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kloader.c
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/*
* Copyright 2014, winocm. <winocm@icloud.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $Id$
*/
/*
* kloader: armv7(s) devices = 3.1 - 10.3.3
* tested on: iOS 4.0 | 9.3.5 | 8.4.1 | 10.3.3
* kloader64: iPhone 5S, iPad mini 2+3+4 - HomePod - iPhone6+Plus, iPod6 - iPadAir+2 = 7.0 - 10.3.3+
*/
#include <stdio.h>
#include <signal.h>
#include <stdint.h>
#include <sys/stat.h>
#include <mach/mach.h>
#include <sys/sysctl.h>
#include <CoreFoundation/CoreFoundation.h>
typedef mach_port_t io_service_t;
extern mach_port_t kIOMasterPortDefault;
extern kern_return_t IOPMSleepSystem(mach_port_t);
extern mach_port_t IOPMFindPowerManagement(mach_port_t);
/*
* ARM page bits for L1 sections.
*/
#define L1_SHIFT 20 /* log2(1MB) */
#define L1_SECT_PROTO (1 << 1) /* 0b10 */
#define L1_SECT_B_BIT (1 << 2)
#define L1_SECT_C_BIT (1 << 3)
#define L1_SECT_SORDER (0) /* 0b00, not cacheable, strongly ordered. */
#define L1_SECT_SH_DEVICE (L1_SECT_B_BIT)
#define L1_SECT_WT_NWA (L1_SECT_C_BIT)
#define L1_SECT_WB_NWA (L1_SECT_B_BIT | L1_SECT_C_BIT)
#define L1_SECT_S_BIT (1 << 16)
#define L1_SECT_AP_URW (1 << 10) | (1 << 11)
#define L1_SECT_PFN(x) (x & 0xFFF00000)
#define L1_SECT_DEFPROT (L1_SECT_AP_URW)
#define L1_SECT_DEFCACHE (L1_SECT_SORDER)
#define L1_PROTO_TTE(paddr) (L1_SECT_PFN(paddr) | L1_SECT_S_BIT | L1_SECT_DEFPROT | L1_SECT_DEFCACHE | L1_SECT_PROTO)
#define PFN_SHIFT 2
#define TTB_OFFSET(vaddr) ((vaddr >> L1_SHIFT) << PFN_SHIFT)
/*
* RAM physical base begin.
*/
#define S5L8930_PHYS_OFF 0x40000000
#define S5L8940_PHYS_OFF 0x80000000
#define S5l8960_PHYS_OFF 0x800800000
#define T7000_PHYS_OFF 0x800e00000
// https://github.com/saelo/ios-kern-utils/tree/master/lib/kernel
#define ptrsize sizeof(uintptr_t)
#define KERNEL_DUMP_SIZE 0xd00000 // 0xF00000 | 0xc00000
#ifdef __arm64__
#define IMAGE_OFFSET 0x2000
#define KASLR_SLIDE 0x21000000
#define MACHO_HEADER_MAGIC 0xfeedfacf
#define KERNEL_SEARCH_ADDRESS 0xffffff8000000000
#define KERNEL_SEARCH_ADDRESS_9 0xffffff8004004000
#define KERNEL_SEARCH_ADDRESS_10 0xfffffff007004000
#else
#define IMAGE_OFFSET 0x1000
#define MACHO_HEADER_MAGIC 0xfeedface
#define KERNEL_SEARCH_ADDRESS 0x81200000
#define KERNEL_SEARCH_ADDRESS_2 0xC0000000
#endif
/*
* Shadowmap begin and end. 15MB of shadowmap is enough for the kernel.
* We don't need to invalidate unified D/I TLB or any cache lines
* since the kernel is mapped as writethrough memory, and these
* addresses are guaranteed to not be translated.
* (Accesses will cause segmentation faults due to failure on L1 translation.)
*
* Clear the shadowmappings when done owning the kernel.
*
* 0x7ff0'0000 is also below the limit for vm_read and such, so that's also *great*.
* (2048 bytes)
*/
#define SHADOWMAP_BEGIN 0x7f000000
#define SHADOWMAP_END 0x7ff00000
#define SHADOWMAP_GRANULARITY 0x00100000
#define SHADOWMAP_SIZE_BYTES (SHADOWMAP_END - SHADOWMAP_BEGIN)
#define SHADOWMAP_BEGIN_OFF TTB_OFFSET(SHADOWMAP_BEGIN)
#define SHADOWMAP_END_OFF TTB_OFFSET(SHADOWMAP_END)
#define SHADOWMAP_SIZE (SHADOWMAP_END_OFF - SHADOWMAP_BEGIN_OFF)
#define SHADOWMAP_BEGIN_IDX (SHADOWMAP_BEGIN_OFF >> PFN_SHIFT)
#define SHADOWMAP_END_IDX (SHADOWMAP_END_OFF >> PFN_SHIFT)
#define TTB_SIZE 4096
static mach_port_t kernel_task = 0;
static uint32_t ttb_template[TTB_SIZE] = { };
static void *ttb_template_ptr = &ttb_template[0];
static vm_address_t kernel_base = S5L8940_PHYS_OFF;
typedef struct pmap_partial_t
{
uint32_t tte_virt;
uint32_t tte_phys;
/*
* ...
