* Move storage clients to separate packages
* Allow setting of client credentials for AWS S3
* Use managed identity client secret or default credentials for Azure Blob Storage
* Use credentials file to authorize GCS client
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Signed-off-by: Daniel Weiße <dw@edgeless.systems>
The variable VersionInfo is supposed to be set by `go build -X ...` during link time but should not be modified at runtime.
This change ensures the underlying var is private and can only be accessed by a public getter.
* Replace external KMS backend logic for AWS, Azure, and GCP with go-kms-wrapping
* Move kms client setup config into its own package for easier parsing
* Update kms integration flag naming
* Error if nil storage is passed to external KMS
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Signed-off-by: Daniel Weiße <dw@edgeless.systems>
So far the masterSecret was sent to the initial bootstrapper
on init/recovery. With this commit this information is encoded
in the kmsURI that is sent during init.
For recover, the communication with the recoveryserver is
changed. Before a streaming gRPC call was used to
exchanges UUID for measurementSecret and state disk key.
Now a standard gRPC is made that includes the same kmsURI &
storageURI that are sent during init.
In the light of extending our eKMS support it will be helpful
to have a tighter use of the word "KMS".
KMS should refer to the actual component that manages keys.
The keyservice, also called KMS in the constellation code,
does not manage keys itself. It talks to a KMS backend,
which in turn does the actual key management.
