chat: add database types and auth middleware

.idea/.idea.Foxchat/.idea/.gitignore

@@ -0,0 +1,13 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Rider ignored files
+/.idea.Foxchat.iml
+/contentModel.xml
+/modules.xml
+/projectSettingsUpdater.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml

.idea/.idea.Foxchat/.idea/.name

@@ -0,0 +1 @@
+Foxchat

.idea/.idea.Foxchat/.idea/encodings.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding" addBOMForNewFiles="with BOM under Windows, with no BOM otherwise" />
+</project>

.idea/.idea.Foxchat/.idea/indexLayout.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="UserContentModel">
+    <attachedFolders />
+    <explicitIncludes />
+    <explicitExcludes />
+  </component>
+</project>

.idea/.idea.Foxchat/.idea/sqldialects.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="SqlDialectMappings">
+    <file url="file://$PROJECT_DIR$/Foxchat.Chat/Migrations/20240521132416_Init.cs" dialect="PostgreSQL" />
+    <file url="PROJECT" dialect="PostgreSQL" />
+  </component>
+</project>

.idea/.idea.Foxchat/.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>

Foxchat.Chat/Database/BaseModel.cs

@@ -0,0 +1,6 @@
+namespace Foxchat.Chat.Database;
+
+public abstract class BaseModel
+{
+    public Ulid Id { get; init; } = Ulid.NewUlid();
+}

Foxchat.Chat/Database/ChatContext.cs

@@ -1,3 +1,4 @@
+using Foxchat.Chat.Database.Models;
 using Foxchat.Core;
 using Foxchat.Core.Database;
 using Microsoft.EntityFrameworkCore;
@@ -11,6 +12,11 @@ public class ChatContext : IDatabaseContext
     private readonly NpgsqlDataSource _dataSource;
 
     public override DbSet<Instance> Instance { get; set; }
+    public DbSet<IdentityInstance> IdentityInstances { get; set; }
+    public DbSet<User> Users { get; set; }
+    public DbSet<Guild> Guilds { get; set; }
+    public DbSet<Channel> Channels { get; set; }
+    public DbSet<Message> Messages { get; set; }
 
     public ChatContext(InstanceConfig config)
     {
@@ -38,16 +44,31 @@ public class ChatContext : IDatabaseContext
 
     protected override void OnModelCreating(ModelBuilder modelBuilder)
     {
+        modelBuilder.Entity<IdentityInstance>().HasIndex(i => i.Domain).IsUnique();
+
+        modelBuilder.Entity<User>().HasIndex(u => new { u.RemoteUserId, u.InstanceId }).IsUnique();
+        modelBuilder.Entity<User>().HasIndex(u => new { u.Username, u.InstanceId }).IsUnique();
+
+        modelBuilder.Entity<Guild>()
+            .HasOne(e => e.Owner)
+            .WithMany(e => e.OwnedGuilds)
+            .HasForeignKey(e => e.OwnerId)
+            .IsRequired();
+
+        modelBuilder.Entity<User>()
+            .HasMany(e => e.Guilds)
+            .WithMany(e => e.Users);
     }
 }
 
+// ReSharper disable once UnusedType.Global
 public class DesignTimeIdentityContextFactory : IDesignTimeDbContextFactory<ChatContext>
 {
     public ChatContext CreateDbContext(string[] args)
     {
         // Read the configuration file
         var config = new ConfigurationBuilder()
-            .AddConfiguration("identity.ini")
+            .AddConfiguration("chat.ini")
             .Build()
             // Get the configuration as our config class
             .Get<InstanceConfig>() ?? new();

Foxchat.Chat/Database/Models/Channel.cs

@@ -0,0 +1,9 @@
+namespace Foxchat.Chat.Database.Models;
+
+public class Channel : BaseModel
+{
+    public Ulid GuildId { get; init; }
+    public Guild Guild { get; init; } = null!;
+    public string Name { get; set; } = null!;
+    public string? Topic { get; set; }
+}

