/* Cydia Substrate - Powerful Code Insertion Platform
* Copyright (C) 2008-2011 Jay Freeman (saurik)
*/
/* GNU Lesser General Public License, Version 3 {{{ */
/*
* Substrate is free software: you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* Substrate 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 Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Substrate. If not, see .
**/
/* }}} */
#define SubstrateInternal
#include "And64InlineHook.hpp"
#include
#define _trace() do { \
MSLog(MSLogLevelNotice, "_trace(%u)", __LINE__); \
} while (false)
#if defined(__i386__) || defined(__x86_64__)
#include "hde64.h"
#endif
#include "SubstrateDebug.hpp"
#include "And64InlineHook.hpp"
#include "CydiaSubstrate.h"
#include
#include
#include
#ifdef __arm__
/* WebCore (ARM) PC-Relative:
X 1 ldr r*,[pc,r*] !=
2 fldd d*,[pc,#*]
X 5 str r*,[pc,r*] !=
8 flds s*,[pc,#*]
400 ldr r*,[pc,r*] ==
515 add r*, pc,r* ==
X 4790 ldr r*,[pc,#*] */
// x=0; while IFS= read -r line; do if [[ ${#line} -ne 0 && $line == +([^\;]): ]]; then x=2; elif [[ $line == ' +'* && $x -ne 0 ]]; then ((--x)); echo "$x${line}"; fi; done WebCore.pc
// grep pc WebCore.pc | cut -c 40- | sed -Ee 's/^ldr *(ip|r[0-9]*),\[pc,\#0x[0-9a-f]*\].*/ ldr r*,[pc,#*]/;s/^add *r[0-9]*,pc,r[0-9]*.*/ add r*, pc,r*/;s/^(st|ld)r *r([0-9]*),\[pc,r([0-9]*)\].*/ \1r r\2,[pc,r\3]/;s/^fld(s|d) *(s|d)[0-9]*,\[pc,#0x[0-9a-f]*].*/fld\1 \2*,[pc,#*]/' | sort | uniq -c | sort -n
#include "SubstrateARM.hpp"
#include "And64InlineHook.hpp"
#define T$Label(l, r) \
(((r) - (l)) * 2 - 4 + ((l) % 2 == 0 ? 0 : 2))
#define T$pop_$r0$ 0xbc01 // pop {r0}
#define T$b(im) /* b im */ \
(0xde00 | (im & 0xff))
#define T$blx(rm) /* blx rm */ \
(0x4780 | (rm << 3))
#define T$bx(rm) /* bx rm */ \
(0x4700 | (rm << 3))
#define T$nop /* nop */ \
(0x46c0)
#define T$add_rd_rm(rd, rm) /* add rd, rm */ \
(0x4400 | (((rd) & 0x8) >> 3 << 7) | (((rm) & 0x8) >> 3 << 6) | (((rm) & 0x7) << 3) | ((rd) & 0x7))
#define T$push_r(r) /* push r... */ \
(0xb400 | (((r) & (1 << A$lr)) >> A$lr << 8) | ((r) & 0xff))
#define T$pop_r(r) /* pop r... */ \
(0xbc00 | (((r) & (1 << A$pc)) >> A$pc << 8) | ((r) & 0xff))
#define T$mov_rd_rm(rd, rm) /* mov rd, rm */ \
(0x4600 | (((rd) & 0x8) >> 3 << 7) | (((rm) & 0x8) >> 3 << 6) | (((rm) & 0x7) << 3) | ((rd) & 0x7))
#define T$ldr_rd_$rn_im_4$(rd, rn, im) /* ldr rd, [rn, #im * 4] */ \
(0x6800 | (((im) & 0x1f) << 6) | ((rn) << 3) | (rd))
#define T$ldr_rd_$pc_im_4$(rd, im) /* ldr rd, [PC, #im * 4] */ \
(0x4800 | ((rd) << 8) | ((im) & 0xff))
#define T$cmp_rn_$im(rn, im) /* cmp rn, #im */ \
(0x2000 | ((rn) << 8) | ((im) & 0xff))
#define T$it$_cd(cd, ms) /* it, cd */ \
(0xbf00 | ((cd) << 4) | (ms))
#define T$cbz$_rn_$im(op, rn, im) /* cbz rn, #im */ \
(0xb100 | ((op) << 11) | (((im) & 0x40) >> 6 << 9) | (((im) & 0x3e) >> 1 << 3) | (rn))
#define T$b$_$im(cond, im) /* b #im */ \
