI_BOARD_CONFIG_DATA*4
>>>> self.assertGreater(data, configlen_noheader)
>>>>
>>>> + def testTISecureROMImageMissingTool(self):
>>>> + """Test that a TI secure signed ROM booted image can be generated although tisecuretool is missing"""
>>>> + with test_util.capture_sys_output() as (_, stderr):
>>>> + data = self._DoTestFile('278_ti_secure_rom.dts',
>>>> + force_missing_bintools='tisecuretool')
>>>> + err = stderr.getvalue()
>>>> + self.assertRegex(err,
>>>> + "Image 'image'.*missing bintools.*: tisecuretool")
>>>> +
>>>> + def testTISecureImageMissingTool(self):
>>>> + """Test that a TI secure signed image can be generated although tisecuretool is missing"""
>>>> + with test_util.capture_sys_output() as (_, stderr):
>>>> + data = self._DoTestFile('279_ti_secure.dts',
>>>> + force_missing_bintools='tisecuretool')
>>>> + err = stderr.getvalue()
>>>> + self.assertRegex(err,
>>>> + "Image 'image'.*missing bintools.*: tisecuretool")
>>>> +
>>>> + def testTISecureNoFilename(self):
>>>> + """Test that a missing 'filename' property is detected"""
>>>> + with self.assertRaises(ValueError) as e:
>>>> + self._DoTestFile('280_ti_secure_nofilename.dts')
>>>> + self.assertIn("ti_secure must have a 'filename' property",
>>>> + str(e.exception))
>>>> +
>>>> + def testTISecureImageCombinedMissingTool(self):
>>>> + """Test that a TI secure signed image can be generated although tisecuretool is missing"""
>>>> + with test_util.capture_sys_output() as (_, stderr):
>>>> + data = self._DoTestFile('281_ti_secure_combined.dts',
>>>> + force_missing_bintools='tisecuretool')
>>>> + err = stderr.getvalue()
>>>> + self.assertRegex(err,
>>>> + "Image 'image'.*missing bintools.*: tisecuretool")
>>>> +
>>>> if __name__ == "__main__":
>>>> unittest.main()
>>>> diff --git a/tools/binman/test/278_ti_secure_rom.dts b/tools/binman/test/278_ti_secure_rom.dts
>>>> new file mode 100644
>>>> index 0000000000..67a6a9de8d
>>>> --- /dev/null
>>>> +++ b/tools/binman/test/278_ti_secure_rom.dts
>>>> @@ -0,0 +1,11 @@
>>>> +// SPDX-License-Identifier: GPL-2.0+
>>>> +/dts-v1/;
>>>> +
>>>> +/ {
>>>> + binman {
>>>> + ti-secure {
>>>> + filename = "to_sign.bin";
>>>> + sysfw-cert;
>>>> + };
>>>> + };
>>>> +};
>>>> diff --git a/tools/binman/test/279_ti_secure.dts b/tools/binman/test/279_ti_secure.dts
>>>> new file mode 100644
>>>> index 0000000000..0e60984013
>>>> --- /dev/null
>>>> +++ b/tools/binman/test/279_ti_secure.dts
>>>> @@ -0,0 +1,11 @@
>>>> +// SPDX-License-Identifier: GPL-2.0+
>>>> +/dts-v1/;
>>>> +
>>>> +/ {
>>>> + binman {
>>>> + ti-secure {
>>>> + filename = "to_sign.bin";
>>>> + secure;
>>>> + };
>>>> + };
>>>> +};
>>>> diff --git a/tools/binman/test/280_ti_secure_nofilename.dts b/tools/binman/test/280_ti_secure_nofilename.dts
>>>> new file mode 100644
>>>> index 0000000000..928a50a499
>>>> --- /dev/null
>>>> +++ b/tools/binman/test/280_ti_secure_nofilename.dts
>>>> @@ -0,0 +1,10 @@
>>>> +// SPDX-License-Identifier: GPL-2.0+
>>>> +/dts-v1/;
>>>> +
>>>> +/ {
>>>> + binman {
>>>> + ti-secure {
>>>> + secure;
>>>> + };
>>>> + };
>>>> +};
>>>> diff --git a/tools/binman/test/281_ti_secure_combined.dts b/tools/binman/test/281_ti_secure_combined.dts
>>>> new file mode 100644
>>>> index 0000000000..aadb5a4306
>>>> --- /dev/null
>>>> +++ b/tools/binman/test/281_ti_secure_combined.dts
>>>> @@ -0,0 +1,12 @@
>>>> +// SPDX-License-Identifier: GPL-2.0+
>>>> +/dts-v1/;
>>>> +
>>>> +/ {
>>>> + binman {
>>>> + ti-secure {
>>>> + filename = "to_sign.bin";
>>>> + combined;
>>>> + split-dm;
>>>> + };
>>>> + };
>>>> +};
>>>> --
>>>> 2.34.1
>>>>
>>
>> --
>> Thanking You
>> Neha Malcom Francis
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