From 94b362ceab12bd7fb2edd3973b9f64c256d76315 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Tue, 18 Mar 2025 19:21:03 +0700
Subject: [PATCH 01/23] test: removed on_feefilter that has never been
 implemented for Dash

---
 test/functional/test_framework/p2p.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/functional/test_framework/p2p.py b/test/functional/test_framework/p2p.py
index b56ef5ddc419..98a7981dc24d 100755
--- a/test/functional/test_framework/p2p.py
+++ b/test/functional/test_framework/p2p.py
@@ -578,7 +578,6 @@ def on_cfcheckpt(self, message): pass
     def on_cfheaders(self, message): pass
     def on_cfilter(self, message): pass
     def on_cmpctblock(self, message): pass
-    def on_feefilter(self, message): pass
     def on_filteradd(self, message): pass
     def on_filterclear(self, message): pass
     def on_filterload(self, message): pass

From 2322929ca3be6ceb3add6474a561a1bf431221b6 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Mon, 17 Mar 2025 14:14:47 +0700
Subject: [PATCH 02/23] feat!: add new protocol version PLATFORM_BAN_VERSION =
 70236

---
 src/version.h                         | 8 ++++++--
 test/functional/test_framework/p2p.py | 4 ++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/version.h b/src/version.h
index 025c3ea7beb6..4364d77b6400 100644
--- a/src/version.h
+++ b/src/version.h
@@ -11,7 +11,7 @@
  */
 
 
-static const int PROTOCOL_VERSION = 70237;
+static const int PROTOCOL_VERSION = 70238;
 
 //! initial proto version, to be increased after version/verack negotiation
 static const int INIT_PROTO_VERSION = 209;
@@ -20,7 +20,7 @@ static const int INIT_PROTO_VERSION = 209;
 static const int MIN_PEER_PROTO_VERSION = 70216;
 
 //! minimum proto version of masternode to accept in DKGs
-static const int MIN_MASTERNODE_PROTO_VERSION = 70237;
+static const int MIN_MASTERNODE_PROTO_VERSION = 70238;
 
 //! protocol version is included in MNAUTH starting with this version
 static const int MNAUTH_NODE_VER_VERSION = 70218;
@@ -64,9 +64,13 @@ static const int INCREASE_MAX_HEADERS2_VERSION = 70235;
 //! Behavior of QRINFO is changed in this protocol version
 static const int EFFICIENT_QRINFO_VERSION = 70236;
 
+
 //! cycleHash in isdlock message switched to using quorum's base block in this version
 static const int ISDLOCK_CYCLEHASH_UPDATE_VERSION = 70237;
 
+//! Introduced new p2p message platform pose BAN
+static const int PLATFORM_BAN_VERSION = 70238;
+
 // Make sure that none of the values above collide with `ADDRV2_FORMAT`.
 
 #endif // BITCOIN_VERSION_H
diff --git a/test/functional/test_framework/p2p.py b/test/functional/test_framework/p2p.py
index 98a7981dc24d..c5d5fbfd398e 100755
--- a/test/functional/test_framework/p2p.py
+++ b/test/functional/test_framework/p2p.py
@@ -99,8 +99,8 @@
 # The minimum P2P version that this test framework supports
 MIN_P2P_VERSION_SUPPORTED = 60001
 # The P2P version that this test framework implements and sends in its `version` message
-# Version 70237 switched cycleHash in isdlock message to using quorum's base block
-P2P_VERSION = 70237
+# Version 70238 introduced platform PoSe ban (dip-0031)
+P2P_VERSION = 70238
 # The services that this test framework offers in its `version` message
 P2P_SERVICES = NODE_NETWORK | NODE_HEADERS_COMPRESSED
 # The P2P user agent string that this test framework sends in its `version` message

From 0f80a0285c05adc075638714b9c661c3ff60d342 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Tue, 11 Mar 2025 14:21:40 +0700
Subject: [PATCH 03/23] feat!: implementation of Platform PoSe Ban p2p message

