Examples with BlockNode jadx.core.dex.nodes.BlockNode used on opensource projects

Example 1 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class ProcessTryCatchRegions method checkAndWrap.

private static boolean checkAndWrap(MethodNode mth, Map<BlockNode, TryCatchBlock> tryBlocksMap, IRegion region) {
    // search dominator blocks in this region (don't need to go deeper)
    for (Map.Entry<BlockNode, TryCatchBlock> entry : tryBlocksMap.entrySet()) {
        BlockNode dominator = entry.getKey();
        if (region.getSubBlocks().contains(dominator)) {
            TryCatchBlock tb = tryBlocksMap.get(dominator);
            if (!wrapBlocks(region, tb, dominator)) {
                ErrorsCounter.methodError(mth, "Can't wrap try/catch for " + region);
            }
            tryBlocksMap.remove(dominator);
            return true;
        }
    }
    return false;
}

Example 2 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class ProcessTryCatchRegions method searchTryCatchDominators.

private static void searchTryCatchDominators(MethodNode mth, Map<BlockNode, TryCatchBlock> tryBlocksMap) {
    Set<TryCatchBlock> tryBlocks = new HashSet<TryCatchBlock>();
    // collect all try/catch blocks
    for (BlockNode block : mth.getBasicBlocks()) {
        CatchAttr c = block.get(AType.CATCH_BLOCK);
        if (c != null) {
            tryBlocks.add(c.getTryBlock());
        }
    }
    // for each try block search nearest dominator block
    for (TryCatchBlock tb : tryBlocks) {
        if (tb.getHandlersCount() == 0) {
            LOG.warn("No exception handlers in catch block, method: {}", mth);
            continue;
        }
        BitSet bs = new BitSet(mth.getBasicBlocks().size());
        for (ExceptionHandler excHandler : tb.getHandlers()) {
            SplitterBlockAttr splitter = excHandler.getHandlerBlock().get(AType.SPLITTER_BLOCK);
            if (splitter != null) {
                BlockNode block = splitter.getBlock();
                bs.set(block.getId());
            }
        }
        List<BlockNode> domBlocks = BlockUtils.bitSetToBlocks(mth, bs);
        BlockNode domBlock;
        if (domBlocks.size() != 1) {
            domBlock = BlockUtils.getTopBlock(domBlocks);
            if (domBlock == null) {
                throw new JadxRuntimeException("Exception block dominator not found, method:" + mth + ". bs: " + domBlocks);
            }
        } else {
            domBlock = domBlocks.get(0);
        }
        TryCatchBlock prevTB = tryBlocksMap.put(domBlock, tb);
        if (prevTB != null) {
            ErrorsCounter.methodError(mth, "Failed to process nested try/catch");
        }
    }
}

Example 3 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class RegionMaker method processExcHandler.

private void processExcHandler(ExceptionHandler handler, Set<BlockNode> exits) {
    BlockNode start = handler.getHandlerBlock();
    if (start == null) {
        return;
    }
    RegionStack stack = new RegionStack(mth);
    BlockNode dom;
    if (handler.isFinally()) {
        SplitterBlockAttr splitterAttr = start.get(AType.SPLITTER_BLOCK);
        if (splitterAttr == null) {
            return;
        }
        dom = splitterAttr.getBlock();
    } else {
        dom = start;
        stack.addExits(exits);
    }
    BitSet domFrontier = dom.getDomFrontier();
    List<BlockNode> handlerExits = BlockUtils.bitSetToBlocks(mth, domFrontier);
    boolean inLoop = mth.getLoopForBlock(start) != null;
    for (BlockNode exit : handlerExits) {
        if ((!inLoop || BlockUtils.isPathExists(start, exit)) && RegionUtils.isRegionContainsBlock(mth.getRegion(), exit)) {
            stack.addExit(exit);
        }
    }
    handler.setHandlerRegion(makeRegion(start, stack));
    ExcHandlerAttr excHandlerAttr = start.get(AType.EXC_HANDLER);
    if (excHandlerAttr == null) {
        LOG.warn("Missing exception handler attribute for start block");
    } else {
        handler.getHandlerRegion().addAttr(excHandlerAttr);
    }
}

Example 4 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class RegionMaker method processSwitch.

