Added E2EE stuff.

.gitignore

@@ -1,5 +1,6 @@
-bin/
-obj/
+/obj/
+/.idea/
+/bin/
 /packages/
 riderModule.iml
 /_ReSharper.Caches/

E2EeHelper.cs

@@ -0,0 +1,82 @@
+using System.Security.Cryptography;
+using System.Text;
+
+namespace RelayCore;
+
+public static class E2EeHelper
+{
+    public static (string publicKey, string privateKey) GenerateRsaKeyPair()
+    {
+        using var rsa = RSA.Create(2048);
+
+        var publicKey = Convert.ToBase64String(rsa.ExportSubjectPublicKeyInfo());
+        var privateKey = Convert.ToBase64String(rsa.ExportPkcs8PrivateKey());
+
+        return (publicKey, privateKey);
+    }
+
+    public static EncryptedMessagePayload EncryptForRecipient(string plainText, string recipientPublicKeyBase64)
+    {
+        var aesKey = RandomNumberGenerator.GetBytes(32);
+        var nonce = RandomNumberGenerator.GetBytes(12);
+        var plainBytes = Encoding.UTF8.GetBytes(plainText);
+        var cipherBytes = new byte[plainBytes.Length];
+        var tag = new byte[16];
+
+        using (var aes = new AesGcm(aesKey, 16))
+        {
+            aes.Encrypt(nonce, plainBytes, cipherBytes, tag);
+        }
+
+        var recipientPublicKey = Convert.FromBase64String(recipientPublicKeyBase64);
+        byte[] encryptedKey;
+
+        using (var rsa = RSA.Create())
+        {
+            rsa.ImportSubjectPublicKeyInfo(recipientPublicKey, out _);
+            encryptedKey = rsa.Encrypt(aesKey, RSAEncryptionPadding.OaepSHA256);
+        }
+
+        return new EncryptedMessagePayload
+        {
+            CipherText = Convert.ToBase64String(cipherBytes),
+            Nonce = Convert.ToBase64String(nonce),
+            Tag = Convert.ToBase64String(tag),
+            EncryptedKey = Convert.ToBase64String(encryptedKey)
+        };
+    }
+
+    public static string DecryptForRecipient(EncryptedMessagePayload payload, string recipientPrivateKeyBase64)
+    {
+        var encryptedKey = Convert.FromBase64String(payload.EncryptedKey);
+        var privateKey = Convert.FromBase64String(recipientPrivateKeyBase64);
+
+        byte[] aesKey;
+
+        using (var rsa = RSA.Create())
+        {
+            rsa.ImportPkcs8PrivateKey(privateKey, out _);
+            aesKey = rsa.Decrypt(encryptedKey, RSAEncryptionPadding.OaepSHA256);
+        }
+
+        var nonce = Convert.FromBase64String(payload.Nonce);
+        var tag = Convert.FromBase64String(payload.Tag);
+        var cipherBytes = Convert.FromBase64String(payload.CipherText);
+        var plainBytes = new byte[cipherBytes.Length];
+
+        using (var aes = new AesGcm(aesKey, 16))
+        {
+            aes.Decrypt(nonce, cipherBytes, tag, plainBytes);
+        }
+
+        return Encoding.UTF8.GetString(plainBytes);
+    }
+}
+
+public class EncryptedMessagePayload
+{
+    public required string CipherText { get; set; }
+    public required string Nonce { get; set; }
+    public required string Tag { get; set; }
+    public required string EncryptedKey { get; set; }
+}

Program.cs

@@ -1,58 +1,146 @@
-using System.ComponentModel.Design;
-using SurrealDb.Net;
+using SurrealDb.Net;
 using SurrealDb.Net.Models;
 using SurrealDb.Net.Models.Auth;
 using System.Text.Json;
 using PasswordHasher;
+using RelayCore;
 
 using var db = new SurrealDbClient("ws://127.0.0.1:8000/rpc");
 
 await db.SignIn(new RootAuth { Username = "root", Password = "secret" });
 await db.Use("test", "test");
 
