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Bitcoin => Bitcoin Discussion => Topic started by: im3w1l on January 21, 2013, 10:11:27 PM



Title: A novel [no] attack against bitcoin
Post by: im3w1l on January 21, 2013, 10:11:27 PM
What if someone were to put illegal information into the blockchain itself? Top secret information or magnet links for example.

EDIT: Not novel, edited title to reflect


Title: Re: A novel attack against bitcoin
Post by: Matthew N. Wright on January 21, 2013, 10:18:53 PM
What if someone were to put illegal information into the blockchain itself? Top secret information or magnet links for example.

I imagine that if someone were able to put magnets in the blockchain, it could power itself!

This topic was covered briefly in this troll thread. https://bitcointalk.org/index.php?topic=11381.0

Bonus: http://pastebin.com/raw.php?i=BUB3dygQ


Title: Re: A novel attack against bitcoin
Post by: adamstgBit on January 21, 2013, 10:29:30 PM
What if someone were to put illegal information into the blockchain itself? Top secret information or magnet links for example.

the blockchain is distributed
if someone puts sensitive information in it, all the nodes will have a copy of this info, so the damage is done and there's nothing they can do about it.
anyway that's that wiki leaks is for. their database is also distributed and equally impossible to control.


Title: Re: A novel attack against bitcoin
Post by: hazek on January 21, 2013, 10:32:51 PM
anyway that's that wiki leaks is for. their database is also distributed and equally impossible to control.

Not to mention a way cheaper way to distribute info.


Title: Re: A novel attack against bitcoin
Post by: hardcore-fs on January 21, 2013, 10:40:08 PM
anyway that's that wiki leaks is for. their database is also distributed and equally impossible to control.

Not to mention a way cheaper way to distribute info.

This can actually be used as a semi-useful attack on the block chain distribution system... just the troll did not think it thru



Title: Re: A novel attack against bitcoin
Post by: human on January 21, 2013, 10:53:42 PM
What if someone were to put illegal information into the blockchain itself? Top secret information or magnet links for example.

nobody would care.


Title: Re: A novel attack against bitcoin
Post by: hardcore-fs on January 21, 2013, 11:02:03 PM
Wrong......


Title: Re: A novel attack against bitcoin
Post by: human on January 21, 2013, 11:06:12 PM
Wrong......

you are right. but since information is a matter of encoding you could also encode illegal stuff into random code and publish an algorithm which decodes this random code... it is simply to complicated. have fun!


Title: Re: A novel attack against bitcoin
Post by: ArticMine on January 21, 2013, 11:11:00 PM
This is mentioned in https://en.bitcoin.it/wiki/Weaknesses#Illegal_content_in_the_block_chain (https://en.bitcoin.it/wiki/Weaknesses#Illegal_content_in_the_block_chain)

My take is that any remaining balance in the transaction associated with the illegal content could become not spendable if clients for fear of the legal consequences do not verify that the coin associated with the illegal content is unspent.

Bitcoin really needs a way to keep the blockchain and traffic at a reasonable size. One step is to purge old transactions and addresses from the chain. To keep bandwith low, something like keyframes (like in videostreams) could be added. The blockchain would contain a keyblock every x blocks which basically is a status-quo snapshot. Then a client would only need to download the latest keyblock and the blocks after that one to be up to date. Those keyblocks would, like transactions, only be valid with x confirmations of the p2p network.

The original paper already covers this.

You only need 80 bytes per block to confirm a block is part of the chain.  These are called the block headers.

Once you have the headers for the entire chain, you can then ask for the blocks starting with the last block and working back.

To verify a transaction, all you need to know is the block that the coin comes from and confirm that it is still an unspent coin.

To do that, you need all blocks between the head of the chain and the transaction that created the coin.



Title: Re: A novel attack against bitcoin
Post by: Littleshop on January 22, 2013, 12:44:03 AM
What if someone were to put illegal information into the blockchain itself? Top secret information or magnet links for example.
It would no longer be top secret.  Problem solved. 


Title: Re: A novel attack against bitcoin
Post by: Spekulatius on January 22, 2013, 02:51:40 AM
What if its constant stream of child porn encrypted in the blocks?


Title: Re: A novel attack against bitcoin
Post by: 01BTC10 on January 22, 2013, 03:47:18 AM
What if its constant stream of child porn encrypted in the blocks?
https://bitcointalk.org/index.php?topic=2901.0


Title: Re: A novel [no] attack against bitcoin
Post by: Murphant on January 22, 2013, 08:44:54 PM
Afaik, similar cases were never actually enforced. Anyone remember the illegal prime number used to decode DVDs?
http://en.wikipedia.org/wiki/Illegal_prime

Songs, t-shirts and mugs were made with that number. Once it's out, nobody can stop it.


Title: Re: A novel [no] attack against bitcoin
Post by: constitution on January 25, 2013, 03:39:54 AM
This thread.. I dont understand.


Title: Re: A novel [no] attack against bitcoin
Post by: Desolator on January 25, 2013, 03:47:46 PM
I feel like this exact topic was brought up like a year ago.


Title: Re: A novel [no] attack against bitcoin
Post by: Elwar on January 25, 2013, 07:46:09 PM
I hid the following in the blockchain:

80085


you are all transporting porn now