private BlockNode processSwitch(IRegion currentRegion, BlockNode block, SwitchNode insn, RegionStack stack) {
    SwitchRegion sw = new SwitchRegion(currentRegion, block);
    currentRegion.getSubBlocks().add(sw);
    int len = insn.getTargets().length;
    // sort by target
    Map<Integer, List<Object>> casesMap = new LinkedHashMap<Integer, List<Object>>(len);
    for (int i = 0; i < len; i++) {
        Object key = insn.getKeys()[i];
        int targ = insn.getTargets()[i];
        List<Object> keys = casesMap.get(targ);
        if (keys == null) {
            keys = new ArrayList<Object>(2);
            casesMap.put(targ, keys);
        }
        keys.add(key);
    }
    Map<BlockNode, List<Object>> blocksMap = new LinkedHashMap<BlockNode, List<Object>>(len);
    for (Map.Entry<Integer, List<Object>> entry : casesMap.entrySet()) {
        BlockNode c = getBlockByOffset(entry.getKey(), block.getSuccessors());
        if (c == null) {
            throw new JadxRuntimeException("Switch block not found by offset: " + entry.getKey());
        }
        blocksMap.put(c, entry.getValue());
    }
    BlockNode defCase = getBlockByOffset(insn.getDefaultCaseOffset(), block.getSuccessors());
    if (defCase != null) {
        blocksMap.remove(defCase);
    }
    LoopInfo loop = mth.getLoopForBlock(block);
    Map<BlockNode, BlockNode> fallThroughCases = new LinkedHashMap<BlockNode, BlockNode>();
    List<BlockNode> basicBlocks = mth.getBasicBlocks();
    BitSet outs = new BitSet(basicBlocks.size());
    outs.or(block.getDomFrontier());
    for (BlockNode s : block.getCleanSuccessors()) {
        BitSet df = s.getDomFrontier();
        // fall through case block
        if (df.cardinality() > 1) {
            if (df.cardinality() > 2) {
                LOG.debug("Unexpected case pattern, block: {}, mth: {}", s, mth);
            } else {
                BlockNode first = basicBlocks.get(df.nextSetBit(0));
                BlockNode second = basicBlocks.get(df.nextSetBit(first.getId() + 1));
                if (second.getDomFrontier().get(first.getId())) {
                    fallThroughCases.put(s, second);
                    df = new BitSet(df.size());
                    df.set(first.getId());
                } else if (first.getDomFrontier().get(second.getId())) {
                    fallThroughCases.put(s, first);
                    df = new BitSet(df.size());
                    df.set(second.getId());
                }
            }
        }
        outs.or(df);
    }
    outs.clear(block.getId());
    if (loop != null) {
        outs.clear(loop.getStart().getId());
    }
    stack.push(sw);
    stack.addExits(BlockUtils.bitSetToBlocks(mth, outs));
    // check cases order if fall through case exists
    if (!fallThroughCases.isEmpty()) {
        if (isBadCasesOrder(blocksMap, fallThroughCases)) {
            LOG.debug("Fixing incorrect switch cases order, method: {}", mth);
            blocksMap = reOrderSwitchCases(blocksMap, fallThroughCases);
            if (isBadCasesOrder(blocksMap, fallThroughCases)) {
                LOG.error("Can't fix incorrect switch cases order, method: {}", mth);
                mth.add(AFlag.INCONSISTENT_CODE);
            }
        }
    }
    // filter 'out' block
    if (outs.cardinality() > 1) {
        // remove exception handlers
        BlockUtils.cleanBitSet(mth, outs);
    }
    if (outs.cardinality() > 1) {
        // filter loop start and successors of other blocks
        for (int i = outs.nextSetBit(0); i >= 0; i = outs.nextSetBit(i + 1)) {
            BlockNode b = basicBlocks.get(i);
            outs.andNot(b.getDomFrontier());
            if (b.contains(AFlag.LOOP_START)) {
                outs.clear(b.getId());
            } else {
                for (BlockNode s : b.getCleanSuccessors()) {
                    outs.clear(s.getId());
                }
            }
        }
    }
    if (loop != null && outs.cardinality() > 1) {
        outs.clear(loop.getEnd().getId());
    }
    if (outs.cardinality() == 0) {
        // run expensive algorithm for find 'out' block
        for (BlockNode maybeOut : block.getSuccessors()) {
            boolean allReached = true;
            for (BlockNode s : block.getSuccessors()) {
                if (!isPathExists(s, maybeOut)) {
                    allReached = false;
                    break;
                }
            }
            if (allReached) {
                outs.set(maybeOut.getId());
                break;
            }
        }
    }
    BlockNode out = null;
    if (outs.cardinality() == 1) {
        out = basicBlocks.get(outs.nextSetBit(0));
        stack.addExit(out);
    } else if (loop == null && outs.cardinality() > 1) {
        LOG.warn("Can't detect out node for switch block: {} in {}", block, mth);
    }
    if (loop != null) {
        // check if 'continue' must be inserted
        BlockNode end = loop.getEnd();
        if (out != end && out != null) {
            insertContinueInSwitch(block, out, end);
        }
    }
    if (!stack.containsExit(defCase)) {
        sw.setDefaultCase(makeRegion(defCase, stack));
    }
    for (Entry<BlockNode, List<Object>> entry : blocksMap.entrySet()) {
        BlockNode caseBlock = entry.getKey();
        if (stack.containsExit(caseBlock)) {
            // empty case block
            sw.addCase(entry.getValue(), new Region(stack.peekRegion()));
        } else {
            BlockNode next = fallThroughCases.get(caseBlock);
            stack.addExit(next);
            Region caseRegion = makeRegion(caseBlock, stack);
            stack.removeExit(next);
            if (next != null) {
                next.add(AFlag.FALL_THROUGH);
                caseRegion.add(AFlag.FALL_THROUGH);
            }
            sw.addCase(entry.getValue(), caseRegion);
        // 'break' instruction will be inserted in RegionMakerVisitor.PostRegionVisitor
        }
    }
    stack.pop();
    return out;
}

