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C

PKCS7 Encrypt MIME

See more MIME Examples

Encrypt MIME using a digital certificate to create PKCS7 encrypted S/MIME.

Chilkat C Downloads

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkMime mime;
    HCkCert cert;

    success = FALSE;

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

    mime = CkMime_Create();

    // Build a simple MIME message to be encrypted:
    success = CkMime_AddHeaderField(mime,"Content-Type","text/plain");
    success = CkMime_AddHeaderField(mime,"abc","123");
    CkMime_SetBody(mime,"This is a test");

    // A digital certificate is required to create PKCS7 encrypted MIME.
    // It can come from a variety of sources: .cer file, .pfx file, PEM files,
    // an in-memory representation, or directly from a Windows
    // registry-based certificate store.

    // This example will load a certificate object from a .cer file.
    // Note: Only the public-key is required to encrypt.  (Decryption
    // requires a private key.)

    cert = CkCert_Create();
    success = CkCert_LoadFromFile(cert,"myCert.cer");
    if (success == FALSE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkMime_Dispose(mime);
        CkCert_Dispose(cert);
        return;
    }

    // Encrypt the MIME:
    success = CkMime_Encrypt(mime,cert);
    if (success == FALSE) {
        printf("%s\n",CkMime_lastErrorText(mime));
        CkMime_Dispose(mime);
        CkCert_Dispose(cert);
        return;
    }

    // Display the MIME:
    printf("%s\n",CkMime_getMime(mime));

    // The resulting S/MIME looks something like this:

    // abc: 123
    // Content-Disposition: attachment; filename="smime.p7m"
    // Content-Transfer-Encoding: base64
    // Content-Type: application/x-pkcs7-mime;
    //  name="smime.p7m"
    // 
    // MIICAQYJKoZIhvcNAQcDoIIB8jCCAe4CAQAxggGFMIIBgQIBADBpMFUxCzAJBgNVBAYTAlpBMSUw
    // IwYDVQQKExxUaGF3dGUgQ29uc3VsdGluZyAoUHR5KSBMdGQuMR8wHQYDVQQDExZUaGF3dGUgQ29k
    // ZSBTaWduaW5nIENBAhB4ouTcAmLszrGi170k1deSMA0GCSqGSIb3DQEBAQUABIIBABz59iwVufLZ
    // QIPs0whUYMtBjIQxg5IOCxpoKJeJmLVzu9Q5Q1poxG9uYOveybS9c4wbl5A0DFfKTW5O4HhHcOHW
    // TgcH4iqdwhiFWm/q9d5rjceJWBFQsGOcgoXSU/U2Xp+N47/+Pqyc5XJbxKnOc4YhPzO320JZsNB6
    // p1NGk5SNnWqgbUDmEnfH8ZPHSV7dNi2aiFALYTyLjyp0lqJCsdZ524OPTZFfusrl/9ibPAW7jKuI
    // FgDCcBtRJvolVF8iIHxaTw4rhk0qb1KWzxvB5j9HSLdyIKIPhZbxeS10bx18YkSsBlKfdKRalQag
    // 3oWSRdsK9/N75YHG8Pm+x9BOHUAwYAYJKoZIhvcNAQcBMBkGCCqGSIb3DQMCMA0CAToECAb+toBW
    // txZigDhGZKSpUpuTiWvvSMemX/c79sSnMpuefVwGKFTDgXVLE2SoD5a9Yh5vcG7Mhl2IkilVwOMc
    // fi23+g==


    CkMime_Dispose(mime);
    CkCert_Dispose(cert);

    }