From be54052b6df81cb17fa855c64eff6ad7190ab5c5 Mon Sep 17 00:00:00 2001
From: TuxSH <tuxsh@sfr.fr>
Date: Sat, 7 May 2016 23:40:02 +0200
Subject: [PATCH] Make 3ds_injector able to be bigger than the official loader
 module (max. 25KB on O3DS due to memory limitations). Thanks @mid-kid for the
 idea.

---
 source/firm.c | 27 +++++++++++----------------
 source/firm.h |  2 +-
 2 files changed, 12 insertions(+), 17 deletions(-)

diff --git a/source/firm.c b/source/firm.c
index 01579fa..0eea686 100755
--- a/source/firm.c
+++ b/source/firm.c
@@ -283,8 +283,8 @@ static inline void patchNativeFirm(u32 nandType, u32 emuHeader, u32 a9lhMode)
     *(u16 *)sigOffset2 = sigPatch[0];
     *((u16 *)sigOffset2 + 1) = sigPatch[1];
 
-    //Replace the FIRM loader with the injector
-    injectLoader();
+    //Replace the FIRM loader with the injector while copying section0
+    copySection0AndInjectLoader();
 }
 
 static inline void patchEmuNAND(u8 *arm9Section, u8 *proc9Offset, u32 emuHeader)
@@ -342,21 +342,16 @@ static inline void patchReboots(u8 *arm9Section, u8 *proc9Offset)
     *pos_fopen = fOpenOffset;
 }
 
-static inline void injectLoader(void)
+static inline void copySection0AndInjectLoader(void)
 {
     u32 loaderSize;
-
-    void *loaderOffset = getLoader((u8 *)firm + section[0].offset, section[0].size, &loaderSize);
-
-    //Check that the injector CXI isn't larger than the original
-    if((u32)injector_size <= loaderSize)
-    {
-        memcpy(loaderOffset, injector, injector_size);
-
-        //Patch content size and ExeFS size to match the repaced loader's ones
-        *((u32 *)loaderOffset + 0x41) = loaderSize / 0x200;
-        *((u32 *)loaderOffset + 0x69) = loaderSize / 0x200 - 5;
-    }
+    u8 *arm11Section0 = (u8 *)firm + section[0].offset;
+    u32 injectorOffset = (u8 *)getLoader((u8 *)firm + section[0].offset, section[0].size, &loaderSize) - arm11Section0;
+    u32 remaining = section[0].size - (injectorOffset + loaderSize);
+    
+    memcpy(section[0].address, arm11Section0, injectorOffset);
+    memcpy(section[0].address + injectorOffset, injector, injector_size);
+    memcpy(section[0].address + injectorOffset + injector_size, arm11Section0 + section[0].size - remaining, remaining);
 }
 
 static inline void patchLegacyFirm(u32 firmType)
@@ -441,7 +436,7 @@ static void patchFirmWrites(u8 *arm9Section, u32 mode)
 static inline void launchFirm(u32 bootType)
 {
     //Copy FIRM sections to respective memory locations
-    for(u32 i = 0; i < 4 && section[i].size; i++)
+    for(u32 i = 1; i < 4 && section[i].size; i++)
         memcpy(section[i].address, (u8 *)firm + section[i].offset, section[i].size);
 
     //Determine the ARM11 entry to use
diff --git a/source/firm.h b/source/firm.h
index 3786460..e8a72bf 100644
--- a/source/firm.h
+++ b/source/firm.h
@@ -40,7 +40,7 @@ static inline void loadFirm(u32 firmType, u32 externalFirm);
 static inline void patchNativeFirm(u32 nandType, u32 emuHeader, u32 a9lhMode);
 static inline void patchEmuNAND(u8 *arm9Section, u8 *proc9Offset, u32 emuHeader);
 static inline void patchReboots(u8 *arm9Section, u8 *proc9Offset);
-static inline void injectLoader(void);
+static inline void copySection0AndInjectLoader(void);
 static inline void patchLegacyFirm(u32 firmType);
 static inline void patchSafeFirm(void);
 static void patchFirmWrites(u8 *arm9Section, u32 mode);