Stack Overflow
Stack Overflow

Questions tagged [netlink]

Netlink is a socket based inter process communication protocol for Linux systems. It is currently the preferred way, as of 2.6, of communicating with user space from the kernel.

337 questions
8
votes
1 answer

Netlink Sockets in C using the 3.X linux kernel

Hi, I've been working on trying to get Netlink sockets to work for the 3.2 linux kernel, but I cannot seem to figure out how to do it. I have looked around for examples of the basics of Netlink sockets, but it seems all of the examples I find are…
Zac Reynolds
  • 113
  • 2
  • 6
7
votes
2 answers

How to get notified about network interface changes with Netlist and RTMGRP_LINK signal?

I write a program which needs to get notified if the network interfaces have changed, in particular new one appeared or existed one gone. My research brought to the netlink and its RTMGRP_LINK signal. This manpage gives an example which is not clear…
Ruslan Gerasimov
  • 1,752
  • 1
  • 13
  • 20
7
votes
1 answer

How do Netlink and security interact with each other?

I understand that Netlink is the modern and correct way to communicate kernel and userspace in Linux. I have a kernel module that needs to be configurable, so I'm using Netlink to have it talk to a userspace application. Everything works wonders,…
Yd Ahhrk
  • 1,088
  • 12
  • 24
7
votes
2 answers

Live socket monitoring with netlink inet_diag

My goal is to monitor sockets and relate them to the applications that created them. I am aware of netstat, ss, lsof and so on and that they can list all sockets with their application. And I also know that I can parse /proc/net/tcp to get the…
BusDriverJoe
  • 123
  • 2
  • 4
7
votes
2 answers

Where m flag and o flag will be stored in Linux

I want to know the value of m flag and o flag of recently received Router Advertisement. From the kernel source code I came to know that m flag and o flag are stored. /* * Remember the managed/otherconf flags from most recently * received RA…
theB
  • 2,048
  • 2
  • 20
  • 29
7
votes
1 answer

How to query IPv6 NDP (neighbor discovery protocol) table for a specific neighbor

I am using Linux and trying to figure out how to query (via an API) the NDP table for a specific entry. The only example I have found so far (in the source for iproute2) uses Netlink and gets the entire table. Is there a way to query Netlink for a…
Tommy
  • 245
  • 4
  • 11
6
votes
1 answer

Sending a struct from kernel to userland via netlink

I'm trying to send a struct from a LKM to userland, based on this answer: Netlink Sockets in C using the 3.X linux kernel The code from the answer itself is perfectly compilable, but when I try to send a struct instead of a char *, I get segfaults…
alexandernst
  • 14,352
  • 22
  • 97
  • 197
6
votes
1 answer

AF_NETLINK (netlink) sockets using boost::asio

I'm writing multicast client/server application based on this and this; which work great. However, I would also need to do something when the number of active network interfaces in the computer changes, something like what the program in the example…
deinocheirus
  • 1,833
  • 5
  • 26
  • 44
6
votes
1 answer

Is it possible to communicate between two linux kernel module via netlink?

As all know, netlink it's user/kernel space communication mechanism. I want to communicate from my kernel module to an another. Another kernel module already has the netlink interface. Is it possible to make connection from kernel module to netlink,…
AlexeyPerevalov
  • 191
  • 3
  • 6
5
votes
1 answer

Linux - rtnetlink RTM_GETLINK - handle and understand answered data

I'am trying to understand how rtnetlink works, so I started playing with the idea to build a little library for my self to get into it. I've got to the point where sending/receiving netlink messages works fine. Right now I'am struggling on how to…
v01d
  • 73
  • 1
  • 6
5
votes
2 answers

How can I use a NETLINK socket to data from kernel space in PYTHON?

How can I use a NETLINK socket to data from kernel space in PYTHON?
1.618
  • 847
  • 2
  • 11
  • 19
5
votes
2 answers

How to receive Kernel uevents with Netlink socket?

I'm trying to receive uevent from the kernel via a netlink socket, when a USB device is (dis)connects. I have a python script that does the same job and it works, but I need the same functionality in C. So far I have this: #include…
Lasse Meyer
  • 1,429
  • 18
  • 38
5
votes
2 answers

Get CAN bitrate

I want to read the currently configured CAN bitrate of my socketcan socket in C++. I can see the bitrate with ip -det link show can0: 9: can0: mtu 16 qdisc pfifo_fast state UP mode DEFAULT group default qlen 10 link/can …
Laurenz
  • 1,810
  • 12
  • 25
5
votes
2 answers

Can I have more than 32 netlink sockets in kernelspace?

I have several kernel modules which need to interact with userspace. Hence, each module has a Netlink socket. My problem is that these sockets interfere with each other. This is because all of them register to the same Netlink address family…
Yd Ahhrk
  • 1,088
  • 12
  • 24
5
votes
1 answer

Linux Kernel Generic Netlink - Is it concurrent?

Say that i have registered a generic netlink interface using genl_register_family_with_ops with multiple callbacks. I don't see any warnings about it and I assume the callbacks are serially called but there is no information about how the callbacks…
Etherealone
  • 3,488
  • 2
  • 37
  • 56
1
2
3
…
22 23