os: add rngmanager

libraries/libstratosphere/source/os/impl/os_resource_manager.hpp

@@ -15,18 +15,21 @@
  */
 #pragma once
 #include <stratosphere.hpp>
+#include "os_rng_manager_impl.hpp"
 #include "os_tick_manager_impl.hpp"
 
 namespace ams::os::impl {
 
     class OsResourceManager {
         private:
+            RngManager  rng_manager{};
             /* TODO */
             TickManager tick_manager{};
             /* TODO */
         public:
             constexpr OsResourceManager() = default;
 
+            constexpr ALWAYS_INLINE RngManager &GetRngManager() { return this->rng_manager; }
             constexpr ALWAYS_INLINE TickManager &GetTickManager() { return this->tick_manager; }
     };
 

libraries/libstratosphere/source/os/impl/os_rng_manager.hpp

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+#include <stratosphere.hpp>
+
+namespace ams::os::impl {
+
+    ALWAYS_INLINE RngManager &GetRngManager() {
+        return GetResourceManager().GetRngManager();
+    }
+
+}

libraries/libstratosphere/source/os/impl/os_rng_manager_impl.cpp

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stratosphere.hpp>
+#include "os_rng_manager_impl.hpp"
+
+namespace ams::os::impl {
+
+    u64 RngManager::GenerateRandomU64() {
+        std::scoped_lock lk(this->lock);
+
+        if (AMS_UNLIKELY(!this->initialized)) {
+            this->Initialize();
+        }
+
+        return this->mt.GenerateRandomU64();
+    }
+
+}

libraries/libstratosphere/source/os/impl/os_rng_manager_impl.hpp

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+#include <stratosphere.hpp>
+
+namespace ams::os::impl {
+
+    class RngManager {
+        private:
+            util::TinyMT mt;
+            os::Mutex lock;
+            bool initialized;
+        private:
+            void Initialize();
+        public:
+            constexpr RngManager() : mt(), lock(), initialized() { /* ... */ }
+        public:
+            u64 GenerateRandomU64();
+    };
+
+}

libraries/libstratosphere/source/os/impl/os_rng_manager_impl.os.horizon.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stratosphere.hpp>
+#include "os_rng_manager_impl.hpp"
+
+namespace ams::os::impl {
+
+    void RngManager::Initialize() {
+        /* Retrieve entropy from kernel. */
+        u32 seed[4];
+        static_assert(util::size(seed) == util::TinyMT::NumStateWords);
+
+        /* Nintendo does not check the result of these invocations, but we will for safety. */
+        /* Nintendo uses entropy values 0, 1 to seed the public TinyMT random, and values */
+        /* 2, 3 to seed os::detail::RngManager's private TinyMT random. */
+        R_ABORT_UNLESS(svcGetInfo(reinterpret_cast<u64 *>(&seed[0]), InfoType_RandomEntropy, INVALID_HANDLE, 2));
+        R_ABORT_UNLESS(svcGetInfo(reinterpret_cast<u64 *>(&seed[2]), InfoType_RandomEntropy, INVALID_HANDLE, 3));
+
+        this->mt.Initialize(seed, util::size(seed));
+
+        /* Note that we've initialized. */
+        this->initialized = true;
+    }
+
+}

libraries/libstratosphere/source/os/os_random.cpp

@@ -42,7 +42,7 @@ namespace ams::os {
     void GenerateRandomBytes(void *dst, size_t size) {
         std::scoped_lock lk(g_random_mutex);
 
-        if (!g_initialized_random) {
+        if (AMS_UNLIKELY(!g_initialized_random)) {
             impl::InitializeRandomImpl(&g_random);
             g_initialized_random = true;
         }