For the --generate operation, the --in <file> option is gone and there are
three new required options:
--vmlinuz <file> Embedded kernel image
--config <file> Embedded kernel command-line parameters
--bootloader <file> Embedded bootloader stub
This takes the specified kernel, extracts the 32-bit component, and combines
that with the configuration file (essentially just the kernel cmdline
string) and the bootstub image . The resulting blob is signed and ready to
put in a kernel partition.
There's also an optional --padding parameter, to specify how much extra
(unsigned) space to leave between the signature header and the kernel blob.
The default is 0x4000, which is about four times as much needed when using
the largest signature size we currently support.
Review URL: http://codereview.chromium.org/2283005
With this change, the kernel signature is a part of the preamble block (and therefore, used during preamble signature verification).
BUG=670
TEST=image verification tests still pass. corrected splicing test expectations (and it passes).
Review URL: http://codereview.chromium.org/2292001
This CL adds 2 things:
- Instead of having a kernel config, now we have a kernel preamble which contains some important parameters needed by the bootloader in the firmware to kernel hand-off. These parameters are verified using a separate preamble signature in addition to the kernel signature on actual kernel image data.
- Adds a new VerifyKernelHeader() API function which verifies the kernel verified boot header excluding the kernel data and also extracts parameters out of this header needed to verify the actual kernel image data (if deemed necessary). This allows for vboot header verification and data verification to be performed separately.
Review URL: http://codereview.chromium.org/2234003
This creates a new vboot_firmware subdirectory, and which contains the
entirety of the BIOS code. There shouldn't be anything in this directory
that is NOT required by the BIOS.
Review URL: http://codereview.chromium.org/2219004
The kernel_config is now stored as a 4K binary block instead of the kconfig_options structure that was being used before. Since the verified boot code doesn't care what kernel config options are (other than the length of the kernel image and for verifying them before the rest of kernel), it is ok to keep them as a blackbox.
This CL also changes the verified boot kernel layout - VBlock Data followed by Kernel Config followed by the Kernel Image. This will allow them to be stored separately, or as a concatenated block (for easy memory mapping during kernel load). This should ease the process of generating a layout for verified boot kernel images which is also compatible with legacy BIOSes that don't support this mechanism.
Finally, there is also a new firmware API function to determine the size of a kernel verified boot block, given a pointer to its beginning (for determining the offset to the kernel config and data).
Review URL: http://codereview.chromium.org/1732022
The firmware verification code no longer assumes that verification data and firmware data are contiguous and follow each other. Needed for EFI where the actual firmware must be stored in its own firmware volume.
BUG=1704
TEST=modified existing tests for the new API, and they still pass
Review URL: http://codereview.chromium.org/1578035
This should make it easier to switch off debug messages if needed.
TESTS=builds fine, autotest builds fine (using both arm/x86-generic)
Review URL: http://codereview.chromium.org/1607006
Refactor and restructure reference code into individual self-contain modules. I have revamped the way the code is structured to make it easy to determine which parts belong in the firmware and which are used by userland tools.
common/ - common utilities and stub functions (Firmware)
cryptolib/ - crypto library (Firmware)
misclibs/ - miscellaneous userland libraries (Userland)
sctips/ - Miscellaenous scripts (Userland)
tests/ - Tests (Userland)
vfirmware/ - Verified Firmware Implementation
vfirmware/firmware_image_fw.c (Firmware)
vfirmware/firmware_image.c (Userland)
vkernel/ - Verified Kernel Implementation
vkernel/kernel_image_fw.c (Firmware)
vkernel/kernel_image.c (Userland)
Review URL: http://codereview.chromium.org/1581005
Removing multiple top level includes - now padding.h, rsa.h and sha.h are used internally and cryptolib.h must be used instead for all modules that wish to use crypto functions.
I am trying to separate refactors involving code movement from one file to another, and the movement of files themselves into separate CLs so that it's clear what changed.
Review URL: http://codereview.chromium.org/1574005
This CL refactors verified boot firmware and kernel image functions into firmware and userland portions. Data Types and Functions that need to be a part of the final firmware implementation reside in files with "_fw" suffix - firmware_image_fw.{c|h} and kernel_image_fw.{c|h}.
Also some Makefile cleanups.
Review URL: http://codereview.chromium.org/1599001
This CL fixes some functions to use uint64_t that I missed the first time around. It ended up requiring some minor changes to how some of the helper functions work (StatefulMemcpy*()).
Also adds new tests to make sure that reference code can verify/process big firmware and kernel images.
BUG=670
TEST=Adds some new, old ones still pass.
Review URL: http://codereview.chromium.org/1519008
BUG=670
TESTS=Adds new tests which verify this doesn't occur anymore. Existing tests still pass.
The existing code computes and verifies signatures on firmware/kernel data and firmware/kernel versions separately. This causes a image splicing bug where it is possible to combine together a version signature from a valid new firmware with firmware data and signature from an older version. The same problem exists with kernel verification.
This CL fixes this by changing the firmware/kernel signatures to also include the version information.
