rbd: add aws-sts-metdata encryption type

With Amazon STS and kubernetes cluster is configured with
OIDC identity provider, credentials to access Amazon KMS
can be fetched using oidc-token(serviceaccount token).
Each tenant/namespace needs to create a secret with aws region,
role and CMK ARN.
Ceph-CSI will assume the given role with oidc token and access
aws KMS, with given CMK to encrypt/decrypt DEK which will stored
in the image metdata.

Refer: https://docs.aws.amazon.com/STS/latest/APIReference/welcome.html
Resolves: #2879

Signed-off-by: Rakshith R <rar@redhat.com>

vendor/github.com/aws/smithy-go/middleware/step_deserialize.go

@@ -0,0 +1,217 @@
+package middleware
+
+import (
+	"context"
+)
+
+// DeserializeInput provides the input parameters for the DeserializeInput to
+// consume. DeserializeMiddleware should not modify the Request, and instead
+// forward it along to the next DeserializeHandler.
+type DeserializeInput struct {
+	Request interface{}
+}
+
+// DeserializeOutput provides the result returned by the next
+// DeserializeHandler. The DeserializeMiddleware should deserialize the
+// RawResponse into a Result that can be consumed by middleware higher up in
+// the stack.
+type DeserializeOutput struct {
+	RawResponse interface{}
+	Result      interface{}
+}
+
+// DeserializeHandler provides the interface for the next handler the
+// DeserializeMiddleware will call in the middleware chain.
+type DeserializeHandler interface {
+	HandleDeserialize(ctx context.Context, in DeserializeInput) (
+		out DeserializeOutput, metadata Metadata, err error,
+	)
+}
+
+// DeserializeMiddleware provides the interface for middleware specific to the
+// serialize step. Delegates to the next DeserializeHandler for further
+// processing.
+type DeserializeMiddleware interface {
+	// ID returns a unique ID for the middleware in the DeserializeStep. The step does not
+	// allow duplicate IDs.
+	ID() string
+
+	// HandleDeserialize invokes the middleware behavior which must delegate to the next handler
+	// for the middleware chain to continue. The method must return a result or
+	// error to its caller.
+	HandleDeserialize(ctx context.Context, in DeserializeInput, next DeserializeHandler) (
+		out DeserializeOutput, metadata Metadata, err error,
+	)
+}
+
+// DeserializeMiddlewareFunc returns a DeserializeMiddleware with the unique ID
+// provided, and the func to be invoked.
+func DeserializeMiddlewareFunc(id string, fn func(context.Context, DeserializeInput, DeserializeHandler) (DeserializeOutput, Metadata, error)) DeserializeMiddleware {
+	return deserializeMiddlewareFunc{
+		id: id,
+		fn: fn,
+	}
+}
+
+type deserializeMiddlewareFunc struct {
+	// Unique ID for the middleware.
+	id string
+
+	// Middleware function to be called.
+	fn func(context.Context, DeserializeInput, DeserializeHandler) (
+		DeserializeOutput, Metadata, error,
+	)
+}
+
+// ID returns the unique ID for the middleware.
+func (s deserializeMiddlewareFunc) ID() string { return s.id }
+
+// HandleDeserialize invokes the middleware Fn.
+func (s deserializeMiddlewareFunc) HandleDeserialize(ctx context.Context, in DeserializeInput, next DeserializeHandler) (
+	out DeserializeOutput, metadata Metadata, err error,
+) {
+	return s.fn(ctx, in, next)
+}
+
+var _ DeserializeMiddleware = (deserializeMiddlewareFunc{})
+
+// DeserializeStep provides the ordered grouping of DeserializeMiddleware to be
+// invoked on a handler.
+type DeserializeStep struct {
+	ids *orderedIDs
+}
+
+// NewDeserializeStep returns a DeserializeStep ready to have middleware for
+// initialization added to it.
+func NewDeserializeStep() *DeserializeStep {
+	return &DeserializeStep{
+		ids: newOrderedIDs(),
+	}
+}
+
+var _ Middleware = (*DeserializeStep)(nil)
+
+// ID returns the unique ID of the step as a middleware.
+func (s *DeserializeStep) ID() string {
+	return "Deserialize stack step"
+}
+
