public async Task <string> CryptAsync(string userId, string data)
{
var cypher = await strongKeyProvider.GetStrongKeyAsync(userId);
var result = aes.Crypt(cypher.Secret.ToUrlSafeBase64(), data);
return(result);
}
public async Task <string> GetOrSetAesKeyAsync(string userId)
{
logger.LogInformation($"try to get {userId} cacheKey");
string cacheKey = CacheKeyFactories.GenerateAesKeyCache(userId);
var result = await CacheGetString(cacheKey);
if (result != null)
{
return(result.Aes);
}
var strongKey = await strongKeyProvider.GetStrongKeyAsync(userId);
if (strongKey == null)
{
logger.LogInformation($"Key was not exist. User id: {userId}");
throw new ApiError(new ServerException("Internal server error"));
}
var cacheModel = new CryptCacheModel()
{
Aes = strongKey.Secret.ToUrlSafeBase64()
};
await CacheSetString(cacheKey, cacheModel, TimeSpan.FromMinutes(5));
return(cacheModel.Aes);
}
public async Task <IDictionary <string, string> > CryptMessageAsync(MessageBuildDto message) // крипт сообщений. используется для отправки сообщения от сервера
{
var strongKey = await strongKeyProvider.GetStrongKeyAsync(message.ReceiverId);
string cryptedAesKey = aes.Crypt(strongKey.Secret.ToUrlSafeBase64(), message.Aes);
var result = new ConcurrentDictionary <string, string>();
var tasks = new List <Task>();
var sessions = await sessionProvider.GetModelsBySearchPredicate(x => x.UserId == message.ReceiverId);
foreach (var session in sessions)
{
tasks.Add(Task.Run(() =>
{
var signMessage = new SignMessageDto()
{
MessageId = message.MessageId,
CryptedText = message.Text,
CryptedAes = cryptedAesKey,
ReceiverId = message.ReceiverId,
SenderId = message.SenderId,
SessionId = message.SessionId,
Created = DateTime.Now
};
string sign = rsa.SignData(session.ServerPrivateKey, signMessage.ObjectToBytes());
var item = new MessageDto()
{
Message = signMessage,
Sign = sign
};
result.TryAdd(session.SessionId, JsonConvert.SerializeObject(item));
}));
}
await Task.WhenAll(tasks);
return(result);
}