Drop packets destined to real0

Summary: Details in T184429066 tl;dr If packet is destined to vip, but if the reals aren't initialized, drop the packet, instead of sending it to empty address Reviewed By: frankfeir Differential Revision: D58979009 fbshipit-source-id: 7d968877365765539eb8a7e7b5772fd3f9646105
facebookincubator · Jun 25, 2024 · 80f8d87 · 80f8d87
1 parent e50d765
commit 80f8d87
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Showing 5 changed files with 34 additions and 0 deletions.
diff --git a/katran/lib/bpf/balancer.bpf.c b/katran/lib/bpf/balancer.bpf.c
@@ -152,6 +152,7 @@ __attribute__((__always_inline__)) static inline bool get_packet_dst(
       // Real ids start from 1, so we don't map the id 0 to any real. This
       // is likely to happen if the ch ring for a vip is uninitialized.
       increment_ch_drop_real_0();
+      return false;
     }
   }
   pckt->real_index = key;

diff --git a/katran/lib/testing/KatranGueTestFixtures.h b/katran/lib/testing/KatranGueTestFixtures.h
@@ -337,6 +337,23 @@ const std::vector<::katran::PacketAttributes> gueTestFixtures = {
      .expectedReturnValue = "XDP_TX",
      .expectedOutputPacket = "AADerb6vAgAAAAAAht1gAAAAAC4RQPwAIwcAAAAAAAAAAAAAEzf8AAAAAAAAAAAAAAAAAAACe0MmngAu/TFFAAAmAAEAAEARrSfAqAEqCsgBBXppAbsAEm5CAIADBEQAAAAAQA=="
     },
+    // 35
+    {// Ether(src="0x1", dst="0x2")/IP(src="192.168.1.1",
+     // dst="10.200.1.99")/TCP(sport=31337, dport=80, flags="A")/"katran test pkt"
+     .inputPacket = "AgAAAAAAAQAAAAAACABFAAA3AAEAAEAGrOzAqAEBCsgBY3ppAFAAAAAAAAAAAFAQIAAnggAAa2F0cmFuIHRlc3QgcGt0",
+     .description = "packet to TCP based v4 VIP that is not initialzed",
+     .expectedReturnValue = "XDP_DROP",
+     .expectedOutputPacket = "AgAAAAAAAQAAAAAACABFAAA3AAEAAEAGrOzAqAEBCsgBY3ppAFAAAAAAAAAAAFAQIAAnggAAa2F0cmFuIHRlc3QgcGt0"
+    },
+    // 36
+    {// Ether(src="0x1", dst="0x2")/IPv6(src="fc00:2::1",
+     // dst="fc00:1::11")/UDP(sport=31337, dport=80)/"katran test pkt"
+     .inputPacket = "AgAAAAAAAQAAAAAAht1gAAAAABMRQPwAAAIAAAAAAAAAAAAAAAH8AAABAAAAAAAAAAAAAAARemkAUAATUc5rYXRyYW4gdGVzdA==",
+     .description = "packet to UDP based v6 VIP that is not initialized",
+     .expectedReturnValue = "XDP_DROP",
+     .expectedOutputPacket = "AgAAAAAAAQAAAAAAht1gAAAAABMRQPwAAAIAAAAAAAAAAAAAAAH8AAABAAAAAAAAAAAAAAARemkAUAATUc5rYXRyYW4gdGVzdA=="
+    },
+
 };
 
 } // namespace testing

diff --git a/katran/lib/testing/KatranTestProvision.cpp b/katran/lib/testing/KatranTestProvision.cpp
@@ -192,6 +192,18 @@ void prepareOptionalLbData(katran::KatranLb& lb) {
   lb.modifyReal("10.0.0.6", kLocalReal);
 }
 
+void prepareVipUninitializedLbData(katran::KatranLb& lb) {
+  katran::VipKey vip;
+  vip.address = "10.200.1.99";
+  vip.port = kVipPort;
+  vip.proto = kTcp;
+  lb.addVip(vip);
+
+  vip.address = "fc00:1::11";
+  vip.proto = kUdp;
+  lb.addVip(vip);
+}
+
 void preparePerfTestingLbData(katran::KatranLb& lb) {
   for (auto& dst : kReals) {
     lb.addInlineDecapDst(dst);

diff --git a/katran/lib/testing/KatranTestProvision.h b/katran/lib/testing/KatranTestProvision.h
@@ -138,6 +138,8 @@ void prepareLbData(katran::KatranLb& lb);
 
 void prepareOptionalLbData(katran::KatranLb& lb);
 
+void prepareVipUninitializedLbData(katran::KatranLb& lb);
+
 void preparePerfTestingLbData(katran::KatranLb& lb);
 } // namespace testing
 } // namespace katran
diff --git a/katran/lib/testing/katran_tester.cpp b/katran/lib/testing/katran_tester.cpp
@@ -286,6 +286,8 @@ void runTestsFromFixture(
     katran::BpfTester& tester,
     KatranTestParam& testParam) {
   prepareLbData(lb);
+  prepareVipUninitializedLbData(lb);
+
   tester.resetTestFixtures(testParam.testData);
   auto prog_fd = lb.getKatranProgFd();
   tester.setBpfProgFd(prog_fd);