Foxchat.Chat/Database/Models/Guild.cs

@@ -0,0 +1,11 @@
+namespace Foxchat.Chat.Database.Models;
+
+public class Guild : BaseModel
+{
+    public string Name { get; set; } = null!;
+    public Ulid OwnerId { get; set; }
+    public User Owner { get; set; } = null!;
+
+    public List<User> Users { get; } = [];
+    public List<Channel> Channels { get; } = [];
+}

Foxchat.Chat/Database/Models/IdentityInstance.cs

@@ -0,0 +1,17 @@
+namespace Foxchat.Chat.Database.Models;
+
+public class IdentityInstance : BaseModel
+{
+    public string Domain { get; init; } = null!;
+    public string BaseUrl { get; init; } = null!;
+    public string PublicKey { get; init; } = null!;
+
+    public InstanceStatus Status { get; set; } = InstanceStatus.Active;
+    public string? Reason { get; set; }
+
+    public enum InstanceStatus
+    {
+        Active,
+        Suspended,
+    }
+}

Foxchat.Chat/Database/Models/Message.cs

@@ -0,0 +1,15 @@
+using NodaTime;
+
+namespace Foxchat.Chat.Database.Models;
+
+public class Message : BaseModel
+{
+    public Ulid ChannelId { get; init; }
+    public Channel Channel { get; init; } = null!;
+    public Ulid AuthorId { get; init; }
+    public User Author { get; init; } = null!;
+    
+    public string? Content { get; set; }
+    
+    public Instant? UpdatedAt { get; set; }
+}

Foxchat.Chat/Database/Models/User.cs

@@ -0,0 +1,14 @@
+namespace Foxchat.Chat.Database.Models;
+
+public class User : BaseModel
+{
+    public Ulid InstanceId { get; init; }
+    public IdentityInstance Instance { get; init; } = null!;
+    public string RemoteUserId { get; init; } = null!;
+    public string Username { get; init; } = null!;
+
+    public string? Avatar { get; set; }
+
+    public List<Guild> Guilds { get; } = [];
+    public List<Guild> OwnedGuilds { get; } = [];
+}

Foxchat.Chat/Extensions/WebApplicationExtensions.cs

@@ -0,0 +1,18 @@
+using Foxchat.Chat.Middleware;
+
+namespace Foxchat.Chat.Extensions;
+
+public static class WebApplicationExtensions
+{
+    public static IServiceCollection AddCustomMiddleware(this IServiceCollection services)
+    {
+        return services
+            .AddScoped<AuthenticationMiddleware>();
+    }
+
+    public static IApplicationBuilder UseCustomMiddleware(this IApplicationBuilder app)
+    {
+        return app
+            .UseMiddleware<AuthenticationMiddleware>();
+    }
+}

