update, but I changed my mind

This commit is contained in:
comex 2011-01-05 14:52:13 -05:00
parent 37b634baf7
commit c47718fdac

56
dmini.c
View File

@ -33,33 +33,30 @@ addr_t find_kernel_ldm(struct binary *binary, uint32_t valid_conds) {
if(!(binary->dyld_mappings[i].sfm_init_prot & PROT_EXEC)) continue;
char *p = rangeconv(range).start;
for(addr_t addr = range.start; addr + 4 <= (range.start + range.size); my_valid_conds = valid_conds, addr = (addr + 0x1000) & ~0xfff) {
back:;
harmless:;
uint32_t val = *((uint32_t *) (p + (addr - range.start)));
uint32_t cond = ((val & 0xf0000000) >> 28);
bool harmless = false;
if(cond != 15 && 0 == (my_valid_conds & (3 << (2*cond)))) {
harmless = true;
} else if(!(val & 0xc000000)) { // data processing
uint32_t rd = (val & 0xf000) >> 12;
if(rd != 0 && rd != 15) {
harmless = true;
if(!(val & (1 << 20))) my_valid_conds = 0x1aaaaaaa; // AL known 1, others unknown
} else if(rd == 0) {
uint32_t op = ((val & 0x1f00000) >> 20);
if(op == 17 || op == 19 || op == 21 || op == 23) {
harmless = true;
my_valid_conds = 0x1aaaaaaa;
if((addr & 0xfff) != 0xffc) {
if(cond != 15 && 0 == (my_valid_conds & (3 << (2*cond)))) {
addr += 4; goto harmless;
} else if(!(val & 0xc000000)) { // data processing
uint32_t rd = (val & 0xf000) >> 12;
if(rd != 0 && rd != 15) {
if(!(val & (1 << 20))) my_valid_conds = 0x1aaaaaaa; // AL known 1, others unknown
addr += 4; goto harmless;
} else if(rd == 0) {
uint32_t op = ((val & 0x1f00000) >> 20);
if(op == 17 || op == 19 || op == 21 || op == 23) {
my_valid_conds = 0x1aaaaaaa;
addr += 4; goto harmless;
}
}
}
}
if(harmless) {
//printf("@ %08x: %08x is harmless (vc=%08x)\n", addr, val, my_valid_conds);
addr += 4;
goto back;
}
if(cond == 15 || (1u << (2*cond)) != (my_valid_conds & (3 << (2*cond)))) {
continue;
}
@ -67,15 +64,22 @@ addr_t find_kernel_ldm(struct binary *binary, uint32_t valid_conds) {
//printf("ready to test %08x @ %08x\n", val, addr);
bool ldmib;
if((val & 0xf9fa000) == 0x890a000) {
if((val & 0xf9f8000) == 0x8908000) {
ldmib = false;
} else if((val & 0xf9fa000) == 0x990a000) {
} else if((val & 0xf9f8000) == 0x9908000) {
ldmib = true;
} else {
continue;
}
//printf("%08x -> %08x (%s)\n", addr, val, ldmib ? "ib" : "ia");
uint32_t reglist = val & 0x1fff;
printf("%08x -> %08x (%s)\n", addr, val, ldmib ? "ib" : "ia");
uint32_t reglist = val & 0x7fff;
int ones = count_ones(reglist);
if(ldmib) ones--;
if(ones < 3 || ones > 5) continue;
// figure out
printf("%d\n", count_ones(reglist));
if(count_ones(reglist) != (ldmib ? 1 : 2)) continue;
//printf(":) %08x = %08x\n", addr, val);
return addr;
@ -107,6 +111,8 @@ void main_loop() {
} else if(mode == 3) {
b_dyldcache_load_macho(&binary, arg);
result = 0;
} else if(mode == 4) {
result = find_kernel_ldm(&binary, atoi(arg));
} else die("mode?");
printf("+ %x\n", result);
@ -167,11 +173,11 @@ int main(int argc, char **argv) {
return 0;
usage:
fprintf(stderr, "Usage: dmini [-c cache | -C] [-d dyld] [-k kc | -K"
fprintf(stderr, "Usage: dmini (-c cache | -C | -d dyld | -k kc | -K"
#ifdef IMG3_SUPPORT
" | -i kernel_img3 key iv"
#endif
"]\n");
")\n");
return 1;
}