/// <summary>
/// This method will properly decrypt the connection request that is coming from Microsoft Graph.
/// </summary>
/// <param name="secretKeyBytes">The symmetric key established, and having the necessary storage done.</param>
/// <param name="request">The HTTP request that is coming in from Microsoft Graph.</param>
/// <returns>A unit of execution that contains a type of <see cref="ConnectRequest"/>.</returns>
public static async Task <ConnectRequest> DecryptConnectionRequest(
byte[] secretKeyBytes,
HttpRequest request)
{
if (request is null)
{
throw new ArgumentNullException(nameof(request));
}
string decryptedRequestBody = null;
// Step 1 - using a memory stream for the processing of the request.
using (MemoryStream ms = new MemoryStream())
{
await request.Body.CopyToAsync(ms).ConfigureAwait(false);
byte[] encryptedRequestBytes = ms.ToArray();
Aes256CbcHmacSha256Encryptor decryptor = new Aes256CbcHmacSha256Encryptor(secretKeyBytes);
byte[] decryptedRequestBodyBytes = decryptor.Decrypt(encryptedRequestBytes);
decryptedRequestBody = Encoding.UTF8.GetString(decryptedRequestBodyBytes);
}
// Step 2 - Parse the decrypted request into the correct model.
return(JsonConvert.DeserializeObject <ConnectRequest>(decryptedRequestBody));
}
/// <summary>
/// This method will properly decrypt the encrypted payload that is being received from Shifts.
/// </summary>
/// <param name="secretKeyBytes">The sharedSecret from Shifts casted into a byte array.</param>
/// <param name="request">The incoming request from Shifts UI that contains an encrypted payload.</param>
/// <returns>A unit of execution which contains the RequestModel.</returns>
private static async Task <RequestModel> DecryptEncryptedRequestFromShiftsAsync(byte[] secretKeyBytes, HttpRequest request)
{
string decryptedRequestBody = null;
// Step 1 - using a memory stream for the processing of the request.
using (MemoryStream ms = new MemoryStream())
{
await request.Body.CopyToAsync(ms).ConfigureAwait(false);
byte[] encryptedRequestBytes = ms.ToArray();
Aes256CbcHmacSha256Encryptor decryptor = new Aes256CbcHmacSha256Encryptor(secretKeyBytes);
byte[] decryptedRequestBodyBytes = decryptor.Decrypt(encryptedRequestBytes);
decryptedRequestBody = Encoding.UTF8.GetString(decryptedRequestBodyBytes);
}
// Step 2 - Parse the decrypted request into the correct model.
return(JsonConvert.DeserializeObject <RequestModel>(decryptedRequestBody));
}
public static async Task <T> ReadAsObjectAsync <T>(this HttpRequest request, string secret)
{
if (string.IsNullOrEmpty(secret))
{
return(JsonConvert.DeserializeObject <T>(await request.ReadAsStringAsync()));
}
var secretBytes = Encoding.UTF8.GetBytes(secret);
var decryptor = new Aes256CbcHmacSha256Encryptor(secretBytes);
using (var ms = new MemoryStream())
{
await request.Body.CopyToAsync(ms);
var decryptedPayload = decryptor.Decrypt(ms.ToArray());
return(JsonConvert.DeserializeObject <T>(Encoding.UTF8.GetString(decryptedPayload)));
}
}
