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595 lines
22 KiB
595 lines
22 KiB
#include <string>
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#include <vmemu_t.hpp>
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namespace vm {
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emu_t::emu_t(vm::vmctx_t* vm_ctx) : m_vm(vm_ctx) {}
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emu_t::~emu_t() {
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if (uc) uc_close(uc);
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}
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bool emu_t::init() {
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uc_err err;
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if ((err = uc_open(UC_ARCH_X86, UC_MODE_64, &uc))) {
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std::printf("> uc_open err = %d\n", err);
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return false;
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}
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if ((err = uc_mem_map(uc, STACK_BASE, STACK_SIZE, UC_PROT_ALL))) {
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std::printf("> uc_mem_map stack err, reason = %d\n", err);
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return false;
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}
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if ((err = uc_mem_map(uc, m_vm->m_module_base, m_vm->m_image_size,
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UC_PROT_ALL))) {
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std::printf("> map memory failed, reason = %d\n", err);
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return false;
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}
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if ((err = uc_mem_write(uc, m_vm->m_module_base,
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reinterpret_cast<void*>(m_vm->m_module_base),
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m_vm->m_image_size))) {
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std::printf("> failed to write memory... reason = %d\n", err);
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return false;
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}
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if ((err = uc_hook_add(uc, &code_exec_hook, UC_HOOK_CODE,
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(void*)&vm::emu_t::code_exec_callback, this,
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m_vm->m_module_base,
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m_vm->m_module_base + m_vm->m_image_size))) {
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std::printf("> uc_hook_add error, reason = %d\n", err);
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return false;
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}
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if ((err = uc_hook_add(uc, &int_hook, UC_HOOK_INTR,
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(void*)&vm::emu_t::int_callback, this, 0ull, 0ull))) {
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std::printf("> uc_hook_add error, reason = %d\n", err);
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return false;
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}
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if ((err =
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uc_hook_add(uc, &invalid_mem_hook,
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UC_HOOK_MEM_READ_UNMAPPED | UC_HOOK_MEM_WRITE_UNMAPPED |
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UC_HOOK_MEM_FETCH_UNMAPPED,
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(void*)&vm::emu_t::invalid_mem, this, true, false))) {
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std::printf("> uc_hook_add error, reason = %d\n", err);
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return false;
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}
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return true;
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}
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bool emu_t::emulate(std::uint32_t vmenter_rva, vm::instrs::vrtn_t& vrtn) {
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uc_err err;
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vrtn.m_rva = vmenter_rva;
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auto& blk = vrtn.m_blks.emplace_back();
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blk.m_vip = {0ull, 0ull};
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blk.m_vm = {m_vm->get_vip(), m_vm->get_vsp()};
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cc_blk = &blk;
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cc_vrtn = &vrtn;
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cc_trace.m_uc = uc;
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std::uintptr_t rip = vmenter_rva + m_vm->m_module_base,
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rsp = STACK_BASE + STACK_SIZE - PAGE_4KB;
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if ((err = uc_reg_write(uc, UC_X86_REG_RSP, &rsp))) {
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std::printf("> uc_reg_write error, reason = %d\n", err);
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return false;
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}
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if ((err = uc_reg_write(uc, UC_X86_REG_RIP, &rip))) {
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std::printf("> uc_reg_write error, reason = %d\n", err);
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return false;
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}
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cc_trace.m_vip = cc_blk->m_vm.vip;
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cc_trace.m_vsp = cc_blk->m_vm.vsp;
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std::printf("> beginning execution at = %p\n", rip);
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if ((err = uc_emu_start(uc, rip, 0ull, 0ull, 0ull))) {
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std::printf("> error starting emu... reason = %d\n", err);
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return false;
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}
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extract_branch_data();
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std::printf("> emulated blk_%p\n\n", cc_blk->m_vip.img_base);
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// keep track of the emulated blocks... by their addresses...