*/
} pmap_partial_t;
/* --- planetbeing patchfinder --- */
static uint32_t bit_range(uint32_t x, int start, int end)
{
x = (x << (31 - start)) >> (31 - start);
x = (x >> end);
return x;
}
static uint32_t ror(uint32_t x, int places)
{
return (x >> places) | (x << (32 - places));
}
static int thumb_expand_imm_c(uint16_t imm12)
{
if (bit_range(imm12, 11, 10) == 0) {
switch (bit_range(imm12, 9, 8)) {
case 0:
return bit_range(imm12, 7, 0);
case 1:
return (bit_range(imm12, 7, 0) << 16) | bit_range(imm12, 7, 0);
case 2:
return (bit_range(imm12, 7, 0) << 24) | (bit_range(imm12, 7, 0) << 8);
case 3:
return (bit_range(imm12, 7, 0) << 24) | (bit_range(imm12, 7, 0) << 16) | (bit_range(imm12, 7, 0) << 8) | bit_range(imm12, 7, 0);
default:
return 0;
}
} else {
uint32_t unrotated_value = 0x80 | bit_range(imm12, 6, 0);
return ror(unrotated_value, bit_range(imm12, 11, 7));
}
}
static int insn_is_32bit(uint16_t *i)
{
return (*i & 0xe000) == 0xe000 && (*i & 0x1800) != 0x0;
}
static int insn_is_bl(uint16_t *i)
{
if ((*i & 0xf800) == 0xf000 && (*(i + 1) & 0xd000) == 0xd000)
return 1;
else if ((*i & 0xf800) == 0xf000 && (*(i + 1) & 0xd001) == 0xc000)
return 1;
else
return 0;
}
static uint32_t insn_bl_imm32(uint16_t *i)
{
uint16_t insn0 = *i;
uint16_t insn1 = *(i + 1);
uint32_t s = (insn0 >> 10) & 1;
uint32_t j1 = (insn1 >> 13) & 1;
uint32_t j2 = (insn1 >> 11) & 1;
uint32_t i1 = ~(j1 ^ s) & 1;
uint32_t i2 = ~(j2 ^ s) & 1;
uint32_t imm10 = insn0 & 0x3ff;
uint32_t imm11 = insn1 & 0x7ff;
uint32_t imm32 = (imm11 << 1) | (imm10 << 12) | (i2 << 22) | (i1 << 23) | (s ? 0xff000000 : 0);
return imm32;
}
static int insn_is_b_conditional(uint16_t *i)
{
return (*i & 0xF000) == 0xD000 && (*i & 0x0F00) != 0x0F00 && (*i & 0x0F00) != 0xE;
}
static int insn_is_b_unconditional(uint16_t *i)
{
if ((*i & 0xF800) == 0xE000)
return 1;
else if ((*i & 0xF800) == 0xF000 && (*(i + 1) & 0xD000) == 9)
return 1;
else
return 0;
}
static int insn_is_ldr_literal(uint16_t *i)
{
return (*i & 0xF800) == 0x4800 || (*i & 0xFF7F) == 0xF85F;
}
static int insn_ldr_literal_rt(uint16_t *i)
{
if ((*i & 0xF800) == 0x4800)
return (*i >> 8) & 7;
else if ((*i & 0xFF7F) == 0xF85F)
return (*(i + 1) >> 12) & 0xF;
else
return 0;
}
static int insn_ldr_literal_imm(uint16_t *i)
{
if ((*i & 0xF800) == 0x4800)
return (*i & 0xF) << 2;
else if ((*i & 0xFF7F) == 0xF85F)
return (*(i + 1) & 0xFFF) *(((*i & 0x0800) == 0x0800) ? 1 : -1);
else
return 0;
}
static int insn_ldr_imm_rt(uint16_t *i)
{
return (*i & 7);
}
static int insn_ldr_imm_rn(uint16_t *i)
{
return ((*i >> 3) & 7);
}
static int insn_ldr_imm_imm(uint16_t *i)
{
return ((*i >> 6) & 0x1F);
}
static int insn_is_add_reg(uint16_t *i)
{
if ((*i & 0xFE00) == 0x1800)
return 1;
else if ((*i & 0xFF00) == 0x4400)
return 1;
else if ((*i & 0xFFE0) == 0xEB00)
return 1;
else
return 0;
}
static int insn_add_reg_rd(uint16_t *i)
{
if ((*i & 0xFE00) == 0x1800)
return (*i & 7);
else if ((*i & 0xFF00) == 0x4400)
return (*i & 7) | ((*i & 0x80) >> 4);
else if ((*i & 0xFFE0) == 0xEB00)
return (*(i + 1) >> 8) & 0xF;
else
return 0;
}
static int insn_add_reg_rn(uint16_t *i)
{
if ((*i & 0xFE00) == 0x1800)
return ((*i >> 3) & 7);
else if ((*i & 0xFF00) == 0x4400)
return (*i & 7) | ((*i & 0x80) >> 4);
else if ((*i & 0xFFE0) == 0xEB00)
return (*i & 0xF);
else
return 0;
}
static int insn_add_reg_rm(uint16_t *i)
{
if ((*i & 0xFE00) == 0x1800)
return (*i >> 6) & 7;
else if ((*i & 0xFF00) == 0x4400)
