Topic: Need Help Understanding Base58Check Encoding... (Read 1366 times)

Oh, you need to prepend it with a 0x and use base10, not decimal, sorry. So 0x8044d.... convert to base10

When i go to that site and type:

I get:

It means treat that hex string as a really big integer encoded in hex (base16). The easiest thing is to go to a site like http://www.wolframalpha.com/ and type that string followed by " convert to decimal" and it will give you a really large decimal integer. Then you just use that number to do the conversions.

Also, when working with hex, you always need to think of hex not as a string but as bytes and integers.

Sorry, again, I am self-taught when it comes to coding, I do not fully understand the pseudocode... From what I understand I have to change "8044d00f6eb2e5491cd7ab7e7185d81b67a23c4980f62b2ed0914d32b7eb1c55815b0e9051" into a "big integer" and then perform some math on it. How do i convert a plain text string to a "big integer"?

The base58 conversion is specific to Bitcoin. There is pseudocode and a chart of characters here: https://en.bitcoin.it/wiki/Base58Check_encoding#Base58_symbol_chart

OK, I am very close, I am able to reliably produce correct results all the way up to the actual Base58 encoding now.

After finding and adding the checksum to the end of my string from step 3, I have:


Now, how do I do the final Base58 encoding to turn that result into:

Thank you for your reply!

OK, I have xxd and openssl both and I seem to be getting some strange results.

When i create NewFile.txt with the data:

and then run:

NewFile2.txt comes back empty...


Also, if I run:

I get:

Which looks a bit different than the result you got...


EDIT:
Eureka! I needed to add the -p flag! So:

and then

Outputs the correct:

You have definitely placed me on the correct track, thank you so much! Going to see if I can finish the process from here.

The problem isn't your understanding of the process (other than perhaps your understanding of the difference between a hex value and an ASCII string representation of that hex value).

The main problem is in your understanding of the tool you've chosen to use:

https://searchcode.com/codesearch/view/11088282/

Since you don't want to hash the "string", that means that you'll need to create a file that contains ONLY the 32 byte value that you want to hash.

This can be done with xxd if you are using a system that has it...

First use a file editor to create a file that contains the representation that you would have gotten if you had used xxd to convert a file that originally had the value:

You can see here that if you strip out the first column (which is the byte offset into the file where that line of data occurs) and the last column of dots (which is just a placeholder for the ASCII character that each byte represents) the remaining data is your 8044d00f6eb2e5491cd7ab7e7185d81b67a23c4980f62b2ed0914d32b7eb1c5581.

Next, use the "reverse" functionality of xxd to convert back to a binary representation:

We now have a file named "ourNewFileContainingTheDesiredValueToHash" that contains a 32 byte value.

Hash this file, and the result should be b54909e60352ef3ebdd448b65beda938e103624b207c91229bde6e9ba60351e1.  I don't use cmdhashgen, but here's what I get when I use openssl:

Now if I simply captured this output, I'd have an ASCII string representation of "b54909e60352ef3ebdd448b65beda938e103624b207c91229bde6e9ba60351e1".  Since we need to hash this value, we want the binary output from openssl.  openssl has a "-binary" command line option that will output the actual 32 byte value instead of the 64 character ASCII string representation.

We now have a file named "newerFileContainingFinalValueToHash" that contains a 32 byte value. If cmdhashgen does not have the ability to output the 32 byte value, you'll need to repeat the "reverse xxd" process that we did with the previous value to create your file.

I can now hash this file to get the final value that will be used for the checksum:

Is the hash of  when that is hashed as binary data and not as a string.

Bumping in hopes of an answer...

I appreciate the help given so far, I just need to understand this one process.

I understand, and even if you don't feel like explaining it yourself, could you please point me in the right direction by linking me to a resource or giving me proper google search terms that will explain how:

becomes:



Thank you in advance for any help finding the answer here...

I see... Very interesting, thank you for the clarification.

For future reference how does one convert a 64 character alphanumeric hexadecimal representation to the proper 32 byte hexadecimal radix...?

In other words, how do I turn:
into the proper:

so it can be passed to cmdhashgen for hashing...?

Because, when you used the site, you calculated the hash on a single 32 byte value represented in hexadecimal radix.

When you used cmdhashgen, you calculated the hash on a string of 64 alphanumeric characters represented in ASCII.

The site calculated the hash using a 32 byte input of:
0xb54909e60352ef3ebdd448b65beda938e103624b207c91229bde6e9ba60351e1

cmdhashgen calculated the hash of a 64 byte input of:
0x62353439303965363033353265663365626464343438623635626564613933386531303336323 462323037633931323239626465366539626136303335316531

OK, I took the hex string from step 3 (8044D00F6EB2E5491CD7AB7E7185D81B67A23C4980F62B2ED0914D32B7EB1C5581) and ran it through the site which gave me:

Then i took that result and ran it through the site again, I got:

Why is that result different than what I got when I used cmdhashgen to hash the string in SHA256...? Because I took the same string, ran it through cmdhashgen's SHA256 encoder, took that result and repeated but I got:

You have to put the hex string in the text box on the field labeled "binary hash". Then scroll down and find the one labeled "sha256" and copy the hex string and put that in text box in "binary hash". Then scroll down again and the hash in" sha256" is the hash that you want for step 4

I think I understand what you mean now, I want to convert it to the hex form that looks like:

I'm sure that's not the correct string, but that's what it should basically look like?

So far, I have been doing all of these steps using basic DOS/batch scripts that I am writing as I go aside from cmdhashgen which is being used for the SHA256 hashing.

I have some experience and understanding in VBS, C, C++, perl and php.

I tried using that website, but it outputs 16 different fields only one of which contains the word bytes and that just shows the same information from step 5 except uppercase letters have been replaced with lower case letters... Is that what I am looking for...?

Are you using a programming language for this process?

If so, which language, and which packages or libraries are you using?

I'm not sure if I should be presenting suggestions and examples in javascript, java, C, C++, perl, ruby, php, or something else entirely.

No. You are converting it back to binary. What you just need to do is keep the hex string as it is but instead of hashing it as a string, hash it as bytes. Use the website I posted earlier.

Thank you so much for your help, I'm getting closer and closer...

OK, so i THINK I have that step figured out...

If I'm not mistaken, when I convert the hex string from step 5 back to hex bytes it becomes:

Not really sure what to do from here though...



EDIT:
I am definitely doing something wrong because when I put in the hex string from step 5 into the Hexadecimal field at http://convertxy.com/index.php/numberbases/ I get:

Which is exactly the same all the way up until the last 8 sets of numbers...