totp code generation on view login

src/App/Abstractions/Services/ITokenService.cs

@@ -18,5 +18,6 @@ namespace Bit.App.Abstractions
         string TokenUserId { get; }
         string TokenEmail { get; }
         string TokenName { get; }
+        bool TokenPremium { get; }
     }
 }

src/App/App.csproj

@@ -294,6 +294,7 @@
     <Compile Include="Pages\Vault\VaultEditLoginPage.cs" />
     <Compile Include="Pages\Vault\VaultListLoginsPage.cs" />
     <Compile Include="Services\PasswordGenerationService.cs" />
+    <Compile Include="Utilities\Base32.cs" />
     <Compile Include="Utilities\Crypto.cs" />
     <Compile Include="Utilities\Helpers.cs" />
     <Compile Include="Utilities\IdentityHttpClient.cs" />

src/App/Controls/LabeledValueCell.cs

@@ -8,7 +8,8 @@ namespace Bit.App.Controls
             string labelText = null,
             string valueText = null,
             string button1Text = null,
-            string button2Text = null)
+            string button2Text = null,
+            string subText = null)
         {
             var containerStackLayout = new StackLayout
             {
@@ -56,6 +57,18 @@ namespace Bit.App.Controls
                 VerticalOptions = LayoutOptions.CenterAndExpand
             };
 
+            if(subText != null)
+            {
+                Sub = new Label
+                {
+                    FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
+                    HorizontalOptions = LayoutOptions.End,
+                    VerticalOptions = LayoutOptions.Center
+                };
+
+                buttonStackLayout.Children.Add(Sub);
+            }
+
             if(button1Text != null)
             {
                 Button1 = new ExtendedButton
@@ -100,12 +113,18 @@ namespace Bit.App.Controls
                 containerStackLayout.AdjustPaddingForDevice();
             }
 
+            if(Sub != null && Button1 != null)
+            {
+                Sub.Margin = new Thickness(0, 0, 10, 0);
+            }
+
             containerStackLayout.Children.Add(buttonStackLayout);
             View = containerStackLayout;
         }
 
         public Label Label { get; private set; }
         public Label Value { get; private set; }
+        public Label Sub { get; private set; }
         public ExtendedButton Button1 { get; private set; }
         public ExtendedButton Button2 { get; private set; }
     }

src/App/Models/Page/VaultViewLoginPageModel.cs

@@ -13,6 +13,8 @@ namespace Bit.App.Models.Page
         private string _password;
         private string _uri;
         private string _notes;
+        private string _totpCode;
+        private int _totpSec = 30;
         private bool _revealPassword;
         private List<Attachment> _attachments;
 
@@ -194,6 +196,31 @@ namespace Bit.App.Models.Page
         public string ShowHideText => RevealPassword ? AppResources.Hide : AppResources.Show;
         public ImageSource ShowHideImage => RevealPassword ? ImageSource.FromFile("eye_slash") : ImageSource.FromFile("eye");
 
+        public string TotpCode
+        {
+            get { return _totpCode; }
+            set
+            {
+                _totpCode = value;
+                PropertyChanged(this, new PropertyChangedEventArgs(nameof(TotpCode)));
+                PropertyChanged(this, new PropertyChangedEventArgs(nameof(TotpCodeFormatted)));
+            }
+        }
+        public int TotpSecond
+        {
+            get { return _totpSec; }
+            set
+            {
+                _totpSec = value;
+                PropertyChanged(this, new PropertyChangedEventArgs(nameof(TotpSecond)));
+                PropertyChanged(this, new PropertyChangedEventArgs(nameof(TotpColor)));
+            }
+        }
+        public bool TotpLow => TotpSecond <= 7;
+        public Color TotpColor => !string.IsNullOrWhiteSpace(TotpCode) && TotpLow ? Color.Red : Color.Black;
+        public string TotpCodeFormatted => !string.IsNullOrWhiteSpace(TotpCode) ?
+            string.Format("{0} {1}", TotpCode.Substring(0, 3), TotpCode.Substring(3)) : null;
+
         public List<Attachment> Attachments
         {
             get { return _attachments; }

