tcpsnoop_example.txt [plain text]
The following is a demonstration of the tcpsnoop program.
Here we run tcpsnoop and wait for new TCP connections to be established,
# tcpsnoop
UID PID LADDR LPORT DR RADDR RPORT SIZE CMD
100 20892 192.168.1.5 36398 -> 192.168.1.1 79 54 finger
100 20892 192.168.1.5 36398 <- 192.168.1.1 79 66 finger
100 20892 192.168.1.5 36398 -> 192.168.1.1 79 54 finger
100 20892 192.168.1.5 36398 -> 192.168.1.1 79 56 finger
100 20892 192.168.1.5 36398 <- 192.168.1.1 79 54 finger
100 20892 192.168.1.5 36398 <- 192.168.1.1 79 606 finger
100 20892 192.168.1.5 36398 -> 192.168.1.1 79 54 finger
100 20892 192.168.1.5 36398 <- 192.168.1.1 79 54 finger
100 20892 192.168.1.5 36398 -> 192.168.1.1 79 54 finger
100 20892 192.168.1.5 36398 -> 192.168.1.1 79 54 finger
100 20892 192.168.1.5 36398 <- 192.168.1.1 79 54 finger
0 242 192.168.1.5 23 <- 192.168.1.1 54224 54 inetd
0 242 192.168.1.5 23 -> 192.168.1.1 54224 54 inetd
0 242 192.168.1.5 23 <- 192.168.1.1 54224 54 inetd
0 242 192.168.1.5 23 <- 192.168.1.1 54224 78 inetd
0 242 192.168.1.5 23 -> 192.168.1.1 54224 54 inetd
0 20893 192.168.1.5 23 -> 192.168.1.1 54224 57 in.telnetd
0 20893 192.168.1.5 23 <- 192.168.1.1 54224 54 in.telnetd
0 20893 192.168.1.5 23 -> 192.168.1.1 54224 78 in.telnetd
0 20893 192.168.1.5 23 <- 192.168.1.1 54224 57 in.telnetd
0 20893 192.168.1.5 23 -> 192.168.1.1 54224 54 in.telnetd
0 20893 192.168.1.5 23 <- 192.168.1.1 54224 54 in.telnetd
0 20893 192.168.1.5 23 -> 192.168.1.1 54224 60 in.telnetd
0 20893 192.168.1.5 23 <- 192.168.1.1 54224 63 in.telnetd
0 20893 192.168.1.5 23 -> 192.168.1.1 54224 54 in.telnetd
0 20893 192.168.1.5 23 <- 192.168.1.1 54224 60 in.telnetd
0 20893 192.168.1.5 23 -> 192.168.1.1 54224 60 in.telnetd
0 20893 192.168.1.5 23 <- 192.168.1.1 54224 60 in.telnetd
0 20893 192.168.1.5 23 -> 192.168.1.1 54224 72 in.telnetd
[...]
As new connections are made, each of the TCP packets are traced along with
the UID, PID and command name.
tcpsnoop has many options, for example here we use "-v" to print times,
# tcpsnoop -v
STRTIME UID PID LADDR LPORT DR RADDR RPORT SIZE CMD
2005 Jul 11 21:21:19 0 242 192.168.1.5 79 <- 192.168.1.1 49001 54 inetd
2005 Jul 11 21:21:19 0 242 192.168.1.5 79 -> 192.168.1.1 49001 54 inetd
2005 Jul 11 21:21:19 0 242 192.168.1.5 79 <- 192.168.1.1 49001 54 inetd
2005 Jul 11 21:21:19 0 242 192.168.1.5 79 <- 192.168.1.1 49001 56 inetd
2005 Jul 11 21:21:19 0 242 192.168.1.5 79 -> 192.168.1.1 49001 54 inetd
2005 Jul 11 21:21:19 0 23181 192.168.1.5 79 -> 192.168.1.1 49001 444 in.fingerd
2005 Jul 11 21:21:19 0 23181 192.168.1.5 79 -> 192.168.1.1 49001 54 in.fingerd
2005 Jul 11 21:21:19 0 23181 192.168.1.5 79 <- 192.168.1.1 49001 54 in.fingerd
2005 Jul 11 21:21:19 0 23181 192.168.1.5 79 <- 192.168.1.1 49001 54 in.fingerd
2005 Jul 11 21:21:19 0 23181 192.168.1.5 79 <- 192.168.1.1 49001 54 in.fingerd
2005 Jul 11 21:21:19 0 23181 192.168.1.5 79 -> 192.168.1.1 49001 54 in.fingerd
[...]