(C) Create PKCS7 Signed File (.p7m)

Demonstrates how to sign a file to create a .p7m that contains both the file contents and the signature.

Note: This example requires Chilkat v10.1.2 or greater.

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

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    HCkCertStore certStore;
    BOOL success;
    HCkJsonObject jsonCN;
    HCkCert cert;
    const char *inFile;
    const char *outFile;

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

    crypt = CkCrypt2_Create();

    certStore = CkCertStore_Create();

    // Load a PFX file into a certificate store object.
    success = CkCertStore_LoadPfxFile(certStore,"myPfx.pfx","pfxPassword");
    if (success != TRUE) {
        printf("%s\n",CkCertStore_lastErrorText(certStore));
        CkCrypt2_Dispose(crypt);
        CkCertStore_Dispose(certStore);
        return;
    }

    // Get the certificate by subject common name.
    // This should be the cert within the PFX that also
    // has a private key (also stored within the PFX).
    jsonCN = CkJsonObject_Create();
    CkJsonObject_UpdateString(jsonCN,"CN","myCert");
    cert = CkCert_Create();
    success = CkCertStore_FindCert(certStore,jsonCN,cert);
    if (success == FALSE) {
        printf("%s\n",CkCertStore_lastErrorText(certStore));
        CkCrypt2_Dispose(crypt);
        CkCertStore_Dispose(certStore);
        CkJsonObject_Dispose(jsonCN);
        CkCert_Dispose(cert);
        return;
    }

    // Tell the crypt object to use the certificate for signing:
    success = CkCrypt2_SetSigningCert(crypt,cert);

    // Sign a file, producing a .p7m as output.
    // The input file is unchanged, the test.p7m contains the 
    // contents of the input file and the signature.
    inFile = "test.txt";
    outFile = "testp7m";
    success = CkCrypt2_CreateP7M(crypt,inFile,outFile);
    if (success != TRUE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCrypt2_Dispose(crypt);
        CkCertStore_Dispose(certStore);
        CkJsonObject_Dispose(jsonCN);
        CkCert_Dispose(cert);
        return;
    }

    printf("Success!\n");


    CkCrypt2_Dispose(crypt);
    CkCertStore_Dispose(certStore);
    CkJsonObject_Dispose(jsonCN);
    CkCert_Dispose(cert);

    }