errLifecycleInvalidDeleteMarker = Errorf("Delete marker cannot be specified with Days or Date in a Lifecycle Expiration Policy")
	errLifecycleDateNotMidnight     = Errorf("'Date' must be at midnight GMT")
	errLifecycleInvalidDeleteAll    = Errorf("Days (positive integer) should be present inside Expiration with ExpiredObjectAllVersions.")
)

// an object is encrypted using SSE-C or SSE-KMS. Maybe AWS S3
// computes the ETag as MD5 of the encrypted content but there is
// no way to verify this assumption since the encryption happens
// inside AWS S3.
// Therefore, S3 clients must not make any assumption about ETags
// in case of SSE-C or SSE-KMS except that the ETag is well-formed.
//
// To put all of this into a simple rule:
//
//	SSE-S3 : ETag == MD5