(C) Sign a File to Create a .p7m File (using a PFX)

C example to sign a file creating a .p7m file as output. The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

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#include <C_CkCrypt2.h>
#include <C_CkCertStore.h>
#include <C_CkCert.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    const char *signingCertSubject;
    const char *pfxFilename;
    const char *pfxPassword;
    HCkCertStore certStore;
    BOOL success;
    HCkCert cert;
    const char *inFile;
    const char *outputFile;

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

    crypt = CkCrypt2_Create();

    // Use a digital certificate and private key from a PFX file (.pfx or .p12).
    signingCertSubject = "Acme Inc";
    pfxFilename = "/Users/chilkat/testData/pfx/acme.pfx";
    pfxPassword = "test123";

    certStore = CkCertStore_Create();
    success = CkCertStore_LoadPfxFile(certStore,pfxFilename,pfxPassword);
    if (success != TRUE) {
        printf("%s\n",CkCertStore_lastErrorText(certStore));
        CkCrypt2_Dispose(crypt);
        CkCertStore_Dispose(certStore);
        return;
    }

    cert = CkCertStore_FindCertBySubjectCN(certStore,signingCertSubject);
    if (CkCertStore_getLastMethodSuccess(certStore) == FALSE) {
        printf("Failed to find certificate by subject common name.\n");
        CkCrypt2_Dispose(crypt);
        CkCertStore_Dispose(certStore);
        return;
    }

    // Tell the crypt component to use this cert.
    success = CkCrypt2_SetSigningCert(crypt,cert);

    // We can sign any type of file, creating a .p7m as output:
    inFile = "/Users/chilkat/testData/pdf/sample.pdf";
    outputFile = "/Users/chilkat/testData/p7m/sample.pdf.p7m";
    success = CkCrypt2_CreateP7M(crypt,inFile,outputFile);
    if (success == FALSE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCert_Dispose(cert);
        CkCrypt2_Dispose(crypt);
        CkCertStore_Dispose(certStore);
        return;
    }

    // Verify and restore the original file:
    success = CkCrypt2_SetVerifyCert(crypt,cert);

    inFile = outputFile;
    outputFile = "/Users/chilkat/testData/pdf/restored.pdf";

    success = CkCrypt2_VerifyP7M(crypt,inFile,outputFile);
    if (success == FALSE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCert_Dispose(cert);
        CkCrypt2_Dispose(crypt);
        CkCertStore_Dispose(certStore);
        return;
    }

    CkCert_Dispose(cert);

    printf("Success!\n");


    CkCrypt2_Dispose(crypt);
    CkCertStore_Dispose(certStore);

    }