Secure Storage for Xamarin.iOS

SecureStorage.cs

using System;
using System.Threading.Tasks;
using Security;
using Foundation;
using System.Collections.Generic;

namespace SecureStorageTest
{
	public class SecureStorage
	{
		private string serviceName = "secureSTorageTest";

		public Task StoreValueAsync(string key, string value)
		{
			var queryRecord = new SecRecord (SecKind.GenericPassword)
			{
				Service = this.serviceName,
				Label = key,
				Account = key
			};


			SecStatusCode resultCode;
			var data = SecKeyChain.QueryAsRecord (queryRecord, out resultCode);


			if (resultCode == SecStatusCode.Success) {
				var deleteResultCode = SecKeyChain.Remove (queryRecord);
				if (deleteResultCode != SecStatusCode.Success) {
					throw new Exception ("The key already exists in the secure storage and is not possible update it");
				}
			}

			SecKeyChain.Add (new SecRecord(SecKind.GenericPassword)
				{
					Service = this.serviceName,
					Account = key,
					Label = key,
					ValueData = NSData.FromString(value, NSStringEncoding.UTF8)
				});

			return Task.FromResult (0);
		}


		public Task<string> GetValueAsync(string key)
		{
			var queryRecord = new SecRecord (SecKind.GenericPassword) {
				Account = key,
				Label = key,
				Service = this.serviceName
			};

			SecStatusCode resultCode;
			var existingRecord = SecKeyChain.QueryAsRecord (queryRecord, out resultCode);

			if (resultCode != SecStatusCode.Success) {
				throw new KeyNotFoundException (string.Format("The Secure storage does not contain the key '{0}'", key));
			}

			string result = NSString.FromData (existingRecord.ValueData, NSStringEncoding.UTF8);
			return Task.FromResult (result);
		}
	}
}