Unicode C

RSA Sign with PKCS8 Encrypted Key

See more RSA Examples

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature. Unicode C

#include <C_CkPrivateKeyW.h>
#include <C_CkRsaW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPrivateKeyW pkey;
    HCkRsaW rsa;
    const wchar_t *strData;
    const wchar_t *hexSig;

    success = FALSE;

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

    pkey = CkPrivateKeyW_Create();

    // Load the private key from an RSA PEM file:
    success = CkPrivateKeyW_LoadPkcs8EncryptedFile(pkey,L"privateKey.key",L"myPassword");

    rsa = CkRsaW_Create();

    // Import the private key into the RSA object:
    success = CkRsaW_UsePrivateKey(rsa,pkey);
    if (success == FALSE) {
        wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
        CkPrivateKeyW_Dispose(pkey);
        CkRsaW_Dispose(rsa);
        return;
    }

    // Return the signature in hex
    CkRsaW_putEncodingMode(rsa,L"hex");

    strData = L"This is the string to be signed.";

    // Sign the string using the sha-1 hash algorithm.
    // Other valid choices are "md2", "sha256", "sha384", "sha512",  and "md5".
    hexSig = CkRsaW_signStringENC(rsa,strData,L"sha-1");

    wprintf(L"%s\n",hexSig);


    CkPrivateKeyW_Dispose(pkey);
    CkRsaW_Dispose(rsa);

    }