(cond == A$al ? 0xe000 | (((im) >> 1) & 0x7ff) : 0xd000 | ((cond) << 8) | (((im) >> 1) & 0xff))
#define T1$ldr_rt_$rn_im$(rt, rn, im) /* ldr rt, [rn, #im] */ \
(0xf850 | ((im < 0 ? 0 : 1) << 7) | (rn))
#define T2$ldr_rt_$rn_im$(rt, rn, im) /* ldr rt, [rn, #im] */ \
(((rt) << 12) | _abs(im))
#define T1$mrs_rd_apsr(rd) /* mrs rd, apsr */ \
(0xf3ef)
#define T2$mrs_rd_apsr(rd) /* mrs rd, apsr */ \
(0x8000 | ((rd) << 8))
#define T1$msr_apsr_nzcvqg_rn(rn) /* msr apsr, rn */ \
(0xf380 | (rn))
#define T2$msr_apsr_nzcvqg_rn(rn) /* msr apsr, rn */ \
(0x8c00)
#define T$msr_apsr_nzcvqg_rn(rn) /* msr apsr, rn */ \
(T2$msr_apsr_nzcvqg_rn(rn) << 16 | T1$msr_apsr_nzcvqg_rn(rn))
static inline bool A$pcrel$r(uint32_t ic) {
return (ic & 0x0c000000) == 0x04000000 && (ic & 0xf0000000) != 0xf0000000 &&
(ic & 0x000f0000) == 0x000f0000;
}
static inline bool T$32bit$i(uint16_t ic) {
return ((ic & 0xe000) == 0xe000 && (ic & 0x1800) != 0x0000);
}
static inline bool T$pcrel$cbz(uint16_t ic) {
return (ic & 0xf500) == 0xb100;
}
static inline bool T$pcrel$b(uint16_t ic) {
return (ic & 0xf000) == 0xd000 && (ic & 0x0e00) != 0x0e00;
}
static inline bool T2$pcrel$b(uint16_t *ic) {
return (ic[0] & 0xf800) == 0xf000 &&
((ic[1] & 0xd000) == 0x9000 || ((ic[1] & 0xd000) == 0x8000 && (ic[0] & 0x0380) != 0x0380));
}
static inline bool T$pcrel$bl(uint16_t *ic) {
return (ic[0] & 0xf800) == 0xf000 && ((ic[1] & 0xd000) == 0xd000 || (ic[1] & 0xd001) == 0xc000);
}
static inline bool T$pcrel$ldr(uint16_t ic) {
return (ic & 0xf800) == 0x4800;
}
static inline bool T$pcrel$add(uint16_t ic) {
return (ic & 0xff78) == 0x4478;
}
static inline bool T$pcrel$ldrw(uint16_t ic) {
return (ic & 0xff7f) == 0xf85f;
}
static size_t MSGetInstructionWidthThumb(void *start) {
uint16_t *thumb(reinterpret_cast(start));
return T$32bit$i(thumb[0]) ? 4 : 2;
}
static size_t MSGetInstructionWidthARM(void *start) {
return 4;
}
extern "C" size_t MSGetInstructionWidth(void *start) {
if ((reinterpret_cast(start) & 0x1) == 0)
return MSGetInstructionWidthARM(start);
else
return MSGetInstructionWidthThumb(
reinterpret_cast(reinterpret_cast(start) & ~0x1));
}
static size_t SubstrateHookFunctionThumb(SubstrateProcessRef process, void *symbol, void *replace,
void **result) {
if (symbol == NULL)
return 0;
printf("SubstrateHookFunctionThumb\n");
uint16_t *area(reinterpret_cast(symbol));
unsigned align((reinterpret_cast(area) & 0x2) == 0 ? 0 : 1);
uint16_t *thumb(area + align);
uint32_t *arm(reinterpret_cast(thumb + 2));
uint16_t *trail(reinterpret_cast(arm + 2));
if (
(align == 0 || area[0] == T$nop) &&
thumb[0] == T$bx(A$pc) &&
thumb[1] == T$nop &&
arm[0] == A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8)
) {
if (result != NULL)
*result = reinterpret_cast(arm[1]);
SubstrateHookMemory code(process, arm + 1, sizeof(uint32_t) * 1);
arm[1] = reinterpret_cast(replace);
return sizeof(arm[0]);
}
size_t required((trail - area) * sizeof(uint16_t));
size_t used(0);
