Implement IResolver (#442)

* Implement IResolver

- GetAddrInfo & GetNameInfo still need to be implemented.

* Address comments

* Use MakeError

3 files changed, 414 insertions, 1 deletions

diff --git a/Ryujinx.HLE/HOS/Services/Sfdnsres/GaiError.cs b/Ryujinx.HLE/HOS/Services/Sfdnsres/GaiError.cs
new file mode 100644
index 00000000..65d54577
--- /dev/null
+++ b/Ryujinx.HLE/HOS/Services/Sfdnsres/GaiError.cs
@@ -0,0 +1,22 @@
+namespace Ryujinx.HLE.HOS.Services.Sfdnsres
+{
+    enum GaiError
+    {
+        Success,
+        AddressFamily,
+        Again,
+        BadFlags,
+        Fail,
+        Family,
+        Memory,
+        NoData,
+        NoName,
+        Service,
+        SocketType,
+        System,
+        BadHints,
+        Protocol,
+        Overflow,
+        Max,
+    }
+}
diff --git a/Ryujinx.HLE/HOS/Services/Sfdnsres/IResolver.cs b/Ryujinx.HLE/HOS/Services/Sfdnsres/IResolver.cs
index 26dbedf4..0ca43eda 100644
--- a/Ryujinx.HLE/HOS/Services/Sfdnsres/IResolver.cs
+++ b/Ryujinx.HLE/HOS/Services/Sfdnsres/IResolver.cs
@@ -1,5 +1,11 @@
 using Ryujinx.HLE.HOS.Ipc;
+using System;
 using System.Collections.Generic;
+using System.Net;
+using System.Net.Sockets;
+using System.Text;
+
+using static Ryujinx.HLE.HOS.ErrorCode;
 
