'Reverse engineering' networking.
Posted: 2017-01-24 08:39
If the moderators judge this topic as unacceptable, please delete it. By this topic I do not intend to do anything illegal. My aim is to understand what is going on under the hood when a network interface like wlan0 is set up by low level utilities like ifup and ifdown.
This is my analyses till now. If someone is able to give more details or to direct me to a good reading resource that will save me this investigation, it will be almost too good to be true. Networking is a vast subject as there are very diverse means of connecting computers.
On my machine with wlan0 up and active, this is what I found:
This is my analyses till now. If someone is able to give more details or to direct me to a good reading resource that will save me this investigation, it will be almost too good to be true. Networking is a vast subject as there are very diverse means of connecting computers.
On my machine with wlan0 up and active, this is what I found:
Code: Select all
/run/dhclient.wlan0.pid
Text Data: pid of running dhclient daemon
pgrep dhclient gives pid of running dhclient
How dhclient is run:
"dhclient -v -pf /run/dhclient.wlan0.pid -lf /var/lib/dhcp/dhclient.wlan0.leases wlan0"
wpa_supplicant.wlan0.pid
Text Data:pid of running wpa_supplicant
pgrep wpa_supplicant gives pid of running wpa_supplicant
How wpa_supplicant is run:
"/sbin/wpa_supplicant -s -B -P /run/wpa_supplicant.wlan0.pid -i wlan0 -D nl80211,wext -C /run/wpa_supplicant"