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In a normal subnet of 192.168.1.* with a subnet mask of 255.255.255.0, the broadcast address should be 192.168.1.255. I'm trying to ping my network using my this address without succes. Why?
Where can I find a program that will brodcast a ping or a TCP Port? If you answer me Nmap, please tell the command line or a page where I can find the information! Thank.
What are the devices on the network? Generally using ping 192.168.1.255 -t (windows) or ping 192.168.1.255 -b (linux) should work unless ping is surpressed by router/switch/firewall.
And I'm not sure what you mean by broadcasting a ping or a TCP port. No TCP port can be broadcast so to speak. If you mean broadcasting a ping to a TCP port, IIRC, ICMP is a protocol on it's own and doesn't go to a specific port.
Ping 192.168.1.255 -t doesn't work either. I get Request timed out. I'm sure that my Switch doesn't block me because I have a program that do a Broadcast and that work. I'm trying to make this program work across VPN/Subnet and I'm unable so that why I'm looking for a utilites to do the same to locate the problem. The first step is to be find that program and make it work since my own subnet.
Have you run arp -a after the ping broadcast just to see if anything is actually being picked up after the fact? What kind of VPN is it? If it's a router-to-router setup, is it possible that one is blocking it? (my gut says something is blocking). Have you done a sniff of the network to see what/where packets are going and other activity that might be going on?
I'm pretty sure the VPN is blocking the broadcast. But I'm also sure that the broadcast is NOT block in my local subnet. Right now, I only want to be able to broadcast a ping or an UDP port inside my local subnet. After I'm able to do that, I'll attack myself to get the broadcast work across the VPN.
192.168.1.255 is a subnet broadcast. 255.255.255.255 is a broadcast address.
What OSs are there on that subnet? If it consists of windows only machines you'll never get a response. A Windows machine will not respond to a broadcast ping (by default). A linux machine may respond depending on the configuration (read: distro). Both have the option to turn it on or off.
Please note: You should make sure it's turned off. If it's turned on your network is vulnerable to a smurf attack.
As for nmap, try nmap -sP -vv -n 192.168.1.255
Try and send a SYN packet to 192.168.1.255/port 80 i.e. and see what happens..not sure what should though..Quote:
nmap -sS -vv -n -p80 -P0 192.168.1.255 should do the trick.
Can I broadcast over a UDP port? Will I get answer from service listening over that port?
I try doing a nmap -sU -p***** -v -P0 255.255.255.255
Quote:
Starting nmap 3.75 ( http://www.insecure.org/nmap ) at 2004-11-04 10:31 Eastern
Standard Time
Initiating UDP Scan against 255.255.255.255 [1 port] at 10:31
The UDP Scan took 2.06s to scan 1 total ports.
Host 255.255.255.255 appears to be up ... good.
Interesting ports on 255.255.255.255:
PORT STATE SERVICE
*****/udp open|filtered unknown
Nmap run completed -- 1 IP address (1 host up) scanned in 2.235 seconds
I would have thought that it would have been more like nmap -sS -vv -n -p80 -P0 192.168.1.0/24 sent out over the network rather than the broadcast to get all hosts to respond to a probe of port 80.Quote:
nmap -sS -vv -n -p80 -P0 192.168.1.255
Perhaps someone should get TH13's opinion? ;)
If there's something listening, it's highly probably that it'll respond.
It might be a good idea to keep a sniffer running when doing these scans.
It'll give you more detailed information on what's happening.
That would scan all addresses in the 192.168.1.0-192.168.1.255 range.Quote:
nmap -sS -vv -n -p80 -P0 192.168.1.0/24
It would be the same as using 192.168.1.*
I try those command and both work
nmap -sU -p42508 -P0 -S 192.168.1.18 -vv 192.168.1.1-10
nmap -sU -p42508 -P0 -S 192.168.1.18 -vv 192.168.2.50-65
Does I need the answer to this question : Can I broadcast over a UDP port? If yes, how?
What I find stranage also is doing a nmap -sU -p42508 -P0 -S 192.168.1.18 -vv 255.255.255.255 only return me one host. This, I don't understand at all.