private async Task <bool> IsMd5Valid(HttpRequestMessage requestMessage)
{
var hashHeader = requestMessage.Content.Headers.ContentMD5;
//Console.WriteLine("Content-MD5:"+Convert.ToBase64String(hashHeader));
if (requestMessage.Content == null)
{
return(hashHeader == null || hashHeader.Length == 0);
}
var headerMd5Bytes = requestMessage.Content.Headers.ContentMD5;
var bytesContent = await requestMessage.Content.ReadAsByteArrayAsync();
var contentMd5Bytes = MD5Helper.ComputeHash(bytesContent);
if (!headerMd5Bytes.SequenceEqual(contentMd5Bytes))
{
//md5二次判断是为了兼容Java语言生成的MD5值，下面的代码用于比较java生成的Md5与C#进行比对。
//对于C# 直接比较MD5的md5 byte[]即可，无需比较C# md5的Bit形式
var headerMd5 = Convert.ToBase64String(headerMd5Bytes);//这个用于还原在java中放入Content-MD5中的String
var md5 = BitConverter.ToString(contentMd5Bytes).Replace("-", "");
// mLogger.Debug(string.Format("Md5 Compare(header and server calculate):\r\n{0}\r\n{1}",headerMd5,md5));
// Log.D(string.Format("Md5 Compare(header and server calculate):\r\n{0}\r\n{1}", headerMd5, md5));
return(string.Compare(md5, headerMd5, true) == 0);//不区分大小写进行比较
}
return(true);
//var hash = await MD5Helper.ComputeHash(requestMessage.Content);
//return hash.SequenceEqual(hashHeader);
}
public void MD5_Basic_uppercase()
{
string input = "MD5 test ABC _ 123 $%^";
string outputExpected = "13D3CD6193EDDBB721D0D19513BE210F";
string outputFunction = MD5Helper.ComputeHash(input, true);
Assert.AreEqual(outputExpected, outputFunction, "MD5 hash should be as expected.");
}
public void MD5_Basic_lowercase()
{
string input = "MD5 test ABC _ 123 $%^";
string outputExpected = "13d3cd6193eddbb721d0d19513be210f";
string outputFunction = MD5Helper.ComputeHash(input, false);
Assert.AreEqual(outputExpected, outputFunction, "MD5 hash should be as expected.");
}
private static byte[] ComputeHash(byte[] content, string algorithm)
{
switch (algorithm.ToUpper())
{
case "MD5":
return(MD5Helper.ComputeHash(content));
case "SHA256":
return(SHA256Helper.ComputeHash(content));
case "SHA384":
return(SHA384Helper.ComputeHash(content));
case "SHA512":
return(SHA512Helper.ComputeHash(content));
default:
return(SHA1Helper.ComputeHash(content));
}
}
/// <summary>
/// Validates the request message content header, <c>ContentMD5</c>, matches a newly calculated MD5 hash of the content.
/// </summary>
/// <param name="requestMessage">The request message to have its content validated.</param>
/// <returns><c>true</c> if the MD5 hash of the request content matches the <c>ContentMD5</c> content header; <c>false</c> otherwise.</returns>
private async Task <bool> IsMd5Valid(HttpRequestMessage requestMessage)
{
var content = requestMessage.Content;
var contentMD5Header = requestMessage.Content?.Headers?.ContentMD5;
// Validate that if there is no content then the there is also no ContentMD5 header (i.e. message body wasn't removed).
if (content == null || content.Headers.ContentLength == 0)
{
return((contentMD5Header == null) || (contentMD5Header.Length == 0));
}
// Validate that if there is content then there is also a ContentMD5 header (i.e. contentMD5 header wasn't removed or left out).
else if ((content.Headers.ContentLength > 0) && ((contentMD5Header == null) || (contentMD5Header.Length == 0)))
{
return(false);
}
// Validate the ContentMD5 header matches our calculated hash.
var hash = await MD5Helper.ComputeHash(content);
return(hash.SequenceEqual(contentMD5Header));
}
protected override async Task <HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
string reqSignature = "";
HttpResponseMessage response = null;
// Get digital signature if available.
if (request.Headers?.Authorization != null && request.Headers?.Authorization.Scheme == HmacApiAuthConfiguration.AuthenticationScheme)
{
reqSignature = request.Headers.Authorization.Parameter;
}
else
{
// We should just return here if there is no signature.
return(request.CreateErrorResponse(HttpStatusCode.Unauthorized, "Unauthorized request : Missing or invalid signature"));
}
// TODO : Check to see if signature is currently in cache. If so return now.
