ModernUO/Projects/UOContent/Accounting/AccountHandler.cs
Kamron Batman 4cd668ef61
feat: Moves TcpServer to another thread. Rewrites Firewall (#1660)
## Breaking Changes
* The Firewall and IP Limiter have been rewritten. Please read the notes carefully!
* `TcpServer.Instances` moved back to `NetState.Instances` - sorry - it was stupid to move it to begin with.

> [!Note]
> Sockets that fail the IP Limiter or Firewall will be immediately and forcibly disconnected.
> This means they will be stuck at "Verifying account..." if it was a real client.

### Summary
- Removes firewall wildcard support.
- Removes `AccessRestrictions`.
- Moves Firewall/IPLimiter to the core.
- Moves `TcpServer` to its own thread.
- Removes the `SocketConnect` and `SocketDisconnect` event sinks.
- Moves `Instances` back to `NetState.Instances`.
- Fixes a long standing bug with bad handling of duplicate listener addresses.

#### Firewall
The firewall has been completely rewritten. There is now an "Admin Firewall" which saves to the config file. Secondarily, there is an internal firewall used exclusively by the TcpServer while processing sockets. The Admin firewall mirrors it's additions/deletions to the internal firewall by adding requests to a queue.

> [!IMPORTANT]  
> **Wildcard firewall entries, such as `X`, `*`, `?` are not allowed.**
> **Ranges in between IP classes or sextets are not allowed.**
> **Please make sure to use one of the following:**
> * IP Address - `192.168.1.1`
> * CIDR - `192.168.1.0/24`
> * Range - `192.168.1.1-192.168.1.100`

#### IP Limiter
The IP Limiter has been completely rewritten. The available configurations are:
```json
"ipLimiter.enable": "True",
"ipLimiter.maxConnectionsPerIP": 10,
"ipLimiter.clearConnectionAttemptsDuration": "00:00:00:10",
"ipLimiter.clearThrottledDuration": "00:00:02:00",
```

The IP Limiter is set up to prevent spamming connections from the same IP. Every time an IP connects, it is added to a connection list. After 10 attempts, the IP is added to the throttle list. To keep the system fast, the connection list is entirely wiped every 10 seconds, and the throttle list is entirely wiped every 2 minutes.
2024-01-20 14:25:12 -08:00