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std::vector<std::uintptr_t> blk_addrs;
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blk_addrs.push_back(blk.m_vip.rva + m_vm->m_module_base);
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// the vector containing the vblk's grows inside of this for loop
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// thus we cannot use an advanced for loop (which uses itr's)...
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for (auto idx = 0u; idx < cc_vrtn->m_blks.size(); ++idx) {
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vm::instrs::vblk_t blk = cc_vrtn->m_blks[idx];
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if (blk.branch_type != vm::instrs::vbranch_type::none) {
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// force the emulation of all branches...
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for (const auto br : blk.branches) {
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// only emulate blocks that havent been emulated before...
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if (std::find(blk_addrs.begin(), blk_addrs.end(), br) !=
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blk_addrs.end())
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continue;
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std::uintptr_t vsp = 0ull;
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uc_context_restore(uc, blk.m_jmp.ctx);
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uc_mem_write(uc, STACK_BASE, blk.m_jmp.stack, STACK_SIZE);
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uc_reg_read(uc, vm::instrs::reg_map[blk.m_vm.vsp], &vsp);
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// setup new cc_blk...
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auto& new_blk = vrtn.m_blks.emplace_back();
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new_blk.m_vip = {0ull, 0ull};
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new_blk.m_vm = {blk.m_jmp.m_vm.vip, blk.m_jmp.m_vm.vsp};
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cc_blk = &new_blk;
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// emulate the branch...
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uc_mem_write(uc, vsp, &br, sizeof br);
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std::printf("> beginning execution at = %p\n", blk.m_jmp.rip);
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if ((err = uc_emu_start(uc, blk.m_jmp.rip, 0ull, 0ull, 0ull))) {
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std::printf("> error starting emu... reason = %d\n", err);
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return false;
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}
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extract_branch_data();
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std::printf("> emulated blk_%p\n", cc_blk->m_vip.img_base);
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}
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}
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}
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// free all virtual code block virtual jmp information...
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std::for_each(vrtn.m_blks.begin(), vrtn.m_blks.end(),
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[&](vm::instrs::vblk_t& blk) {
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if (blk.m_jmp.ctx) uc_context_free(blk.m_jmp.ctx);
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if (blk.m_jmp.stack) delete[] blk.m_jmp.stack;
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});
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return true;
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}
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void emu_t::extract_branch_data() {
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auto br_info = could_have_jcc(cc_blk->m_vinstrs);
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if (br_info.has_value()) {
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auto [br1, br2] = br_info.value();
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// convert to absolute addresses...
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br1 -= m_vm->m_image_base;
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br2 -= m_vm->m_image_base;
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br1 += m_vm->m_module_base;
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br2 += m_vm->m_module_base;
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auto br1_legit = legit_branch(*cc_blk, br1);
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auto br2_legit = legit_branch(*cc_blk, br2);
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std::printf("> br1 legit: %d, br2 legit: %d\n", br1_legit, br2_legit);
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if (br1_legit && br2_legit) {
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std::printf("> virtual jcc uncovered... br1 = %p, br2 = %p\n", br1, br2);
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cc_blk->branch_type = vm::instrs::vbranch_type::jcc;
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cc_blk->branches.push_back(br1);
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cc_blk->branches.push_back(br2);
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} else if (br1_legit || br2_legit) {
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std::printf("> absolute virtual jmp uncovered... branch = %p\n",
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br1_legit ? br1 : br2);
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cc_blk->branch_type = vm::instrs::vbranch_type::absolute;
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cc_blk->branches.push_back(br1_legit ? br1 : br2);
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} else {
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std::printf("> unknown branch type...\n");
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}
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} else if (cc_blk->m_vinstrs.back().mnemonic ==
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vm::instrs::mnemonic_t::vmexit) {
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cc_blk->branch_type = vm::instrs::vbranch_type::none;
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} else if (cc_blk->m_vinstrs.back().mnemonic == vm::instrs::mnemonic_t::jmp) {
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// see if there is 1 lconst...
