C

Create CAdES p7m using AWS KMS to Sign in the Cloud

See more Signing in the Cloud Examples

Demonstrates how to create a CAdES p7m, using AWS KMS. The signing of the hash happens in the Cloud on AWS KMS. Everything else regarding the creation of CAdES happens locally within Chilkat.

Note: This example requires Chilkat v9.5.0.96 or greater.

C

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkCert cert;
    HCkJsonObject jsonAwsKms;
    HCkCrypt2 crypt;
    HCkJsonObject signedAttrs;
    const char *inputXmlPath;
    const char *outputP7mPath;

    success = FALSE;

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

    // Load the certificate used for signing.  The certificate's private key is stored in AWS KMS
    // However, we still need the certificate locally (without private key).
    cert = CkCert_Create();
    success = CkCert_LoadFromFile(cert,"qa_data/certs/myCert.cer");
    if (success == FALSE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkCert_Dispose(cert);
        return;
    }

    // Here's a screenshot showing the key ID of a private key in AWS KMS:
    // (image:https://example-code.com/images/aws_kms.jpg/endImage)

    // To sign using AWS KMS, 
    // add the following lines of code to specify your AWS authentication credentials,
    // and the ID of the KMS private key.
    jsonAwsKms = CkJsonObject_Create();
    // Set the "service" equal to "aws_kms" to tell Chilkat to use AWS KMS for signing.
    CkJsonObject_UpdateString(jsonAwsKms,"service","aws_kms");
    CkJsonObject_UpdateString(jsonAwsKms,"access_key","ACCESS_KEY");
    CkJsonObject_UpdateString(jsonAwsKms,"secret_key","SECRET_KEY");
    // Make sure to specify the correct region for your case.
    CkJsonObject_UpdateString(jsonAwsKms,"region","us-west-2");
    // In the above screenshot, our key ID is "187012e8-008f-4fc7-b100-5efe6146dff2".  You will use your key ID.
    CkJsonObject_UpdateString(jsonAwsKms,"key_id","187012e8-008f-4fc7-b100-5efe6146dff2");

    success = CkCert_SetCloudSigner(cert,jsonAwsKms);

    crypt = CkCrypt2_Create();

    success = CkCrypt2_SetSigningCert(crypt,cert);
    if (success == FALSE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCert_Dispose(cert);
        CkJsonObject_Dispose(jsonAwsKms);
        CkCrypt2_Dispose(crypt);
        return;
    }

    // The CadesEnabled property applies to all methods that create PKCS7 signatures. 
    // To create a CAdES-BES signature, set this property equal to true.
    CkCrypt2_putCadesEnabled(crypt,TRUE);

    CkCrypt2_putHashAlgorithm(crypt,"sha256");

    signedAttrs = CkJsonObject_Create();
    CkJsonObject_UpdateInt(signedAttrs,"contentType",1);
    CkJsonObject_UpdateInt(signedAttrs,"signingTime",1);
    CkJsonObject_UpdateInt(signedAttrs,"messageDigest",1);
    CkJsonObject_UpdateInt(signedAttrs,"signingCertificateV2",1);
    CkCrypt2_putSigningAttributes(crypt,CkJsonObject_emit(signedAttrs));

    // You can sign any type of file..
    inputXmlPath = "qa_data/e-Invoice.xml";
    outputP7mPath = "qa_output/signed.p7m";

    // Create the CAdES-BES attached signature, which contains the original data.
    // Chilkat will build the .p7m locally, but will (internally) use ARSS
    // to do the RSA signing remotely.
    success = CkCrypt2_CreateP7M(crypt,inputXmlPath,outputP7mPath);
    if (success == FALSE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCert_Dispose(cert);
        CkJsonObject_Dispose(jsonAwsKms);
        CkCrypt2_Dispose(crypt);
        CkJsonObject_Dispose(signedAttrs);
        return;
    }

    printf("Success.\n");


    CkCert_Dispose(cert);
    CkJsonObject_Dispose(jsonAwsKms);
    CkCrypt2_Dispose(crypt);
    CkJsonObject_Dispose(signedAttrs);

    }