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/aws-sdk-go-v2/internal/configsources/config.go

@@ -0,0 +1,65 @@
+package configsources
+
+import (
+	"context"
+	"github.com/aws/aws-sdk-go-v2/aws"
+)
+
+// EnableEndpointDiscoveryProvider is an interface for retrieving external configuration value
+// for Enable Endpoint Discovery
+type EnableEndpointDiscoveryProvider interface {
+	GetEnableEndpointDiscovery(ctx context.Context) (value aws.EndpointDiscoveryEnableState, found bool, err error)
+}
+
+// ResolveEnableEndpointDiscovery extracts the first instance of a EnableEndpointDiscoveryProvider from the config slice.
+// Additionally returns a aws.EndpointDiscoveryEnableState to indicate if the value was found in provided configs,
+// and error if one is encountered.
+func ResolveEnableEndpointDiscovery(ctx context.Context, configs []interface{}) (value aws.EndpointDiscoveryEnableState, found bool, err error) {
+	for _, cfg := range configs {
+		if p, ok := cfg.(EnableEndpointDiscoveryProvider); ok {
+			value, found, err = p.GetEnableEndpointDiscovery(ctx)
+			if err != nil || found {
+				break
+			}
+		}
+	}
+	return
+}
+
+// UseDualStackEndpointProvider is an interface for retrieving external configuration values for UseDualStackEndpoint
+type UseDualStackEndpointProvider interface {
+	GetUseDualStackEndpoint(context.Context) (value aws.DualStackEndpointState, found bool, err error)
+}
+
+// ResolveUseDualStackEndpoint extracts the first instance of a UseDualStackEndpoint from the config slice.
+// Additionally returns a boolean to indicate if the value was found in provided configs, and error if one is encountered.
+func ResolveUseDualStackEndpoint(ctx context.Context, configs []interface{}) (value aws.DualStackEndpointState, found bool, err error) {
+	for _, cfg := range configs {
+		if p, ok := cfg.(UseDualStackEndpointProvider); ok {
+			value, found, err = p.GetUseDualStackEndpoint(ctx)
+			if err != nil || found {
+				break
+			}
+		}
+	}
+	return
+}
+
+// UseFIPSEndpointProvider is an interface for retrieving external configuration values for UseFIPSEndpoint
+type UseFIPSEndpointProvider interface {
+	GetUseFIPSEndpoint(context.Context) (value aws.FIPSEndpointState, found bool, err error)
+}
+
+// ResolveUseFIPSEndpoint extracts the first instance of a UseFIPSEndpointProvider from the config slice.
+// Additionally, returns a boolean to indicate if the value was found in provided configs, and error if one is encountered.
+func ResolveUseFIPSEndpoint(ctx context.Context, configs []interface{}) (value aws.FIPSEndpointState, found bool, err error) {
+	for _, cfg := range configs {
+		if p, ok := cfg.(UseFIPSEndpointProvider); ok {
+			value, found, err = p.GetUseFIPSEndpoint(ctx)
+			if err != nil || found {
+				break
+			}
+		}
+	}
+	return
+}