---
 src/evo/deterministicmns.cpp | 20 +++++++-
 src/evo/deterministicmns.h   |  7 ++-
 src/llmq/dkgsession.cpp      |  8 +++-
 src/masternode/meta.cpp      | 25 ++++++++++
 src/masternode/meta.h        | 78 +++++++++++++++++++++++++++----
 src/net_processing.cpp       | 90 +++++++++++++++++++++++++++++++++++-
 src/node/chainstate.cpp      |  2 +-
 src/protocol.cpp             |  6 ++-
 src/protocol.h               |  2 +
 9 files changed, 220 insertions(+), 18 deletions(-)

diff --git a/src/evo/deterministicmns.cpp b/src/evo/deterministicmns.cpp
index 08468ca9c5b9..e9aa068ab97a 100644
--- a/src/evo/deterministicmns.cpp
+++ b/src/evo/deterministicmns.cpp
@@ -9,12 +9,13 @@
 #include <evo/providertx.h>
 #include <evo/simplifiedmns.h>
 #include <evo/specialtx.h>
-#include <index/txindex.h>
 
 #include <chainparams.h>
 #include <coins.h>
 #include <consensus/validation.h>
 #include <deploymentstatus.h>
+#include <index/txindex.h>
+#include <masternode/meta.h>
 #include <messagesigner.h>
 #include <node/blockstorage.h>
 #include <script/standard.h>
@@ -641,6 +642,23 @@ bool CDeterministicMNManager::ProcessBlock(const CBlock& block, gsl::not_null<co
         oldList = GetListForBlockInternal(pindex->pprev);
         diff = oldList.BuildDiff(newList);
 
+        // apply platform unban for platform revive too
+        for (int i = 1; i < (int)block.vtx.size(); i++) {
+            const CTransaction& tx = *block.vtx[i];
+            if (!tx.IsSpecialTxVersion() || tx.nType != TRANSACTION_PROVIDER_UPDATE_SERVICE) {
+                // only interested in revive transactions
+                continue;
+            }
+            const auto opt_proTx = GetTxPayload<CProUpServTx>(tx);
+            if (!opt_proTx) continue; // should not happen but does not matter
+
+            if (auto meta_info = m_mn_metaman.GetMetaInfo(opt_proTx->proTxHash, false);
+                !meta_info || !meta_info->SetPlatformBan(false, nHeight)) {
+                LogPrint(BCLog::LLMQ, "%s -- MN %s is failed to Platform revived at height %d\n", __func__,
+                         opt_proTx->proTxHash.ToString(), nHeight);
+            }
+        }
+
         m_evoDb.Write(std::make_pair(DB_LIST_DIFF, newList.GetBlockHash()), diff);
         if ((nHeight % DISK_SNAPSHOT_PERIOD) == 0 || pindex->pprev == m_initial_snapshot_index) {
             m_evoDb.Write(std::make_pair(DB_LIST_SNAPSHOT, newList.GetBlockHash()), newList);
diff --git a/src/evo/deterministicmns.h b/src/evo/deterministicmns.h
index 9c106c5fe941..17bcefbd4ffb 100644
--- a/src/evo/deterministicmns.h
+++ b/src/evo/deterministicmns.h
@@ -32,6 +32,7 @@ class CCoinsViewCache;
 class CEvoDB;
 class CSimplifiedMNList;
 class CSimplifiedMNListEntry;
+class CMasternodeMetaMan;
 class TxValidationState;
 
 extern RecursiveMutex cs_main;
@@ -626,6 +627,7 @@ class CDeterministicMNManager
     std::atomic<int> to_cleanup {0};
 
