This library supports generating and decoding JSON Web Tokens.
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- .NET Framework 3.5 and higher versions
- .NET Framework 4.0 and higher versions
- .NET Standard 1.3
- .NET Standard 2.0
The following projects and their resulting packages are licensed under Public Domain, see the LICENSE#Public-Domain file.
- JWT
The following projects and their resulting packages are licensed under the MIT License, see the LICENSE#MIT file.
- JWT.Extensions.AspNetCore
- JWT.Extensions.Owin
var payload = new Dictionary<string, object>
{
{ "claim1", 0 },
{ "claim2", "claim2-value" }
};
const string secret = "GQDstcKsx0NHjPOuXOYg5MbeJ1XT0uFiwDVvVBrk";
IJwtAlgorithm algorithm = new HMACSHA256Algorithm(); // symmetric
IJsonSerializer serializer = new JsonNetSerializer();
IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
IJwtEncoder encoder = new JwtEncoder(algorithm, serializer, urlEncoder);
var token = encoder.Encode(payload, secret);
Console.WriteLine(token); var token = new JwtBuilder()
.WithAlgorithm(new HMACSHA256Algorithm()) // symmetric
.WithSecret(secret)
.AddClaim("exp", DateTimeOffset.UtcNow.AddHours(1).ToUnixTimeSeconds())
.AddClaim("claim2", "claim2-value")
.Encode();
Console.WriteLine(token);The output would be:
eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJjbGFpbTEiOjAsImNsYWltMiI6ImNsYWltMi12YWx1ZSJ9.8pwBI_HtXqI3UgQHQ_rDRnSQRxFL1SR8fbQoS-5kM5s
const string token = "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJjbGFpbTEiOjAsImNsYWltMiI6ImNsYWltMi12YWx1ZSJ9.8pwBI_HtXqI3UgQHQ_rDRnSQRxFL1SR8fbQoS-5kM5s";
const string secret = "GQDstcKsx0NHjPOuXOYg5MbeJ1XT0uFiwDVvVBrk";
try
{
IJsonSerializer serializer = new JsonNetSerializer();
var provider = new UtcDateTimeProvider();
IJwtValidator validator = new JwtValidator(serializer, provider);
IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
IJwtAlgorithm algorithm = new HMACSHA256Algorithm(); // symmetric
IJwtDecoder decoder = new JwtDecoder(serializer, validator, urlEncoder, algorithm);
var json = decoder.Decode(token, secret, verify: true);
Console.WriteLine(json);
}
catch (TokenExpiredException)
{
Console.WriteLine("Token has expired");
}
catch (SignatureVerificationException)
{
Console.WriteLine("Token has invalid signature");
}var json = new JwtBuilder()
.WithAlgorithm(new HMACSHA256Algorithm()) // symmetric
.WithSecret(secret)
.MustVerifySignature()
.Decode(token);
Console.WriteLine(json);or
var json = new JwtBuilder()
.WithAlgorithm(new RS256Algorithm(certificate)) // asymmetric
.MustVerifySignature()
.Decode(token);
Console.WriteLine(json);The output would be:
{ "claim1": 0, "claim2": "claim2-value" }
You can also deserialize the JSON payload directly to a .NET type:
var payload = decoder.DecodeToObject<IDictionary<string, object>>(token, secret);
Console.WriteLine(payload["claim2"]);var payload = new JwtBuilder()
.WithAlgorithm(new HMACSHA256Algorithm()) // symmetric
.WithSecret(secret)
.MustVerifySignature()
.Decode<IDictionary<string, object>>(token);
Console.WriteLine(payload["claim2"]);and
var payload = new JwtBuilder()
.WithAlgorithm(new RS256Algorithm(certificate)) // asymmetric
.MustVerifySignature()
.Decode<IDictionary<string, object>>(token);
Console.WriteLine(payload["claim2"]);The output would be:
claim2-value
As described in the JWT RFC, the exp "claim identifies the expiration time on or after which the JWT MUST NOT be accepted for processing." If an exp claim is present and is prior to the current time the token will fail verification. The exp (expiry) value must be specified as the number of seconds since 1/1/1970 UTC.