return (*i >> 3) & 0xF;
else if ((*i & 0xFFE0) == 0xEB00)
return *(i + 1) & 0xF;
else
return 0;
}
static int insn_is_movt(uint16_t *i)
{
return (*i & 0xFBF0) == 0xF2C0 && (*(i + 1) & 0x8000) == 0;
}
static int insn_movt_rd(uint16_t *i)
{
return (*(i + 1) >> 8) & 0xF;
}
static int insn_movt_imm(uint16_t *i)
{
return ((*i & 0xF) << 12) | ((*i & 0x0400) << 1) | ((*(i + 1) & 0x7000) >> 4) | (*(i + 1) & 0xFF);
}
static int insn_is_mov_imm(uint16_t *i)
{
if ((*i & 0xF800) == 0x2000)
return 1;
else if ((*i & 0xFBEF) == 0xF04F && (*(i + 1) & 0x8000) == 0)
return 1;
else if ((*i & 0xFBF0) == 0xF240 && (*(i + 1) & 0x8000) == 0)
return 1;
else
return 0;
}
static int insn_mov_imm_rd(uint16_t *i)
{
if ((*i & 0xF800) == 0x2000)
return (*i >> 8) & 7;
else if ((*i & 0xFBEF) == 0xF04F && (*(i + 1) & 0x8000) == 0)
return (*(i + 1) >> 8) & 0xF;
else if ((*i & 0xFBF0) == 0xF240 && (*(i + 1) & 0x8000) == 0)
return (*(i + 1) >> 8) & 0xF;
else
return 0;
}
static int insn_mov_imm_imm(uint16_t *i)
{
if ((*i & 0xF800) == 0x2000)
return *i & 0xF;
else if ((*i & 0xFBEF) == 0xF04F && (*(i + 1) & 0x8000) == 0)
return thumb_expand_imm_c(((*i & 0x0400) << 1) | ((*(i + 1) & 0x7000) >> 4) | (*(i + 1) & 0xFF));
else if ((*i & 0xFBF0) == 0xF240 && (*(i + 1) & 0x8000) == 0)
return ((*i & 0xF) << 12) | ((*i & 0x0400) << 1) | ((*(i + 1) & 0x7000) >> 4) | (*(i + 1) & 0xFF);
else
return 0;
}
static void *buggy_memmem(const void *haystack, size_t haystacklen, const void *needle, size_t needlelen)
{
if (haystack == NULL || haystacklen == 0x0 || needle == NULL || needlelen == 0x0) {
printf("[ERROR]: Invalid argument(s) for buggy_memmem.\n");
exit(1);
}
for (size_t i = 0; i < haystacklen; i++) {
if (*(uint8_t *)(haystack + i) == *(uint8_t *)needle && i + needlelen <= haystacklen && 0x0 == memcmp(((uint8_t *)haystack) + i, needle, needlelen)) {
return (void *)(((uint8_t *)haystack) + i);
}
}
return NULL;
}
// Given an instruction, search backwards until an instruction is found matching the specified criterion.
static uint16_t *find_last_insn_matching(uint32_t region, uint8_t *kdata, size_t ksize, uint16_t *current_instruction, int (*match_func) (uint16_t *))
{
while ((uintptr_t)current_instruction > (uintptr_t)kdata) {
if (insn_is_32bit(current_instruction - 2) && !insn_is_32bit(current_instruction - 3)) {
current_instruction -= 2;
} else {
--current_instruction;
}
if (match_func(current_instruction)) {
return current_instruction;
}
}
return NULL;
}
// Given an instruction and a register, find the PC-relative address that was stored inside the register by the time the instruction was reached.
static uint32_t find_pc_rel_value(uint32_t region, uint8_t *kdata, size_t ksize, uint16_t *insn, int reg)
{
// Find the last instruction that completely wiped out this register
int found = 0;
uint16_t *current_instruction = insn;
while ((uintptr_t)current_instruction > (uintptr_t)kdata) {
if (insn_is_32bit(current_instruction - 2)) {
current_instruction -= 2;
} else {
--current_instruction;
}
if (insn_is_mov_imm(current_instruction) && insn_mov_imm_rd(current_instruction) == reg) {
found = 1;
break;
}
if (insn_is_ldr_literal(current_instruction) && insn_ldr_literal_rt(current_instruction) == reg) {
found = 1;
break;
}
}
if (!found)
return 0;
// Step through instructions, executing them as a virtual machine, only caring about instructions that affect the target register and are commonly used for PC-relative addressing.