     CEvoDB& m_evoDb;
+    CMasternodeMetaMan& m_mn_metaman;
 
     std::unordered_map<uint256, CDeterministicMNList, StaticSaltedHasher> mnListsCache GUARDED_BY(cs);
     std::unordered_map<uint256, CDeterministicMNListDiff, StaticSaltedHasher> mnListDiffsCache GUARDED_BY(cs);
@@ -633,8 +635,9 @@ class CDeterministicMNManager
     const CBlockIndex* m_initial_snapshot_index GUARDED_BY(cs) {nullptr};
 
 public:
-    explicit CDeterministicMNManager(CEvoDB& evoDb) :
-        m_evoDb(evoDb)
+    explicit CDeterministicMNManager(CEvoDB& evoDb, CMasternodeMetaMan& mn_metaman) :
+        m_evoDb(evoDb),
+        m_mn_metaman(mn_metaman)
     {
     }
     ~CDeterministicMNManager() = default;
diff --git a/src/llmq/dkgsession.cpp b/src/llmq/dkgsession.cpp
index 2fb687772808..2c9e2e9b2218 100644
--- a/src/llmq/dkgsession.cpp
+++ b/src/llmq/dkgsession.cpp
@@ -492,11 +492,15 @@ void CDKGSession::VerifyConnectionAndMinProtoVersions(CConnman& connman) const
             m->badConnection = true;
             logger.Batch("%s does not have min proto version %d (has %d)", m->dmn->proTxHash.ToString(), MIN_MASTERNODE_PROTO_VERSION, it->second);
         }
-
-        if (m_mn_metaman.GetMetaInfo(m->dmn->proTxHash)->OutboundFailedTooManyTimes()) {
+        const auto meta_info = m_mn_metaman.GetMetaInfo(m->dmn->proTxHash);
+        if (meta_info->OutboundFailedTooManyTimes()) {
             m->badConnection = true;
             logger.Batch("%s failed to connect to it too many times", m->dmn->proTxHash.ToString());
         }
+        if (meta_info->IsPlatformBanned()) {
+            m->badConnection = true;
+            logger.Batch("%s is Platform PoSe banned", m->dmn->proTxHash.ToString());
+        }
     }
 }
 
diff --git a/src/masternode/meta.cpp b/src/masternode/meta.cpp
index 72a1370ad997..8bfdcc0d9452 100644
--- a/src/masternode/meta.cpp
+++ b/src/masternode/meta.cpp
@@ -41,6 +41,8 @@ UniValue CMasternodeMetaInfo::ToJson() const
     ret.pushKV("lastOutboundAttemptElapsed", now - lastOutboundAttempt.load());
     ret.pushKV("lastOutboundSuccess", lastOutboundSuccess.load());
     ret.pushKV("lastOutboundSuccessElapsed", now - lastOutboundSuccess.load());
+    ret.pushKV("platform_ban", m_platform_ban);
+    ret.pushKV("platform_ban_updated", m_platform_ban_height);
 
     return ret;
 }
@@ -125,8 +127,31 @@ std::vector<uint256> CMasternodeMetaMan::GetAndClearDirtyGovernanceObjectHashes(
     return vecTmp;
 }
 
+bool CMasternodeMetaMan::AlreadyHavePlatformBan(const uint256& inv_hash) const
+{
+    LOCK(cs);
+    return m_seen_platform_bans.contains(inv_hash);
+}
+
+std::optional<PlatformBanMessage> CMasternodeMetaMan::GetPlatformBan(const uint256& inv_hash) const
+{
+    LOCK(cs);
+    auto it = m_seen_platform_bans.find(inv_hash);
+    if (it == m_seen_platform_bans.end()) return std::nullopt;
+
+    return it->second;
+}
+
+void CMasternodeMetaMan::RememberPlatformBan(const uint256& inv_hash, PlatformBanMessage& msg)
+{
+    LOCK(cs);
+    m_seen_platform_bans.insert({inv_hash, msg});
+}
+
 std::string MasternodeMetaStore::ToString() const
 {
     LOCK(cs);
     return strprintf("Masternodes: meta infos object count: %d, nDsqCount: %d", metaInfos.size(), nDsqCount);
 }
+
+uint256 PlatformBanMessage::GetHash() const { return ::SerializeHash(*this); }
diff --git a/src/masternode/meta.h b/src/masternode/meta.h
index 72eb844bb159..96fc29fcfff7 100644
--- a/src/masternode/meta.h
+++ b/src/masternode/meta.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_MASTERNODE_META_H
 #define BITCOIN_MASTERNODE_META_H
 
