Implements the new quorum intersection checker

- Rust bridge and wrapper for `FbasAnalyzer` (stellar/stellar-quorum-analyzer)
- A new adaptor class `RustQuorumCheckerAdaptor` that wraps the Rust calls
- Async interruption handling
- A new config flag `USE_QUORUM_INTERSECTION_CHECKER_V2` to toggle between old and new solver
- Update all tests

Builds/VisualStudio/stellar-core.vcxproj

@@ -521,6 +521,7 @@ exit /b 0
     <ClCompile Include="..\..\src\herder\PendingEnvelopes.cpp" />
     <ClCompile Include="..\..\src\herder\QuorumIntersectionCheckerImpl.cpp" />
     <ClCompile Include="..\..\src\herder\QuorumTracker.cpp" />
+    <ClCompile Include="..\..\src\herder\RustQuorumCheckerAdaptor.cpp" />
     <ClCompile Include="..\..\src\herder\SurgePricingUtils.cpp" />
     <ClCompile Include="..\..\src\herder\test\HerderTests.cpp" />
     <ClCompile Include="..\..\src\herder\test\PendingEnvelopesTests.cpp" />
@@ -976,6 +977,7 @@ exit /b 0
     <ClInclude Include="..\..\src\herder\QuorumIntersectionChecker.h" />
     <ClInclude Include="..\..\src\herder\QuorumIntersectionCheckerImpl.h" />
     <ClInclude Include="..\..\src\herder\QuorumTracker.h" />
+    <ClInclude Include="..\..\src\herder\RustQuorumCheckerAdaptor.h" />
     <ClInclude Include="..\..\src\herder\SurgePricingUtils.h" />
     <ClInclude Include="..\..\src\herder\test\TestTxSetUtils.h" />
     <ClInclude Include="..\..\src\herder\TransactionQueue.h" />

Builds/VisualStudio/stellar-core.vcxproj.filters

@@ -696,6 +696,9 @@
     <ClCompile Include="..\..\src\herder\QuorumTracker.cpp">
       <Filter>herder</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\herder\RustQuorumCheckerAdaptor.cpp">
+      <Filter>herder</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\src\herder\SurgePricingUtils.cpp">
       <Filter>herder</Filter>
     </ClCompile>
@@ -1892,6 +1895,9 @@
     <ClInclude Include="..\..\src\herder\QuorumTracker.h">
       <Filter>herder</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\herder\RustQuorumCheckerAdaptor.h">
+      <Filter>herder</Filter>
+    </ClInclude>
     <ClInclude Include="..\..\src\herder\SurgePricingUtils.h">
       <Filter>herder</Filter>
     </ClInclude>

docs/versioning-soroban.md

@@ -139,7 +139,7 @@ We are leveraging Rust's support for linking together multiple copies of "the
 same" library (soroban) with different versions, but we are doing so somewhat
 against the grain of how cargo normally wants to do it.
 
-Do do this "the normal way", we would just list the different versions of the
+To do this "the normal way", we would just list the different versions of the
 soroban crate in `Cargo.toml`, and then when we built it cargo would attempt to
 resolve all the dependencies and transitive-dependencies of all those soroban
 versions into a hopefully-minimal set of crates and download, compile and link
@@ -165,7 +165,7 @@ This has one minor and one major problem:
      p22 module on foo 0.1, cargo will bump _both_ to foo 0.2, which _changes_
      the semantics of the p22 module.
 
-       - We initially though a way out of this is to add redundant exact-version
+       - We initially thought a way out of this is to add redundant exact-version
          dependencies (like `foo = "=0.2"`) to `Cargo.toml` for
          `soroban-env-host` but there turn out to be both a minor and a major
          problem with that too.

src/herder/HerderImpl.cpp

@@ -13,6 +13,7 @@
 #include "herder/HerderUtils.h"
 #include "herder/LedgerCloseData.h"
 #include "herder/QuorumIntersectionChecker.h"
+#include "herder/RustQuorumCheckerAdaptor.h"
 #include "herder/TxSetFrame.h"
 #include "herder/TxSetUtils.h"
 #include "ledger/LedgerManager.h"
@@ -261,6 +262,13 @@ HerderImpl::newSlotExternalized(bool synchronous, StellarValue const& value)
     safelyProcessSCPQueue(synchronous);
 }
 
