* fix(kms): repair vault test call sites missed by the timeout refactor
Three offline tests still constructed VaultKmsClient with the pre-#5472
single-argument signature, leaving cargo test -p rustfs-kms unable to
compile. Pass the same 30s attempt timeout the neighbouring tests use.
* refactor(kms): route Vault clients through a rotatable credential provider
Both Vault backends previously built a VaultClient in their constructor
and held it for the lifetime of the backend, which leaves no seam for
re-authentication: rotating credentials would require tearing down the
whole backend.
Introduce backends/vault_credentials with a TokenSource trait (only
StaticToken for now; AppRole login and agent token files land in
follow-ups) and a VaultCredentialProvider that owns the authenticated
client behind an ArcSwap. Request paths take a per-call snapshot via
current(), so a future rotation swaps in a new client generation without
interrupting calls already in flight. Tokens held by this crate are
zeroized on drop, and Debug output of every credential-carrying type is
redacted (covered by a leak regression test).
Behavior is unchanged: static token, namespace, and per-attempt timeout
feed the same VaultClientSettings as before, and AppRole configurations
are still rejected at construction with the same message.
* fix(kms): restore vault backend test compilation after timeout parameter
PR #5472 added an attempt_timeout parameter to VaultKmsClient::new while
PR #5474 landed tests still using the one-argument form, leaving
'cargo test -p rustfs-kms' unable to compile on main. Pass the same
30-second timeout the surrounding integration tests already use.
* feat(kms): add master key version to data key envelope contract
DataKeyEnvelope gains an optional master_key_version field recording
which KEK version wrapped the DEK, so rotation-aware backends can load
the matching historical material on decrypt. The field is skipped when
None, keeping envelopes from non-rotating backends byte-identical to
the historical seven-field JSON shape, and legacy envelopes without the
field deserialize to None. The envelope discriminator marker is
untouched, so mixed-format routing is unchanged in both directions.
Adds the KeyVersionNotFound typed error for version-addressed material
lookups that must fail closed instead of falling back to the current
version.
Refs rustfs/backlog#1565
Zhengchao An