Difference between revisions of "Wireshark"

From ArchWiki
Jump to: navigation, search
(Capturing as normal user: Extended section with notes on using sudo)
(wireshark-cli has the scripts)
(3 intermediate revisions by 2 users not shown)
Line 11: Line 11:
 
GTK frontend can be [[pacman|installed]] with the package {{Pkg|wireshark-gtk}}, available in the [[official repositories]].
 
GTK frontend can be [[pacman|installed]] with the package {{Pkg|wireshark-gtk}}, available in the [[official repositories]].
  
==Capturing as normal user==
+
== Capturing as normal user ==
  
 
Running Wireshark as root is insecure.
 
Running Wireshark as root is insecure.
Line 17: Line 17:
 
Arch Linux uses
 
Arch Linux uses
 
[http://wiki.wireshark.org/CaptureSetup/CapturePrivileges#Other_Linux_based_systems_or_other_installation_methods method from Wireshark wiki]
 
[http://wiki.wireshark.org/CaptureSetup/CapturePrivileges#Other_Linux_based_systems_or_other_installation_methods method from Wireshark wiki]
to separate privileges.  When {{Pkg|wireshark-gtk}} is installed, [[PKGBUILD#install|install script]] sets {{ic|/usr/bin/dumpcap}} capabilities.
+
to separate privileges.  When {{Pkg|wireshark-cli}} is installed, [[PKGBUILD#install|install script]] sets {{ic|/usr/bin/dumpcap}} capabilities.
  
{{bc|
+
{{hc|$ getcap /usr/bin/dumpcap|2=
$ getcap /usr/bin/dumpcap  
+
/usr/bin/dumpcap = cap_net_admin,cap_net_raw+eip
/usr/bin/dumpcap = cap_net_admin,cap_net_raw+eip}}
+
}}
  
 
{{ic|/usr/bin/dumpcap}} is the only process that has privileges to
 
{{ic|/usr/bin/dumpcap}} is the only process that has privileges to
Line 35: Line 35:
 
group to run programs with GID set to wireshark GID:
 
group to run programs with GID set to wireshark GID:
  
{{bc|1=%wheel ALL=(:wireshark) ALL}}
+
{{bc|1=%wheel ALL=(:wireshark) /usr/bin/wireshark, /usr/bin/tshark}}
  
 
Then run wireshark with
 
Then run wireshark with

Revision as of 21:45, 8 December 2013

Wireshark is a free and open-source packet analyzer. It is used for network troubleshooting, analysis, software and communications protocol development, and education. Originally named Ethereal, in May 2006 the project was renamed Wireshark due to trademark issues.

Installation

The wireshark package has been split into the CLI version and GTK frontend, which depends on the CLI.

CLI version can be installed with the package wireshark-cli, available in the official repositories.

GTK frontend can be installed with the package wireshark-gtk, available in the official repositories.

Capturing as normal user

Running Wireshark as root is insecure.

Arch Linux uses method from Wireshark wiki to separate privileges. When wireshark-cli is installed, install script sets /usr/bin/dumpcap capabilities.

$ getcap /usr/bin/dumpcap
/usr/bin/dumpcap = cap_net_admin,cap_net_raw+eip

/usr/bin/dumpcap is the only process that has privileges to capture packets. /usr/bin/dumpcap can only be run by root and members of the wireshark group.

To use wireshark as a normal user, add user to the wireshark group:

# gpasswd -a "username" wireshark

Another way is to use sudo to temporarily change group to wireshark. The following line allows all users in the wheel group to run programs with GID set to wireshark GID:

%wheel ALL=(:wireshark) /usr/bin/wireshark, /usr/bin/tshark

Then run wireshark with

$ sudo -g wireshark wireshark

A few capturing techniques

There are a number of different ways to capture exactly what you are looking for in Wireshark, by applying filters.

Note: To learn the filter syntax, see man pcap-filter(7).

Filtering TCP packets

If you want to see all the current TCP packets, type tcp into the "Filter" bar.

Filtering UDP packets

If you want to see all the current UDP packets, type udp into the "Filter" bar.

Filter packets to a specific IP Address

  • If you would like to see all the traffic going to a specific address, enter ip.dst == 1.2.3.4, replacing 1.2.3.4 with the IP address the outgoing traffic is being sent to.
  • If you would like to see all the incoming traffic for a specific address, enter ip.src == 1.2.3.4, replacing 1.2.3.4 with the IP address the incoming traffic is being sent to.