From a68406e84c28b2dc6e3cf8c5a0b8da25d69f98a8 Mon Sep 17 00:00:00 2001
From: djp952 <djp952@gmail.com>
Date: Mon, 8 Jul 2019 11:43:27 -0400
Subject: [PATCH] Use RtlGenRandom when available to elminiate TLS and heap
 leaks

---
 hdhomerun_os_windows.c | 26 ++++----------------------
 hdhomerun_os_windows.h |  4 ++++
 2 files changed, 8 insertions(+), 22 deletions(-)

diff --git a/hdhomerun_os_windows.c b/hdhomerun_os_windows.c
index ea65945..ffc1d07 100644
--- a/hdhomerun_os_windows.c
+++ b/hdhomerun_os_windows.c
@@ -20,34 +20,16 @@
 
 #include "hdhomerun.h"
 
-#if defined(_WINRT)
 uint32_t random_get32(void)
 {
-	return (uint32_t)getcurrenttime();
-}
-#else
-uint32_t random_get32(void)
-{
-	static DWORD random_get32_context_tls = 0xFFFFFFFF;
-	if (random_get32_context_tls == 0xFFFFFFFF) {
-		random_get32_context_tls = TlsAlloc();
-	}
+	uint32_t Result = (uint32_t)getcurrenttime();
 
-	HCRYPTPROV *phProv = (HCRYPTPROV *)TlsGetValue(random_get32_context_tls);
-	if (!phProv) {
-		phProv = (HCRYPTPROV *)calloc(1, sizeof(HCRYPTPROV));
-		CryptAcquireContext(phProv, 0, 0, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT);
-		TlsSetValue(random_get32_context_tls, phProv);
-	}
-
-	uint32_t Result;
-	if (!CryptGenRandom(*phProv, sizeof(Result), (BYTE *)&Result)) {
-		return (uint32_t)getcurrenttime();
-	}
+#if defined(RtlGenRandom)
+	RtlGenRandom(&Result, sizeof(Result));
+#endif
 
 	return Result;
 }
-#endif
 
 uint64_t getcurrenttime(void)
 {
diff --git a/hdhomerun_os_windows.h b/hdhomerun_os_windows.h
index 62900e7..102e51f 100644
--- a/hdhomerun_os_windows.h
+++ b/hdhomerun_os_windows.h
@@ -46,6 +46,10 @@
 #include <time.h>
 #include <sys/types.h>
 
+#define SystemFunction036 NTAPI SystemFunction036
+#include <ntsecapi.h>
+#undef SystemFunction036
+
 #ifdef LIBHDHOMERUN_DLLEXPORT
 #define LIBHDHOMERUN_API __declspec(dllexport)
 #endif