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Unicode C

secp256k1 Key Generation and Keccak-256

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Starting in v11.0.0, Chilkat supports both secp256k1 key generation and Keccak-256 directly. These algorithms are typically used for Bitcoin and Ethereum.

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Unicode C
#include <C_CkPrngW.h>
#include <C_CkEccW.h>
#include <C_CkPrivateKeyW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkBinDataW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPrngW fortuna;
    const wchar_t *entropy;
    HCkEccW ecc;
    HCkPrivateKeyW privKey;
    HCkStringBuilderW sb;
    HCkBinDataW bd;

    success = FALSE;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // Create a Fortuna PRNG and seed it with system entropy.
    // This will be our source of random data for generating the ECDSA private key.
    fortuna = CkPrngW_Create();
    entropy = CkPrngW_getEntropy(fortuna,32,L"base64");
    success = CkPrngW_AddEntropy(fortuna,entropy,L"base64");

    ecc = CkEccW_Create();

    // Generate a random ECDSA private key on the secp256k1 curve.
    privKey = CkPrivateKeyW_Create();
    success = CkEccW_GenKey(ecc,L"secp256k1",fortuna,privKey);
    if (success == FALSE) {
        wprintf(L"%s\n",CkEccW_lastErrorText(ecc));
        CkPrngW_Dispose(fortuna);
        CkEccW_Dispose(ecc);
        CkPrivateKeyW_Dispose(privKey);
        return;
    }

    wprintf(L"Successfully generated a sec256k1 key.\n");

    // Show how to compute the Keccak-256 hash in a few ways.
    sb = CkStringBuilderW_Create();
    CkStringBuilderW_Append(sb,L"hello");

    wprintf(L"keccak-256: %s\n",CkStringBuilderW_getHash(sb,L"keccak-256",L"hex_lower",L"utf-8"));

    // Output:
    // keccak-256: 1c8aff950685c2ed4bc3174f3472287b56d9517b9c948127319a09a7a36deac8

    // To keccak-256 hash binary data
    bd = CkBinDataW_Create();
    CkBinDataW_AppendEncoded(bd,L"00010203040506",L"hex");

    wprintf(L"keccak-256: %s\n",CkBinDataW_getHash(bd,L"keccak-256",L"hex_lower"));

    // Output:
    // keccak-256: 801560412425120fa609be232d6fa71c7f64f42aee7977267687dcc0a2f5aa63


    CkPrngW_Dispose(fortuna);
    CkEccW_Dispose(ecc);
    CkPrivateKeyW_Dispose(privKey);
    CkStringBuilderW_Dispose(sb);
    CkBinDataW_Dispose(bd);

    }