Add basic routing LPM tests.

[melifaro]

Summary

Add basic longest-prefix match tests for IPv4/IPv6.

Tests performs LPM checks based on the dataplane behaviour.
While it may be easier to use route -n get for some of the tests,
in fact it executes somewhat different codepath (rn_lookup() vs rn_match()).

In the future more tests will be added to cover both control plane
and dataplane lookups.

[lwhsu]

There are some non-rfc1918 IPs used in these cases. Are they necessary?

[kp]

In D24684#543497, @lwhsu wrote:

There are some non-rfc1918 IPs used in these cases. Are they necessary?

They're TEST-NET-2/3 documentation prefixes, so I think they're fine. Probably even better than RFC1918 private ranges.
I tend to use TEST-NET-1 in the pf tests.

[melifaro]

In D24684#543497, @lwhsu wrote:

There are some non-rfc1918 IPs used in these cases. Are they necessary?

Well, all these blocks are documentation prefixes from RFC5737.
Technically it can be converted to RFC1918 blocks, but I'm not sure what's the benefit.

Could you please clarify your concerns?

[lwhsu]

In D24684#543504, @melifaro wrote:

Could you please clarify your concerns?

Thanks for the information and no other concerns. I thought they were public IPs and got confused. Sorry for the noise.

[melifaro]

In D24684#543517, @lwhsu wrote:

In D24684#543504, @melifaro wrote:

Could you please clarify your concerns?

Thanks for the information and no other concerns. I thought they were public IPs and got confused. Sorry for the noise.

Np!
In fact, I use TEST-NET-3 pretty rarely so after looking into that revision (it was sitting locally for quite a while) I suspected that I indeed used public IP range :-)