Unicode C

Convert Let's Encrypt PEM Files to a PFX

See more PFX/P12 Examples

Demonstrates how to convert the .pem files provided by Let's Encrypt to a single PFX. Unicode C

#include <C_CkStringBuilderW.h>
#include <C_CkPfxW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkStringBuilderW sbPem;
    HCkStringBuilderW sbFullChainPem;
    HCkPfxW pfx;
    const wchar_t *pfxPassword;

    success = FALSE;

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

    // Let's Encrypt provides four .pem files
    // 1. fullchain.pem
    // 2. privkey.pem
    // 3. cert.pem
    // 4. chain.pem

    // The cert.pem and chain.pem are redundant. 
    // The fullchain.pem is composed of the cert.pem and chain.pem.

    // To convert the PEM's to a single .pfx, we don't need the redundant data.
    // The privkey.pem and fullchain.pem provide the required data.
    // We can ignore cert.pem and chain.pem (because those certs are already found in fullchain.pem).

    // We need a single .pem file that contains both the private key, the cert,
    // and the certs in the chain of authentication.
    // Let's combine priveky.pem and fullchain.pem into a single .pem

    sbPem = CkStringBuilderW_Create();
    success = CkStringBuilderW_LoadFile(sbPem,L"qa_data/pem/lets_encrypt/privkey.pem",L"utf-8");
    if (success == FALSE) {
        wprintf(L"Failed to load privkey.pem\n");
        CkStringBuilderW_Dispose(sbPem);
        return;
    }

    // To be safe, append a blank line..
    CkStringBuilderW_AppendLine(sbPem,L"",FALSE);

    sbFullChainPem = CkStringBuilderW_Create();
    success = CkStringBuilderW_LoadFile(sbFullChainPem,L"qa_data/pem/lets_encrypt/fullchain.pem",L"utf-8");
    if (success == FALSE) {
        wprintf(L"Failed to load fullchain.pem\n");
        CkStringBuilderW_Dispose(sbPem);
        CkStringBuilderW_Dispose(sbFullChainPem);
        return;
    }

    // Append the full cert chain PEM to the private key PEM.
    CkStringBuilderW_AppendSb(sbPem,sbFullChainPem);

    // Load the combined PEM into a Chilkat PFX object.
    pfx = CkPfxW_Create();
    success = CkPfxW_LoadPem(pfx,CkStringBuilderW_getAsString(sbPem),L"no password required");
    if (success == FALSE) {
        wprintf(L"%s\n",CkPfxW_lastErrorText(pfx));
        CkStringBuilderW_Dispose(sbPem);
        CkStringBuilderW_Dispose(sbFullChainPem);
        CkPfxW_Dispose(pfx);
        return;
    }

    // Write the PFX w/ a password.
    pfxPassword = L"secret";
    success = CkPfxW_ToFile(pfx,pfxPassword,L"qa_output/sample.pfx");
    if (success == FALSE) {
        wprintf(L"%s\n",CkPfxW_lastErrorText(pfx));
        CkStringBuilderW_Dispose(sbPem);
        CkStringBuilderW_Dispose(sbFullChainPem);
        CkPfxW_Dispose(pfx);
        return;
    }

    wprintf(L"Success!\n");


    CkStringBuilderW_Dispose(sbPem);
    CkStringBuilderW_Dispose(sbFullChainPem);
    CkPfxW_Dispose(pfx);

    }