414 lines
12 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using Server.Accounting;
using Server.Engines.Help;
using Server.Logging;
using Server.Network;
using Server.Regions;
namespace Server.Misc;
public static class AccountHandler
{
private static readonly ILogger logger = LogFactory.GetLogger(typeof(AccountHandler));
private static int MaxAccountsPerIP;
private static bool AutoAccountCreation;
private static bool RestrictDeletion = !TestCenter.Enabled;
private static TimeSpan DeleteDelay = TimeSpan.FromDays(7.0);
private static bool PasswordCommandEnabled;
private static Dictionary<IPAddress, int> m_IPTable;
private static char[] m_ForbiddenChars = { '<', '>', ':', '"', '/', '\\', '|', '?', '*' };
public static AccessLevel LockdownLevel { get; set; }
public static Dictionary<IPAddress, int> IPTable
{
get
{
if (m_IPTable == null)
{
m_IPTable = new Dictionary<IPAddress, int>();
foreach (Account a in Accounts.GetAccounts())
{
if (a.LoginIPs.Length > 0)
{
var ip = a.LoginIPs[0];
m_IPTable[ip] = (m_IPTable.TryGetValue(ip, out var value) ? value : 0) + 1;
}
}
}
return m_IPTable;
}
}
public static void Configure()
{
MaxAccountsPerIP = ServerConfiguration.GetOrUpdateSetting("accountHandler.maxAccountsPerIP", 1);
AutoAccountCreation = ServerConfiguration.GetOrUpdateSetting("accountHandler.enableAutoAccountCreation", true);
PasswordCommandEnabled = ServerConfiguration.GetOrUpdateSetting(
"accountHandler.enablePlayerPasswordCommand",
false
);
}
public static void Initialize()
{
EventSink.DeleteRequest += EventSink_DeleteRequest;
EventSink.AccountLogin += EventSink_AccountLogin;
EventSink.GameLogin += EventSink_GameLogin;
if (PasswordCommandEnabled)
{
CommandSystem.Register("Password", AccessLevel.Player, Password_OnCommand);
}
}
[Usage("Password <newPassword> <repeatPassword>")]
[Description(
"Changes the password of the commanding players account. Requires the same C-class IP address as the account's creator."
)]
public static void Password_OnCommand(CommandEventArgs e)
{
var from = e.Mobile;
if (from.Account is not Account acct)
{
return;
}
var accessList = acct.LoginIPs;
if (accessList.Length == 0)
{
return;
}
var ns = from.NetState;
if (ns == null)
{
return;
}
if (e.Length == 0)
{
from.SendMessage("You must specify the new password.");
return;
}
if (e.Length == 1)
{
from.SendMessage("To prevent potential typing mistakes, you must type the password twice. Use the format:");
from.SendMessage("Password \"(newPassword)\" \"(repeated)\"");
return;
}
var pass = e.GetString(0);
var pass2 = e.GetString(1);
if (pass != pass2)
{
from.SendMessage("The passwords do not match.");
return;
}
var isSafe = true;
for (var i = 0; isSafe && i < pass.Length; ++i)
{
isSafe = pass[i] >= 0x20 && pass[i] < 0x7F;
}
if (!isSafe)
{
from.SendMessage("That is not a valid password.");
return;
}
try
{
var ipAddress = ns.Address;
if (accessList[0].MatchClassC(ipAddress))
{
acct.SetPassword(pass);
from.SendMessage("The password to your account has changed.");
}
else
{
var entry = PageQueue.GetEntry(from);
if (entry != null)
{
if (entry.Message.StartsWithOrdinal("[Automated: Change Password]"))
{
from.SendMessage("You already have a password change request in the help system queue.");
}
else
{
from.SendMessage("Your IP address does not match that which created this account.");
}
}
else if (PageQueue.CheckAllowedToPage(from))
{
from.SendMessage(
"Your IP address does not match that which created this account. A page has been entered into the help system on your behalf."
);
/* The next available Counselor/Game Master will respond as soon as possible.
* Please check your Journal for messages every few minutes.
*/
from.SendLocalizedMessage(501234, "", 0x35);
PageQueue.Enqueue(
new PageEntry(
from,
$"[Automated: Change Password]<br>Desired password: {pass}<br>Current IP address: {ipAddress}<br>Account IP address: {accessList[0]}",
PageType.Account
)
);
}
}
}
catch
{
// ignored
}
}
private static void EventSink_DeleteRequest(NetState state, int index)
{
if (state.Account is not Account acct)
{
state.Disconnect("Attempted to delete a character but the account could not be found.");
return;
}
DeleteResultType res;
if (index < 0 || index >= acct.Length)
{
res = DeleteResultType.BadRequest;
}
else
{
var m = acct[index];
if (m == null)
{
res = DeleteResultType.CharNotExist;
}
else if (m.NetState != null)
{
