(Unicode C) Encrypt/Decrypt using PFX to produce -----BEGIN PKCS7----- ... -----END PKCS7-----

First we encrypt using a certificate + public key to produce output such as:

-----BEGIN PKCS7-----
MIIHPwYJKoZIhvcNAQcEoIIHMDCCBywC ...
...
...
-----END PKCS7-----

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#include <C_CkCrypt2W.h>
#include <C_CkCertW.h>
#include <C_CkStringBuilderW.h>

void ChilkatSample(void)
    {
    HCkCrypt2W crypt;
    HCkCertW cert;
    BOOL success;
    const wchar_t *toBeEncrypted;
    const wchar_t *encryptedStr;
    HCkStringBuilderW sb;
    const wchar_t *outStr;
    BOOL bCrlf;
    HCkCrypt2W decrypt;
    const wchar_t *decryptedText;

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

    crypt = CkCrypt2W_Create();

    // Specify the encryption to be used.
    // "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped) message.
    CkCrypt2W_putCryptAlgorithm(crypt,L"pki");
    CkCrypt2W_putPkcs7CryptAlg(crypt,L"aes");
    CkCrypt2W_putKeyLength(crypt,128);
    CkCrypt2W_putOaepHash(crypt,L"sha256");
    CkCrypt2W_putOaepPadding(crypt,TRUE);

    // A certificate is needed as the encryption key.
    // Althought the PFX contains the associated private key, we don't need it for encryption.
    // (A certificate usually contains the public key by default.)
    cert = CkCertW_Create();
    success = CkCertW_LoadPfxFile(cert,L"qa_data/pfx/cert_test123.pfx",L"test123");
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert));
        CkCrypt2W_Dispose(crypt);
        CkCertW_Dispose(cert);
        return;
    }

    // Tell the crypt object to use the certificate.
    CkCrypt2W_SetEncryptCert(crypt,cert);

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

    // Get the result in multi-line BASE64 MIME format.
    CkCrypt2W_putEncodingMode(crypt,L"base64_mime");

    encryptedStr = CkCrypt2W_encryptStringENC(crypt,toBeEncrypted);
    if (success != TRUE) {
        wprintf(L"%s\n",CkCrypt2W_lastErrorText(crypt));
        CkCrypt2W_Dispose(crypt);
        CkCertW_Dispose(cert);
        return;
    }

    // Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
    sb = CkStringBuilderW_Create();
    CkStringBuilderW_AppendLine(sb,L"-----BEGIN PKCS7-----",TRUE);
    CkStringBuilderW_Append(sb,encryptedStr);
    CkStringBuilderW_AppendLine(sb,L"-----END PKCS7-----",TRUE);

    outStr = CkStringBuilderW_getAsString(sb);

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

    // Sample output:

    // -----BEGIN PKCS7-----
    // MIICXAYJKoZIhvcNAQcDoIICTTCCAkkCAQAxggH0MIIB8AIBADCBrDCBlzELMAkGA1UEBhMCR0Ix
    // GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR
    // Q09NT0RPIENBIExpbWl0ZWQxPTA7BgNVBAMTNENPTU9ETyBSU0EgQ2xpZW50IEF1dGhlbnRpY2F0
    // aW9uIGFuZCBTZWN1cmUgRW1haWwgQ0ECEB6M1ZwZdZU7LrAIdurulmUwOAYJKoZIhvcNAQEHMCug
    // DzANBglghkgBZQMEAgEFAKEYMBYGCSqGSIb3DQEBCDAJBgUrDgMCGgUABIIBAK/BZG/iXJ8az7zL
    // 8EQ77mc+oDPQ4w1hyytK2ip4djkPVvTfYhcoDQ+G/DBU+urJfrVBi5H9gmpXwYyfKlyUxBVRVEJl
    // V/V5QQi4JmNTFbmgWh5tp9zDS98l6A2Va4Zs0Wy/owGLfvwitlxd1dsfVAV2hmBYS24BMpNcty5/
    // 0atcKYmSou13G78ztTKdMy1tECgZy8kerMsPdDQbSxEZkT3KpQ8C5uEQqYF3bIVaeZzha/Ywieh/
    // tvO0T4aAmeJufwkNdVECmU7kuhnNaVPXknFl7jeibTl6zA/VcJKBKcIYT9FRC7KjdooI8q+jtQ/V
    // k6RP4POaowkFg1QWRPEWeqIwTAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBAgQQEEFQduqeJqXQXzy4
    // JpkoDoAgdldJDB9zEkpMpgr5/fR2iLvh5kC6BPfhOYjsawBY4Ok=
    // -----END PKCS7-----

    // ----------------------------------------------------------------------------------------
    // Let's Decrypt the above string.

    // Start with what was produced above..
    CkStringBuilderW_Clear(sb);
    bCrlf = TRUE;
    CkStringBuilderW_AppendLine(sb,L"-----BEGIN PKCS7-----",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"MIICXAYJKoZIhvcNAQcDoIICTTCCAkkCAQAxggH0MIIB8AIBADCBrDCBlzELMAkGA1UEBhMCR0Ix",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"Q09NT0RPIENBIExpbWl0ZWQxPTA7BgNVBAMTNENPTU9ETyBSU0EgQ2xpZW50IEF1dGhlbnRpY2F0",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"aW9uIGFuZCBTZWN1cmUgRW1haWwgQ0ECEB6M1ZwZdZU7LrAIdurulmUwOAYJKoZIhvcNAQEHMCug",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"DzANBglghkgBZQMEAgEFAKEYMBYGCSqGSIb3DQEBCDAJBgUrDgMCGgUABIIBAK/BZG/iXJ8az7zL",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"8EQ77mc+oDPQ4w1hyytK2ip4djkPVvTfYhcoDQ+G/DBU+urJfrVBi5H9gmpXwYyfKlyUxBVRVEJl",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"V/V5QQi4JmNTFbmgWh5tp9zDS98l6A2Va4Zs0Wy/owGLfvwitlxd1dsfVAV2hmBYS24BMpNcty5/",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"0atcKYmSou13G78ztTKdMy1tECgZy8kerMsPdDQbSxEZkT3KpQ8C5uEQqYF3bIVaeZzha/Ywieh/",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"tvO0T4aAmeJufwkNdVECmU7kuhnNaVPXknFl7jeibTl6zA/VcJKBKcIYT9FRC7KjdooI8q+jtQ/V",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"k6RP4POaowkFg1QWRPEWeqIwTAYJKoZIhvcNAQcBMB0GCWCGSAFlAwQBAgQQEEFQduqeJqXQXzy4",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"JpkoDoAgdldJDB9zEkpMpgr5/fR2iLvh5kC6BPfhOYjsawBY4Ok=",bCrlf);
    CkStringBuilderW_AppendLine(sb,L"-----END PKCS7-----",bCrlf);

    decrypt = CkCrypt2W_Create();
    CkCrypt2W_putCryptAlgorithm(decrypt,L"pki");

    // Use the same cert + private key from the PFX above.
    // For decryption, we need the private key.  Given that the certificate was loaded from a PFX,
    // we should already have it.
    success = CkCrypt2W_SetDecryptCert(decrypt,cert);

    CkCrypt2W_putEncodingMode(decrypt,L"base64");
    decryptedText = CkCrypt2W_decryptStringENC(decrypt,CkStringBuilderW_getBetween(sb,L"-----BEGIN PKCS7-----",L"-----END PKCS7-----"));

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


    CkCrypt2W_Dispose(crypt);
    CkCertW_Dispose(cert);
    CkStringBuilderW_Dispose(sb);
    CkCrypt2W_Dispose(decrypt);

    }