public static async Task OnClientAuthenticationSession(PacketHandlerContext c)
{
var request = CMSG_AUTH_SESSION.Read(c.Packet);
var build = (int)request.Build;
if (c.Client.Build != build)
{
c.Client.Log($"Expected build {c.Client.Build} but is {build}.", LogLevel.Warning);
c.Client.Build = build;
}
var session = c.AccountService.GetSession(request.Identifier);
if (session is null)
{
// return [SMSG_AUTH_RESPONSE, 21]
throw new ArgumentException($"No user with name {request.Identifier} found in db.");
}
////: if server is full and NOT GM return [SMSG_AUTH_RESPONSE, 21]
////: if player is already connected return [SMSG_AUTH_RESPONSE, 13]
using var sha = new SHA1CryptoServiceProvider();
var calculatedDigest = sha.ComputeHash(
Encoding.ASCII.GetBytes(request.Identifier)
.Concat(new byte[] { 0, 0, 0, 0 })
.Concat(BitConverter.GetBytes(request.Seed))
.Concat(SMSG_AUTH_CHALLENGE.AuthSeed)
.Concat(session.SessionKey)
.ToArray());
if (!calculatedDigest.SequenceEqual(request.Digest))
{
//return [SMSG_AUTH_RESPONSE, 21]
throw new InvalidOperationException("Wrong digest SMSG_AUTH_RESPONSE");
}
c.Client.HeaderCrypt = HeaderCryptFactory.Create(session.SessionKey, build);
c.Client.Identifier = request.Identifier;
await c.Client.SendPacket(new SMSG_AUTH_RESPONSE(build));
}