res = DeleteResultType.CharBeingPlayed;
}
else if (acct.AccessLevel == AccessLevel.Player && RestrictDeletion && Core.Now < m.Created + DeleteDelay)
{
res = DeleteResultType.CharTooYoung;
}
// Don't need to check current location, if netstate is null, they're logged out
else if (
m.AccessLevel == AccessLevel.Player &&
Region.Find(m.LogoutLocation, m.LogoutMap).IsPartOf<JailRegion>()
)
{
res = DeleteResultType.BadRequest;
}
else
{
state.LogInfo($"Deleting character {index} ({m.Serial})");
acct.Comments.Add(new AccountComment("System", $"Character #{index + 1} {m} deleted by {state}"));
m.Delete();
EventSink.InvokePlayerDeleted(m);
state.SendCharacterListUpdate(acct);
return;
}
}
state.SendCharacterDeleteResult(res);
state.SendCharacterListUpdate(acct);
}
public static bool CanCreate(IPAddress ip) =>
!IPTable.TryGetValue(ip, out var result) || result < MaxAccountsPerIP;
private static bool IsForbiddenChar(char c)
{
for (var i = 0; i < m_ForbiddenChars.Length; ++i)
{
if (c == m_ForbiddenChars[i])
{
return true;
}
}
return false;
}
private static Account CreateAccount(NetState state, string un, string pw)
{
if (un.Length == 0 || pw.Length == 0)
{
return null;
}
var isSafe = !(un.StartsWithOrdinal(" ") ||
un.EndsWithOrdinal(" ") ||
un.EndsWithOrdinal("."));
for (var i = 0; isSafe && i < un.Length; ++i)
{
isSafe = un[i] >= 0x20 && un[i] < 0x7F && !IsForbiddenChar(un[i]);
}
for (var i = 0; isSafe && i < pw.Length; ++i)
{
isSafe = pw[i] >= 0x20 && pw[i] < 0x7F;
}
if (!isSafe)
{
return null;
}
if (!CanCreate(state.Address))
{
logger.Information(
$"Login: {{NetState}} Account '{{Username}}' not created, ip already has {{AccountCount}} account{(MaxAccountsPerIP == 1 ? "" : "s")}.",
state,
un,
MaxAccountsPerIP
);
return null;
}
logger.Information("Login: {NetState}: Creating new account '{Username}'", state, un);
var a = new Account(un, pw);
return a;
}
public static void EventSink_AccountLogin(AccountLoginEventArgs e)
{
var un = e.Username;
var pw = e.Password;
e.Accepted = false;
if (Accounts.GetAccount(un) is not Account acct)
{
// To prevent someone from making an account of just '' or a bunch of meaningless spaces
if (AutoAccountCreation && un.Trim().Length > 0)
{
e.State.Account = acct = CreateAccount(e.State, un, pw);
e.Accepted = acct?.CheckAccess(e.State) ?? false;
if (!e.Accepted)
{
e.RejectReason = ALRReason.BadComm;
}
}
else
{
logger.Information("Login: {NetState} Invalid username '{Username}'", e.State, un);
e.RejectReason = ALRReason.Invalid;
}
}
else if (!acct.HasAccess(e.State))
{
logger.Information("Login: {NetState} Access denied for '{Username}'", e.State, un);
e.RejectReason = LockdownLevel > AccessLevel.Player ? ALRReason.BadComm : ALRReason.BadPass;
}
else if (!acct.CheckPassword(pw))
{
logger.Information("Login: {NetState} Invalid password for '{Username}'", e.State, un);
e.RejectReason = ALRReason.BadPass;
}
else if (acct.Banned)
{
logger.Information("Login: {NetState} Banned account '{Username}'", e.State, un);
e.RejectReason = ALRReason.Blocked;
}
else
{
logger.Information("Login: {NetState} Valid credentials for '{Username}'", e.State, un);
e.State.Account = acct;
e.Accepted = true;
acct.LogAccess(e.State);
}
if (!e.Accepted)
{
AccountAttackLimiter.RegisterInvalidAccess(e.State);
}
}
public static void EventSink_GameLogin(GameLoginEventArgs e)
{
var un = e.Username;
var pw = e.Password;
if (Accounts.GetAccount(un) is not Account acct)
{
e.Accepted = false;
}
else if (!acct.HasAccess(e.State))
{
logger.Information("Login: {NetState} Access denied for '{Username}'", e.State, un);
e.Accepted = false;
}
else if (!acct.CheckPassword(pw))
{
logger.Information("Login: {NetState} Invalid password for '{Username}'", e.State, un);
e.Accepted = false;
}
else if (acct.Banned)
{
logger.Information("Login: {NetState} Banned account '{Username}'", e.State, un);
e.Accepted = false;
}
else
{
acct.LogAccess(e.State);
logger.Information("Login: {NetState} Account '{Username}' at character list", e.State, un);
e.State.Account = acct;
e.Accepted = true;
e.CityInfo = CharacterCreation.GetStartingCities(acct.Young);
}
if (!e.Accepted)
{
AccountAttackLimiter.RegisterInvalidAccess(e.State);
}
}
public static bool CheckAccount(Mobile mobCheck, Mobile accCheck)
{
if (accCheck?.Account is Account a)
{
for (var i = 0; i < a.Length; ++i)
{
if (a[i] == mobCheck)
{
return true;
}
}
}
return false;
}
}