uint32_t value = 0;
while ((uintptr_t)current_instruction < (uintptr_t)insn) {
if (insn_is_mov_imm(current_instruction) && insn_mov_imm_rd(current_instruction) == reg) {
value = insn_mov_imm_imm(current_instruction);
} else if (insn_is_ldr_literal(current_instruction) && insn_ldr_literal_rt(current_instruction) == reg) {
value = *(uint32_t *)(kdata + (((((uintptr_t)current_instruction - (uintptr_t)kdata) + 4) & 0xFFFFFFFC) + insn_ldr_literal_imm(current_instruction)));
} else if (insn_is_movt(current_instruction) && insn_movt_rd(current_instruction) == reg) {
value |= insn_movt_imm(current_instruction) << 16;
} else if (insn_is_add_reg(current_instruction) && insn_add_reg_rd(current_instruction) == reg) {
if (insn_add_reg_rm(current_instruction) != 15 || insn_add_reg_rn(current_instruction) != reg) {
// Can't handle this kind of operation!
return 0;
}
value += ((uintptr_t)current_instruction - (uintptr_t)kdata) + 4;
}
current_instruction += insn_is_32bit(current_instruction) ? 2 : 1;
}
return value;
}
// Find PC-relative references to a certain address (relative to kdata). This is basically a virtual machine that only cares about instructions used in PC-relative addressing, so no branches, etc.
static uint16_t *find_literal_ref(uint32_t region, uint8_t *kdata, size_t ksize, uint16_t *insn, uint32_t address)
{
uint32_t value[16];
uint16_t *current_instruction = insn;
memset(value, 0x0, sizeof(value));
while ((uintptr_t)current_instruction < (uintptr_t)(kdata + ksize)) {
if (insn_is_mov_imm(current_instruction)) {
value[insn_mov_imm_rd(current_instruction)] = insn_mov_imm_imm(current_instruction);
} else if (insn_is_ldr_literal(current_instruction)) {
uintptr_t literal_address = (uintptr_t)kdata + ((((uintptr_t)current_instruction - (uintptr_t)kdata) + 4) & 0xFFFFFFFC) + insn_ldr_literal_imm(current_instruction);
if (literal_address >= (uintptr_t) kdata && (literal_address + 4) <= ((uintptr_t)kdata + ksize)) {
value[insn_ldr_literal_rt(current_instruction)] = *(uint32_t *)(literal_address);
}
} else if (insn_is_movt(current_instruction)) {
value[insn_movt_rd(current_instruction)] |= insn_movt_imm(current_instruction) << 16;
} else if (insn_is_add_reg(current_instruction)) {
int reg = insn_add_reg_rd(current_instruction);
if (insn_add_reg_rm(current_instruction) == 15 && insn_add_reg_rn(current_instruction) == reg) {
value[reg] += ((uintptr_t)current_instruction - (uintptr_t)kdata) + 4;
if (value[reg] == address) {
return current_instruction;
}
}
}
current_instruction += insn_is_32bit(current_instruction) ? 2 : 1;
}
return NULL;
}
// This points to kernel_pmap. Use that to change the page tables if necessary.
uint32_t find_pmap_location(uint32_t region, uint8_t *kdata, size_t ksize)
{
// Find location of the pmap_map_bd string.
uint8_t *pmap_map_bd = memmem(kdata, ksize, "\"pmap_map_bd\"", sizeof("\"pmap_map_bd\""));
if (!pmap_map_bd)
return 0;
// Find a reference to the pmap_map_bd string. That function also references kernel_pmap
uint16_t *ptr = find_literal_ref(region, kdata, ksize, (uint16_t *)kdata, (uintptr_t)pmap_map_bd - (uintptr_t)kdata);
if (!ptr)
return 0;
// Find the beginning of it (we may have a version that throws panic after the function end).
while (*ptr != 0xB5F0) {
if ((uint8_t *)ptr == kdata)
return 0;
ptr--;
}
// Find the end of it.
const uint8_t search_function_end[] = { 0xF0, 0xBD };
ptr = memmem(ptr, ksize - ((uintptr_t)ptr - (uintptr_t)kdata), search_function_end, sizeof(search_function_end));
if (!ptr)
return 0;
// Find the last BL before the end of it. The third argument to it should be kernel_pmap
uint16_t *bl = find_last_insn_matching(region, kdata, ksize, ptr, insn_is_bl);
if (!bl)
return 0;
// Find the last LDR R2, [R*] before it that's before any branches. If there are branches, then we have a version of the function that assumes kernel_pmap instead of being passed it.
uint16_t *ldr_r2 = NULL;
uint16_t *current_instruction = bl;
while ((uintptr_t)current_instruction > (uintptr_t)kdata) {
if (insn_is_32bit(current_instruction - 2) && !insn_is_32bit(current_instruction - 3)) {
current_instruction -= 2;
} else {
--current_instruction;
}
if (insn_ldr_imm_rt(current_instruction) == 2 && insn_ldr_imm_imm(current_instruction) == 0) {
ldr_r2 = current_instruction;
break;
} else if (insn_is_b_conditional(current_instruction) || insn_is_b_unconditional(current_instruction)) {
break;
}
}
// The function has a third argument, which must be kernel_pmap. Find out its address
if (ldr_r2)
return find_pc_rel_value(region, kdata, ksize, ldr_r2, insn_ldr_imm_rn(ldr_r2));
// The function has no third argument, Follow the BL.