src/App/Pages/Vault/VaultAddLoginPage.cs

@@ -168,12 +168,12 @@ namespace Bit.App.Pages
 
                 var login = new Login
                 {
-                    Uri = UriCell.Entry.Text?.Encrypt(),
-                    Name = NameCell.Entry.Text?.Encrypt(),
-                    Username = UsernameCell.Entry.Text?.Encrypt(),
-                    Password = PasswordCell.Entry.Text?.Encrypt(),
-                    Notes = NotesCell.Editor.Text?.Encrypt(),
-                    Totp = TotpCell.Entry.Text?.Encrypt(),
+                    Name = NameCell.Entry.Text.Encrypt(),
+                    Uri = string.IsNullOrWhiteSpace(UriCell.Entry.Text) ? null : UriCell.Entry.Text.Encrypt(),
+                    Username = string.IsNullOrWhiteSpace(UsernameCell.Entry.Text) ? null : UsernameCell.Entry.Text.Encrypt(),
+                    Password = string.IsNullOrWhiteSpace(PasswordCell.Entry.Text) ? null : PasswordCell.Entry.Text.Encrypt(),
+                    Notes = string.IsNullOrWhiteSpace(NotesCell.Editor.Text) ? null : NotesCell.Editor.Text.Encrypt(),
+                    Totp = string.IsNullOrWhiteSpace(TotpCell.Entry.Text) ? null : TotpCell.Entry.Text.Encrypt(),
                     Favorite = favoriteCell.On
                 };
 

src/App/Pages/Vault/VaultEditLoginPage.cs

@@ -177,12 +177,17 @@ namespace Bit.App.Pages
                     return;
                 }
 
-                login.Uri = UriCell.Entry.Text?.Encrypt(login.OrganizationId);
-                login.Name = NameCell.Entry.Text?.Encrypt(login.OrganizationId);
-                login.Username = UsernameCell.Entry.Text?.Encrypt(login.OrganizationId);
-                login.Password = PasswordCell.Entry.Text?.Encrypt(login.OrganizationId);
-                login.Notes = NotesCell.Editor.Text?.Encrypt(login.OrganizationId);
-                login.Totp = TotpCell.Entry.Text?.Encrypt(login.OrganizationId);
+                login.Name = NameCell.Entry.Text.Encrypt(login.OrganizationId);
+                login.Uri = string.IsNullOrWhiteSpace(UriCell.Entry.Text) ? null :
+                    UriCell.Entry.Text.Encrypt(login.OrganizationId);
+                login.Username = string.IsNullOrWhiteSpace(UsernameCell.Entry.Text) ? null :
+                    UsernameCell.Entry.Text.Encrypt(login.OrganizationId);
+                login.Password = string.IsNullOrWhiteSpace(PasswordCell.Entry.Text) ? null :
+                    PasswordCell.Entry.Text.Encrypt(login.OrganizationId);
+                login.Notes = string.IsNullOrWhiteSpace(NotesCell.Editor.Text) ? null :
+                    NotesCell.Editor.Text.Encrypt(login.OrganizationId);
+                login.Totp = string.IsNullOrWhiteSpace(TotpCell.Entry.Text) ? null :
+                    TotpCell.Entry.Text.Encrypt(login.OrganizationId);
                 login.Favorite = favoriteCell.On;
 
                 if(FolderCell.Picker.SelectedIndex > 0)

src/App/Pages/Vault/VaultViewLoginPage.cs

@@ -19,6 +19,7 @@ namespace Bit.App.Pages
         private readonly ILoginService _loginService;
         private readonly IUserDialogs _userDialogs;
         private readonly IDeviceActionService _deviceActionService;
+        private readonly ITokenService _tokenService;
 
         public VaultViewLoginPage(string loginId)
         {
@@ -26,6 +27,7 @@ namespace Bit.App.Pages
             _loginService = Resolver.Resolve<ILoginService>();
             _userDialogs = Resolver.Resolve<IUserDialogs>();
             _deviceActionService = Resolver.Resolve<IDeviceActionService>();
+            _tokenService = Resolver.Resolve<ITokenService>();
 