while (used < required)
used += MSGetInstructionWidthThumb(reinterpret_cast(area) + used);
used = (used + sizeof(uint16_t) - 1) / sizeof(uint16_t) * sizeof(uint16_t);
size_t blank((used - required) / sizeof(uint16_t));
uint16_t backup[used / sizeof(uint16_t)];
memcpy(backup, area, used);
if (MSDebug) {
char name[16];
sprintf(name, "%p", area);
MSLogHexEx(area, used + sizeof(uint16_t), 2, name);
}
if (result != NULL) {
size_t length(used);
for (unsigned offset(0); offset != used / sizeof(uint16_t); ++offset)
if (T$pcrel$ldr(backup[offset]))
length += 3 * sizeof(uint16_t);
else if (T$pcrel$b(backup[offset]))
length += 6 * sizeof(uint16_t);
else if (T2$pcrel$b(backup + offset)) {
length += 5 * sizeof(uint16_t);
++offset;
} else if (T$pcrel$bl(backup + offset)) {
length += 5 * sizeof(uint16_t);
++offset;
} else if (T$pcrel$cbz(backup[offset])) {
length += 16 * sizeof(uint16_t);
} else if (T$pcrel$ldrw(backup[offset])) {
length += 4 * sizeof(uint16_t);
++offset;
} else if (T$pcrel$add(backup[offset]))
length += 6 * sizeof(uint16_t);
else if (T$32bit$i(backup[offset]))
++offset;
unsigned pad((length & 0x2) == 0 ? 0 : 1);
length += (pad + 2) * sizeof(uint16_t) + 2 * sizeof(uint32_t);
uint16_t *buffer(reinterpret_cast(mmap(
NULL, length, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0
)));
if (buffer == MAP_FAILED) {
MSLog(MSLogLevelError, "MS:Error:mmap() = %d", errno);
*result = NULL;
return 0;
}
if (false)
fail:
{
munmap(buffer, length);
*result = NULL;
return 0;
}
size_t start(pad), end(length / sizeof(uint16_t));
uint32_t *trailer(reinterpret_cast(buffer + end));
for (unsigned offset(0); offset != used / sizeof(uint16_t); ++offset) {
if (T$pcrel$ldr(backup[offset])) {
union {
uint16_t value;
struct {
uint16_t immediate : 8;
uint16_t rd : 3;
uint16_t : 5;
};
} bits = {backup[offset + 0]};
buffer[start + 0] = T$ldr_rd_$pc_im_4$(bits.rd, T$Label(start + 0, end - 2) / 4);
buffer[start + 1] = T$ldr_rd_$rn_im_4$(bits.rd, bits.rd, 0);
// XXX: this code "works", but is "wrong": the mechanism is more complex than this
*--trailer = ((reinterpret_cast(area + offset) + 4) & ~0x2) +
bits.immediate * 4;
start += 2;
end -= 2;
} else if (T$pcrel$b(backup[offset])) {
union {
uint16_t value;
struct {
uint16_t imm8 : 8;
uint16_t cond : 4;
uint16_t /*1101*/ : 4;
};
} bits = {backup[offset + 0]};
intptr_t jump(bits.imm8 << 1);
jump |= 1;
jump <<= 23;
jump >>= 23;
buffer[start + 0] = T$b$_$im(bits.cond, (end - 6 - (start + 0)) * 2 - 4);
*--trailer = reinterpret_cast(area + offset) + 4 + jump;
*--trailer = A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8);
*--trailer = T$nop << 16 | T$bx(A$pc);
start += 1;
end -= 6;
} else if (T2$pcrel$b(backup + offset)) {
union {
uint16_t value;
struct {
uint16_t imm6 : 6;
uint16_t cond : 4;
uint16_t s : 1;
uint16_t : 5;
};
} bits = {backup[offset + 0]};
union {
uint16_t value;
struct {
uint16_t imm11 : 11;
uint16_t j2 : 1;
uint16_t a : 1;