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if (auto last_lconst = std::find_if(
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cc_blk->m_vinstrs.rbegin(), cc_blk->m_vinstrs.rend(),
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[&](vm::instrs::vinstr_t& vinstr) -> bool {
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return vinstr.mnemonic == vm::instrs::mnemonic_t::lconst &&
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vinstr.imm.size == 64;
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});
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last_lconst != cc_blk->m_vinstrs.rend()) {
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const auto imm_img_based = last_lconst->imm.val;
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const auto imm_mod_based =
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(imm_img_based - m_vm->m_image_base) + m_vm->m_module_base;
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// check to see if the imm is inside of the module... and if the ptr lands
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// inside of an executable section... then lastly check to see if its a
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// legit branch or not...
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if (imm_img_based >= m_vm->m_image_base &&
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imm_img_based < m_vm->m_image_base + m_vm->m_image_size &&
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vm::utils::scn::executable(m_vm->m_module_base, imm_mod_based)) {
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cc_blk->branches.push_back(imm_mod_based);
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cc_blk->branch_type = vm::instrs::vbranch_type::absolute;
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}
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} else {
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std::printf("> jump table detected... review instruction stream...\n");
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uc_emu_stop(uc);
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}
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}
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}
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void emu_t::int_callback(uc_engine* uc, std::uint32_t intno, emu_t* obj) {
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uc_err err;
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std::uintptr_t rip = 0ull;
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static thread_local zydis_decoded_instr_t instr;
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if ((err = uc_reg_read(uc, UC_X86_REG_RIP, &rip))) {
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std::printf("> failed to read rip... reason = %d\n", err);
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return;
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}
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if (!ZYAN_SUCCESS(ZydisDecoderDecodeBuffer(vm::utils::g_decoder.get(),
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reinterpret_cast<void*>(rip),
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PAGE_4KB, &instr))) {
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std::printf("> failed to decode instruction at = 0x%p\n", rip);
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if ((err = uc_emu_stop(uc))) {
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std::printf("> failed to stop emulation, exiting... reason = %d\n", err);
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exit(0);
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}
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return;
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}
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// advance rip over the instruction that caused the exception... this is
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// usually a division by 0...
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rip += instr.length;
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if ((err = uc_reg_write(uc, UC_X86_REG_RIP, &rip))) {
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std::printf("> failed to write rip... reason = %d\n", err);
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return;
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}
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}
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bool emu_t::branch_pred_spec_exec(uc_engine* uc, uint64_t address,
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uint32_t size, emu_t* obj) {
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uc_err err;
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static thread_local zydis_decoded_instr_t instr;
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if (!ZYAN_SUCCESS(ZydisDecoderDecodeBuffer(vm::utils::g_decoder.get(),
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reinterpret_cast<void*>(address),
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PAGE_4KB, &instr))) {
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std::printf("> failed to decode instruction at = 0x%p\n", address);
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if ((err = uc_emu_stop(uc))) {
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std::printf("> failed to stop emulation, exiting... reason = %d\n", err);
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exit(0);
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}
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return false;
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}
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if (instr.mnemonic == ZYDIS_MNEMONIC_INVALID) return false;
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uc_context* ctx;
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uc_context_alloc(uc, &ctx);
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uc_context_save(uc, ctx);
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// if this is the first instruction of this handler then save the stack...
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if (!obj->cc_trace.m_instrs.size()) {
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obj->cc_trace.m_stack = new std::uint8_t[STACK_SIZE];
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uc_mem_read(uc, STACK_BASE, obj->cc_trace.m_stack, STACK_SIZE);
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}
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obj->cc_trace.m_instrs.push_back({instr, ctx});
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// RET or JMP REG means the end of a vm handler...
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if (instr.mnemonic == ZYDIS_MNEMONIC_RET ||
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(instr.mnemonic == ZYDIS_MNEMONIC_JMP &&
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instr.operands[0].type == ZYDIS_OPERAND_TYPE_REGISTER)) {
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// deobfuscate the instruction stream before profiling...
