Topic: [ANN] Litecoin - a lite version of Bitcoin. Launched! - page 357. (Read 1467253 times)
Thanks, BeeCee1.
Well, at this stage he's rather being helpful. I mean, it would have been much worse if Litecoin had kept this weakness and he or someone else then started exploited it when LTC is more established and/or when the LTC developers are less reactive. Now it's fixed for good, with not really much harm done.
On that note, I would like to survey all the attacks to date on bitcoin-related cryptocurrencies (litecoin, tenebrix, soildcoin and of course bitcoin itself.) Is there a list of attacks so far somewhere? I am aware of the "weaknesses" page on the wiki.
Thanks, Terry.
Well, at this stage he's rather being helpful. I mean, it would have been much worse if Litecoin had kept this weakness and he or someone else then started exploited it when LTC is more established and/or when the LTC developers are less reactive. Now it's fixed for good, with not really much harm done.
On that note, I would like to survey all the attacks to date on bitcoin-related cryptocurrencies (litecoin, tenebrix, soildcoin and of course bitcoin itself.) Is there a list of attacks so far somewhere? I am aware of the "weaknesses" page on the wiki.Well, at this stage he's rather being helpful. I mean, it would have been much worse if Litecoin had kept this weakness and he or someone else then started exploited it when LTC is more established and/or when the LTC developers are less reactive. Now it's fixed for good, with not really much harm done.
On that note, I would like to survey all the attacks to date on bitcoin-related cryptocurrencies (litecoin, tenebrix, soildcoin and of course bitcoin itself.) Is there a list of attacks so far somewhere? I am aware of the "weaknesses" page on the wiki. 
excellent work again - some LTCs are on the way 
Thanks!
I've released Litecoin 0.5.0.6:
- Has the fix to reduce transaction spamming by allowing only 500 bytes of exempted transactions as oppose to 3000 bytes (in Bitcoin)
- Change the priority cutoff of free transaction to 1 litecoin day per 250 bytes.
- Disabled encrypt wallet feature since it's currently broken. encrypted wallets might still have private keys in the clear so be careful if you've already encrypted your wallet.
https://github.com/downloads/coblee/litecoin/litecoin-windows-client-0.5.0.6.zip
I've tested this on testnet. You can see that we now only exempt 3 low priority transactions per block:
http://blockexplorer.sytes.net/chain/LTCtestnet?hi=7447
Everyone, please update to the latest code and this will reduce the transaction spam and slow down the chain growth.
- Has the fix to reduce transaction spamming by allowing only 500 bytes of exempted transactions as oppose to 3000 bytes (in Bitcoin)
- Change the priority cutoff of free transaction to 1 litecoin day per 250 bytes.
- Disabled encrypt wallet feature since it's currently broken. encrypted wallets might still have private keys in the clear so be careful if you've already encrypted your wallet.
https://github.com/downloads/coblee/litecoin/litecoin-windows-client-0.5.0.6.zip
I've tested this on testnet. You can see that we now only exempt 3 low priority transactions per block:
http://blockexplorer.sytes.net/chain/LTCtestnet?hi=7447
Everyone, please update to the latest code and this will reduce the transaction spam and slow down the chain growth.
excellent work again - some LTCs are on the way
It's not much, but at least he's being charged for being a menace. And more profit for miners.
Well, at this stage he's rather being helpful. I mean, it would have been much worse if Litecoin had kept this weakness and he or someone else then started exploited it when LTC is more established and/or when the LTC developers are less reactive. Now it's fixed for good, with not really much harm done. 
I've released Litecoin 0.5.0.6:
- Has the fix to reduce transaction spamming by allowing only 500 bytes of exempted transactions as oppose to 3000 bytes (in Bitcoin)
- Change the priority cutoff of free transaction to 1 litecoin day per 250 bytes.