uint16_t j1 : 1;
uint16_t : 2;
};
} exts = {backup[offset + 1]};
intptr_t jump(1);
jump |= exts.imm11 << 1;
jump |= bits.imm6 << 12;
if (exts.a) {
jump |= bits.s << 24;
jump |= (~(bits.s ^ exts.j1) & 0x1) << 23;
jump |= (~(bits.s ^ exts.j2) & 0x1) << 22;
jump |= bits.cond << 18;
jump <<= 7;
jump >>= 7;
} else {
jump |= bits.s << 20;
jump |= exts.j2 << 19;
jump |= exts.j1 << 18;
jump <<= 11;
jump >>= 11;
}
buffer[start + 0] = T$b$_$im(exts.a ? A$al : bits.cond,
(end - 6 - (start + 0)) * 2 - 4);
*--trailer = reinterpret_cast(area + offset) + 4 + jump;
*--trailer = A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8);
*--trailer = T$nop << 16 | T$bx(A$pc);
++offset;
start += 1;
end -= 6;
} else if (T$pcrel$bl(backup + offset)) {
union {
uint16_t value;
struct {
uint16_t immediate : 10;
uint16_t s : 1;
uint16_t : 5;
};
} bits = {backup[offset + 0]};
union {
uint16_t value;
struct {
uint16_t immediate : 11;
uint16_t j2 : 1;
uint16_t x : 1;
uint16_t j1 : 1;
uint16_t : 2;
};
} exts = {backup[offset + 1]};
int32_t jump(0);
jump |= bits.s << 24;
jump |= (~(bits.s ^ exts.j1) & 0x1) << 23;
jump |= (~(bits.s ^ exts.j2) & 0x1) << 22;
jump |= bits.immediate << 12;
jump |= exts.immediate << 1;
jump |= exts.x;
jump <<= 7;
jump >>= 7;
buffer[start + 0] = T$push_r(1 << A$r7);
buffer[start + 1] = T$ldr_rd_$pc_im_4$(A$r7,
((end - 2 - (start + 1)) * 2 - 4 + 2) / 4);
buffer[start + 2] = T$mov_rd_rm(A$lr, A$r7);
buffer[start + 3] = T$pop_r(1 << A$r7);
buffer[start + 4] = T$blx(A$lr);
*--trailer = reinterpret_cast(area + offset) + 4 + jump;
++offset;
start += 5;
end -= 2;
} else if (T$pcrel$cbz(backup[offset])) {
union {
uint16_t value;
struct {
uint16_t rn : 3;
uint16_t immediate : 5;
uint16_t : 1;
uint16_t i : 1;
uint16_t : 1;
uint16_t op : 1;
uint16_t : 4;
};
} bits = {backup[offset + 0]};
intptr_t jump(1);
jump |= bits.i << 6;
jump |= bits.immediate << 1;
//jump <<= 24;
//jump >>= 24;
unsigned rn(bits.rn);
unsigned rt(rn == A$r7 ? A$r6 : A$r7);
buffer[start + 0] = T$push_r(1 << rt);
buffer[start + 1] = T1$mrs_rd_apsr(rt);
buffer[start + 2] = T2$mrs_rd_apsr(rt);
buffer[start + 3] = T$cbz$_rn_$im(bits.op, rn, (end - 10 - (start + 3)) * 2 - 4);
buffer[start + 4] = T1$msr_apsr_nzcvqg_rn(rt);
buffer[start + 5] = T2$msr_apsr_nzcvqg_rn(rt);
buffer[start + 6] = T$pop_r(1 << rt);
*--trailer = reinterpret_cast(area + offset) + 4 + jump;
*--trailer = A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8);
*--trailer = T$nop << 16 | T$bx(A$pc);
*--trailer = T$nop << 16 | T$pop_r(1 << rt);
*--trailer = T$msr_apsr_nzcvqg_rn(rt);
#if 0
if ((start & 0x1) == 0)
buffer[start++] = T$nop;
buffer[start++] = T$bx(A$pc);
buffer[start++] = T$nop;
uint32_t *arm(reinterpret_cast(buffer + start));
arm[0] = A$add(A$lr, A$pc, 1);
arm[1] = A$ldr_rd_$rn_im$(A$pc, A$pc, (trailer - arm) * sizeof(uint32_t) - 8);
#endif
start += 7;
end -= 10;
} else if (T$pcrel$ldrw(backup[offset])) {