+#include <bls/bls.h>
 #include <serialize.h>
 #include <sync.h>
 #include <threadsafety.h>
@@ -13,6 +14,7 @@
 #include <atomic>
 #include <map>
 #include <memory>
+#include <optional>
 #include <vector>
 
 class CConnman;
@@ -46,6 +48,9 @@ class CMasternodeMetaInfo
     std::atomic<int64_t> lastOutboundAttempt{0};
     std::atomic<int64_t> lastOutboundSuccess{0};
 
+    bool m_platform_ban GUARDED_BY(cs){false};
+    int m_platform_ban_height GUARDED_BY(cs){0};
+
 public:
     CMasternodeMetaInfo() = default;
     explicit CMasternodeMetaInfo(const uint256& _proTxHash) : proTxHash(_proTxHash) {}
@@ -55,22 +60,18 @@ class CMasternodeMetaInfo
         nMixingTxCount(ref.nMixingTxCount.load()),
         mapGovernanceObjectsVotedOn(ref.mapGovernanceObjectsVotedOn),
         lastOutboundAttempt(ref.lastOutboundAttempt.load()),
-        lastOutboundSuccess(ref.lastOutboundSuccess.load())
+        lastOutboundSuccess(ref.lastOutboundSuccess.load()),
+        m_platform_ban(ref.m_platform_ban),
+        m_platform_ban_height(ref.m_platform_ban_height)
     {
     }
 
     SERIALIZE_METHODS(CMasternodeMetaInfo, obj)
     {
         LOCK(obj.cs);
-        READWRITE(
-                obj.proTxHash,
-                obj.nLastDsq,
-                obj.nMixingTxCount,
-                obj.mapGovernanceObjectsVotedOn,
-                obj.outboundAttemptCount,
-                obj.lastOutboundAttempt,
-                obj.lastOutboundSuccess
-                );
+        READWRITE(obj.proTxHash, obj.nLastDsq, obj.nMixingTxCount, obj.mapGovernanceObjectsVotedOn,
+                  obj.outboundAttemptCount, obj.lastOutboundAttempt, obj.lastOutboundSuccess, obj.m_platform_ban,
+                  obj.m_platform_ban_height);
     }
 
     UniValue ToJson() const;
@@ -96,6 +97,24 @@ class CMasternodeMetaInfo
     int64_t GetLastOutboundAttempt() const { return lastOutboundAttempt; }
     void SetLastOutboundSuccess(int64_t t) { lastOutboundSuccess = t; outboundAttemptCount = 0; }
     int64_t GetLastOutboundSuccess() const { return lastOutboundSuccess; }
+    bool SetPlatformBan(bool is_banned, int height)
+    {
+        LOCK(cs);
+        if (height < m_platform_ban_height) {
+            return false;
+        }
+        if (height == m_platform_ban_height && !is_banned) {
+            return false;
+        }
+        m_platform_ban = is_banned;
+        m_platform_ban_height = height;
+        return true;
+    }
+    bool IsPlatformBanned() const
+    {
+        LOCK(cs);
+        return m_platform_ban;
+    }
 };
 using CMasternodeMetaInfoPtr = std::shared_ptr<CMasternodeMetaInfo>;
 
@@ -150,6 +169,40 @@ class MasternodeMetaStore
     std::string ToString() const;
 };
 
