public KRB_TGS_REP TGS(KRB_TGS_REQ req)
{
// Invent key K_AB
Key k_ab = new Key(7);
k_ab.CreateRandomKey();
// Decrypt TGT to get SA
Key sa = req.Tgt.GetKS_A(this.k_kdc);
// Decrypt authenticator
DateTime timestamp = req.Authenticator.GetTimestamp(sa);
// Verifies timestamp
DateTime now = DateTime.Now;
int diffTimestamp = now.Second - timestamp.Second;
if (diffTimestamp > this.maxTimestamp)
{
// Fail in the timestamp
return null;
}
// Finds Bob's master key KB
Key k_b = GetUserKey(req.ReqUser);
// Ticket to Bob = K_B[Alice, K_AB]
Ticket ticket = new Ticket(k_b, req.Tgt.GetUser(this.k_kdc), k_ab);
return new KRB_TGS_REP(sa, req.ReqUser, k_ab, ticket);
}
public static void Main(string[] args)
{
// I have to check the args
string userName = args[0];
string userRemo = args[1];
Key aliceKey = new Key("ABCDEFGH");
#region Throw our server
string confFile = Application.ExecutablePath + "." + userName.ToLower() + ".config";
Console.WriteLine(confFile);
RemotingConfiguration.Configure(confFile , false);
#endregion
#region Connection with server
System.Configuration.AppSettingsReader configurationAppSettings =
new System.Configuration.AppSettingsReader();
//String url = (string)ConfigurationSettings.AppSettings["RemotingUrl"];
String url =
IKdc kdc = (IKdc)Activator.GetObject(typeof(ShareClasses.IKdc), url);
#endregion
#region AS_REQ
User alice = new User(userName);
KRB_AS_REQ asReq = new KRB_AS_REQ(alice);
KRB_AS_REP asRep = kdc.AS(asReq);
#endregion
#region TGS_REQ
User bob = new User(userRemo);
Authenticator auth = new Authenticator(aliceKey);
KRB_TGS_REQ tgsReq = new KRB_TGS_REQ(asRep.GetTGT(aliceKey), auth, bob);
KRB_TGS_REP tgsRep = kdc.TGS(tgsReq);
#endregion
#region AP_REQ
Ticket ticket = tgsRep.GetTicket(aliceKey);
string bobUrl = (string)ConfigurationSettings.AppSettings["RemotingUser"];
Server bobServer = (Server)Activator.GetObject(typeof(Workstation.Server), bobUrl);
KRB_AP_REQ apReq = new KRB_AP_REQ(ticket, auth);
KRB_AP_REP apRep = bobServer.AP(apReq);
#endregion
}
