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Luma3DS-3GX/source/firm.c

503 lines
15 KiB
C
Executable File

/*
* firm.c
*/
#include "firm.h"
#include "config.h"
#include "utils.h"
#include "fs.h"
#include "patches.h"
#include "memory.h"
#include "emunand.h"
#include "crypto.h"
#include "exceptions.h"
#include "draw.h"
#include "screeninit.h"
#include "buttons.h"
#include "../build/patches.h"
static firmHeader *const firm = (firmHeader *)0x24000000;
static const firmSectionHeader *section;
u32 config,
console,
firmSource,
emuOffset;
static inline void patchExceptionHandlersInstall(u8 *arm9Section)
{
static const u8 pattern[] = {
0x18, 0x10, 0x80, 0xE5,
0x10, 0x10, 0x80, 0xE5,
0x20, 0x10, 0x80, 0xE5,
0x28, 0x10, 0x80, 0xE5,
}; //i.e when it stores ldr pc, [pc, #-4]
u32* off = (u32 *)(memsearch(arm9Section, pattern, section[2].size, sizeof(pattern)));
if(off == NULL) return;
off += sizeof(pattern)/4;
u32 r0 = 0x08000000;
for(; *off != 0xE3A01040; off++) //until mov r1, #0x40
{
if((*off >> 26) != 0x39 || ((*off >> 16) & 0xf) != 0 || ((*off >> 25) & 1) != 0 || ((*off >> 20) & 5) != 0)
continue; //discard everything that's not str rX, [r0, #imm](!)
int rD = (*off >> 12) & 0xf;
int offset = (*off & 0xfff) * ((((*off >> 23) & 1) == 0) ? -1 : 1);
int writeback = (*off >> 21) & 1, pre = (*off >> 24) & 1;
u32 addr = r0 + ((pre || !writeback) ? offset : 0);
if(addr != 0x08000014 && addr != 0x08000004)
*off = 0xE1A00000; //nop
else
*off = 0xE5800000 | (rD << 12) | (addr & 0xfff); //preserve IRQ and svc handlers
if(!pre) addr += offset;
if(writeback) r0 = addr;
}
}
void main(void)
{
u32 bootType,
firmType,
nandType,
a9lhMode,
updatedSys,
needConfig,
newConfig,
emuHeader;
//Detect the console being used
console = PDN_MPCORE_CFG == 7;
//Mount filesystems. CTRNAND will be mounted only if/when needed
mountFs();
const char configPath[] = "/luma/config.bin";
//Attempt to read the configuration file
needConfig = fileRead(&config, configPath) ? 1 : 2;
//Determine if this is a firmlaunch boot
if(*(vu8 *)0x23F00005)
{
if(needConfig == 2) mcuReboot();
bootType = 1;
//'0' = NATIVE_FIRM, '1' = TWL_FIRM, '2' = AGB_FIRM
firmType = *(vu8 *)0x23F00009 == '3' ? 3 : *(vu8 *)0x23F00005 - '0';
nandType = BOOTCONFIG(0, 3);
firmSource = BOOTCONFIG(2, 1);
a9lhMode = BOOTCONFIG(3, 1);
updatedSys = a9lhMode && CONFIG(1);
}
else
{
//Get pressed buttons
u32 pressed = HID_PAD;
//If no configuration file exists or SELECT is held, load configuration menu
if(needConfig == 2 || (pressed & BUTTON_SELECT))
configureCFW(configPath);
u32 devMode = CONFIG(5);
if(devMode)
{
detectAndProcessExceptionDumps();
installArm9Handlers();
}
bootType = 0;
firmType = 0;
//Determine if booting with A9LH
u32 a9lhBoot = !PDN_SPI_CNT;
//Determine if A9LH is installed and the user has an updated sysNAND
if(a9lhBoot || CONFIG(2))
{
a9lhMode = 1;
updatedSys = CONFIG(1);
}
else
{
a9lhMode = 0;
updatedSys = 0;
}
newConfig = a9lhMode << 3;
if(a9lhBoot)
{
//Retrieve the last booted FIRM
u32 previousFirm = CFG_BOOTENV;
//If it's a MCU reboot, try to force boot options
if(previousFirm)
