public async Task <string> TryAlternativeLogin()
{
try
{
PasswordInfoModel model = await GetPasswordInfoModelAsync();
if (model != null)
{
var key = await GetSignedKeyAsync(model.KeyPhrase);
if (key != null)
{
if (model.EncryptedPassword != null)
{
var myPassword = _encryptionService.DecryptRaw(model.EncryptedPassword, key);
return(myPassword);
}
}
}
}
catch (Exception e)
{
LogHelper.Instance.LogException(e);
}
return(null);
}
public async void InvalidateAlternativeLogin()
{
PasswordInfoModel model = await GetPasswordInfoModelAsync();
if (model != null)
{
model.EncryptedPassword = null;
await _storageService.SetCachedTextFileAsync(FileName, JsonConvert.SerializeObject(model));
}
}
public async void RegisterValidPassword(string hashedPassword)
{
PasswordInfoModel model = await GetPasswordInfoModelAsync();
if (model != null)
{
if (model.EncryptedPassword == null)
{
var key = await GetSignedKeyAsync(model.KeyPhrase);
if (key != null)
{
model.EncryptedPassword = _encryptionService.EncryptRaw(hashedPassword, key);
await _storageService.SetCachedTextFileAsync(FileName, JsonConvert.SerializeObject(model));
}
}
}
}
private async Task <PasswordInfoModel> GetPasswordInfoModelAsync()
{
PasswordInfoModel model = null;
var pwInfoFile = await _storageService.GetCachedTextFileAsync(FileName);
if (pwInfoFile != null)
{
model = JsonConvert.DeserializeObject <PasswordInfoModel>(pwInfoFile);
}
if (model == null)
{
if (!await KeyCredentialManager.IsSupportedAsync())
{
return(null);
}
model = new PasswordInfoModel
{
KeyPhrase = "sign this keyphrase of this bookmarked application to get a secure string"
};
var keyCreationResult =
await KeyCredentialManager.RequestCreateAsync(AccountId, KeyCredentialCreationOption.ReplaceExisting);
if (keyCreationResult.Status == KeyCredentialStatus.Success)
{
model.PreferPassword = false;
}
else if (keyCreationResult.Status == KeyCredentialStatus.UserPrefersPassword)
{
model.PreferPassword = true;
}
await _storageService.SetCachedTextFileAsync(FileName, JsonConvert.SerializeObject(model));
}
return(model);
}