             Init();
         }
@@ -39,6 +41,7 @@ namespace Bit.App.Pages
         public LabeledValueCell PasswordCell { get; set; }
         public LabeledValueCell UriCell { get; set; }
         public LabeledValueCell NotesCell { get; set; }
+        public LabeledValueCell TotpCodeCell { get; set; }
         private EditLoginToolBarItem EditItem { get; set; }
         public List<AttachmentViewCell> AttachmentCells { get; set; }
 
@@ -91,6 +94,15 @@ namespace Bit.App.Pages
                 }
             });
 
+            // Totp
+            TotpCodeCell = new LabeledValueCell(AppResources.VerificationCodeTotp, button1Text: AppResources.Copy, subText: "--");
+            TotpCodeCell.Value.SetBinding(Label.TextProperty, nameof(VaultViewLoginPageModel.TotpCodeFormatted));
+            TotpCodeCell.Value.SetBinding(Label.TextColorProperty, nameof(VaultViewLoginPageModel.TotpColor));
+            TotpCodeCell.Button1.Command = new Command(() => Copy(Model.TotpCode, AppResources.VerificationCodeTotp));
+            TotpCodeCell.Sub.SetBinding(Label.TextProperty, nameof(VaultViewLoginPageModel.TotpSecond));
+            TotpCodeCell.Sub.SetBinding(Label.TextColorProperty, nameof(VaultViewLoginPageModel.TotpColor));
+            TotpCodeCell.Value.FontFamily = Helpers.OnPlatform(iOS: "Courier", Android: "monospace", WinPhone: "Courier");
+
             // Notes
             NotesCell = new LabeledValueCell();
             NotesCell.Value.SetBinding(Label.TextProperty, nameof(VaultViewLoginPageModel.Notes));
@@ -129,6 +141,7 @@ namespace Bit.App.Pages
                 PasswordCell.Button1.WidthRequest = 40;
                 PasswordCell.Button2.WidthRequest = 59;
                 UsernameCell.Button1.WidthRequest = 59;
+                TotpCodeCell.Button1.WidthRequest = 59;
                 UriCell.Button1.WidthRequest = 75;
             }
 
@@ -209,6 +222,38 @@ namespace Bit.App.Pages
                 Table.Root.Add(AttachmentsSection);
             }
 
+            // Totp
+            var removeTotp = login.Totp == null || (!_tokenService.TokenPremium && !login.OrganizationUseTotp);
+            if(!removeTotp)
+            {
+                var totpKey = login.Totp.Decrypt(login.OrganizationId);
+                removeTotp = string.IsNullOrWhiteSpace(totpKey);
+                if(!removeTotp)
+                {
+                    Model.TotpCode = Crypto.Totp(totpKey);
+                    removeTotp = string.IsNullOrWhiteSpace(Model.TotpCode);
+                    if(!removeTotp)
+                    {
+                        TotpTick(totpKey);
+                        Device.StartTimer(new TimeSpan(0, 0, 1), () =>
+                        {
+                            TotpTick(totpKey);
+                            return true;
+                        });
+
+                        if(!LoginInformationSection.Contains(TotpCodeCell))
+                        {
+                            LoginInformationSection.Add(TotpCodeCell);
+                        }
+                    }
+                }
+            }
+
+            if(removeTotp && LoginInformationSection.Contains(TotpCodeCell))
+            {
+                LoginInformationSection.Remove(TotpCodeCell);
+            }
+
             base.OnAppearing();
         }
 
