os: update os namespace for 15.0.0, loader/ro: update to use csrng, spl: bump max sessions

stratosphere/ro/source/impl/ro_random.cpp

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 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 "ro_random.hpp"
+
+namespace ams::ro::impl {
+
+    u64 GenerateSecureRandom(u64 max) {
+        /* Generate a cryptographically random number. */
+        u64 rand;
+        crypto::GenerateCryptographicallyRandomBytes(std::addressof(rand), sizeof(rand));
+
+        /* Coerce into range. */
+        return rand % (max + 1);
+    }
+
+}