(C) Encrypt MIME using RSAES-OAEP with SHA256 and AES-128 content encryption

Demonstrates how to encrypt MIME using RSAES-OAEP with SHA256 and AES-128 content encryption.

Note: This example requires Chilkat v9.5.0.67 or greater.

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#include <C_CkMime.h>
#include <C_CkStringBuilder.h>
#include <C_CkCert.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkMime mime;
    HCkMime part0;
    HCkMime part1;
    HCkStringBuilder sbMime;
    HCkCert cert;

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

    mime = CkMime_Create();

    // Create a MIME message to encrypt.
    CkMime_NewMultipartMixed(mime);
    CkMime_AddHeaderField(mime,"someHeader1","Some value 1");
    CkMime_AddHeaderField(mime,"someHeader2","Some value 2");

    part0 = CkMime_Create();
    CkMime_AddHeaderField(part0,"hdrA","Some value A");
    CkMime_AddHeaderField(part0,"hdrB","Some value B");
    CkMime_putContentType(part0,"text/plain");
    CkMime_SetBody(part0,"This is the plain-text body.");

    part1 = CkMime_Create();
    CkMime_AddHeaderField(part1,"hdrX","Some value X");
    CkMime_AddHeaderField(part1,"hdrY","Some value Y");
    CkMime_putContentType(part1,"text/xml");
    CkMime_SetBody(part1,"<a>This is the XML body</a>");

    CkMime_AppendPart(mime,part0);
    CkMime_AppendPart(mime,part1);

    // The MIME to be encrypted:
    sbMime = CkStringBuilder_Create();
    CkMime_GetMimeSb(mime,sbMime);
    printf("%s\n",CkStringBuilder_getAsString(sbMime));

    // 	Content-Type: multipart/mixed; boundary="------------080303020600020604010008"
    // 	someHeader1: Some value 1
    // 	someHeader2: Some value 2
    // 
    // 	--------------080303020600020604010008
    // 	hdrA: Some value A
    // 	hdrB: Some value B
    // 	Content-Type: text/plain
    // 
    // 	This is the plain-text body.
    // 	--------------080303020600020604010008
    // 	hdrX: Some value X
    // 	hdrY: Some value Y
    // 	Content-Type: text/xml
    // 
    // 	<a>This is the XML body</a>
    // 	--------------080303020600020604010008--
    // 

    // Load an RSA-based certificate.
    // (Encrypting MIME only requires the public key.  Decrypting MIME requires the private key.)
    cert = CkCert_Create();
    success = CkCert_LoadFromFile(cert,"qa_data/rsaes-oaep/cert.pem");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkMime_Dispose(mime);
        CkMime_Dispose(part0);
        CkMime_Dispose(part1);
        CkStringBuilder_Dispose(sbMime);
        CkCert_Dispose(cert);
        return;
    }

    // Set the email object properties to indicate the desired encryption.
    CkMime_putPkcs7CryptAlg(mime,"aes");
    // If AES-256 is desired, set the following property to 256.
    CkMime_putPkcs7KeyLength(mime,128);
    CkMime_putOaepPadding(mime,TRUE);
    // Other choices for the OAEP hash algorithm are "sha1", "sha384", and "sha512"
    CkMime_putOaepHash(mime,"sha256");

    // Encrypt the MIME (to create S/MIME, which stands for "Secure MIME")
    success = CkMime_Encrypt(mime,cert);
    if (success != TRUE) {
        printf("%s\n",CkMime_lastErrorText(mime));
        CkMime_Dispose(mime);
        CkMime_Dispose(part0);
        CkMime_Dispose(part1);
        CkStringBuilder_Dispose(sbMime);
        CkCert_Dispose(cert);
        return;
    }

    printf("---------------\n");
    printf("Encrypted MIME:\n");
    printf("---------------\n");
    printf("%s\n",CkMime_getMime(mime));

    printf("Success.\n");

    // ---------------------------------------------------
    // This is sample output for RSAES-OAEP encrypted MIME:
    // ---------------------------------------------------

    // Content-Type: application/x-pkcs7-mime; name="smime.p7m"; smime-type="enveloped-data"
    // someHeader1: Some value 1
    // someHeader2: Some value 2
    // Content-Disposition: attachment; filename="smime.p7m"
    // Content-Transfer-Encoding: base64
    // 
    // MIIDvAYJKoZIhvcNAQcDoIIDrTCCA6kCAQAxggGgMIIBnAIBADB1MGgxCzAJBgNVBAYTAlVTMQsw
    // CQYDVQQIDAJJTDEQMA4GA1UEBwwHV2hlYXRvbjEhMB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQ
    // dHkgTHRkMRcwFQYDVQQDDA5DaGlsa2F0V2lkZ2V0cwIJAMRwugDmvniwMBwGCSqGSIb3DQEBBzAP
    // oA0wCwYJYIZIAWUDBAIBBIIBAFaUL1ga1bOrdqYKcMm+FHUacBvzfBxk0fnPA0AMBdN8BvTWT3CN
    // YuqBhjOGyq0FpYD9pVZybUuFMCVsVyIW2O62HnsOK58YaPEUUcdH2sI+yjqX9UAn0P0nVDSsVdeK
    // W8x9kMfZg+3UP+y1q+lu7VRJO3f2C9oLQpTkc4VW4n7UOcUI0waykLCjCTL8lFDb7/J3GeuMKyhH
    // 5riNz50kpbzqn7m2Ks9yA+QmcTdXclclGFr2vwEUFzSdT2pxh/vaUrogCxkYWbQ2eV7vZg6O4kV0
    // aqHBqySkPTAzHKiHH8K8GVdlTuJ8350CpICa4T8w7/Ht5I7dyOPPKy4C+rVtrvcwggH+BgkqhkiG
    // 9w0BBwEwHQYJYIZIAWUDBAECBBDTC2WNBN+z2I47/4Feu9YqgIIB0MZvl3nC/q/Wzil6HtfQTr12
    // Q5moHY+ORzAa1P9XvX2ZUFhW530mV395mQw/A4o4ekmX9eRPEZquYzZPLT8hNeZIuNdhpcSQUmad
    // rKnKkR0wKJ3jJ3LhOIohVBQSYs8kVDZKq6lJBIznlsurFelZoNEhyRschhteDZx5rb7fCe8c2+/O
    // DHxaqaHCAzm/Bd7kcg6FFfuTZy3tu0PgP5IsXN4OFA3kkvwjAs4XsVS8jdIcmDNBkYieE8WmJOIm
    // Mz7mh/CHWLgWfGKa0Dkb9RcbFgLwYNT3GzuXFw9XPbKkEZjEAtJajWbN6P0WQl96YYd9qZxUpGxZ
    // zjTHEYzViUdUXolfpLufttrRXyxN1RFWhNFMFbv66xYqklMSgpdM/Mbk+EuvX6eXayDPvDBpfYMw
    // NoRAzv1Ony2c0ez9rBemJICicxAzpuvHbRxdjYs63Dnv+TYgpBK12AxWWpPIjXvw0WQKgTC3Tg8s
    // EnuGhpENqso/clJBEBSn4+2WhYtYbdI5sVme67lvqQl1Xxy3r18SWaQbyDOwgYi1E+54lMDOxMy0
    // y0FPHk5pP45DnXWj+XORPp5LhuZr5mf62YOXSSUwR5P0cXy4Rc+pN5lhRQPCf5z2


    CkMime_Dispose(mime);
    CkMime_Dispose(part0);
    CkMime_Dispose(part1);
    CkStringBuilder_Dispose(sbMime);
    CkCert_Dispose(cert);

    }