+/**
+ * Platform PoSe Ban are result in the node voting against the targeted evonode in all future DKG sessions until that targeted
+ *evonode has been successfully banned. Platform will initiate this ban process by passing relevant information to Core using RPC. See DIP-0031
+ *
+ * We use 2 main classes to manage Platform PoSe Ban
+ *
+ * PlatformBanMessage
+ * PlatformBanManager - a higher-level construct which store information about ban status
+ **/
+
+/**
+ * PlatformBanMessage - low-level constructs which contain the m_protx_hash, m_requested_height, m_quorum_hash and m_signature
+ */
+class PlatformBanMessage
+{
+public:
+    uint256 m_protx_hash;
+    int32_t m_requested_height{0};
+    uint256 m_quorum_hash;
+    CBLSSignature m_signature;
+
+    PlatformBanMessage() = default;
+
+    SERIALIZE_METHODS(PlatformBanMessage, obj)
+    {
+        READWRITE(obj.m_protx_hash, obj.m_requested_height, obj.m_quorum_hash);
+        if (!(s.GetType() & SER_GETHASH)) {
+            READWRITE(CBLSSignatureVersionWrapper(const_cast<CBLSSignature&>(obj.m_signature), false));
+        }
+    }
+
+    uint256 GetHash() const;
+};
+
 class CMasternodeMetaMan : public MasternodeMetaStore
 {
 private:
@@ -160,6 +213,7 @@ class CMasternodeMetaMan : public MasternodeMetaStore
     bool is_valid{false};
 
     std::vector<uint256> vecDirtyGovernanceObjectHashes GUARDED_BY(cs);
+    std::map<uint256, PlatformBanMessage> m_seen_platform_bans GUARDED_BY(cs);
 
 public:
     explicit CMasternodeMetaMan();
@@ -181,6 +235,10 @@ class CMasternodeMetaMan : public MasternodeMetaStore
     void RemoveGovernanceObject(const uint256& nGovernanceObjectHash);
 
     std::vector<uint256> GetAndClearDirtyGovernanceObjectHashes();
+
+    bool AlreadyHavePlatformBan(const uint256& inv_hash) const;
+    std::optional<PlatformBanMessage> GetPlatformBan(const uint256& inv_hash) const;
+    void RememberPlatformBan(const uint256& inv_hash, PlatformBanMessage& msg);
 };
 
 #endif // BITCOIN_MASTERNODE_META_H
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 8f64d634a3b5..ac7faa78fb6e 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -37,6 +37,7 @@
 #include <util/check.h>
 #include <util/system.h>
 #include <util/strencodings.h>
+#include <util/underlying.h>
 #include <util/trace.h>
 
 #include <algorithm>
@@ -735,6 +736,9 @@ class PeerManagerImpl final : public PeerManager
                                const std::vector<CBlockHeader>& headers,
                                bool via_compact_block)
         EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex);
+    [[nodiscard]] MessageProcessingResult ProcessPlatformBanMessage(NodeId from, std::string_view msg_type, CDataStream& vRecv)
+        EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex);
+
     /** Various helpers for headers processing, invoked by ProcessHeadersMessage() */
     /** Deal with state tracking and headers sync for peers that send the
      * occasional non-connecting header (this can happen due to BIP 130 headers
@@ -2281,6 +2285,8 @@ bool PeerManagerImpl::AlreadyHave(const CInv& inv)
                 (m_cj_ctx->queueman && m_cj_ctx->queueman->HasQueue(inv.hash)) ||
 #endif // ENABLE_WALLET
                 (m_active_ctx && m_active_ctx->cj_server->HasQueue(inv.hash));
+    case MSG_PLATFORM_BAN:
+        return m_mn_metaman.AlreadyHavePlatformBan(inv.hash);
     }
 
 
@@ -2894,6 +2900,13 @@ void PeerManagerImpl::ProcessGetData(CNode& pfrom, Peer& peer, const std::atomic
                 push = true;
             }
         }
+        if (!push && inv.type == MSG_PLATFORM_BAN) {
+            auto opt_platform_ban = m_mn_metaman.GetPlatformBan(inv.hash);
+            if (opt_platform_ban.has_value()) {
+                m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::PLATFORMBAN, *opt_platform_ban));
+                push = true;
+            }
+        }
 
         if (!push) {
             vNotFound.push_back(inv);
@@ -3524,6 +3537,81 @@ void PeerManagerImpl::PostProcessMessage(MessageProcessingResult&& result, NodeI
     }
 }
 
+MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId from, std::string_view msg_type, CDataStream& vRecv)
+{
+    if (msg_type != NetMsgType::PLATFORMBAN) return {};
+
+    // Do nothing if node is out of sync
+    if (!m_mn_sync.IsBlockchainSynced()) {
+        return {};
+    }
+
+    PlatformBanMessage ban_msg;
+    vRecv >> ban_msg;
+
+    const uint256 hash = ban_msg.GetHash();
+
+    LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s height: %d peer=%d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_requested_height, from);
+
+    MessageProcessingResult ret{};
+    const auto list = Assert(m_dmnman)->GetListAtChainTip();
+    auto dmn = list.GetMN(ban_msg.m_protx_hash);
+    if (!dmn) {
+        // small P2P penalty (1), as the evonode may have very recently been removed
+        ret.m_error = MisbehavingError{1};
+        return ret;
+    }
+    if (dmn->nType != MnType::Evo) {
+        // Ban node, P2P penalty (100) if protx_hash is associated with a regular node not an evonode
+        LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s unexpected type of node\n", hash.ToString(), ban_msg.m_protx_hash.ToString());
+        ret.m_error = MisbehavingError{100};
+        return ret;
+    }
+    constexpr int day_of_blocks = 576;
+    int tipHeight = WITH_LOCK(cs_main, return m_chainman.ActiveChainstate().m_chain.Height());
+    if (tipHeight < ban_msg.m_requested_height || tipHeight - day_of_blocks > ban_msg.m_requested_height) {
+        // m_requested_height is inside the range [TipHeight - 576 - 5, TipHeight + 5]
+        LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s unexpected height: %d tip: %d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_requested_height, tipHeight);
+        if (tipHeight + 5 < ban_msg.m_requested_height || tipHeight - day_of_blocks - 5 > ban_msg.m_requested_height) {
+            // m_requested_height is outside the range [TipHeight - 576 - 5, TipHeight + 5]
+            ret.m_error = MisbehavingError{10};
+            return ret;
+        }
+        ret.m_error = MisbehavingError{1};
+        return ret;
+    }
+
+    Consensus::LLMQType llmq_type = Params().GetConsensus().llmqTypePlatform;
+    auto quorum = m_llmq_ctx->qman->GetQuorum(llmq_type, ban_msg.m_quorum_hash);
+    if (!quorum) {
+        LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s missing quorum_hash: %s llmq_type: %d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_quorum_hash.ToString(), ToUnderlying(llmq_type));
+        ret.m_error = MisbehavingError{100};
+        return ret;
+    }
+
+    const std::string PLATFORM_BAN_REQUESTID_PREFIX = "PlatformPoSeBan";
+    const auto data = std::make_pair(ban_msg.m_protx_hash, ban_msg.m_requested_height);
+    const uint256 request_id = ::SerializeHash(std::make_pair(PLATFORM_BAN_REQUESTID_PREFIX, data));
+    const uint256 msg_hash = ::SerializeHash(data);
+
+    auto recsig_status = llmq::VerifyRecoveredSig(llmq_type, m_chainman.ActiveChainstate().m_chain, *m_llmq_ctx->qman, ban_msg.m_requested_height, request_id, msg_hash, ban_msg.m_signature);
+    if (recsig_status != llmq::VerifyRecSigStatus::Valid) {
+        LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s request_id: %s msg_hash: %s sig validation failed: %d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), request_id.ToString(), msg_hash.ToString(), ToUnderlying(recsig_status));
+        ret.m_error = MisbehavingError{100};
+        return ret;
+    }
+
+    // At this point, the outgoing message serialization version can't change.
+    const auto meta_info = m_mn_metaman.GetMetaInfo(ban_msg.m_protx_hash);
+    if (meta_info->SetPlatformBan(true, ban_msg.m_requested_height)) {
+        LogPrintf("PLATFORMBAN -- forward message to other nodes\n");
+        m_mn_metaman.RememberPlatformBan(hash, ban_msg);
+        CInv platform_ban_inv{MSG_PLATFORM_BAN, hash};
+        RelayInv(platform_ban_inv);
+    }
+    return {};
+}
+
 void PeerManagerImpl::ProcessMessage(
     CNode& pfrom,
     const std::string& msg_type,
@@ -5234,7 +5322,6 @@ void PeerManagerImpl::ProcessMessage(
         Misbehaving(pfrom.GetId(), 100, strprintf("received not-requested quorumrotationinfo. peer=%d", pfrom.GetId()));
         return;
     }
-
     if (msg_type == NetMsgType::NOTFOUND) {
         // Remove the NOTFOUND transactions from the peer
         LOCK(cs_main);
@@ -5292,6 +5379,7 @@ void PeerManagerImpl::ProcessMessage(
         PostProcessMessage(m_llmq_ctx->qman->ProcessMessage(pfrom, m_connman, msg_type, vRecv), pfrom.GetId());
         m_llmq_ctx->shareman->ProcessMessage(pfrom, *this, m_sporkman, msg_type, vRecv);
         PostProcessMessage(m_llmq_ctx->sigman->ProcessMessage(pfrom.GetId(), msg_type, vRecv), pfrom.GetId());
+        PostProcessMessage(ProcessPlatformBanMessage(pfrom.GetId(), msg_type, vRecv), pfrom.GetId());
 
