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Unicode C++

RSA Encrypt RSA/ECB/OAEPWithSHA1AndMGF1Padding

See more RSA Examples

Demonstrates how to RSA encrypt using RSA/ECB/OAEPWithSHA1AndMGF1Padding. Also demonstrates RSA/ECB/OAEPWithSHA-256AndMGF1Padding. Both of these terms are from Java's JCE. Note: In this context, "ECB" doesn't actually mean anything. It's a symmetric cipher mode that doesn't apply (or make sense) in this context.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkRsaW.h>
#include <CkPublicKeyW.h>
#include <CkPrivateKeyW.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.

    CkRsaW rsa;

    // First load a public key object with a public key.
    // In this case, we'll load it from a file.
    CkPublicKeyW pubkey;
    success = pubkey.LoadFromFile(L"qa_data/pem/rsa_public.pem");
    if (success == false) {
        wprintf(L"%s\n",pubkey.lastErrorText());
        return;
    }

    // RSA encryption is limited to small amounts of data. The limit
    // is typically a few hundred bytes and is based on the key size and
    // padding (OAEP vs. PKCS1_5).  RSA encryption is typically used for
    // encrypting hashes or symmetric (bulk encryption algorithm) secret keys.
    const wchar_t *plainText = L"Time is an illusion. Lunchtime doubly so.";

    // Import the public key to be used for encrypting.
    success = rsa.UsePublicKey(pubkey);

    // To get OAEP padding, set the PkcsPadding property equal to false
    rsa.put_PkcsPadding(false);
    rsa.put_OaepHash(L"sha256");

    // Indicate we'll want hex output
    rsa.put_EncodingMode(L"hex");

    // Encrypt..
    bool usePrivateKey = false;
    const wchar_t *encryptedStr = rsa.encryptStringENC(plainText,usePrivateKey);
    wprintf(L"%s\n",encryptedStr);

    // -------------------------------------------------
    // Now decrypt with the matching private key.
    CkRsaW rsa2;

    CkPrivateKeyW privKey;
    success = privKey.LoadEncryptedPem(L"qa_data/pem/rsa_passwd.pem",L"passwd");
    if (success == false) {
        wprintf(L"%s\n",privKey.lastErrorText());
        return;
    }

    success = rsa2.UsePrivateKey(privKey);

    // Make sure we have the same settings used for encryption.
    rsa2.put_PkcsPadding(false);
    rsa2.put_EncodingMode(L"hex");
    rsa2.put_OaepHash(L"sha256");

    const wchar_t *originalStr = rsa2.decryptStringENC(encryptedStr,true);

    wprintf(L"%s\n",originalStr);
    }