Set temporary touch sensitivity

Yubico.YubiKey/src/Yubico/YubiKey/FirmwareVersion.cs

@@ -38,6 +38,7 @@ public class FirmwareVersion : IComparable<FirmwareVersion>, IComparable, IEquat
         internal static readonly FirmwareVersion V4_4_0 = new FirmwareVersion(4, 4, 0);
         internal static readonly FirmwareVersion V4_5_0 = new FirmwareVersion(4, 5, 0);
         internal static readonly FirmwareVersion V5_3_0 = new FirmwareVersion(5, 3, 0);
+        internal static readonly FirmwareVersion V5_3_1 = new FirmwareVersion(5, 3, 1);
         internal static readonly FirmwareVersion V5_4_2 = new FirmwareVersion(5, 4, 2);
         internal static readonly FirmwareVersion V5_4_3 = new FirmwareVersion(5, 4, 3);
         internal static readonly FirmwareVersion V5_6_0 = new FirmwareVersion(5, 6, 0);

Yubico.YubiKey/src/Yubico/YubiKey/IYubiKeyDevice.cs

@@ -665,12 +665,33 @@ void SetLegacyDeviceConfiguration(
 
 
         /// <summary>
-        /// Sets the <see cref="IYubiKeyDeviceInfo.IsNfcRestricted"/> on the <see cref="YubiKeyDeviceInfo"/> 
+        /// Sets the <see cref="IYubiKeyDeviceInfo.IsNfcRestricted"/> on the <see cref="YubiKeyDeviceInfo"/>
         /// </summary>
         /// <param name="enabled">Set this value to true to enable, otherwise false</param>
         /// <exception cref="InvalidOperationException">
         /// The command failed to complete.
         /// </exception>
         void SetIsNfcRestricted(bool enabled);
+
+        /// <summary>
+        /// Temporarily set the threshold at which a capacitive touch should be considered active.
+        /// </summary>
+        /// <remarks>
+        /// <para>
+        /// The field is using arbitrary units and has a default value of `6`. A higher value increases the sensor
+        /// threshold which has the effect of decreasing the sensitivity of the sensor. Lower values increase the
+        /// sensitivity, but callers cannot reduce the threshold below the default value of `6` which is locked in at
+        /// manufacturing time. The value should not be any higher than `255`.
+        /// </para>
+        /// <para>
+        /// The value set here is only valid until the next time the YubiKey is power cycled. It does not persist.
+        /// </para>
+        /// <para>
+        /// You should typically not ever need to adjust this value. This is primarily used in the context of automatic
+        /// provisioning and testing where the YubiKey is being "touched" by electrically grounding the sensor.
+        /// </para>
+        /// </remarks>
+        /// <param name="value">The touch threshold to apply to the YubiKey. Must be a value greater than `6`.</param>
+        void SetTemporaryTouchThreshold(int value);
     }
 }

Yubico.YubiKey/src/Yubico/YubiKey/Management/Commands/SetDeviceInfoBaseCommand.cs

@@ -33,9 +33,11 @@ public class SetDeviceInfoBaseCommand
         private const byte ResetAfterConfigTag = 0x0c;
         private const byte NfcEnabledCapabilitiesTag = 0x0e;
         private const byte NfcRestrictedTag = 0x17;
+        private const byte TempTouchThresholdTag = 0x85;
 
         private byte[]? _lockCode;
         private byte[]? _unlockCode;
+        private ushort? _autoEjectTimeout;
 
         /// <summary>
         /// The length that a configuration lock code must be.
@@ -60,8 +62,6 @@ public class SetDeviceInfoBaseCommand
         /// </summary>
         public byte? ChallengeResponseTimeout { get; set; }
 
-        private ushort? _autoEjectTimeout;
-
         /// <summary>
         /// The CCID auto-eject timeout (in seconds). This field is only meaningful if the
         /// TouchEject flag in DeviceFlags is set. <see langword="null"/> to leave unchanged.
@@ -106,6 +106,26 @@ public int? AutoEjectTimeout
         /// </summary>
         public bool RestrictNfc { get; set; }
 
