VanitySearch (Yet another address prefix finder)

[alevlaslo]

thank you, but the speed is 2 times lower

but the probability is higher by 580 thousand times

I deleted all addresses of less than 50 bitcoins, there are 47,000 addresses left, with them the speed drop is only 10%

addresses with less than 50 bitcoins unethical to attack,  people's savings there are

[nc50lc]

is there a 1-day probability of CPU detecting a private key for the full address, or is it zero?
-snip-

It's in the image: half of the search space in 6.31275e+33 years, that's equivalent to 6,312,750,000,000,000,000,000,000,000,000,000 x 2 years.
But since you insist that "it's the same as a lottery" in the deleted thread, you can try and no one will hold you back.

[PawGo]

You've been warned, checking an address on list of address doesn't have O(1) complexity.

I don't understand what this means

https://en.wikipedia.org/wiki/Time_complexity

[bigvito19]

only the CPU has a chance because the addresses were created on the CPU, you can wait for the same thermal noise that Intel uses as a source of entropy.  But the video card will not be able to find the key because the addresses were created on the CPU, and the probability of a random match is negligible. For this reason, the pool LBC finds an addresses, it uses processors, otherwise it would not be possible https://lbc.cryptoguru.org/trophies
 


An example:
We have a hardware capable of generating 1GKey/s and we have an input list of 106 addresses, the following table shows the probability of finding a collision after a certain amount of time:

Time   Probability
1 second   6.8e-34
1 minute   4e-32
1 hour   2.4e-30
1 day   5.9e-29
1 year   2.1e-26
10 years   2.1e-25
1000 years   2.1e-23
Age of earth   8.64e-17
Age of universe   2.8e-16 (much less than winning at the lottery)

LBC generates keys in incremental mode starting from key 1, so it won't find no more collisions really it stop at bit 54 and the same goes with bitcrack too.

[NotATether]

You've been warned, checking an address on list of address doesn't have O(1) complexity.

I don't understand what this means

He means it's not going to take 1 second/millisecond/microsecond to check one address, it could take 28,000,000 time units to check one address which is linear time, it could also take 28,000,000^2 time units - quadratic time, to check a single address, or it could take cubic time, you get the idea. The amount of time it takes depends entirely on the algorithm Jean_Luc is using to check the addresses. I haven't studied the code so I don't know which running time it'll take.

The idea is if you run a computation several thousand times, the time complexity of the algorithm makes a huge difference. An algorithm running in cubic time might never finish doing 28,000,000 runs, but quadratic time might finish that size.

only the CPU has a chance because the addresses were created on the CPU, you can wait for the same thermal noise that Intel uses as a source of entropy.  But the video card will not be able to find the key because the addresses were created on the CPU, and the probability of a random match is negligible.

This assumes that the random number generator on Intel hardware can be programmed to use the same seed, which it can't. Since the seed comes from thermal noise, two Intel processors will never have the same entropy.

Even if vanity generators used Xorshift software RNG that you can set the seed of, vanitysearch can't export the seed that it used. That isn't implemented.

[ymgve2]

why the speed is low, it takes two days for this program to find 8 characters 40 bit, but Pairgen takes 5 seconds

https://github.com/basil00/pairgen/releases

That program is for finding two "similar" BTC addresses, like 53e1f4f491509f9012bd901be5147447f770018b and 53e1f4f491509f9012bd825ce1e9599b253188ef, which is completely different from creating a BTC address with a prefix that you specify.

It is fast because you have no control over what the matching part will be since it uses https://en.wikipedia.org/wiki/Birthday_attack

[bigvito19]

does it not calculate private keys? Is it not possible to select from the list of addresses?

No, that program as is, you can't modify or do anything else with it.

[blue Snow]

Windows 10 always deleting VanitySearch.exe (0 kb) every restart. I have to redownload again and again.

why windows always deleting that file? and how to protect it from the defender?

[TryNinja]

why windows always deleting that file? and how to protect it from the defender?

Ideally, you would move away from Windows.

But you can also whitelist their software on the Windows Defender: Add an exclusion to Windows Security

[nc50lc]

yes, people who create a beautiful address using Bitcrack are very risky

Who'll do that anyways, it's not designed nor advertised to make vanity addresses  

BitCrack is for "bitcracking" addresses' private keys which are purposely generated to be weak.
Like the puzzle transaction (unofficial thread) for example.
BTW, some of those are the private keys with balance that LBC had found over the years.

