I have the following topology:
I'm trying to perform an iperf from server2 to server4 and a problem arise: it seems (by analyzing the traffic using wireshark) it doesn't install any rules on the destination's switch. If I try an iperf between two servers of the same switch everything works fine. I don't understand why this problem arise. Can anyone help me? Any suggestion may be usefull.
The code which installs the flows on the switches is the following:
//source Switch != destination Switch
IOFSwitch srcSwitch = sw;
IOFSwitch dstSwitch = this.floodlightProvider.getSwitch(destSwitchID);
/* Create match:
* source Mac: always host mac
* dest Mac: always dest host mac
* source Ip: vIP or external
* dest Ip: rIP or vIP */
int srcIp = IPv4.toIPv4Address(toVirtualIp(sourceIp));
//get inPort of dest Switch on the inter-switch link
short inPort = topology.getInterSwitchPort(destSwitchID);
OFMatch matchDst = createMatch(srcHostMac, destHostMac, srcIp, destIp, inPort);
short[] actionsLengthDst = {0};
int dstIp = IPv4.toIPv4Address(toRealIp(destIp));
// Initialize list of actions
//realSrcToVirtualSrc = false because sourceIp has not to be translated to realIp in the dest switch
ArrayList<OFAction> actionsDst = createActions(false, 0, //vIP
virtualDestToRealDest, dstIp, //rIP
destHostMac, destSwitchID, actionsLengthDst,
false);
OFFlowMod ruleDst = createRule(matchDst, actionsDst, actionsLengthDst[0]);
System.out.println("Installing flows to dest OF switch ID " + dstSwitch.getId());
try {
dstSwitch.write(ruleDst, cntx);
} catch (Exception e) {
e.printStackTrace();
return false;
}
/* Create match:
* source Mac: always host mac
* dest Mac: gateway MAC or host MAC
* source Ip: rIP
* dest Ip: rIP or vIP */
OFMatch matchSrc = createMatch(srcHostMac, destMac, sourceIp, destIp, pi.getInPort());
short[] actionsLengthSrc = {0};
// Initialize list of actions
//virtualDestToRealDest = false because destIp has not to be translated to realIp int the source switch
ArrayList<OFAction> actionsSrc = createActions(realSrcToVirtualSrc, sourceIp, //not translated (always)
false, 0, //not translated (rIP or vIP)
destHostMac, sw.getId(), actionsLengthSrc,
false);
OFFlowMod ruleSrc = createRule(matchSrc, actionsSrc, actionsLengthSrc[0]);
System.out.println("Installing flows to source OF switch ID " + srcSwitch.getId());
try {
srcSwitch.write(ruleSrc, cntx);
} catch (Exception e) {
e.printStackTrace();
return false;
}
Thanks in advance.
Related
I am discovering the Plc4x java implementation which seems to be of great interest in our field. But the youth of the project and the documentation makes us hesitate. I have been able to implement the basic hello world for reading out of our PLCs, but I was unable to write. I could not find how the addresses are handled and what the maskwrite, andMask and orMask fields mean.
Please can somebody explain to me the following example and detail how the addresses should be used?
#Test
void testWriteToPlc() {
// Establish a connection to the plc using the url provided as first argument
try( PlcConnection plcConnection = new PlcDriverManager().getConnection( "modbus:tcp://1.1.2.1" ) ){
// Create a new read request:
// - Give the single item requested the alias name "value"
var builder = plcConnection.writeRequestBuilder();
builder.addItem( "value-" + 1, "maskwrite:1[1]/2/3", 2 );
var writeRequest = builder.build();
LOGGER.info( "Synchronous request ..." );
var syncResponse = writeRequest.execute().get();
}catch(Exception e){
e.printStackTrace();
}
}
I have used PLC4x for writing using the modbus driver with success. Here is some sample code I am using:
public static void writePlc4x(ProtocolConnection connection, String registerName, byte[] writeRegister, int offset)
throws InterruptedException {
// modbus write works ok writing one record per request/item
int size = 1;
PlcWriteRequest.Builder writeBuilder = connection.writeRequestBuilder();
if (writeRegister.length == 2) {
writeBuilder.addItem(registerName, "register:" + offset + "[" + size + "]", writeRegister);
}
...
PlcWriteRequest request = writeBuilder.build();
request.execute().whenComplete((writeResponse, error) -> {
assertNotNull(writeResponse);
});
Thread.sleep((long) (sleepWait4Write * writeRegister.length * 1000));
}
In the case of modbus writing there is an issue regarding the return of the writer Future, but the write is done. In the modbus use case I don't need any mask stuff.