uint32_t imm32 = insn_bl_imm32(bl);
uint32_t target = ((uintptr_t)bl - (uintptr_t)kdata) + 4 + imm32;
if (target > ksize)
return 0;
// Find the first PC-relative reference in this function.
int found = 0;
int rd;
current_instruction = (uint16_t *)(kdata + target);
while ((uintptr_t)current_instruction < (uintptr_t)(kdata + ksize)) {
if (insn_is_add_reg(current_instruction) && insn_add_reg_rm(current_instruction) == 15) {
found = 1;
rd = insn_add_reg_rd(current_instruction);
current_instruction += insn_is_32bit(current_instruction) ? 2 : 1;
break;
}
current_instruction += insn_is_32bit(current_instruction) ? 2 : 1;
}
if (!found)
return 0;
return find_pc_rel_value(region, kdata, ksize, current_instruction, rd);
}
// Function to find the syscall 0 function pointer. Used to modify the syscall table to call our own code.
uint32_t find_syscall0(uint32_t region, uint8_t *kdata, size_t ksize)
{
const uint8_t syscall1_search[] = { 0x90, 0xB5, 0x01, 0xAF, 0x82, 0xB0, 0x09, 0x68, 0x01, 0x24, 0x00, 0x23 };
void *ptr = memmem(kdata, ksize, syscall1_search, sizeof(syscall1_search));
if (!ptr)
return 0;
// Search for a pointer to syscall 1
uint32_t ptr_address = (uintptr_t)ptr - (uintptr_t)kdata + region;
uint32_t function = ptr_address | 1;
void *syscall1_entry = memmem(kdata, ksize, &function, sizeof(function));
if (!syscall1_entry)
return 0;
// Calculate the address of syscall 0 from the address of the syscall 1 entry
return (uintptr_t)syscall1_entry - (uintptr_t)kdata - 0x18;
}
uint32_t find_larm_init_tramp(uint32_t region, uint8_t *kdata, size_t ksize)
{
#ifdef __arm64__
const uint8_t search[] = { 0x01, 0x00, 0x00, 0x14, 0xDF, 0x4F, 0x03, 0xD5 };
void *ptr = buggy_memmem(kdata, ksize, search, sizeof(search));
if (ptr)
return ((uintptr_t)ptr) - 0x8 - ((uintptr_t)kdata);
#else
const uint8_t search[] = { 0x0E, 0xE0, 0x9F, 0xE7, 0xFF, 0xFF, 0xFF, 0xEA, 0xC0, 0x00, 0x0C, 0xF1 };
void *ptr = buggy_memmem(kdata, ksize, search, sizeof(search));
if (ptr)
return ((uintptr_t)ptr) - ((uintptr_t)kdata);
const uint8_t search2[] = { 0x9F, 0xE5, 0xFF, 0xFF, 0xFF, 0xEA, 0xC0, 0x00, 0x0C, 0xF1 };
ptr = buggy_memmem(kdata, ksize, search2, sizeof(search2));
if (ptr)
return ((uintptr_t)ptr) - 0x2 - ((uintptr_t)kdata);
#endif
printf("[ERROR]: Failed to locate larm_init_tramp.\n");
exit(1);
}
static task_t get_kernel_task(void)
{
task_t kernel_task = MACH_PORT_NULL;
printf("[INFO]: Attempting to get kernel_task...\n");
kern_return_t ret = task_for_pid(mach_task_self(), 0x0, &kernel_task);
if (ret != KERN_SUCCESS) {
ret = host_get_special_port(mach_host_self(), HOST_LOCAL_NODE, 0x4, &kernel_task);
if (ret != KERN_SUCCESS) {
printf("[ERROR]: Failed to get both task_for_pid & host_get_special_port.\n");
exit(-1);
}
}
printf("OK: kernel_task = 0x%08x\n", kernel_task); return kernel_task;
}
static vm_address_t get_kernel_base(task_t kernel_task, uint64_t kernel_vers) {
vm_size_t size;
uint64_t addr = 0x0;
unsigned int depth = 0;
vm_region_submap_info_data_64_t info;
mach_msg_type_number_t info_count = VM_REGION_SUBMAP_INFO_COUNT_64;
printf("[INFO]: Attempting to get kernel_base...\n");
#ifdef __arm__
if (kernel_vers <= 10) {
