IPBanningModule (#420)

* IPBanningModule

* Adding AccessAttempts

* Extensions and constructors
Basic test

* IP Parsing

* Min fix IP Parser

* Performance improvements

* FailRegex as static ConcurrentDictionary

* Extension methods for init.
Xmldoc.

* Unit Tests

* More unit test

* Code Style

* Fix extension methods

* IPParserTest

* Code Style

EmbedIO.sln

@@ -1,13 +1,12 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio 15
-VisualStudioVersion = 15.0.26730.16
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.29609.76
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{97BC259A-4E78-4BA8-8F4D-2656BC78BB34}"
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{73F25F81-0412-412E-89C9-BAD33E9BCCDE}"
 	ProjectSection(SolutionItems) = preProject
-		.travis.yml = .travis.yml
 		appveyor.yml = appveyor.yml
 		LICENSE = LICENSE
 		README.md = README.md

src/EmbedIO.Samples/Program.cs

@@ -1,10 +1,12 @@
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
 using EmbedIO.Actions;
 using EmbedIO.Files;
+using EmbedIO.Security;
 using EmbedIO.WebApi;
 using Swan;
 using Swan.Logging;
@@ -60,6 +62,13 @@ private static WebServer CreateWebServer(string url)
             var server = new WebServer(o => o
                     .WithUrlPrefix(url)
                     .WithMode(HttpListenerMode.EmbedIO))
+                .WithIPBanning(o => o
+                    .WithWhitelist(
+                        "",
+                        "172.16.16.124",
+                        "172.16.17.1/24",
+                        "192.168.1-2.2-5")
+                    .WithRules("(404 Not Found)+"), 5,5)
                 .WithLocalSessionManager()
                 .WithCors(
                     // Origins, separated by comma without last slash

src/EmbedIO/Security/BannedInfo.cs

@@ -0,0 +1,25 @@
+using System.Net;
+
+namespace EmbedIO.Security
+{
+    /// <summary>
+    /// Represents the info af a banned IP address.
+    /// </summary>
+    public class BannedInfo
+    {
+        /// <summary>
+        /// Gets or sets the banned IP address.
+        /// </summary>
+        public IPAddress IPAddress { get; set; }
+
+        /// <summary>
+        /// Gets or sets until when the IP will remain ban.
+        /// </summary>
+        public long BanUntil { get; set; }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether this instance was explicitly banned by user.
+        /// </summary>
+        public bool IsExplicit { get; set; }
+    }
+}

