Update drivers

library/vm.c

@@ -0,0 +1,114 @@
+/*
+	This file is part of Fennix Drivers.
+
+	Fennix Drivers is free software: you can redistribute it and/or
+	modify it under the terms of the GNU General Public License as
+	published by the Free Software Foundation, either version 3 of
+	the License, or (at your option) any later version.
+
+	Fennix Drivers is distributed in the hope that 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 Fennix Drivers. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <vm.h>
+
+int __strcmp(const char *l, const char *r)
+{
+	for (; *l == *r && *l; l++, r++)
+		;
+
+	return *(unsigned char *)l - *(unsigned char *)r;
+}
+
+void __cpuid(uint32_t Function,
+			 uint32_t *eax, uint32_t *ebx,
+			 uint32_t *ecx, uint32_t *edx)
+{
+	asmv("cpuid"
+		 : "=a"(*eax), "=b"(*ebx), "=c"(*ecx), "=d"(*edx)
+		 : "a"(Function));
+}
+
+bool __CheckHypervisorBit()
+{
+	uint32_t eax, ebx, ecx, edx;
+	__cpuid(0x1, &eax, &ebx, &ecx, &edx);
+	if (!(ecx & (1 << 31)))
+		return false; /* Hypervisor not detected */
+	return true;
+}
+
+bool __VMwareBackdoorHypervisors()
+{
+	const char hv[13] = {0};
+	uint32_t eax, ebx, ecx, edx;
+	__cpuid(0x40000000, &eax, &ebx, &ecx, &edx);
+
+	*(uint32_t *)hv = ebx;
+	*(uint32_t *)(hv + 4) = ecx;
+	*(uint32_t *)(hv + 8) = edx;
+
+	if (__strcmp(hv, "VMwareVMware") != 0 &&
+		__strcmp(hv, "KVMKVMKVM") != 0 &&
+		__strcmp(hv, "TCGTCGTCGTCG") != 0)
+	{
+		return false;
+	}
+	return true;
+}
+
+bool IsVMwareBackdoorAvailable()
+{
+	if (!__CheckHypervisorBit())
+		return false;
+
+	if (!__VMwareBackdoorHypervisors())
+		return false;
+
+	struct
+	{
+		union
+		{
+			uint32_t ax;
+			uint32_t magic;
+		};
+		union
+		{
+			uint32_t bx;
+			size_t size;
+		};
+		union
+		{
+			uint32_t cx;
+			uint16_t command;
+		};
+		union
+		{
+			uint32_t dx;
+			uint16_t port;
+		};
+		uint32_t si;
+		uint32_t di;
+	} cmd;
+
+	cmd.si = cmd.di = 0;
+	cmd.bx = ~0x564D5868;
+	cmd.command = 0xA;
+	cmd.magic = 0x564D5868;
+	cmd.port = 0x5658;
+
+	asmv("in %%dx, %0"
+		 : "+a"(cmd.ax), "+b"(cmd.bx),
+		   "+c"(cmd.cx), "+d"(cmd.dx),
+		   "+S"(cmd.si), "+D"(cmd.di));
+
+	if (cmd.bx != 0x564D5868 ||
+		cmd.ax == 0xFFFFFFFF)
+		return false;
+	return true;
+}