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Topic: Game 2: First person to crack this gets 5 BTC [SOLVED] (Read 2450 times)

newbie
Activity: 22
Merit: 0
Damn it!  Embarrassed

Doing the operations was my first idea... I managed to force pywallet to output something in hex, which I beleived, were the numbers:

33 + caea7cc3f8b198101e0f7ffb0eeb2e8c85ce9e72cc628990f30f41183aa6eba58761c239d03ded / 019385 (all in hex)

Doing these operations in gcalctool I ended up with this solution: 80BBC798A19A21A8BCEAA022375B1B73C73EF466CBE5B48D1DB1C195B26CC4603DDC2F897C

However, when this was imported into my wallet.dat, I didn't get the bitcoins (bitcoin was restarted with -rescan). What did I screw up?

The base58-key kontains 5 additional bytes that the hex-version do not. The blue part is the actual key:
80BBC798A19A21A8BCEAA022375B1B73C73EF466CBE5B48D1DB1C195B26CC4603DDC2F897C


Now that I think about it, pywallet probably didn't allow me to import the long key, so I deleted the last 5 bytes... Turns out I should have deleted the first byte and the last 4 bytes instead... Well, anyway, thanks for pointing that out.
sr. member
Activity: 448
Merit: 254
Damn it!  Embarrassed

Doing the operations was my first idea... I managed to force pywallet to output something in hex, which I beleived, were the numbers:

33 + caea7cc3f8b198101e0f7ffb0eeb2e8c85ce9e72cc628990f30f41183aa6eba58761c239d03ded / 019385 (all in hex)

Doing these operations in gcalctool I ended up with this solution: 80BBC798A19A21A8BCEAA022375B1B73C73EF466CBE5B48D1DB1C195B26CC4603DDC2F897C

However, when this was imported into my wallet.dat, I didn't get the bitcoins (bitcoin was restarted with -rescan). What did I screw up?

Ouch, bummer man. Sad

Dani, a private key begins with a 5. That is quite different from a privkey.

A Wallet Import Format key does, but what he posted does indeed contain the hex private key, as Ean explains.
Ean
full member
Activity: 199
Merit: 100
Damn it!  Embarrassed

Doing the operations was my first idea... I managed to force pywallet to output something in hex, which I beleived, were the numbers:

33 + caea7cc3f8b198101e0f7ffb0eeb2e8c85ce9e72cc628990f30f41183aa6eba58761c239d03ded / 019385 (all in hex)

Doing these operations in gcalctool I ended up with this solution: 80BBC798A19A21A8BCEAA022375B1B73C73EF466CBE5B48D1DB1C195B26CC4603DDC2F897C

However, when this was imported into my wallet.dat, I didn't get the bitcoins (bitcoin was restarted with -rescan). What did I screw up?

The base58-key kontains 5 additional bytes that the hex-version do not. The blue part is the actual key:
80BBC798A19A21A8BCEAA022375B1B73C73EF466CBE5B48D1DB1C195B26CC4603DDC2F897C
newbie
Activity: 42
Merit: 0
Congratz Melman
legendary
Activity: 1862
Merit: 1011
Reverse engineer from time to time
Dani, a private key begins with a 5. That is quite different from a privkey.
newbie
Activity: 22
Merit: 0
Damn it!  Embarrassed

Doing the operations was my first idea... I managed to force pywallet to output something in hex, which I beleived, were the numbers:

33 + caea7cc3f8b198101e0f7ffb0eeb2e8c85ce9e72cc628990f30f41183aa6eba58761c239d03ded / 019385 (all in hex)

Doing these operations in gcalctool I ended up with this solution: 80BBC798A19A21A8BCEAA022375B1B73C73EF466CBE5B48D1DB1C195B26CC4603DDC2F897C

However, when this was imported into my wallet.dat, I didn't get the bitcoins (bitcoin was restarted with -rescan). What did I screw up?
member
Activity: 96
Merit: 10
wasn't using the correct order of operations. doh!
sr. member
Activity: 461
Merit: 251
I'm curious Ean, did you purposely camouflage this to look like base64, even the same length as the last one?
Of course.

Yes, very clever Ean - I enjoyed the challenge. Smiley  Thank you!
Ean
full member
Activity: 199
Merit: 100
I'm curious Ean, did you purposely camouflage this to look like base64, even the same length as the last one?
Of course.
sr. member
Activity: 448
Merit: 254
Good job, MelMan2002!