union {
uint16_t value;
struct {
uint16_t : 7;
uint16_t u : 1;
uint16_t : 8;
};
} bits = {backup[offset + 0]};
union {
uint16_t value;
struct {
uint16_t immediate : 12;
uint16_t rt : 4;
};
} exts = {backup[offset + 1]};
buffer[start + 0] = T1$ldr_rt_$rn_im$(exts.rt, A$pc, T$Label(start + 0, end - 2));
buffer[start + 1] = T2$ldr_rt_$rn_im$(exts.rt, A$pc, T$Label(start + 0, end - 2));
buffer[start + 2] = T1$ldr_rt_$rn_im$(exts.rt, exts.rt, 0);
buffer[start + 3] = T2$ldr_rt_$rn_im$(exts.rt, exts.rt, 0);
// XXX: this code "works", but is "wrong": the mechanism is more complex than this
*--trailer = ((reinterpret_cast(area + offset) + 4) & ~0x2) +
(bits.u == 0 ? -exts.immediate : exts.immediate);
++offset;
start += 4;
end -= 2;
} else if (T$pcrel$add(backup[offset])) {
union {
uint16_t value;
struct {
uint16_t rd : 3;
uint16_t rm : 3;
uint16_t h2 : 1;
uint16_t h1 : 1;
uint16_t : 8;
};
} bits = {backup[offset + 0]};
if (bits.h1) {
MSLog(MSLogLevelError, "MS:Error:pcrel(%u):add (rd > r7)", offset);
goto fail;
}
unsigned rt(bits.rd == A$r7 ? A$r6 : A$r7);
buffer[start + 0] = T$push_r(1 << rt);
buffer[start + 1] = T$mov_rd_rm(rt, (bits.h1 << 3) | bits.rd);
buffer[start + 2] = T$ldr_rd_$pc_im_4$(bits.rd, T$Label(start + 2, end - 2) / 4);
buffer[start + 3] = T$add_rd_rm((bits.h1 << 3) | bits.rd, rt);
buffer[start + 4] = T$pop_r(1 << rt);
*--trailer = reinterpret_cast(area + offset) + 4;
start += 5;
end -= 2;
} else if (T$32bit$i(backup[offset])) {
buffer[start++] = backup[offset];
buffer[start++] = backup[++offset];
} else {
buffer[start++] = backup[offset];
}
}
buffer[start++] = T$bx(A$pc);
buffer[start++] = T$nop;
uint32_t *transfer = reinterpret_cast(buffer + start);
transfer[0] = A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8);
transfer[1] = reinterpret_cast(area + used / sizeof(uint16_t)) + 1;
if (mprotect(buffer, length, PROT_READ | PROT_EXEC) == -1) {
MSLog(MSLogLevelError, "MS:Error:mprotect():%d", errno);
return 0;
}
*result = reinterpret_cast(buffer + pad) + 1;
if (MSDebug) {
char name[16];
sprintf(name, "%p", *result);
MSLogHexEx(buffer, length, 2, name);
}
}
{
SubstrateHookMemory code(process, area, used);
if (align != 0)
area[0] = T$nop;
thumb[0] = T$bx(A$pc);
thumb[1] = T$nop;
arm[0] = A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8);
arm[1] = reinterpret_cast(replace);
for (unsigned offset(0); offset != blank; ++offset)
trail[offset] = T$nop;
}
if (MSDebug) {
char name[16];
sprintf(name, "%p", area);
MSLogHexEx(area, used + sizeof(uint16_t), 2, name);
}
return used;
}
static size_t
SubstrateHookFunctionARM(SubstrateProcessRef process, void *symbol, void *replace, void **result) {
if (symbol == NULL)
return 0;
printf("SubstrateHookFunctionARM\n");
uint32_t *area(reinterpret_cast(symbol));
uint32_t *arm(area);
const size_t used(8);
uint32_t backup[used / sizeof(uint32_t)] = {arm[0], arm[1]};
if (MSDebug) {
char name[16];