+void
+HerderImpl::interrupt_quorum_checker()
+{
+    mLastQuorumMapIntersectionState.mInterruptFlag = true;
+    mLastQuorumMapIntersectionState.mInterrupt->fire();
+}
+
 void
 HerderImpl::shutdown()
 {
@@ -273,7 +281,7 @@ HerderImpl::shutdown()
         // avoid a long pause joining worker threads.
         CLOG_DEBUG(Herder,
                    "Shutdown interrupting quorum transitive closure analysis.");
-        mLastQuorumMapIntersectionState.mInterruptFlag = true;
+        interrupt_quorum_checker();
     }
     mTransactionQueue.shutdown();
     if (mSorobanTransactionQueue)
@@ -1883,7 +1891,7 @@ HerderImpl::checkAndMaybeReanalyzeQuorumMap()
             CLOG_DEBUG(Herder, "Transitive closure of quorum has "
                                "changed, interrupting existing "
                                "analysis.");
-            mLastQuorumMapIntersectionState.mInterruptFlag = true;
+            interrupt_quorum_checker();
         }
     }
     else
@@ -1897,33 +1905,76 @@ HerderImpl::checkAndMaybeReanalyzeQuorumMap()
         auto& cfg = mApp.getConfig();
         releaseAssert(threadIsMain());
         auto seed = gRandomEngine();
-        auto qic = QuorumIntersectionChecker::create(
-            qmap, cfg, mLastQuorumMapIntersectionState.mInterruptFlag, seed);
+
         auto ledger = trackingConsensusLedgerIndex();
         auto nNodes = qmap.size();
         auto& hState = mLastQuorumMapIntersectionState;
         auto& app = mApp;
-        auto worker = [curr, ledger, nNodes, qic, qmap, cfg, seed, &app,
-                       &hState] {
+        auto worker = [curr, ledger, nNodes, qmap, cfg, seed, &app, &hState] {
             try
             {
                 ZoneScoped;
-                bool ok = qic->networkEnjoysQuorumIntersection();
-                auto split = qic->getPotentialSplit();
+                bool useV2 = app.getConfig().USE_QUORUM_INTERSECTION_CHECKER_V2;
+                bool ok = false;
+                std::pair<std::vector<PublicKey>, std::vector<PublicKey>> split;
+                if (useV2)
+                {
+                    ok = RustQuorumCheckerAdaptor::
+                        networkEnjoysQuorumIntersection(
+                            qmap, cfg, *hState.mInterrupt, split);
+                }
+                else
+                {
+                    auto qic = QuorumIntersectionChecker::create(
+                        qmap, cfg, hState.mInterruptFlag, seed);
+                    ok = qic->networkEnjoysQuorumIntersection();
+                    split = qic->getPotentialSplit();
+                }
                 std::set<std::set<PublicKey>> critical;
                 if (ok)
                 {
                     // Only bother calculating the _critical_ groups if we're
                     // intersecting; if not intersecting we should finish ASAP
                     // and raise an alarm.
-                    critical = QuorumIntersectionChecker::
-                        getIntersectionCriticalGroups(
-                            qmap, cfg, hState.mInterruptFlag, seed);
+                    if (useV2)
+                    {
+                        auto cb =
+                            [&hState](
+                                QuorumIntersectionChecker::QuorumSetMap const&
+                                    qSetMap,
+                                std::optional<Config> const& config) -> bool {
+                            std::pair<std::vector<PublicKey>,
+                                      std::vector<PublicKey>>
+                                potential_split;
+                            return RustQuorumCheckerAdaptor::
+                                networkEnjoysQuorumIntersection(
+                                    qSetMap, config, *hState.mInterrupt,
+                                    potential_split);
+                        };
+                        critical = QuorumIntersectionChecker::
+                            getIntersectionCriticalGroups(qmap, cfg, cb);
+                    }
+                    else
+                    {
+                        auto cb =
+                            [&hState, seed](
+                                QuorumIntersectionChecker::QuorumSetMap const&
+                                    qSetMap,
+                                std::optional<Config> const& config) -> bool {
+                            auto checker = QuorumIntersectionChecker::create(
+                                qSetMap, config, hState.mInterruptFlag, seed,
+                                /*quiet=*/true);
+                            return checker->networkEnjoysQuorumIntersection();
+                        };
+                        critical = QuorumIntersectionChecker::
+                            getIntersectionCriticalGroups(qmap, cfg, cb);
+                    }
                 }
                 app.postOnMainThread(
                     [ok, curr, ledger, nNodes, split, critical, &hState] {
                         hState.mRecalculating = false;
                         hState.mInterruptFlag = false;
+                        hState.mInterrupt->reset();
                         hState.mNumNodes = nNodes;
                         hState.mLastCheckLedger = ledger;
                         hState.mLastCheckQuorumMapHash = curr;
@@ -1945,10 +1996,26 @@ HerderImpl::checkAndMaybeReanalyzeQuorumMap()
                     [&hState] {
                         hState.mRecalculating = false;
                         hState.mInterruptFlag = false;
+                        hState.mInterrupt->reset();
                         hState.mCheckingQuorumMapHash = Hash{};
                     },
                     "QuorumIntersectionChecker interrupted");
             }
+            catch (const RustQuorumCheckerError& e)
+            {
+                CLOG_DEBUG(Herder,
+                           "Quorum transitive closure analysis failed due to "
+                           "Rust solver error: {}",
+                           e.what());
+                app.postOnMainThread(
+                    [&hState] {
+                        hState.mRecalculating = false;
+                        hState.mInterruptFlag = false;
+                        hState.mInterrupt->reset();
+                        hState.mCheckingQuorumMapHash = Hash{};
+                    },
+                    "QuorumIntersectionChecker rust error");
+            }
         };
         mApp.postOnBackgroundThread(worker, "QuorumIntersectionChecker");
     }