Foxchat.Chat/Middleware/AuthenticationMiddleware.cs

@@ -0,0 +1,106 @@
+using Foxchat.Chat.Database;
+using Foxchat.Chat.Database.Models;
+using Foxchat.Core;
+using Foxchat.Core.Federation;
+using Microsoft.EntityFrameworkCore;
+
+namespace Foxchat.Chat.Middleware;
+
+public class AuthenticationMiddleware(ILogger logger, ChatContext db, RequestSigningService requestSigningService)
+    : IMiddleware
+{
+    public async Task InvokeAsync(HttpContext ctx, RequestDelegate next)
+    {
+        var endpoint = ctx.GetEndpoint();
+        // Endpoints require server authentication by default, unless they have the [Unauthenticated] attribute.
+        var metadata = endpoint?.Metadata.GetMetadata<UnauthenticatedAttribute>();
+        if (metadata != null)
+        {
+            await next(ctx);
+            return;
+        }
+
+        if (!ExtractRequestData(ctx, out var signature, out var domain, out var signatureData))
+            throw new ApiError.IncomingFederationError("This endpoint requires signed requests.");
+
+        var instance = await GetInstanceAsync(domain);
+
+        if (!requestSigningService.VerifySignature(instance.PublicKey, signature, signatureData))
+            throw new ApiError.IncomingFederationError("Signature is not valid.");
+        
+        ctx.SetSignature(instance, signatureData);
+
+        await next(ctx);
+    }
+
+    private async Task<IdentityInstance> GetInstanceAsync(string domain)
+    {
+        return await db.IdentityInstances.FirstOrDefaultAsync(i => i.Domain == domain)
+               ?? throw new ApiError.IncomingFederationError("Remote instance is not known.");
+    }
+
+    private bool ExtractRequestData(HttpContext ctx, out string signature, out string domain, out SignatureData data)
+    {
+        signature = string.Empty;
+        domain = string.Empty;
+        data = SignatureData.Empty;
+
+        if (!ctx.Request.Headers.TryGetValue(RequestSigningService.SIGNATURE_HEADER, out var encodedSignature))
+            return false;
+        if (!ctx.Request.Headers.TryGetValue(RequestSigningService.DATE_HEADER, out var date))
+            return false;
+        if (!ctx.Request.Headers.TryGetValue(RequestSigningService.SERVER_HEADER, out var server))
+            return false;
+        var time = RequestSigningService.ParseTime(date.ToString());
+        string? userId = null;
+        if (ctx.Request.Headers.TryGetValue(RequestSigningService.USER_HEADER, out var userIdHeader))
+            userId = userIdHeader;
+        var host = ctx.Request.Headers.Host.ToString();
+
+        signature = encodedSignature.ToString();
+        domain = server.ToString();
+        data = new SignatureData(
+            time,
+            host,
+            ctx.Request.Path,
+            (int?)ctx.Request.Headers.ContentLength,
+            userId
+        );
+
+        return true;
+    }
+}
+
+[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
+public class UnauthenticatedAttribute : Attribute;
+
+public static class HttpContextExtensions
+{
+    private const string Key = "instance";
+
+    public static void SetSignature(this HttpContext ctx, IdentityInstance instance, SignatureData data)
+    {
+        ctx.Items.Add(Key, (instance, data));
+    }
+
+    public static (IdentityInstance?, SignatureData?) GetSignature(this HttpContext ctx)
+    {
+        try
+        {
+            var obj = ctx.GetSignatureOrThrow();
+            return (obj.Item1, obj.Item2);
+        }
+        catch
+        {
+            return (null, null);
+        }
+    }
+
+    public static (IdentityInstance, SignatureData) GetSignatureOrThrow(this HttpContext ctx)
+    {
+        if (!ctx.Items.TryGetValue(Key, out var obj))
+            throw new ApiError.AuthenticationError("No instance in HttpContext");
+
+        return ((IdentityInstance, SignatureData))obj!;
+    }
+}

