backend: require confirmation for signed channel updates [CI]

backend/shared/MoShiro.Measurement/Platform/Ipv6Diagnostics.cs

@@ -0,0 +1,154 @@
+using System.Globalization;
+using System.Net;
+using System.Net.NetworkInformation;
+using System.Net.Sockets;
+using MoShiro.Protocol;
+
+namespace MoShiro.Measurement;
+
+/// <summary>诊断采集进程所在的网络环境。宿主网络容器看到的是主机；桥接容器看到自己的网络环境。</summary>
+public static class Ipv6Diagnostics
+{
+    public static Ipv6Diagnostic Sample(bool? listening = null, string? networkScope = null, string? hostProcRoot = null)
+    {
+        bool supported = Socket.OSSupportsIPv6;
+        bool? address = null;
+        bool? route = null;
+        if (supported)
+        {
+            if (OperatingSystem.IsLinux())
+            {
+                address = ParseAddresses(Read("/proc/net/if_inet6"));
+                route = ParseRoutes(Read("/proc/net/ipv6_route"));
+            }
+            else if (OperatingSystem.IsWindows() || OperatingSystem.IsMacOS())
+            {
+                try
+                {
+                    address = false;
+                    route = false;
+                    foreach (NetworkInterface adapter in NetworkInterface.GetAllNetworkInterfaces())
+                    {
+                        if (adapter.OperationalStatus != OperationalStatus.Up || adapter.NetworkInterfaceType == NetworkInterfaceType.Loopback)
+                        {
+                            continue;
+                        }
+
+                        IPInterfaceProperties properties = adapter.GetIPProperties();
+                        foreach (UnicastIPAddressInformation unicast in properties.UnicastAddresses)
+                        {
+                            if (IsGlobal(unicast.Address))
+                            {
+                                address = true;
+                            }
+                        }
+
+                        foreach (GatewayIPAddressInformation gateway in properties.GatewayAddresses)
+                        {
+                            if (gateway.Address.AddressFamily == AddressFamily.InterNetworkV6 && !gateway.Address.Equals(IPAddress.IPv6Any))
+                            {
+                                route = true;
+                            }
+                        }
+                    }
+                }
+                catch (Exception ex) when (ex is NetworkInformationException or PlatformNotSupportedException)
+                {
+                    address = null;
+                    route = null;
+                }
+            }
+        }
+
+        string scope = networkScope is "host" or "container" ? networkScope
+            : File.Exists("/run/.containerenv") || File.Exists("/.dockerenv") ? "container" : "host";
+        bool? hostAddress = scope == "host" ? address : null;
+        bool? hostRoute = scope == "host" ? route : null;
+        if (scope == "container" && OperatingSystem.IsLinux() && hostProcRoot is not null)
+        {
+            // /host/proc/net 通常指向当前进程的网络空间；宿主 PID 1 才是宿主网络。
+            hostAddress = ParseAddresses(Read(Path.Combine(hostProcRoot, "1/net/if_inet6")));
+            hostRoute = ParseRoutes(Read(Path.Combine(hostProcRoot, "1/net/ipv6_route")));
+        }
+
+        Ipv6Diagnostic result = Evaluate(supported, listening, address, route);
+        result.NetworkScope = scope;
+        result.HostHasGlobalAddress = hostAddress;
+        result.HostHasDefaultRoute = hostRoute;
+        if (scope == "container" && address == false && hostAddress == true)
+        {
+            result.State = "container_network_not_ready";
+        }
+
+        return result;
+    }
+
+    public static Ipv6Diagnostic Evaluate(bool supported, bool? listening, bool? address, bool? route) => new()
+    {
+        SocketSupported = supported,
+        Listening = listening,
+        HasGlobalAddress = address,
+        HasDefaultRoute = route,
+        State = !supported ? "unsupported" : address == false ? "no_global_address" : listening == false ? "not_listening"
+            : route == false ? "no_default_route" : address is null || route is null ? "unknown" : "ready",
+    };
+
+    public static bool? ParseAddresses(string? text)
+    {
+        if (text is null)
+        {
+            return null;
+        }
+
+        foreach (string line in text.Split('\n'))
+        {
+            string[] fields = line.Split((char[]?)null, StringSplitOptions.RemoveEmptyEntries);
+            if (fields.Length != 6 || fields[0].Length != 32 || fields[0][0] is not ('2' or '3') || fields[3] != "00")
+            {
+                continue;
+            }
+
+            // tentative、DAD failed 和 deprecated 地址不能作为就绪的公网地址。
+            if (uint.TryParse(fields[4], NumberStyles.HexNumber, CultureInfo.InvariantCulture, out uint flags) && (flags & 0x68) == 0)
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    public static bool? ParseRoutes(string? text)
+    {
+        if (text is null)
+        {
+            return null;
+        }
+
+        foreach (string line in text.Split('\n'))
+        {
+            string[] fields = line.Split((char[]?)null, StringSplitOptions.RemoveEmptyEntries);
+            if (fields.Length == 10 && fields[0] == "00000000000000000000000000000000" && fields[1] == "00" && fields[9] != "lo"
+                && uint.TryParse(fields[8], NumberStyles.HexNumber, CultureInfo.InvariantCulture, out uint flags) && (flags & 1) != 0 && (flags & 0x200) == 0)
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    private static bool IsGlobal(IPAddress address) => address.AddressFamily == AddressFamily.InterNetworkV6 && (address.GetAddressBytes()[0] & 0xE0) == 0x20;
+
+    private static string? Read(string path)
+    {
+        try
+        {
+            return File.Exists(path) ? File.ReadAllText(path) : null;
+        }
+        catch (Exception ex) when (ex is IOException or UnauthorizedAccessException)
+        {
+            return null;
+        }
+    }
+}