{
//Always force a sysNAND boot when quitting AGB_FIRM
if(previousFirm == 7)
{
nandType = 0;
firmSource = updatedSys ? 0 : BOOTCONFIG(2, 1);
needConfig--;
//Flag to prevent multiple boot options-forcing
newConfig |= 1 << 4;
}
/* Else, force the last used boot options unless a payload button or A/L/R are pressed
or the no-forcing flag is set */
else if(!(pressed & OVERRIDE_BUTTONS) && !BOOTCONFIG(4, 1))
{
nandType = BOOTCONFIG(0, 3);
firmSource = BOOTCONFIG(2, 1);
needConfig--;
}
}
//If the SAFE MODE combo is held, force a sysNAND boot
else if(pressed == SAFE_MODE)
{
a9lhMode++;
nandType = 0;
firmSource = 0;
needConfig--;
}
}
//Boot options aren't being forced
if(needConfig)
{
/* If L and R/A/Select or one of the single payload buttons are pressed,
chainload an external payload */
if(devMode || (pressed & SINGLE_PAYLOAD_BUTTONS) || ((pressed & BUTTON_L1) && (pressed & L_PAYLOAD_BUTTONS)))
loadPayload(pressed);
//If screens are inited or the corresponding option is set, load splash screen
if(PDN_GPU_CNT != 1 || CONFIG(8)) loadSplash();
//If R is pressed, boot the non-updated NAND with the FIRM of the opposite one
if(pressed & BUTTON_R1)
{
nandType = updatedSys;
firmSource = !nandType;
}
/* Else, boot the NAND the user set to autoboot or the opposite one, depending on L,
with their own FIRM */
else
{
nandType = CONFIG(0) != !(pressed & BUTTON_L1);
firmSource = nandType;
}
/* If we're booting emuNAND the second emuNAND is set as default and B isn't pressed,
or vice-versa, boot the second emuNAND */
if(nandType && (CONFIG(3) == !(pressed & BUTTON_B))) nandType++;
}
}
//If we need to boot emuNAND, make sure it exists
if(nandType)
{
getEmunandSect(&emuOffset, &emuHeader, &nandType);
if(!nandType) firmSource = 0;
}
//Same if we're using emuNAND as the FIRM source
else if(firmSource)
getEmunandSect(&emuOffset, &emuHeader, &firmSource);
if(!bootType)
{
newConfig |= nandType | (firmSource << 2);
/* If the boot configuration is different from previously, overwrite it.
Just the no-forcing flag being set is not enough */
if((newConfig & 0x2F) != (config & 0x3F))
{
//Preserve user settings (last 26 bits)
newConfig |= config & 0xFFFFFFC0;
fileWrite(&newConfig, configPath, 4);
}
}
loadFirm(firmType, !firmType && updatedSys == !firmSource);
patchExceptionHandlersInstall((u8 *)firm + section[2].offset);
switch(firmType)
{
case 0:
patchNativeFirm(nandType, emuHeader, a9lhMode);
break;
case 3:
patchSafeFirm();
break;
default:
patchLegacyFirm(firmType);
break;
}
launchFirm(bootType);
}
static inline void loadFirm(u32 firmType, u32 externalFirm)
{
section = firm->section;
u32 externalFirmLoaded = externalFirm &&
fileRead(firm, "/luma/firmware.bin") &&
(((u32)section[2].address >> 8) & 0xFF) == (console ? 0x60 : 0x68);
/* If the conditions to load the external FIRM aren't met, or reading fails, or the FIRM
doesn't match the console, load FIRM from CTRNAND */
if(!externalFirmLoaded)
{
const char *firmFolders[4][2] = {{ "00000002", "20000002" },
{ "00000102", "20000102" },
{ "00000202", "20000202" },
{ "00000003", "20000003" }};
