* logical/aws: Harden WAL entry creation
If AWS IAM user creation failed in any way, the WAL corresponding to the
IAM user would get left around and Vault would try to roll it back.
However, because the user never existed, the rollback failed. Thus, the
WAL would essentially get "stuck" and Vault would continually attempt to
roll it back, failing every time. A similar situation could arise if the
IAM user that Vault created got deleted out of band, or if Vault deleted
it but was unable to write the lease revocation back to storage (e.g., a
storage failure).
This attempts to harden it in two ways. One is by deleting the WAL log
entry if the IAM user creation fails. However, the WAL deletion could
still fail, and this wouldn't help where the user is deleted out of
band, so second, consider the user rolled back if the user just doesn't
exist, under certain circumstances.
Fixes#5190
* Fix segfault in expiration unit tests
TestExpiration_Tidy was passing in a leaseEntry that had a nil Secret,
which then caused a segfault as the changes to revokeEntry didn't check
whether Secret was nil; this is probably unlikely to occur in real life,
but good to be extra cautious.
* Fix potential segfault
Missed the else...
* Respond to PR feedback
* govet cleanup in token store
* adding general ttl handling to login requests
* consolidating TTL calculation to system view
* deprecate LeaseExtend
* deprecate LeaseExtend
* set the increment to the correct value
* move calculateTTL out of SystemView
* remove unused value
* add back clearing of lease id
* implement core ttl in some backends
* removing increment and issue time from lease options
* adding ttl tests, fixing some compile issue
* adding ttl tests
* fixing some explicit max TTL logic
* fixing up some tests
* removing unneeded test
* off by one errors...
* adding back some logic for bc
* adding period to return on renewal
* tweaking max ttl capping slightly
* use the appropriate precision for ttl calculation
* deprecate proto fields instead of delete
* addressing feedback
* moving TTL handling for backends to core
* mongo is a secret backend not auth
* adding estimated ttl for backends that also manage the expiration time
* set the estimate values before calling the renew request
* moving calculate TTL to framework, revert removal of increment and issue time from logical
* minor edits
* addressing feedback
* address more feedback
