C++

Ed25519ph Sign and Verify

See more Ed25519 Examples

Demonstrates how to create an Ed25519ph signature, and then to verify it.

Note: This example requires Chilkat v9.5.0.91 or greater.

C++

#include <CkPrivateKey.h>
#include <CkBinData.h>
#include <CkEdDSA.h>
#include <CkPublicKey.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    //  Use the following test vector from https://www.rfc-editor.org/rfc/rfc8032#page-30

    //     -----TEST abc
    //  
    //     ALGORITHM:
    //     Ed25519ph
    //  
    //     SECRET KEY:
    //     833fe62409237b9d62ec77587520911e
    //     9a759cec1d19755b7da901b96dca3d42
    //  
    //     PUBLIC KEY:
    //     ec172b93ad5e563bf4932c70e1245034
    //     c35467ef2efd4d64ebf819683467e2bf
    //  
    //     MESSAGE (length 3 bytes):
    //     616263
    //  
    //     SIGNATURE:
    //     98a70222f0b8121aa9d30f813d683f80
    //     9e462b469c7ff87639499bb94e6dae41
    //     31f85042463c2a355a2003d062adf5aa
    //     a10b8c61e636062aaad11c2a26083406

    const char *privKeyHex = "833fe62409237b9d62ec77587520911e9a759cec1d19755b7da901b96dca3d42";
    const char *pubKeyHex = "ec172b93ad5e563bf4932c70e1245034c35467ef2efd4d64ebf819683467e2bf";

    CkPrivateKey privKey;
    success = privKey.LoadEd25519(privKeyHex,pubKeyHex);
    if (success == false) {
        std::cout << privKey.lastErrorText() << "\r\n";
        return;
    }

    //  The data to be signed...
    CkBinData bd;
    bd.AppendEncoded("616263","hex");

    CkEdDSA eddsa;
    //  Indicate we want the Ed25519ph instance.
    eddsa.put_Algorithm("Ed25519ph");

    const char *hexSig = eddsa.signBdENC(bd,"hexlower",privKey);

    std::cout << "signature = " << hexSig << "\r\n";

    //  The expected output is: 98a70222f0b8121aa9d30f813d683f80....

    //  Verify the signature..
    CkPublicKey pubKey;
    success = pubKey.LoadEd25519(pubKeyHex);
    if (success == false) {
        std::cout << pubKey.lastErrorText() << "\r\n";
        return;
    }

    bool bVerified = eddsa.VerifyBdENC(bd,hexSig,"hexlower",pubKey);
    if (bVerified == false) {
        std::cout << eddsa.lastErrorText() << "\r\n";
        std::cout << "Failed to verify the signature." << "\r\n";
        return;
    }

    std::cout << "The Ed25519ph signature is verified!" << "\r\n";
    }