Add support for LZNT1 decompression.

This commit is contained in:
Maxime THIEBAUT 2023-12-25 01:17:16 +01:00
parent 6ed9d4554a
commit 77042abc23
8 changed files with 161 additions and 2 deletions

1
.gitignore vendored
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@ -3,6 +3,7 @@ npm-debug.log
travis.log
build
.vscode
.idea
.*.swp
src/core/config/modules/*
src/core/config/OperationConfig.json

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@ -351,7 +351,8 @@
"LZMA Decompress",
"LZMA Compress",
"LZ4 Decompress",
"LZ4 Compress"
"LZ4 Compress",
"LZNT1 Decompress"
]
},
{

88
src/core/lib/LZNT1.mjs Normal file
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@ -0,0 +1,88 @@
/**
*
* LZNT1 Decompress.
*
* @author 0xThiebaut [thiebaut.dev]
* @copyright Crown Copyright 2023
* @license Apache-2.0
*
* https://github.com/Velocidex/go-ntfs/blob/master/parser%2Flznt1.go
*/
import Utils from "../Utils.mjs";
import OperationError from "../errors/OperationError.mjs";
const COMPRESSED_MASK = 1 << 15,
SIZE_MASK = (1 << 12) - 1;
/**
* @param {number} offset
* @returns {number}
*/
function getDisplacement(offset) {
let result = 0;
while (offset >= 0x10) {
offset >>= 1;
result += 1;
}
return result;
}
/**
* @param {byteArray} compressed
* @returns {byteArray}
*/
export function decompress(compressed) {
const decompressed = Array();
let coffset = 0;
while (coffset + 2 <= compressed.length) {
const doffset = decompressed.length;
const blockHeader = Utils.byteArrayToInt(compressed.slice(coffset, coffset + 2), "little");
coffset += 2;
const size = blockHeader & SIZE_MASK;
const blockEnd = coffset + size + 1;
if (size === 0) {
break;
} else if (compressed.length < coffset + size) {
throw new OperationError("Malformed LZNT1 stream: Block too small! Has the stream been truncated?");
}
if ((blockHeader & COMPRESSED_MASK) !== 0) {
while (coffset < blockEnd) {
let header = compressed[coffset++];
for (let i = 0; i < 8 && coffset < blockEnd; i++) {
if ((header & 1) === 0) {
decompressed.push(compressed[coffset++]);
} else {
const pointer = Utils.byteArrayToInt(compressed.slice(coffset, coffset + 2), "little");
coffset += 2;
const displacement = getDisplacement(decompressed.length - doffset - 1);
const symbolOffset = (pointer >> (12 - displacement)) + 1;
const symbolLength = (pointer & (0xFFF >> displacement)) + 2;
const shiftOffset = decompressed.length - symbolOffset;
for (let shiftDelta = 0; shiftDelta < symbolLength + 1; shiftDelta++) {
const shift = shiftOffset + shiftDelta;
if (shift < 0 || decompressed.length <= shift) {
throw new OperationError("Malformed LZNT1 stream: Invalid shift!");
}
decompressed.push(decompressed[shift]);
}
}
header >>= 1;
}
}
} else {
decompressed.push(...compressed.slice(coffset, coffset + size + 1));
coffset += size + 1;
}
}
return decompressed;
}

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@ -0,0 +1,41 @@
/**
* @author 0xThiebaut [thiebaut.dev]
* @copyright Crown Copyright 2023
* @license Apache-2.0
*/
import Operation from "../Operation.mjs";
import {decompress} from "../lib/LZNT1.mjs";
/**
* LZNT1 Decompress operation
*/
class LZNT1Decompress extends Operation {
/**
* LZNT1 Decompress constructor
*/
constructor() {
super();
this.name = "LZNT1 Decompress";
this.module = "Compression";
this.description = "Decompresses data using the LZNT1 algorithm.<br><br>Similar to the Windows API <code>RtlDecompressBuffer</code>.";
this.infoURL = "https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-xca/5655f4a3-6ba4-489b-959f-e1f407c52f15";
this.inputType = "byteArray";
this.outputType = "byteArray";
this.args = [];
}
/**
* @param {byteArray} input
* @param {Object[]} args
* @returns {byteArray}
*/
run(input, args) {
return decompress(input);
}
}
export default LZNT1Decompress;

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@ -62,7 +62,8 @@
"Training branch predictor...",
"Timing cache hits...",
"Speculatively executing recipes...",
"Adding LLM hallucinations..."
"Adding LLM hallucinations...",
"Decompressing malware..."
];
// Shuffle array using Durstenfeld algorithm

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@ -635,6 +635,10 @@ WWFkYSBZYWRh\r
assert.strictEqual(chef.keccak("Flea Market").toString(), "c2a06880b19e453ee5440e8bd4c2024bedc15a6630096aa3f609acfd2b8f15f27cd293e1cc73933e81432269129ce954a6138889ce87831179d55dcff1cc7587");
}),
it("LZNT1 Decompress", () => {
assert.strictEqual(chef.LZNT1Decompress("\x1a\xb0\x00compress\x00edtestda\x04ta\x07\x88alot").toString(), "compressedtestdatacompressedalot");
}),
it("MD6", () => {
assert.strictEqual(chef.MD6("Head Over Heels", {key: "arty"}).toString(), "d8f7fe4931fbaa37316f76283d5f615f50ddd54afdc794b61da522556aee99ad");
}),

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@ -62,6 +62,7 @@ import "./tests/JSONtoCSV.mjs";
import "./tests/JWTDecode.mjs";
import "./tests/JWTSign.mjs";
import "./tests/JWTVerify.mjs";
import "./tests/LZNT1Decompress.mjs";
import "./tests/MS.mjs";
import "./tests/Magic.mjs";
import "./tests/MorseCode.mjs";

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@ -0,0 +1,22 @@
/**
* LZNT1 Decompress tests.
*
* @author 0xThiebaut [thiebaut.dev]
* @copyright Crown Copyright 2023
* @license Apache-2.0
*/
import TestRegister from "../../lib/TestRegister.mjs";
TestRegister.addTests([
{
name: "LZNT1 Decompress",
input: "\x1a\xb0\x00compress\x00edtestda\x04ta\x07\x88alot",
expectedOutput: "compressedtestdatacompressedalot",
recipeConfig: [
{
op: "LZNT1 Decompress",
args: []
}
],
}
]);