#include #include #include #include static int count = 1; bool cb_hookunmapped(uc_engine *uc, uc_mem_type type, uint64_t address, uint32_t size, int64_t value, void *user_data) { uint32_t pc = 0; uc_reg_read(uc, UC_X86_REG_EIP, &pc); fprintf(stderr, "mem unmapped: 0x%x type: %x address: 0x%"PRIx64" length: %x value: 0x%"PRIx64"\n", pc, type, address, size, value); uc_err err = UC_ERR_OK; err = uc_emu_stop(uc); if (err != UC_ERR_OK) { fprintf(stderr, "stop not ok"); exit(0); } return true; } // move esi, dword ptr [ecx + eax + 0x28] // add esi, eax // lea eax, dword ptr [ebp - 4] // push eax // push 0x40 // push 0x10 // push esi // call some address #define CODE "\x8B\x74\x01\x28" \ "\x0C\xF0" \ "\x8D\x45\xFC" \ "\x50" \ "\x6A\x40" \ "\x6A\x10" \ "\x56" \ "\xFF\x15\x20\x20\x00\x10" int main() { uc_engine *uc; uc_err err = uc_open(UC_ARCH_X86, UC_MODE_32, &uc); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_open\n", count++); err = uc_mem_map(uc, 0x1000, 0x1000, UC_PROT_ALL); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_mem_map: code\n", count++); uint8_t code[0x1000]; memset(code, 0x0, sizeof(code)); memcpy(code, CODE, sizeof(CODE)); err = uc_mem_write(uc, 0x1000, code, sizeof(code)); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_mem_write: code\n", count++); uint32_t eip = 0x1000; err = uc_reg_write(uc, UC_X86_REG_EIP, &eip); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_reg_write: eip\n", count++); err = uc_mem_map(uc, 0x4000, 0x4000, UC_PROT_ALL); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_mem_map: stack\n", count++); uint8_t stack[0x4000]; memset(stack, 0x0, sizeof(stack)); err = uc_mem_write(uc, 0x4000, code, sizeof(code)); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_mem_write: stack\n", count++); uint32_t esp = 0x6000; err = uc_reg_write(uc, UC_X86_REG_ESP, &esp); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_reg_write: esp\n", count++); uint32_t ebp = 0x6000; err = uc_reg_write(uc, UC_X86_REG_EBP, &ebp); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_reg_write: ebp\n", count++); uc_hook h1; err = uc_hook_add(uc, &h1, UC_HOOK_MEM_UNMAPPED, cb_hookunmapped, NULL, 1, 0); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_hook_add\n", count++); // this should execute only a single instruction at 0x1000, because // that instruction accesses invalid memory. err = uc_emu_start(uc, 0x1000, 0x100F, 0, 0); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_emu_start\n", count++); // yes, not necessary, but to demonstrate the UC API is working as expected eip = 0x1004; err = uc_reg_write(uc, UC_X86_REG_EIP, &eip); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_reg_write: eip\n", count++); // this should execute the remaining instructions up to (but not includign) 0x100F. // currently, it returns an error about an unmapped read. // seems that this error should have been returned in the previous call // to emu_start. err = uc_emu_start(uc, 0x1004, 0x100F, 0, 0); if (err != UC_ERR_OK) { fprintf(stderr, "not ok %d - %s\n", count++, uc_strerror(err)); exit(0); } fprintf(stderr, "ok %d - uc_emu_start\n", count++); fprintf(stderr, "ok %d - Done", count++); return 0; }