 namespace Ryujinx.HLE.HOS.Services.Sfdnsres
 {
@@ -13,8 +19,380 @@ namespace Ryujinx.HLE.HOS.Services.Sfdnsres
         {
             m_Commands = new Dictionary<int, ServiceProcessRequest>()
             {
-                //...
+                { 0,  SetDnsAddressesPrivate },
+                { 1,  GetDnsAddressesPrivate },
+                { 2,  GetHostByName          },
+                { 3,  GetHostByAddress       },
+                { 4,  GetHostStringError     },
+                { 5,  GetGaiStringError      },
+                { 8,  RequestCancelHandle    },
+                { 9,  CancelSocketCall       },
+                { 11, ClearDnsAddresses      },
             };
         }
+
+        private long SerializeHostEnt(ServiceCtx Context, IPHostEntry HostEntry, List<IPAddress> Addresses = null)
+        {
+            long OriginalBufferPosition = Context.Request.ReceiveBuff[0].Position;
+            long BufferPosition         = OriginalBufferPosition;
+            long BufferSize             = Context.Request.ReceiveBuff[0].Size;
+
+            string HostName = HostEntry.HostName + '\0';
+
+            // h_name
+            Context.Memory.WriteBytes(BufferPosition, Encoding.ASCII.GetBytes(HostName));
+            BufferPosition += HostName.Length;
+
+            // h_aliases list size
+            Context.Memory.WriteInt32(BufferPosition, IPAddress.HostToNetworkOrder(HostEntry.Aliases.Length));
+            BufferPosition += 4;
+
+            // Actual aliases
+            foreach (string Alias in HostEntry.Aliases)
+            {
+                Context.Memory.WriteBytes(BufferPosition, Encoding.ASCII.GetBytes(Alias + '\0'));
+                BufferPosition += Alias.Length + 1;
+            }
+
+            // h_addrtype but it's a short (also only support IPv4)
+            Context.Memory.WriteInt16(BufferPosition, IPAddress.HostToNetworkOrder((short)2));
+            BufferPosition += 2;
+
+            // h_length but it's a short
+            Context.Memory.WriteInt16(BufferPosition, IPAddress.HostToNetworkOrder((short)4));
+            BufferPosition += 2;
+
+            // Ip address count, we can only support ipv4 (blame Nintendo)
+            Context.Memory.WriteInt32(BufferPosition, Addresses != null ? IPAddress.HostToNetworkOrder(Addresses.Count) : 0);
+            BufferPosition += 4;
+
+            if (Addresses != null)
+            {
+                foreach (IPAddress Ip in Addresses)
+                {
+                    Context.Memory.WriteInt32(BufferPosition, IPAddress.HostToNetworkOrder(BitConverter.ToInt32(Ip.GetAddressBytes(), 0)));
+                    BufferPosition += 4;
+                }
+            }
+
+            return BufferPosition - OriginalBufferPosition;
+        }
+
+        private string GetGaiStringErrorFromErrorCode(GaiError ErrorCode)
+        {
+            if (ErrorCode > GaiError.Max)
+            {
+                ErrorCode = GaiError.Max;
+            }
+
+            switch (ErrorCode)
+            {
+                case GaiError.AddressFamily:
+                    return "Address family for hostname not supported";
+                case GaiError.Again:
+                    return "Temporary failure in name resolution";
+                case GaiError.BadFlags:
+                    return "Invalid value for ai_flags";
+                case GaiError.Fail:
+                    return "Non-recoverable failure in name resolution";
+                case GaiError.Family:
+                    return "ai_family not supported";
+                case GaiError.Memory:
+                    return "Memory allocation failure";
+                case GaiError.NoData:
+                    return "No address associated with hostname";
+                case GaiError.NoName:
+                    return "hostname nor servname provided, or not known";
+                case GaiError.Service:
+                    return "servname not supported for ai_socktype";
+                case GaiError.SocketType:
+                    return "ai_socktype not supported";
+                case GaiError.System:
+                    return "System error returned in errno";
+                case GaiError.BadHints:
+                    return "Invalid value for hints";
+                case GaiError.Protocol:
+                    return "Resolved protocol is unknown";
+                case GaiError.Overflow:
+                    return "Argument buffer overflow";
+                case GaiError.Max:
+                    return "Unknown error";
+                default:
+                    return "Success";
+            }
+        }
+
+        private string GetHostStringErrorFromErrorCode(NetDBError ErrorCode)
+        {
+            if (ErrorCode <= NetDBError.Internal)
+            {
+                return "Resolver internal error";
+            }
+
+            switch (ErrorCode)
+            {
+                case NetDBError.Success:
+                    return "Resolver Error 0 (no error)";
+                case NetDBError.HostNotFound:
+                    return "Unknown host";
+                case NetDBError.TryAgain:
+                    return "Host name lookup failure";