src/EmbedIO/Security/IPBanningModule.cs

@@ -0,0 +1,301 @@
+using EmbedIO.Utilities;
+using Swan;
+using Swan.Logging;
+using Swan.Threading;
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Text.RegularExpressions;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace EmbedIO.Security
+{
+    /// <summary>
+    /// A module for ban IPs that show the malicious signs, based on scanning log messages.
+    /// </summary>
+    /// <seealso cref="WebModuleBase" />
+    public class IPBanningModule : WebModuleBase, ILogger
+    {
+        /// <summary>
+        /// The default ban time, in minutes.
+        /// </summary>
+        public const int DefaultBanTime = 30;
+
+        /// <summary>
+        /// The default maximum retries per minute.
+        /// </summary>
+        public const int DefaultMaxRetry = 10;
+
+        private static readonly ConcurrentDictionary<IPAddress, ConcurrentBag<long>> AccessAttempts = new ConcurrentDictionary<IPAddress, ConcurrentBag<long>>();
+        private static readonly ConcurrentDictionary<IPAddress, BannedInfo> Blacklist = new ConcurrentDictionary<IPAddress, BannedInfo>();
+        private static readonly ConcurrentDictionary<string, Regex> FailRegex = new ConcurrentDictionary<string, Regex>();
+        private static readonly PeriodicTask? Purger;
+
+        private readonly List<IPAddress> _whitelist = new List<IPAddress>();
+        private readonly int _banTime;
+        private readonly int _maxRetry;
+        private bool _disposedValue;
+
+        static IPBanningModule()
+        {
+            Purger = new PeriodicTask(TimeSpan.FromMinutes(1), ct =>
+                {
+                    PurgeBlackList();
+                    PurgeAccessAttempts();
+
+                    return Task.CompletedTask;
+                });
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="IPBanningModule"/> class.
+        /// </summary>
+        /// <param name="baseRoute">The base route.</param>
+        /// <param name="failRegex">A collection of regex to match the log messages against.</param>
+        /// <param name="banTime">The time that an IP will remain ban, in minutes.</param>
+        /// <param name="maxRetry">The maximum number of failed attempts before banning an IP.</param>
+        public IPBanningModule(string baseRoute,
+            IEnumerable<string> failRegex,
+            int banTime = DefaultBanTime,
+            int maxRetry = DefaultMaxRetry)
+            : this(baseRoute, failRegex, null, banTime, maxRetry)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="IPBanningModule"/> class.
+        /// </summary>
+        /// <param name="baseRoute">The base route.</param>
+        /// <param name="failRegex">A collection of regex to match the log messages against.</param>
+        /// <param name="whitelist">A collection of valid IPs that never will be banned.</param>
+        /// <param name="banTime">The time that an IP will remain ban, in minutes.</param>
+        /// <param name="maxRetry">The maximum number of failed attempts before banning an IP.</param>
+        public IPBanningModule(string baseRoute,
+            IEnumerable<string>? failRegex = null,
+            IEnumerable<string>? whitelist = null,
+            int banTime = DefaultBanTime,
+            int maxRetry = DefaultMaxRetry)
+            : base(baseRoute)
+        {
+            if (failRegex != null)
+                AddRules(failRegex);
+
+            _banTime = banTime;
+            _maxRetry = maxRetry;
+            AddToWhitelist(whitelist);
+            Logger.RegisterLogger(this);
+        }
+
+        /// <inheritdoc />
+        public override bool IsFinalHandler => false;
+
+        /// <inheritdoc />
+        public LogLevel LogLevel => LogLevel.Trace;
+
+        private IPAddress? ClientAddress { get; set; }
+
+        /// <summary>
+        /// Gets the list of current banned IPs.
+        /// </summary>
+        /// <returns>A collection of <see cref="BannedInfo"/> in the blacklist.</returns>
+        public static IEnumerable<BannedInfo> GetBannedIPs() =>
+            Blacklist.Values.ToList();
+
+        /// <summary>
+        /// Tries to ban an IP explicitly.
+        /// </summary>
+        /// <param name="address">The IP address to ban.</param>
+        /// <param name="minutes">The time in minutes that the IP will remain ban.</param>
+        /// <param name="isExplicit">if set to <c>true</c> [is explicit].</param>
+        /// <returns>
+        ///     <c>true</c> if the IP was added to the blacklist; otherwise, <c>false</c>.
+        /// </returns>
+        public static bool TryBanIP(IPAddress address, int minutes, bool isExplicit = true) =>
+            TryBanIP(address, DateTime.Now.AddMinutes(minutes), isExplicit);
+
+        /// <summary>
+        /// Tries to ban an IP explicitly.
+        /// </summary>
+        /// <param name="address">The IP address to ban.</param>
+        /// <param name="banTime">An <see cref="TimeSpan"/> that sets the time the IP will remain ban.</param>
+        /// <param name="isExplicit">if set to <c>true</c> [is explicit].</param>
+        /// <returns>
+        ///     <c>true</c> if the IP was added to the blacklist; otherwise, <c>false</c>.
+        /// </returns>
+        public static bool TryBanIP(IPAddress address, TimeSpan banTime, bool isExplicit = true) =>
+            TryBanIP(address, DateTime.Now.Add(banTime), isExplicit);
+
+        /// <summary>
+        /// Tries to ban an IP explicitly.
+        /// </summary>
+        /// <param name="address">The IP address to ban.</param>
+        /// <param name="banUntil">A <see cref="DateTime"/> that sets until when the IP will remain ban.</param>
