https://git.schokokeks.org/derivepassphrase.git/tree/ef6258d3cec6e30cda8968f822b223aaf0cb0f8a Recent commits feed provided by GitList. * t/issue12-ssh-agent-spawning: Remove debugging-only code and add missing docstring in pytest fixtures https://git.schokokeks.org/derivepassphrase.git/commit/ef6258d3cec6e30cda8968f822b223aaf0cb0f8a software@the13thletter.info (Marco Ricci) Sun, 22 Sep 2024 19:23:07 +0200 ef6258d3cec6e30cda8968f822b223aaf0cb0f8a https://git.schokokeks.org/derivepassphrase.git/commit/d01a4dc9631e6281c268228d281903643147e3f8 software@the13thletter.info (Marco Ricci) Sun, 22 Sep 2024 19:19:38 +0200 d01a4dc9631e6281c268228d281903643147e3f8 * t/issue12-ssh-agent-spawning: Add Changelog entry for the test suite SSH agent spawner Add test fixture for manually spawning known SSH agents Retire non-repeatability check for unsuitable SSH keys in the tests Add principal support for uploading SSH keys to the agent Simplify some SSH agent key uploading tests Support passing expected SSH agent response codes GitHub: Closes #12. https://git.schokokeks.org/derivepassphrase.git/commit/dd606b3a051f0ba3bc76d0ef6e14ba3fb5d87298 software@the13thletter.info (Marco Ricci) Sun, 22 Sep 2024 18:40:33 +0200 dd606b3a051f0ba3bc76d0ef6e14ba3fb5d87298 https://git.schokokeks.org/derivepassphrase.git/commit/0f8ad24096b08640eb38687821d09f13a656967c software@the13thletter.info (Marco Ricci) Sun, 22 Sep 2024 18:36:19 +0200 0f8ad24096b08640eb38687821d09f13a656967c Include pytest fixtures to spawn known SSH agents and interface with the running SSH agent, in an agent-agnostic way. Move the key loading parts from the test functions into the test fixtures. This generally makes the actual test functions somewhat cleaner and easier to read, but because the monkeypatch fixture interferes with these new fixtures, the net improvements to readibility are only moderate. The test functions do however profit directly from reduced copy-and-paste in the key loading part. Pageant is one of the supported agents, and it behaves markedly differently than OpenSSH's agent. In particular, Pageant does not support adding keys with constraints or re-submitting a key it is already holding, and *every* key type Pageant currently offers yields a deterministic signature. Furthermore, a bug concerning output buffering in Pageant 0.81 and lower currently makes it impossible to use Pageant as a subprocess properly without correctly guessing the socket address. (This has already been reported upstream.) On the other hand, Pageant supports ed448 keys, which OpenSSH doesn't. So, implementing support for Pageant was very valuable to highlight areas where the code made unreasonable assumptions about SSH agent behavior, in particular the availability and behavior of the system SSH agent service. The new fixtures live in `tests/conftest.py`, following a relevant pytest convention. The fixtures themselves are necessarily platform- and runtime-dependent, so even though they are test code that should be included in test coverage, all parts dealing with querying the system, spawning programs, error handling related to the former and ensuring a certain functionality is available (or skipping the test otherwise) are excluded from test coverage. In particular, this includes the entire fixture to ensure a running agent, and the cleanup part of the agent with loaded keys fixture; I have however tried various constellations by hand to ensure the code works if certain agents are available or unavailable. https://git.schokokeks.org/derivepassphrase.git/commit/63b51df7a39fd642ca079ac390014d23f617b972 software@the13thletter.info (Marco Ricci) Sun, 22 Sep 2024 16:37:58 +0200 63b51df7a39fd642ca079ac390014d23f617b972 DSA and ECDSA keys use a nonce during signing, and it is well-known that reusing the nonce for another signature allows the private key to be derived directly from those two signatures. Because of this, many implementations choose the nonce via a high-quality random number generator. This leads to DSA and ECDSA signatures being non-repeatable, i.e. signing the same document twice leads to two different signatures/binary strings. OpenSSH's agent behaves this way. However, various implementations of DSA or DSA variants have attempted to find a way to avoid the random number generator by choosing the nonce deterministically (but still unpredictably, for an attacker): EdDSA mandates a specific nonce as part of the specification, and RFC 6979 outlines a different deterministic nonce scheme for all (other) DSA variants. All versions of PuTTY/Pageant use deterministic nonce generation (a homegrown system in 0.80 and lower, RFC 6979 afterwards), so DSA and ECDSA signatures by Pageant *are* repeatable. And there is no reason why OpenSSH couldn't adopt RFC 6979 in the future. Therefore, remove the check for repeatability in the tests. The `Vault` class check for key suitability remains unchanged, because while DSA/ECDSA keys *can* use repeatable signatures, such use is not *guaranteed*. https://git.schokokeks.org/derivepassphrase.git/commit/7c1d055316e9e6a254c91e9b9f206cddbec4df8f software@the13thletter.info (Marco Ricci) Sat, 21 Sep 2024 12:17:48 +0200 7c1d055316e9e6a254c91e9b9f206cddbec4df8f Add the necessary protocol numbers to the `SSH_AGENT` and `SSH_AGENTC` enums, and the necessary `private_key_blob` data to the `tests.SUPPORTED_KEYS` and `tests.UNSUITABLE_KEYS` objects. This suffices for key uploads without constraints, but adding a key *with* constraints still requires knowledge about the encoding of the constraints in the agent protocol. https://git.schokokeks.org/derivepassphrase.git/commit/3035794147127de9be9b42cf96353e598389b71a software@the13thletter.info (Marco Ricci) Sat, 21 Sep 2024 12:10:20 +0200 3035794147127de9be9b42cf96353e598389b71a Remove unused test parameters, which were used solely for display purposes to generate a readable test ID. Instead of this, use the `ids` parameter of `pytest.mark.parametrize` directly. https://git.schokokeks.org/derivepassphrase.git/commit/ddce2cbfe9821f95d24d3e2649edbac6f3801574 software@the13thletter.info (Marco Ricci) Sat, 21 Sep 2024 11:58:57 +0200 ddce2cbfe9821f95d24d3e2649edbac6f3801574 This shifts the remaining error checking into the `SSHAgentClient.request` method, most of the time. On the other hand, this makes mocking that method somewhat more involved. https://git.schokokeks.org/derivepassphrase.git/commit/2bb23da7602076aa37f43c3363f6cfcee91f59bd software@the13thletter.info (Marco Ricci) Sat, 21 Sep 2024 11:45:20 +0200 2bb23da7602076aa37f43c3363f6cfcee91f59bd https://git.schokokeks.org/derivepassphrase.git/commit/df459996c5d005264830175d20a149002266e13e m@the13thletter.info (Marco Ricci) Thu, 12 Sep 2024 13:59:16 +0200 df459996c5d005264830175d20a149002266e13e