[xhomerx10]

Does the video card also give random keys or sequential ones?

the point is not in the similarity of addresses, but in the nature of their generation. Vanity generates randomly, so it is safe, and Bitcrack generates sequentially, so it is very easy to repeat the generation of the same address any number of times

and in the opposite direction, on the contrary, it is easier to get accidentally into the key because sequentially it is unrealistic, the universe is too big https://bitcointalk.org/index.php?topic=1306983.msg55448862#msg55448862

 Vanitysearch starts with a seed which, if not specified by the user, is generated randomly.  It proceeds from there searching sequentially.  If you use the same seed, you will get the same results.

[gmaxwell]

Vanitysearch starts with a seed which, if not specified by the user, is generated randomly.  It proceeds from there searching sequentially.  If you use the same seed, you will get the same results.

It's perfectly secure to do this.  Searching this way creates an infinitesimal bias in the keys that are selected (the selected key is more likely to be found after a long run of non-matches than after an immediately prior match) but even where an attacker knows the exact prefix searched for the bias is extremely tiny-- because nearly spaced solutions are extremely unlikely to begin with-- and not exploitable (because you can't search only keys that meet that criteria... since the criteria itself requires generating the pubkeys to check).

[bigvito19]

Vanitysearch starts with a seed which, if not specified by the user, is generated randomly.  It proceeds from there searching sequentially.  If you use the same seed, you will get the same results.

It's perfectly secure to do this.  Searching this way creates an infinitesimal bias in the keys that are selected (the selected key is more likely to be found after a long run of non-matches than after an immediately prior match) but even where an attacker knows the exact prefix searched for the bias is extremely tiny-- because nearly spaced solutions are extremely unlikely to begin with-- and not exploitable (because you can't search only keys that meet that criteria... since the criteria itself requires generating the pubkeys to check).

So its kind of pointless to try to find a address with this if you don't know seed. What exactly is the search space when searching with vanitysearch is it 2^160 or 2^96?

[MrFreeDragon]

Vanitysearch starts with a seed which, if not specified by the user, is generated randomly.  It proceeds from there searching sequentially.  If you use the same seed, you will get the same results.

It's perfectly secure to do this.  Searching this way creates an infinitesimal bias in the keys that are selected (the selected key is more likely to be found after a long run of non-matches than after an immediately prior match) but even where an attacker knows the exact prefix searched for the bias is extremely tiny-- because nearly spaced solutions are extremely unlikely to begin with-- and not exploitable (because you can't search only keys that meet that criteria... since the criteria itself requires generating the pubkeys to check).

So its kind of pointless to try to find a address with this if you don't know seed. What exactly is the search space when searching with vanitysearch is it 2^160 or 2^96?

Vanitysearch starts from the start key(generated based on seed or selected randomly) and then increment it by 1. So, technically there is no limit of the range 2^160 or 2^96, the tool will work till you not stop it.

Imagine the whole private key range from 0 to order (close to 2^256) and the start key marked as s somewhere between 0 and order.

Code:

[0] ......................... s ........................................................ [order]

Even s is very close to the order, it will continue work since the beginning, cause all the private keys are considered by modulo. It is like the infinite loop - while reach the order, start from the beginning.

So, my understanding is that search space is not limited in vanitysearch. It just increments the private key to check by 1 and stop when you stop it (or find the desired address if you select that option)

[gmaxwell]

So its kind of pointless to try to find a address with this if you don't know seed. What exactly is the search space when searching with vanitysearch is it 2^160 or 2^96?

The search space is 2^256, though some keys map to the same addresses. The non-uniformity means that some keys are more likely than others in your search, but all are still possible..

If you were searching for keys beginning with B  and the first letter of the set of keys matched in this pattern  [..B...B..............B....B.............B....BB.B..BBB]  the probability of selecting that last B would be 1 in 54 (because only 1 in 54 starting positions will select it) while it would be 14 out of 54 for the 5th one (because 14 different starting positions will end up there).

But on the real (enormous) range this doesn't really matter... it's just a pedantic detail.

[shlomogold]

is there a 1-day probability of CPU detecting a private key for the full address, or is it zero?

this address was used by scammers to steal bitcoins from the exchange

I'm not sure I understood your question (you can ask me in Russian by messaging me privately so it is not lost in translation),
but if you ask if it were possible to generate the address in one day, then most probably no.
 
And the infamous address you've mentioned, after what I've read, I made my own conclusion, it were not hackers, it was someone
related to mt.gox who stole it and now he's just holding 'cause what else he can do with it

[alevlaslo]

You correctly understood the question, the probability for 1 day is very small

however, if the public key is known, the probability is 10 orders of magnitude higher

[shlomogold]

You correctly understood the question, the probability for 1 day is very small

however, if the public key is known, the probability is 10 orders of magnitude higher

but no one knows the public key to that particular address, so we can only dream about cracking it

[alevlaslo]

this is a different address

[shlomogold]

this is a different address

your screenshot shows the infamous 1Feex with 79,000 bitcoins