public void Load()
{
// look up the entry in the cache
var cache = Redis.Connection.GetDatabase();
try
{
var cachedItem = cache.StringGet(cacheId);
if (cachedItem.HasValue)
{
this.Cache = JsonConvert.DeserializeObject <UserTokenCacheItem>(cachedItem);
// ToDo: if the entry in Redis cache is older than 1 hour which is the default validity of AAD access token then kill it.
//var purpose = GetMachineKeyPurpose(Thread.CurrentPrincipal);
var purpose = GetMachineKeyPurpose();
//this.Deserialize((this.Cache == null) ? null : MachineKey.Unprotect(this.Cache.cacheBits, purpose));
//this.Deserialize((this.Cache == null) ? null : AesEncryptionHelper.Decrypt(this.Cache.cacheBits, purpose));
AesManagedCryptoLib _crypt = new AesManagedCryptoLib();
//this.Deserialize((this.Cache == null) ? null : _crypt.decrypt(this.Cache.CacheBits, purpose, localVector));
this.Deserialize((this.Cache == null) ? null : _crypt.decrypt(this.Cache.CacheBits, purpose, this.Cache.InitializationVector));
}
}
catch (Exception ex)
{
Trace.WriteLine("Exception in RedisTokenCache(id): " + ex.Message);
Cache = null;
}
}
// Notification raised before ADAL accesses the cache.
// This is your chance to update the in-memory copy from the cache, if the in-memory version is stale
void BeforeAccessNotification(TokenCacheNotificationArgs args)
{
try
{
var cache = Redis.Connection.GetDatabase();
var cachedItem = cache.StringGet(cacheId);
if (cachedItem.HasValue)
{
var status = JsonConvert.DeserializeObject <UserTokenCacheItem>(cachedItem);
if ((this.Cache != null) && (status.LastWrite > this.Cache.LastWrite))
{
this.Cache = status;
//var purpose = GetMachineKeyPurpose(Thread.CurrentPrincipal);
var purpose = GetMachineKeyPurpose();
//this.Deserialize((Cache == null) ? null : MachineKey.Unprotect(Cache.cacheBits, purpose));
//this.Deserialize((Cache == null) ? null : AesEncryptionHelper.Decrypt(Cache.cacheBits, purpose));
AesManagedCryptoLib _crypt = new AesManagedCryptoLib();
//this.Deserialize((this.Cache == null) ? null : _crypt.decrypt(this.Cache.CacheBits, purpose, localVector));
this.Deserialize((this.Cache == null) ? null : _crypt.decrypt(this.Cache.CacheBits, purpose, this.Cache.InitializationVector));
}
}
}
catch (Exception ex)
{
Trace.WriteLine("Exception in RedisTokenCache.BeforeAccessNotification: " + ex.Message);
}
}
// Notification raised after ADAL accessed the cache.
// If the HasStateChanged flag is set, ADAL changed the content of the cache
void AfterAccessNotification(TokenCacheNotificationArgs args)
{
// if state changed
if (this.HasStateChanged)
{
//var purpose = GetMachineKeyPurpose(Thread.CurrentPrincipal);
var purpose = GetMachineKeyPurpose();
AesManagedCryptoLib _crypt = new AesManagedCryptoLib();
string dynamicVector = AesManagedCryptoLib.GenerateRandomIV(16); //16 bytes = 128 bits
Cache = new UserTokenCacheItem
{
//cacheBits = MachineKey.Protect(this.Serialize(), purpose),
//cacheBits = AesEncryptionHelper.Encrypt(this.Serialize(), purpose),
//cacheBits = cryptoHelper.Encrypt(this.Serialize()),
//CacheBits = _crypt.encrypt(this.Serialize(), purpose, localVector),
CacheBits = _crypt.encrypt(this.Serialize(), purpose, dynamicVector),
InitializationVector = dynamicVector,
LastWrite = DateTime.Now.ToUniversalTime()
};
try
{
var cache = Redis.Connection.GetDatabase();
var cacheItemJson = JsonConvert.SerializeObject(Cache);
cache.StringSet(cacheId, cacheItemJson, TimeSpan.FromDays(1)); // could we use token expiry somehow?
}
catch (Exception ex)
{
Trace.WriteLine("Exception in RedisTokenCache.AfterAccessNotification: " + ex.Message);
}
this.HasStateChanged = false;
}
}