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// makes it easier for profiles to be correct...
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vm::instrs::deobfuscate(obj->cc_trace);
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// find the last MOV REG, DWORD PTR [VIP] in the instruction stream, then
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// remove any instructions from this instruction to the JMP/RET...
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const auto rva_fetch = std::find_if(
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obj->cc_trace.m_instrs.rbegin(), obj->cc_trace.m_instrs.rend(),
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[& vip = obj->cc_trace.m_vip](
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const vm::instrs::emu_instr_t& instr) -> bool {
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const auto& i = instr.m_instr;
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return i.mnemonic == ZYDIS_MNEMONIC_MOV &&
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i.operands[0].type == ZYDIS_OPERAND_TYPE_REGISTER &&
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i.operands[1].type == ZYDIS_OPERAND_TYPE_MEMORY &&
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i.operands[1].mem.base == vip && i.operands[1].size == 32;
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});
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if (rva_fetch != obj->cc_trace.m_instrs.rend())
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obj->cc_trace.m_instrs.erase((rva_fetch + 1).base(),
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obj->cc_trace.m_instrs.end());
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const auto vinstr = vm::instrs::determine(obj->cc_trace);
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// -- free the trace since we will start a new one...
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std::for_each(obj->cc_trace.m_instrs.begin(), obj->cc_trace.m_instrs.end(),
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[&](const vm::instrs::emu_instr_t& instr) {
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uc_context_free(instr.m_cpu);
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});
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delete[] obj->cc_trace.m_stack;
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obj->cc_trace.m_instrs.clear();
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if (vinstr.mnemonic != vm::instrs::mnemonic_t::jmp) {
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if (vinstr.mnemonic != vm::instrs::mnemonic_t::sreg) uc_emu_stop(uc);
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if (!vinstr.imm.has_imm) uc_emu_stop(uc);
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if (vinstr.imm.size != 8 || vinstr.imm.val > 8 * VIRTUAL_REGISTER_COUNT)
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uc_emu_stop(uc);
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// -- stop after 10 legit SREG's...
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if (++obj->m_sreg_cnt == 10) uc_emu_stop(uc);
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}
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}
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return true;
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}
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bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
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emu_t* obj) {
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uc_err err;
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static thread_local zydis_decoded_instr_t instr;
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if (!ZYAN_SUCCESS(ZydisDecoderDecodeBuffer(vm::utils::g_decoder.get(),
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reinterpret_cast<void*>(address),
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PAGE_4KB, &instr))) {
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std::printf("> failed to decode instruction at = 0x%p\n", address);
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if ((err = uc_emu_stop(uc))) {
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std::printf("> failed to stop emulation, exiting... reason = %d\n", err);
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exit(0);
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}
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return false;
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}
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if (instr.mnemonic == ZYDIS_MNEMONIC_INVALID) return false;
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uc_context* ctx;
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uc_context_alloc(uc, &ctx);
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uc_context_save(uc, ctx);
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// if this is the first instruction of this handler then save the stack...
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if (!obj->cc_trace.m_instrs.size()) {
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obj->cc_trace.m_stack = new std::uint8_t[STACK_SIZE];
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obj->cc_trace.m_begin = address;
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uc_mem_read(uc, STACK_BASE, obj->cc_trace.m_stack, STACK_SIZE);
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}
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obj->cc_trace.m_instrs.push_back({instr, ctx});
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// RET or JMP REG means the end of a vm handler...
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if (instr.mnemonic == ZYDIS_MNEMONIC_RET ||
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(instr.mnemonic == ZYDIS_MNEMONIC_JMP &&
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instr.operands[0].type == ZYDIS_OPERAND_TYPE_REGISTER)) {
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// deobfuscate the instruction stream before profiling...
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// makes it easier for profiles to be correct...
