Add path attributes to indicate when operations should forward (#7175)

sdk/framework/backend.go

@@ -15,7 +15,8 @@ import (
 
 	"github.com/hashicorp/errwrap"
 	log "github.com/hashicorp/go-hclog"
-	multierror "github.com/hashicorp/go-multierror"
+	"github.com/hashicorp/go-multierror"
+	"github.com/hashicorp/vault/sdk/helper/consts"
 	"github.com/hashicorp/vault/sdk/helper/entropy"
 	"github.com/hashicorp/vault/sdk/helper/errutil"
 	"github.com/hashicorp/vault/sdk/helper/license"
@@ -225,6 +226,19 @@ func (b *Backend) HandleRequest(ctx context.Context, req *logical.Request) (*log
 
 	if path.Operations != nil {
 		if op, ok := path.Operations[req.Operation]; ok {
+
+			// Check whether this operation should be forwarded
+			replState := b.System().ReplicationState()
+			props := op.Properties()
+
+			if props.ForwardPerformanceStandby && replState.HasState(consts.ReplicationPerformanceStandby) {
+				return nil, logical.ErrReadOnly
+			}
+
+			if props.ForwardPerformanceSecondary && !b.System().LocalMount() && replState.HasState(consts.ReplicationPerformanceSecondary) {
+				return nil, logical.ErrReadOnly
+			}
+
 			callback = op.Handler()
 		}
 	} else {

sdk/framework/backend_test.go

@@ -9,6 +9,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/hashicorp/vault/sdk/helper/consts"
 	"github.com/hashicorp/vault/sdk/logical"
 )
 
@@ -93,6 +94,7 @@ func TestBackendHandleRequest(t *testing.T) {
 				},
 			},
 		},
+		system: &logical.StaticSystemView{},
 	}
 
 	for _, path := range []string{"foo/bar", "foo/baz/handler", "foo/both/handler"} {
@@ -114,6 +116,98 @@ func TestBackendHandleRequest(t *testing.T) {
 	}
 }
 
+func TestBackendHandleRequest_Forwarding(t *testing.T) {
+	tests := map[string]struct {
+		fwdStandby   bool
+		fwdSecondary bool
+		isLocal      bool
+		isStandby    bool
+		isSecondary  bool
+		expectFwd    bool
+	}{
+		"no forward": {
+			expectFwd: false,
+		},
+		"no forward, local restricted": {
+			isSecondary:  true,
+			fwdSecondary: true,
+			isLocal:      true,
+			expectFwd:    false,
+		},
+		"no forward, forwarding not requested": {
+			isSecondary: true,
+			isStandby:   true,
+			expectFwd:   false,
+		},
+		"forward, secondary": {
+			fwdSecondary: true,
+			isSecondary:  true,
+			expectFwd:    true,
+		},
+		"forward, standby": {
+			fwdStandby: true,
+			isStandby:  true,
+			expectFwd:  true,
+		},
+		"no forward, only secondary": {
+			fwdSecondary: true,
+			isStandby:    true,
+			expectFwd:    false,
+		},
+		"no forward, only standby": {
+			fwdStandby:  true,
+			isSecondary: true,
+			expectFwd:   false,
+		},
+	}
+
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			var replState consts.ReplicationState
+			if test.isStandby {
+				replState.AddState(consts.ReplicationPerformanceStandby)
+			}
+			if test.isSecondary {
+				replState.AddState(consts.ReplicationPerformanceSecondary)
+			}
+
+			b := &Backend{
+				Paths: []*Path{
+					{
+						Pattern: "foo",
+						Operations: map[logical.Operation]OperationHandler{
+							logical.ReadOperation: &PathOperation{
+								Callback: func(ctx context.Context, req *logical.Request, data *FieldData) (*logical.Response, error) {
+									return nil, nil
+								},
+								ForwardPerformanceSecondary: test.fwdSecondary,
+								ForwardPerformanceStandby:   test.fwdStandby,
+							},
+						},
+					},
+				},
+
+				system: &logical.StaticSystemView{
+					LocalMountVal:       test.isLocal,
+					ReplicationStateVal: replState,
+				},
+			}
+
+			_, err := b.HandleRequest(context.Background(), &logical.Request{
+				Operation: logical.ReadOperation,
+				Path:      "foo",
+			})
+
+			if !test.expectFwd && err != nil {
+				t.Fatalf("unexpected err: %v", err)
+			}
+			if test.expectFwd && err != logical.ErrReadOnly {
+				t.Fatalf("expected ErrReadOnly, got: %v", err)
+			}
+		})
+	}
+}
+
 func TestBackendHandleRequest_badwrite(t *testing.T) {
 	callback := func(ctx context.Context, req *logical.Request, data *FieldData) (*logical.Response, error) {
 		return &logical.Response{

sdk/framework/path.go

@@ -153,6 +153,14 @@ type OperationProperties struct {
 	// Deprecated indicates that this operation should be avoided.
 	Deprecated bool
 
+	// ForwardPerformanceStandby indicates that this path should not be processed
+	// on a performance standby node, and should be forwarded to the active node instead.
+	ForwardPerformanceStandby bool
+
+	// ForwardPerformanceSecondary indicates that this path should not be processed
+	// on a performance secondary node, and should be forwarded to the active node instead.
+	ForwardPerformanceSecondary bool
+
 	// DisplayAttrs provides hints for UI and documentation generators. They
 	// will be included in OpenAPI output if set.
 	DisplayAttrs *DisplayAttributes
@@ -213,6 +221,8 @@ type PathOperation struct {
 	Responses                   map[int][]Response
 	Unpublished                 bool
 	Deprecated                  bool
+	ForwardPerformanceSecondary bool
+	ForwardPerformanceStandby   bool
 }
 
 func (p *PathOperation) Handler() OperationFunc {
@@ -227,6 +237,8 @@ func (p *PathOperation) Properties() OperationProperties {
 		Examples:                    p.Examples,
 		Unpublished:                 p.Unpublished,
 		Deprecated:                  p.Deprecated,
+		ForwardPerformanceSecondary: p.ForwardPerformanceSecondary,
+		ForwardPerformanceStandby:   p.ForwardPerformanceStandby,
 	}
 }