Questions tagged [pcap]

The Packet Capture library provides a high level interface to packet capture systems.

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How to send pcap file to ethernet

I have a pcap file and need to send it to specific interface. How can I do it?
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extract application name from rawpacket

Sounds dumb, but can you extract application name from a packet/pcap. For eg: If a packet destination is to chrome process, can you extract that information from packet?
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TShark pcap filter command possibly simplified?

Object: to find the IP addresses of HTTP servers in a pcap file with a specific header string. Can or should the -l option to flush be used? One way: the following was done but am wondering if it can ...
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tc traffic shaping with HTB and CQB causes packet transmission gap inconsistencies

I am sorry if this is duplicate of https://serverfault.com/q/1076769/822163. I created that first and then realized the Linux and Unix stack exchange is the right place. Problem: When the tc HTB or ...
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Installing the latest version of libpcap & libpcap-dev

In my docker container I run the following command to install the pcap lib: apt-get install -y libpcap-dev When I run apt list --installed I see this weird output: libpcap-dev/oldstable,now 1.8.1-6 ...
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Turning ethernet on/off

I am porting a DOS application to linux and don't know a hell of a lot about linux. The application is a machine controller which uses ethernet as a high-speed serial port. Networking has nothing to ...
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pcap_inject payload misplaced

I have been using pcap_inject to send packets over wifi. The packets are sent but payload (data) is misplaced. For example, if I send "TEST", then in Wireshark data is shown as 1 byte and ...
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TCPDUMP Not capturing an smpp packet - but data visible in application log

I have tried using below tcpdump command to capture the traffic on one of our smpp ports: tcpdump -c500000 -w 2851.pcap -s 65535 -i any port 2851 -vv tcpdump -vvvvvvvvvvvvvvvvvvvvvvvvvv -w file.pcap ...
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Is tcpdump a client of rpcpad and implemented in pcap?

https://www.tcpdump.org/index.html#documentation has manpages for pcap, tcpdump, and rpcapd, but I don't find what relation is between the three. Is pcap a C library for implementing a client of ...
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How to extract domains related to "Client Hello" in a pcap file

I have a tcpdump (pcap) capture file and want to extract all domains. I do it with the following command: strings capture_file | grep -oiE '([a-zA-Z0-9][a-zA-Z0-9-]{1,61}\.){1,}(\.?[a-zA-Z]{2,}){1,}' |...
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Listen to a folder and modify incoming files on change

I want to convert pcap files to json files using shell script (and tshark). As soon as one or more new pcap files are copied into a folder, the command tshark should be executed and the resulting json ...
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#include pcap.h make fails for hcxtools

I'm running the latest version of Kali on a VirtualBox, and I cannot get hcxtools installed. More specifically, I can not figure out how to get the dependency pcap.h. Running make in /hcxtools ...
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Setting 'DF'-bit in IP-header inside pcap file

There is some .pcap-file with fragmented IP traffic. I replay this file with tcpreplay, but also I need to replay it with DF (don't fragment) bit set in some packets. I supposed that tcprewrite will ...
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Find username and password in pcap file

I am completing an assignment where I am given a pcap file to extract data from. The question is, Find username and password in pcap file. This is what I have so far. $ tshark -r assign1.pcap -R '...
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Increase send buffer/rate of packet injection on a wireless device?

I've written a custom wireless system/driver which works on top of a wifi card with packet injection and is in monitor mode. My program is based upon libpcap and uses pcap_inject to send packets over ...
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Reception of Frames with Destination MAC ALL ZERO

We are trying to implement GOOSE message (a multicast message, Generic Object Oriented Substation Event, part of IEC61850 protocol standard) subscription Module. In almost all cases, we are able to ...
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install failing for libpcap: recipe for target pcap-linux.o failed

Just finished installing ubuntu 16.04.1 desktop version. Now I am trying to install libpcap. So far performed the following steps: Downloaded libpcap-1.8.1.tar.gz tar -zxvf libpcap-1.8.1.tar.gz cd ...
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How to split a pcap file based on IP Address on RedHat

On my linux server I have a huge pcap trace file. I need to split this file based on some specific IP Address. How can I do that?
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"tail -f" using "tcpdump -r"

To display content of pcap file , we use : tcpdump -r /Path/to/syscontection.pcap; However, this command line does not follow the pcap file on realtime , like tail -f which follows a plain text . ...
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how to configure a linux machine to broadcast the incoming traffic

I want to configure a linux machine so that it can broadcast all the traffic received by it to other linux machine (in this case the connected nodes). Can someone help ?
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4 answers
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Why is tcpdump output file empty?

On my Red Hat Enterprise Linux Server release 6.5 when saving a tcpdump capture to a file with the -w option, the resulting file is empty: [root@plop ~]# tcpdump -n -w tcpdump.cap listening on eth0, ...
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How to passively capture from Unix domain sockets (AF_UNIX socket monitoring)?

TCP/IP and UDP captures can be made using tcpdump/dumpcap and produces a pcap/pcapng file which can be fed to Wireshark for further analysis. Does a similar tool exist for named Unix domain sockets? (...
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sum of all packets in pcap files

I'm trying to make a simple bash script to calculate packets captured in pcap files, I used tcpdump to get packets in each pcap file and add them using a bash script but it doesnt seem to work. #!/...
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Replay pcap on local machine only

RHEL 6.5. I have a capture of UDP packets, generated this way: tcpdump -nnXs 0 -i eth1 udp port 26477 and dst 233.86.230.111 -w ITCH.pcap I've moved this file over to a dev VM, and want to replay ...
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Snort PCAP file analysing doesn't write to alert file

I'm using snort in my ubuntu 14.04 virtual machine. This is how I installed snort. sudo apt-get update sudo apt-get install snort I haven't change /etc/snort/snort.conf or rules file. They remain as ...
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1 answer
2k views

How to use tshark or tcpdump to calculate bytes transmitted

I am using this command with tshark: tshark -r pcapfile "tcp and ip.src==192.168.1.1" -T text -V -x | grep 'Total Length' This essentially parses the pcap for only connections from the source ip and ...
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dsniff is unable to read wireshark pcap file

To try DSNIFF with -p (getting passwords with pcap) option First i've captured packets of my Open access point with airodump-ng and saved them to a pcap file and dsniff worked easily with no error ...
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TCPDump To Capture A Tracepath6 Datagram

I'm trying to use TCPDump to capture an IPv6 datagram using: tcpdump -c 1 -i eth1 -vvvs0 ip6 and dst host H2.net2 & tracepath6 H2.net2 I'm running this script on H1.net1; R12.net1 is the ...
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389 views

Break down a pcap file into individual flows and modify them

I have a pcap file and I want to: separate every flow separate responses and requests in each flow modify ip and port in some packets reply packets Is there any utility in linux that helps me for do ...
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How do I mcast multiple pcap files simultaneously with guaranteed ordering and controllable speed?

We capture many pcap files every day on many different multicast groups. For the purposes of testing & benchmarking, we wish to replay these files in an isolated environment and in a controlled ...
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