From 6bdeafcf8c78e145595f52e885356be1210abe91 Mon Sep 17 00:00:00 2001
From: Mark McDowall <mark@mcdowall.ca>
Date: Sun, 4 Dec 2022 22:08:56 -0800
Subject: [PATCH] Fixed: Improve Bind Address validation and help text

Closes #622
---
 frontend/src/Settings/General/HostSettings.js |  2 +-
 .../IsValidIPAddressFixture.cs                | 25 +++++++++++++++++++
 .../Extensions/StringExtensions.cs            | 22 ++++++++++++++++
 src/NzbDrone.Core/Validation/IpValidation.cs  | 22 +++-------------
 .../Config/HostConfigController.cs            |  4 +--
 5 files changed, 53 insertions(+), 22 deletions(-)
 create mode 100644 src/NzbDrone.Common.Test/ExtensionTests/StringExtensionTests/IsValidIPAddressFixture.cs

diff --git a/frontend/src/Settings/General/HostSettings.js b/frontend/src/Settings/General/HostSettings.js
index e22f18698..bcde83670 100644
--- a/frontend/src/Settings/General/HostSettings.js
+++ b/frontend/src/Settings/General/HostSettings.js
@@ -39,7 +39,7 @@ function HostSettings(props) {
         <FormInputGroup
           type={inputTypes.TEXT}
           name="bindAddress"
-          helpText="Valid IPv4 address or '*' for all interfaces"
+          helpText="Valid IP address, localhost or '*' for all interfaces"
           helpTextWarning="Requires restart to take effect"
           onChange={onInputChange}
           {...bindAddress}
diff --git a/src/NzbDrone.Common.Test/ExtensionTests/StringExtensionTests/IsValidIPAddressFixture.cs b/src/NzbDrone.Common.Test/ExtensionTests/StringExtensionTests/IsValidIPAddressFixture.cs
new file mode 100644
index 000000000..0e2ac3d63
--- /dev/null
+++ b/src/NzbDrone.Common.Test/ExtensionTests/StringExtensionTests/IsValidIPAddressFixture.cs
@@ -0,0 +1,25 @@
+using System.Globalization;
+using FluentAssertions;
+using NUnit.Framework;
+using NzbDrone.Common.Extensions;
+
+namespace NzbDrone.Common.Test.ExtensionTests.StringExtensionTests
+{
+    [TestFixture]
+    public class IsValidIPAddressFixture
+    {
+        [TestCase("192.168.0.1")]
+        [TestCase("::1")]
+        [TestCase("2001:db8:4006:812::200e")]
+        public void should_validate_ip_address(string input)
+        {
+            input.IsValidIpAddress().Should().BeTrue();
+        }
+
+        [TestCase("sonarr.tv")]
+        public void should_not_parse_non_ip_address(string input)
+        {
+            input.IsValidIpAddress().Should().BeFalse();
+        }
+    }
+}
diff --git a/src/NzbDrone.Common/Extensions/StringExtensions.cs b/src/NzbDrone.Common/Extensions/StringExtensions.cs
index 55085136e..258025213 100644
--- a/src/NzbDrone.Common/Extensions/StringExtensions.cs
+++ b/src/NzbDrone.Common/Extensions/StringExtensions.cs
@@ -2,6 +2,8 @@ using System;
 using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
+using System.Net;
+using System.Net.Sockets;
 using System.Text;
 using System.Text.RegularExpressions;
 
@@ -215,5 +217,25 @@ namespace NzbDrone.Common.Extensions
                 .Replace("'", "%27")
                 .Replace("%7E", "~");
         }
+
+        public static bool IsValidIpAddress(this string value)
+        {
+            if (!IPAddress.TryParse(value, out var parsedAddress))
+            {
+                return false;
+            }
+
+            if (parsedAddress.Equals(IPAddress.Parse("255.255.255.255")))
+            {
+                return false;
+            }
+
+            if (parsedAddress.IsIPv6Multicast)
+            {
+                return false;
+            }
+
+            return parsedAddress.AddressFamily == AddressFamily.InterNetwork || parsedAddress.AddressFamily == AddressFamily.InterNetworkV6;
+        }
     }
 }
diff --git a/src/NzbDrone.Core/Validation/IpValidation.cs b/src/NzbDrone.Core/Validation/IpValidation.cs
index 7037ae1ea..eb5863caa 100644
--- a/src/NzbDrone.Core/Validation/IpValidation.cs
+++ b/src/NzbDrone.Core/Validation/IpValidation.cs
@@ -1,30 +1,14 @@
-using System.Net;
-using System.Net.Sockets;
 using FluentValidation;
 using FluentValidation.Validators;
+using NzbDrone.Common.Extensions;
 
 namespace NzbDrone.Core.Validation
 {
     public static class IpValidation
     {
-        public static IRuleBuilderOptions<T, string> ValidIp4Address<T>(this IRuleBuilder<T, string> ruleBuilder)
+        public static IRuleBuilderOptions<T, string> ValidIpAddress<T>(this IRuleBuilder<T, string> ruleBuilder)
         {
-            return ruleBuilder.Must(x =>
-            {
-                IPAddress parsedAddress;
-
-                if (!IPAddress.TryParse(x, out parsedAddress))
-                {
-                    return false;
-                }
-
-                if (parsedAddress.Equals(IPAddress.Parse("255.255.255.255")))
-                {
-                    return false;
-                }
-
-                return parsedAddress.AddressFamily == AddressFamily.InterNetwork;
-            }).WithMessage("Must contain wildcard (*) or a valid IPv4 Address");
+            return ruleBuilder.Must(x => x.IsValidIpAddress()).WithMessage("Must contain wildcard (*) or a valid IP Address");
         }
 
         public static IRuleBuilderOptions<T, string> NotListenAllIp4Address<T>(this IRuleBuilder<T, string> ruleBuilder)
diff --git a/src/Sonarr.Api.V3/Config/HostConfigController.cs b/src/Sonarr.Api.V3/Config/HostConfigController.cs
index 121b76bde..883e3b296 100644
--- a/src/Sonarr.Api.V3/Config/HostConfigController.cs
+++ b/src/Sonarr.Api.V3/Config/HostConfigController.cs
@@ -33,9 +33,9 @@ namespace Sonarr.Api.V3.Config
             _userService = userService;
 
             SharedValidator.RuleFor(c => c.BindAddress)
-                           .ValidIp4Address()
+                           .ValidIpAddress()
                            .NotListenAllIp4Address()
-                           .When(c => c.BindAddress != "*");
+                           .When(c => c.BindAddress != "*" && c.BindAddress != "localhost");
 
             SharedValidator.RuleFor(c => c.Port).ValidPort();