How to keep HTTP/2 connection alive till the request / response session is complete?

  • Thread starter Thread starter Bodapati
  • Start date Start date
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Bodapati

Guest
Hi,

I am currently using HttpDeclarePush to exploit the Server Push feature in HTTP/2.

I am able to successfully create all the parameters that this function accepts. But the issue is when HttpDeclarePush executes it returns a value of 1229 (ERROR_CONNECTION_INVALID)

On further investigation I found that the HttpHeaderConnection in _HTTP_HEADER_ID is actually passed in the function as 'close'. That implies that on every request response the server closes the connection and that is also happening in my case, I checked it in the log.

Here is the code.

class http2_native_module : public CHttpModule
{
public:
REQUEST_NOTIFICATION_STATUS OnBeginRequest(IN IHttpContext * p_http_context, IN IHttpEventProvider * p_provider)
{
HTTP_REQUEST_ID request_id;
const HTTPAPI_VERSION version = HTTPAPI_VERSION_2;

auto pHttpRequest = p_http_context->GetRequest();
auto phttpRequestRaw = pHttpRequest->GetRawHttpRequest();
HANDLE p_req_queue_handle = nullptr;
auto isHttp2 = phttpRequestRaw->Flags;

try {
const auto request_queue_handle = HttpCreateRequestQueue(version, nullptr, nullptr, NULL, &p_req_queue_handle);

const auto verb = phttpRequestRaw->Verb;
const auto http_path = L"/polyfills.0d74a55d0dbab6b8c32c.js"; //ITEM that I want to PUSH to client
const auto query = nullptr;


request_id = phttpRequestRaw->RequestId;
auto headers = phttpRequestRaw->Headers;

auto connId = phttpRequestRaw->ConnectionId;

WriteEventViewerLog(L"OnBeginRequest - Entering HTTPDECLAREPUSH");

headers.KnownHeaders[1].pRawValue = NULL;
headers.KnownHeaders[1].RawValueLength = 0;

const auto is_success = HttpDeclarePush(p_req_queue_handle, request_id, verb, http_path, query, &headers);

sprintf_s(szBuffer, "%lu", is_success);
Log("is_success value", szBuffer); //ERROR CODE 1229 here
HttpCloseRequestQueue(p_req_queue_handle);
}
catch (std::bad_alloc & e)
{
auto something = e;
}

return RQ_NOTIFICATION_CONTINUE;
}

I even tried to update the header connection value as below but it still gives me 1229.

headers.KnownHeaders[1].pRawValue = NULL;
headers.KnownHeaders[1].RawValueLength = 0;


I came to know that HTTP/2 actually ignores the content in HTTP HEADERs and uses some other mechanism as part of its FRAME.

This brings us to the next question on how we can keep the connection OPEN and is it something related to the FRAME (similar to HEADER) that HTTP/2 uses, if so, how C++ or rather Microsoft helps us to play and exploit with the FRAME in HTTP/2?

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