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Go

Yubikey RSA Encrypt/Decrypt

See more RSA Examples

Demonstrates how to do RSA decryption using a private key stored on a Yubikey (or other USB token or smartcard).

Note: RSA encryption uses the public key, which is freely exportable and does not need to occur on the token/smartcard.

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Go
    success := false

    // This example assumes you have a certificate with private key on the Yubikey token.
    // When doing simple RSA encryption/decryption, we don't actually need the certificate,
    // but we'll be using the private key associated with the certificate.
    // 
    // The sensitive/secret material that needs to be kept private is the private key.
    // The certificate itself and the public key can be freely shared.
    // 

    // We're going to encrypt and decrypt 32-bytes of data.
    bd := chilkat.NewBinData()
    success = bd.AppendEncoded("000102030405060708090A0B0C0D0E0F","hex")
    success = bd.AppendEncoded("000102030405060708090A0B0C0D0E0F","hex")

    // Let's get the desired cert.
    // For this example, a self-signed certificate with a 2048-bit RSA key was generated in slot 9A.
    cert := chilkat.NewCert()

    // Force Chilkat to use PKCS11 over ScMinidriver (if on Windows) and Apple Keychain (if on MacOS)
    cert.SetUncommonOptions("NoScMinidriver,NoAppleKeychain")

    cert.SetSmartCardPin("123456")

    success = cert.LoadFromSmartcard("cn=chilkat_test_2048")
    if success == false {
        fmt.Println(cert.LastErrorText())
        bd.DisposeBinData()
        cert.DisposeCert()
        return
    }

    // RSA encrypt using the public key.
    rsa := chilkat.NewRsa()

    // Provide the RSA object with the certificate on the Yubkey.
    success = rsa.SetX509Cert(cert,true)
    if success == false {
        fmt.Println(rsa.LastErrorText())
        bd.DisposeBinData()
        cert.DisposeCert()
        rsa.DisposeRsa()
        return
    }

    // RSA encrypt using the public key.
    usePrivateKey := false
    success = rsa.EncryptBd(bd,usePrivateKey)
    if success == false {
        fmt.Println(rsa.LastErrorText())
        bd.DisposeBinData()
        cert.DisposeCert()
        rsa.DisposeRsa()
        return
    }

    fmt.Println("RSA Encrypted Output in Hex:")
    fmt.Println(*bd.GetEncoded("hex"))

    // Now let's decrypt, using the private key on the Yubikey.
    usePrivateKey = true
    success = rsa.DecryptBd(bd,usePrivateKey)
    if success == false {
        fmt.Println(rsa.LastErrorText())
        bd.DisposeBinData()
        cert.DisposeCert()
        rsa.DisposeRsa()
        return
    }

    fmt.Println("RSA Decrypted Output in Hex:")
    fmt.Println(*bd.GetEncoded("hex"))

    bd.DisposeBinData()
    cert.DisposeCert()
    rsa.DisposeRsa()