BGP: set received from IP on import

[dhalperi]

Cleaner than trying to set it on export, which we have to get right across lots
of different paths. Also resolves issues with IBGP routes sometimes being sent
too far.

Fix #6490

[batfish-bot]

This change is 

[dhalperi]

Reviewable status: 0 of 10 files reviewed, 2 unresolved discussions (waiting on @dhalperi)

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projects/batfish/src/main/java/org/batfish/dataplane/protocols/BgpProtocolHelper.java, line 108 at r1 (raw file):

Quoted 14 lines of code…

    if (route.getCommunities().getCommunities().contains(StandardCommunity.NO_ADVERTISE)) {
      return null;
    }
    // Do not export route if its AS path contains the remote peer's AS and local peer has not set
    // getAllowRemoteOut
    if (sessionProperties.isEbgp()
        && route.getAsPath().containsAs(sessionProperties.getTailAs())
        && !af.getAddressFamilyCapabilities().getAllowRemoteAsOut()) {
      return null;
    }
    // Do not export if route has NO_EXPORT community and this is a true ebgp session
    if (route.getCommunities().getCommunities().contains(StandardCommunity.NO_EXPORT)
        && sessionProperties.isEbgp()
        && sessionProperties.getConfedSessionType() != ConfedSessionType.WITHIN_CONFED) {

revert

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projects/batfish/src/main/java/org/batfish/representation/cumulus/CumulusConversions.java, line 822 at r1 (raw file):

        boolean nextHopSelfAll = firstNonNull(ipv4af.getNextHopSelfAll(), Boolean.FALSE);
        if (!nextHopSelfAll) {
          nextHopSelf = false;

revert

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projects/batfish/src/test/java/org/batfish/dataplane/ibdp/BgpNextHopUnchangedTest.java, line 177 at r1 (raw file):

                        .build()
                        .getName())
                .setRouteReflectorClient(!ebgp)

FYI This is the only non-trivial test change. Had to make the middle router a reflector so it actually does reflect routes to the third router in the chain.

[progwriter]

Reviewed 8 of 10 files at r1, 5 of 6 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved

[codecov]

Codecov Report

Merging #6501 (0174588) into master (1d829e9) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##             master    #6501   +/-   ##
=========================================
  Coverage     73.31%   73.31%           
- Complexity    35512    35517    +5     
=========================================
  Files          2824     2824           
  Lines        143511   143513    +2     
  Branches      17337    17337           
=========================================
+ Hits         105216   105220    +4     
- Misses        29960    29961    +1     
+ Partials       8335     8332    -3     

Impacted Files	Coverage Δ	Complexity Δ
.../src/main/java/org/batfish/datamodel/BgpRoute.java	83.18% <ø> (ø)	24.00 <0.00> (ø)
.../org/batfish/dataplane/ibdp/BgpRoutingProcess.java	81.98% <100.00%> (+0.04%)	130.00 <0.00> (ø)
...batfish/dataplane/protocols/BgpProtocolHelper.java	94.65% <100.00%> (+0.62%)	45.00 <0.00> (-1.00)	⬆️
...tfish/representation/cisco/CiscoConfiguration.java	86.28% <0.00%> (-0.14%)	502.00% <0.00%> (-1.00%)
...java/org/batfish/common/topology/TopologyUtil.java	92.95% <0.00%> (+0.05%)	154.00% <0.00%> (+4.00%)
...ar/cumulus_frr/CumulusFrrConfigurationBuilder.java	74.48% <0.00%> (+0.15%)	165.00% <0.00%> (+1.00%)
...ish/representation/cumulus/CumulusConversions.java	91.75% <0.00%> (+0.36%)	190.00% <0.00%> (+2.00%)

[dhalperi]

a discussion (no related file):
Working: Self-merge only.

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