// TODO : Cache signature in memory for the validity period (5 mins) to ensure no request gets replayed.
try
{
// Call the base authentication handler.
response = await base.SendAsync(request, cancellationToken);
}
catch (Exception exception)
{
// Catch any authentication error messages and provide custom error message response.
response = request.CreateErrorResponse(HttpStatusCode.InternalServerError, "Error authenticating");
var respMsg = new StringBuilder();
respMsg.AppendLine("Error authenticating...");
respMsg.AppendLine("StatusCode : " + response.StatusCode);
respMsg.AppendLine("ReasonPhrase : " + response.ReasonPhrase);
respMsg.AppendLine("WwwAuthenticate : " + response.Headers.WwwAuthenticate.FirstOrDefault().ToString());
respMsg.AppendLine("RequestDate : " + request.Headers.Date.GetValueOrDefault().UtcDateTime.ToString(CultureInfo.InvariantCulture));
respMsg.AppendLine("ServerDate : " + (DateTimeOffset.Now));
respMsg.AppendLine();
respMsg.AppendLine("ExceptionMessage : " + exception.Message);
respMsg.AppendLine("ExceptionSource : " + exception.Source);
respMsg.AppendLine("ExceptionInnerMessage : " + exception.InnerException?.Message);
respMsg.AppendLine("ExceptionStackTrace : " + exception.StackTrace);
response.Content = new StringContent(respMsg.ToString());
}
// Catch any authentication failure message and provide custom error message response.
if (response != null && response.StatusCode == HttpStatusCode.Unauthorized)
{
var serverDate = DateTimeOffset.Now;
var respMsg = new StringBuilder();
respMsg.AppendLine("Authentication failed");
respMsg.AppendLine();
respMsg.AppendLine("Basic Details\n");
respMsg.AppendLine("URL : " + request.RequestUri.AbsoluteUri.ToLower());
respMsg.AppendLine("StatusCode : " + response.StatusCode);
respMsg.AppendLine("ReasonPhrase : " + response.ReasonPhrase);
//respMsg.AppendLine("WwwAuthenticate : " + response.Headers.WwwAuthenticate.FirstOrDefault().ToString());
respMsg.AppendLine("RequestDate : " + request.Headers.Date.GetValueOrDefault().ToString("r"));
respMsg.AppendLine("ServerDate : " + serverDate.ToString("r"));
respMsg.AppendLine("DateDifference : " + (serverDate - request.Headers.Date.GetValueOrDefault()));
respMsg.AppendLine();
string username = "";
if (request.Headers.Contains(HmacApiAuthConfiguration.UsernameHeader))
{
username = request.Headers.GetValues(HmacApiAuthConfiguration.UsernameHeader).First();
}
string signature = "";
if (request.Headers.Authorization != null && request.Headers.Authorization.Scheme == HmacApiAuthConfiguration.AuthenticationScheme)
{
signature = request.Headers.Authorization.Parameter;
}
string md5 = "";
string serverMd5 = "";
long? contentLength = 0;
if (request.Content != null)
{
contentLength = request.Content.Headers.ContentLength;
serverMd5 = Convert.ToBase64String(await MD5Helper.ComputeHash(request.Content)) == "1B2M2Y8AsgTpgAmY7PhCfg==" ? "" : Convert.ToBase64String(await MD5Helper.ComputeHash(request.Content));
if (request.Content.Headers.ContentMD5 != null && request.Content.Headers.ContentMD5.Length > 0)
{
md5 = Convert.ToBase64String(request.Content.Headers.ContentMD5);
}
}
bool validRequest = IsRequestValid(request);
string msgSigRep = _representBuilder.BuildRequestRepresentation(request);
string serverSignature = _sigCalc.Signature(_secretRepo.GetSecretForUser(username), msgSigRep);
respMsg.AppendLine("Auth Details\n");
respMsg.AppendLine("RequestValid : " + validRequest.ToString());
respMsg.AppendLine("Username : "******"ApiKey : " + _secretRepo.GetSecretForUser(username));
respMsg.AppendLine("Signature : " + signature);
respMsg.AppendLine("ServerSignature : " + serverSignature);
respMsg.AppendLine();
respMsg.AppendLine("Content Details\n");
respMsg.AppendLine("ContentMd5 : " + md5);
respMsg.AppendLine("ServerContentMd5 : " + serverMd5);
respMsg.AppendLine("CannonicalRep :\n" + msgSigRep);
respMsg.AppendLine("ContentLength : " + contentLength);
respMsg.AppendLine("ContentType : " + request.Content.Headers.ContentType);
respMsg.AppendLine("ContentMediaType : " + request.Content.Headers.ContentType.MediaType.ToLower());
respMsg.AppendLine("Content : \"" + await request.Content.ReadAsStringAsync() + "\"");
response.Content = new StringContent(respMsg.ToString());
}
return(response);
}