Foxchat.Chat/Migrations/20240521132416_Init.Designer.cs

@@ -0,0 +1,325 @@
+// <auto-generated />
+using System;
+using Foxchat.Chat.Database;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using NodaTime;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace Foxchat.Chat.Migrations
+{
+    [DbContext(typeof(ChatContext))]
+    [Migration("20240521132416_Init")]
+    partial class Init
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "8.0.5")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Channel", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<Guid>("GuildId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("guild_id");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("name");
+
+                    b.Property<string>("Topic")
+                        .HasColumnType("text")
+                        .HasColumnName("topic");
+
+                    b.HasKey("Id")
+                        .HasName("pk_channels");
+
+                    b.HasIndex("GuildId")
+                        .HasDatabaseName("ix_channels_guild_id");
+
+                    b.ToTable("channels", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Guild", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("name");
+
+                    b.Property<Guid>("OwnerId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("owner_id");
+
+                    b.HasKey("Id")
+                        .HasName("pk_guilds");
+
+                    b.HasIndex("OwnerId")
+                        .HasDatabaseName("ix_guilds_owner_id");
+
+                    b.ToTable("guilds", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.IdentityInstance", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<string>("BaseUrl")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("base_url");
+
+                    b.Property<string>("Domain")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("domain");
+
+                    b.Property<string>("PublicKey")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("public_key");
+
+                    b.Property<string>("Reason")
+                        .HasColumnType("text")
+                        .HasColumnName("reason");
+
+                    b.Property<int>("Status")
+                        .HasColumnType("integer")
+                        .HasColumnName("status");
+
+                    b.HasKey("Id")
+                        .HasName("pk_identity_instances");
+
+                    b.HasIndex("Domain")
+                        .IsUnique()
+                        .HasDatabaseName("ix_identity_instances_domain");
+
+                    b.ToTable("identity_instances", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Message", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<Guid>("AuthorId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("author_id");
+
+                    b.Property<Guid>("ChannelId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("channel_id");
+
+                    b.Property<string>("Content")
+                        .HasColumnType("text")
+                        .HasColumnName("content");
+
+                    b.Property<Instant?>("UpdatedAt")
+                        .HasColumnType("timestamp with time zone")
+                        .HasColumnName("updated_at");
+
+                    b.HasKey("Id")
+                        .HasName("pk_messages");
+
+                    b.HasIndex("AuthorId")
+                        .HasDatabaseName("ix_messages_author_id");
+
+                    b.HasIndex("ChannelId")
+                        .HasDatabaseName("ix_messages_channel_id");
+
+                    b.ToTable("messages", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.User", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<string>("Avatar")
+                        .HasColumnType("text")
+                        .HasColumnName("avatar");
+
+                    b.Property<Guid>("InstanceId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("instance_id");
+
+                    b.Property<string>("RemoteUserId")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("remote_user_id");
+
+                    b.Property<string>("Username")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("username");
+
+                    b.HasKey("Id")
+                        .HasName("pk_users");
+
+                    b.HasIndex("InstanceId")
+                        .HasDatabaseName("ix_users_instance_id");
+
+                    b.HasIndex("RemoteUserId", "InstanceId")
+                        .IsUnique()
+                        .HasDatabaseName("ix_users_remote_user_id_instance_id");
+
+                    b.HasIndex("Username", "InstanceId")
+                        .IsUnique()
+                        .HasDatabaseName("ix_users_username_instance_id");
+
+                    b.ToTable("users", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Core.Database.Instance", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("id");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
+
+                    b.Property<string>("PrivateKey")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("private_key");
+
+                    b.Property<string>("PublicKey")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("public_key");
+
+                    b.HasKey("Id")
+                        .HasName("pk_instance");
+
+                    b.ToTable("instance", (string)null);
+                });
+
+            modelBuilder.Entity("GuildUser", b =>
+                {
+                    b.Property<Guid>("GuildsId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("guilds_id");
+
+                    b.Property<Guid>("UsersId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("users_id");
+
+                    b.HasKey("GuildsId", "UsersId")
+                        .HasName("pk_guild_user");
+
+                    b.HasIndex("UsersId")
+                        .HasDatabaseName("ix_guild_user_users_id");
+
+                    b.ToTable("guild_user", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Channel", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.Guild", "Guild")
+                        .WithMany("Channels")
+                        .HasForeignKey("GuildId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_channels_guilds_guild_id");
+
+                    b.Navigation("Guild");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Guild", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.User", "Owner")
+                        .WithMany("OwnedGuilds")
+                        .HasForeignKey("OwnerId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_guilds_users_owner_id");
+
+                    b.Navigation("Owner");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Message", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.User", "Author")
+                        .WithMany()
+                        .HasForeignKey("AuthorId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_messages_users_author_id");
+
+                    b.HasOne("Foxchat.Chat.Database.Models.Channel", "Channel")
+                        .WithMany()
+                        .HasForeignKey("ChannelId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_messages_channels_channel_id");
+
+                    b.Navigation("Author");
+
+                    b.Navigation("Channel");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.User", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.IdentityInstance", "Instance")
+                        .WithMany()
+                        .HasForeignKey("InstanceId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_users_identity_instances_instance_id");
+
+                    b.Navigation("Instance");
+                });
+
+            modelBuilder.Entity("GuildUser", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.Guild", null)
+                        .WithMany()
+                        .HasForeignKey("GuildsId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_guild_user_guilds_guilds_id");
+
+                    b.HasOne("Foxchat.Chat.Database.Models.User", null)
+                        .WithMany()
+                        .HasForeignKey("UsersId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_guild_user_users_users_id");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Guild", b =>
+                {
+                    b.Navigation("Channels");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.User", b =>
+                {
+                    b.Navigation("OwnedGuilds");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Foxchat.Chat/Migrations/20240521132416_Init.cs

