feat: Add support for config templates

config/config.go

@@ -73,6 +73,17 @@ type SandboxConfig struct {
 	// Policies maps package manager names to their sandbox policy references.
 	// Key is package manager name (e.g., "npm", "pip"), value is policy reference.
 	Policies map[string]SandboxPolicyRef `mapstructure:"policies"`
+
+	// PolicyTemplates maps template names to their paths.
+	PolicyTemplates map[string]SandboxPolicyTemplate `mapstructure:"policy_templates"`
+}
+
+// SandboxPolicyTemplate defines a template for a sandbox policy, used to map
+// a profile name to a path.
+type SandboxPolicyTemplate struct {
+	// Path is the path to the template file.
+	// Relative path can be used to reference a template file in the config directory (example: ./npm-restrictive.yml)
+	Path string `mapstructure:"path"`
 }
 
 // SandboxPolicyRef references a sandbox policy for a specific package manager.
@@ -130,6 +141,11 @@ func (r *RuntimeConfig) EventLogDir() string {
 	return r.eventLogDir
 }
 
+// ConfigDir returns the path to the config directory.
+func (r *RuntimeConfig) ConfigDir() string {
+	return r.configDir
+}
+
 // DefaultConfig is a fail safe contract for the runtime configuration.
 // The config package return an appropriate RuntimeConfig based on the environment and the configuration.
 func DefaultConfig() RuntimeConfig {

config/config.template.yml

@@ -63,13 +63,22 @@ sandbox:
   # Enable sandbox mode (opt-in, default: false for backward compatibility)
   enabled: false
 
+  # Policy templates define policy profiles by name and path.
+  # They can be used to override a built-in profile or create a custom profile.
+  policy_templates:
+    # Name for the template. Can be used to override a built-in profile or create a custom profile.
+    # Path is the path to the template file.
+    # Relative path can be used to reference a template file in the config directory (example: ./npm-restrictive.yml)
+    npm-restrictive-override:
+      path: ./profiles/npm-restrictive.yml
+
   # Per-package-manager sandbox policies
   # Each package manager can have its own policy to account for unique security characteristics
   policies:
-    # npm ecosystem
+    # npm ecosystem. npm-restrictive is a built-in profile.
     npm:
       enabled: true
-      profile: npm-restrictive  # Built-in profile or path to custom YAML
+      profile: npm-restrictive  # Built-in profile, template name, or path to custom YAML
 
     pnpm:
       enabled: true
@@ -83,7 +92,7 @@ sandbox:
       enabled: true
       profile: npm-restrictive
 
-    # PyPI ecosystem
+    # PyPI ecosystem. pypi-restrictive is a built-in profile.
     pip:
       enabled: true
       profile: pypi-restrictive

sandbox/executor/apply.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"os/exec"
+	"path/filepath"
 
 	"github.com/safedep/dry/log"
 	"github.com/safedep/pmg/config"
@@ -11,14 +12,33 @@ import (
 	"github.com/safedep/pmg/sandbox/platform"
 )
 
+type applySandboxConfig struct {
+	sb sandbox.Sandbox
+}
+
+type applySandboxOpt func(*applySandboxConfig)
+
+// WithSandbox sets the sandbox to use for the command.
+// When not set, the sandbox will be determined by the platform.
+func WithSandbox(sb sandbox.Sandbox) applySandboxOpt {
+	return func(c *applySandboxConfig) {
+		c.sb = sb
+	}
+}
+
 // ApplySandbox applies sandbox isolation to the command if sandbox mode is enabled.
 // This is a helper function used by both guard and proxy flows to avoid code duplication.
 //
 // This is a security sensitive operation. If sandbox is enabled via. config but not available on the platform,
 // it will return an error to avoid running the command without sandbox protection.
-func ApplySandbox(ctx context.Context, cmd *exec.Cmd, pmName string) (*sandbox.ExecutionResult, error) {
+func ApplySandbox(ctx context.Context, cmd *exec.Cmd, pmName string, opts ...applySandboxOpt) (*sandbox.ExecutionResult, error) {
 	cfg := config.Get()
 
+	applyConfig := &applySandboxConfig{}
+	for _, opt := range opts {
+		opt(applyConfig)
+	}
+
 	if !cfg.Config.Sandbox.Enabled {
 		return sandbox.NewExecutionResult(), nil
 	}
@@ -57,9 +77,27 @@ func ApplySandbox(ctx context.Context, cmd *exec.Cmd, pmName string) (*sandbox.E
 
 		log.Debugf("Loading sandbox policy %s", policyRef.Profile)
 
-		policy, err = registry.GetProfile(policyRef.Profile)
-		if err != nil {
-			return nil, fmt.Errorf("failed to load sandbox policy %s: %w", policyRef.Profile, err)
+		// Check if there is a template for the policy and use it if it exists
+		// This is a way to override a built-in profile or create a custom profile.
+		if template, exists := cfg.Config.Sandbox.PolicyTemplates[policyRef.Profile]; exists {
+			if filepath.IsAbs(template.Path) {
+				policy, err = registry.GetProfile(template.Path)
+				if err != nil {
+					return nil, fmt.Errorf("failed to load sandbox policy %s: %w", template.Path, err)
+				}
+			} else {
+				policyPath := filepath.Join(cfg.ConfigDir(), template.Path)
+				policy, err = registry.GetProfile(policyPath)
+				if err != nil {
+					return nil, fmt.Errorf("failed to load sandbox policy %s: %w", policyPath, err)
+				}
+			}
+		} else {
+			// Load the policy from the registry by name
+			policy, err = registry.GetProfile(policyRef.Profile)
+			if err != nil {
+				return nil, fmt.Errorf("failed to load sandbox policy %s: %w", policyRef.Profile, err)
+			}
 		}
 	}
 
@@ -69,9 +107,14 @@ func ApplySandbox(ctx context.Context, cmd *exec.Cmd, pmName string) (*sandbox.E
 		return nil, fmt.Errorf("sandbox policy %s does not apply to %s", policy.Name, pmName)
 	}
 
-	sb, err := platform.NewSandbox()
-	if err != nil {
-		return nil, fmt.Errorf("sandbox not available on this platform: %v", err)
+	var sb sandbox.Sandbox
+	if applyConfig.sb != nil {
+		sb = applyConfig.sb
+	} else {
+		sb, err = platform.NewSandbox()
+		if err != nil {
+			return nil, fmt.Errorf("sandbox not available on this platform: %v", err)
+		}
 	}
 
 	if !sb.IsAvailable() {

sandbox/platform/seatbelt_translator_darwin.go

@@ -38,7 +38,12 @@ func (t *seatbeltPolicyTranslator) translate(policy *sandbox.SandboxPolicy) (str
 	sb.WriteString("(allow mach-lookup)\n")
 	sb.WriteString("(allow mach-register)\n")
 	sb.WriteString("(allow ipc-posix-shm)\n")
-	sb.WriteString("(allow signal)\n\n")
+	sb.WriteString("(allow signal)\n")
+	sb.WriteString(";; Allow reading file metadata for getcwd() and similar operations\n")
+	sb.WriteString("(allow file-read-metadata)\n")
+	sb.WriteString(";; Allow reading system configuration and libraries needed for process execution\n")
+	sb.WriteString("(allow file-read* (subpath \"/dev\"))\n")
+	sb.WriteString("(allow file-read* (subpath \"/etc\"))\n\n")
 
 	// Filesystem rules
 	if err := t.translateFilesystem(policy, &sb); err != nil {