addr = KERNEL_SEARCH_ADDRESS_2;
return addr;
} else {
addr = KERNEL_SEARCH_ADDRESS;
}
#elif __arm64__
addr = KERNEL_SEARCH_ADDRESS;
#endif
while (1) {
if (vm_region_recurse_64(kernel_task, (vm_address_t *)&addr, &size, &depth, (vm_region_info_t)&info, &info_count) != KERN_SUCCESS)
break;
if ((size > 1024 * 1024 * 1024)) {
pointer_t buf;
addr += 0x200000;
mach_msg_type_number_t sz = 0x0;
vm_read(kernel_task, addr + IMAGE_OFFSET, 0x512, &buf, &sz);
if (*((uint32_t *)buf) != MACHO_HEADER_MAGIC) {
addr -= 0x200000;
vm_read(kernel_task, addr + IMAGE_OFFSET, 0x512, &buf, &sz);
if (*((uint32_t *)buf) != MACHO_HEADER_MAGIC)
break;
}
printf("OK: kernel_base = 0x%08lx\n", (uintptr_t)addr);
return addr;
}
addr += size;
}
printf("[ERROR]: Failed to get kernel_base.\n");
exit(1);
}
#ifdef __arm64__
// https://github.com/JonathanSeals/kernelversionhacker
// https://github.com/kpwn/iOSRE/blob/master/wiki/Kernel-Patch-Protection-(KPP).md
static vm_address_t get_kernel_base_plus(task_t kernel_task, uint64_t kernel_vers)
{
uint64_t addr = 0x0;
printf("[INFO]: Attempting to get kernel_base...\n");
if (kernel_vers == 15) {
addr = KERNEL_SEARCH_ADDRESS_9 + KASLR_SLIDE;
} else if (kernel_vers == 16 || kernel_vers == 17) {
addr = KERNEL_SEARCH_ADDRESS_10 + KASLR_SLIDE;
} else if (kernel_vers >= 18 || kernel_vers <= 18.5) {
addr = KERNEL_SEARCH_ADDRESS_10 + KASLR_SLIDE;
} else if (kernel_vers >= 18.5) {
// [NOTE]: kernel_base isn't always 0x4000 at the end since iOS 12.2,
// see: https://twitter.com/jaakerblom/status/1110835960143466496
printf("[WARNING]: iOS 12.2 or above detected.\n");
printf(" Using default address anyways. You are on your own.\n");
addr = KERNEL_SEARCH_ADDRESS_10 + KASLR_SLIDE;
} else {
return -0x1;
}
while (1) {
char *buf;
mach_msg_type_number_t sz = 0x0;
kern_return_t ret = vm_read(kernel_task, addr, 0x200, (vm_offset_t *)&buf, &sz);
if (ret) {
goto next;
}
if (*((uint32_t *)buf) == MACHO_HEADER_MAGIC) {
int ret = vm_read(kernel_task, addr, 0x1000, (vm_offset_t *)&buf, &sz);
if (ret != KERN_SUCCESS) {
printf("[ERROR]: Failed vm_read (%i)\n", ret);
goto next;
}
for (uintptr_t i = addr; i < (addr + 0x2000); i += (ptrsize)) {
int ret = vm_read(kernel_task, i, 0x120, (vm_offset_t *)&buf, (mach_msg_type_number_t *)&sz);
if (ret != KERN_SUCCESS) {
printf("[ERROR]: Failed vm_read (%i)\n", ret);
exit(-1);
}
if (!strcmp(buf, "__text") && !strcmp(buf + 0x10, "__PRELINK_TEXT")) {
printf("OK: kernel_base = 0x%08lx\n", (uintptr_t)addr);
return addr;
}
}
}
next:
addr -= 0x200000;
}
printf("[ERROR]: Failed to get kernel_base.\n");
exit(1);
}
#endif
uint32_t PHYS_OFF = S5L8930_PHYS_OFF;
uint32_t phys_addr_remap = 0x5fe00000; // 0x9fe00000
static void generate_ttb_entries(void)
{
uint32_t vaddr, vaddr_end, paddr, i;
paddr = PHYS_OFF;
vaddr = SHADOWMAP_BEGIN;
vaddr_end = SHADOWMAP_END;
for (i = vaddr; i <= vaddr_end; i += SHADOWMAP_GRANULARITY, paddr += SHADOWMAP_GRANULARITY) {
#if SPURIOUS_DEBUG_OUTPUT
printf("[INFO]: protoTTE = 0x%08x, VA = 0x%08x -> PA = 0x%08x\n", L1_PROTO_TTE(paddr), i, paddr);
#endif
ttb_template[TTB_OFFSET(i) >> PFN_SHIFT] = L1_PROTO_TTE(paddr);
}
/*
* Remap TTE for iBoot load address.