sprintf(name, "%p", area);
MSLogHexEx(area, used + sizeof(uint32_t), 4, name);
}
if (result != NULL) {
if (backup[0] == A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8)) {
*result = reinterpret_cast(backup[1]);
return sizeof(backup[0]);
}
size_t length(used);
for (unsigned offset(0); offset != used / sizeof(uint32_t); ++offset)
if (A$pcrel$r(backup[offset])) {
if ((backup[offset] & 0x02000000) == 0 ||
(backup[offset] & 0x0000f000 >> 12) != (backup[offset] & 0x0000000f))
length += 2 * sizeof(uint32_t);
else
length += 4 * sizeof(uint32_t);
}
length += 2 * sizeof(uint32_t);
uint32_t *buffer(reinterpret_cast(mmap(
NULL, length, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0
)));
if (buffer == MAP_FAILED) {
MSLog(MSLogLevelError, "MS:Error:mmap() = %d", errno);
*result = NULL;
return 0;
}
if (false)
fail:
{
munmap(buffer, length);
*result = NULL;
return 0;
}
size_t start(0), end(length / sizeof(uint32_t));
uint32_t *trailer(reinterpret_cast(buffer + end));
for (unsigned offset(0); offset != used / sizeof(uint32_t); ++offset)
if (A$pcrel$r(backup[offset])) {
union {
uint32_t value;
struct {
uint32_t rm : 4;
uint32_t : 1;
uint32_t shift : 2;
uint32_t shiftamount : 5;
uint32_t rd : 4;
uint32_t rn : 4;
uint32_t l : 1;
uint32_t w : 1;
uint32_t b : 1;
uint32_t u : 1;
uint32_t p : 1;
uint32_t mode : 1;
uint32_t type : 2;
uint32_t cond : 4;
};
} bits = {backup[offset + 0]}, copy(bits);
bool guard;
if (bits.mode == 0 || bits.rd != bits.rm) {
copy.rn = bits.rd;
guard = false;
} else {
copy.rn = bits.rm != A$r0 ? A$r0 : A$r1;
guard = true;
}
if (guard)
buffer[start++] = A$stmdb_sp$_$rs$((1 << copy.rn));
buffer[start + 0] = A$ldr_rd_$rn_im$(copy.rn, A$pc,
(end - 1 - (start + 0)) * 4 - 8);
buffer[start + 1] = copy.value;
start += 2;
if (guard)
buffer[start++] = A$ldmia_sp$_$rs$((1 << copy.rn));
*--trailer = reinterpret_cast(area + offset) + 8;
end -= 1;
} else
buffer[start++] = backup[offset];
buffer[start + 0] = A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8);
buffer[start + 1] = reinterpret_cast(area + used / sizeof(uint32_t));
if (mprotect(buffer, length, PROT_READ | PROT_EXEC) == -1) {
MSLog(MSLogLevelError, "MS:Error:mprotect():%d", errno);
goto fail;
}
*result = buffer;
if (MSDebug) {
char name[16];
sprintf(name, "%p", *result);
MSLogHexEx(buffer, length, 4, name);
}
}
{
SubstrateHookMemory code(process, symbol, used);
arm[0] = A$ldr_rd_$rn_im$(A$pc, A$pc, 4 - 8);
arm[1] = reinterpret_cast(replace);
}
if (MSDebug) {
char name[16];
sprintf(name, "%p", area);
MSLogHexEx(area, used + sizeof(uint32_t), 4, name);
}
return used;
}
static size_t
SubstrateHookFunction(SubstrateProcessRef process, void *symbol, void *replace, void **result) {
if (MSDebug)
MSLog(MSLogLevelNotice, "SubstrateHookFunction(%p, %p, %p, %p)\n", process, symbol, replace,
result);
if ((reinterpret_cast(symbol) & 0x1) == 0)
return SubstrateHookFunctionARM(process, symbol, replace, result);