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vm::instrs::deobfuscate(obj->cc_trace);
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// find the last MOV REG, DWORD PTR [VIP] in the instruction stream, then
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// remove any instructions from this instruction to the JMP/RET...
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const auto rva_fetch = std::find_if(
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obj->cc_trace.m_instrs.rbegin(), obj->cc_trace.m_instrs.rend(),
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[& vip = obj->cc_trace.m_vip](
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const vm::instrs::emu_instr_t& instr) -> bool {
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const auto& i = instr.m_instr;
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return i.mnemonic == ZYDIS_MNEMONIC_MOV &&
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i.operands[0].type == ZYDIS_OPERAND_TYPE_REGISTER &&
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i.operands[1].type == ZYDIS_OPERAND_TYPE_MEMORY &&
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i.operands[1].mem.base == vip && i.operands[1].size == 32;
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});
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if (rva_fetch != obj->cc_trace.m_instrs.rend())
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obj->cc_trace.m_instrs.erase((rva_fetch + 1).base(),
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obj->cc_trace.m_instrs.end());
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// set the virtual code block vip address information...
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if (!obj->cc_blk->m_vip.rva || !obj->cc_blk->m_vip.img_base) {
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// find the last write done to VIP...
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auto vip_write = std::find_if(
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obj->cc_trace.m_instrs.rbegin(), obj->cc_trace.m_instrs.rend(),
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[& vip =
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obj->cc_trace.m_vip](vm::instrs::emu_instr_t& instr) -> bool {
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const auto& i = instr.m_instr;
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return i.operands[0].type == ZYDIS_OPERAND_TYPE_REGISTER &&
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i.operands[0].reg.value == vip;
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});
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uc_context* backup;
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uc_context_alloc(uc, &backup);
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uc_context_save(uc, backup);
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uc_context_restore(uc, (--vip_write)->m_cpu);
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std::uintptr_t vip_addr = 0ull;
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uc_reg_read(uc, vm::instrs::reg_map[obj->cc_trace.m_vip], &vip_addr);
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obj->cc_blk->m_vip.rva = vip_addr -= obj->m_vm->m_module_base;
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obj->cc_blk->m_vip.img_base = vip_addr += obj->m_vm->m_image_base;
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uc_context_restore(uc, backup);
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uc_context_free(backup);
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} else {
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const auto vinstr = vm::instrs::determine(obj->cc_trace);
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if (vinstr.mnemonic != vm::instrs::mnemonic_t::unknown) {
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if (vinstr.imm.has_imm)
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std::printf("> %s %p\n",
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vm::instrs::get_profile(vinstr.mnemonic)->name.c_str(),
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vinstr.imm.val);
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else
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std::printf("> %s\n",
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vm::instrs::get_profile(vinstr.mnemonic)->name.c_str());
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} else {
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zydis_rtn_t inst_stream;
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std::for_each(obj->cc_trace.m_instrs.begin(),
|
|
obj->cc_trace.m_instrs.end(),
|
|
[&](vm::instrs::emu_instr_t& instr) {
|
|
inst_stream.push_back({instr.m_instr});
|
|
});
|
|
|
|
std::printf(
|
|
"> err: please define the following vm handler (at = %p):\n",
|
|
(obj->cc_trace.m_begin - obj->m_vm->m_module_base) +
|
|
obj->m_vm->m_image_base);
|
|
|
|
vm::utils::print(inst_stream);
|
|
uc_emu_stop(uc);
|
|
return false;
|
|
}
|
|
|
|
if (obj->cc_blk->m_vinstrs.size()) {
|
|
if (vinstr.mnemonic == vm::instrs::mnemonic_t::jmp) {
|
|
uc_context *backup, *copy;
|
|
|
|
// backup current unicorn-engine context...
|
|
uc_context_alloc(uc, &backup);
|
|
uc_context_alloc(uc, ©);
|
|
uc_context_save(uc, backup);
|
|
|
|
// make a copy of the first cpu context of the jmp handler...