@@ -0,0 +1,228 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using NodaTime;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace Foxchat.Chat.Migrations
+{
+    /// <inheritdoc />
+    public partial class Init : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "identity_instances",
+                columns: table => new
+                {
+                    id = table.Column<Guid>(type: "uuid", nullable: false),
+                    domain = table.Column<string>(type: "text", nullable: false),
+                    base_url = table.Column<string>(type: "text", nullable: false),
+                    public_key = table.Column<string>(type: "text", nullable: false),
+                    status = table.Column<int>(type: "integer", nullable: false),
+                    reason = table.Column<string>(type: "text", nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_identity_instances", x => x.id);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "instance",
+                columns: table => new
+                {
+                    id = table.Column<int>(type: "integer", nullable: false)
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    public_key = table.Column<string>(type: "text", nullable: false),
+                    private_key = table.Column<string>(type: "text", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_instance", x => x.id);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "users",
+                columns: table => new
+                {
+                    id = table.Column<Guid>(type: "uuid", nullable: false),
+                    instance_id = table.Column<Guid>(type: "uuid", nullable: false),
+                    remote_user_id = table.Column<string>(type: "text", nullable: false),
+                    username = table.Column<string>(type: "text", nullable: false),
+                    avatar = table.Column<string>(type: "text", nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_users", x => x.id);
+                    table.ForeignKey(
+                        name: "fk_users_identity_instances_instance_id",
+                        column: x => x.instance_id,
+                        principalTable: "identity_instances",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "guilds",
+                columns: table => new
+                {
+                    id = table.Column<Guid>(type: "uuid", nullable: false),
+                    name = table.Column<string>(type: "text", nullable: false),
+                    owner_id = table.Column<Guid>(type: "uuid", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_guilds", x => x.id);
+                    table.ForeignKey(
+                        name: "fk_guilds_users_owner_id",
+                        column: x => x.owner_id,
+                        principalTable: "users",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "channels",
+                columns: table => new
+                {
+                    id = table.Column<Guid>(type: "uuid", nullable: false),
+                    guild_id = table.Column<Guid>(type: "uuid", nullable: false),
+                    name = table.Column<string>(type: "text", nullable: false),
+                    topic = table.Column<string>(type: "text", nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_channels", x => x.id);
+                    table.ForeignKey(
+                        name: "fk_channels_guilds_guild_id",
+                        column: x => x.guild_id,
+                        principalTable: "guilds",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "guild_user",
+                columns: table => new
+                {
+                    guilds_id = table.Column<Guid>(type: "uuid", nullable: false),
+                    users_id = table.Column<Guid>(type: "uuid", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_guild_user", x => new { x.guilds_id, x.users_id });
+                    table.ForeignKey(
+                        name: "fk_guild_user_guilds_guilds_id",
+                        column: x => x.guilds_id,
+                        principalTable: "guilds",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                    table.ForeignKey(
+                        name: "fk_guild_user_users_users_id",
+                        column: x => x.users_id,
+                        principalTable: "users",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateTable(
+                name: "messages",
+                columns: table => new
+                {
+                    id = table.Column<Guid>(type: "uuid", nullable: false),
+                    channel_id = table.Column<Guid>(type: "uuid", nullable: false),
+                    author_id = table.Column<Guid>(type: "uuid", nullable: false),
+                    content = table.Column<string>(type: "text", nullable: true),
+                    updated_at = table.Column<Instant>(type: "timestamp with time zone", nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("pk_messages", x => x.id);
+                    table.ForeignKey(
+                        name: "fk_messages_channels_channel_id",
+                        column: x => x.channel_id,
+                        principalTable: "channels",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                    table.ForeignKey(
+                        name: "fk_messages_users_author_id",
+                        column: x => x.author_id,
+                        principalTable: "users",
+                        principalColumn: "id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "ix_channels_guild_id",
+                table: "channels",
+                column: "guild_id");
+
+            migrationBuilder.CreateIndex(
+                name: "ix_guild_user_users_id",
+                table: "guild_user",
+                column: "users_id");
+
+            migrationBuilder.CreateIndex(
+                name: "ix_guilds_owner_id",
+                table: "guilds",
+                column: "owner_id");
+
+            migrationBuilder.CreateIndex(
+                name: "ix_identity_instances_domain",
+                table: "identity_instances",
+                column: "domain",
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "ix_messages_author_id",
+                table: "messages",
+                column: "author_id");
+
+            migrationBuilder.CreateIndex(
+                name: "ix_messages_channel_id",
+                table: "messages",
+                column: "channel_id");
+
+            migrationBuilder.CreateIndex(
+                name: "ix_users_instance_id",
+                table: "users",
+                column: "instance_id");
+
+            migrationBuilder.CreateIndex(
+                name: "ix_users_remote_user_id_instance_id",
+                table: "users",
+                columns: new[] { "remote_user_id", "instance_id" },
+                unique: true);
+
+            // EF Core doesn't support creating indexes on arbitrary expressions, so we have to create it manually.
+            migrationBuilder.Sql("CREATE UNIQUE INDEX ix_users_username_instance_id ON users (lower(username), instance_id)");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "guild_user");
+
+            migrationBuilder.DropTable(
+                name: "instance");
+
+            migrationBuilder.DropTable(
+                name: "messages");
+
+            migrationBuilder.DropTable(
+                name: "channels");
+
+            migrationBuilder.DropTable(
+                name: "guilds");
+
+            migrationBuilder.DropTable(
+                name: "users");
+
+            migrationBuilder.DropTable(
+                name: "identity_instances");
+        }
+    }
+}

