I'm reading packets with wireshark and most of these packets are repeating multiple times per second (identical). I don't want to see those. They're too many to manually filter (thousands).
So what I'd like is some filter like:
This packet was already captured/displayed, I won't display it again.
Is this possible using wireshark or is any other software (linux) available for this? I definitely need this feature in live capture so doing some magic with a dump file is not an option.
Related
I do have two computers which are used to control an industrial plant. One of them controls the plant, the other is used as a failsafe. They are directly connected over ethernet, and the inactive" one just mirrors the display of the main controller.
I did capture the network traffic between the two and when i open it up in wireshark i see its all X11 traffic. It does include the initial connection request and also includes all the "draw calls" in plain text.
I now want to "replay" this captured stream and recreate the screen content from it. Is there any program available which can do so? Ideally directly from the wireshark capture file
My thoughts so far:
I can easily replay the network data itself and send it to some socket, but the communication is specific to the session, e.g. some commands refer to specific handle values set up earlier. Its unlikely a new session would work with the same values so i cant just pipe it into some program
What you see from your connection is only your connection requests + events relevant to the windows created by you ( or other's client windows where your connection sets an event mask ), and because of that quite a lot is lost. I'm not aware of the programs that can reconstruct best possible version of the screen from one client traffic but it's certainly not possible to have 100% accurate copy of the screen and best possible model will be far away from real screen (unless your connection periodically polls for backing store content of each mapped window).
I captured some packets from server(like: ip.addr == 111.11.11.111 && data), and want to send them again. How to do it? Googling didn't yield any easy way not involving some complex stuff resulting in a script being able to send only this specific request, without any flexibility.
I'am using only Windows 10
A very simple program that can do this is PlayCap from Signal 11 Software, but there are several others too. You might want to have a look at the various Traffic Generators listed on the Wireshark Tools wiki page for other potential solutions.
I have a problem where I need to check the TCP packets on a machine.
We use a closed source VOIP system here and I want to open a program when an incoming calls happens.
The VOIP system's software shows the call, however has no functionality to call external software.
I used Wireshark to capture my PCs packets and I'm able to filter the packets easily by
ip.src==AAA.BBB.CCC.DDD && giop.request_op == "pushEvents" && giop.len > 300 && tcp contains "CallInfo"
Now I can work with this package if my custom software could read the package from pipe
Is there a library for purebasic that can do this capturing and filtering??
Alternatively Is there a way to trigger wireshark (console start) so it outputs the filtered data to pipe? (I noticed tshark could do this but does not support this display filter)
Thanks for any constructive answer not hitting me for rtfm ;-)
tshark is just a terminal/console interface to the same engine as GUI Wireshark. It should support all the same protocol dissectors and display filters as GUI app.
I'm pretty sure you're doing something wrong while launching it. Please provide more info why you didn't manage to get tshark working.
To solve your problem: I would launch a tshark with the filter you've come up with so only those packets are displayed on the output. Then I would pipe the output to the simple python/bash/whatever script that launches the app you want on every line of input.
You will also need to take care of specific situations like:
ensure the input line is what it was supposed to be (you can get error lines etc from tshark)
perhaps avoid launching the app if it's already running
I need to dump some incoming packets and then prevent them from going up the stack, so that applications won't process them.
Now, tcpdump works at layer 2, right? So ideally I should find some tool that I'd use right after tcpdump that drops selected packets. The filter I apply in tcpdump and when I drop packets is going to be the same.
Anything that already does this?
Now, tcpdump works at layer 2, right? So ideally I should find some tool that I'd use right after tcpdump that drops selected packets.
Tcpdump captures from a network at the link layer, yes. However, "captures", in this case, means "passively taps into the network, getting copies of all packets received and sent". It does not tap into the network in a fashion that allows it to prevent those packets from being processed by the network stack. Think of it as being similar to tapping a phone line - whoever's tapping the line can listen to the conversation, but they can't prevent somebody on one side of the conversation from hearing what the person on the other side says.
Anything that already does this?
There might be, but the mechanism that it would use to do so is probably going to be very dependent on the operating system it's running on. What operating system is the machine on which you need to trap the packets running.
I am trying to find a solution to monitor the traffic (in and out) through a specific port. It is not required to capture the packets, or do anyting else. What it does is to be a traffic listener to make sure there are messages sent to or received from this port every 10 minutes. It has to be running at the background all the time (like a daemon), and without significant performance impact. Based on my research, one choice is to use an existing tool to do that. There are a bunch of tools out there to monitor or sniff the traffic, such as wireshark. Well, seems most of them monitor the traffic passing through a interface, instead of a port, or they can't run as a daemon. Another choice to write a program to do this. SharpPcap seems to be a good choice, but I still need to capture and analyze the packets to know whether such traffic exist. Could somebody suggest what I should do?
SharpPcap handles packet capturing in the same manner as Wireshark, so you can set filters to limit the packet being captured to a specific port the same way in SharpPcap as you can in wireshark. Except, SharpPcap will be a much lighter weight option vs wireshark.
Download the SharpPcap source tree and look at the Example05.SetFilter.
To narrow down the results so you capture only the packets you want to see you'll need to employ a few filters.
Pcap uses a common language across all applications that use it do specify the filters to set. Capture programs that use winpcap (windows) or libpcap (*nix) include, sharppcap, wireshark, pcap.net, winpcap, libpcap, tcpdump, etc... For a great resource on how to use pcap filters see this link.
Here are the filters you need:
ether host ehost
port port
Where the ehost is the MAC address of the computer sending/receiving the packets and the port is the port you want to monitor. So the full filter string would be.
SetFilter("ether host ff:ff:ff:ff:ff:ff and port 60");
The MAC and port here are for illustration purposes only, you'd obviously change them with the values that pertain to your specific setup.
This, used in the SetFilter example will simply print out a line of info with the time of when the packet was captured to the command line every time a packet is captured and meets the criteria if your filter.
If you want more detailed info about the packet, such as info from the headers or the packet's payload, you'll need to parse the incoming raw packet. Be sure to ask for help on the sourceforge project's forum if you need some tips on how to do this. The project developers are very active and always willing to help.
The best way that will limit the impact your tool will have on performance is via an ETW (Event Tracing for Windows) Real-time Consumer (i.e. a tool that activates an ETW trace and reads it immediately instead of saving it to a file). This MSDN sample is a great way to see how to do this via C# and it gives you some code to get started.