Example 5 with BlockNode

use of jadx.core.dex.nodes.BlockNode in project jadx by skylot.

the class ModVisitor method replaceStep.

private static void replaceStep(MethodNode mth, InstructionRemover remover) {
    ClassNode parentClass = mth.getParentClass();
    for (BlockNode block : mth.getBasicBlocks()) {
        remover.setBlock(block);
        int size = block.getInstructions().size();
        for (int i = 0; i < size; i++) {
            InsnNode insn = block.getInstructions().get(i);
            switch(insn.getType()) {
                case INVOKE:
                    processInvoke(mth, block, i, remover);
                    break;
                case CONST:
                case CONST_STR:
                case CONST_CLASS:
                    {
                        FieldNode f;
                        if (insn.getType() == InsnType.CONST_STR) {
                            String s = ((ConstStringNode) insn).getString();
                            f = parentClass.getConstField(s);
                        } else if (insn.getType() == InsnType.CONST_CLASS) {
                            ArgType t = ((ConstClassNode) insn).getClsType();
                            f = parentClass.getConstField(t);
                        } else {
                            f = parentClass.getConstFieldByLiteralArg((LiteralArg) insn.getArg(0));
                        }
                        if (f != null) {
                            InsnNode inode = new IndexInsnNode(InsnType.SGET, f.getFieldInfo(), 0);
                            inode.setResult(insn.getResult());
                            replaceInsn(block, i, inode);
                        }
                        break;
                    }
                case SWITCH:
                    SwitchNode sn = (SwitchNode) insn;
                    for (int k = 0; k < sn.getCasesCount(); k++) {
                        FieldNode f = parentClass.getConstField(sn.getKeys()[k]);
                        if (f != null) {
                            sn.getKeys()[k] = f;
                        }
                    }
                    break;
                case NEW_ARRAY:
                    // create array in 'fill-array' instruction
                    int next = i + 1;
                    if (next < size) {
                        InsnNode ni = block.getInstructions().get(next);
                        if (ni.getType() == InsnType.FILL_ARRAY) {
                            ni.getResult().merge(mth.dex(), insn.getResult());
                            ArgType arrType = ((NewArrayNode) insn).getArrayType();
                            ((FillArrayNode) ni).mergeElementType(mth.dex(), arrType.getArrayElement());
                            remover.add(insn);
                        }
                    }
                    break;
                case FILL_ARRAY:
                    InsnNode filledArr = makeFilledArrayInsn(mth, (FillArrayNode) insn);
                    replaceInsn(block, i, filledArr);
                    break;
                case MOVE_EXCEPTION:
                    processMoveException(mth, block, insn, remover);
                    break;
                case ARITH:
                    ArithNode arithNode = (ArithNode) insn;
                    if (arithNode.getArgsCount() == 2) {
                        InsnArg litArg = arithNode.getArg(1);
                        if (litArg.isLiteral()) {
                            FieldNode f = parentClass.getConstFieldByLiteralArg((LiteralArg) litArg);
                            if (f != null) {
                                InsnNode fGet = new IndexInsnNode(InsnType.SGET, f.getFieldInfo(), 0);
                                insn.replaceArg(litArg, InsnArg.wrapArg(fGet));
                            }
                        }
                    }
                    break;
                default:
                    break;
            }
        }
        remover.perform();
    }
}