2
votes
0answers
24 views

Last data traffic time for a TCP socket

Is it possible, to find out when was the last time there was any traffic on an opened TCP socket? Keepalive and timeout timers are based on this statistic, so I guess it has to be stored somewhere. ...
0
votes
0answers
12 views

Manipulating skb_header_pointer using sockets [migrated]

I'm trying to create a test to show that the patch for CVE-2014-2523 has been correctly applied to our system. The issue is that a netfilter module has a few faulty calls made to skb_header_pointer. ...
1
vote
1answer
88 views

How can I allow applications to bind to any address in a subnet assigned to an interface?

I recently got a static IPv6 /56 prefix of my own from Freenet6, and am trying to allow applications to bind arbitrary addresses in the prefix. I modified the tunnel creation script that gogoc uses in ...
2
votes
2answers
76 views

Detect open sockets manually (not using nc or similar)?

I'm trying to debug a network problem on a embedded system which has a very limited set of userspace applications. Meaning I can't use any of the following sudo lsof -i sudo netstat -lptu sudo ...
4
votes
1answer
100 views

Does traffic addressed to one of a Linux system's own interfaces ever leave the system?

I have two separate servers running on the same port on a Linux system, one binded to the loopback interface, and the other to the public Ethernet interface. If I connect a client on that system to ...
1
vote
1answer
129 views

Communication to device is lost when network starts on boot up?

I have an application that opens a socket on port 4444 to a device (/dev/linkToDevice). The "linkToDevice" is a link to ttyUSB0. The application is a c++ program of which is now a daemon and runs at ...
2
votes
1answer
73 views

Custom application running on embedded device - do I need to register my listening port in /etc/services?

I have written an application that will run on an embedded device. The installation is very minimal and uses busybox and not many other things. Part of the software includes a listener thread that ...
5
votes
1answer
269 views

In bash, can I asynchronously open sockets and use them later?

I had no idea that Bash supported so many advanced features! I started working on a simple network program to try and use some of these things I found. My particular program is a basic redis client ...
1
vote
1answer
665 views

Default value for SO_RCVTIMEO option on Solaris

Is there any way to find out what is the default value set for option SO_RCVTIMEO on Solaris 10? If there is a way to find out how would one go about changing it? P.S. I am aware of ability of ...
0
votes
1answer
566 views

pcap and raw socket [closed]

I want to develop an application (module or user-level if possible) to create a raw socket in RHEL stealing all level-2 packets directly from kernel (without being routed or handled by other open ...
3
votes
1answer
378 views

User associated with a socket

I use ss -p to see TCP sockets information. But process info are not printed for some sockets. Below: $ ss -p4 State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB 0 0 ...
1
vote
1answer
368 views

How to limit all tcp traffic to the network interface the session was initiated on?

I have an embedded linux system with two network interfaces (lan0, wlan0) that are configured to the same subnet. A server on this system accepts tcp connections on both interfaces. How I can assure ...
14
votes
1answer
752 views

“ss” command in iproute package; why query slab table for timewait sockets?

Forgive me if this isn't the best forum for this question, but it seems more relevant to the kernel than to the programming itself. I'm writing a script that queries the system for open ports so that ...
15
votes
2answers
2k views

What is a socket?

Could someone explain to me what a socket is? I see it in many acronyms in context of SSL, etc. Also, why is it called a socket? Is it purely because it was what a name they invented? Or was it the ...