For the Firmware, there's a separate signature on the preamble (which contains the version) but the firmware signature now also includes this preamble in addition to the firmware data.
For the Kernel, there's a separate signature on the kernel config/options (wich also contains the version), but the kernel signature now also includes these config/options in addition to the kernel data.
Review URL: http://codereview.chromium.org/1430001
Also removes the dev_mode flag from Firmware Image verification as key signature for the firmware should be checked whether or not dev mode is enabled.
BUG=670
TEST=All tests still pass.
Merge remote branch 'refs/remotes/origin/master' into fixtests
Fix tests, remove dev mode. Move common code.
Review URL: http://codereview.chromium.org/1280002
This CL adds a new function VerifyFirmwareDriver_f() means to be a part of the RO firmware which determine which copy of the firmware to boot from. It is meant to ensure that a particular firmware is only booted if 1) it verifies successfully, 2) its version is newer or equal to current stored version. In addition, the driver function also updates the stored version if needed.
Currently I am using the TLCL API with stub calls, (in fact, most of the TPM interaction is done in rollback_index.c which implements the actual version query/update API) used by the firmware.
Review URL: http://codereview.chromium.org/1241002
Refactor duplicate code for the firmware image benchmark. Also fixes some functions that manipulate kernel blobs (use uint64_t instead if int).
Review URL: http://codereview.chromium.org/1079009
The benchmark calculates the time taken to verify a firmware image of various sizes for various combinations of signature algorithm. This is meant to be called through autotest.
Review URL: http://codereview.chromium.org/1127007
This spews out useful information about a verified boot firmware/kernel image. Also adds a helper function to calculate header checksum. That code was being duplicated at multiple places.
Review URL: http://codereview.chromium.org/1088001
The driver programs are useful in quick and dirty fuzz testing of the verification code with blind smartfuzzers like Bunny (http://code.google.com/p/bunny-the-fuzzer/).
Also fixes a bug with image generation in kernel_utility.
Tests: All existing tests still pass. VerifyKernel() and VerifyFirmware() can successfully verify images generated by {firmware|kernel}_utility.
Review URL: http://codereview.chromium.org/975007
Fix memory leaks found using Valgrind, adds sanity checking to RSAPublicKey parsing code to prevent crazy behavior.
Review URL: http://codereview.chromium.org/858008
I previously refactored some of the signature generation code to directly use the OpenSSL library instead of invoking the "openssl" command line utility. The signature_digest command line utility got lost in the process. This restores the utility which in turn fixes the RSA verification test.
Review URL: http://codereview.chromium.org/669040
This CL does the following:
1) It adds a SignatureBuf function which uses the OpenSSL library to generate RSA signature. This is more robust than the previous way of invoking the command line "openssl" utility and capturing its output. No more unnecessary temporary files for signature operations.
2) It adds functions that allow direct manipulation of binary verified Firmware and Kernel Image blobs in memory.
3) It changes the structure field members for FirmwareImage to make it consistent with KernelImage. Now it's clearer which key is used when.
4) Minor bug fixes and slightly improved API for dealing verified boot firmware and kernel images.
5) Renames the RSA_verify function to prevent conflicts with OpenSSL since it's linked into the firmware utility binary.
Review URL: http://codereview.chromium.org/661353
BUG=670
TEST=Adds kernel_image_test which tests the new functions.
The kernel image verification pretty much exactly mirror the already existing firmware image verification functions except with a few different/additional fields in a signed kernel image. The firmware signing key is the root key equivalent for kernel images.
This CL also moves the image verification tests to a different script. There's some additional cleanup of the code that I will be submitting separately after this and another pending patches get LGTMed and land.
Review URL: http://codereview.chromium.org/660161
This is a first cut at what I envision as a utility we can use to manage our firmware/kernel signing needs. Currently, it implements firmware signing (given a binary image, create a verified boot header) and verification (given a verified boot image, verify it using the given public root key).
This CL also fixes the ReadFirmwareImage function from firmware_image to make it more consistent and fixes some bugs.
Review URL: http://codereview.chromium.org/652216
This test checks that signatures with improper padding do not get accepted by the RSA signature verification implementation.
Review URL: http://codereview.chromium.org/661038
The old VerifyFirmware function (now called VerifyFirmwareImage) works on the FirmwareImage structure. This CL adds a verification function which can be used directly on packed binary verified boot firmware blobs. This function can be used as the reference implementation for verified boot in firmware. In addition, all functions that work on FirmwareImage structure have been renames to distinguish them from those which work on binary firmware blobs.
In addition, this adds some new crypto utility functions and refactors old ones.
BUG=670
TEST=Added tests for the new function and they pass.
Review URL: http://codereview.chromium.org/650105
In addtion, add test cases and a script to generate them for benchmarking. Also fixes a path problem with the run_rsa_tests.sh script.
Review URL: http://codereview.chromium.org/626011
Also rename and modify run_tests.sh to only run the RSA verification tests. The SHA message digest tests must now be invoked separately.
Review URL: http://codereview.chromium.org/596080