JwtInspector.Core
1.1.0
dotnet add package JwtInspector.Core --version 1.1.0
NuGet\Install-Package JwtInspector.Core -Version 1.1.0
<PackageReference Include="JwtInspector.Core" Version="1.1.0" />
<PackageVersion Include="JwtInspector.Core" Version="1.1.0" />
<PackageReference Include="JwtInspector.Core" />
paket add JwtInspector.Core --version 1.1.0
#r "nuget: JwtInspector.Core, 1.1.0"
#addin nuget:?package=JwtInspector.Core&version=1.1.0
#tool nuget:?package=JwtInspector.Core&version=1.1.0
JwtInspector - A Library for Decoding and Validating JWT Tokens
JwtInspector is a C# library that provides utilities for decoding, validating, and inspecting JWT (JSON Web Tokens). This library simplifies working with JWTs by providing easy-to-use methods for extracting data, validating tokens, and more.
The library supports various use cases, such as decoding JWT payloads, validating token expiration, and verifying the authenticity of tokens using HMAC-SHA algorithms.
Features
- Decode JWT tokens to extract claims and payload.
- Validate JWT token authenticity and expiration.
- Support for handling
iat
(issued at),exp
(expiration), andsub
(subject) claims. - Provides a simple interface for inspecting JWT headers, payloads, and signatures.
- Easy-to-use methods for handling base64 URL encoding and decoding.
- JWT validation against a symmetric key (HMAC-SHA256) and token verification.
Installation
You can install the library via the NuGet package manager with the following command:
dotnet add package JwtInspector.Core
Usage
Decoding JWT Payload
To decode the payload of a JWT token and get a dictionary of claims:
using JwtInspector.Core.Services;
var jwtInspector = new JwtInspectorService();
string token = "<your-jwt-token>";
var claims = jwtInspector.DecodePayloadAsJson(token);
Console.WriteLine(claims);
Validating JWT Token
To validate a JWT token using a secret key:
using JwtInspector.Core.Services;
var jwtInspector = new JwtInspectorService();
string token = "<your-jwt-token>";
string secretKey = "<your-secret-key>";
bool isValid = jwtInspector.ValidateToken(token, secretKey);
Console.WriteLine($"Token valid: {isValid}");
Extracting JWT Parts
You can extract the header, payload, and signature from a JWT token:
using JwtInspector.Core.Services;
var jwtInspector = new JwtInspectorService();
string token = "<your-jwt-token>";
var (header, payload, signature) = jwtInspector.ExtractJwtParts(token);
Console.WriteLine($"Header: {header}");
Console.WriteLine($"Payload: {payload}");
Console.WriteLine($"Signature: {signature}");
Checking Token Expiration
To check if a JWT token is expired:
using JwtInspector.Core.Services;
var jwtInspector = new JwtInspectorService();
string token = "<your-jwt-token>";
bool isExpired = jwtInspector.IsExpired(token);
Console.WriteLine($"Token expired: {isExpired}");
Extracting JWT Claims
To get the claims from a JWT token:
using JwtInspector.Core.Services;
var jwtInspector = new JwtInspectorService();
string token = "<your-jwt-token>";
var claims = jwtInspector.GetClaims(token);
foreach (var claim in claims)
{
Console.WriteLine($"{claim.Key}: {claim.Value}");
}
Example Usage: Validating a Token with HMAC-SHA256
using JwtInspector.Core.Services;
using Microsoft.IdentityModel.Tokens;
var jwtInspector = new JwtInspectorService();
string secretKey = "my_secret_key_123456789123456789"; // 32 bytes key
string token = "<your-jwt-token>";
bool isValid = jwtInspector.ValidateToken(token, secretKey);
Console.WriteLine($"Is token valid: {isValid}");
Methods Overview
Decoding methods
DecodeBase64Url(string input)
: Decodes a Base64Url encoded string.DecodePayload(string token)
: Decodes the payload of a JWT token.DecodePayloadAsJson(string token)
: Returns the decoded JWT payload as a JSON string.ExtractJwtParts(string token)
: Extracts the header, payload, and signature from a JWT token.GetAudience(string token)
: Extracts the audience (aud
) from the JWT token.GetClaims(string token)
: Extracts all claims from the JWT token.GetExpirationDate(string token)
: Extracts the expiration date (exp
) of the JWT token.GetIssuedAt(string token)
: Extracts the issued date (iat
) of the JWT token.GetJwtId(string token)
: Extracts the JWT ID (jti
) of the JWT token.GetSigningAlgorithm(string token)
: Extracts the signing algorithm used in the JWT.IsExpired(string token)
: Checks if the JWT token is expired.IsValidFormat(string token)
: Checks if the JWT token has a valid format (three parts separated by dots).
Validation methods
ValidateToken(string token, string secretKey)
: Validates the JWT token using the provided secret key for HMAC-SHA256 verification.VerifyIssuer(string token, string expectedIssuer)
: Verifies that the issuer of the token matches the expected issuer.ValidateIssuerAndAudience(string token, string expectedIssuer, string expectedAudience)
: Verifies that the issuer and audience of the token match the expected values.ValidateLifetime(string token)
: Validates the token's lifetime based on the expiration date.ValidateAlgorithm(string token, string expectedAlgorithm)
: Verifies that the algorithm used to sign the token matches the expected algorithm.
JWT Format
A valid JWT token consists of three parts:
- Header: Contains metadata such as the signing algorithm (
alg
) and token type (typ
). - Payload: Contains the claims, which can be public, private, or registered claims such as
sub
,iat
,exp
,aud
. - Signature: A cryptographic signature used to verify the integrity of the token.
A JWT token is typically represented in the following format: header.payload.signature
Example JWT
A typical JWT might look like this:
eyJhbGciOiAiSFMyNTYiLCAidHlwIjogIkpXVCJ9.eyJzdWIiOiAiMTIzNDU2Nzg5MCIsICJuYW1lIjogIkpvaG4gRG9lIiwgImlhdCI6IDE1MTYyMzkwMjJ9.MD8fpgF7N0XWhQGGVm9lA_EvVoHkcmrr74xhL2y7H3U
Contributing
Thank you for considering to help out with the source code! If you'd like to contribute, please fork, fix, commit and send a pull request for the maintainers to review and merge into the main code base.
- Setting up Git
- Fork the repository
- Open an issue if you encounter a bug or have a suggestion for improvements/features
Licensee
JwtInspector source code is available under MIT License, see license in the source.
Contact
Please contact at francesco.delre.87[at]gmail.com for any details.
Product | Versions Compatible and additional computed target framework versions. |
---|---|
.NET | net8.0 is compatible. net8.0-android was computed. net8.0-browser was computed. net8.0-ios was computed. net8.0-maccatalyst was computed. net8.0-macos was computed. net8.0-tvos was computed. net8.0-windows was computed. net9.0 was computed. net9.0-android was computed. net9.0-browser was computed. net9.0-ios was computed. net9.0-maccatalyst was computed. net9.0-macos was computed. net9.0-tvos was computed. net9.0-windows was computed. net10.0 was computed. net10.0-android was computed. net10.0-browser was computed. net10.0-ios was computed. net10.0-maccatalyst was computed. net10.0-macos was computed. net10.0-tvos was computed. net10.0-windows was computed. |
-
net8.0
- System.IdentityModel.Tokens.Jwt (>= 8.2.1)
NuGet packages
This package is not used by any NuGet packages.
GitHub repositories
This package is not used by any popular GitHub repositories.