Sha256 and ripemd160 hash implementation in C language.

Question

0.00/5 (No votes)

See more:

I want some help with the implementation of sha256 and ripemd160 hash in the c program. Does anyone know how can I perform sha256 on a char array? I wrote a code

<pre>#include <stdio.h>
#include <string.h>
#include <openssl/sha.h>
 
int main (void) {
	const char s[131] = "0450863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B23522CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6";
	unsigned char *d = SHA256(s, strlen(s), 0);
 
	int i;
	for (i = 0; i < SHA256_DIGEST_LENGTH; i++)
		printf("%02x", d[i]);
	putchar('\n');
 
	return 0;
}

the problem is this code gives a wrong output when the length of char array s increases.
If you replace the public key with any string which is small enough it will work correctly.
But I can't figure out how can I do it with big char arrays. Any suggestions or code would be helpful.
And also want help with how to do ripemd160 hash on the resulting outcome of sh256 in c language.
You can compile the above code with this command

gcc test.c -lssl -lcrypto

What I have tried:

<pre lang="text"><pre>include <stdio.h>
#include <string.h>
#include <openssl/sha.h>
 
int main (void) {
	const char s[131] = "036EAF0968AA895ADDFEE599566F0B880242461D1377F4887C9B84631E13067B96";
	unsigned char *d = SHA256(s, strlen(s), 0);
 
	int i;
	for (i = 0; i < SHA256_DIGEST_LENGTH; i++)
		printf("%02x", d[i]);
	putchar('\n');
 
	return 0;
}

the outcome of this cod is

d1b9207a2144271601f7fab515d60aeef167c919a1f78560314106576ada35ec

which is correct.
but dose not work with uncompressed form of public key of bitcoin.

Posted 19-Mar-20 4:31am

Asish6542165

Updated 19-Mar-20 5:07am

Add a Solution

1 solution

Add a Solution

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Accepted Answer · 2020-03-19T05:08:00

Solution 2

You seem to be a little confused:

Quote:
If you replace the public key with any string which is small enough it will work correctly.

SHA is a hashing algorithm, not an encryption algorithm - it doesn't use a key, public or private.
Hashing algorithms always generate a value with the same size - that's the whole point - and they do that by "throwing away" information, and as such are not "reversible": you cannot guarantee to get the original input back from the output value. Encryption algorithms are different - they use a key to make the output data much, much harder to reverse back to get the original input.
If you code is any good for generating SHA values, then it should work for any size input. So at a guess, you are assuming something wrongly, or trying to do something that isn't actually possible.

Posted 19-Mar-20 5:08am

OriginalGriff

Comments

Asish6542165 19-Mar-20 11:12am

can you suggest me a code for performing sha256 on char array in c

OriginalGriff 19-Mar-20 11:25am

You already have code for that:

SHA256(s, strlen(s), 0);

It's part of the OpenSSL library, and that is what it does!
https://www.openssl.org/docs/man1.0.2/man3/SHA256.html

Asish6542165 19-Mar-20 11:26am

then why does it go wrong when I give it a char array of bigger size

OriginalGriff 19-Mar-20 11:30am

How would I know? I can't see the code you use that uses a longer array!
And how do you know it goes wrong?
How are you testing it?

Asish6542165 19-Mar-20 11:31am

yes i have tested it

it is the same code that you are looking for with the longer string 0450863AD64A87AE8A2FE83C1AF1A8403CB53F53E486D8511DAD8A04887E5B23522CD470243453A299FA9E77237716103ABC11A1DF38855ED6F2EE187E9C582BA6

OriginalGriff 19-Mar-20 11:42am

I didn't ask "if" you had tested it, I asked "how" you tested it.

That's probably pretty fundamental, given that this is code that has been used by thousands - probably millions - of other users without any problems.

Asish6542165 19-Mar-20 11:40am

when I compile it it gives me this output

37a0df85d5ccf7cb5f92b53aa3f223d76c115a844ed52d8978deecd2ecb3e406

but the correct output should be

32511e82d56dcea68eb774094e25bab0f8bdd9bc1eca1ceeda38c7a43aceddce

OriginalGriff 19-Mar-20 11:54am

How can I help you when you don't answer questions?

Asish6542165 19-Mar-20 11:58am

I compiled the code on my kali machine. I used the same string on this website to generate sha https://emn178.github.io/online-tools/sha256.html but the output of my code and this website are totally different.

OriginalGriff 19-Mar-20 12:30pm

That tells us nothing about the code you used to generate the hash value you are comparing the "good" one with.
What part of "I can't see your code unless you show it here" is difficult for you to understand?

Sha256 and ripemd160 hash implementation in C language.

1 solution

Solution 2

Add your solution here

Preview 0

Sha256 and ripemd160 hash implementation in C language.

1 solution

Solution 2

Add your solution here

Preview 0

Existing Members

...or Join us