why there is no matchSubnet() for ipv6 address

[DinoStray]

For ipv4 address, I can use matchSubnet() checks whether the address matches a subnet.
But for ipv6, how can I do this?

I also asked this question in :

https://stackoverflow.com/questions/62129703/for-lib-pcapplusplus-why-there-is-no-matchsubnet-for-ipv6-address

[seladb]

That's a good point, this feature doesn't currently exist, probably because no one has asked for it 😄

Would you consider adding it?

[seladb]

@DinoStray please let me know if you'd consider implementing this feature

[DinoStray]

@DinoStray please let me know if you'd consider implementing this feature

Sorry, I go out for a weekend trip. OK, pleasure with that.
But first of all, maybe I should learn more about ipv6

[seladb]

Thanks, I really appreciate your help!

You can read about IPv6 subnet mask here: https://tools.ietf.org/id/draft-lubashev-ipv6-addr-mask-01.html https://docs.netgate.com/pfsense/en/latest/book/network/ipv6-subnets.html

[seladb]

hi @DinoStray , any progress on that?

[DinoStray]

Sorry it took me some time to understand some concepts.

For IPv4, we need subnet mask.

so the method should be:

bool matchSubnet(const IPv4Address& subnet, const IPv4Address& subnetMask) const;

But for IPv6, we only need prefix length.

so the method should be:

bool matchSubnet(const IPv6Address& subnet, uint8_t prefixLength) const;

Am I right? @seladb

[seladb]

Yes, that's correct. The prefixLength tells how many bytes to use in the mask

[DinoStray]

I committed a PR for this issue

[seladb]

Thanks! please take a look at my PR comments

[DinoStray]

I committed a new PR following your comments.