@@ -273,6 +318,18 @@ namespace Bit.App.Pages
             _userDialogs.Toast(string.Format(AppResources.ValueHasBeenCopied, alertLabel));
         }
 
+        private void TotpTick(string totpKey)
+        {
+            var now = Helpers.EpocUtcNow() / 1000;
+            var mod = now % 30;
+            Model.TotpSecond = (int)(30 - mod);
+
+            if(mod == 0)
+            {
+                Model.TotpCode = Crypto.Totp(totpKey);
+            }
+        }
+
         private class EditLoginToolBarItem : ExtendedToolbarItem
         {
             private readonly VaultViewLoginPage _page;

src/App/Repositories/AccountsApiRepository.cs

@@ -5,13 +5,12 @@ using Bit.App.Abstractions;
 using Bit.App.Models.Api;
 using Plugin.Connectivity.Abstractions;
 using Newtonsoft.Json;
+using Bit.App.Utilities;
 
 namespace Bit.App.Repositories
 {
     public class AccountsApiRepository : BaseApiRepository, IAccountsApiRepository
     {
-        private static readonly DateTime _epoc = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
-
         public AccountsApiRepository(
             IConnectivity connectivity,
             IHttpService httpService,
@@ -125,7 +124,7 @@ namespace Bit.App.Repositories
                     {
                         return await HandleErrorAsync<DateTime?>(response).ConfigureAwait(false);
                     }
-                    return ApiResult<DateTime?>.Success(_epoc.AddMilliseconds(ms), response.StatusCode);
+                    return ApiResult<DateTime?>.Success(Helpers.Epoc.AddMilliseconds(ms), response.StatusCode);
                 }
                 catch
                 {

src/App/Resources/AppResources.Designer.cs

@@ -2122,6 +2122,15 @@ namespace Bit.App.Resources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Verification Code (TOTP).
+        /// </summary>
+        public static string VerificationCodeTotp {
+            get {
+                return ResourceManager.GetString("VerificationCodeTotp", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Could not send verification email. Try again..
         /// </summary>

src/App/Resources/AppResources.resx

@@ -925,4 +925,8 @@
   <data name="AuthenticatorKey" xml:space="preserve">
     <value>Authenticator Key (TOTP)</value>
   </data>
+  <data name="VerificationCodeTotp" xml:space="preserve">
+    <value>Verification Code (TOTP)</value>
+    <comment>Totp code label</comment>
+  </data>
 </root>

src/App/Services/TokenService.cs

@@ -2,6 +2,7 @@
 using Bit.App.Abstractions;
 using System.Text;
 using Newtonsoft.Json.Linq;
+using Bit.App.Utilities;
 
 namespace Bit.App.Services
 {
@@ -19,8 +20,6 @@ namespace Bit.App.Services
         private string _refreshToken;
         private string _authBearer;
 
-        private static readonly DateTime _epoc = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
-
         public TokenService(ISecureStorageService secureStorage)
         {
             _secureStorage = secureStorage;
@@ -73,7 +72,7 @@ namespace Bit.App.Services
                     throw new InvalidOperationException("No exp in token.");
                 }
 
-                return _epoc.AddSeconds(Convert.ToDouble(decoded["exp"].Value<long>()));
+                return Helpers.Epoc.AddSeconds(Convert.ToDouble(decoded["exp"].Value<long>()));
             }
         }
 