- Disabled encrypt wallet feature since it's currently broken. encrypted wallets might still have private keys in the clear so be careful if you've already encrypted your wallet.
https://github.com/downloads/coblee/litecoin/litecoin-windows-client-0.5.0.6.zip
I've tested this on testnet. You can see that we now only exempt 3 low priority transactions per block:
http://blockexplorer.sytes.net/chain/LTCtestnet?hi=7447
Everyone, please update to the latest code and this will reduce the transaction spam and slow down the chain growth.
Updated Ozcoin - cheers coblee - Has the fix to reduce transaction spamming by allowing only 500 bytes of exempted transactions as oppose to 3000 bytes (in Bitcoin)
- Change the priority cutoff of free transaction to 1 litecoin day per 250 bytes.
- Disabled encrypt wallet feature since it's currently broken. encrypted wallets might still have private keys in the clear so be careful if you've already encrypted your wallet.
https://github.com/downloads/coblee/litecoin/litecoin-windows-client-0.5.0.6.zip
I've tested this on testnet. You can see that we now only exempt 3 low priority transactions per block:
http://blockexplorer.sytes.net/chain/LTCtestnet?hi=7447
Everyone, please update to the latest code and this will reduce the transaction spam and slow down the chain growth.
How to dump all private keys from a wallet without the mess of txes?
I need to dump some private keys from my spammed wallet but pywallet's dump also "take care" of those txes. Then my server nearly dead because pywallet ate up almost all ram and swap.
the reason I wanted the private keys is my vanity address (below). I didn't save the private keys to another place but i still want to keep the address (took 12hr to generate that.)
I need to dump some private keys from my spammed wallet but pywallet's dump also "take care" of those txes. Then my server nearly dead because pywallet ate up almost all ram and swap.
the reason I wanted the private keys is my vanity address (below). I didn't save the private keys to another place but i still want to keep the address (took 12hr to generate that.)
But my fixes seem to be working. See this last block: http://blockexplorer.sytes.net/block/046ed8ad984dd05e62807eedde8de1706b753f8f0e1b35463c48214882d17b73
The guy has started doing transactions with random amounts. Only of of those were include for free. And there were 3 that's costing him 0.1 LTC each. It's not much, but at least he's being charged for being a menace. And more profit for miners.
The guy has started doing transactions with random amounts. Only of of those were include for free. And there were 3 that's costing him 0.1 LTC each. It's not much, but at least he's being charged for being a menace. And more profit for miners.
He is probably going to figure out what types of transactions get in the block chain for free then try to send a bunch of those, pushing out genuine free transactions. This will make litecoin less inviting to newbies which is bad.
I think we should come up with several algorithms for deciding which transactions are free and let miners decide which one to use (via a config file option)
It would also be good to let miners configure a blacklist of addresses that they don't want included in blocks. I wouldn't want it populated by default, but if a user wanted to they could add addresses to it themselves and those wouldn't go in blocks or be broadcast to other connecting clients.
This is all handled pretty well by the priority of transactions. The attacker will be resending newer coins so the priority will be lower than normal genuine transactions. So normal genuine free transactions will likely be include first before the spam transactions.
But my fixes seem to be working. See this last block: http://blockexplorer.sytes.net/block/046ed8ad984dd05e62807eedde8de1706b753f8f0e1b35463c48214882d17b73
The guy has started doing transactions with random amounts. Only of of those were include for free. And there were 3 that's costing him 0.1 LTC each. It's not much, but at least he's being charged for being a menace. And more profit for miners.
The guy has started doing transactions with random amounts. Only of of those were include for free. And there were 3 that's costing him 0.1 LTC each. It's not much, but at least he's being charged for being a menace. And more profit for miners.
He is probably going to figure out what types of transactions get in the block chain for free then try to send a bunch of those, pushing out genuine free transactions. This will make litecoin less inviting to newbies which is bad.
