void ctr_twl_keyslot_setup(void)
{
//Only a9lh really needs to bother with this, and it really only needs to happen once, before ITCM gets messed up.
static bool setup = false;
if (!setup && ctr_detect_a9lh_entry())
{
uint32_t* TwlCustId = (uint32_t*) (0x01FFB808);
uint32_t TwlKeyX[4];
alignas(32) uint8_t TwlKeyY[16];
// thanks b1l1s & Normmatt
// see source from https://gbatemp.net/threads/release-twltool-dsi-downgrading-save-injection-etc-multitool.393488/
const char* nintendo = "NINTENDO";
TwlKeyX[0] = (TwlCustId[0] ^ 0xB358A6AF) | 0x80000000;
TwlKeyX[3] = TwlCustId[1] ^ 0x08C267B7;
memcpy(TwlKeyX + 1, nintendo, 8);
// see: https://www.3dbrew.org/wiki/Memory_layout#ARM9_ITCM
uint32_t TwlKeyYW3 = 0xE1A00005;
memcpy(TwlKeyY, (uint8_t*) 0x01FFD3C8, 12);
memcpy(TwlKeyY + 12, &TwlKeyYW3, 4);
setup_aeskeyX(0x03, (uint8_t*)TwlKeyX);
setup_aeskeyY(0x03, TwlKeyY);
use_aeskey(0x03);
}
setup = true;
}
static inline void check_and_do_twl_init()
{
static bool setup = false;
if (!setup && ctr_detect_a9lh_entry())
{
ctr_twl_keyslot_setup();
}
}
static inline void check_and_do_n3ds_init()
{
static bool setup = false;
if (!setup && ctr_detect_a9lh_entry() && ctr_get_system_type() == SYSTEM_N3DS)
{
ctr_n3ds_ctrnand_keyslot_setup();
}
}