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Unicode C

Duplicate PHP RSA Encryption

See more RSA Examples

Demonstrates how to duplicate the following PHP function.

Chilkat Unicode C Downloads

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

void ChilkatSample(void)
    {
    BOOL success;
    const wchar_t *rsaMOD;
    const wchar_t *rsaEXP;
    HCkBinDataW bdMod;
    HCkBinDataW bdExp;
    HCkXmlW xml;
    HCkPublicKeyW pubkey;
    HCkRsaW rsa;
    const wchar_t *plainText;
    const wchar_t *cipherText;

    success = FALSE;

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

    // Duplicate the following PHP code:
    // 
    //    public function encryptRSA($plainText,$rsaMOD,$pubKEY){
    //         $rsa  = new RSA();
    //         $rsa->setEncryptionMode(RSA::ENCRYPTION_PKCS1);
    //         $publicKey = [
    //             'e' => new BigInteger($pubKEY,16),
    //             'n' => new BigInteger($rsaMOD,16)
    //         ];
    // 		
    //         $rsa->loadKey($publicKey);
    //         $ciphertext = $rsa->encrypt($plainText);
    //         return bin2hex($ciphertext);
    //     }
    // 
    //     $plainText="key=abcdefghijkmnopq&iv=abcdefghijkmnopq&h=12345678&s=12345678"
    //     $rsaMOD="F0946D8F05604809E24B8CFFD30349CEA9E5F4D320BFD9E9AA1B088863F02C43E7997D37A3E27B4F8F359F1744DB6B20A437067C0D325A80660D12FF56A57673"
    //     $pubKEY="010001"

    // We have the RSA modulus in hex
    rsaMOD = L"F0946D8F05604809E24B8CFFD30349CEA9E5F4D320BFD9E9AA1B088863F02C43E7997D37A3E27B4F8F359F1744DB6B20A437067C0D325A80660D12FF56A57673";

    // The RSA exponent in hex is "010001", which is 65537 in decimal.  It's typically the exponent that is always used.
    rsaEXP = L"010001";

    // Get the RSA modulus and exponent in base64.
    bdMod = CkBinDataW_Create();
    bdExp = CkBinDataW_Create();
    success = CkBinDataW_AppendEncoded(bdMod,rsaMOD,L"hex");
    success = CkBinDataW_AppendEncoded(bdExp,rsaEXP,L"hex");

    // Build the XML representation of the RSA public key
    xml = CkXmlW_Create();
    CkXmlW_putTag(xml,L"RSAPublicKey");
    CkXmlW_UpdateChildContent(xml,L"Modulus",CkBinDataW_getEncoded(bdMod,L"base64"));
    CkXmlW_UpdateChildContent(xml,L"Exponent",CkBinDataW_getEncoded(bdExp,L"base64"));

    // Load the RSA public key into a Chilkat public key object.
    pubkey = CkPublicKeyW_Create();
    success = CkPublicKeyW_LoadFromString(pubkey,CkXmlW_getXml(xml));

    // Setup the RSA object for encryption and do it..
    rsa = CkRsaW_Create();
    CkRsaW_putVerboseLogging(rsa,TRUE);
    success = CkRsaW_UsePublicKey(rsa,pubkey);

    // Use PKCSv1.5 padding
    CkRsaW_putPkcsPadding(rsa,TRUE);

    // Encrypt and return the string as hex.
    CkRsaW_putEncodingMode(rsa,L"hex");
    plainText = L"key=abcdefghijkmnopq&iv=abcdefghijkmnopq&h=12345678&s=12345678";
    cipherText = CkRsaW_encryptStringENC(rsa,plainText,FALSE);
    if (CkRsaW_getLastMethodSuccess(rsa) == FALSE) {
        wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
        CkBinDataW_Dispose(bdMod);
        CkBinDataW_Dispose(bdExp);
        CkXmlW_Dispose(xml);
        CkPublicKeyW_Dispose(pubkey);
        CkRsaW_Dispose(rsa);
        return;
    }

    // Note: The PKCSv1_5 padding incorporates random bytes.  Therefore, the RSA encryption will produce different results each time -- all of which are valid 
    // and decrypt correctly to the same original text.
    wprintf(L"%s\n",cipherText);


    CkBinDataW_Dispose(bdMod);
    CkBinDataW_Dispose(bdExp);
    CkXmlW_Dispose(xml);
    CkPublicKeyW_Dispose(pubkey);
    CkRsaW_Dispose(rsa);

    }