mirrors/CyberChef
1
0
Fork 0
mirror of https://github.com/gchq/CyberChef.git synced 2025-05-08 07:21:02 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

Gzip decryption now supports 2 libraries and threshold search.

Browse source 
Gzip decryption now stop decrypting at the position of plaintext searched by threshold
This commit is contained in:
Windham Wong 2017-10-21 07:51:03 +01:00
parent 5b9665e8b9
commit fde87fd95c
3 changed files with 70 additions and 19 deletions
Download patch file Download diff file Expand all files Collapse all files

17
src/core/config/OperationConfig.js
View file

@ -1759,10 +1759,21 @@ const OperationConfig = {
},
"HTTP gzip Decrypt": {
module: "Compression",
description: "Decrypts Gzip payload from a request or response and returning plaintext of the header and decrypted payload.",
description: "Decrypts Gzip payload from a request or response and returning plaintext of the header and decrypted payload.<br><br>Arguments:<br>Library: The library used for decoding GZIP data.<br>Threshold: The threshold value for searching non-GZIP data. It has to be at least 8.",
inputType: "byteArray",
outputType: "byteArray",
args: []
args: [
{
name: "Library",
type: "option",
value: Compress.HTTP_GZIP_OPTION
},
{
name: "Threshold",
type: "number",
value: Compress.HTTP_GZIP_THRESHOLD
},
]
},
"Parse User Agent": {
module: "HTTP",
@ -3879,7 +3890,7 @@ const OperationConfig = {
},
"Strip TCP Headers": {
module: "Packets",
description: "Remove selected TCP headers from hexstream",
description: "Remove selected TCP headers from hexstream using Regular Expressions.<br /><br />Ethernet Header: <code>/^(([0-9a-f]{4} ){6,8}0800 )/igm</code><br />IP Header: <code>/^((45[0-9a-f]{2} ([0-9a-f]{4} ){9}))/igm</code><br />TCP Header: <code>/^([0-9a-f]{4} ){6}((80[0-9a-f]{2} ([0-9a-f]{4} ?){9})|(50[0-9a-f]{2} ([0-9a-f]{4} ?){3}))/igm</code>",
inputType: "string",
outputType: "string",
args: [

2
src/core/config/modules/Compression.js
View file

@ -26,7 +26,7 @@ OpModules.Compression = {
"Bzip2 Decompress": Compress.runBzip2Decompress,
"Tar": Compress.runTar,
"Untar": Compress.runUntar,
"HTTP gzip Decrypt":Compress.runHttpGzip,
"HTTP gzip Decrypt": Compress.runHttpGzip,
};

46
src/core/operations/Compress.js
View file

@ -255,6 +255,17 @@ const Compress = {
},
/**
* @constant
* @default
*/
HTTP_GZIP_OPTION: ["pako.js", "zlib.js"],
/**
* @constant
* @default
*/
HTTP_GZIP_THRESHOLD: 8,
/**
* HTTP Gzip operation.
*
@ -263,18 +274,47 @@ const Compress = {
* @returns {byteArray}
*/
runHttpGzip: function(input, args) {
const library = Compress.HTTP_GZIP_OPTION.indexOf(args[0]);
let threshold = Compress.HTTP_GZIP_THRESHOLD;
if (args[1] > 8) {
threshold = args[1];
}
input = Utils.byteArrayToHexNoSpace(input);
let output = input;
let regexStr = /1f8b080[0-8][0-9a-f]{12}/;
let gzipPos = input.search(regexStr);
if (gzipPos === -1) {
return Utils.hexToByteArray(input);
}
let plainData = input.substr(0, gzipPos);
let gzipData = input.substr(gzipPos);
while (gzipPos !== -1) {
output = input;
let plainData = output.substr(0, gzipPos);
let gzipData = output.substr(gzipPos);
let httpDataAfter = "";
let httpDataPosRegex = new RegExp("/((3[0-9])|(6[0-9a-f])|(7[0-9a])|(4[0-9a-f])|(5[0-9a])|(2[e-f])|(2b)|(20)){" + threshold + "}/");
let httpDataPos = gzipData.search(httpDataPosRegex);
if (httpDataPos !== -1) {
httpDataAfter = gzipData.substr(httpDataPos);
gzipData = gzipData.substr(0, httpDataPos);
}
console.log(httpDataPos);
gzipData = Utils.hexToByteArray(gzipData);
return Utils.hexToByteArray(plainData).concat(Array.prototype.slice.call(pako.ungzip(gzipData)));
if (library === 0) {
output = Utils.hexToByteArray(plainData).concat(Array.prototype.slice.call(pako.inflate(gzipData))).concat(Utils.hexToByteArray(httpDataAfter));
} else if (library === 1) {
let gzipDataRaw = new Zlib.Gunzip(gzipData);
output = Utils.hexToByteArray(plainData).concat(Array.prototype.slice.call(gzipDataRaw.decompress())).concat(Utils.hexToByteArray("0d0a 0d0a")).concat(Utils.hexToByteArray(httpDataAfter));
}
input = Utils.byteArrayToHexNoSpace(output);
gzipPos = input.search(regexStr);
}
return output;
},