Comment on GoOn
FauxPseudo@lemmy.world 11 months ago
Ok. This covers every ipv6 and ipv4 address.
“^\s*((([0-9A-Fa-f]{1,4}:){7}([0-9A-Fa-f]{1,4}|:))|(([0-9A-Fa-f]{1,4}:){6}(:[0-9A-Fa-f]{1,4}|((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3})|:))|(([0-9A-Fa-f]{1,4}:){5}(((:[0-9A-Fa-f]{1,4}){1,2})|:((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3})|:))|(([0-9A-Fa-f]{1,4}:){4}(((:[0-9A-Fa-f]{1,4}){1,3})|((:[0-9A-Fa-f]{1,4})?:((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}))|:))|(([0-9A-Fa-f]{1,4}:){3}(((:[0-9A-Fa-f]{1,4}){1,4})|((:[0-9A-Fa-f]{1,4}){0,2}:((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}))|:))|(([0-9A-Fa-f]{1,4}:){2}(((:[0-9A-Fa-f]{1,4}){1,5})|((:[0-9A-Fa-f]{1,4}){0,3}:((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}))|:))|(([0-9A-Fa-f]{1,4}:){1}(((:[0-9A-Fa-f]{1,4}){1,6})|((:[0-9A-Fa-f]{1,4}){0,4}:((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}))|:))|(:(((:[0-9A-Fa-f]{1,4}){1,7})|((:[0-9A-Fa-f]{1,4}){0,5}:((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}))|:)))(%.+)?\s*$”
Please don’t. Use regex to find something that looks like an IP then build a real parser. This is madness
Just parse [0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3} using regex (for v4) and then have some code check that all the octets are valid (and store the IP as a u32)
And dupe check. 0.0.0.0 and 000.000.000.000 may both be valid, but they resolve the same
Fuck that, if for whatever reason I’m writing an IP validator by hand I’m disallowing leading zeros. Parsers are very inconsistent, some will parse 010 as 10, others as 0o10 == 8 (you can try that right now with a POSIX ping). Talk about a footgun.
some will parse 010 as 10, others as 0o10 == 8
…and that’s me in the fetal position, thanks.
Definitely, tho if you store it as a u32 that is fixed magically. Because 1.2.3.4 and 1.02.003.04 both map to the same number.
What I mean by storing it as a u32 is to convert it to a number, similar to how the IP gets sent over the wire, so for v4:
octet[3] | octet[2] << 8 | octet[1] << 16 | octet[0] << 24
or in more human terms:
(fourth octet) + (first octet * 256^3) + (second octet * 256^2) + (third octet * 256)
Because 1.2.3.4 and 1.02.003.04 both map to the same number.
But 10.20.30.40 and 010.020.030.040 map to different numbers. It’s often best to reject IPv4 addresses with leading zeroes to avoid the decimal vs. octal ambiguity.
True enough for database or dictionary storage, but a lot of times things get implemented in arrays where you still wind up with two copies of the same uint32.
IPv6 was a mistake. We should have just added an addition octet
That would allow for like, 2 trillion devices? Feels like a bandaid, my dude. Next you’re gonna suggest a giant ice cube in the ocean once a year to stop global warming.
So add two more octets:
Moat companies will still just use something like 10.0.13.37.0.1
IPv6 is not made with internal networks in mind lol
And nuke the hurricanes
Hurricanes cannot cross the equator. The equator is an imaginary line, and hence has zero mass. We can end every hurricane using zero point zero energy (0.0).
ONCE AND FOR ALL
AND MY AXE!
You could follow this logic and add 2 alphanumeric digits before 4 numeric octets. E.g. xf.192.168.1.1
This would at least keep it looking like an IP and not a Mac address
Oh yeah, great, let’s change the fundamental protocol on which all the networks in the world are based. Now two third of the devices in the world crashed because you tried to ping 192.168.0.0.1
that WOULD be quite funny for the first second or 2…
Could have sped up adoption significantly.
They played us for absolute fools!
IPv
heared of ipv5?
Plus the MAC address
Made that joke in an interview once.
They didn’t think it was funny. Truly thought Regex was the solution to, but never the cause of, all problems.
Dodged a bullet
Holy hell yeah you did. Hour would you go about doing that in a single expression? A bunch of back references to figure out the country? What if that’s not included? Oy.
You wouldn’t. It’s not possible. Which is what I told them.
Some countries have addresses that are literally ‘Last house on the left by the Big Tree. Bumban(Neighborhood). NN (Country)’. Any US Centric validation would fail this but I assure you mail gets delivered just fine.
/.+(road|street).+/ resigns
It’s always a treat to debug a regex of that size.
I knew there would be someone with the regex.
You’re more of a pearl programmer than network engineer :P
.*
Technically, this one also matches everything:
*leaves*
YIj54yALOJxEsY20eU@lemm.ee 11 months ago
Lord have mercy