         if (msg_type == NetMsgType::CLSIG) {
             if (llmq::AreChainLocksEnabled(m_sporkman)) {
diff --git a/src/node/chainstate.cpp b/src/node/chainstate.cpp
index 6ee51872820e..555cef21a831 100644
--- a/src/node/chainstate.cpp
+++ b/src/node/chainstate.cpp
@@ -219,7 +219,7 @@ void DashChainstateSetup(ChainstateManager& chainman,
 {
     // Same logic as pblocktree
     dmnman.reset();
-    dmnman = std::make_unique<CDeterministicMNManager>(*evodb);
+    dmnman = std::make_unique<CDeterministicMNManager>(*evodb, mn_metaman);
 
     cpoolman.reset();
     cpoolman = std::make_unique<CCreditPoolManager>(*evodb);
diff --git a/src/protocol.cpp b/src/protocol.cpp
index 53c1f6b8a16e..c5683a16dc9d 100644
--- a/src/protocol.cpp
+++ b/src/protocol.cpp
@@ -90,6 +90,7 @@ MAKE_MSG(SENDHEADERS2, "sendheaders2");
 MAKE_MSG(HEADERS2, "headers2");
 MAKE_MSG(GETQUORUMROTATIONINFO, "getqrinfo");
 MAKE_MSG(QUORUMROTATIONINFO, "qrinfo");
+MAKE_MSG(PLATFORMBAN, "platformban");
 }; // namespace NetMsgType
 
 /** All known message types. Keep this in the same order as the list of
@@ -170,7 +171,8 @@ const static std::string allNetMessageTypes[] = {
     NetMsgType::SENDHEADERS2,
     NetMsgType::HEADERS2,
     NetMsgType::GETQUORUMROTATIONINFO,
-    NetMsgType::QUORUMROTATIONINFO
+    NetMsgType::QUORUMROTATIONINFO,
+    NetMsgType::PLATFORMBAN,
 };
 const static std::vector<std::string> allNetMessageTypesVec(std::begin(allNetMessageTypes), std::end(allNetMessageTypes));
 
@@ -190,6 +192,7 @@ const static std::string netMessageTypesViolateBlocksOnly[] = {
     NetMsgType::DSTX,
     NetMsgType::DSVIN,
     NetMsgType::GETQUORUMROTATIONINFO,
+    NetMsgType::PLATFORMBAN,
     NetMsgType::QBSIGSHARES,
     NetMsgType::QCOMPLAINT,
     NetMsgType::QCONTRIB,
@@ -296,6 +299,7 @@ const char* CInv::GetCommandInternal() const
         case MSG_CLSIG:                         return NetMsgType::CLSIG;
         case MSG_ISDLOCK:                       return NetMsgType::ISDLOCK;
         case MSG_DSQ:                           return NetMsgType::DSQUEUE;
+        case MSG_PLATFORM_BAN:                  return NetMsgType::PLATFORMBAN;
         default:
             return nullptr;
     }
diff --git a/src/protocol.h b/src/protocol.h
index d7fc41f11598..75456d161fb7 100644
--- a/src/protocol.h
+++ b/src/protocol.h
@@ -298,6 +298,7 @@ extern const char* SENDHEADERS2;
 extern const char* HEADERS2;
 extern const char* GETQUORUMROTATIONINFO;
 extern const char* QUORUMROTATIONINFO;
+extern const char* PLATFORMBAN;
 };
 
