1 files changed, 74 insertions, 0 deletions
diff --git a/installer/fetcher/systeminfo.c b/installer/fetcher/systeminfo.c
new file mode 100644
index 00000000..f1f80e7f
--- /dev/null
+++ b/installer/fetcher/systeminfo.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2022 Jason A. Donenfeld. All Rights Reserved.
+ */
+
+#include "systeminfo.h"
+#include "version.h"
+#include <windows.h>
+#include <stdbool.h>
+#include <stdio.h>
+
+extern NTAPI __declspec(dllimport) void RtlGetNtVersionNumbers(DWORD *MajorVersion, DWORD *MinorVersion, DWORD *BuildNumber);
+
+const char *architecture(void)
+{
+	static const char *cached_arch;
+	HMODULE kernel32;
+	BOOL(WINAPI *IsWow64Process2)(HANDLE hProcess, USHORT *pProcessMachine, USHORT *pNativeMachine);
+	USHORT process_machine, native_machine;
+	BOOL is_wow64_process;
+
+	if (cached_arch)
+		return cached_arch;
+
+	kernel32 = GetModuleHandleA("kernel32.dll");
+	if (!kernel32)
+		return NULL;
+	*(FARPROC *)&IsWow64Process2 = GetProcAddress(kernel32, "IsWow64Process2");
+	if (IsWow64Process2) {
+		if (!IsWow64Process2(GetCurrentProcess(), &process_machine, &native_machine))
+			return NULL;
+		switch (native_machine) {
+		case IMAGE_FILE_MACHINE_I386:
+			return cached_arch = "x86";
+		case IMAGE_FILE_MACHINE_AMD64:
+			return cached_arch = "amd64";
+		case IMAGE_FILE_MACHINE_ARMNT:
+			return cached_arch = "arm";
+		case IMAGE_FILE_MACHINE_ARM64:
+			return cached_arch = "arm64";
+		}
+	} else {
+		if (!IsWow64Process(GetCurrentProcess(), &is_wow64_process))
+			return NULL;
+		return cached_arch = is_wow64_process ? "amd64" : "x86";
+	}
+	return NULL;
+}
+
+const char *useragent(void)
+{
+	static char useragent[0x200];
+	DWORD maj, min, build;
+
+	if (useragent[0])
+		return useragent;
+	RtlGetNtVersionNumbers(&maj, &min, &build);
+	_snprintf_s(useragent, sizeof(useragent), _TRUNCATE, "WireGuard-Fetcher/" VERSION_STR " (Windows %lu.%lu.%lu; %s)", maj, min, build & 0xffff, architecture());
+	return useragent;
+}
+
+bool is_win7(void)
+{
+	DWORD maj, min, build;
+	RtlGetNtVersionNumbers(&maj, &min, &build);
+	return maj == 6 && min == 1;
+}
+
+bool is_win8dotzero_or_below(void)
+{
+	DWORD maj, min, build;
+	RtlGetNtVersionNumbers(&maj, &min, &build);
+	return maj == 6 && min <= 2;
+}