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Unicode C++

Create PKCS7 (CMS) EnvelopedData

Encrypt some data to a recipient by creating a PKCS7 (CMS) EnvelopedData structure. The data will be encrypted using a symmetric content-encryption algorithm (e.g., AES), and the randomly generated symmetric key will be encrypted using the recipient’s RSA public key extracted from their X.509 certificate.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkCrypt2W.h>
#include <CkCertW.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkCrypt2W crypt;

    //  Specify the encryption to be used.
    //  "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped-data) message.
    crypt.put_CryptAlgorithm(L"pki");
    crypt.put_Pkcs7CryptAlg(L"aes");
    crypt.put_KeyLength(256);
    crypt.put_OaepHash(L"sha256");
    crypt.put_OaepPadding(true);

    CkCertW cert;

    //  Use a certificate found in the Windows certificate store.
    success = cert.LoadByCommonName(L"My Certificate");
    if (success != true) {
        wprintf(L"%s\n",cert.lastErrorText());
        return;
    }

    //  Tell the crypt object to use the certificate.
    crypt.SetEncryptCert(cert);

    const wchar_t *toBeEncrypted = L"This string is to be encrypted.";

    //  Get the result in multi-line BASE64 MIME format.
    crypt.put_EncodingMode(L"base64_mime");
    crypt.put_Charset(L"utf-8");

    const wchar_t *result = crypt.encryptStringENC(toBeEncrypted);
    if (success != true) {
        wprintf(L"%s\n",crypt.lastErrorText());
        return;
    }

    //  -------------------------------------------------------------------------
    //  See the following example to decrypt what was created in this example
    //  Decrypt PKCS7 (CMS) EnvelopedData
    //  -------------------------------------------------------------------------

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

    //  Sample output:

    //  MIICSgYJKoZIhvcNAQcDoIICOzCCAjcCAQAxggHiMIIB3gIBADCBljCBgTELMAkGA1UEBhMCSVQx
    //  EDAOBgNVBAgMB0JlcmdhbW8xGTAXBgNVBAcMEFBvbnRlIFNhbiBQaWV0cm8xFzAVBgNVBAoMDkFj
    //  dGFsaXMgUy5wLkEuMSwwKgYDVQQDDCNBY3RhbGlzIENsaWVudCBBdXRoZW50aWNhdGlvbiBDQSBH
    //  MwIQPCWvkSv8oQ7xRmEHJ6TzEDA8BgkqhkiG9w0BAQcwL6APMA0GCWCGSAFlAwQCAQUAoRwwGgYJ
    //  KoZIhvcNAQEIMA0GCWCGSAFlAwQCAQUABIIBAKqHAPQNSsQoX7B2NH7QyEOWQRsSVs8oCHXmy8f4
    //  MVZD2er3bvYUCIomxpwbLEAl14qjUIMynahooYGgqip7+4FqL301G+BVjZVfEhHWj+VI1dAWnWuL
    //  VHlvc/pbQNBWqV8rKVJsNIsuAZkdj4WSwLVKxYkYX43B8fh/g71XN2DTJu7Z/824v48KBmgpQBOT
    //  2q7IcDGxNPAFN2p6eavIVGn2LvhEbf/Fszyj+GR5tMcnQP1BOLJ3s3JzUBbvj8hcZrF1Vhl9HnTU
    //  YQx8G/KdW1mR+Wlhl3BWoK0LYKRTbnTx2BXOs0CY1SXOAdhKr01ZYjA+xW4nGzY0lfXS9QZjh9gw
    //  TAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBKgQQw0xTbfmnt0zjWHo5SaQIp4AgxTVY9E/Ncqy6t+RM
    //  8y4c3Av62/wB8IpPUEmtM2OeuZo=
    }