+        /// <summary>
+        /// Temporarily set the threshold at which a capacitive touch should be considered active.
+        /// </summary>
+        /// <remarks>
+        /// <para>
+        /// The field is using arbitrary units and has a default value of `6`. A higher value increases the sensor
+        /// threshold which has the effect of decreasing the sensitivity of the sensor. Lower values increase the
+        /// sensitivity, but callers cannot reduce the threshold below the default value of `6` which is locked in at
+        /// manufacturing time.
+        /// </para>
+        /// <para>
+        /// The value set here is only valid until the next time the YubiKey is power cycled. It does not persist.
+        /// </para>
+        /// <para>
+        /// You should typically not ever need to adjust this value. This is primarily used in the context of automatic
+        /// provisioning and testing where the YubiKey is being "touched" by electrically grounding the sensor.
+        /// </para>
+        /// </remarks>
+        public int? TemporaryTouchThreshold { get; set; }
+
         /// <summary>
         /// Initializes a new instance of the <see cref="SetDeviceInfoBaseCommand"/> class.
         /// </summary>
@@ -257,6 +277,11 @@ private byte[] GetTlvData()
                 buffer.WriteByte(NfcRestrictedTag, 1);
             }
 
+            if (TemporaryTouchThreshold.HasValue)
+            {
+                buffer.WriteByte(TempTouchThresholdTag, (byte)TemporaryTouchThreshold.Value);
+            }
+
             return buffer.Encode();
         }
     }

Yubico.YubiKey/src/Yubico/YubiKey/YubiKeyDevice.Instance.cs

@@ -695,6 +695,43 @@ public void SetLegacyDeviceConfiguration(
             }
         }
 
+        /// <inheritdoc />
+        /// <exception cref="NotSupportedException">
+        /// The YubiKey does not support this feature.
+        /// </exception>
+        /// <exception cref="ArgumentOutOfRangeException">
+        /// The value is less than `6` or greater than `255`.
+        /// </exception>
+        /// <exception cref="InvalidOperationException">
+        /// The YubiKey encountered an error and could not set the setting.
+        /// </exception>
+        public void SetTemporaryTouchThreshold(int value)
+        {
+            if (!this.HasFeature(YubiKeyFeature.TemporaryTouchThreshold))
+            {
+                throw new NotSupportedException(
+                    string.Format(
+                        CultureInfo.CurrentCulture,
+                        ExceptionMessages.NotSupportedByYubiKeyVersion));
+            }
+
+            if (value < 6 || value > 255)
+            {
+                throw new ArgumentOutOfRangeException(nameof(value));
+            }
+
+            var command = new MgmtCmd.SetDeviceInfoCommand
+            {
+                TemporaryTouchThreshold = value
+            };
+
+            IYubiKeyResponse response = SendConfiguration(command);
+            if (response.Status != ResponseStatus.Success)
+            {
+                throw new InvalidOperationException(response.StatusMessage);
+            }
+        }
+
         private IYubiKeyResponse SendConfiguration(MgmtCmd.SetDeviceInfoBaseCommand baseCommand)
         {
             IYubiKeyConnection? connection = null;

Yubico.YubiKey/src/Yubico/YubiKey/YubiKeyFeature.cs

@@ -69,6 +69,11 @@ public enum YubiKeyFeature
         /// </summary>
         FastUsbReclaim,
 
+        /// <summary>
+        /// The YubiKey allows temporarily adjusting the sensitivity of the capacitive touch sensor.
+        /// </summary>
+        TemporaryTouchThreshold,
+
         // OTP application features
 
         /// <summary>

Yubico.YubiKey/src/Yubico/YubiKey/YubiKeyFeatureExtensions.cs

@@ -97,6 +97,9 @@ public static bool HasFeature(this IYubiKeyDevice yubiKeyDevice, YubiKeyFeature
                 YubiKeyFeature.FastUsbReclaim =>
                     yubiKeyDevice.FirmwareVersion >= FirmwareVersion.V5_6_0,
 
+                YubiKeyFeature.TemporaryTouchThreshold =>
+                    yubiKeyDevice.FirmwareVersion >= FirmwareVersion.V5_3_1,
+
                 YubiKeyFeature.YubiHsmAuthApplication =>
                     yubiKeyDevice.FirmwareVersion >= FirmwareVersion.V5_4_3
                     && HasApplication(yubiKeyDevice, YubiKeyCapabilities.YubiHsmAuth),

Yubico.YubiKey/tests/utilities/Yubico/YubiKey/TestUtilities/HollowYubiKeyDevice.cs

@@ -244,5 +244,10 @@ public void SetIsNfcRestricted(bool enabled)
         {
             throw new NotImplementedException();
         }
+
+        public void SetTemporaryTouchThreshold(int value)
+        {
+            throw new NotImplementedException();
+        }
     }
 }