Added support for auto process exit when child ends

injector/src/lib.rs

@@ -8,14 +8,12 @@ use log::{debug, error, info, trace};
 use path_clean::PathClean;
 use serde::{Deserialize, Serialize};
 use windows::core::{PSTR, s};
-use windows::Win32::Foundation::{CloseHandle, GetLastError, HANDLE};
+use windows::Win32::Foundation::{CloseHandle, GetLastError, HANDLE, NTSTATUS};
 use windows::Win32::System::Diagnostics::Debug::WriteProcessMemory;
 use windows::Win32::System::LibraryLoader::{GetModuleHandleA, GetProcAddress};
 use windows::Win32::System::Memory::{MEM_COMMIT, MEM_RELEASE, MEM_RESERVE, PAGE_READWRITE,
                                      VirtualAllocEx, VirtualFreeEx};
-use windows::Win32::System::Threading::{CREATE_SUSPENDED, CreateProcessA, CreateRemoteThread, 
-                                        PROCESS_INFORMATION, ResumeThread, STARTUPINFOA, 
-                                        TerminateProcess, TerminateThread, WaitForSingleObject};
+use windows::Win32::System::Threading::{CREATE_SUSPENDED, CreateProcessA, CreateRemoteThread, GetExitCodeProcess, PROCESS_INFORMATION, ResumeThread, STARTUPINFOA, TerminateProcess, TerminateThread, WaitForSingleObject};
 
 type FarProcUnwrapped = unsafe extern "system" fn() -> isize;
 type LPThreadStartRoutine = unsafe extern "system" fn(param: *mut c_void) -> u32;
@@ -258,11 +256,30 @@ pub fn spawn_process<'a>(launcher: Launcher, env: Environment) -> Result<Context
         debug!("Injection of dll: {inject} succeeded!");
     }
 
-    unsafe {
-        ResumeThread(proc_info.hThread);
-        CloseHandle(proc_info.hThread)?;
-        CloseHandle(proc_info.hProcess)?;
-    }
+    unsafe { ResumeThread(proc_info.hThread); }
     info!("Successful injection finished");
     Ok(Context { proc_info, environment })
 }
+
+pub fn is_process_running(proc_info: PROCESS_INFORMATION) -> bool {
+    let mut exit_code = 0u32;
+    let result = unsafe { GetExitCodeProcess(proc_info.hProcess, &mut exit_code) };
+    match result {
+        Ok(_) => {
+            match NTSTATUS(exit_code as i32) {
+                windows::Win32::Foundation::STILL_ACTIVE => true,
+                _ => {
+                    unsafe {
+                        CloseHandle(proc_info.hThread).unwrap();
+                        CloseHandle(proc_info.hProcess).unwrap();
+                    }
+                    false
+                }
+            }
+        }
+        Err(err) => {
+            error!("Error while getting exit result: {err:?}");
+            true
+        }
+    }
+}

launcher/src/main.rs

@@ -1,5 +1,5 @@
 use clap::Parser;
-use log::{error, trace};
+use log::{error, info, trace};
 use serde::{Deserialize, Serialize};
 
 #[derive(Serialize, Deserialize, Debug)]
@@ -73,7 +73,7 @@ fn run(config_file: String) -> Result<injector::Context, Error> {
     trace!("{:?}", configuration);
     Ok(injector::spawn_process(
         configuration.launcher,
-        configuration.environment.unwrap_or_default()
+        configuration.environment.unwrap_or_default(),
     )?)
 }
 
@@ -84,11 +84,14 @@ fn main() {
         .init();
 
     match run(args.config_file) {
-        Ok(_context) => {
+        Ok(context) => {
             // Since environment pointer has to outlive the process, here we can do several things,
             // either we join the thread of the process, or we just wait
-            std::thread::sleep(std::time::Duration::from_secs(u64::MAX))
-        },
+            while injector::is_process_running(context.proc_info) {
+                std::thread::sleep(std::time::Duration::from_secs(1))
+            }
+            info!("Application exited");
+        }
         Err(err) => error!("{}", err.to_string())
     }
 }