Update AWS auth method certificates
Add tests that the `rsa2048` document can also be verified using the
`pkcs7` field for AWS auth.
Due to the use of SHA-1-based signatures for the `identity` and `pkcs7`
methods, we want to encourage moving toward using the RSA 2048 workflow,
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/verify-rsa2048.html
This doesn't require code changes for Vault necessarily, but adding in
the (many) certificates will help end users.
Also adds `rsa2048` option to API to fetch the RSA 2048 signature.
I will make a PR to update to the AWS auth docs to document the RSA 2048
flow soon after this.
* Native Login method, userpass and approle interfaces to implement it
* Add AWS auth interface for Login, unexported struct fields for now
* Add Kubernetes client login
* Add changelog
* Add a test for approle client login
* Return errors from LoginOptions, use limited reader for secret ID
* Fix auth comment length
* Return actual type not interface, check for client token in tests
* Require specification of secret ID location using SecretID struct as AppRole arg
* Allow password from env, file, or plaintext
* Add flexibility in how to fetch k8s service token, but still with default
* Avoid passing strings that need to be validated by just having different login options
* Try a couple real tests with approle and userpass login
* Fix method name in comment
* Add context to Login methods, remove comments about certain sources being inherently insecure
* Perform read of secret ID at login time
* Read password from file at login time
* Pass context in integ tests
* Read env var values in at login time, add extra tests
* Update api version
* Revert "Update api version"
This reverts commit 1ef3949497.
* Update api version in all go.mod files
