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Java

Encrypt using Cert to produce -----BEGIN PKCS7----- ... -----END PKCS7-----

See more Encryption Examples

Demonstrates how to encrypt using a certificate to produce output such as:
-----BEGIN PKCS7-----
MIIHPwYJKoZIhvcNAQcEoIIHMDCCBywC ...
...
...
-----END PKCS7-----
The certificate to be used is not your own, but the certificate of the intended recipient of the message.

Chilkat Java Downloads

Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

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

    CkCrypt2 crypt = new CkCrypt2();

    // Specify the encryption to be used.
    // "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped) message.
    crypt.put_CryptAlgorithm("pki");
    crypt.put_Pkcs7CryptAlg("aes");
    crypt.put_KeyLength(128);
    crypt.put_OaepHash("sha256");
    crypt.put_OaepPadding(true);

    // A certificate is needed as the encryption key..
    CkCert cert = new CkCert();
    success = cert.LoadFromFile("qa_data/certs/testCert.pem");
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
        }

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

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

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

    String encryptedStr = crypt.encryptStringENC(toBeEncrypted);
    if (success != true) {
        System.out.println(crypt.lastErrorText());
        return;
        }

    // Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
    CkStringBuilder sb = new CkStringBuilder();
    sb.AppendLine("-----BEGIN PKCS7-----",true);
    sb.Append(encryptedStr);
    sb.AppendLine("-----END PKCS7-----",true);

    String outStr = sb.getAsString();

    System.out.println(outStr);

    // Sample output:

    // -----BEGIN PKCS7-----
    // MIICYQYJKoZIhvcNAQcDoIICUjCCAk4CAQAxggH5MIIB9QIBADCBsTCBmzELMAkGA1UEBhMCR0Ix
    // GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR
    // Q09NT0RPIENBIExpbWl0ZWQxQTA/BgNVBAMTOENPTU9ETyBTSEEtMjU2IENsaWVudCBBdXRoZW50
    // aWNhdGlvbiBhbmQgU2VjdXJlIEVtYWlsIENBAhEAuBl4qE2MODB05C5h53M5UDA4BgkqhkiG9w0B
    // AQcwK6APMA0GCWCGSAFlAwQCAQUAoRgwFgYJKoZIhvcNAQEIMAkGBSsOAwIaBQAEggEAyZejlE37
    // awl0bCWVbOCqf9yLSN17mZRamG8FHDh3nNu11G0+oyJtsPDEnSKsQig0V67MZ+hcWV+uf4ytcjyx
    // H0gs5uex+LwkB+c3ZTOt18IYWFtRilg1HFy1ZN3t0D2QbxYy+i1TXOOwp3gAHL45vRCJ0FbKyQ36
    // pKl0XLe+lRvp2EiJCKVjxtX8VcZOKT4xkG7yOARaCQceth6pA58Dg0yzAz7w4nD2UgAlNzrXG69X
    // e+7e7yfBv47RRqFiQqDpCn+fM/PmFbUyqBppMwc64yP+fJek8VyJw2/UaXWWM4iSKSflk90tiHwf
    // loEU3It4arnSv94fZQo0v129aBqpWzBMBgkqhkiG9w0BBwEwHQYJYIZIAWUDBAECBBCohUgm5qX+
    // TE6PxtPCmWi8gCBgbNg39emAB+AqLozm+vSLjZOGfg3M52gccKUJ8tg8XQ==
    // -----END PKCS7-----
  }
}