firmRead(firm, firmFolders[firmType][console]);
decryptExeFs((u8 *)firm);
}
}
static inline void patchNativeFirm(u32 nandType, u32 emuHeader, u32 a9lhMode)
{
u8 *arm9Section = (u8 *)firm + section[2].offset;
u32 nativeFirmType;
if(console)
{
//Determine if we're booting the 9.0 FIRM
nativeFirmType = arm9Section[0x51] != 0xFF;
//Decrypt ARM9Bin and patch ARM9 entrypoint to skip arm9loader
arm9Loader(arm9Section, nativeFirmType);
firm->arm9Entry = (u8 *)0x801B01C;
}
else
{
//Determine if we're booting the 9.0 FIRM
u8 firm90Hash[0x10] = {0x27, 0x2D, 0xFE, 0xEB, 0xAF, 0x3F, 0x6B, 0x3B, 0xF5, 0xDE, 0x4C, 0x41, 0xDE, 0x95, 0x27, 0x6A};
nativeFirmType = memcmp(section[2].hash, firm90Hash, 0x10) != 0;
}
if(nativeFirmType || nandType || a9lhMode == 2)
{
//Find the Process9 NCCH location
u8 *proc9Offset = getProc9(arm9Section, section[2].size);
//Apply emuNAND patches
if(nandType) patchEmuNAND(arm9Section, proc9Offset, emuHeader);
//Apply FIRM reboot patches, not on 9.0 FIRM as it breaks firmlaunchhax
if(nativeFirmType || a9lhMode == 2) patchReboots(arm9Section, proc9Offset);
}
//Apply FIRM0/1 writes patches on sysNAND to protect A9LH
if(a9lhMode && !nandType) patchFirmWrites(arm9Section, 1);
//Apply signature checks patches
u32 sigOffset,
sigOffset2;
getSigChecks(arm9Section, section[2].size, &sigOffset, &sigOffset2);
*(u16 *)sigOffset = sigPatch[0];
*(u16 *)sigOffset2 = sigPatch[0];
*((u16 *)sigOffset2 + 1) = sigPatch[1];
if(CONFIG(5))
{
//Apply UNITINFO patch
u8 *unitInfoOffset = getUnitInfoValueSet(arm9Section, section[2].size);
*unitInfoOffset = unitInfoPatch;
}
//Replace the FIRM loader with the injector
injectLoader();
}
static inline void patchEmuNAND(u8 *arm9Section, u8 *proc9Offset, u32 emuHeader)
{
//Copy emuNAND code
void *emuCodeOffset = getEmuCode(proc9Offset);
memcpy(emuCodeOffset, emunand, emunand_size);
//Add the data of the found emuNAND
u32 *pos_offset = (u32 *)memsearch(emuCodeOffset, "NAND", emunand_size, 4);
u32 *pos_header = (u32 *)memsearch(emuCodeOffset, "NCSD", emunand_size, 4);
*pos_offset = emuOffset;
*pos_header = emuHeader;
//Find and add the SDMMC struct
u32 *pos_sdmmc = (u32 *)memsearch(emuCodeOffset, "SDMC", emunand_size, 4);
*pos_sdmmc = getSDMMC(arm9Section, section[2].size);
//Calculate offset for the hooks
u32 branchOffset = (u32)emuCodeOffset - (u32)firm -
section[2].offset + (u32)section[2].address;
//Add emuNAND hooks
u32 emuRead,
emuWrite;
getEmuRW(arm9Section, section[2].size, &emuRead, &emuWrite);
*(u16 *)emuRead = nandRedir[0];
*((u16 *)emuRead + 1) = nandRedir[1];
*((u32 *)emuRead + 1) = branchOffset;
*(u16 *)emuWrite = nandRedir[0];
*((u16 *)emuWrite + 1) = nandRedir[1];
*((u32 *)emuWrite + 1) = branchOffset;
//Set MPU for emu code region
u32 *mpuOffset = getMPU(arm9Section, section[2].size);
*mpuOffset = mpuPatch[0];
*(mpuOffset + 6) = mpuPatch[1];
*(mpuOffset + 9) = mpuPatch[2];
}
static inline void patchReboots(u8 *arm9Section, u8 *proc9Offset)
{
//Calculate offset for the firmlaunch code
void *rebootOffset = getReboot(arm9Section, section[2].size);
//Calculate offset for the fOpen function
