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C++

Create PKCS7 Attached/Opaque Signature (S/MIME)

See more MIME Examples

Create an S/MIME message with a PKCS7 attached/opaque signature.

Chilkat C++ Downloads

C++
#include <CkMime.h>
#include <CkCert.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    CkMime mime;

    //  Load a certificate w/ private key for signing.
    //  There are many ways of getting a certificate object:
    //  from a pfx file, from .cer and private-key files, from the
    //  Windows registry-based certificate stores, etc.
    //  Load a PFX file into a certificate object.
    CkCert cert;
    const char *pfxFilepath = "pfxFiles/something.pfx";
    const char *pfxPassword = "secret";
    success = cert.LoadPfxFile(pfxFilepath,pfxPassword);
    if (success == false) {
        std::cout << cert.lastErrorText() << "\r\n";
        return;
    }

    //  Create a very simple MIME message to be signed:
    success = mime.AddHeaderField("Subject","This is a test");
    success = mime.AddHeaderField("MyCustomHeader","abc123");
    mime.put_ContentType("text/plain");
    mime.SetBody("This is a plain-text body.");

    //  Examine the MIME prior to signing:
    std::cout << "--- MIME prior to signing ---" << "\r\n";
    std::cout << mime.getMime() << "\r\n";

    //  The MIME prior to signing looks like this:
    //  -------------------------------------------------------------------------------

    //  Subject: This is a test
    //  MyCustomHeader: abc123
    //  Content-Type: text/plain
    //  
    //  This is a plain-text body.

    //  -------------------------------------------------------------------------------

    //  The default hash algorithm used in the signing process is "SHA1".
    //  To change it, set the SigningHashAlg property:
    mime.put_SigningHashAlg("SHA256");

    //  Convert the MIME to PKCS7 signed-data.
    success = mime.ConvertToSigned(cert);
    if (success == false) {
        std::cout << mime.lastErrorText() << "\r\n";
        return;
    }

    //  Examine the signed MIME
    std::cout << "--- MIME converted to PKCS7 signed-data ---" << "\r\n";
    std::cout << mime.getMime() << "\r\n";

    //  The MIME after signing looks like this:
    //  -------------------------------------------------------------------------------

    //  Subject: This is a test
    //  MyCustomHeader: abc123
    //  Content-Disposition: attachment; filename="smime.p7m";
    //  Content-Transfer-Encoding: base64
    //  Content-Type: application/x-pkcs7-mime;
    //   name="smime.p7m"; smime-type="signed-data";
    //  
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    //  aQRnU3ViamVjdDogVGhpcyBpcyBhIHRlc3QNCk15Q3VzdG9tSGVhZGVyOiBhYmMxMjMNCkNvbnRl
    //  bnQtVHlwZTogdGV4dC9wbGFpbg0KDQpUaGlzIGlzIGEgcGxhaW4tdGV4dCBib2R5LqCCCaAwggRm
    //  MIIDTqADAgECAhBEvgyLUAAktBHTNi3gs18bMA0GCSqGSIb3DQEBBQUAMIGVMQswCQYDVQQGEwJV
    //  UzELMAkGA1UECBMCVVQxFzAVBgNVBAcTDlNhbHQgTGFrZSBDaXR5MR4wHAYDVQQKExVUaGUgVVNF
    //  UlRSVVNUIE5ldHdvcmsxITAfBgNVBAsTGGh0dHA6Ly93d3cudXNlcnRydXN0LmNvbTEdMBsGA1UE
    //  AxMUVVROLVVTRVJGaXJzdC1PYmplY3QwHhcNOTkwNzA5MTgzMTIwWhcNMTkwNzA5MTg0MDM2WjCB
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    //  AQ8AMIIBCgKCAQEAzqqBP6OjYXiqMQBVlRGeJw8fHN86m4JoMMBKYR3xLw76vnn3pSPvVVGWhM3b
    //  47luPjHYCiBnx/TZv5TrRwQ+As4qol2HBAn2MJ0Yipeyqhz8QdKhNsv7PZG659lwNfrk55DDm6Ob
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    //  DwQEAwIBxjAPBgNVHRMBAf8EBTADAQH/MB0GA1UdDgQWBBTa7WR0FJwUPKvdmam9WyhNizzJ2DBC
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    //  A4IBDwAwggEKAoIBAQC5ueUJPjI74J5Yavc3JUCWHEMMd2C9T+4VDuUcN7vzYuIOjsyV1yhzAl8+
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    //  nnYEFScZho3knWoBYC4841sdUay70pqluo2Y1CBbx5t+zYPXit370hEGzKLNK6XRTevcVQQMvL/f
    //  d/gz241M8KBT8yvqTAjv6NJz9tHNUqhYO5mTT65nsIwKQ5/T8L+hsOHi4VM2QdVW6ZD9jrfPIfES
    //  yOyfXCx2l9oEHfB3gwgdYQ4Mq9hRG77mIc9H+pw1V0yMmQmEVs0LP6hvAgMBAAGjggFuMIIBajAf
    //  BgNVHSMEGDAWgBTa7WR0FJwUPKvdmam9WyhNizzJ2DAdBgNVHQ4EFgQUBMe/RfjpWAOjAMHml1qw
    //  DvPa4OowDgYDVR0PAQH/BAQDAgeAMAwGA1UdEwEB/wQCMAAwEwYDVR0lBAwwCgYIKwYBBQUHAwMw
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    //  

    //  -------------------------------------------------------------------------------
    }