Fix for meso exploit with shops

[flav]

I usually don't share fixes with the public anymore, only with Lai, though he has fixed most of the exploits I find already. : Anyways, decided to release the fix for this one because the guys who did it on my server yesterday are fags and they don't deserve to be able to exploit, not even on Soul's servers. I assume this works on most servers because I haven't seen this fixed in any public sources.

MapleShop.java

if (c.getPlayer().getMeso() >= item.getPrice() * quantity) {

Change that to either

if (c.getPlayer().getMeso() >= (long) item.getPrice() * quantity) {

or (I suggest to use this method, otherwise you will also have to check for the quantity not being negative.)

int price = item.getPrice() * quantity;
if (price >= 0 && c.getPlayer().getMeso() >= price) {

to prevent overflow.

 

[ImReplay]

Nice released flav, :S

 

[AuroX]

nice release, btw, isn't it supposed to be

int price = item.getPrice() * quantity;
if (price >= 0 && c.getPlayer().getMeso() >[COLOR="Red"]=[/COLOR] price) {

If meso > price and not >=, players will not be able to buy any items although their meso is same price as items

 

[flav]

Of course, just a typo. Fixed.

 

[xReflex]

well done flav. Even though thats fixed by most unstupid coders .

 

[Xerixe]

^ So you're saying flav was stupid for not fixing it earlier?

 

[xReflex]

I bet he fixed it earlier. He just now released it boy

 

[nugyyman]

The reason for the rollback...
Anyways thanks for sharing it with us.

 

[maxcloud]

post removed.

 

[eternalms]

This made me giggle. Careful what you say, The almighty eye is watching.

OT: Thanks Flav, Nice Release.

---------- Post added at 06:15 PM ---------- Previous post was at 06:14 PM ----------



lolwut?

almighty eye...., you mean your whispering-eye :X

OT : nice XD

 

[King Grub]

well done flav. Even though thats fixed by most unstupid coders .

You can't fix something you don't know "exist".

 

[Shawn]

Let's not turn this into some pathetic argument over who is better at what... Stick to the topic.

 

[SeanDev]

if (item != null && item.getPrice() > 0) {
            if (c.getPlayer().getMeso() >= item.getPrice() * quantity) {

Wouldn't this also work? Found it in my source.

 

[flav]

if (item != null && item.getPrice() > 0) {
            if (c.getPlayer().getMeso() >= item.getPrice() * quantity) {

Wouldn't this also work? Found it in my source.

The problem is that if you buy so many of the item that the the price goes higher than Integer.MAX_VALUE (2,147,483,647) it goes negative again, then the player surely has more mesos than the price is. Then he gets the items and doesn't lose but gains the money he should pay.

 

[SeanDev]

The problem is that if you buy so many of the item that the the price goes higher than Integer.MAX_VALUE (2,147,483,647) it goes negative again, then the player surely has more mesos than the price is. Then he gets the items and doesn't lose but gains the money he should pay.

Correct me if I'm wrong, but doesn't the price > 0 thing fix that?

Wait I feel stupid.

 

[XxОsirisxX]

Indeed, price > 0 should fix it. But yeah, flav also posted that in the very first post.

 

[made4forum]

int price = item.getPrice() * quantity;
if (price >= 0 && c.getPlayer().getMeso() >= price) {

Is it possible for a player to buy so many of an expensive item the price overflows to positive again?

 

[flav]

I never tried but Lai says it's not. I prefer the converting to long method, though it wastes 4 bytes.

Correct me if I'm wrong, but doesn't the price > 0 thing fix that?

Wait I feel stupid.

But you have to multiply the price with the quantity before you check for the price being >= 0.

 

[mertjuh]

just wondering why are you using long and not just stick to an int?

 

[CioNide]

just wondering why are you using long and not just stick to an int?

Look up what a Long is, then an Integer.