u32 fOpenOffset = getfOpen(proc9Offset, rebootOffset);
//Copy firmlaunch code
memcpy(rebootOffset, reboot, reboot_size);
//Put the fOpen offset in the right location
u32 *pos_fopen = (u32 *)memsearch(rebootOffset, "OPEN", reboot_size, 4);
*pos_fopen = fOpenOffset;
}
static inline void injectLoader(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;
}
}
static inline void patchLegacyFirm(u32 firmType)
{
//On N3DS, decrypt ARM9Bin and patch ARM9 entrypoint to skip arm9loader
if(console)
{
arm9Loader((u8 *)firm + section[3].offset, 0);
firm->arm9Entry = (u8 *)0x801301C;
}
const patchData twlPatches[] = {
{{0x1650C0, 0x165D64}, {{ 6, 0x00, 0x20, 0x4E, 0xB0, 0x70, 0xBD }}, 0},
{{0x173A0E, 0x17474A}, { .type1 = 0x2001 }, 1},
{{0x174802, 0x17553E}, { .type1 = 0x2000 }, 2},
{{0x174964, 0x1756A0}, { .type1 = 0x2000 }, 2},
{{0x174D52, 0x175A8E}, { .type1 = 0x2001 }, 2},
{{0x174D5E, 0x175A9A}, { .type1 = 0x2001 }, 2},
{{0x174D6A, 0x175AA6}, { .type1 = 0x2001 }, 2},
{{0x174E56, 0x175B92}, { .type1 = 0x2001 }, 1},
{{0x174E58, 0x175B94}, { .type1 = 0x4770 }, 1}
},
agbPatches[] = {
{{0x9D2A8, 0x9DF64}, {{ 6, 0x00, 0x20, 0x4E, 0xB0, 0x70, 0xBD }}, 0},
{{0xD7A12, 0xD8B8A}, { .type1 = 0xEF26 }, 1}
};
/* Calculate the amount of patches to apply. Only count the boot screen patch for AGB_FIRM
if the matching option was enabled (keep it as last) */
u32 numPatches = firmType == 1 ? (sizeof(twlPatches) / sizeof(patchData)) :
(sizeof(agbPatches) / sizeof(patchData) - !CONFIG(7));
const patchData *patches = firmType == 1 ? twlPatches : agbPatches;
//Patch
for(u32 i = 0; i < numPatches; i++)
{
switch(patches[i].type)
{
case 0:
memcpy((u8 *)firm + patches[i].offset[console], patches[i].patch.type0 + 1, patches[i].patch.type0[0]);
break;
case 2:
*(u16 *)((u8 *)firm + patches[i].offset[console] + 2) = 0;
case 1:
*(u16 *)((u8 *)firm + patches[i].offset[console]) = patches[i].patch.type1;
break;
}
}
}
static inline void patchSafeFirm(void)
{
u8 *arm9Section = (u8 *)firm + section[2].offset;
if(console)
{
//Decrypt ARM9Bin and patch ARM9 entrypoint to skip arm9loader
arm9Loader(arm9Section, 0);
firm->arm9Entry = (u8 *)0x801B01C;
}
//Apply FIRM0/1 writes patches to protect A9LH
patchFirmWrites(arm9Section, console);
}
static void patchFirmWrites(u8 *arm9Section, u32 mode)
{
if(mode)
{
u16 *writeOffset = getFirmWrite(arm9Section, section[2].size);
*writeOffset = writeBlock[0];
*(writeOffset + 1) = writeBlock[1];
}
else
{
u16 *writeOffset = getFirmWriteSafe(arm9Section, section[2].size);
*writeOffset = writeBlockSafe[0];
*(writeOffset + 1) = writeBlockSafe[1];
}
}
static inline void launchFirm(u32 bootType)
{
//Copy FIRM sections to respective memory locations
for(u32 i = 0; i < 4 && section[i].size; i++)
memcpy(section[i].address, (u8 *)firm + section[i].offset, section[i].size);
//Determine the ARM11 entry to use
vu32 *arm11;
if(bootType) arm11 = (u32 *)0x1FFFFFFC;
else
{
deinitScreens();
arm11 = (u32 *)0x1FFFFFF8;
}
//Set ARM11 kernel entrypoint
*arm11 = (u32)firm->arm11Entry;
//Final jump to ARM9 kernel
((void (*)())firm->arm9Entry)();
}