+                case NetDBError.NoRecovery:
+                    return "Unknown server error";
+                case NetDBError.NoData:
+                    return "No address associated with name";
+                default:
+                    return "Unknown resolver error";
+            }
+        }
+
+        private List<IPAddress> GetIPV4Addresses(IPHostEntry HostEntry)
+        {
+            List<IPAddress> Result = new List<IPAddress>();
+            foreach (IPAddress Ip in HostEntry.AddressList)
+            {
+                if (Ip.AddressFamily == AddressFamily.InterNetwork)
+                    Result.Add(Ip);
+            }
+            return Result;
+        }
+
+        // SetDnsAddressesPrivate(u32, buffer<unknown, 5, 0>)
+        public long SetDnsAddressesPrivate(ServiceCtx Context)
+        {
+            uint Unknown0       = Context.RequestData.ReadUInt32();
+            long BufferPosition = Context.Request.SendBuff[0].Position;
+            long BufferSize     = Context.Request.SendBuff[0].Size;
+
+            // TODO: This is stubbed in 2.0.0+, reverse 1.0.0 version for the sake completeness.
+            Context.Device.Log.PrintStub(Logging.LogClass.ServiceSfdnsres, $"Stubbed. Unknown0: {Unknown0}");
+
+            return MakeError(ErrorModule.Os, 1023);
+        }
+
+        // GetDnsAddressPrivate(u32) -> buffer<unknown, 6, 0>
+        public long GetDnsAddressesPrivate(ServiceCtx Context)
+        {
+            uint Unknown0 = Context.RequestData.ReadUInt32();
+
+            // TODO: This is stubbed in 2.0.0+, reverse 1.0.0 version for the sake completeness.
+            Context.Device.Log.PrintStub(Logging.LogClass.ServiceSfdnsres, $"Stubbed. Unknown0: {Unknown0}");
+
+            return MakeError(ErrorModule.Os, 1023);
+        }
+
+        // GetHostByName(u8, u32, u64, pid, buffer<unknown, 5, 0>) -> (u32, u32, u32, buffer<unknown, 6, 0>)
+        public long GetHostByName(ServiceCtx Context)
+        {
+            byte[] RawName = Context.Memory.ReadBytes(Context.Request.SendBuff[0].Position, Context.Request.SendBuff[0].Size);
+            string Name    = Encoding.ASCII.GetString(RawName).TrimEnd('\0');
+
+            // TODO: use params
+            bool  EnableNsdResolve = Context.RequestData.ReadInt32() == 1;
+            int   TimeOut          = Context.RequestData.ReadInt32();
+            ulong PidPlaceholder   = Context.RequestData.ReadUInt64();
+
+            IPHostEntry HostEntry = null;
+
+            NetDBError NetDBErrorCode = NetDBError.Success;
+            GaiError   Errno          = GaiError.Overflow;
+            long       SerializedSize = 0;
+
+            if (Name.Length <= 255)
+            {
+                try
+                {
+                    HostEntry = Dns.GetHostEntry(Name);
+                }
+                catch (SocketException Exception)
+                {
+                    NetDBErrorCode = NetDBError.Internal;
+
+                    if (Exception.ErrorCode == 11001)
+                    {
+                        NetDBErrorCode = NetDBError.HostNotFound;
+                        Errno = GaiError.NoData;
+                    }
+                    else if (Exception.ErrorCode == 11002)
+                    {
+                        NetDBErrorCode = NetDBError.TryAgain;
+                    }
+                    else if (Exception.ErrorCode == 11003)
+                    {
+                        NetDBErrorCode = NetDBError.NoRecovery;
+                    }
+                    else if (Exception.ErrorCode == 11004)
+                    {
+                        NetDBErrorCode = NetDBError.NoData;
+                    }
+                    else if (Exception.ErrorCode == 10060)
+                    {
+                        Errno = GaiError.Again;
+                    }
+                }
+            }
+            else
+            {
+                NetDBErrorCode = NetDBError.HostNotFound;
+            }
+
+            if (HostEntry != null)
+            {
+                Errno = GaiError.Success;
+
+                List<IPAddress> Addresses = GetIPV4Addresses(HostEntry);
+
+                if (Addresses.Count == 0)
+                {
+                    Errno          = GaiError.NoData;
+                    NetDBErrorCode = NetDBError.NoAddress;
+                }
+                else
+                {
+                    SerializedSize = SerializeHostEnt(Context, HostEntry, Addresses);
+                }
+            }
+
+            Context.ResponseData.Write((int)NetDBErrorCode);
+            Context.ResponseData.Write((int)Errno);
+            Context.ResponseData.Write(SerializedSize);
+
+            return 0;
+        }
+
+        // GetHostByAddr(u32, u32, u32, u64, pid, buffer<unknown, 5, 0>) -> (u32, u32, u32, buffer<unknown, 6, 0>)
+        public long GetHostByAddress(ServiceCtx Context)
+        {
+            byte[] RawIp = Context.Memory.ReadBytes(Context.Request.SendBuff[0].Position, Context.Request.SendBuff[0].Size);
+
+            // TODO: use params
+            uint  SocketLength   = Context.RequestData.ReadUInt32();
+            uint  Type           = Context.RequestData.ReadUInt32();