|
|
uc_context_restore(uc, obj->cc_trace.m_instrs.begin()->m_cpu);
|
|
uc_context_save(uc, copy);
|
|
|
|
// restore the unicorn-engine context... also free the backup...
|
|
uc_context_restore(uc, backup);
|
|
uc_context_free(backup);
|
|
|
|
// set current code block virtual jmp instruction information...
|
|
obj->cc_blk->m_jmp.ctx = copy;
|
|
obj->cc_blk->m_jmp.rip = obj->cc_trace.m_begin;
|
|
obj->cc_blk->m_jmp.stack = new std::uint8_t[STACK_SIZE];
|
|
obj->cc_blk->m_jmp.m_vm = {obj->cc_trace.m_vip, obj->cc_trace.m_vsp};
|
|
std::memcpy(obj->cc_blk->m_jmp.stack, obj->cc_trace.m_stack,
|
|
STACK_SIZE);
|
|
}
|
|
|
|
if (vinstr.mnemonic == vm::instrs::mnemonic_t::jmp ||
|
|
vinstr.mnemonic == vm::instrs::mnemonic_t::vmexit)
|
|
uc_emu_stop(obj->uc);
|
|
}
|
|
|
|
obj->cc_blk->m_vinstrs.push_back(vinstr);
|
|
}
|
|
|
|
// -- free the trace since we will start a new one...
|
|
std::for_each(obj->cc_trace.m_instrs.begin(), obj->cc_trace.m_instrs.end(),
|
|
[&](const vm::instrs::emu_instr_t& instr) {
|
|
uc_context_free(instr.m_cpu);
|
|
});
|
|
|
|
delete[] obj->cc_trace.m_stack;
|
|
obj->cc_trace.m_instrs.clear();
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void emu_t::invalid_mem(uc_engine* uc, uc_mem_type type, uint64_t address,
|
|
int size, int64_t value, emu_t* obj) {
|
|
switch (type) {
|
|
case UC_MEM_READ_UNMAPPED: {
|
|
uc_mem_map(uc, address & ~0xFFFull, PAGE_4KB, UC_PROT_ALL);
|
|
std::printf(">>> reading invalid memory at address = %p, size = 0x%x\n",
|
|
address, size);
|
|
break;
|
|
}
|
|
case UC_MEM_WRITE_UNMAPPED: {
|
|
uc_mem_map(uc, address & ~0xFFFull, PAGE_4KB, UC_PROT_ALL);
|
|
std::printf(
|
|
">>> writing invalid memory at address = %p, size = 0x%x, val = "
|
|
"0x%x\n",
|
|
address, size, value);
|
|
break;
|
|
}
|
|
case UC_MEM_FETCH_UNMAPPED: {
|
|
std::printf(">>> fetching invalid instructions at address = %p\n",
|
|
address);
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
bool emu_t::legit_branch(vm::instrs::vblk_t& vblk, std::uintptr_t branch_addr) {
|
|
// remove normal execution callback...
|
|
uc_hook_del(uc, code_exec_hook);
|
|
|
|
// add branch pred hook...
|
|
uc_hook_add(uc, &branch_pred_hook, UC_HOOK_CODE,
|
|
(void*)&vm::emu_t::branch_pred_spec_exec, this,
|
|
m_vm->m_module_base, m_vm->m_module_base + m_vm->m_image_size);
|
|
|
|
// make a backup of the current emulation state...
|
|
uc_context* backup;
|
|
uc_context_alloc(uc, &backup);
|
|
uc_context_save(uc, backup);
|
|
std::uint8_t* stack = new std::uint8_t[STACK_SIZE];
|
|
uc_mem_read(uc, STACK_BASE, stack, STACK_SIZE);
|
|
|
|
// restore cpu and stack back to the virtual jump handler...
|
|
uc_context_restore(uc, vblk.m_jmp.ctx);
|
|
uc_mem_write(uc, STACK_BASE, vblk.m_jmp.stack, STACK_SIZE);
|
|
|
|
// force the virtual machine to try and emulate the branch address...
