Kernel: Move Jail code to a new subdirectory

Kernel/Security/Jail.cpp

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2022-2023, Liav A. <liavalb@hotmail.co.il>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/IntrusiveList.h>
+#include <AK/Singleton.h>
+#include <Kernel/API/Jail.h>
+#include <Kernel/Process.h>
+#include <Kernel/Security/Jail.h>
+
+namespace Kernel {
+
+static Atomic<u64> s_jail_id;
+static Singleton<SpinlockProtected<Jail::List, LockRank::None>> s_all_instances {};
+
+static JailIndex generate_jail_id()
+{
+    return s_jail_id.fetch_add(1);
+}
+
+RefPtr<ProcessList> Jail::process_list()
+{
+    return m_process_list;
+}
+
+ErrorOr<NonnullRefPtr<Jail>> Jail::create(NonnullOwnPtr<KString> name, unsigned flags)
+{
+    RefPtr<ProcessList> jail_process_list;
+    if (flags & static_cast<unsigned>(JailIsolationFlags::PIDIsolation))
+        jail_process_list = TRY(ProcessList::create());
+
+    return s_all_instances->with([&](auto& list) -> ErrorOr<NonnullRefPtr<Jail>> {
+        auto jail = TRY(adopt_nonnull_ref_or_enomem(new (nothrow) Jail(move(name), generate_jail_id(), jail_process_list)));
+        list.append(jail);
+        return jail;
+    });
+}
+
+ErrorOr<void> Jail::for_each_when_process_is_not_jailed(Function<ErrorOr<void>(Jail const&)> callback)
+{
+    return Process::current().jail().with([&](auto const& my_jail) -> ErrorOr<void> {
+        // Note: If we are in a jail, don't reveal anything about the outside world,
+        // not even the fact that we are in which jail...
+        if (my_jail)
+            return {};
+        return s_all_instances->with([&](auto& list) -> ErrorOr<void> {
+            for (auto& jail : list) {
+                TRY(callback(jail));
+            }
+            return {};
+        });
+    });
+}
+
+RefPtr<Jail> Jail::find_by_index(JailIndex index)
+{
+    return s_all_instances->with([&](auto& list) -> RefPtr<Jail> {
+        for (auto& jail : list) {
+            if (jail.index() == index)
+                return jail;
+        }
+        return {};
+    });
+}
+
+Jail::Jail(NonnullOwnPtr<KString> name, JailIndex index, RefPtr<ProcessList> process_list)
+    : m_name(move(name))
+    , m_index(index)
+    , m_process_list(process_list)
+{
+}
+
+void Jail::detach(Badge<Process>)
+{
+    VERIFY(ref_count() > 0);
+    m_attach_count.with([&](auto& my_attach_count) {
+        VERIFY(my_attach_count > 0);
+        my_attach_count--;
+        if (my_attach_count == 0) {
+            m_list_node.remove();
+        }
+    });
+}
+
+}