1 files changed, 66 insertions, 0 deletions
diff --git a/src/lib/llharden/winprocess_sys.c b/src/lib/llharden/winprocess_sys.c
new file mode 100644
index 0000000000..a5f22c182b
--- /dev/null
+++ b/src/lib/llharden/winprocess_sys.c
@@ -0,0 +1,66 @@
+/* Copyright (c) 2018-2020, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file winprocess_sys.c
+ * \brief Subsystem object for windows process setup.
+ **/
+
+#include "orconfig.h"
+#include "lib/subsys/subsys.h"
+#include "lib/llharden/winprocess_sys.h"
+
+#include <stdbool.h>
+#include <stddef.h>
+
+#ifdef _WIN32
+#include <windows.h>
+
+#define WINPROCESS_SYS_ENABLED true
+
+static int
+subsys_winprocess_initialize(void)
+{
+#ifndef HeapEnableTerminationOnCorruption
+#define HeapEnableTerminationOnCorruption 1
+#endif
+
+  /* On heap corruption, just give up; don't try to play along. */
+  HeapSetInformation(NULL, HeapEnableTerminationOnCorruption, NULL, 0);
+
+  /* SetProcessDEPPolicy is only supported on 32-bit Windows.
+   * (On 64-bit Windows it always fails, and some compilers don't like the
+   * PSETDEP cast.)
+   * 32-bit Windows defines _WIN32.
+   * 64-bit Windows defines _WIN32 and _WIN64. */
+#ifndef _WIN64
+  /* Call SetProcessDEPPolicy to permanently enable DEP.
+     The function will not resolve on earlier versions of Windows,
+     and failure is not dangerous. */
+  HMODULE hMod = GetModuleHandleA("Kernel32.dll");
+  if (hMod) {
+    typedef BOOL (WINAPI *PSETDEP)(DWORD);
+    PSETDEP setdeppolicy = (PSETDEP)GetProcAddress(hMod,
+                           "SetProcessDEPPolicy");
+    if (setdeppolicy) {
+      /* PROCESS_DEP_ENABLE | PROCESS_DEP_DISABLE_ATL_THUNK_EMULATION */
+      setdeppolicy(3);
+    }
+  }
+#endif /* !defined(_WIN64) */
+
+  return 0;
+}
+#else /* !defined(_WIN32) */
+#define WINPROCESS_SYS_ENABLED false
+#define subsys_winprocess_initialize NULL
+#endif /* defined(_WIN32) */
+
+const subsys_fns_t sys_winprocess = {
+  .name = "winprocess",
+  /* HeapEnableTerminationOnCorruption and setdeppolicy() are security
+   * features, we want them to run first. */
+  .level = -100,
+  .supported = WINPROCESS_SYS_ENABLED,
+  .initialize = subsys_winprocess_initialize,
+};