I am currently using HttpDeclarePushto 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 HttpDeclarePushexecutes it returns a value of 1229 (ERROR_CONNECTION_INVALID) - https://learn.microsoft.com/en-us/windows/desktop/debug/system-error-codes--1000-1299-.
On further investigation I found that the HttpHeaderConnection in _HTTP_HEADER_ID (https://learn.microsoft.com/en-us/windows/desktop/api/http/ne-http-_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 understand from https://http2.github.io/http2-spec/ 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 HTTP2 uses, if so, how C++ or rather Microsoft helps us to play and exploit with the FRAME in HTTP2?
I would like to set a breakpoint in an application before it starts to run, so that I can make sure the application does not pass the breakpoint on startup.
In order to set a breakpoint you need to do something like:
EventRequestManager reqMan = vm.eventRequestManager();
BreakpointRequest bpReq = reqMan.createBreakpointRequest(locationForBreakpoint);
bpReq.enable();
In order to get the Location for the breakpoint, you can do something like:
Method method = location.method();
List<Location> locations = method.locationsOfLine(55);
Location locationForBreakpoint = locations.get(0);
In order to get a Method you can do something like:
classType.concreteMethodByName(methodNname, String signature)
However in order to get that classType you seem to require an ObjectReference which seems to require a running JVM.
Is there any way to set the breakpoint before the application JVM runs, to be sure the breakpoint is not passed during application startup?
First of all start you target program using a LaunchingConnector to get back the target virtual machine.
VirtualMachineManager vmm = Bootstrap.virtualMachineManager();
LaunchingConnector lc = vmm.launchingConnectors().get(0);
// Equivalently, can call:
// LaunchingConnector lc = vmm.defaultConnector();
Map<String, Connector.Argument> env = lc.defaultArguments();
env.get("main").setValue("p.DebugDummy");
env.get("suspend").setValue("true");
env.get("home").setValue("C:/Program Files/Java/jdk1.7.0_51");
VirtualMachine vm = lc.launch(env);
(change environment values according to your needs,but remember to start target VM with suspended=true).
With this VM in you hand intercept a ClassPrepareEvent using a ClassPrepareRequest.
ClassPrepareRequest r = reqMan.createClassPrepareRequest();
r.addClassFilter("myclasses.SampleClass");
r.enable();
Create a ClassPrepareEvent handler
executor.execute(()-> {
try {
while(true)
{
EventQueue eventQueue = vm.eventQueue();
EventSet eventSet = eventQueue.remove();
EventIterator eventIterator = eventSet.eventIterator();
if (eventIterator.hasNext()) {
Event event = eventIterator.next();
if(event instanceof ClassPrepareEvent) {
ClassPrepareEvent evt = (ClassPrepareEvent) event;
ClassType classType = (ClassType) evt.referenceType();
List<Location> locations = referenceType.locationsOfLine(55);
Location locationForBreakpoint = locations.get(0);
vm.resume();
}
}
}
} catch (InterruptedException | AbsentInformationException | IncompatibleThreadStateException e) {
e.printStackTrace();
}
}
then resume target VM with a call to vm.resume() to run program.
I hope this solve your problem.
We have tried the approach suggested at:
https://msdn.microsoft.com/en-us/library/windows/hardware/dn312121(v=vs.85).aspx
https://msdn.microsoft.com/en-us/library/windows/hardware/dn303343(v=vs.85).aspx
We are able to find out list of all the magneticDevices using below code snippet
var magneticDevices = await DeviceInformation.FindAllAsync(aqsFilter);
but we are not able to get HidDevice object from the below code. It is giving null.
HidDevice device = await HidDevice.FromIdAsync(magneticDevices[0].Id
We have also set device capabilities in the app manifest file like below.
