IP verification regex...

[jconner]

I know somebody has had to have written one. Instead of re-inventing the wheel, I was wondering if someone had one they could pass along to me or know of where I can get one.

Purpose? Im asking the user for an IP address. I want to verify that what they put in is a valid IP. Im doing this via ereg()

TIA! - Jim

[andreas]

$answer = "This is easy" // hehe...

if(ereg("^{[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}$",} $ip_nummber))
print "Jupp... this is a valid IP nummber";
else
print "Damn you trying to give me a non valid ip number!!!";

hehe.. this should do the trick..

Andreas

[[deleted]]

Actually, it doesn't do the trick. 🙂

This only checks to see if the format is of
one-three digits with points in between.

so 999.999.999.999 would qualify.

I posted a "better" one a little while back, can't find it right now though 🙁

[jc94062]

Well, what are you trying to do with this, cause someone could put in 62.49.146.12, seems valid, doubt it actually exists (timed out my ping anyways) unless my random numbers arn't random 🙂

[[deleted]]

There is a subtile difference between a "valid" IP number and an "existing" IP number.
62.49.146.12 is valid, but that does not (have to) mean that there is a server somewhere actually using it.

Luckily there still are IP numbers that are not taken by servers, of the internet would have reached it's limit already.. :-)

[Anon]

All I need to do is make sure that it is a valid IP address. Its ok if the IP is not in use. My script is only going to take that IP and do some math with it.

[Anon]

Yeah, this won't do. The regex must make sure that the octets stay within the 255 limit. In fact, I will have checks to make sure that the IP given stays outside of multicast and private IP address blocks but I need to start with validating the IP first.

Btw, I appreciate everyones' input on this.