roll: third_party/pigweed/src 4b9814b..b51ab5d (30 commits)

b51ab5d:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302857 roll: luci
94d6848:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302892 roll: fuchsia-infra-bazel-rules 59a6e83..4da15df (30 commits)
0eb18bb:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302872 roll: ninja
b09f9a1:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301738 docs: New workorder concept for AI development
f427d46:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301461 pw_string: Build and test the known size example
2670f90:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301532 pw_ide: Support fish shell in compile commands interceptor
0d991ea:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302056 pw_channel: PacketChannel implementation for testing
279761a:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301693 pw_containers: Deque emplace and insert functions
3fd1432:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302533 pw_toolchain: Disable -Wmaybe-uninitialized on Windows GCC builds
cc167eb:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301745 pw_rpc_transport: Require that trackers be instantiated
3717305:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301751 pw_channel: Handle staging multiple; write_waker() function
3ba5797:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302392 pw_bluetooth_sapphire: Reorganize StopAdvertising calls
460a420:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302276 pw_allocator: Fix missing comma in Android.bp
b764318:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/295312 pw_bluetooth_sapphire: Enable autosniff
1e8f5b9:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/295052 pw_bluetooth_sapphire: Set default link policy setting
9ec6495:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302032 Reland "pw_protobuf: Only generate `kMaxEncodedSizeBytes` in constrained structs"
88f6134:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302054 targets/rp2040: Cover RP2350 in upstream guide
54cc280:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/302292 pw_presubmit: Move test data to tests
3ef922d:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301712 pw_allocator: Add control_block to the Android build
e20ebe4:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301935 pw_rpc_transport: Format Android.bp file
74227a3:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301774 pw_cli: Add characters needing escaping to push
8b77226:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301832 pw_bluetooth_proxy: Rename comms2.5 directory to comms2
45c92e6:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301456 pw_kernel: Add initial pw_atomic traits
d66e7fe:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/300712 pw_kernel: Switch to stable toolchain
1cde803:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301692 pw_containers: Remove redundant DequeIterator checks
3e24cb6:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301773 pw_containers: Prevent construction of generic-capacity async deques
64adaf5:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301733 roll: luci
61cc0d2:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301535 roll: ninja
526f927:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301732 roll: fuchsia-infra-bazel-rules 45bf47c..59a6e83 (54 commits)
4781a70:https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/301224 pw_ide: Disable writing json5 settings.json to avoid corruption

Rolled-Repo: https://pigweed.googlesource.com/pigweed/pigweed
Rolled-Commits: 4b9814b2fe75be..b51ab5d2632df0
Roll-Count: 1
Roller-URL: https://cr-buildbucket.appspot.com/build/8710047156475139425
GitWatcher: ignore
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: Ic6b0a8ae23d7a71ab513dae634fbf7f2cbeee0bb
Reviewed-on: https://pigweed-review.googlesource.com/c/open-dice/+/302861
Bot-Commit: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed-service-accounts.iam.gserviceaccount.com>
1 file changed
tree: 2f52a0b33b4e2a5cd6dd98f46821c9f2f1cda966
  1. build_overrides/
  2. docs/
  3. dpe-rs/
  4. images/
  5. include/
  6. src/
  7. third_party/
  8. toolchains/
  9. tools/
  10. .clang-format
  11. .gitignore
  12. .gitmodules
  13. .gn
  14. banner.txt
  15. bootstrap.sh
  16. BUILD.gn
  17. BUILDCONFIG.gn
  18. generate_test_values.py
  19. LICENSE
  20. navbar.md
  21. OWNERS
  22. pigweed.json
  23. pyproject.toml
  24. README.md
  25. run_fuzzer.sh
  26. rustfmt.toml
README.md

Open Profile for DICE

This repository contains the specification for the Open Profile for DICE along with production-quality code. This profile is a specialization of the Hardware Requirements for a Device Identifier Composition Engine and DICE Layering Architecture specifications published by the Trusted Computing Group (TCG). For readers already familiar with those specs, notable distinctives of this profile include:

  • Separate CDIs for attestation and sealing use cases
  • Categorized inputs, including values related to verified boot
  • Certified UDS values
  • X.509 or CBOR certificates

Mailing List

You can find us (and join us!) at https://groups.google.com/g/open-profile-for-dice. We're happy to answer questions and discuss proposed changes or features.

Specification

The specification can be found here. It is versioned using a major.minor scheme. Compatibility is maintained across minor versions but not necessarily across major versions.