Foxchat.Chat/Migrations/ChatContextModelSnapshot.cs

@@ -0,0 +1,322 @@
+// <auto-generated />
+using System;
+using Foxchat.Chat.Database;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using NodaTime;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+
+#nullable disable
+
+namespace Foxchat.Chat.Migrations
+{
+    [DbContext(typeof(ChatContext))]
+    partial class ChatContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "8.0.5")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Channel", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<Guid>("GuildId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("guild_id");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("name");
+
+                    b.Property<string>("Topic")
+                        .HasColumnType("text")
+                        .HasColumnName("topic");
+
+                    b.HasKey("Id")
+                        .HasName("pk_channels");
+
+                    b.HasIndex("GuildId")
+                        .HasDatabaseName("ix_channels_guild_id");
+
+                    b.ToTable("channels", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Guild", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("name");
+
+                    b.Property<Guid>("OwnerId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("owner_id");
+
+                    b.HasKey("Id")
+                        .HasName("pk_guilds");
+
+                    b.HasIndex("OwnerId")
+                        .HasDatabaseName("ix_guilds_owner_id");
+
+                    b.ToTable("guilds", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.IdentityInstance", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<string>("BaseUrl")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("base_url");
+
+                    b.Property<string>("Domain")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("domain");
+
+                    b.Property<string>("PublicKey")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("public_key");
+
+                    b.Property<string>("Reason")
+                        .HasColumnType("text")
+                        .HasColumnName("reason");
+
+                    b.Property<int>("Status")
+                        .HasColumnType("integer")
+                        .HasColumnName("status");
+
+                    b.HasKey("Id")
+                        .HasName("pk_identity_instances");
+
+                    b.HasIndex("Domain")
+                        .IsUnique()
+                        .HasDatabaseName("ix_identity_instances_domain");
+
+                    b.ToTable("identity_instances", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Message", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<Guid>("AuthorId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("author_id");
+
+                    b.Property<Guid>("ChannelId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("channel_id");
+
+                    b.Property<string>("Content")
+                        .HasColumnType("text")
+                        .HasColumnName("content");
+
+                    b.Property<Instant?>("UpdatedAt")
+                        .HasColumnType("timestamp with time zone")
+                        .HasColumnName("updated_at");
+
+                    b.HasKey("Id")
+                        .HasName("pk_messages");
+
+                    b.HasIndex("AuthorId")
+                        .HasDatabaseName("ix_messages_author_id");
+
+                    b.HasIndex("ChannelId")
+                        .HasDatabaseName("ix_messages_channel_id");
+
+                    b.ToTable("messages", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.User", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .HasColumnType("uuid")
+                        .HasColumnName("id");
+
+                    b.Property<string>("Avatar")
+                        .HasColumnType("text")
+                        .HasColumnName("avatar");
+
+                    b.Property<Guid>("InstanceId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("instance_id");
+
+                    b.Property<string>("RemoteUserId")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("remote_user_id");
+
+                    b.Property<string>("Username")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("username");
+
+                    b.HasKey("Id")
+                        .HasName("pk_users");
+
+                    b.HasIndex("InstanceId")
+                        .HasDatabaseName("ix_users_instance_id");
+
+                    b.HasIndex("RemoteUserId", "InstanceId")
+                        .IsUnique()