else
return SubstrateHookFunctionThumb(process, reinterpret_cast(
reinterpret_cast(symbol) & ~0x1), replace, result);
}
#endif
#if defined(__i386__) || defined(__x86_64__)
#include "SubstrateX86.hpp"
static size_t MSGetInstructionWidthIntel(void *start) {
hde64s decode;
return hde64_disasm(start, &decode);
}
static void SubstrateHookFunction(SubstrateProcessRef process, void *symbol, void *replace, void **result) {
if (MSDebug)
MSLog(MSLogLevelNotice, "MSHookFunction(%p, %p, %p)\n", symbol, replace, result);
if (symbol == NULL)
return;
uintptr_t source(reinterpret_cast(symbol));
uintptr_t target(reinterpret_cast(replace));
uint8_t *area(reinterpret_cast(symbol));
size_t required(MSSizeOfJump(target, source));
if (MSDebug) {
char name[16];
sprintf(name, "%p", area);
MSLogHex(area, 32, name);
}
size_t used(0);
while (used < required) {
size_t width(MSGetInstructionWidthIntel(area + used));
if (width == 0) {
MSLog(MSLogLevelError, "MS:Error:MSGetInstructionWidthIntel(%p) == 0", area + used);
return;
}
used += width;
}
size_t blank(used - required);
if (MSDebug) {
char name[16];
sprintf(name, "%p", area);
MSLogHex(area, used + sizeof(uint16_t), name);
}
uint8_t backup[used];
memcpy(backup, area, used);
if (result != NULL) {
if (backup[0] == 0xe9) {
*result = reinterpret_cast(source + 5 + *reinterpret_cast(backup + 1));
return;
}
if (!ia32 && backup[0] == 0xff && backup[1] == 0x25) {
*result = *reinterpret_cast(source + 6 + *reinterpret_cast(backup + 2));
return;
}
size_t length(used + MSSizeOfJump(source + used));
for (size_t offset(0), width; offset != used; offset += width) {
hde64s decode;
hde64_disasm(backup + offset, &decode);
width = decode.len;
//_assert(width != 0 && offset + width <= used);
#ifdef __LP64__
if ((decode.modrm & 0xc7) == 0x05) {
if (decode.opcode == 0x8b) {
void *destiny(area + offset + width + int32_t(decode.disp.disp32));
uint8_t reg(decode.rex_r << 3 | decode.modrm_reg);
length -= decode.len;
length += MSSizeOfPushPointer(destiny);
length += MSSizeOfPop(reg);
length += MSSizeOfMove64();
} else {
MSLog(MSLogLevelError, "MS:Error: Unknown RIP-Relative (%.2x %.2x)", decode.opcode, decode.opcode2);
continue;
}
} else
#endif
if (backup[offset] == 0xe8) {
int32_t relative(*reinterpret_cast(backup + offset + 1));
void *destiny(area + offset + decode.len + relative);
if (relative == 0) {
length -= decode.len;
length += MSSizeOfPushPointer(destiny);
} else {
length += MSSizeOfSkip();
length += MSSizeOfJump(destiny);
}
} else if (backup[offset] == 0xeb) {
length -= decode.len;
length += MSSizeOfJump(area + offset + decode.len + *reinterpret_cast(backup + offset + 1));
} else if (backup[offset] == 0xe9) {
length -= decode.len;
length += MSSizeOfJump(area + offset + decode.len + *reinterpret_cast(backup + offset + 1));
} else if (
backup[offset] == 0xe3 ||
(backup[offset] & 0xf0) == 0x70
// XXX: opcode2 & 0xf0 is 0x80?