@@ -97,6 +96,7 @@ namespace Bit.App.Services
         public string TokenUserId => DecodeToken()?["sub"].Value<string>();
         public string TokenEmail => DecodeToken()?["email"].Value<string>();
         public string TokenName => DecodeToken()?["name"].Value<string>();
+        public bool TokenPremium => (DecodeToken()?["premium"].Value<bool?>()).GetValueOrDefault(false);
 
         public string RefreshToken
         {

src/App/Utilities/Base32.cs

@@ -0,0 +1,72 @@
+using System;
+
+namespace Bit.App.Utilities
+{
+    // ref: https://github.com/aspnet/Identity/blob/dev/src/Microsoft.Extensions.Identity.Core/Base32.cs
+    // with some modifications for cleaning input
+    public static class Base32
+    {
+        private static readonly string _base32Chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567";
+
+        public static byte[] FromBase32(string input)
+        {
+            if(input == null)
+            {
+                throw new ArgumentNullException(nameof(input));
+            }
+
+            input = input.ToUpperInvariant();
+            var cleanedInput = string.Empty;
+            foreach(var c in input)
+            {
+                if(_base32Chars.IndexOf(c) < 0)
+                {
+                    continue;
+                }
+
+                cleanedInput += c;
+            }
+
+            input = cleanedInput;
+            if(input.Length == 0)
+            {
+                return new byte[0];
+            }
+
+            var output = new byte[input.Length * 5 / 8];
+            var bitIndex = 0;
+            var inputIndex = 0;
+            var outputBits = 0;
+            var outputIndex = 0;
+
+            while(outputIndex < output.Length)
+            {
+                var byteIndex = _base32Chars.IndexOf(input[inputIndex]);
+                if(byteIndex < 0)
+                {
+                    throw new FormatException();
+                }
+
+                var bits = Math.Min(5 - bitIndex, 8 - outputBits);
+                output[outputIndex] <<= bits;
+                output[outputIndex] |= (byte)(byteIndex >> (5 - (bitIndex + bits)));
+
+                bitIndex += bits;
+                if(bitIndex >= 5)
+                {
+                    inputIndex++;
+                    bitIndex = 0;
+                }
+
+                outputBits += bits;
+                if(outputBits >= 8)
+                {
+                    outputIndex++;
+                    outputBits = 0;
+                }
+            }
+
+            return output;
+        }
+    }
+}

src/App/Utilities/Crypto.cs

@@ -152,5 +152,36 @@ namespace Bit.App.Utilities
 
             return true;
         }
+
+        // ref: https://github.com/mirthas/totp-net/blob/master/TOTP/Totp.cs
+        public static string Totp(string b32Key)
+        {
+            var key = Base32.FromBase32(b32Key);
+            if(key == null || key.Length == 0)
+            {
+                return null;
+            }
+
+            var now = Helpers.EpocUtcNow() / 1000;
+            var sec = now / 30;
+
+            var secBytes = BitConverter.GetBytes(sec);
+            if(BitConverter.IsLittleEndian)
+            {
+                Array.Reverse(secBytes, 0, secBytes.Length);
+            }
+
+            var algorithm = WinRTCrypto.MacAlgorithmProvider.OpenAlgorithm(MacAlgorithm.HmacSha1);
+            var hasher = algorithm.CreateHash(key);
+            hasher.Append(secBytes);
+            var hash = hasher.GetValueAndReset();
+
+            var offset = (hash[hash.Length - 1] & 0xf);
+            var i = ((hash[offset] & 0x7f) << 24) | ((hash[offset + 1] & 0xff) << 16) |
+                ((hash[offset + 2] & 0xff) << 8) | (hash[offset + 3] & 0xff);
+            var code = i % (int)Math.Pow(10, 6);
+
+            return code.ToString().PadLeft(6, '0');
+        }
     }
 }

src/App/Utilities/Helpers.cs

@@ -5,6 +5,13 @@ namespace Bit.App.Utilities
 {
     public static class Helpers
     {
+        public static readonly DateTime Epoc = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
+
+        public static long EpocUtcNow()
+        {
+            return (long)(DateTime.UtcNow - Epoc).TotalMilliseconds;
+        }
+
         public static T OnPlatform<T>(T iOS = default(T), T Android = default(T),
             T WinPhone = default(T), T Windows = default(T))
         {