*/
uint32_t ttb_remap_addr_base = 0x7fe00000;
ttb_template[TTB_OFFSET(ttb_remap_addr_base) >> PFN_SHIFT] = L1_PROTO_TTE(phys_addr_remap);
#if SPURIOUS_DEBUG_OUTPUT
printf("[INFO]: Remapped 0x%08x to 0x%08x (TTE: 0x%08x)\n", ttb_remap_addr_base, phys_addr_remap, L1_PROTO_TTE(phys_addr_remap));
printf("[INFO]: TTE offset beginning for shadowmap = 0x%08x\n", SHADOWMAP_BEGIN_OFF);
printf("[INFO]: TTE offset ending for shadowmap = 0x%08x\n", SHADOWMAP_END_OFF);
printf("[INFO]: TTE size = 0x%08x\n", SHADOWMAP_SIZE);
#endif
printf("[INFO]: Base address for remap = 0x%08x, physBase = 0x%08x\n", PHYS_OFF, phys_addr_remap);
return;
}
uint32_t larm_init_tramp;
uint32_t kern_base, kern_tramp_phys;
uint32_t flush_dcache, invalidate_icache;
extern char shellcode_begin[], shellcode_end[];
int main(int argc, char *argv[]) {
size_t size;
uint32_t chunksize = 2048;
if (argc != 2) {
printf("usage: %s [img]\n\n", argv[0]);
printf("This will destroy the current running OS instance and fire up the specified image.\n");
printf("You have been warned.\n");
exit(1);
}
if (open(argv[1], O_RDONLY) == -0x1) {
printf("[ERROR]: Failed to open %s.\n", argv[1]);
return -0x1;
}
/*
* Get physbase.
*/
sysctlbyname("kern.version", NULL, &size, NULL, 0x0);
char *kern_vers = malloc(size);
if (sysctlbyname("kern.version", kern_vers, &size, NULL, 0x0) == -0x1) {
printf("[ERROR]: Failed to get kern.version via sysctl.\n");
exit(-1);
}
printf("[INFO]: Kernel = %s\n", kern_vers);
#ifdef __arm64__
if (strcasestr(kern_vers, "s5L8960x")) {
PHYS_OFF = S5l8960_PHYS_OFF;
phys_addr_remap = 0x83d100000;
} else if (strcasestr(kern_vers, "t7000")) {
PHYS_OFF = T7000_PHYS_OFF;
phys_addr_remap = 0x83eb00000;
} else if (strcasestr(kern_vers, "t7001")) {
PHYS_OFF = T7000_PHYS_OFF;
phys_addr_remap = 0x85eb00000;
} else {
printf("[ERROR]: Can't recognize the device.\n");
exit(-1);
}
#elif __arm__
if (strcasestr(kern_vers, "s5l8930x")) {
PHYS_OFF = S5L8930_PHYS_OFF;
phys_addr_remap = 0x5fe00000; // We basically want to set an iBSS image.
} else if (strcasestr(kern_vers, "s5l8920x") || strcasestr(kern_vers, "s5l8922x")) {
PHYS_OFF = S5L8930_PHYS_OFF;
phys_addr_remap = 0x4fe00000;
} else if (strcasestr(kern_vers, "s5l8940x") || strcasestr(kern_vers, "s5l8942x") || strcasestr(kern_vers, "s5l8947x")) {
PHYS_OFF = S5L8940_PHYS_OFF;
phys_addr_remap = 0x9fe00000; // " "
} else if (strcasestr(kern_vers, "s5l8950x") || strcasestr(kern_vers, "s5l8955x") || strcasestr(kern_vers, "s5l8945x")) {
PHYS_OFF = S5L8940_PHYS_OFF;
phys_addr_remap = 0xbfe00000;
} else {
printf("[WARNING]: Can't recognize the device.\n");
printf(" Assuming you're on an 8940-class device. You are on your own.\n");
PHYS_OFF = S5L8940_PHYS_OFF;
phys_addr_remap = 0x9fe00000; // " "
}
#endif
/*
* Pedanticness; though it doesn't matter, after we quit the entire OS is gone lol
*/
free(kern_vers);
printf("[INFO]: physOff = 0x%08x, remap = 0x%08x\n", PHYS_OFF, phys_addr_remap);
sysctlbyname("kern.osrelease", NULL, &size, NULL, 0x0);
char *umu = malloc(size);
if (size) {
sysctlbyname("kern.osrelease", umu, &size, NULL, 0x0);
} else {
printf("[ERROR]: Failed to get kern.osrelease via sysctl.\n");
return -0x1;
}
uint64_t kernel_vers = strtoull(umu, NULL, 0x0);
kernel_task = get_kernel_task();
#ifdef __arm64__
if (kernel_vers >= 15)
kernel_base = get_kernel_base_plus(kernel_task, kernel_vers);
else
kernel_base = get_kernel_base(kernel_task, kernel_vers);
#elif __arm__
kernel_base = get_kernel_base(kernel_task, kernel_vers);
#endif
/*
* kill
*/
pointer_t buf;
vm_address_t addr = kernel_base + 0x1000, e = 0, sz = 0;
uint8_t *kernel_dump = malloc(KERNEL_DUMP_SIZE + 0x1000);
if (!kernel_dump) {
printf("[ERROR]: Failed to malloc memory for kernel dump.\n");
return -1;
}
while (addr < (kernel_base + KERNEL_DUMP_SIZE)) {
vm_read(kernel_task, addr, chunksize, &buf, (mach_msg_type_number_t *)&sz);
if (!buf || sz == 0)
continue;
uint8_t *z = (uint8_t *)buf;
addr += chunksize;
bcopy(z, kernel_dump + e, chunksize);
e += chunksize;
}
/*
* kernel dumped, now find pmap.