|
|
std::uintptr_t vsp = 0ull, rip = 0ull;
|
|
uc_reg_read(uc, UC_X86_REG_RIP, &rip);
|
|
uc_reg_read(uc, vm::instrs::reg_map[vblk.m_vm.vsp], &vsp);
|
|
uc_mem_write(uc, vsp, &branch_addr, sizeof branch_addr);
|
|
|
|
m_sreg_cnt = 0u;
|
|
uc_emu_start(uc, rip, 0ull, 0ull, 0ull);
|
|
|
|
// restore original cpu and stack...
|
|
uc_mem_write(uc, STACK_BASE, stack, STACK_SIZE);
|
|
uc_context_restore(uc, backup);
|
|
uc_context_free(backup);
|
|
delete[] stack;
|
|
|
|
// add normal execution callback back...
|
|
uc_hook_del(uc, branch_pred_hook);
|
|
uc_hook_add(uc, &code_exec_hook, UC_HOOK_CODE,
|
|
(void*)&vm::emu_t::code_exec_callback, this, m_vm->m_module_base,
|
|
m_vm->m_module_base + m_vm->m_image_size);
|
|
|
|
// we will consider this a legit branch if there is at least 10
|
|
// SREG instructions...
|
|
return m_sreg_cnt == 10;
|
|
}
|
|
|
|
std::optional<std::pair<std::uintptr_t, std::uintptr_t>> emu_t::could_have_jcc(
|
|
std::vector<vm::instrs::vinstr_t>& vinstrs) {
|
|
if (vinstrs.back().mnemonic == vm::instrs::mnemonic_t::vmexit) return {};
|
|
|
|
// check to see if there is at least 3 LCONST %i64's
|
|
if (std::accumulate(
|
|
vinstrs.begin(), vinstrs.end(), 0u,
|
|
[&](std::uint32_t val, vm::instrs::vinstr_t& v) -> std::uint32_t {
|
|
return v.mnemonic == vm::instrs::mnemonic_t::lconst &&
|
|
v.imm.size == 64
|
|
? ++val
|
|
: val;
|
|
}) < 3)
|
|
return {};
|
|
|
|
// extract the lconst64's out of the virtual instruction stream...
|
|
static const auto lconst64_chk = [&](vm::instrs::vinstr_t& v) -> bool {
|
|
return v.mnemonic == vm::instrs::mnemonic_t::lconst && v.imm.size == 64;
|
|
};
|
|
|
|
const auto lconst1 =
|
|
std::find_if(vinstrs.rbegin(), vinstrs.rend(), lconst64_chk);
|
|
|
|
if (lconst1 == vinstrs.rend()) return {};
|
|
|
|
const auto lconst2 = std::find_if(lconst1 + 1, vinstrs.rend(), lconst64_chk);
|
|
|
|
if (lconst2 == vinstrs.rend()) return {};
|
|
|
|
// check to see if the imm val is inside of the image...
|
|
if (lconst1->imm.val > m_vm->m_image_base + m_vm->m_image_size ||
|
|
lconst1->imm.val < m_vm->m_image_base ||
|
|
lconst2->imm.val > m_vm->m_image_base + m_vm->m_image_size ||
|
|
lconst2->imm.val < m_vm->m_image_base)
|
|
return {};
|
|
|
|
// check to see if the imm's points to something inside of an executable
|
|
// section...
|
|
if (!vm::utils::scn::executable(
|
|
m_vm->m_module_base,
|
|
(lconst1->imm.val - m_vm->m_image_base) + m_vm->m_module_base) ||
|
|
!vm::utils::scn::executable(
|
|
m_vm->m_module_base,
|
|
(lconst2->imm.val - m_vm->m_image_base) + m_vm->m_module_base))
|
|
return {};
|
|
|
|
return {{lconst1->imm.val, lconst2->imm.val}};
|
|
}
|
|
} // namespace vm
|