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Go

Duplicate openssl pkcs12 –export –in certfile.cer –inkey certfile.key –out certfile.pfx

See more OpenSSL Examples

How to create a PKCS12 (.p12 or .pfx) from a certificate file and private key file: Demonstrates how to duplicate this OpenSSL command:
Duplicate openssl pkcs12 –export –in certfile.cer –inkey certfile.key –out certfile.pfx

Chilkat Go Downloads

Go
    success := false

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

    pkey := chilkat.NewPrivateKey()

    // Load the private key from the file.
    success = pkey.LoadAnyFormatFile("certFile.key","")
    if success != true {
        fmt.Println(pkey.LastErrorText())
        pkey.DisposePrivateKey()
        return
    }

    cert := chilkat.NewCert()
    // The LoadFromFile method auto-recognizes the format...
    success = cert.LoadFromFile("certfile.cer")
    if success != true {
        fmt.Println(cert.LastErrorText())
        pkey.DisposePrivateKey()
        cert.DisposeCert()
        return
    }

    // We'll need a cert chain object to create the PKCS12, so get it
    // from the cert.  
    // certChain is a CertChain
    certChain := cert.GetCertChain()
    if !cert.LastMethodSuccess() {
        fmt.Println(cert.LastErrorText())
        pkey.DisposePrivateKey()
        cert.DisposeCert()
        return
    }

    // Create the PFX object, add the cert and private key, and write to a .pfx file.
    pfx := chilkat.NewPfx()

    // The cert(s) are automatically added in the call to AddPrivateKey
    success = pfx.AddPrivateKey(pkey,certChain)
    if success != true {
        fmt.Println(pfx.LastErrorText())
        pkey.DisposePrivateKey()
        cert.DisposeCert()
        pfx.DisposePfx()
        return
    }

    // Write the .pfx to a file.
    password := "myPassword"
    success = pfx.ToFile(password,"certfile.pfx")
    if success != true {
        fmt.Println(pfx.LastErrorText())
        pkey.DisposePrivateKey()
        cert.DisposeCert()
        pfx.DisposePfx()
        return
    }

    fmt.Println("Success.")

    pkey.DisposePrivateKey()
    cert.DisposeCert()
    pfx.DisposePfx()