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Unicode C++

RSA Encrypt with SHA-256 hash function and SHA-256 mask function

See more RSA Examples

How can this Javascript be duplicated using Chilkat?
function a(e, t) {
                var r = s.pki.publicKeyFromPem(e)
                  , n = r.encrypt(t, "RSA-OAEP", {
                    md: s.md.sha256.create(),
                    mgf1: {
                        md: s.md.sha1.create()
                    }
                });
                return s.util.encode64(n)
            }

Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens, even using the same data and key, the result will be different -- but still valid. One should not expect to get the same output.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkPublicKeyW.h>
#include <CkStringBuilderW.h>
#include <CkCrypt2W.h>
#include <CkByteData.h>
#include <CkRsaW.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkPublicKeyW pubkey;

    CkStringBuilderW sbPem;
    bool bCrlf = true;
    sbPem.AppendLine(L"-----BEGIN PUBLIC KEY-----",bCrlf);
    sbPem.AppendLine(L"MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF",bCrlf);
    sbPem.AppendLine(L"3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA",bCrlf);
    sbPem.AppendLine(L"04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s",bCrlf);
    sbPem.AppendLine(L"Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF",bCrlf);
    sbPem.AppendLine(L"wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE",bCrlf);
    sbPem.AppendLine(L"f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W",bCrlf);
    sbPem.AppendLine(L"SwIDAQAB",bCrlf);
    sbPem.AppendLine(L"-----END PUBLIC KEY-----",bCrlf);

    //  Load the public key object from the PEM. 
    success = pubkey.LoadFromString(sbPem.getAsString());
    if (success == false) {
        wprintf(L"%s\n",pubkey.lastErrorText());
        return;
    }

    const wchar_t *originalData = L"This is the original data to be SHA-256 hashed and RSA encrypted.";

    //  First we SHA-256 hash the original data.
    CkCrypt2W crypt;
    crypt.put_HashAlgorithm(L"SHA-256");
    CkByteData hashBytes;
    success = crypt.HashString(originalData,hashBytes);

    //  Now to RSA encrypt using OAEP padding with SHA-256 for the mask function.
    CkRsaW rsa;
    rsa.put_PkcsPadding(false);
    rsa.put_OaepHash(L"SHA256");
    rsa.UsePublicKey(pubkey);
    rsa.put_EncodingMode(L"base64");

    //  Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens,
    //  even using the same data and key, the result will be different --  but still valid.  One should not expect
    //  to get the same output.
    bool bUsePrivateKey = false;
    const wchar_t *encryptedStr = rsa.encryptBytesENC(hashBytes,bUsePrivateKey);
    if (rsa.get_LastMethodSuccess() == false) {
        wprintf(L"%s\n",rsa.lastErrorText());
        return;
    }

    wprintf(L"Base64 RSA encrypted output: %s\n",encryptedStr);
    }