From a43e4f1593d10d7517e21458ce17f1789e6a1d42 Mon Sep 17 00:00:00 2001
From: Alex <enderice2@users.noreply.github.com>
Date: Tue, 20 Dec 2022 06:55:34 +0200
Subject: [PATCH] Updated the random number generator

---
 Core/Random.cpp  | 139 +++++++++++++++++++++++++++++++++++++++++++++--
 include/rand.hpp |   2 +-
 2 files changed, 135 insertions(+), 6 deletions(-)

diff --git a/Core/Random.cpp b/Core/Random.cpp
index 8e05863..53621c0 100644
--- a/Core/Random.cpp
+++ b/Core/Random.cpp
@@ -1,4 +1,5 @@
 #include <rand.hpp>
+#include <cpu.hpp>
 
 namespace Random
 {
@@ -6,22 +7,150 @@ namespace Random
 
     uint16_t rand16()
     {
+        int RDRANDFlag = 0;
+        if (strcmp(CPU::Vendor(), x86_CPUID_VENDOR_AMD) == 0)
+        {
+#if defined(__amd64__)
+            CPU::x64::AMD::CPUID0x1 cpuid1amd;
+#elif defined(__i386__)
+            CPU::x32::AMD::CPUID0x1 cpuid1amd;
+#endif
+#if defined(__amd64__) || defined(__i386__)
+            asmv("cpuid"
+                 : "=a"(cpuid1amd.EAX.raw), "=b"(cpuid1amd.EBX.raw), "=c"(cpuid1amd.ECX.raw), "=d"(cpuid1amd.EDX.raw)
+                 : "a"(0x1));
+#endif
+            RDRANDFlag = cpuid1amd.ECX.RDRAND;
+        }
+        if (strcmp(CPU::Vendor(), x86_CPUID_VENDOR_INTEL) == 0)
+        {
+#if defined(__amd64__)
+            CPU::x64::Intel::CPUID0x1 cpuid1intel;
+#elif defined(__i386__)
+            CPU::x32::Intel::CPUID0x1 cpuid1intel;
+#endif
+#if defined(__amd64__) || defined(__i386__)
+            asmv("cpuid"
+                 : "=a"(cpuid1intel.EAX.raw), "=b"(cpuid1intel.EBX.raw), "=c"(cpuid1intel.ECX.raw), "=d"(cpuid1intel.EDX.raw)
+                 : "a"(0x1));
+#endif
+            RDRANDFlag = cpuid1intel.ECX.RDRAND;
+        }
+
+        if (strcmp(CPU::Hypervisor(), x86_CPUID_VENDOR_TCG) == 0)
+            RDRANDFlag = 0;
+
+#if defined(__amd64__) || defined(__i386__)
+        if (RDRANDFlag)
+        {
+            uint16_t RDRANDValue = 0;
+            asmv("1: rdrand %0; jnc 1b"
+                 : "=r"(RDRANDValue));
+            return RDRANDValue;
+        }
+#endif
+
         Seed = Seed * 1103515245 + 12345;
         return (uint16_t)(Seed / 65536) % __UINT16_MAX__;
     }
 