+        /// <param name="isExplicit">if set to <c>true</c> [is explicit].</param>
+        /// <returns>
+        ///     <c>true</c> if the IP was added to the blacklist; otherwise, <c>false</c>.
+        /// </returns>
+        public static bool TryBanIP(IPAddress address, DateTime banUntil, bool isExplicit = true)
+        {
+            if (Blacklist.ContainsKey(address))
+            {
+                var bannedInfo = Blacklist[address];
+                bannedInfo.BanUntil = banUntil.Ticks;
+                bannedInfo.IsExplicit = isExplicit;
+
+                return true;
+            }
+
+            return Blacklist.TryAdd(address, new BannedInfo()
+            {
+                IPAddress = address,
+                BanUntil = banUntil.Ticks,
+                IsExplicit = isExplicit,
+            });
+        }
+
+        /// <summary>
+        /// Tries to unban an IP explicitly.
+        /// </summary>
+        /// <param name="address">The IP address.</param>
+        /// <returns>
+        ///     <c>true</c> if the IP was removed from the blacklist; otherwise, <c>false</c>.
+        /// </returns>
+        public static bool TryUnbanIP(IPAddress address) =>
+            Blacklist.TryRemove(address, out _);
+
+        /// <inheritdoc />
+        public void Log(LogMessageReceivedEventArgs logEvent)
+        {
+            // Process Log
+            if (string.IsNullOrWhiteSpace(logEvent.Message) ||
+                ClientAddress == null ||
+                !FailRegex.Any() ||
+                _whitelist.Contains(ClientAddress) ||
+                Blacklist.ContainsKey(ClientAddress))
+                return;
+
+            foreach (var regex in FailRegex.Values)
+            {
+                try
+                {
+                    if (!regex.IsMatch(logEvent.Message)) continue;
+
+                    // Add to list
+                    AddAccessAttempt(ClientAddress);
+                    UpdateBlackList();
+                    break;
+                }
+                catch (RegexMatchTimeoutException ex)
+                {
+                    $"Timeout trying to match '{ex.Input}' with pattern '{ex.Pattern}'.".Error(nameof(IPBanningModule));
+                }
+            }
+        }
+
+        /// <inheritdoc />
+        public void Dispose() =>
+            Dispose(true);
+
+        internal void AddRules(IEnumerable<string> patterns)
+        {
+            foreach (var pattern in patterns)
+                AddRule(pattern);
+        }
+
+        internal void AddRule(string pattern)
+        {
+            try
+            {
+                FailRegex.TryAdd(pattern, new Regex(pattern, RegexOptions.Compiled | RegexOptions.CultureInvariant, TimeSpan.FromMilliseconds(500)));
+            }
+            catch (Exception ex)
+            {
+                ex.Log(nameof(IPBanningModule), $"Invalid regex - '{pattern}'.");
+            }
+        }
+
+        internal void AddToWhitelist(IEnumerable<string> whitelist) =>
+            AddToWhitelistAsync(whitelist).GetAwaiter().GetResult();
+
+        internal async Task AddToWhitelistAsync(IEnumerable<string> whitelist)
+        {
+            if (whitelist?.Any() != true)
+                return;
+
+            foreach (var address in whitelist)
+            {
+                var addressees = await IPParser.Parse(address).ConfigureAwait(false);
+                _whitelist.AddRange(addressees.Where(x => !_whitelist.Contains(x)));
+            }
+        }
+
+        /// <inheritdoc />
+        protected override Task OnRequestAsync(IHttpContext context)
+        {
+            ClientAddress = context.Request.RemoteEndPoint.Address;
+            if (!Blacklist.ContainsKey(ClientAddress)) 
+                return Task.CompletedTask;
+
+            context.SetHandled();
+            throw HttpException.Forbidden();
+        }
+
+        /// <summary>
+        /// Releases unmanaged and - optionally - managed resources.
+        /// </summary>
+        /// <param name="disposing"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
+        protected virtual void Dispose(bool disposing)
+        {
+            if (_disposedValue) return;
+            if (disposing)
+            {
+                _whitelist.Clear();
+            }
+
+            _disposedValue = true;
+        }
+
+        private static void AddAccessAttempt(IPAddress address)
+        {
+            if (AccessAttempts.ContainsKey(address))
+                AccessAttempts[address].Add(DateTime.Now.Ticks);
+            else
+                AccessAttempts.TryAdd(address, new ConcurrentBag<long>() { DateTime.Now.Ticks });
+        }
+
+        private static void PurgeBlackList()
+        {
+            foreach (var k in Blacklist.Keys)
+            {
+                if (DateTime.Now.Ticks > Blacklist[k].BanUntil)
+                    Blacklist.TryRemove(k, out _);
+            }
+        }
+
+        private static void PurgeAccessAttempts()
+        {
+            var banDate = DateTime.Now.AddMinutes(-1).Ticks;
+
+            foreach (var k in AccessAttempts.Keys)
+            {
+                var recentAttempts = new ConcurrentBag<long>(AccessAttempts[k].Where(x => x >= banDate));
+                if (!recentAttempts.Any())
+                    AccessAttempts.TryRemove(k, out _);
+                else
+                    Interlocked.Exchange(ref recentAttempts, AccessAttempts[k]);
+            }
+        }
+
+        private void UpdateBlackList()
+        {
+            var time = DateTime.Now.AddMinutes(-1).Ticks;
+            if ((AccessAttempts[ClientAddress]?.Where(x => x >= time).Count() >= _maxRetry))
+            {
+                TryBanIP(ClientAddress, _banTime, false);
+            }
+        }
+    }
+}