Audio and voice client support

Wumpus.Net.sln

@@ -32,6 +32,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Wumpus.Net.Tests.Server", "
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Wumpus.Net.Bot", "src\Wumpus.Net.Bot\Wumpus.Net.Bot.csproj", "{ED977313-7BC8-4A5E-8A24-1BF42635D293}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Wumpus.Net.Audio", "src\Wumpus.Net.Audio\Wumpus.Net.Audio.csproj", "{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -150,6 +152,18 @@ Global
 		{ED977313-7BC8-4A5E-8A24-1BF42635D293}.Release|x64.Build.0 = Release|Any CPU
 		{ED977313-7BC8-4A5E-8A24-1BF42635D293}.Release|x86.ActiveCfg = Release|Any CPU
 		{ED977313-7BC8-4A5E-8A24-1BF42635D293}.Release|x86.Build.0 = Release|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Debug|x64.Build.0 = Debug|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Debug|x86.Build.0 = Debug|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Release|x64.ActiveCfg = Release|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Release|x64.Build.0 = Release|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Release|x86.ActiveCfg = Release|Any CPU
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -164,6 +178,7 @@ Global
 		{0967FF88-E435-4132-9524-B252A3D9BCD6} = {9806905E-1B09-4AC2-BF4F-731C9E473F94}
 		{C6BE9630-1E1F-4DD1-9205-045A50181AA7} = {9806905E-1B09-4AC2-BF4F-731C9E473F94}
 		{ED977313-7BC8-4A5E-8A24-1BF42635D293} = {F7B9BFB1-C836-4432-BE64-719A38E0BBEF}
+		{5ABF3E1B-45E9-4CA7-A455-8923C54B480F} = {F7B9BFB1-C836-4432-BE64-719A38E0BBEF}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {B5B02039-F4C2-44C6-91B8-340E44472AED}

src/Wumpus.Net.Audio/Events/VoiceHelloEvent.cs

@@ -0,0 +1,15 @@
+using Voltaic.Serialization;
+
+namespace Wumpus.Events
+{
+    public class VoiceHelloEvent
+    {
+        // Given as float because discord returns json of the form
+        // {"op":8,"d":{"v":4,"heartbeat_interval":13750.0}}
+        [ModelProperty("heartbeat_interval")]
+        public float HeartbeatInterval { get; set; }
+
+        [ModelProperty("v")]
+        public int GatewayVersion { get; set; }
+    }
+}

src/Wumpus.Net.Audio/Events/VoiceReadyEvent.cs

@@ -0,0 +1,20 @@
+using Voltaic;
+using Voltaic.Serialization;
+
+namespace Wumpus.Events
+{
+    public class VoiceReadyEvent
+    {
+        [ModelProperty("ssrc")]
+        public uint Ssrc { get; set; }
+
+        [ModelProperty("port")]
+        public int Port { get; set; }
+
+        [ModelProperty("modes")]
+        public Utf8String[] EncryptionSchemes { get; set; }
+
+        [ModelProperty("ip")]
+        public Utf8String IpAddress { get; set; }
+    }
+}

src/Wumpus.Net.Audio/Events/VoiceSessionDescriptionEvent.cs

@@ -0,0 +1,23 @@
+using Voltaic;
+using Voltaic.Serialization;
+
+namespace Wumpus.Events
+{
+    public class VoiceSessionDescriptionEvent
+    {
+        [ModelProperty("video_codec")]
+        public Utf8String VideoCodec { get; set; }
+
+        [ModelProperty("secret_key")]
+        public byte[] SecretKey { get; set; }
+
+        [ModelProperty("mode")]
+        public Utf8String EncryptionScheme { get; set; }
+
+        [ModelProperty("media_session_id")]
+        public Utf8String VideoSessionId { get; set; }
+
+        [ModelProperty("audio_codec")]
+        public Utf8String AudioCodec { get; set; }
+    }
+}

src/Wumpus.Net.Audio/IPUtilities.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Net;
+using Voltaic.Serialization.Utf8;
+
+namespace Wumpus
+{
+    public static class IPUtilities
+    {
+        public static bool TryParseIPv4Address(ReadOnlySpan<byte> buffer, out IPAddress address)
+            => TryParseIPv4Address(ref buffer, out address);
+
+        public static bool TryParseIPv4Address(ref ReadOnlySpan<byte> buffer, out IPAddress address)
+        {
+            address = default;
+            ulong value = 0;
+
+            for (int i = 0; i < 4; i++)
+            {
+                if (!Utf8Reader.TryReadUInt8(ref buffer, out byte section, 'g'))
+                    return false;
+
+                value |= (ulong)section << (i * 8);
+
+                // last value does not have a dot following it
+                if (i != 3)
+                {
+                    if (buffer[0] != '.')
+                        return false;
+
+                    buffer = buffer.Slice(1);
+                }
+            }
+
+            address = new IPAddress((long)value);
+            return true;
+        }
+    }
+}

