pf: NAT rule logs its own NAT action, not PF_PASS

[franco_opnsense.org]

Summary

Prior to 948e8413 the NAT log was implicitly
using r->action, but it was changed to an explicit
PF_PASS. Restore the correct behaviour by
explicitly passing nr->action.

Add a test for it while here.

[kp]

Shall we finish D47658 before we move on to other issues?

[franco_opnsense.org]

D47658 is on hold as I struggle to understand why the code discussed there is not covered by existing tests and how to actually trigger it (it should easily panic after all but the code is never hit).

[kp]

In D47777#1089450, @franco_opnsense.org wrote:

D47658 is on hold as I struggle to understand why the code discussed there is not covered by existing tests and how to actually trigger it (it should easily panic after all but the code is never hit).

Then please update that review to state that there.

As for this one, let's start with the commit message. Try to explain both the problem and then justify chosen solution. 'fix regression' does not enlighten.

[franco_opnsense.org]

I changed the summary.

I'll gladly update the other review and I also appreciate a response to my last comment there.

[kp]

In D47777#1089452, @franco_opnsense.org wrote:

I changed the summary.

Please do try to *explain* the problem. "Fixes a regression" does not do this.

[franco_opnsense.org]

Feel free to make a different suggestion. I've long been under the impressions explaining one liners is not the scope of a commit message and the tests should make this rather clear as requested in previous discussions.