src/herder/HerderImpl.h

@@ -9,6 +9,7 @@
 #include "herder/PendingEnvelopes.h"
 #include "herder/TransactionQueue.h"
 #include "herder/Upgrades.h"
+#include "rust/RustBridge.h"
 #include "util/Timer.h"
 #include "util/UnorderedMap.h"
 #include "util/XDROperators.h"
@@ -30,7 +31,7 @@ constexpr uint32 const SOROBAN_TRANSACTION_QUEUE_SIZE_MULTIPLIER = 2;
 class Application;
 class LedgerManager;
 class HerderSCPDriver;
-
+class InterruptGuard;
 /*
  * Is in charge of receiving transactions from the network.
  */
@@ -338,7 +339,13 @@ class HerderImpl : public Herder
         Hash mLastCheckQuorumMapHash{};
         Hash mCheckingQuorumMapHash{};
         bool mRecalculating{false};
+
+        // for v1 (QuorumIntersectionChecker)
         std::atomic<bool> mInterruptFlag{false};
+        // for v2 (rust quorum checker)
+        rust::Box<rust_bridge::quorum_checker::Interrupt> mInterrupt{
+            rust_bridge::quorum_checker::new_interrupt()};
+
         std::pair<std::vector<PublicKey>, std::vector<PublicKey>>
             mPotentialSplit{};
         std::set<std::set<PublicKey>> mIntersectionCriticalNodes{};
@@ -357,6 +364,8 @@ class HerderImpl : public Herder
     };
     QuorumMapIntersectionState mLastQuorumMapIntersectionState;
 
+    void interrupt_quorum_checker();
+
     State mState;
     void setState(State st);
 

src/herder/HerderUtils.cpp

@@ -3,10 +3,12 @@
 // of this distribution or at http://www.apache.org/licenses/LICENSE-2.0
 
 #include "herder/HerderUtils.h"
+#include "crypto/KeyUtils.h"
+#include "main/Config.h"
+#include "rust/RustVecXdrMarshal.h"
 #include "scp/Slot.h"
 #include "xdr/Stellar-ledger.h"
 #include <algorithm>
-#include <xdrpp/marshal.h>
 
 namespace stellar
 {
@@ -40,4 +42,50 @@ getStellarValues(SCPStatement const& statement)
 
     return result;
 }
+
+// Render `id` as a short, human readable string. If `cfg` has a value, this
+// function uses `cfg` to render the string. Otherwise, it returns the first 5
+// hex values `id`.
+std::string
+toShortString(std::optional<Config> const& cfg, NodeID const& id)
+{
+    if (cfg)
+    {
+        return cfg->toShortString(id);
+    }
+    else
+    {
+        return KeyUtils::toShortString(id).substr(0, 5);
+    }
+}
+
+QuorumIntersectionChecker::QuorumSetMap
+toQuorumIntersectionMap(QuorumTracker::QuorumMap const& qmap)
+{
+    QuorumIntersectionChecker::QuorumSetMap ret;
+    for (auto const& elem : qmap)
+    {
+        ret[elem.first] = elem.second.mQuorumSet;
+    }
+    return ret;
+}
+
+std::pair<std::vector<PublicKey>, std::vector<PublicKey>>
+toQuorumSplitNodeIDs(QuorumSplit& split)
+{
+    std::vector<NodeID> leftNodes;
+    leftNodes.reserve(split.left.size());
+    for (const auto& str : split.left)
+    {
+        leftNodes.push_back(KeyUtils::fromStrKey<NodeID>(std::string(str)));
+    }
+    std::vector<NodeID> rightNodes;
+    rightNodes.reserve(split.right.size());
+    for (const auto& str : split.right)
+    {
+        rightNodes.push_back(KeyUtils::fromStrKey<NodeID>(std::string(str)));
+    }
+    return std::make_pair(std::move(leftNodes), std::move(rightNodes));
+}
+
 }