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Merged
EpicPlayerA10 merged 2 commits into from
Jan 28, 2026
Merged

Skidfuscator fixes #124

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0c60efa
Update ComposedSkidTransformer
Animowany Oct 27, 2025
cb6bde5
Fix endless-looping SkidFlowTransformer for older skidfuscator jars
Animowany Oct 27, 2025
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4 changes: 3 additions & 1 deletion ...rs/src/main/java/uwu/narumi/deobfuscator/core/other/composed/ComposedSkidTransformer.java
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Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@
import uwu.narumi.deobfuscator.core.other.impl.pool.InlineLocalVariablesTransformer;
import uwu.narumi.deobfuscator.core.other.impl.pool.InlineStaticFieldTransformer;
import uwu.narumi.deobfuscator.core.other.impl.skidfuscator.*;
import uwu.narumi.deobfuscator.core.other.impl.universal.StringBuilderTransformer;
import uwu.narumi.deobfuscator.core.other.impl.universal.UniversalFlowTransformer;
import uwu.narumi.deobfuscator.core.other.impl.universal.UniversalNumberTransformer;

Expand Down Expand Up @@ -38,7 +39,8 @@ public ComposedSkidTransformer() {
)
),
SkidStringTransformer::new,
SkidCleanTransformer::new
SkidCleanTransformer::new,
StringBuilderTransformer::new /* Sometimes SkidFuscator replaces concat's with StringBuilder for "optimization" */
);
}
}
66 changes: 36 additions & 30 deletions ...c/main/java/uwu/narumi/deobfuscator/core/other/impl/skidfuscator/SkidFlowTransformer.java
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Original file line number Diff line number Diff line change
Expand Up @@ -60,9 +60,9 @@ protected void transform() throws Exception {
});

/** Example
* ldc 952006311
* invokestatic ikjlkypytwnvkuzi/erfobcthglyygbhq.jwmyqfvhltjhsidh (I)I
* */
* ldc 952006311
* invokestatic ikjlkypytwnvkuzi/erfobcthglyygbhq.jwmyqfvhltjhsidh (I)I
* */
staticDecryption.findAllMatches(methodContext).forEach(matchContext -> {
MethodInsnNode methodInsnNode = matchContext.captures().get("predicate-method").insn().asMethodInsn();
AbstractInsnNode salt = matchContext.captures().get("salt").insn();
Expand All @@ -76,10 +76,12 @@ protected void transform() throws Exception {
JumpMatch.of().capture("jump").findAllMatches(methodContext).forEach(matchContext -> {
JumpInsnNode jumpInsnNode = matchContext.captures().get("jump").insn().asJump();
if (jumpInsnNode.label.getNext() instanceof LdcInsnNode intLdc && jumpInsnNode.label.getNext(2) instanceof VarInsnNode varStore && jumpInsnNode.label.getNext(3) instanceof JumpInsnNode jump1) {
if (blessedJumpLabels.contains(jump1.label)) return;
methodNode.instructions.remove(varStore);
methodNode.instructions.remove(intLdc);
methodNode.instructions.insert(jump1.label, varStore);
methodNode.instructions.insert(jump1.label, intLdc);
blessedJumpLabels.add(jump1.label);
markChange();
}
LdcInsnNode lastLdcOfLabel = null;
Expand All @@ -95,45 +97,49 @@ protected void transform() throws Exception {
setVarJump.findAllMatches(methodContext).forEach(matchContext1 -> {
if (finalLastLdcOfLabel.cst instanceof Integer && matchContext1.captures().get("salt1").insn().asInteger() == (int) finalLastLdcOfLabel.cst) {
VarInsnNode var = (VarInsnNode) matchContext1.captures().get("var").insn();
LabelNode blessedLabel = matchContext1.captures().get("jump").insn().asJump().label;
if (blessedJumpLabels.contains(blessedLabel)) return;
methodNode.instructions.insert(matchContext1.captures().get("jump").insn().asJump().label, new VarInsnNode(ISTORE, var.var));
methodNode.instructions.insert(matchContext1.captures().get("jump").insn().asJump().label, new LdcInsnNode(finalLastLdcOfLabel.cst));
blessedJumpLabels.add(blessedLabel);
}
});
}
});

if (!isChanged()) {
MatchContext matchContext = SequenceMatch.of(NumberMatch.numInteger().capture("hash"), OpcodeMatch.of(ISTORE).capture("param"), Match.of(ctx -> ctx.insn() instanceof LabelNode).capture("label")).doNotSkipLabels().findFirstMatch(methodContext);
if (matchContext != null) {
int salt = matchContext.captures().get("hash").insn().asInteger();
int param = ((VarInsnNode)matchContext.captures().get("param").insn()).var;
LabelNode label = (LabelNode) matchContext.captures().get("label").insn();
if (label.getNext() instanceof JumpInsnNode jumpInsnNode) label = jumpInsnNode.label;
if (blessedLabels.contains(label)) return;
LabelNode finalLabel = label;
methodNode.tryCatchBlocks.forEach(tcb -> {
if (finalLabel.equals(tcb.start) || finalLabel.equals(tcb.handler) || finalLabel.equals(tcb.end)) {
methodNode.instructions.insert(tcb.start, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(tcb.start, new LdcInsnNode(salt));
methodNode.instructions.insert(tcb.handler, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(tcb.handler, new LdcInsnNode(salt));
methodNode.instructions.insert(tcb.end, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(tcb.end, new LdcInsnNode(salt));
blessedLabels.add(tcb.start);
blessedLabels.add(tcb.handler);
blessedLabels.add(tcb.end);
}
});
methodNode.instructions.insert(label, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(label, new LdcInsnNode(salt));
markChange();
blessedLabels.add(label);
}
MatchContext matchContext = SequenceMatch.of(NumberMatch.numInteger().capture("hash"), OpcodeMatch.of(ISTORE).capture("param"), Match.of(ctx -> ctx.insn() instanceof LabelNode).capture("label")).doNotSkipLabels().findFirstMatch(methodContext);
if (matchContext != null) {
int salt = matchContext.captures().get("hash").insn().asInteger();
int param = ((VarInsnNode)matchContext.captures().get("param").insn()).var;
LabelNode label = (LabelNode) matchContext.captures().get("label").insn();
if (label.getNext() instanceof JumpInsnNode jumpInsnNode) label = jumpInsnNode.label;
if (blessedLabels.contains(label)) return;
LabelNode finalLabel = label;
methodNode.tryCatchBlocks.forEach(tcb -> {
if (finalLabel.equals(tcb.start) || finalLabel.equals(tcb.handler) || finalLabel.equals(tcb.end)) {
methodNode.instructions.insert(tcb.start, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(tcb.start, new LdcInsnNode(salt));
methodNode.instructions.insert(tcb.handler, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(tcb.handler, new LdcInsnNode(salt));
methodNode.instructions.insert(tcb.end, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(tcb.end, new LdcInsnNode(salt));
blessedLabels.add(tcb.start);
blessedLabels.add(tcb.handler);
blessedLabels.add(tcb.end);
}
});
methodNode.instructions.insert(label, new VarInsnNode(ISTORE, param));
methodNode.instructions.insert(label, new LdcInsnNode(salt));
markChange();
blessedLabels.add(label);
}
}
}));
}

private final static Set<LabelNode> blessedLabels = new HashSet<>();
private final static Set<LabelNode> blessedJumpLabels = new HashSet<>();

public int m1(int n) {
if (n != 0) {
Expand All @@ -145,4 +151,4 @@ public int m1(int n) {
public int m2_m3(int n) {
return (n & 0xE0000000) >> 29 | n << 3;
}
}
}