Initial commit

internal/sandbox/dangerous.go

@@ -0,0 +1,84 @@
+// Package sandbox provides sandboxing functionality for macOS and Linux.
+package sandbox
+
+import (
+	"os"
+	"path/filepath"
+)
+
+// DangerousFiles lists files that should be protected from writes.
+// These files can be used for code execution or data exfiltration.
+var DangerousFiles = []string{
+	".gitconfig",
+	".gitmodules",
+	".bashrc",
+	".bash_profile",
+	".zshrc",
+	".zprofile",
+	".profile",
+	".ripgreprc",
+	".mcp.json",
+}
+
+// DangerousDirectories lists directories that should be protected from writes.
+// Excludes .git since we need it writable for git operations.
+var DangerousDirectories = []string{
+	".vscode",
+	".idea",
+	".claude/commands",
+	".claude/agents",
+}
+
+// GetDefaultWritePaths returns system paths that should be writable for commands to work.
+func GetDefaultWritePaths() []string {
+	home, _ := os.UserHomeDir()
+
+	paths := []string{
+		"/dev/stdout",
+		"/dev/stderr",
+		"/dev/null",
+		"/dev/tty",
+		"/dev/dtracehelper",
+		"/dev/autofs_nowait",
+		"/tmp/fence",
+		"/private/tmp/fence",
+	}
+
+	if home != "" {
+		paths = append(paths,
+			filepath.Join(home, ".npm/_logs"),
+			filepath.Join(home, ".fence/debug"),
+		)
+	}
+
+	return paths
+}
+
+// GetMandatoryDenyPatterns returns glob patterns for paths that must always be protected.
+func GetMandatoryDenyPatterns(cwd string, allowGitConfig bool) []string {
+	var patterns []string
+
+	// Dangerous files - in CWD and all subdirectories
+	for _, f := range DangerousFiles {
+		patterns = append(patterns, filepath.Join(cwd, f))
+		patterns = append(patterns, "**/"+f)
+	}
+
+	// Dangerous directories
+	for _, d := range DangerousDirectories {
+		patterns = append(patterns, filepath.Join(cwd, d))
+		patterns = append(patterns, "**/"+d+"/**")
+	}
+
+	// Git hooks are always blocked
+	patterns = append(patterns, filepath.Join(cwd, ".git/hooks"))
+	patterns = append(patterns, "**/.git/hooks/**")
+
+	// Git config is conditionally blocked
+	if !allowGitConfig {
+		patterns = append(patterns, filepath.Join(cwd, ".git/config"))
+		patterns = append(patterns, "**/.git/config")
+	}
+
+	return patterns
+}