+// HandleMiddleware invokes the middleware by decorating the next handler
+// provided. Returns the result of the middleware and handler being invoked.
+//
+// Implements Middleware interface.
+func (s *DeserializeStep) HandleMiddleware(ctx context.Context, in interface{}, next Handler) (
+	out interface{}, metadata Metadata, err error,
+) {
+	order := s.ids.GetOrder()
+
+	var h DeserializeHandler = deserializeWrapHandler{Next: next}
+	for i := len(order) - 1; i >= 0; i-- {
+		h = decoratedDeserializeHandler{
+			Next: h,
+			With: order[i].(DeserializeMiddleware),
+		}
+	}
+
+	sIn := DeserializeInput{
+		Request: in,
+	}
+
+	res, metadata, err := h.HandleDeserialize(ctx, sIn)
+	return res.Result, metadata, err
+}
+
+// Get retrieves the middleware identified by id. If the middleware is not present, returns false.
+func (s *DeserializeStep) Get(id string) (DeserializeMiddleware, bool) {
+	get, ok := s.ids.Get(id)
+	if !ok {
+		return nil, false
+	}
+	return get.(DeserializeMiddleware), ok
+}
+
+// Add injects the middleware to the relative position of the middleware group.
+// Returns an error if the middleware already exists.
+func (s *DeserializeStep) Add(m DeserializeMiddleware, pos RelativePosition) error {
+	return s.ids.Add(m, pos)
+}
+
+// Insert injects the middleware relative to an existing middleware ID.
+// Returns error if the original middleware does not exist, or the middleware
+// being added already exists.
+func (s *DeserializeStep) Insert(m DeserializeMiddleware, relativeTo string, pos RelativePosition) error {
+	return s.ids.Insert(m, relativeTo, pos)
+}
+
+// Swap removes the middleware by id, replacing it with the new middleware.
+// Returns the middleware removed, or error if the middleware to be removed
+// doesn't exist.
+func (s *DeserializeStep) Swap(id string, m DeserializeMiddleware) (DeserializeMiddleware, error) {
+	removed, err := s.ids.Swap(id, m)
+	if err != nil {
+		return nil, err
+	}
+
+	return removed.(DeserializeMiddleware), nil
+}
+
+// Remove removes the middleware by id. Returns error if the middleware
+// doesn't exist.
+func (s *DeserializeStep) Remove(id string) (DeserializeMiddleware, error) {
+	removed, err := s.ids.Remove(id)
+	if err != nil {
+		return nil, err
+	}
+
+	return removed.(DeserializeMiddleware), nil
+}
+
+// List returns a list of the middleware in the step.
+func (s *DeserializeStep) List() []string {
+	return s.ids.List()
+}
+
+// Clear removes all middleware in the step.
+func (s *DeserializeStep) Clear() {
+	s.ids.Clear()
+}
+
+type deserializeWrapHandler struct {
+	Next Handler
+}
+
+var _ DeserializeHandler = (*deserializeWrapHandler)(nil)
+
+// HandleDeserialize implements DeserializeHandler, converts types and delegates to underlying
+// generic handler.
+func (w deserializeWrapHandler) HandleDeserialize(ctx context.Context, in DeserializeInput) (
+	out DeserializeOutput, metadata Metadata, err error,
+) {
+	resp, metadata, err := w.Next.Handle(ctx, in.Request)
+	return DeserializeOutput{
+		RawResponse: resp,
+	}, metadata, err
+}
+
+type decoratedDeserializeHandler struct {
+	Next DeserializeHandler
+	With DeserializeMiddleware
+}
+
+var _ DeserializeHandler = (*decoratedDeserializeHandler)(nil)
+
+func (h decoratedDeserializeHandler) HandleDeserialize(ctx context.Context, in DeserializeInput) (
+	out DeserializeOutput, metadata Metadata, err error,
+) {
+	return h.With.HandleDeserialize(ctx, in, h.Next)
+}
+
+// DeserializeHandlerFunc provides a wrapper around a function to be used as a deserialize middleware handler.
+type DeserializeHandlerFunc func(context.Context, DeserializeInput) (DeserializeOutput, Metadata, error)
+
+// HandleDeserialize invokes the wrapped function with the given arguments.
+func (d DeserializeHandlerFunc) HandleDeserialize(ctx context.Context, in DeserializeInput) (DeserializeOutput, Metadata, error) {
+	return d(ctx, in)
+}
+
+var _ DeserializeHandler = DeserializeHandlerFunc(nil)