Bitcoin Faucet changes

[Gavin Andresen]

So I've been watching the IP addresses of people getting 5 free bitcoins from the Bitcoin Faucet ( https://freebitcoins.appspot.com/ ).

And I see some... uh, interesting patterns.  Like these successful requests for coins:

Code:

79.117.152.158 - - [21/Jun/2010:12:17:02 -0700] "POST / HTTP/1.1" 200 1234 
79.117.159.197 - - [21/Jun/2010:12:16:24 -0700] "POST / HTTP/1.1" 200 1234 
79.117.135.236 - - [21/Jun/2010:12:10:23 -0700] "POST / HTTP/1.1" 200 1234
79.117.163.238 - - [21/Jun/2010:12:08:50 -0700] "POST / HTTP/1.1" 200 1234
79.117.155.23 - - [21/Jun/2010:12:08:07 -0700] "POST / HTTP/1.1" 200 1234 

My apologies if there actually are a bunch of new bitcoin users using IP addresses in the 79.117 range...  but I'm guessing somebody there is getting more than their fair share of free bitcoins.

There are several suspicious requests from the 192.38.95.* address block, too.

So I've made some changes to the Faucet.  You won't notice them unless you try to cheat; if you do try to cheat, you'll have to solve a CAPTCHA to get coins.

If that doesn't discourage cheating, I'll modify the code so that if it think you're trying to cheat it requires a CAPTCHA and only gives out a bitcoin nickel (0.05 bitcoins)...

[1713899269]

1713899269

[1713899269]

1713899269

[Xunie]

Lol, bitnickel!

Anyhow, I was expecting this.
And what about those using proxies?
I don't wanna be an #@!%!#% here, but ehh... I think the "5 BTC for FREE!" thing, is kinda... flawed...

[Gavin Andresen]

I don't wanna be an #@!%!#% here, but ehh... I think the "5 BTC for FREE!" thing, is kinda... flawed...

"flawed" ??

I've been telling people it is a half-baked, I've-lost-my-friggin-mind idea!

So far, I count it as a big success-- I've learned a lot that will help me with my next Bitcoin-related project, I've made a bunch of people a teeny-tiny bit happier, and I've personally invested just under $1.00 worth of bitcoins over the last two weeks.

I did throw in the towel today and turned on reCAPTCHA for everybody getting bitcoins (it looks like somebody DID bother to write a robot to harvest coins through proxies).  It was fun trying to come up with new, creative ways of detecting cheating, but I have more important things to work on.

[sirius]

http://www.decaptcher.com/


It costs someone $2 per 1000 captchas. So, they could suck out 5000 bitcoins for $2. lol.

But, that should help stop most people

I guess that's why the forum still gets those annoying spam user registrations despite the captcha.

[virtualcoin]

Gavin, why don't you just block all served Bitcoin addresses?
Would it be easy to generate them automatically?

[Gavin Andresen]

Gavin, why don't you just block all served Bitcoin addresses?
Would it be easy to generate them automatically?

It is easy to generate them automatically (it is easy to write code that asks the Bitcoin program to generate and return a new address).

[llama]

Funny how on this forum the same people play both sides of the table--on the one hand, trying to come up with ways to preserve absolute anonymity (e.g. the heroin store thread), and then coming here and trying to do sort of the opposite to protect BTC Faucet. 

I love it 

[satoshi]

Many big ISPs give you a new IP every time you connect, usually in the same class B (a.b.?.?).  Maybe you should have a minimum time between payments per class-B.

If you can't solve the problem, you can always keep lowering the amount of bitcoins given until it's manageable, and always require captcha.

[Gavin Andresen]

Turning on the CAPTCHA for everybody has slowed the flow of coins from the faucet to a very manageable trickle.

Oh, and regarding anonymity versus non-anonymity:  I was careful not to tie IP addresses to Bitcoin addresses when implementing the Bitcoin Faucet.  So I remember that somebody at IP address 96.240.216.119 received bitcoins at 12:30pm today.  And I remember that somebody with Bitcoin address 1P3rpbSybuGgeL1bRwCJFWbn4yBjRNQrbY