src/Wumpus.Net.Audio/Requests/VoiceIdentifyParams.cs

@@ -0,0 +1,20 @@
+using Voltaic;
+using Voltaic.Serialization;
+
+namespace Wumpus.Requests
+{
+    public class VoiceIdentifyParams
+    {
+        [ModelProperty("user_id")]
+        public Snowflake UserId { get; set; }
+
+        [ModelProperty("server_id")]
+        public Snowflake GuildId { get; set; }
+
+        [ModelProperty("session_id")]
+        public Utf8String SessionId { get; set; }
+
+        [ModelProperty("token")]
+        public Utf8String Token { get; set; }
+    }
+}

src/Wumpus.Net.Audio/Requests/VoiceResumeParams.cs

@@ -0,0 +1,17 @@
+using Voltaic;
+using Voltaic.Serialization;
+
+namespace Wumpus.Requests
+{
+    public class VoiceResumeParams
+    {
+        [ModelProperty("server_id")]
+        public Snowflake GuildId { get; set; }
+
+        [ModelProperty("session_id")]
+        public Utf8String SessionId { get; set; }
+
+        [ModelProperty("token")]
+        public Utf8String Token { get; set; }
+    }
+}

src/Wumpus.Net.Audio/Requests/VoiceSelectProtocolParams.cs

@@ -0,0 +1,26 @@
+using Voltaic;
+using Voltaic.Serialization;
+
+namespace Wumpus.Requests
+{
+    public class VoiceSelectProtocolParams
+    {
+        [ModelProperty("protocol")]
+        public Utf8String TransportProtocol { get; set; }
+
+        [ModelProperty("data")]
+        public VoiceSelectProtocolConnectionProperties Properties { get; set; }
+    }
+
+    public class VoiceSelectProtocolConnectionProperties
+    {
+        [ModelProperty("ip")]
+        public Utf8String Ip { get; set; }
+
+        [ModelProperty("port")]
+        public int Port { get; set; }
+
+        [ModelProperty("mode")]
+        public Utf8String EncryptionScheme { get; set; }
+    }
+}

src/Wumpus.Net.Audio/Requests/VoiceSpeakingParams.cs

@@ -0,0 +1,16 @@
+using Voltaic.Serialization;
+
+namespace Wumpus.Requests
+{
+    public class VoiceSpeakingParams
+    {
+        [ModelProperty("speaking")]
+        public int Speaking { get; set; }
+
+        [ModelProperty("delay")]
+        public uint DelayMilliseconds { get; set; }
+
+        [ModelProperty("ssrc")]
+        public uint Ssrc { get; set; }
+    }
+}

src/Wumpus.Net.Audio/Sodium/SodiumPrimitives.cs

@@ -0,0 +1,55 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace Wumpus
+{
+    internal class SodiumPrimitives
+    {
+        // sodium.dll on windows, libsodium.so on linux
+        [DllImport("sodium")]
+        extern static int crypto_secretbox_macbytes();
+        [DllImport("sodium")]
+        extern static int crypto_secretbox_keybytes();
+        [DllImport("sodium")]
+        extern static int crypto_secretbox_noncebytes();
+
+        [DllImport("sodium")]
+        extern static int crypto_secretbox_easy(ref byte c, in byte m, int mlen, in byte n, in byte k);
+        [DllImport("sodium")]
+        extern static int crypto_secretbox_open_easy(ref byte m, in byte c, int clen, in byte n, in byte k);
+
+        [DllImport("sodium")]
+        extern static void randombytes_buf(ref byte buf, int size);
+
+        // use the functions to grab the info so it's not hardcoded in the lib
+        private static readonly int MACBYTES = crypto_secretbox_macbytes();
+        private static readonly int KEYBYTES = crypto_secretbox_keybytes();
+        private static readonly int NONCEBYTES = crypto_secretbox_noncebytes();
+
+        public static int NonceSize => NONCEBYTES;
+
+        public static int ComputeMessageLength(int messageLength)
+            => messageLength + MACBYTES;
+
+        public static bool TryEncryptInPlace(Span<byte> ciphertext, ReadOnlySpan<byte> message, ReadOnlySpan<byte> nonce, ReadOnlySpan<byte> secret)
+        {
+            if (ciphertext.Length < message.Length + MACBYTES)
+                return false;
+            if (secret.Length < KEYBYTES)
+                return false;
+            if (nonce.Length < NONCEBYTES)
+                return false;
+
+            return crypto_secretbox_easy(
+                ref ciphertext.GetPinnableReference(),
+                message.GetPinnableReference(), message.Length,
+                nonce.GetPinnableReference(),
+                secret.GetPinnableReference()) == 0;
+        }
+
+        public static void GenerateRandomBytes(Span<byte> buffer)
+        {
+            randombytes_buf(ref buffer.GetPinnableReference(), buffer.Length);
+        }
+    }
+}

