From 50bb54ff60dc67dee54a1b772eeae1ce454066b4 Mon Sep 17 00:00:00 2001 From: Louis R Date: Sun, 3 Mar 2024 06:20:36 +0100 Subject: [PATCH] Fixed: Don't disable IPv6 in IPv6-only Environment (cherry picked from commit 13af6f57796e54c3949cf340e03f020e6f8575c4) --- .../Http/Dispatchers/ManagedHttpDispatcher.cs | 20 +++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/src/NzbDrone.Common/Http/Dispatchers/ManagedHttpDispatcher.cs b/src/NzbDrone.Common/Http/Dispatchers/ManagedHttpDispatcher.cs index e3459f985..756e3f08e 100644 --- a/src/NzbDrone.Common/Http/Dispatchers/ManagedHttpDispatcher.cs +++ b/src/NzbDrone.Common/Http/Dispatchers/ManagedHttpDispatcher.cs @@ -1,7 +1,9 @@ using System; using System.IO; +using System.Linq; using System.Net; using System.Net.Http; +using System.Net.NetworkInformation; using System.Net.Security; using System.Net.Sockets; using System.Text; @@ -249,6 +251,18 @@ namespace NzbDrone.Common.Http.Dispatchers return _credentialCache.Get("credentialCache", () => new CredentialCache()); } + private static bool HasRoutableIPv4Address() + { + // Get all IPv4 addresses from all interfaces and return true if there are any with non-loopback addresses + var networkInterfaces = NetworkInterface.GetAllNetworkInterfaces(); + + return networkInterfaces.Any(ni => + ni.OperationalStatus == OperationalStatus.Up && + ni.GetIPProperties().UnicastAddresses.Any(ip => + ip.Address.AddressFamily == AddressFamily.InterNetwork && + !IPAddress.IsLoopback(ip.Address))); + } + private static async ValueTask onConnect(SocketsHttpConnectionContext context, CancellationToken cancellationToken) { // Until .NET supports an implementation of Happy Eyeballs (https://tools.ietf.org/html/rfc8305#section-2), let's make IPv4 fallback work in a simple way. @@ -272,10 +286,8 @@ namespace NzbDrone.Common.Http.Dispatchers } catch { - // very naively fallback to ipv4 permanently for this execution based on the response of the first connection attempt. - // note that this may cause users to eventually get switched to ipv4 (on a random failure when they are switching networks, for instance) - // but in the interest of keeping this implementation simple, this is acceptable. - useIPv6 = false; + // Do not retry IPv6 if a routable IPv4 address is available, otherwise continue to attempt IPv6 connections. + useIPv6 = !HasRoutableIPv4Address(); } finally {