feat(ssrf): implement an SSRF protection mechanism BE-13021 (#2818)

api/stacks/stackutils/validation.go

@@ -2,10 +2,13 @@ package stackutils
 
 import (
 	"context"
+	"fmt"
 	"path"
+	"strings"
 
 	portainer "github.com/portainer/portainer/api"
 	"github.com/portainer/portainer/api/filesystem"
+	"github.com/portainer/portainer/pkg/libhttp/ssrf"
 
 	composeloader "github.com/compose-spec/compose-go/v2/loader"
 	composetypes "github.com/compose-spec/compose-go/v2/types"
@@ -68,6 +71,97 @@ func IsValidStackFile(config StackFileValidationConfig) error {
 	return nil
 }
 
+// ValidateComposeURLs parses each stack file and checks that every external URL
+// (build contexts and image registry hostnames) is permitted by the active SSRF
+// policy. It is a no-op when SSRF protection is disabled.
+func ValidateComposeURLs(ctx context.Context, stack *portainer.Stack, fileService portainer.FileService) error {
+	if !ssrf.IsEnabled() {
+		return nil
+	}
+
+	env := BuildEnvMap(stack)
+	workingDir := filesystem.JoinPaths(stack.ProjectPath, path.Dir(stack.EntryPoint))
+
+	for _, file := range GetStackFilePaths(stack, false) {
+		stackContent, err := fileService.GetFileContent(stack.ProjectPath, file)
+		if err != nil {
+			return errors.Wrap(err, "failed to get stack file content")
+		}
+
+		if err := checkComposeFileURLs(ctx, stackContent, env, workingDir); err != nil {
+			return errors.Wrap(err, "stack file contains a URL blocked by the SSRF policy")
+		}
+	}
+
+	return nil
+}
+
+// ValidateEdgeStackComposeContent checks that every external URL in an edge
+// stack's Compose file is permitted by the active SSRF policy. It is a no-op
+// when SSRF protection is disabled or the deployment type is not compose.
+func ValidateEdgeStackComposeContent(ctx context.Context, deploymentType portainer.EdgeStackDeploymentType, content []byte) error {
+	if !ssrf.IsEnabled() || deploymentType != portainer.EdgeStackDeploymentCompose {
+		return nil
+	}
+
+	if err := checkComposeFileURLs(ctx, content, nil, ""); err != nil {
+		return errors.Wrap(err, "stack file contains a URL blocked by the SSRF policy")
+	}
+
+	return nil
+}
+
+func checkComposeFileURLs(ctx context.Context, content []byte, env map[string]string, workingDir string) error {
+	composeConfigDetails := composetypes.ConfigDetails{
+		ConfigFiles: []composetypes.ConfigFile{{Content: content}},
+		Environment: env,
+		WorkingDir:  workingDir,
+	}
+
+	composeConfig, err := composeloader.LoadWithContext(ctx, composeConfigDetails, composeloader.WithSkipValidation)
+	if err != nil {
+		return err
+	}
+
+	for _, service := range composeConfig.Services {
+		if service.Build != nil {
+			buildCtx := service.Build.Context
+			if strings.HasPrefix(buildCtx, "http://") || strings.HasPrefix(buildCtx, "https://") {
+				if err := ssrf.CheckURL(ctx, buildCtx); err != nil {
+					return fmt.Errorf("service %q: build context URL blocked: %w", service.Name, err)
+				}
+			}
+		}
+
+		if service.Image != "" {
+			if registry := extractImageRegistry(service.Image); registry != "" {
+				if err := ssrf.CheckURL(ctx, "https://"+registry); err != nil {
+					return fmt.Errorf("service %q: image registry %q blocked: %w", service.Name, registry, err)
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// extractImageRegistry returns the registry hostname from an OCI image reference,
+// or an empty string if the image resolves to Docker Hub (no explicit registry).
+func extractImageRegistry(imageRef string) string {
+	ref, _, _ := strings.Cut(imageRef, "@")
+
+	first, _, hasSlash := strings.Cut(ref, "/")
+	if !hasSlash {
+		return ""
+	}
+
+	if strings.ContainsAny(first, ".:") || first == "localhost" {
+		return first
+	}
+
+	return ""
+}
+
 func ValidateStackFiles(stack *portainer.Stack, securitySettings *portainer.EndpointSecuritySettings, fileService portainer.FileService) error {
 	env := BuildEnvMap(stack)
 	workingDir := filesystem.JoinPaths(stack.ProjectPath, path.Dir(stack.EntryPoint))