Andrew Chow 679f825ba3
Merge bitcoin/bitcoin#27479: BIP324: ElligatorSwift integrations
3168b08043546cd248a81563e21ff096019f1521 Bench test for EllSwift ECDH (Pieter Wuille)
42d759f239d1842ec0c662f8fa9ac0a9ff18a2cb Bench tests for CKey->EllSwift (dhruv)
2e5a8a437cf9ac78548891e61797b394571e27ae Fuzz test for Ellswift ECDH (dhruv)
c3ac9f5cf413e263803aac668a90a4ddd7316924 Fuzz test for CKey->EllSwift->CPubKey creation/decoding (dhruv)
aae432a764e4ceb7eac305458e585726225c7189 Unit test for ellswift creation/decoding roundtrip (dhruv)
eff72a0dff8fa83af873ad9b15dbac50b8d4eca3 Add ElligatorSwift key creation and ECDH logic (Pieter Wuille)
42239f839081bba9a426ebb9f1b7a56e35a2d428 Enable ellswift module in libsecp256k1 (dhruv)
901336eee751de088465e313dd8b500dfaf462b2 Squashed 'src/secp256k1/' changes from 4258c54f4e..705ce7ed8c (Pieter Wuille)

Pull request description:

  This replaces #23432 and part of #23561.

  This PR introduces all of the ElligatorSwift-related changes (libsecp256k1 updates, generation, decoding, ECDH, tests, fuzzing, benchmarks) needed for BIP324.

  ElligatorSwift is a special 64-byte encoding format for public keys introduced in libsecp256k1 in https://github.com/bitcoin-core/secp256k1/pull/1129. It has the property that *every* 64-byte array is a valid encoding for some public key, and every key has approximately $2^{256}$ encodings. Furthermore, it is possible to efficiently generate a uniformly random encoding for a given public key or private key. This is used for the key exchange phase in BIP324, to achieve a byte stream that is entirely pseudorandom, even before the shared encryption key is established.

ACKs for top commit:
  instagibbs:
    reACK 3168b08043
  achow101:
    ACK 3168b08043546cd248a81563e21ff096019f1521
  theStack:
    re-ACK 3168b08043546cd248a81563e21ff096019f1521

Tree-SHA512: 308ac3d33e9a2deecb65826cbf0390480a38de201918429c35c796f3421cdf94c5501d027a043ae8f012cfaa0584656da1de6393bfba3532ab4c20f9533f06a6
2023-06-26 17:08:03 -04:00
..
2023-03-23 12:55:18 +01:00
2022-12-24 23:49:50 +00:00

Unit tests

The sources in this directory are unit test cases. Boost includes a unit testing framework, and since Bitcoin Core already uses Boost, it makes sense to simply use this framework rather than require developers to configure some other framework (we want as few impediments to creating unit tests as possible).

The build system is set up to compile an executable called test_bitcoin that runs all of the unit tests. The main source file for the test library is found in util/setup_common.cpp.

Compiling/running unit tests

Unit tests will be automatically compiled if dependencies were met in ./configure and tests weren't explicitly disabled.

After configuring, they can be run with make check.

To run the unit tests manually, launch src/test/test_bitcoin. To recompile after a test file was modified, run make and then run the test again. If you modify a non-test file, use make -C src/test to recompile only what's needed to run the unit tests.

To add more unit tests, add BOOST_AUTO_TEST_CASE functions to the existing .cpp files in the test/ directory or add new .cpp files that implement new BOOST_AUTO_TEST_SUITE sections.

To run the GUI unit tests manually, launch src/qt/test/test_bitcoin-qt

To add more GUI unit tests, add them to the src/qt/test/ directory and the src/qt/test/test_main.cpp file.

Running individual tests

test_bitcoin accepts the command line arguments from the boost framework. For example, to run just the getarg_tests suite of tests:

test_bitcoin --log_level=all --run_test=getarg_tests

log_level controls the verbosity of the test framework, which logs when a test case is entered, for example. test_bitcoin also accepts the command line arguments accepted by bitcoind. Use -- to separate both types of arguments:

test_bitcoin --log_level=all --run_test=getarg_tests -- -printtoconsole=1

The -printtoconsole=1 after the two dashes redirects the debug log, which would normally go to a file in the test datadir (BasicTestingSetup::m_path_root), to the standard terminal output.

... or to run just the doubledash test:

test_bitcoin --run_test=getarg_tests/doubledash

Run test_bitcoin --help for the full list.

Adding test cases

To add a new unit test file to our test suite you need to add the file to src/Makefile.test.include. The pattern is to create one test file for each class or source file for which you want to create unit tests. The file naming convention is <source_filename>_tests.cpp and such files should wrap their tests in a test suite called <source_filename>_tests. For an example of this pattern, see uint256_tests.cpp.

Logging and debugging in unit tests

make check will write to a log file foo_tests.cpp.log and display this file on failure. For running individual tests verbosely, refer to the section above.

To write to logs from unit tests you need to use specific message methods provided by Boost. The simplest is BOOST_TEST_MESSAGE.

For debugging you can launch the test_bitcoin executable with gdb or lldb and start debugging, just like you would with any other program:

gdb src/test/test_bitcoin

Segmentation faults

If you hit a segmentation fault during a test run, you can diagnose where the fault is happening by running gdb ./src/test/test_bitcoin and then using the bt command within gdb.

Another tool that can be used to resolve segmentation faults is valgrind.

If for whatever reason you want to produce a core dump file for this fault, you can do that as well. By default, the boost test runner will intercept system errors and not produce a core file. To bypass this, add --catch_system_errors=no to the test_bitcoin arguments and ensure that your ulimits are set properly (e.g. ulimit -c unlimited).

Running the tests and hitting a segmentation fault should now produce a file called core (on Linux platforms, the file name will likely depend on the contents of /proc/sys/kernel/core_pattern).

You can then explore the core dump using

gdb src/test/test_bitcoin core

(gbd) bt  # produce a backtrace for where a segfault occurred