+                        .HasDatabaseName("ix_users_remote_user_id_instance_id");
+
+                    b.HasIndex("Username", "InstanceId")
+                        .IsUnique()
+                        .HasDatabaseName("ix_users_username_instance_id");
+
+                    b.ToTable("users", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Core.Database.Instance", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("id");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("Id"));
+
+                    b.Property<string>("PrivateKey")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("private_key");
+
+                    b.Property<string>("PublicKey")
+                        .IsRequired()
+                        .HasColumnType("text")
+                        .HasColumnName("public_key");
+
+                    b.HasKey("Id")
+                        .HasName("pk_instance");
+
+                    b.ToTable("instance", (string)null);
+                });
+
+            modelBuilder.Entity("GuildUser", b =>
+                {
+                    b.Property<Guid>("GuildsId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("guilds_id");
+
+                    b.Property<Guid>("UsersId")
+                        .HasColumnType("uuid")
+                        .HasColumnName("users_id");
+
+                    b.HasKey("GuildsId", "UsersId")
+                        .HasName("pk_guild_user");
+
+                    b.HasIndex("UsersId")
+                        .HasDatabaseName("ix_guild_user_users_id");
+
+                    b.ToTable("guild_user", (string)null);
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Channel", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.Guild", "Guild")
+                        .WithMany("Channels")
+                        .HasForeignKey("GuildId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_channels_guilds_guild_id");
+
+                    b.Navigation("Guild");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Guild", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.User", "Owner")
+                        .WithMany("OwnedGuilds")
+                        .HasForeignKey("OwnerId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_guilds_users_owner_id");
+
+                    b.Navigation("Owner");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Message", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.User", "Author")
+                        .WithMany()
+                        .HasForeignKey("AuthorId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_messages_users_author_id");
+
+                    b.HasOne("Foxchat.Chat.Database.Models.Channel", "Channel")
+                        .WithMany()
+                        .HasForeignKey("ChannelId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_messages_channels_channel_id");
+
+                    b.Navigation("Author");
+
+                    b.Navigation("Channel");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.User", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.IdentityInstance", "Instance")
+                        .WithMany()
+                        .HasForeignKey("InstanceId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_users_identity_instances_instance_id");
+
+                    b.Navigation("Instance");
+                });
+
+            modelBuilder.Entity("GuildUser", b =>
+                {
+                    b.HasOne("Foxchat.Chat.Database.Models.Guild", null)
+                        .WithMany()
+                        .HasForeignKey("GuildsId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_guild_user_guilds_guilds_id");
+
+                    b.HasOne("Foxchat.Chat.Database.Models.User", null)
+                        .WithMany()
+                        .HasForeignKey("UsersId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("fk_guild_user_users_users_id");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.Guild", b =>
+                {
+                    b.Navigation("Channels");
+                });
+
+            modelBuilder.Entity("Foxchat.Chat.Database.Models.User", b =>
+                {
+                    b.Navigation("OwnedGuilds");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Foxchat.Chat/Program.cs

@@ -3,6 +3,7 @@ using Serilog;
 using Foxchat.Core;
 using Foxchat.Chat;
 using Foxchat.Chat.Database;
+using Newtonsoft.Json;
 
 var builder = WebApplication.CreateBuilder(args);
 
@@ -13,6 +14,15 @@ builder.AddSerilog(config.LogEventLevel);
 await BuildInfo.ReadBuildInfo();
 Log.Information("Starting Foxchat.Chat {Version} ({Hash})", BuildInfo.Version, BuildInfo.Hash);
 
