(C) Duplicate OpensSSL to Sign File and Output Binary DER

This example duplicates the following:

openssl smime -sign -in INPUT.xml -signer SIGN.PEM -passin pass:MYPASS -outform der -binary -nodetach -out SIGNED.P7M

Note: Although "smime" is the OpenSSL command, it's not actually producing S/MIME. The arguments "-outform der -binary" indicates that the output is binary DER (i.e. the PKCS7 binary signature). The input can be any type of file: XML, PDF, JPG, ... *anything*...

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#include <C_CkCrypt2.h>
#include <C_CkPem.h>
#include <C_CkPrivateKey.h>
#include <C_CkCert.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    HCkPem pem;
    BOOL success;
    HCkPrivateKey privkey;
    HCkCert cert;
    HCkCert certFromP12;

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

    crypt = CkCrypt2_Create();

    // Load the PEM containing cert + private key.
    pem = CkPem_Create();
    success = CkPem_LoadPemFile(pem,"qa_data/pem/myPem.pem","password");
    if (success != TRUE) {
        printf("%s\n",CkPem_lastErrorText(pem));
        CkCrypt2_Dispose(crypt);
        CkPem_Dispose(pem);
        return;
    }

    privkey = CkPem_GetPrivateKey(pem,0);
    if (CkPem_getLastMethodSuccess(pem) != TRUE) {
        printf("%s\n",CkPem_lastErrorText(pem));
        CkCrypt2_Dispose(crypt);
        CkPem_Dispose(pem);
        return;
    }

    cert = CkPem_GetCert(pem,0);
    if (CkPem_getLastMethodSuccess(pem) != TRUE) {
        CkPrivateKey_Dispose(privkey);
        printf("%s\n",CkPem_lastErrorText(pem));
        CkCrypt2_Dispose(crypt);
        CkPem_Dispose(pem);
        return;
    }

    success = CkCrypt2_SetSigningCert2(crypt,cert,privkey);
    if (success != TRUE) {
        CkPrivateKey_Dispose(privkey);
        CkCert_Dispose(cert);
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCrypt2_Dispose(crypt);
        CkPem_Dispose(pem);
        return;
    }

    CkPrivateKey_Dispose(privkey);
    CkCert_Dispose(cert);

    // Alternatively, we could use a .pfx/.p12 file.
    // (Chilkat also supports other formats/sources for cert/private keys...)
    certFromP12 = CkCert_Create();
    success = CkCert_LoadPfxFile(certFromP12,"qa_data/p12/myP12.p12","password");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(certFromP12));
        CkCrypt2_Dispose(crypt);
        CkPem_Dispose(pem);
        CkCert_Dispose(certFromP12);
        return;
    }

    // The certificate, when loaded from a .pfx/.p12, will automatically 
    // include the associated private key, assuming it's present in the .p12.
    // We don't have to explicitly provide the private key as in the
    // lines of code above that use the PEM file.
    success = CkCrypt2_SetSigningCert(crypt,certFromP12);
    if (success != TRUE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCrypt2_Dispose(crypt);
        CkPem_Dispose(pem);
        CkCert_Dispose(certFromP12);
        return;
    }

    // Create the opaque signature (PKCS7 binary DER that contains both the signature and original file data).
    success = CkCrypt2_CreateP7M(crypt,"qa_data/infile.anything","qa_output/outfile.p7m");
    if (success != TRUE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCrypt2_Dispose(crypt);
        CkPem_Dispose(pem);
        CkCert_Dispose(certFromP12);
        return;
    }

    printf("Success.\n");


    CkCrypt2_Dispose(crypt);
    CkPem_Dispose(pem);
    CkCert_Dispose(certFromP12);

    }