<DeviceCapability Name="humaninterfacedevice">
<Device Id="vidpid:0ACD 0520">
<Function Type="usage:0001 0006"/>
</Device>
</DeviceCapability>
<DeviceCapability Name="usb">
<Device Id="vidpid:0ACD 0520">
<Function Type="winUsbId:4d1e55b2-f16f-11cf-88cb-001111000030"/>
</Device>
</DeviceCapability>
Code for the complete Function
private async Task<bool> HasCardReader()
{
bool hasCardReader = false;
ushort usagePage = 0x0001;
ushort usageId = 0x0006;
ushort vendorId = 0x0ACD;
ushort productId = 0x0520;
var aqsFilter = HidDevice.GetDeviceSelector(usagePage, usageId, vendorId, productId);
var magneticDevices = await DeviceInformation.FindAllAsync(aqsFilter);
try
{
if (magneticDevices != null && magneticDevices.Count > 0)
{
HidDevice device = await HidDevice.FromIdAsync(magneticDevices[0].Id, Windows.Storage.FileAccessMode.Read);
inputReportEventHandler = new TypedEventHandler<HidDevice, HidInputReportReceivedEventArgs>(this.OnInputReportEvent);
device.InputReportReceived += inputReportEventHandler;
var watcher = DeviceInformation.CreateWatcher(aqsFilter);
watcher.Added += WatcherAdded;
watcher.Removed += WatcherRemoved;
watcher.Start();
hasCardReader = true;
}
else
{
}
}
catch (Exception ex)
{
Logging.LoggingSessionScenario.LogMessageAsync(ex.Message, LoggingLevel.Error);
}
return hasCardReader;
}
There are several reasons for the null return value, but I don't think there is something wrong with your code, since you can find the device by calling FindAllAsync. I will suggest you to troubleshoot this issue using this official HIDDevice sample on GitHub.
I successfully connected to my external hid device with that sample by changing the vid & pid & usagepage & usageid to my device.
In EventHandlerForDevice.cs, find the function OpenDeviceAsync, and you will notice the following possible reasons when null is returned by FromIdAsync.
else
{
successfullyOpenedDevice = false;
notificationStatus = NotifyType.ErrorMessage;
var deviceAccessStatus = DeviceAccessInformation.CreateFromId(deviceInfo.Id).CurrentStatus;
if (deviceAccessStatus == DeviceAccessStatus.DeniedByUser)
{
notificationMessage = "Access to the device was blocked by the user : " + deviceInfo.Id;
}
else if (deviceAccessStatus == DeviceAccessStatus.DeniedBySystem)
{
// This status is most likely caused by app permissions (did not declare the device in the app's package.appxmanifest)
// This status does not cover the case where the device is already opened by another app.
notificationMessage = "Access to the device was blocked by the system : " + deviceInfo.Id;
}
else
{
// Most likely the device is opened by another app, but cannot be sure
notificationMessage = "Unknown error, possibly opened by another app : " + deviceInfo.Id;
}
}
Have a try with that sample(Scenario1) and change the ids in both appxmanifest and SampleConfiguration.cs(class Device). If you cannot see your device in the device list, that means the configuration is incorrect for your device.
I have created a processing-java sketch. This sketch is the server. All I want this program to do is that the client and server can connect and write messages(sentences) between each other. Case 1 was successful, but case 2 was not. I have explained the process for each case and what went wrong/successful.
Case 1) On the same computer(Mac), I started the server program and on Terminal("Command Prompt" on Mac), I typed telnet local host 5204 and the client(Mac) connected with the server(Mac). I was able to type sentences (or Strings) between the server and client and it was successful. So whatever sentence I type in the server, it was visible to the client and vice versa. Note: The server and client were both in the same computer.
Case 2) On the Mac, I started the server program. On another computer(Windows 7)
I connected to the server via Command Prompt. The connection was successful. In this case, the Strings could be sent from the server to the client and the Strings were visible to the client. But when I tried to send Strings to the server from the client, the server could only receive the information character by character, not as an entire sentence/String. I tried changing the port number, the client device, the frameRate, but I still had no success.
This is my problem. Please comment if my question could be clearer or if I need to give more details. Thank you for answering.
Below is my Server code:
import processing.net.*;
Server myServer;
//Strings from server and client
String typing = "";
String c = "";
void setup() {
size(400, 400);
//creating server on port 5204
myServer = new Server(this, 5204);
}
void draw() {
background(255);
//displaying server's text and client's text
fill(0);
text(typing, 100, 100);
text("Client: " + c, 100, 150);
Client client = myServer.available();
if(client != null) {
//reading input from client
c = client.readString();
c.trim();
}
}
void keyPressed() {
//Server can type sentences to client
if(key == '\n') {
myServer.write(typing + '\n');
typing = "";
}else{
typing = typing + key;
}
}
Did you try ncat for Windows?
With it you can try: echo Text to send & echo. | ncat localhost 5204
Source