+            int   TimeOut        = Context.RequestData.ReadInt32();
+            ulong PidPlaceholder = Context.RequestData.ReadUInt64();
+
+            IPHostEntry HostEntry = null;
+
+            NetDBError NetDBErrorCode = NetDBError.Success;
+            GaiError   Errno          = GaiError.AddressFamily;
+            long       SerializedSize = 0;
+
+            if (RawIp.Length == 4)
+            {
+                try
+                {
+                    IPAddress Address = new IPAddress(RawIp);
+
+                    HostEntry = Dns.GetHostEntry(Address);
+                }
+                catch (SocketException Exception)
+                {
+                    NetDBErrorCode = NetDBError.Internal;
+                    if (Exception.ErrorCode == 11001)
+                    {
+                        NetDBErrorCode = NetDBError.HostNotFound;
+                        Errno = GaiError.NoData;
+                    }
+                    else if (Exception.ErrorCode == 11002)
+                    {
+                        NetDBErrorCode = NetDBError.TryAgain;
+                    }
+                    else if (Exception.ErrorCode == 11003)
+                    {
+                        NetDBErrorCode = NetDBError.NoRecovery;
+                    }
+                    else if (Exception.ErrorCode == 11004)
+                    {
+                        NetDBErrorCode = NetDBError.NoData;
+                    }
+                    else if (Exception.ErrorCode == 10060)
+                    {
+                        Errno = GaiError.Again;
+                    }
+                }
+            }
+            else
+            {
+                NetDBErrorCode = NetDBError.NoAddress;
+            }
+
+            if (HostEntry != null)
+            {
+                Errno = GaiError.Success;
+                SerializedSize = SerializeHostEnt(Context, HostEntry, GetIPV4Addresses(HostEntry));
+            }
+
+            Context.ResponseData.Write((int)NetDBErrorCode);
+            Context.ResponseData.Write((int)Errno);
+            Context.ResponseData.Write(SerializedSize);
+
+            return 0;
+        }
+
+        // GetHostStringError(u32) -> buffer<unknown, 6, 0>
+        public long GetHostStringError(ServiceCtx Context)
+        {
+            long       ResultCode  = MakeError(ErrorModule.Os, 1023);
+            NetDBError ErrorCode   = (NetDBError)Context.RequestData.ReadInt32();
+            string     ErrorString = GetHostStringErrorFromErrorCode(ErrorCode);
+
+            if (ErrorString.Length + 1 <= Context.Request.ReceiveBuff[0].Size)
+            {
+                ResultCode = 0;
+                Context.Memory.WriteBytes(Context.Request.ReceiveBuff[0].Position, Encoding.ASCII.GetBytes(ErrorString + '\0'));
+            }
+
+            return ResultCode;
+        }
+
+        // GetGaiStringError(u32) -> buffer<unknown, 6, 0>
+        public long GetGaiStringError(ServiceCtx Context)
+        {
+            long     ResultCode  = MakeError(ErrorModule.Os, 1023);
+            GaiError ErrorCode   = (GaiError)Context.RequestData.ReadInt32();
+            string   ErrorString = GetGaiStringErrorFromErrorCode(ErrorCode);
+
+            if (ErrorString.Length + 1 <= Context.Request.ReceiveBuff[0].Size)
+            {
+                ResultCode = 0;
+                Context.Memory.WriteBytes(Context.Request.ReceiveBuff[0].Position, Encoding.ASCII.GetBytes(ErrorString + '\0'));
+            }
+
+            return ResultCode;
+        }
+
+        // RequestCancelHandle(u64, pid) -> u32
+        public long RequestCancelHandle(ServiceCtx Context)
+        {
+            ulong Unknown0 = Context.RequestData.ReadUInt64();
+
+            Context.ResponseData.Write(0);
+
+            Context.Device.Log.PrintStub(Logging.LogClass.ServiceSfdnsres, $"Stubbed. Unknown0: {Unknown0}");
+
+            return 0;
+        }
+
+        // CancelSocketCall(u32, u64, pid)
+        public long CancelSocketCall(ServiceCtx Context)
+        {
+            uint  Unknown0 = Context.RequestData.ReadUInt32();
+            ulong Unknown1 = Context.RequestData.ReadUInt64();
+
+            Context.Device.Log.PrintStub(Logging.LogClass.ServiceSfdnsres, $"Stubbed. Unknown0: {Unknown0} - " +
+                                                                           $"Unknown1: {Unknown1}");
+
+            return 0;
+        }
+
+        // ClearDnsAddresses(u32)
+        public long ClearDnsAddresses(ServiceCtx Context)
+        {
+            uint Unknown0 = Context.RequestData.ReadUInt32();
+
+            Context.Device.Log.PrintStub(Logging.LogClass.ServiceSfdnsres, $"Stubbed. Unknown0: {Unknown0}");
+
+            return 0;
+        }
     }
 }
diff --git a/Ryujinx.HLE/HOS/Services/Sfdnsres/NetDBError.cs b/Ryujinx.HLE/HOS/Services/Sfdnsres/NetDBError.cs
new file mode 100644
index 00000000..6c1b7825
--- /dev/null
+++ b/Ryujinx.HLE/HOS/Services/Sfdnsres/NetDBError.cs
@@ -0,0 +1,13 @@
+namespace Ryujinx.HLE.HOS.Services.Sfdnsres
+{
+    enum NetDBError
+    {
+        Internal = -1,
+        Success,
+        HostNotFound,
+        TryAgain,
+        NoRecovery,
+        NoData,
+        NoAddress = NoData,
+    }
+}