-var user = new Users
+var keeper = await CreateUserAsync(db, "Keeper317", "Keeper317@gmail.com", "password");
+var kira = await CreateUserAsync(db, "Ru_Kira", "jduesling13@gmail.com", "password");
+
+Console.WriteLine($"Keeper created: {ToJsonString(keeper)}");
+Console.WriteLine($"Kira created: {ToJsonString(kira)}");
+
+var keeperKeys = E2EeHelper.GenerateRsaKeyPair();
+var kiraKeys = E2EeHelper.GenerateRsaKeyPair();
+
+KeyStorage.SavePrivateKey("Keeper317", keeperKeys.privateKey);
+KeyStorage.SavePrivateKey("Ru_Kira", kiraKeys.privateKey);
+
+await db.Create("user_keys", new UserKeys
 {
-    Username = "Keeper317",
-    Email = "Keeper317@gmail.com",
-    CreatedAt = DateTime.Now,
-    UpdatedAt = DateTime.Now,
-    LastLogin = DateTime.Now,
-    TwoFactorEnabled = false,
-    EmailVerified = false,
-    AccountStatus = (int) AccountStatuses.Active,
-    OnlineStatus = (int) OnlineStatuses.Online,
-};
-var created = await db.Create("users", user);
-Console.WriteLine($"Created Person: {ToJsonString(created)}");
-var hasher = new PasswordHasher.PasswordHasher();
-user.Password = hasher.HashPassword(created.Id + "password");
-user.UpdatedAt = DateTime.Now;
-user.LastLogin = DateTime.Now;
-user.Id = created.Id;
+    UserId = keeper.Id.ToString(),
+    PublicKey = keeperKeys.publicKey,
+    CreatedAt = DateTime.UtcNow,
+    UpdatedAt = DateTime.UtcNow
+});
 
-bool isValid = hasher.VerifyPassword(created.Id + "password", user.Password);
-Console.WriteLine($"Password match: {isValid}");
+await db.Create("user_keys", new UserKeys
+{
+    UserId = kira.Id.ToString(),
+    PublicKey = kiraKeys.publicKey,
+    CreatedAt = DateTime.UtcNow,
+    UpdatedAt = DateTime.UtcNow
+});
 
-var updated = await db.Merge<PasswordHash, Users>("users", new() { Id = created.Id,  Password = user.Password });
+Console.WriteLine("Public keys stored for both users.");
 
-// var updated = await db.Merge<ResponsibilityMerge, Person>(
-//     new() { Id = (TABLE, "8b4nwczy6x8f8zd5sslq"), Marketing = true }
-// );
-Console.WriteLine($"Updated Person: {ToJsonString(updated)}");
-//
-var people = await db.Select<Users>("users");
-Console.WriteLine($"Select Person: {ToJsonString(people)}");
-//
-// var queryResponse = await db.Query($"SELECT Marketing, count() AS Count FROM type::table({TABLE}) GROUP BY Marketing");
-// var groups = queryResponse.GetValue<List<Group>>(0);
-// Console.WriteLine($"Get Value as group: {ToJsonString(groups)}");
+var conversation = await db.Create("conversations", new Conversations
+{
+    CreatedByUserId = keeper.Id.ToString(),
+    CreatedAt = DateTime.UtcNow,
+    UpdatedAt = DateTime.UtcNow,
+    Title = "Keeper317 + Ru_Kira",
+    IsDirectMessage = true
+});
 
-await db.Delete("users");
+Console.WriteLine($"Conversation created: {ToJsonString(conversation)}");
 
