/// <summary>
/// This method takes the required VAPID parameters and returns the required
/// header to be added to a Web Push Protocol Request.
/// </summary>
/// <param name="audience">This must be the origin of the push service.</param>
/// <param name="subject">This should be a URL or a 'mailto:' email address</param>
/// <param name="publicKey">The VAPID public key as a base64 encoded string</param>
/// <param name="privateKey">The VAPID private key as a base64 encoded string</param>
/// <param name="expiration">The expiration of the VAPID JWT.</param>
/// <returns>A dictionary of header key/value pairs.</returns>
public static Dictionary <string, string> GetVapidHeaders(string audience, string subject, string publicKey,
string privateKey, long expiration = -1)
{
ValidateAudience(audience);
ValidateSubject(subject);
ValidatePublicKey(publicKey);
ValidatePrivateKey(privateKey);
var decodedPrivateKey = UrlBase64.Decode(privateKey);
if (expiration == -1)
{
expiration = UnixTimeNow() + 43200;
}
else
{
ValidateExpiration(expiration);
}
var header = new Dictionary <string, object> {
{ "typ", "JWT" }, { "alg", "ES256" }
};
var jwtPayload = new Dictionary <string, object> {
{ "aud", audience }, { "exp", expiration }, { "sub", subject }
};
var signingKey = ECKeyHelper.GetPrivateKey(decodedPrivateKey);
var signer = new JwsSigner(signingKey);
var token = signer.GenerateSignature(header, jwtPayload);
var results = new Dictionary <string, string>
{
{ "Authorization", "WebPush " + token }, { "Crypto-Key", "p256ecdsa=" + publicKey }
};
return(results);
}
public void TestGenerateSignature()
{
var decodedPrivateKey = UrlBase64.Decode(TestPrivateKey);
var privateKey = ECKeyHelper.GetPrivateKey(decodedPrivateKey);
var header = new Dictionary <string, object>();
header.Add("typ", "JWT");
header.Add("alg", "ES256");
var jwtPayload = new Dictionary <string, object>();
jwtPayload.Add("aud", "aud");
jwtPayload.Add("exp", 1);
jwtPayload.Add("sub", "subject");
var signer = new JwsSigner(privateKey);
var token = signer.GenerateSignature(header, jwtPayload);
var tokenParts = token.Split('.');
Assert.AreEqual(3, tokenParts.Length);
var encodedHeader = tokenParts[0];
var encodedPayload = tokenParts[1];
var signature = tokenParts[2];
var decodedHeader = Encoding.UTF8.GetString(UrlBase64.Decode(encodedHeader));
var decodedPayload = Encoding.UTF8.GetString(UrlBase64.Decode(encodedPayload));
Assert.AreEqual(@"{""typ"":""JWT"",""alg"":""ES256""}", decodedHeader);
Assert.AreEqual(@"{""aud"":""aud"",""exp"":1,""sub"":""subject""}", decodedPayload);
var decodedSignature = UrlBase64.Decode(signature);
var decodedSignatureLength = decodedSignature.Length;
var isSignatureLengthValid = decodedSignatureLength == 66 || decodedSignatureLength == 64;
Assert.AreEqual(true, isSignatureLengthValid);
}
