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Unicode C

RSA Encrypt and OpenSSL Decrypt

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Demonstrates how to use Chilkat to RSA encrypt, and then use OpenSSL to decrypt.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkRsaW.h>
#include <C_CkPrivateKeyW.h>
#include <C_CkPublicKeyW.h>
#include <C_CkBinDataW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkRsaW rsa;
    HCkPrivateKeyW privKey;
    HCkPublicKeyW pubKey;
    const wchar_t *plainText;
    BOOL bUsePrivateKey;
    const wchar_t *encryptedStr;
    HCkBinDataW bd;

    success = FALSE;

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

    rsa = CkRsaW_Create();

    privKey = CkPrivateKeyW_Create();
    success = CkRsaW_GenKey(rsa,2048,privKey);
    success = CkPrivateKeyW_SavePkcs8PemFile(privKey,L"qa_output/privKey.pem");

    pubKey = CkPublicKeyW_Create();
    CkPrivateKeyW_ToPublicKey(privKey,pubKey);

    CkRsaW_putEncodingMode(rsa,L"base64");
    plainText = L"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz01234567890";
    bUsePrivateKey = FALSE;
    CkRsaW_UsePublicKey(rsa,pubKey);
    encryptedStr = CkRsaW_encryptStringENC(rsa,plainText,bUsePrivateKey);

    bd = CkBinDataW_Create();
    CkBinDataW_AppendEncoded(bd,encryptedStr,L"base64");
    success = CkBinDataW_WriteFile(bd,L"qa_output/enc.dat");

    // The OpenSSL command to decrypt is:
    // openssl pkeyutl -in enc.dat -inkey privKey.pem -keyform PEM -pkeyopt rsa_padding_mode:pkcs1 -decrypt

    wprintf(L"OK\n");


    CkRsaW_Dispose(rsa);
    CkPrivateKeyW_Dispose(privKey);
    CkPublicKeyW_Dispose(pubKey);
    CkBinDataW_Dispose(bd);

    }