var provider = new UtcDateTimeProvider();
var now = provider.GetNow();
var secondsSinceEpoch = UnixEpoch.GetSecondsSince(now);
var payload = new Dictionary<string, object>
{
{ "exp", secondsSinceEpoch }
};
const string secret = "GQDstcKsx0NHjPOuXOYg5MbeJ1XT0uFiwDVvVBrk";
var token = encoder.Encode(payload, secret);
var json = decoder.Decode(token, secret); // throws TokenExpiredExceptionvar serializer = new JsonNetSerializer();
var urlEncoder = new JwtBase64UrlEncoder();
var decoder = new JwtDecoder(serializer, urlEncoder);
JwtHeader header = decoder.DecodeHeader<JwtHeader>(token);
var typ = header.Type; // JWT
var alg = header.Algorithm; // RS256
var kid = header.KeyId; // CFAEAE2D650A6CA9862575DE54371EA980643849var builder = new JwtBuilder();
JwtHeader header = builder.DecodeHeader<JwtHeader>(TestData.TokenByAsymmetricAlgorithm);
var typ = header.Type; // JWT
var alg = header.Algorithm; // RS256
var kid = header.KeyId; // CFAEAE2D650A6CA9862575DE54371EA980643849By default JSON serialization is performed by JsonNetSerializer implemented using Json.Net. To use a different one, implement the IJsonSerializer interface:
public class CustomJsonSerializer : IJsonSerializer
{
public string Serialize(object obj)
{
// Implement using favorite JSON serializer
}
public T Deserialize<T>(string json)
{
// Implement using favorite JSON serializer
}
}And then pass this serializer to JwtEncoder constructor:
IJwtAlgorithm algorithm = new HMACSHA256Algorithm(); // symmetric
IJsonSerializer serializer = new CustomJsonSerializer();
IBase64UrlEncoder urlEncoder = new JwtBase64UrlEncoder();
IJwtEncoder encoder = new JwtEncoder(algorithm, serializer, urlEncoder);As mentioned above, the default JSON serialization is done by JsonNetSerializer. You can define your own custom serialization settings as follows:
JsonSerializer customJsonSerializer = new JsonSerializer
{
// All keys start with lowercase characters instead of the exact casing of the model/property, e.g. fullName
ContractResolver = new CamelCasePropertyNamesContractResolver(),
// Nice and easy to read, but you can also use Formatting.None to reduce the payload size
Formatting = Formatting.Indented,
// The most appropriate datetime format.
DateFormatHandling = DateFormatHandling.IsoDateFormat,
// Don't add keys/values when the value is null.
NullValueHandling = NullValueHandling.Ignore,
// Use the enum string value, not the implicit int value, e.g. "red" for enum Color { Red }
Converters.Add(new StringEnumConverter())
};
IJsonSerializer serializer = new JsonNetSerializer(customJsonSerializer);
public void ConfigureServices(IServiceCollection services)
{
services.AddAuthentication(options =>
{
options.DefaultAuthenticateScheme = JwtAuthenticationDefaults.AuthenticationScheme;
options.DefaultChallengeScheme = JwtAuthenticationDefaults.AuthenticationScheme;
})
.AddJwt(options =>
{
// secrets
options.Keys = new[] { "GQDstcKsx0NHjPOuXOYg5MbeJ1XT0uFiwDVvVBrk" };
// force JwtDecoder to throw exception if JWT signature is invalid
options.VerifySignature = true;
});
}
public void Configure(IApplicationBuilder app)
{
app.UseAuthentication();
}options.IdentityFactory = dic => new ClaimsIdentity(
dic.Select(p => new Claim(p.Key, p.Value)));
options.TicketFactory = (identity, scheme) => new AuthenticationTicket(
new ClaimsPrincipal(identity),
new AuthenticationProperties(),
scheme.Name);app.UseJwtMiddleware();Note: work in progress as the scenario/usage is not designed yet. The registered will do nothing but throw an exception.
app.UseJwtMiddleware();Note: work in progress as the scenario/usage is not designed yet. The registered will do nothing but throw an exception.