src/Wumpus.Net.Audio/SpeakingState.cs

@@ -0,0 +1,15 @@
+using System;
+
+namespace Wumpus
+{
+    [Flags]
+    public enum SpeakingState : byte
+    {
+        NotSpeaking = 0b0,
+        Speaking = 0b1,
+
+        Priority = 0b100,
+
+        PrioritySpeaking = Speaking | Priority
+    }
+}

src/Wumpus.Net.Audio/VoiceGatewayOperation.cs

@@ -0,0 +1,41 @@
+namespace Wumpus.Events
+{
+    /// <summary>
+    ///     Voice connections operate in a similar fashion to the Gateway connection.
+    ///     However, they use a different set of payloads and a separate UDP-based connection for voice data transmission.
+    ///     https://discordapp.com/developers/docs/topics/voice-connections#voice
+    /// </summary>
+    public enum VoiceGatewayOperation : byte
+    {
+        /// <summary> C→S - Used to begin a voice websocket connection. </summary>
+        Identify = 0,
+        /// <summary> C→S - Used to select the voice protocol. </summary>
+        SelectProtocol = 1,
+        /// <summary> C←S - Used to complete the websocket handshake. </summary>
+        Ready = 2,
+        /// <summary> C→S - Used to keep the websocket connection alive. </summary>
+        Heartbeat = 3,
+        /// <summary> C→S - Used to describe the session. </summary>
+        SessionDescription = 4,
+        /// <summary> C↔S - Used to indicate which users are speaking. </summary>
+        Speaking = 5,
+        /// <summary> C←S - Used to reply to a heartbeat. </summary>
+        HeartbeatAck = 6,
+        /// <summary> C→S - Used to resume a connection. </summary>
+        Resume = 7,
+        /// <summary> C→S - Used to begin the websocket handshake. </summary>
+        Hello = 8,
+        /// <summary> C←S - Used to complete the websocket handshake with an existing session. </summary>
+        Resumed = 9
+
+        //NOTE: these do not have official names!
+        //They are documented here for future expansion purposes
+
+        //ssrc update, occurs when a user connects or changes screenshare settings
+        //SsrcUpdate = 12,
+        //user disconnected, occurs when a user disconnects
+        //UserDisconnected = 13,
+        //change channel, occurs whenever the client gets moved into another channel
+        //ChangeChannel = 14
+    }
+}

src/Wumpus.Net.Audio/VoiceGatewayPayload.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+using Voltaic.Serialization;
+using Wumpus.Entities;
+using Wumpus.Requests;
+
+namespace Wumpus.Events
+{
+    public class VoiceGatewayPayload
+    {
+        [ModelProperty("op")]
+        public VoiceGatewayOperation Operation { get; set; }
+
+        [ModelProperty("d")]
+        [ModelTypeSelector(nameof(Operation), nameof(OpCodeTypeSelector))]
+        public object Data { get; set; }
+
+        private static Dictionary<VoiceGatewayOperation, Type> OpCodeTypeSelector => new Dictionary<VoiceGatewayOperation, Type>()
+        {
+            [VoiceGatewayOperation.Hello] = typeof(VoiceHelloEvent),
+            [VoiceGatewayOperation.Ready] = typeof(VoiceReadyEvent),
+            [VoiceGatewayOperation.HeartbeatAck] = typeof(int),
+
+            [VoiceGatewayOperation.Identify] = typeof(VoiceIdentifyParams),
+            [VoiceGatewayOperation.SelectProtocol] = typeof(VoiceSelectProtocolParams),
+            [VoiceGatewayOperation.SessionDescription] = typeof(VoiceSessionDescriptionEvent),
+            [VoiceGatewayOperation.Resume] = typeof(VoiceResumeParams),
+            [VoiceGatewayOperation.Heartbeat] = typeof(int),
+
+            [VoiceGatewayOperation.Speaking] = typeof(VoiceSpeakingParams),
+        };
+    }
+}

src/Wumpus.Net.Audio/Wumpus.Net.Audio.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <Import Project="../Wumpus.Net.targets" />
+  <PropertyGroup>
+    <RootNamespace>Wumpus</RootNamespace>
+    <AssemblyName>Wumpus.Net.Audio</AssemblyName>
+    <PackageTags>discord;discordapp;wumpus;audio;websocket;api;rogueexception</PackageTags>
+    <Description>Provides a low-level audio client for the Discord API</Description>
+    <TargetFrameworks>netstandard2.0</TargetFrameworks>
+  </PropertyGroup>
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Net.Compilers.Toolset" Version="3.1.0">
+      <PrivateAssets>all</PrivateAssets>
+    </PackageReference>
+    <PackageReference Include="System.Net.WebSockets.Client" Version="4.3.1" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="../Wumpus.Net.Core/Wumpus.Net.Core.csproj" />
+  </ItemGroup>
+</Project>