If anyone else is wondering, here's how I replicated the result in PHP:

Code:

// adapted from
// http://darklaunch.com/2009/08/07/base58-encode-and-decode-using-php-with-example-base58-encode-base58-decode
function base58_decode($num) {
    
$alphabet '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';
    
$len strlen($num);
    
$decoded 0;
    
$multi 1;
 
    for (
$i $len 1$i >= 0$i--) {
        
$decoded bcadd($decodedbcmul($multistrpos($alphabet$num[$i])));
        
$multi bcmul($multistrlen($alphabet));
    }
 
    return 
$decoded;
}

function 
base58_encode($num) {
    
$alphabet '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz';
    
$base_count strlen($alphabet);
    
$encoded '';
 
    while (
bccomp($num$base_count) >= 0) {
        
$div bcdiv($num$base_count0);
        
$mod bcsub($numbcmul($base_count$div));
        
$encoded $alphabet[$mod] . $encoded;
        
$num $div;
    }
 
    if (
$num) {
        
$encoded $alphabet[(int)$num] . $encoded;
    }
 
    return 
$encoded;
}

// http://us2.php.net/manual/en/ref.bc.php#99130
function bcdechex($dec) {
    
$last bcmod($dec16);
    
$remain bcdiv(bcsub($dec$last), 16);

    if(
$remain == 0) {
        return 
dechex($last);
    } else {
        return 
bcdechex($remain).dechex($last);
    }
}

$num base58_decode('3HVMPwe1rr96QryQdZtZt1LWfcXnEFSG9rKiRuv8ewxwvUmZMH1zwn');

$num bcdiv($numbase58_decode('Xi4'));
$key bcadd(base58_decode('t'), $num);
echo 
base58_encode($num), "\n";
echo 
substr(bcdechex($num), 264), "\n";

(No warranty or anything on this code Wink)

If I paste the base58 output into the WIF field on Casascius' address utility, appending "?", it calculates the correct private address and adjusts the WIF to match the correct answer.  I'm not sure if this adjustment is because of a bug in my program, or if it's part of the checksum stuff.

The hex goes in fine, although I'll have to read about base58check to see why the substr is necessary.

I'm curious Ean, did you purposely camouflage this to look like base64, even the same length as the last one?  If so it seems to have been effective! Smiley
Ean
full member
Activity: 199
Merit: 100
I used these python functions for the conversion to and from integer numbers:

Code:
__b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
__b58base = len(__b58chars)

def b58encode(v):
    result = []
    while v > 0:
        v, mod = divmod(v, __b58base)
        result.append(__b58chars[mod])
    return ''.join(result[::-1])

def b58decode(v):
    return sum(__b58chars.find(c) * __b58base ** i for i, c in enumerate(v[::-1]))
sr. member
Activity: 461
Merit: 251
I suppose that the other option is to do the division by hand in Base58Check but...that can be rather tricky.
sr. member
Activity: 461
Merit: 251
can you give a bit more details on how to get the right result?
i still can't get it to work  Sad

Details on Base58Check can be found here:
https://en.bitcoin.it/wiki/Base58Check_encoding

Either you find a calculator that can handle a custom number system (my searches were fruitless but I'm sure that they exist) or you convert it to a number system that you can use to do the divide and addition operations.

To convert "Xi4" to base 10, for example, you would have (30*58^2)+(41*58^1)+(3*58^0)=103301
member
Activity: 96
Merit: 10
can you give a bit more details on how to get the right result?
i still can't get it to work  Sad

EDIT: nevermind, got it. good challenge!
Ean
full member
Activity: 199
Merit: 100
Thought I did - have I not?  Shocked
I suppose.
But I can still see them in Electrum ...
sr. member
Activity: 461
Merit: 251
Thought I did - have I not?  Shocked
Ean
full member
Activity: 199
Merit: 100
Read the + and / as mathematical operators.  The rest is in base58Check.

private key: 5KEzAJbyWBoJdjiDAMatvGTjUTurFsyweGknk8r29tUGSS7k5o9
Congratulations!
Now you just have to take the coins.
sr. member
Activity: 461
Merit: 251
Read the + and / as mathematical operators.  The rest is in base58Check.

private key: 5KEzAJbyWBoJdjiDAMatvGTjUTurFsyweGknk8r29tUGSS7k5o9
Ean
full member
Activity: 199
Merit: 100
It's actually closer to the answer than you think.
In a way, you don't even need to decode.
legendary
Activity: 1260
Merit: 1000
Drunk Posts
I can't figure it out.. If thats not base64, I have no idea where to start. I assume you're also using 7-bit since its the same length.
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