Code

Production quality, portable C code is included. The main code is in dice.h and dice.c. Cryptographic and certificate generation operations are injected via a set of callbacks. Multiple implementations of these operations are provided, all equally acceptable. Integrators should choose just one of these, or write their own.

Tests are included for all code and the build files in this repository can be used to build and run these tests.

Disclaimer: This is not an officially supported Google product.

Thirdparty Dependencies

Different implementations use different third party libraries. The third_party directory contains build files and git submodules for each of these. The submodules must be initialized once after cloning the repo, using git submodule update --init, and updated after pulling commits that roll the submodules using git submodule update.

Building and Running Tests

Quick setup

To setup the build environment the first time:

$ git submodule update --init --recursive
$ source bootstrap.sh
$ gn gen out

To build and run tests:

$ ninja -C out

More details

The easiest way, and currently the only supported way, to build and run tests is from a Pigweed environment on Linux. Pigweed does support other host platforms so it shouldn't be too hard to get this running on Windows for example, but we use Linux.

There are two scripts to help set this up:

  • bootstrap.sh will initialize submodules, bootstrap a Pigweed environment, and generate build files. This can take some time and may download on the order of 1GB of dependencies so the normal workflow is to just do this once.

  • activate.sh quickly reactivates an environment that has been previously bootstrapped.

These scripts must be sourced into the current session: source activate.sh.

In the environment, from the base directory of the dice-profile checkout, run ninja -C out to build everything and run all tests. You can also run pw watch which will build, run tests, and continue to watch for changes.

This will build and run tests on the host using the clang toolchain. Pigweed makes it easy to configure other targets and toolchains. See toolchains/BUILD.gn and the Pigweed documentation.

Porting

The code is designed to be portable and should work with a variety of modern toolchains and in a variety of environments. The main code in dice.h and dice.c is C99; it uses uint8_t, size_t, and memcpy from the C standard library. The various ops implementations are as portable as their dependencies (often not C99 but still very portable). Notably, this code uses designated initializers for readability. This is a feature available in C since C99 but missing from C++ until C++20 where it appears in a stricter form.

Style

The Google C++ Style Guide is used. A .clang-format file is provided for convenience.

Incorporating

To incorporate the code into another project, there are a few options:

  • Copy only the necessary code. For example:

    1. Take the main code as is: include/dice/dice.h, src/dice.c

    2. Choose an implementation for crypto and certificate generation or choose to write your own. If you choose the boringssl implementation, for example, take include/dice/utils.h, include/dice/boringssl_ops.h, src/utils.c, and src/boringssl_ops.c. Taking a look at the library targets in BUILD.gn may be helpful.

  • Add this repository as a git submodule and integrate into the project build, optionally using the gn library targets provided.

  • Integrate into a project already using Pigweed using the gn build files provided.

Size Reports

The build reports code size using Bloaty McBloatface via the pw_bloat Pigweed module. There are two reports generated:

  • Library sizes - This report includes just the library code in this repository. It shows the baseline DICE code with no ops selected, and it shows the delta introduced by choosing various ops implementations. This report does not include the size of the third party dependencies.

  • Executable sizes - This report includes sizes for the library code in this repository plus all dependencies linked into a simple main function which makes a single DICE call with all-zero input. It shows the baseline DICE code with no ops (and therefore no dependencies other than libc), and it shows the delta introduced by choosing various ops implementations. This report does include the size of the third party dependencies. Note that rows specialized from ‘Boringssl Ops’ use that as a baseline for sizing.

The reports will be in the build output, but you can also find the reports in .txt files in the build output. For example, cat out/host_optimized/gen/*.txt | less will display all reports.

Thread Safety

This code does not itself use mutable global variables, or any other type of shared data structure so there is no thread-safety concerns. However, additional care is needed to ensure dependencies are configured to be thread-safe. For example, the current boringssl configuration defines OPENSSL_NO_THREADS_CORRUPT_MEMORY_AND_LEAK_SECRETS_IF_THREADED, and that would need to be changed before running in a threaded environment.

Clearing Sensitive Data

This code makes a reasonable effort to clear memory holding sensitive data. This may help with a broader strategy to clear sensitive data but it is not sufficient on its own. Here are a few things to consider.

  • The caller of this code is responsible for buffers they own (of course).
  • The ops implementations need to clear any copies they make of sensitive data. Both boringssl and mbedtls attempt to zeroize but this may need additional care to integrate correctly. For example, boringssl skips optimization prevention when OPENSSL_NO_ASM is defined (and it is currently defined).
  • Sensitive data may remain in cache.
  • Sensitive data may have been swapped out.
  • Sensitive data may be included in a crash dump.