+// Set the default converter to snake case as we use it in a couple places.
+JsonConvert.DefaultSettings = () => new JsonSerializerSettings
+{
+    ContractResolver = new DefaultContractResolver
+    {
+        NamingStrategy = new SnakeCaseNamingStrategy()
+    }
+};
+
 builder.Services
     .AddControllers()
     .AddNewtonsoftJson(options =>
@@ -38,7 +48,7 @@ app.UseAuthorization();
 app.MapControllers();
 
 using (var scope = app.Services.CreateScope())
-using (var context = scope.ServiceProvider.GetRequiredService<ChatContext>())
+await using (var context = scope.ServiceProvider.GetRequiredService<ChatContext>())
 {
     Log.Information("Initializing instance keypair...");
     if (await context.InitializeInstanceAsync())

Foxchat.Core/Federation/RequestSigningService.cs

@@ -31,23 +31,22 @@ public partial class RequestSigningService(ILogger logger, IClock clock, IDataba
     }
 
     public bool VerifySignature(
-        string publicKey, string encodedSignature, string dateHeader, string host, string requestPath, int? contentLength, string? userId)
+        string publicKey, string encodedSignature, SignatureData data)
     {
         var rsa = RSA.Create();
         rsa.ImportFromPem(publicKey);
 
         var now = _clock.GetCurrentInstant();
-        var time = ParseTime(dateHeader);
+        if ((now + Duration.FromMinutes(1)) < data.Time)
-        if ((now + Duration.FromMinutes(1)) < time)
         {
             throw new ApiError.IncomingFederationError("Request was made in the future");
         }
-        else if ((now - Duration.FromMinutes(1)) > time)
+        else if ((now - Duration.FromMinutes(1)) > data.Time)
         {
             throw new ApiError.IncomingFederationError("Request was made too long ago");
         }
 
-        var plaintext = GeneratePlaintext(new SignatureData(time, host, requestPath, contentLength, userId));
+        var plaintext = GeneratePlaintext(data);
         var plaintextBytes = Encoding.UTF8.GetBytes(plaintext);
         var hash = SHA256.HashData(plaintextBytes);
 
@@ -73,5 +72,5 @@ public partial class RequestSigningService(ILogger logger, IClock clock, IDataba
 
     private static readonly InstantPattern _pattern = InstantPattern.Create("ddd, dd MMM yyyy HH:mm:ss 'GMT'", CultureInfo.GetCultureInfo("en-US"));
     private static string FormatTime(Instant time) => _pattern.Format(time);
-    private static Instant ParseTime(string header) => _pattern.Parse(header).GetValueOrThrow();
+    public static Instant ParseTime(string header) => _pattern.Parse(header).GetValueOrThrow();
 }

Foxchat.Core/Federation/SignatureData.cs

@@ -8,4 +8,13 @@ public record SignatureData(
     string RequestPath,
     int? ContentLength,
     string? UserId
+)
+{
+    public static readonly SignatureData Empty = new(
+        Instant.MinValue,
+        string.Empty,
+        string.Empty,
+        null,
+        null
     );
+}

Foxchat.Identity/Database/IdentityContext.cs

@@ -11,9 +11,9 @@ public class IdentityContext : IDatabaseContext
 {
     private readonly NpgsqlDataSource _dataSource;
 
+    public override DbSet<Instance> Instance { get; set; }
     public DbSet<Account> Accounts { get; set; }
     public DbSet<ChatInstance> ChatInstances { get; set; }
-    public override DbSet<Instance> Instance { get; set; }
     public DbSet<Application> Applications { get; set; }
     public DbSet<Token> Tokens { get; set; }
     public DbSet<GuildAccount> GuildAccounts { get; set; }
@@ -55,6 +55,7 @@ public class IdentityContext : IDatabaseContext
     }
 }
 
+// ReSharper disable once UnusedType.Global
 public class DesignTimeIdentityContextFactory : IDesignTimeDbContextFactory<IdentityContext>
 {
     public IdentityContext CreateDbContext(string[] args)

Foxchat.Identity/Program.cs

@@ -51,7 +51,7 @@ app.UseCustomMiddleware();
 app.MapControllers();
 
 using (var scope = app.Services.CreateScope())
-using (var context = scope.ServiceProvider.GetRequiredService<IdentityContext>())
+await using (var context = scope.ServiceProvider.GetRequiredService<IdentityContext>())
 {
     Log.Information("Initializing instance keypair...");
     if (await context.InitializeInstanceAsync())