my lame attempt at a shell script...
Timothy Luoma
lists at tntluoma.com
Mon Jan 3 18:21:20 PST 2005
On Jan 3, 2005, at 6:28 PM, Eric F Crist wrote:
> A couple more questions, then I'm done. Promise.
>
> I need to verify whether or not there is an entry for grog_firewall_oif
> and grog_firewall_iif in /etc/rc.conf. If not, I want to exit with an
> error.
You want to check for either "grog_firewall_oif" or "grog_firewall_iif"
in /etc/rc.conf
egrep -v "^#" /etc/rc.conf |\
egrep -q "grog_firewall_oif | grog_firewall_iif" || (echo "$0" ; exit 1)
The first line says "skips the comment lines" (the ones that begin with
#)
> Also, a little more advanced, I need to pull information from an
> ifconfig output. I need to pull network numbers for both the internal
> interface, as well as external interface. For example,
>
> vr0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
> inet 192.168.1.5 netmask 0xffffff00 broadcast 192.168.1.255
> inet6 fe80::20e:a6ff:feb9:2d3d%vr0 prefixlen 64 scopeid 0x3
> ether 00:0e:a6:b9:2d:3d
> media: Ethernet autoselect (100baseTX <full-duplex>)
> status: active
>
> I don't actually need my own address, I need to be able to figure out
> that the system, based on the above output, is on the 192.168.1.0/24
> network. This will be input into my firewall rulesets.
>
> I imagine that there's a util or command around that can do this, or I
> can code out the math, but there's got to be an easier way.
How much can you assume? Will you know the interface? If so it's
fairly easy
ifconfig vr0 |\
tr '\012' ' ' |\
sed 's#.*inet ##; s# netmask.*##'
roughly translated:
line 1: give me the information for vr0 only
line 2: replace the end of line (\012) and replace them with a space
line 3: delete everything from the beginning of the line up to "inet "
and then delete everything from " netmask" to the end of the line
Put it into a variable
MY_IP=`ifconfig vr0 |\
tr '\012' ' ' |\
sed 's#.*inet ##; s# netmask.*##'`
TjL
More information about the freebsd-questions
mailing list