*/
uint32_t kernel_pmap = kernel_base + 0x1000 + find_pmap_location(kernel_base, (uint8_t *)kernel_dump, KERNEL_DUMP_SIZE);
printf("[INFO]: Kernel pmap is at 0x%08x\n", kernel_pmap);
/*
* Read for kernel_pmap, dereference it for pmap_store.
*/
vm_read(kernel_task, kernel_pmap, 2048, &buf, (mach_msg_type_number_t *)&sz);
vm_read(kernel_task, *(vm_address_t *)(buf), 2048, &buf, (mach_msg_type_number_t *)&sz);
/*
* We now have the struct. Let's copy it out to get the TTE base (we don't really need to do this
* as it should just remain constant. TTEs should be after ToKD.)
*/
pmap_partial_t *part = (pmap_partial_t *)buf;
uint32_t tte_virt = part->tte_virt;
uint32_t tte_phys = part->tte_phys;
printf("[INFO]: Kernel pmap: tte_virt = 0x%08x | tte_phys = 0x%08x\n", tte_virt, tte_phys);
if (PHYS_OFF != (tte_phys & ~0xFFFFFFF)) {
printf("[ERROR]: physOff 0x%08x should be 0x%08x.\n", PHYS_OFF, tte_phys & ~0xFFFFFFF);
return -1;
}
/*
* generate TTEs.
*/
generate_ttb_entries();
/*
* Now, we can start reading at the TTE base and start writing in the descriptors.
*/
uint32_t tte_off = SHADOWMAP_BEGIN_OFF;
vm_read(kernel_task, tte_virt + tte_off, 2048, &buf, (mach_msg_type_number_t *)&sz);
bcopy((char *)ttb_template_ptr + tte_off, (void *)buf, SHADOWMAP_SIZE);
vm_write(kernel_task, tte_virt + tte_off, buf, sz);
printf("[WARNING]: Kernel TTE entries written. System stability is no longer guaranteed.\n");
printf(" Security has also been reduced by an exponential factor. You have been warned.\n");
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
signal(SIGINT, SIG_IGN);
FILE *fd = fopen(argv[1], "rb");
if (!fd) {
printf("[ERROR]: Failed to open image file. Rebooting momentarily...\n");
sleep(3);
reboot(0);
}
fseek(fd, 0x0, SEEK_END);
int length = ftell(fd);
fseek(fd, 0x0, SEEK_SET);
void *image = malloc(length);
fread(image, length, 0x1, fd);
fclose(fd);
printf("[INFO]: Reading bootloader into buffer %p, length %d\n", image, length);
bcopy((void *)image, (void *)0x7fe00000, length);
if (*(uint32_t *)image == 'Img3') {
printf("[ERROR]: IMG3 files are not supported.\n");
exit(1);
}
if (!strcmp((const char *)image + 0x7, "IM4P")) {
printf("[ERROR]: IM4P / IMG4 files are not supported.\n");
exit(1);
}
if (*(uint32_t *)0x7fe00000 != 0xea00000e)
printf("[WARNING]: This doesn't seem like an ARM image. Continuing regardless...\n");
printf("[INFO]: Image information: %s\n", (char *)0x7fe00000 + 0x200);
printf("[INFO]: Image information: %s\n", (char *)0x7fe00000 + 0x240);
printf("[INFO]: Image information: %s\n", (char *)0x7fe00000 + 0x280);
free(image);
/*
* iBEC copied, we need to copy over the shellcode now.
*/
uint32_t sysent_common = 0x1000 + find_syscall0(kernel_base + 0x1000, (uint8_t *)kernel_dump, KERNEL_DUMP_SIZE) + SHADOWMAP_BEGIN;
printf("[INFO]: sysent_common_base = 0x%08x\n", sysent_common);
/*
* fuck evasi0n7
*/
if (*(uint32_t *)(sysent_common) == 0x0) {
printf("[INFO]: iOS 7 detected, adjusting base 0x%08x to 0x%08x\n", sysent_common, *(uint32_t *)(sysent_common));
sysent_common += 0x4;
if (*(uint32_t *)(sysent_common) == 0x0) {
printf("[ERROR]: Something is severely wrong. Rebooting momentarily...\n");
sleep(3);
reboot(0);
}
}
/*
* Set offsets.
*/
larm_init_tramp = 0x1000 + find_larm_init_tramp(kernel_base + 0x1000, (uint8_t *)kernel_dump, KERNEL_DUMP_SIZE) + SHADOWMAP_BEGIN;
kern_base = kernel_base;
kern_tramp_phys = phys_addr_remap;
#if 0
printf("[INFO]: larm_init_tramp = 0x%08x\n", larm_init_tramp);
bcopy(shellcode_begin, (void *)0x7f000c00, shellcode_end - shellcode_begin);
*(uint32_t *)sysent_common = 0x7f000c01;
printf("[INFO]: Running shellcode now.\n");
syscall(0);
#else
static uint32_t arm[2] = { 0xe51ff004, 0x0 };
arm[1] = phys_addr_remap;
// Requires D-cache writeback.
printf("[INFO]: tramp = %x | ", larm_init_tramp);