Jump to content
  • 0

Packet decrypt


Question

Posted

I'm trying to make a tool which includes packet decryptation, however I'm stuck on decrypt results. My application gets KeyPacket and find the BF Key, then I use it with this formula:

 

public byte[] decryptRecv(byte[] raw, final int size)
{
	if (!_isEnabled)
		return null;

	int temp = 0;
	for (int i = 0; i < size; i++)
	{
		int temp2 = raw[i] & 0xFF;
		raw[i] = (byte) (temp2 ^ _inKey[i&15] ^ temp);
		temp = temp2;
	}

	int old = _inKey[8] &0xff;
	old |= _inKey[9] << 8 &0xff00;
	old |= _inKey[10] << 0x10 &0xff0000;
	old |= _inKey[11] << 0x18 &0xff000000;

	old += size;

	_inKey[8] = (byte)(old &0xff);
	_inKey[9] = (byte)(old >> 0x08 &0xff);
	_inKey[10] = (byte)(old >> 0x10 &0xff);
	_inKey[11] = (byte)(old >> 0x18 &0xff);

	return raw;
}

 

This is the formula used by the emulators (gameserver part) but with the return of modified raw instead of void.

 

I checked if the hex key is fine, and it is.

Dunno if the conversion to byte is wrong, I'm using this:

 

public byte[] hexToBytes(String hex)
{
	hex = hex.replaceAll(" ", "");
	byte[] b = new BigInteger(hex, 16).toByteArray();

	return b;
}

 

I'm comparing the decryptation results with PHX results. Once every 15 checks, it goes ok, but the others, some bytes are different from PHX.

For example:

 

RequestAuthLogin of PHX

08 73 00 6D 00 61 00 6C 00 6C 00 76 00 69 00 6C 00 6C 00 65 00 00 00 FB 3F 00 00 87 69 00 00 00 00 00 00 00 00 00 00 01 00 00 00

 

Now, the same packet on my application:

00 08 73 00 6D 00 61 00 6C 00 6C 00 76 00 69 00 FB 00 6C 00 65 00 00 00 FB 3F 00 00 87 69 00 00 97 00 00 00 00 00 00 00 01 00 00 7E

 

Bold hex are different of PHX. Also, the differences are always at these bytes.

 

What am I doing wrong?

 

Thanks

0 answers to this question

Recommended Posts

There have been no answers to this question yet

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Posts

    • Looking a datapack developer for 'Essence' - needs to be good with Mobius structure,  Project is using old fork (I think base from crusader). Write Discord to PM.
    • We are not back on 2005, life in our days is harder than before, in complection with other things yes, L2 has not the same look.
    • ⚔️ L2 Nexus — Full-Stack Development for Lineage 2 Servers   One team for everything. Website, admin panel, launcher, server development, hosting, protection — built together, working together.   ━━━━━━━━━━━━━━━━━━━━━   SERVICES:   🌐 Server Website Registration, player cabinet, donate shop, statistics, voting, news. Integrated with your server — live data from game DB.   🛡️ Admin Panel (CMS) — 60 Modules Web panel for GM team: bans, kicks, item management, payments, analytics. Battle Pass, marketplace, anti-bot, churn prediction, Discord/Telegram bots.   🚀 Custom Launcher Electron launcher with delta patcher, CDN delivery, news feed, integrity check, multi-server support. Fully branded.   ⚔️ Java Development Custom modules for L2J / aCis / Lucera / L2Off (PTS). Events, NPCs, instances, balance, quests, skills — any complexity.   🛡️ Hosting & DDoS Protection Server setup, OVH Game DDoS, Cloudflare, monitoring 24/7.   ━━━━━━━━━━━━━━━━━━━━━   PRICING (Website + CMS):   Core — €1,000 (one-time) Website + player cabinet + tickets + live status. 30 days support.   Business — €2,500 (one-time) ⭐ + Donate shop, payment systems, admin panel, RBAC, analytics, bots. Custom design. 90 days priority support.   Enterprise — €5,000+ (custom) + Battle Pass, marketplace, anti-bot, churn, economy, backups, Wiki, API. Managed hosting, SLA 99.9%. 12 months support.   ━━━━━━━━━━━━━━━━━━━━━   JAVA DEVELOPMENT:   • PvP Events .............. from €200 • Custom NPCs ............. from €80 • Donate & Economy ........ from €150 • Instance Zones .......... from €300 • Balance & Skills ........ from €100 • Quests .................. from €250 • Olympiad & Sieges ....... from €200 • PTS Extenders ........... from €150 • Bug Fixes ............... from €50/hr • Custom Systems .......... from €500   ━━━━━━━━━━━━━━━━━━━━━   Platforms: L2J · aCis · Lucera · L2Off/PTS Chronicles: Interlude · High Five · Classic · Essence 📍 Live CMS demo available — message us on Telegram   Telegram: @l2nexus Website: https://l2-nexus.com
  • Topics

×
×
  • Create New...

Important Information

This community uses essential cookies to function properly. Non-essential cookies and third-party services are used only with your consent. Read our Privacy Policy and We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue..