/// <summary>
/// Gets the access token of an user that associate with a session and return a JSON Web Token
/// </summary>
/// <param name="userID">The string that presents the identity of the user</param>
/// <param name="sessionID">The string that presents the identity of the associated session</param>
/// <param name="roles">The collection that presents the roles that the user was belong to</param>
/// <param name="privileges">The collection that presents the access privileges that the user was got</param>
/// <param name="key">The key used to encrypt and sign</param>
/// <param name="onCompleted">The action to run to modify playload (if needed) when the processing is completed</param>
/// <param name="hashAlgorithm">The hash algorithm used to hash and sign (md5, sha1, sha256, sha384, sha512, ripemd/ripemd160, blake128, blake/blake256, blake384, blake512)</param>
/// <returns>A JSON Web Token that presents the access token</returns>
public static string GetAccessToken(string userID, string sessionID, IEnumerable <string> roles, IEnumerable <Privilege> privileges, BigInteger key, Action <JObject> onCompleted = null, string hashAlgorithm = "BLAKE256")
{
var token = new JObject
{
{ "jti", sessionID },
{ "uid", userID },
{ "rls", (roles ?? new List <string>()).Distinct(StringComparer.OrdinalIgnoreCase).ToJArray() },
{ "pls", (privileges ?? new List <Privilege>()).ToJArray() }
}.ToString(Formatting.None);
var hash = token.GetHash(hashAlgorithm);
var signature = key.Sign(hash);
var publicKey = key.GenerateECCPublicKey();
var payload = new JObject
{
{ "iat", DateTime.Now.ToUnixTimestamp() },
{ "exp", DateTime.Now.AddDays(90).ToUnixTimestamp() },
{ "nbf", DateTime.Now.AddDays(-30).ToUnixTimestamp() },
{ "jti", publicKey.Encrypt(sessionID.HexToBytes()).ToHex() },
{ "uid", userID },
{ "atk", publicKey.Encrypt(token, true) },
{ "ath", hash.ToHex() },
{ "sig", ECCsecp256k1.GetSignature(signature) }
};
onCompleted?.Invoke(payload);
return(JSONWebToken.Encode(payload, ECCsecp256k1.GetPublicKey(publicKey).ToHex(), hashAlgorithm));
}
/// <summary>
/// Parses the given access token and return an <see cref="User">User</see> object
/// </summary>
/// <param name="accessToken">The JSON Web Token that presents the access token</param>
/// <param name="key">The key used to decrypt and verify</param>
/// <param name="onCompleted">The action to run to update user information (if needed) when the processing is completed</param>
/// <param name="hashAlgorithm">The hash algorithm used to hash and sign (md5, sha1, sha256, sha384, sha512, ripemd/ripemd160, blake128, blake/blake256, blake384, blake512)</param>
/// <returns>The <see cref="User">User</see> object that presented by the access token</returns>
public static User ParseAccessToken(this string accessToken, BigInteger key, Action <JObject, User> onCompleted = null, string hashAlgorithm = "BLAKE256")
{
try
{
// decode JSON Web Token
var publicKey = key.GenerateECCPublicKey();
var payload = JSONWebToken.DecodeAsJson(accessToken, ECCsecp256k1.GetPublicKey(publicKey).ToHex());
var token = payload.ToExpandoObject();
// times
var issuedAt = token.Get <long>("iat").FromUnixTimestamp();
var expiresAt = token.Get <long>("exp").FromUnixTimestamp();
var notBefore = token.Get <long>("nbf").FromUnixTimestamp();
if (DateTime.Now > expiresAt || DateTime.Now < notBefore || issuedAt > expiresAt || issuedAt < notBefore)
{
throw new TokenExpiredException();
}
// identities
var tokenID = token.Get <string>("jti");
var userID = token.Get <string>("uid");
if (string.IsNullOrWhiteSpace(tokenID) || string.IsNullOrWhiteSpace(userID))
{
throw new InvalidTokenException("Invalid identity");
}
else
{
tokenID = key.Decrypt(tokenID.HexToBytes()).ToHex();
}
// signature
var hash = token.Get <string>("ath").HexToBytes();
var signature = ECCsecp256k1.GetSignature(token.Get <string>("sig"));
if (!publicKey.Verify(hash, signature))
{
throw new InvalidTokenSignatureException();
}
accessToken = key.Decrypt(token.Get <string>("atk"), true);
if (!hash.SequenceEqual(accessToken.GetHash(hashAlgorithm)))
{
throw new InvalidTokenException("Not matched");
}
// info of access token
token = accessToken.ToExpandoObject();
if (!userID.IsEquals(token.Get <string>("uid")) || !tokenID.IsEquals(token.Get <string>("jti")))
{
throw new InvalidTokenException("Invalid identity");
}
var roles = token.Get <List <string> >("rls");
var privileges = token.Get <List <Privilege> >("pls");
// create new user identity
var user = new User(userID, tokenID, roles, privileges);
// callback
onCompleted?.Invoke(payload, user);
// return user identity
return(user);
}
catch (Exception ex)
{
if (ex is TokenExpiredException || ex is InvalidTokenSignatureException || ex is InvalidTokenException)
{
throw;
}
throw new InvalidTokenException("Invalid access token", ex);
}
}
