From 99d7d69b751bc748a55967b09125211899b6ac85 Mon Sep 17 00:00:00 2001
From: Akash Mozumdar <akashmozumdar@gmail.com>
Date: Tue, 12 Feb 2019 23:54:46 -0500
Subject: [PATCH] more mono hooks

---
 vnrhook/engine/engine.cc       | 33 +++++++++++++++++++++++++++++++++
 vnrhook/engine/mono/funcinfo.h | 10 +++++++---
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/vnrhook/engine/engine.cc b/vnrhook/engine/engine.cc
index 8f26717..3c4375a 100644
--- a/vnrhook/engine/engine.cc
+++ b/vnrhook/engine/engine.cc
@@ -16593,6 +16593,38 @@ bool InsertMonoHook()
 	return found;
 }
 
+void InsertMonoHook3()
+{
+	const BYTE bytes[] = { // Characteristic pattern of System.String.CharCopy in Venus Blood Lagoon https://vndb.org/v23125 and レイジングループ
+		// Cheat Engine 'Dissect Mono' feature is very useful in finding Mono hooks. Gives functions to look at in the stacktrace
+		0x55, // push ebp
+		0x8b, 0xec, // mov ebp,esp
+		0x53, // push ebx
+		0x57, // push edi
+		0x56, // push esi
+		0x83, 0xec, 0x0c, // sub esp,0x0c
+		0x8b, 0x5d, 0x08, // mov ebx,[ebp+0x08] ; wchar_t*
+		0x8b, 0x75, 0x0c, // mov esi,[ebp+0x0c] ; length
+		0x8b, 0x7d, 0x10, // mov edi,[ebp+0x10] ; ?
+		0x8b, 0xc3, // mov eax,ebx
+		0x0b, 0xc6, // or eax,esi
+		0x25, 0x03, 0x00, 0x00, 0x00, // and eax,0x03
+		0x85, 0xc0, // test eax,eax
+		0x0f, 0x84, XX4, // je ??
+		0x8b, 0xc3, // mov eax,ebx
+		0x25, 0x02, 0x00, 0x00, 0x00 // and eax,0x02
+	};
+	for (auto addr : Util::SearchMemory(bytes, sizeof(bytes), PAGE_EXECUTE_READWRITE))
+	{
+		HookParam hp = {};
+		hp.address = addr;
+		hp.type = USING_UNICODE | USING_STRING;
+		hp.offset = 8;
+		hp.length_offset = 3;
+		NewHook(hp, "Mono3");
+	}
+}
+
 /** jichi 12/26/2014 Mono
  *  Sample game: [141226] ハ�レ�めいと
  */
@@ -16632,6 +16664,7 @@ bool InsertMonoHooks()
 
   InsertBaldrHook(); // Artikash 8/28/2018: insert for all mono games: maybe itll work for more than baldr sky zero?
   InsertMonoHook(); // Artikash 10/20/2018: dunno why this was removed, works for some stuff so readd
+  InsertMonoHook3();
   bool ret = false;
 
   // mono_unichar2* mono_string_to_utf16       (MonoString *s);
diff --git a/vnrhook/engine/mono/funcinfo.h b/vnrhook/engine/mono/funcinfo.h
index 6a4672b..143f0a5 100644
--- a/vnrhook/engine/mono/funcinfo.h
+++ b/vnrhook/engine/mono/funcinfo.h
@@ -33,10 +33,10 @@
 // gchar*         mono_unicode_to_external   (const gunichar2 *uni);
 // gchar*         mono_utf8_from_external    (const gchar *in);
 
-struct MonoFunction {
+struct MonoFunction { // argument indices start from 0 for SpecialHookMonoString, otherwise 1
   const char *functionName;
-  size_t textIndex; // argument index, starting from 0
-  size_t lengthIndex; // argument index, start from 0
+  size_t textIndex; // argument index
+  short lengthIndex; // argument index
   unsigned long hookType; // HookParam type
   void *text_fun; // HookParam::text_fun_t
 };
@@ -47,13 +47,17 @@ struct MonoFunction {
   , { "mono_string_to_utf16", 0, 0, USING_UNICODE|NO_CONTEXT, SpecialHookMonoString } \
   , { "mono_string_intern", 0, 0, USING_UNICODE|NO_CONTEXT, SpecialHookMonoString } \
   , { "mono_string_is_interned", 0, 0, USING_UNICODE|NO_CONTEXT, SpecialHookMonoString } \
+  , { "mono_marshal_string_to_utf16", 0, 0, USING_UNICODE|NO_CONTEXT, SpecialHookMonoString } \
   , { "mono_string_hash", 0, 0, USING_UNICODE, SpecialHookMonoString } \
+  , { "mono_string_chars", 0, 0, USING_UNICODE, SpecialHookMonoString } \
+  , { "mono_string_length", 0, 0, USING_UNICODE, SpecialHookMonoString } \
   , { "mono_utf8_from_external", 1, 0, USING_STRING|USING_UTF8, nullptr } \
   , { "mono_string_from_utf16", 1, 0, USING_UNICODE, nullptr } \
   , { "mono_string_new_utf16", 2, 3, USING_UNICODE, nullptr } \
   , { "mono_unicode_from_external", 1, 0, USING_UNICODE, nullptr } \
   , { "mono_unicode_to_external", 1, 0, USING_UNICODE, nullptr } \
   , { "mono_string_new", 2, 0, USING_STRING|USING_UTF8, nullptr } \
+  , { "mono_string_new_len", 2, 3, USING_STRING|USING_UTF8, nullptr } \
   , { "mono_string_new_wrapper", 1, 0, USING_STRING|USING_UTF8, nullptr }
 
 // EOF