Merge pull request #4 from 21pages/master

Cargo.toml

@@ -13,3 +13,7 @@ Get os native machine id without root permission.
 
 [target.'cfg(windows)'.dependencies]
 winreg = "0.11"
+
+[build-dependencies]
+cc = "1.0"
+bindgen = "0.59"

build.rs

@@ -0,0 +1,10 @@
+use cc::Build;
+
+fn main() {
+    println!("cargo:rerun-if-changed=src");
+    #[cfg(target_os = "windows")]
+    {
+        println!("cargo:rustc-link-lib=Kernel32");
+        Build::new().file("src/win.cpp").compile("machine-uid");
+    }
+}

src/lib.rs

@@ -155,13 +155,25 @@ mod machine_id {
 #[cfg(target_os = "windows")]
 pub mod machine_id {
     use std::error::Error;
-    use winreg::enums::HKEY_LOCAL_MACHINE;
+    use std::ffi::c_int;
+    use winreg::enums::{HKEY_LOCAL_MACHINE, KEY_READ, KEY_WOW64_64KEY};
     use winreg::RegKey;
 
+    extern "C" {
+        fn MachineUidIsWow64() -> c_int;
+    }
+
     /// Return machine id
     pub fn get_machine_id() -> Result<String, Box<dyn Error>> {
         let hklm = RegKey::predef(HKEY_LOCAL_MACHINE);
-        let crypto = hklm.open_subkey("SOFTWARE\\Microsoft\\Cryptography")?;
+
+        let flag = if unsafe { MachineUidIsWow64() == 1 } && cfg!(target_pointer_width = "32") {
+            KEY_READ | KEY_WOW64_64KEY
+        } else {
+            KEY_READ
+        };
+
+        let crypto = hklm.open_subkey_with_flags("SOFTWARE\\Microsoft\\Cryptography", flag)?;
         let id: String = crypto.get_value("MachineGuid")?;
 
         Ok(id.trim().to_string())

src/win.cpp

@@ -0,0 +1,29 @@
+#include <windows.h>
+#include <tchar.h>
+
+// https://learn.microsoft.com/en-us/windows/win32/api/wow64apiset/nf-wow64apiset-iswow64process
+
+typedef BOOL (WINAPI *LPFN_ISWOW64PROCESS) (HANDLE, PBOOL);
+
+static LPFN_ISWOW64PROCESS fnIsWow64Process;
+
+extern "C" BOOL MachineUidIsWow64()
+{
+    BOOL bIsWow64 = FALSE;
+
+    //IsWow64Process is not available on all supported versions of Windows.
+    //Use GetModuleHandle to get a handle to the DLL that contains the function
+    //and GetProcAddress to get a pointer to the function if available.
+
+    fnIsWow64Process = (LPFN_ISWOW64PROCESS) GetProcAddress(
+        GetModuleHandle(TEXT("kernel32")),"IsWow64Process");
+
+    if(NULL != fnIsWow64Process)
+    {
+        if (!fnIsWow64Process(GetCurrentProcess(),&bIsWow64))
+        {
+            //handle error
+        }
+    }
+    return bIsWow64;
+}