+await db.Create("conversation_members", new ConversationMembers
+{
+    ConversationId = conversation.Id.ToString(),
+    UserId = keeper.Id.ToString(),
+    JoinedAt = DateTime.UtcNow
+});
+
+await db.Create("conversation_members", new ConversationMembers
+{
+    ConversationId = conversation.Id.ToString(),
+    UserId = kira.Id.ToString(),
+    JoinedAt = DateTime.UtcNow
+});
+
+Console.WriteLine("Conversation members added.");
+
+var encrypted = E2EeHelper.EncryptForRecipient("hello from Keeper317", kiraKeys.publicKey);
+
+var savedMessage = await db.Create("messages", new Messages
+{
+    ConversationId = conversation.Id.ToString(),
+    SenderUserId = keeper.Id.ToString(),
+    RecipientUserId = kira.Id.ToString(),
+    CipherText = encrypted.CipherText,
+    Nonce = encrypted.Nonce,
+    Tag = encrypted.Tag,
+    EncryptedKey = encrypted.EncryptedKey,
+    CreatedAt = DateTime.UtcNow
+});
+
+Console.WriteLine($"Encrypted message saved: {ToJsonString(savedMessage)}");
+
+var decrypted = E2EeHelper.DecryptForRecipient(encrypted, kiraKeys.privateKey);
+Console.WriteLine($"Decrypted for Ru_Kira: {decrypted}");
+
+return;
 
 static string ToJsonString(object? o)
 {
-    return JsonSerializer.Serialize(o, new JsonSerializerOptions { WriteIndented = true, });
+    return JsonSerializer.Serialize(o, new JsonSerializerOptions { WriteIndented = true });
+}
+
+static async Task<Users> CreateUserAsync(SurrealDbClient db, string username, string email, string rawPassword)
+{
+    var now = DateTime.UtcNow;
+
+    var user = new Users
+    {
+        Username = username,
+        Email = email,
+        CreatedAt = now,
+        UpdatedAt = now,
+        LastLogin = now,
+        TwoFactorEnabled = false,
+        EmailVerified = false,
+        AccountStatus = (int)AccountStatuses.Active,
+        OnlineStatus = (int)OnlineStatuses.Online,
+    };
+
+    var created = await db.Create("users", user);
+
+    var hasher = new PasswordHasher.PasswordHasher();
+    var passwordHash = hasher.HashPassword(created.Id.ToString() + rawPassword);
+
+    var updated = await db.Merge<PasswordHash, Users>(new PasswordHash
+    {
+        Id = created.Id,
+        Password = passwordHash
+    });
+
+    return updated;
+}
+
+public static class KeyStorage
+{
+    public static void SavePrivateKey(string username, string privateKey)
+    {
+        Directory.CreateDirectory("keys");
+        File.WriteAllText(Path.Combine("keys", $"{username}.private.key"), privateKey);
+    }
+
+    public static string LoadPrivateKey(string username)
+    {
+        return File.ReadAllText(Path.Combine("keys", $"{username}.private.key"));
+    }
+
+    public static bool PrivateKeyExists(string username)
+    {
+        return File.Exists(Path.Combine("keys", $"{username}.private.key"));
+    }
 }
 
 public class ResponsibilityMerge : Record
@@ -128,6 +216,43 @@ public class AuthAudits : Record
     public required string Details { get; set; }
     public required DateTime CreatedAt { get; set; }
 }
+
+public class UserKeys : Record
+{
+    public required string UserId { get; set; }
+    public required string PublicKey { get; set; }
+    public required DateTime CreatedAt { get; set; }
+    public required DateTime UpdatedAt { get; set; }
+}
+
+public class Conversations : Record
+{
+    public required string CreatedByUserId { get; set; }
+    public required DateTime CreatedAt { get; set; }
+    public required DateTime UpdatedAt { get; set; }
+    public string? Title { get; set; }
+    public bool IsDirectMessage { get; set; }
+}
+
+public class ConversationMembers : Record
+{
+    public required string ConversationId { get; set; }
+    public required string UserId { get; set; }
+    public required DateTime JoinedAt { get; set; }
+}
+
+public class Messages : Record
+{
+    public required string ConversationId { get; set; }
+    public required string SenderUserId { get; set; }
+    public required string RecipientUserId { get; set; }
+    public required string CipherText { get; set; }
+    public required string Nonce { get; set; }
+    public required string Tag { get; set; }
+    public required string EncryptedKey { get; set; }
+    public required DateTime CreatedAt { get; set; }
+}
+
 enum AccountStatuses
 {
     Active,