Add environment sanitization

internal/sandbox/sanitize_test.go

@@ -0,0 +1,156 @@
+package sandbox
+
+import (
+	"testing"
+)
+
+func TestIsDangerousEnvVar(t *testing.T) {
+	tests := []struct {
+		entry     string
+		dangerous bool
+	}{
+		// Linux LD_* variables
+		{"LD_PRELOAD=/tmp/evil.so", true},
+		{"LD_LIBRARY_PATH=/tmp", true},
+		{"LD_AUDIT=/tmp/audit.so", true},
+		{"LD_DEBUG=all", true},
+
+		// macOS DYLD_* variables
+		{"DYLD_INSERT_LIBRARIES=/tmp/evil.dylib", true},
+		{"DYLD_LIBRARY_PATH=/tmp", true},
+		{"DYLD_FRAMEWORK_PATH=/tmp", true},
+		{"DYLD_FORCE_FLAT_NAMESPACE=1", true},
+
+		// Safe variables
+		{"PATH=/usr/bin:/bin", false},
+		{"HOME=/home/user", false},
+		{"USER=user", false},
+		{"SHELL=/bin/bash", false},
+		{"HTTP_PROXY=http://localhost:8080", false},
+		{"HTTPS_PROXY=http://localhost:8080", false},
+
+		// Edge cases - variables that start with similar prefixes but aren't dangerous
+		{"LDFLAGS=-L/usr/lib", false}, // Not LD_ prefix
+		{"DISPLAY=:0", false},
+
+		// Empty and malformed
+		{"LD_PRELOAD", true}, // No value but still dangerous
+		{"", false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.entry, func(t *testing.T) {
+			got := isDangerousEnvVar(tt.entry)
+			if got != tt.dangerous {
+				t.Errorf("isDangerousEnvVar(%q) = %v, want %v", tt.entry, got, tt.dangerous)
+			}
+		})
+	}
+}
+
+func TestFilterDangerousEnv(t *testing.T) {
+	env := []string{
+		"PATH=/usr/bin:/bin",
+		"LD_PRELOAD=/tmp/evil.so",
+		"HOME=/home/user",
+		"DYLD_INSERT_LIBRARIES=/tmp/evil.dylib",
+		"HTTP_PROXY=http://localhost:8080",
+		"LD_LIBRARY_PATH=/tmp",
+	}
+
+	filtered := FilterDangerousEnv(env)
+
+	// Should have 3 safe vars
+	if len(filtered) != 3 {
+		t.Errorf("expected 3 safe vars, got %d: %v", len(filtered), filtered)
+	}
+
+	// Verify the safe vars are present
+	expected := map[string]bool{
+		"PATH=/usr/bin:/bin":               true,
+		"HOME=/home/user":                  true,
+		"HTTP_PROXY=http://localhost:8080": true,
+	}
+
+	for _, e := range filtered {
+		if !expected[e] {
+			t.Errorf("unexpected var in filtered env: %s", e)
+		}
+	}
+
+	// Verify dangerous vars are gone
+	for _, e := range filtered {
+		if isDangerousEnvVar(e) {
+			t.Errorf("dangerous var not filtered: %s", e)
+		}
+	}
+}
+
+func TestGetStrippedEnvVars(t *testing.T) {
+	env := []string{
+		"PATH=/usr/bin",
+		"LD_PRELOAD=/tmp/evil.so",
+		"DYLD_INSERT_LIBRARIES=/tmp/evil.dylib",
+		"HOME=/home/user",
+	}
+
+	stripped := GetStrippedEnvVars(env)
+
+	if len(stripped) != 2 {
+		t.Errorf("expected 2 stripped vars, got %d: %v", len(stripped), stripped)
+	}
+
+	// Should contain just the keys, not values
+	found := make(map[string]bool)
+	for _, s := range stripped {
+		found[s] = true
+	}
+
+	if !found["LD_PRELOAD"] {
+		t.Error("expected LD_PRELOAD to be in stripped list")
+	}
+	if !found["DYLD_INSERT_LIBRARIES"] {
+		t.Error("expected DYLD_INSERT_LIBRARIES to be in stripped list")
+	}
+}
+
+func TestFilterDangerousEnv_EmptyInput(t *testing.T) {
+	filtered := FilterDangerousEnv(nil)
+	if filtered == nil {
+		t.Error("expected non-nil slice for nil input")
+	}
+	if len(filtered) != 0 {
+		t.Errorf("expected empty slice, got %v", filtered)
+	}
+
+	filtered = FilterDangerousEnv([]string{})
+	if len(filtered) != 0 {
+		t.Errorf("expected empty slice, got %v", filtered)
+	}
+}
+
+func TestFilterDangerousEnv_AllDangerous(t *testing.T) {
+	env := []string{
+		"LD_PRELOAD=/tmp/evil.so",
+		"LD_LIBRARY_PATH=/tmp",
+		"DYLD_INSERT_LIBRARIES=/tmp/evil.dylib",
+	}
+
+	filtered := FilterDangerousEnv(env)
+	if len(filtered) != 0 {
+		t.Errorf("expected all vars to be filtered, got %v", filtered)
+	}
+}
+
+func TestFilterDangerousEnv_AllSafe(t *testing.T) {
+	env := []string{
+		"PATH=/usr/bin",
+		"HOME=/home/user",
+		"USER=test",
+	}
+
+	filtered := FilterDangerousEnv(env)
+	if len(filtered) != 3 {
+		t.Errorf("expected all 3 vars to pass through, got %d", len(filtered))
+	}
+}