I think we should come up with several algorithms for deciding which transactions are free and let miners decide which one to use (via a config file option)
It would also be good to let miners configure a blacklist of addresses that they don't want included in blocks. I wouldn't want it populated by default, but if a user wanted to they could add addresses to it themselves and those wouldn't go in blocks or be broadcast to other connecting clients.
Can we find out who is doing this at least ?
How do you propose we do that? No one has step forward and admitted doing this.
But my fixes seem to be working. See this last block: http://blockexplorer.sytes.net/block/046ed8ad984dd05e62807eedde8de1706b753f8f0e1b35463c48214882d17b73
The guy has started doing transactions with random amounts. Only of of those were include for free. And there were 3 that's costing him 0.1 LTC each. It's not much, but at least he's being charged for being a menace. And more profit for miners.
Everyone, please upgrade to the latest code and things will get much better. Thanks.
Can we find out who is doing this at least ?
If the spammer decided to mine his own blocks, would the fact that he is adding power to the network, and would have less frequent spam transactions mean that he is causing less of a problem?
Yes, it would be less of a problem. Let say he has 1% of the overall network hashrate (180 khash/s), he could only send those spammy transactions in 1/100 of the blocks found. This also assumes everyone has updated to the latest code.
I've released Litecoin 0.5.0.6:
- Has the fix to reduce transaction spamming by allowing only 500 bytes of exempted transactions as oppose to 3000 bytes (in Bitcoin)
- Change the priority cutoff of free transaction to 1 litecoin day per 250 bytes.
- Disabled encrypt wallet feature since it's currently broken. encrypted wallets might still have private keys in the clear so be careful if you've already encrypted your wallet.
https://github.com/downloads/coblee/litecoin/litecoin-windows-client-0.5.0.6.zip
I've tested this on testnet. You can see that we now only exempt 3 low priority transactions per block:
http://blockexplorer.sytes.net/chain/LTCtestnet?hi=7447
Everyone, please update to the latest code and this will reduce the transaction spam and slow down the chain growth.
- Has the fix to reduce transaction spamming by allowing only 500 bytes of exempted transactions as oppose to 3000 bytes (in Bitcoin)
- Change the priority cutoff of free transaction to 1 litecoin day per 250 bytes.
- Disabled encrypt wallet feature since it's currently broken. encrypted wallets might still have private keys in the clear so be careful if you've already encrypted your wallet.
https://github.com/downloads/coblee/litecoin/litecoin-windows-client-0.5.0.6.zip
I've tested this on testnet. You can see that we now only exempt 3 low priority transactions per block:
http://blockexplorer.sytes.net/chain/LTCtestnet?hi=7447
Everyone, please update to the latest code and this will reduce the transaction spam and slow down the chain growth.
If the spammer decided to mine his own blocks, would the fact that he is adding power to the network, and would have less frequent spam transactions mean that he is causing less of a problem?
The other disturbing thing I'm seeing is that after the fix has been released, he started sending 2 ltc to himself and maxing out on the 4kb of free transactions per blocks. So you see those blocks with 14 transactions: http://blockexplorer.sytes.net/chain/Litecoin?count=500
13 of these transactions + the generate transaction will max out the amount of free transactions allowed in the block. I know it's the same guy because I followed his transaction back and saw that the same coins were used in both of these attacks. Just look at this transaction: http://blockexplorer.sytes.net/tx/456af81d3bfa3d92ca03e04066aaceca64babeec961dd1474026706eaa4459d9
Some of those coins were used in the 2 ltc spam and the rest were used in the 0.00000001 ltc spams. This guy is really annoying since he seems to have a deep knowledge about how to take advantage of the transaction fee rules.
From the wiki:
This is not a big problem with bitcoins, because Bitcoin has a lot of honest transactions that use up the 4kb in the block, so these spammy low priorties transactions will take forever to get included in a block. So a similar attack on bitcoin is pointless. Since Litecoin is a new chain with not that many honest transactions, it's silly that we are forced to grow at 2.3mb/day by this Litecoin-hater.