     uint32_t rand32()
     {
+        int RDRANDFlag = 0;
+        if (strcmp(CPU::Vendor(), x86_CPUID_VENDOR_AMD) == 0)
+        {
+#if defined(__amd64__)
+            CPU::x64::AMD::CPUID0x1 cpuid1amd;
+#elif defined(__i386__)
+            CPU::x32::AMD::CPUID0x1 cpuid1amd;
+#endif
+#if defined(__amd64__) || defined(__i386__)
+            asmv("cpuid"
+                 : "=a"(cpuid1amd.EAX.raw), "=b"(cpuid1amd.EBX.raw), "=c"(cpuid1amd.ECX.raw), "=d"(cpuid1amd.EDX.raw)
+                 : "a"(0x1));
+#endif
+            RDRANDFlag = cpuid1amd.ECX.RDRAND;
+        }
+        if (strcmp(CPU::Vendor(), x86_CPUID_VENDOR_INTEL) == 0)
+        {
+#if defined(__amd64__)
+            CPU::x64::Intel::CPUID0x1 cpuid1intel;
+#elif defined(__i386__)
+            CPU::x32::Intel::CPUID0x1 cpuid1intel;
+#endif
+#if defined(__amd64__) || defined(__i386__)
+            asmv("cpuid"
+                 : "=a"(cpuid1intel.EAX.raw), "=b"(cpuid1intel.EBX.raw), "=c"(cpuid1intel.ECX.raw), "=d"(cpuid1intel.EDX.raw)
+                 : "a"(0x1));
+#endif
+            RDRANDFlag = cpuid1intel.ECX.RDRAND;
+        }
+
+        if (strcmp(CPU::Hypervisor(), x86_CPUID_VENDOR_TCG) == 0)
+            RDRANDFlag = 0;
+
+#if defined(__amd64__) || defined(__i386__)
+        if (RDRANDFlag)
+        {
+            uint32_t RDRANDValue = 0;
+            asmv("1: rdrand %0; jnc 1b"
+                 : "=r"(RDRANDValue));
+            return RDRANDValue;
+        }
+#endif
+
         Seed = Seed * 1103515245 + 12345;
-        return (uint32_t)(Seed / 65536) % __UINT32_MAX__;
+        return (uint32_t)(Seed / 65536) % __UINT16_MAX__;
     }
 
     uint64_t rand64()
     {
+        int RDRANDFlag = 0;
+        if (strcmp(CPU::Vendor(), x86_CPUID_VENDOR_AMD) == 0)
+        {
+#if defined(__amd64__)
+            CPU::x64::AMD::CPUID0x1 cpuid1amd;
+#elif defined(__i386__)
+            CPU::x32::AMD::CPUID0x1 cpuid1amd;
+#endif
+#if defined(__amd64__) || defined(__i386__)
+            asmv("cpuid"
+                 : "=a"(cpuid1amd.EAX.raw), "=b"(cpuid1amd.EBX.raw), "=c"(cpuid1amd.ECX.raw), "=d"(cpuid1amd.EDX.raw)
+                 : "a"(0x1));
+#endif
+            RDRANDFlag = cpuid1amd.ECX.RDRAND;
+        }
+        if (strcmp(CPU::Vendor(), x86_CPUID_VENDOR_INTEL) == 0)
+        {
+#if defined(__amd64__)
+            CPU::x64::Intel::CPUID0x1 cpuid1intel;
+#elif defined(__i386__)
+            CPU::x32::Intel::CPUID0x1 cpuid1intel;
+#endif
+#if defined(__amd64__) || defined(__i386__)
+            asmv("cpuid"
+                 : "=a"(cpuid1intel.EAX.raw), "=b"(cpuid1intel.EBX.raw), "=c"(cpuid1intel.ECX.raw), "=d"(cpuid1intel.EDX.raw)
+                 : "a"(0x1));
+#endif
+            RDRANDFlag = cpuid1intel.ECX.RDRAND;
+        }
+
+        if (strcmp(CPU::Hypervisor(), x86_CPUID_VENDOR_TCG) == 0)
+            RDRANDFlag = 0;
+
+#if defined(__amd64__) || defined(__i386__)
+        if (RDRANDFlag)
+        {
+            uint64_t RDRANDValue = 0;
+            asmv("1: rdrand %0; jnc 1b"
+                 : "=r"(RDRANDValue));
+            return RDRANDValue;
+        }
+#endif
+
         Seed = Seed * 1103515245 + 12345;
-        return (uint64_t)(Seed / 65536) % __UINT64_MAX__;
+        return (uint64_t)(Seed / 65536) % __UINT16_MAX__;
     }
 
-    void changeseed(uint64_t CustomSeed) { Seed = CustomSeed; }
-
-}
\ No newline at end of file
+    void ChangeSeed(uint64_t CustomSeed) { Seed = CustomSeed; }
+}
diff --git a/include/rand.hpp b/include/rand.hpp
index 81cff9e..715851c 100644
--- a/include/rand.hpp
+++ b/include/rand.hpp
@@ -8,7 +8,7 @@ namespace Random
     uint16_t rand16();
     uint32_t rand32();
     uint64_t rand64();
-    void changeseed(uint64_t CustomSeed);
+    void ChangeSeed(uint64_t CustomSeed);
 }
 
 #endif // !__FENNIX_KERNEL_RANDOM_H__