) {
length += decode.len;
length += MSSizeOfJump(area + offset + decode.len + *reinterpret_cast(backup + offset + 1));
}
}
uint8_t *buffer(reinterpret_cast(mmap(
NULL, length, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0
)));
if (buffer == MAP_FAILED) {
MSLog(MSLogLevelError, "MS:Error:mmap() = %d", errno);
*result = NULL;
return;
}
if (false) fail: {
munmap(buffer, length);
*result = NULL;
return;
}
{
uint8_t *current(buffer);
for (size_t offset(0), width; offset != used; offset += width) {
hde64s decode;
hde64_disasm(backup + offset, &decode);
width = decode.len;
//_assert(width != 0 && offset + width <= used);
#ifdef __LP64__
if ((decode.modrm & 0xc7) == 0x05) {
if (decode.opcode == 0x8b) {
void *destiny(area + offset + width + int32_t(decode.disp.disp32));
uint8_t reg(decode.rex_r << 3 | decode.modrm_reg);
MSPushPointer(current, destiny);
MSWritePop(current, reg);
MSWriteMove64(current, reg, reg);
} else {
MSLog(MSLogLevelError, "MS:Error: Unknown RIP-Relative (%.2x %.2x)", decode.opcode, decode.opcode2);
goto copy;
}
} else
#endif
if (backup[offset] == 0xe8) {
int32_t relative(*reinterpret_cast(backup + offset + 1));
if (relative == 0)
MSPushPointer(current, area + offset + decode.len);
else {
MSWrite(current, 0xe8);
MSWrite(current, MSSizeOfSkip());
void *destiny(area + offset + decode.len + relative);
MSWriteSkip(current, MSSizeOfJump(destiny, current + MSSizeOfSkip()));
MSWriteJump(current, destiny);
}
} else if (backup[offset] == 0xeb)
MSWriteJump(current, area + offset + decode.len + *reinterpret_cast(backup + offset + 1));
else if (backup[offset] == 0xe9)
MSWriteJump(current, area + offset + decode.len + *reinterpret_cast(backup + offset + 1));
else if (
backup[offset] == 0xe3 ||
(backup[offset] & 0xf0) == 0x70
) {
MSWrite(current, backup[offset]);
MSWrite(current, 2);
MSWrite(current, 0xeb);
void *destiny(area + offset + decode.len + *reinterpret_cast(backup + offset + 1));
MSWrite(current, MSSizeOfJump(destiny, current + 1));
MSWriteJump(current, destiny);
} else
#ifdef __LP64__
copy:
#endif
{
MSWrite(current, backup + offset, width);
}
}
MSWriteJump(current, area + used);
}
if (mprotect(buffer, length, PROT_READ | PROT_EXEC) == -1) {
MSLog(MSLogLevelError, "MS:Error:mprotect():%d", errno);
goto fail;
}
*result = buffer;
if (MSDebug) {
char name[16];
sprintf(name, "%p", *result);
MSLogHex(buffer, length, name);
}
}
{
SubstrateHookMemory code(process, area, used);
uint8_t *current(area);
MSWriteJump(current, target);
for (unsigned offset(0); offset != blank; ++offset)
MSWrite(current, 0x90);
}
if (MSDebug) {
char name[16];
sprintf(name, "%p", area);
MSLogHex(area, used + sizeof(uint16_t), name);
}
}
#endif
_extern void MSHookFunction(void *symbol, void *replace, void **result) {
#ifdef __aarch64__
A64HookFunction(symbol, replace, result);
#else
SubstrateHookFunction(NULL, symbol, replace, result);
#endif
}
#if defined(__APPLE__) && defined(__arm__)
_extern void _Z14MSHookFunctionPvS_PS_(void *symbol, void *replace, void **result) {
return MSHookFunction(symbol, replace, result);
}
#endif