I will need to think of a way to combat this. The first thing that comes to mind is to just reduce the 4k exemption for free transactions per day to something much smaller. Maybe instead of allowing 13 of these transactions, we only allow a few to get included in a block. I can reduce the 4k exemption to 1k. This would reduce the chain size increase from 2.3mb/day to 575kb/day. The downside of course is that free transactions might take longer to get written into blocks. I would have to double check, but I don't think the client will let you create transactions without enough fees. So this only applies to people that modify their client to do 0 fees. Let me know what you guys think.
13 of these transactions + the generate transaction will max out the amount of free transactions allowed in the block. I know it's the same guy because I followed his transaction back and saw that the same coins were used in both of these attacks. Just look at this transaction: http://blockexplorer.sytes.net/tx/456af81d3bfa3d92ca03e04066aaceca64babeec961dd1474026706eaa4459d9
Some of those coins were used in the 2 ltc spam and the rest were used in the 0.00000001 ltc spams. This guy is really annoying since he seems to have a deep knowledge about how to take advantage of the transaction fee rules.
From the wiki:
Quote
If the blocksize is over 4kB, free transactions in the above rules are only allowed if the transaction's priority is above a certain level.
So 14 of these transactions are costing him nothing b/c he's sending them to himself. This is not as bad as the first attack, but it will still grow the chain by about 2.3mb a day. (4kb * 576 blocks)This is not a big problem with bitcoins, because Bitcoin has a lot of honest transactions that use up the 4kb in the block, so these spammy low priorties transactions will take forever to get included in a block. So a similar attack on bitcoin is pointless. Since Litecoin is a new chain with not that many honest transactions, it's silly that we are forced to grow at 2.3mb/day by this Litecoin-hater.
I will need to think of a way to combat this. The first thing that comes to mind is to just reduce the 4k exemption for free transactions per day to something much smaller. Maybe instead of allowing 13 of these transactions, we only allow a few to get included in a block. I can reduce the 4k exemption to 1k. This would reduce the chain size increase from 2.3mb/day to 575kb/day. The downside of course is that free transactions might take longer to get written into blocks. I would have to double check, but I don't think the client will let you create transactions without enough fees. So this only applies to people that modify their client to do 0 fees. Let me know what you guys think.
So, it looks like the 0.00000001 transactions are not happening much anymore:
http://blockexplorer.sytes.net/chain/Litecoin?count=100&hi=34342
But we are still seeing the 13 2ltc transactions. I assume people are ok with the decision to change the exempt free coins block size to 1k. I will do that and release a new client soon.
Yes, I only meant deleting the references to the said transactions in the wallet file, not in the blockchain. (How else could it be as large as 320 MB?)
But yeah, I'll probably just create a new wallet. The problem is to avoid using the spam transactions which would result in massive transaction size and transaction fees when moving over the old coins to a new address in the new wallet.
The priority should be to get everyone to update to the newest Litecoin client in order to stop those transactions, they still keep coming every once in a while.
But yeah, I'll probably just create a new wallet. The problem is to avoid using the spam transactions which would result in massive transaction size and transaction fees when moving over the old coins to a new address in the new wallet.
The priority should be to get everyone to update to the newest Litecoin client in order to stop those transactions, they still keep coming every once in a while.
The wallet doesn't contain transactions. Only the blockchain contains transactions. I assumed he was using the world "wallet" loosely as there are 0 transactions to delete from the wallet.dat.
My testnet wallet, dumped:(code snipped)
I only included a couple of the first transactions, in reality there are thousands (tens of thousands in my spammed mainnet wallet).
I stand totally and humbly corrected.
I guess the client is doing that is speed up lookups. Essentially caching transactions it located from the blockchain.If that is the case then there likely is no good way to delete them as client will just re-cache them from the blockchain.
A work around would be to create a new wallet, and transfer coins there. I would wait until the spam issue is resolved to avoid having new wallet spammed though.
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