Nmap Unusable

pxumsgdxpcvjm · 06-08-2008, 06:06 AM

Recently I upgraded to Slackware 12.1. Other then a few minor problems, the install and setup went smoothly. I just installed Nmap for it tonight. Compiled from source since I wanted to use the latest version but for some reason I can't get it working in a unusable state. Here's the commands I'm using...

Code:

user@Computer:~$ nmap 192.168.1.2 -v

Starting Nmap 4.65 ( http://nmap.org ) at 2008-06-08 22:53 NZST
Initiating Ping Scan at 22:53
Scanning 192.168.1.2 [1 port]
Completed Ping Scan at 22:53, 2.01s elapsed (1 total hosts)
Read data files from: /usr/local/share/nmap
Note: Host seems down. If it is really up, but blocking our ping probes, try -PN
Nmap done: 1 IP address (0 hosts up) scanned in 2.169 seconds
user@Computer:~$ nmap 192.168.1.2 -v -PN

Starting Nmap 4.65 ( http://nmap.org ) at 2008-06-08 22:53 NZST
Initiating Ping Scan at 22:53
Scanning 192.168.1.2 [0 ports]
Completed Ping Scan at 22:53, 0.00s elapsed (1 total hosts)
Read data files from: /usr/local/share/nmap
Note: Host seems down. If it is really up, but blocking our ping probes, try -PN
Nmap done: 1 IP address (0 hosts up) scanned in 0.221 seconds
user@Computer:~$ ping 192.168.1.2
PING 192.168.1.2 (192.168.1.2) 56(84) bytes of data.
64 bytes from 192.168.1.2: icmp_seq=1 ttl=128 time=1.38 ms
64 bytes from 192.168.1.2: icmp_seq=2 ttl=128 time=1.72 ms
64 bytes from 192.168.1.2: icmp_seq=3 ttl=128 time=1.17 ms
64 bytes from 192.168.1.2: icmp_seq=4 ttl=128 time=1.15 ms

--- 192.168.1.2 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 2999ms
rtt min/avg/max/mdev = 1.151/1.358/1.724/0.232 ms

It's making no sense to me. I didn't have this problem at all with Slackware 12.0. Anyway, I tried again using the root account which worked. I figured that this was just some security layer or something added to Slackware 12.1 but to my surprise, I'm able to use Nmap to connect to all others computers on my network, just not 192.168.1.2 for some reason. Anyone know what could be the issue at hand here?

Thanks to any replies.

MS3FGX · 06-08-2008, 07:22 AM

I can't imagine that is a Slackware-specific issue, but rather some sort of a bug. Have you tried building an older version and seeing if the problem persists there as well?

I would also suggest you use the official Slackbuild for nmap which will let you build from source to an installable Slackware package. Even if it doesn't clear up the issue you are having specifically, at the very least it will make building and testing new versions easier.

allend · 06-08-2008, 07:53 AM

As nmap manipulates the privileged ports (1-1024) it requires root privileges. You will need to run nmap as root.

From man nmap:

Quote:

On Unix boxes, only the privileged user root is generally able to send and receive raw TCP packets. For unprivileged users, a workaround is automatically employed whereby the connect() system call is initiated against each target port.