Go

JWE using A256GCMKW

See more JSON Web Encryption (JWE) Examples

This example demonstrates creating a JCE with AES GCM key wrap. Go

    success := false

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

    plaintext := "My text to enrypt"

    jwe := chilkat.NewJwe()

    // First build the JWE Protected Header: 

    //         {
    //             "alg": "A256GCMKW",
    //             "kid": "18ec08e1-bfa9-4d95-b205-2b4dd1d4321d",
    //             "tag": "kfPduVQ3T3H6vnewt--ksw",
    //             "iv": "KkYT0GX_2jHlfqN_",
    //             "enc": "A128CBC-HS256"
    //         }

    jweProtHdr := chilkat.NewJsonObject()
    jweProtHdr.AppendString("alg","A256GCMKW")
    // kid is optional
    jweProtHdr.AppendString("kid","18ec08e1-bfa9-4d95-b205-2b4dd1d4321d")
    // tag is optional
    jweProtHdr.AppendString("tag","kfPduVQ3T3H6vnewt--ksw")
    jweProtHdr.AppendString("enc","A256GCM")
    // the iv should be 16 random chars.
    prng := chilkat.NewPrng()
    jweProtHdr.AppendString("iv",*prng.RandomString(16,true,true,true))
    jwe.SetProtectedHeader(jweProtHdr)

    fmt.Println("JWE Protected Header: ", *jweProtHdr.Emit())
    fmt.Println("--")

    // Given that we have 256-bit AES, our key should be 32 bytes.
    // The ascii string here is 32 bytes, therefore the 2nd arg is "ascii" to use these
    // ascii chars directly as the key.
    aesWrappingKey := "2baf4f730f5e4542b428593ef9cceb0e"
    jwe.SetWrappingKey(0,aesWrappingKey,"ascii")

    // Encrypt and return the JWE:
    strJwe := jwe.Encrypt(plaintext,"utf-8")
    if jwe.LastMethodSuccess() != true {
        fmt.Println(jwe.LastErrorText())
        jwe.DisposeJwe()
        jweProtHdr.DisposeJsonObject()
        prng.DisposePrng()
        return
    }

    // Show the JWE we just created:
    fmt.Println(*strJwe)

    // Decrypt the JWE that was just produced.
    // 1) Load the JWE.
    // 2) Set the AES wrapping key.
    // 3) Decrypt.
    jwe2 := chilkat.NewJwe()
    success = jwe2.LoadJwe(*strJwe)
    if success != true {
        fmt.Println(jwe2.LastErrorText())
        jwe.DisposeJwe()
        jweProtHdr.DisposeJsonObject()
        prng.DisposePrng()
        jwe2.DisposeJwe()
        return
    }

    // Set the AES wrap key.  Important to use "ascii"
    jwe2.SetWrappingKey(0,aesWrappingKey,"ascii")

    // Decrypt.
    originalPlaintext := jwe2.Decrypt(0,"utf-8")
    if jwe2.LastMethodSuccess() != true {
        fmt.Println(jwe2.LastErrorText())
        jwe.DisposeJwe()
        jweProtHdr.DisposeJsonObject()
        prng.DisposePrng()
        jwe2.DisposeJwe()
        return
    }

    fmt.Println("original text: ")
    fmt.Println(*originalPlaintext)

    jwe.DisposeJwe()
    jweProtHdr.DisposeJsonObject()
    prng.DisposePrng()
    jwe2.DisposeJwe()