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Unicode C

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

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_LANGUAGE_ 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.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkCrypt2W.h>
#include <C_CkCertStoreW.h>
#include <C_CkJsonObjectW.h>
#include <C_CkCertW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkCrypt2W crypt;
    const wchar_t *signingCertSubject;
    const wchar_t *pfxFilename;
    const wchar_t *pfxPassword;
    HCkCertStoreW certStore;
    HCkJsonObjectW jsonCN;
    HCkCertW cert;
    const wchar_t *inFile;
    const wchar_t *outputFile;

    success = FALSE;

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

    crypt = CkCrypt2W_Create();

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

    certStore = CkCertStoreW_Create();
    success = CkCertStoreW_LoadPfxFile(certStore,pfxFilename,pfxPassword);
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertStoreW_lastErrorText(certStore));
        CkCrypt2W_Dispose(crypt);
        CkCertStoreW_Dispose(certStore);
        return;
    }

    jsonCN = CkJsonObjectW_Create();
    CkJsonObjectW_UpdateString(jsonCN,L"CN",signingCertSubject);

    cert = CkCertW_Create();
    success = CkCertStoreW_FindCert(certStore,jsonCN,cert);
    if (success == FALSE) {
        wprintf(L"Failed to find certificate by subject common name.\n");
        CkCrypt2W_Dispose(crypt);
        CkCertStoreW_Dispose(certStore);
        CkJsonObjectW_Dispose(jsonCN);
        CkCertW_Dispose(cert);
        return;
    }

    // Tell the crypt component to use this cert.
    success = CkCrypt2W_SetSigningCert(crypt,cert);

    // We can sign any type of file, creating a .p7m as output:
    inFile = L"/Users/chilkat/testData/pdf/sample.pdf";
    outputFile = L"/Users/chilkat/testData/p7m/sample.pdf.p7m";
    success = CkCrypt2W_CreateP7M(crypt,inFile,outputFile);
    if (success == FALSE) {
        wprintf(L"%s\n",CkCrypt2W_lastErrorText(crypt));
        CkCrypt2W_Dispose(crypt);
        CkCertStoreW_Dispose(certStore);
        CkJsonObjectW_Dispose(jsonCN);
        CkCertW_Dispose(cert);
        return;
    }

    // Verify and restore the original file:
    success = CkCrypt2W_SetVerifyCert(crypt,cert);

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

    success = CkCrypt2W_VerifyP7M(crypt,inFile,outputFile);
    if (success == FALSE) {
        wprintf(L"%s\n",CkCrypt2W_lastErrorText(crypt));
        CkCrypt2W_Dispose(crypt);
        CkCertStoreW_Dispose(certStore);
        CkJsonObjectW_Dispose(jsonCN);
        CkCertW_Dispose(cert);
        return;
    }

    wprintf(L"Success!\n");


    CkCrypt2W_Dispose(crypt);
    CkCertStoreW_Dispose(certStore);
    CkJsonObjectW_Dispose(jsonCN);
    CkCertW_Dispose(cert);

    }