 /* Get a vector of all valid message types (see above) */
@@ -524,6 +525,7 @@ enum GetDataMsg : uint32_t {
     /* MSG_ISLOCK = 30, */                            // Non-deterministic InstantSend and not used anymore
     MSG_ISDLOCK = 31,
     MSG_DSQ = 32,
+    MSG_PLATFORM_BAN = 33,                            // Platform service ban (DIP-0031)
 };
 
 /** inv message data */

From 73e0b3f5ae3c62acccc69d766be3b8753a1ea8b5 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Mon, 17 Mar 2025 19:15:41 +0700
Subject: [PATCH 04/23] test: add platforban message to test framework

---
 test/functional/test_framework/messages.py | 35 ++++++++++++++++++++++
 test/functional/test_framework/p2p.py      |  3 ++
 2 files changed, 38 insertions(+)

diff --git a/test/functional/test_framework/messages.py b/test/functional/test_framework/messages.py
index d55010faeed4..5bc74df2a07f 100755
--- a/test/functional/test_framework/messages.py
+++ b/test/functional/test_framework/messages.py
@@ -2379,6 +2379,41 @@ def __repr__(self):
                (self.nVersion, repr(self.inputs), self.txid, self.cycleHash)
 
 
+class msg_platformban:
+    __slots__ = ("protx_hash", "requested_height", "quorum_hash", "sig")
+    msgtype = b"platformban"
+
+    def __init__(self, protx_hash=0, requested_height=0, quorum_hash=0, sig=b'\x00' * 96):
+        self.protx_hash = protx_hash
+        self.requested_height = requested_height
+        self.quorum_hash = quorum_hash
+        self.sig = sig
+
+    def deserialize(self, f):
+        self.protx_hash = deser_uint256(f)
+        self.requested_height= struct.unpack("<I", f.read(4))[0]
+        self.quorum_hash = deser_uint256(f)
+        self.sig = f.read(96)
+
+    def serialize(self):
+        r = b""
+        r += ser_uint256(self.protx_hash)
+        r += struct.pack("<I", self.requested_height)
+        r += ser_uint256(self.quorum_hash)
+        r += self.sig
+        return r
+
+    def calc_sha256(self):
+        r = b""
+        r += ser_uint256(self.protx_hash)
+        r += struct.pack("<I", self.requested_height)
+        return uint256_from_str(hash256(r))
+
+    def __repr__(self):
+        return "msg_platformban(protx_hash=%064x requested_height=%d, quorum_hash=%064x)" % \
+               (self.protx_hash, self.requested_height, self.quorum_hash)
+
+
 class msg_qsigshare:
     __slots__ = ("sig_shares",)
     msgtype = b"qsigshare"
diff --git a/test/functional/test_framework/p2p.py b/test/functional/test_framework/p2p.py
index c5d5fbfd398e..7b384f2c2df8 100755
--- a/test/functional/test_framework/p2p.py
+++ b/test/functional/test_framework/p2p.py
@@ -65,6 +65,7 @@
     msg_merkleblock,
     msg_notfound,
     msg_ping,
+    msg_platformban,
     msg_pong,
     msg_qdata,
     msg_qgetdata,
@@ -165,6 +166,7 @@
     b"mnauth": None,
     b"mnlistdiff": msg_mnlistdiff,
     b"notfound": msg_notfound,
+    b"platformban": msg_platformban,
     b"qbsigs": None,
     b"qcomplaint": None,
     b"qcontrib": None,
@@ -616,6 +618,7 @@ def on_clsig(self, message): pass
     def on_islock(self, message): pass
     def on_isdlock(self, message): pass
 
+    def on_platformban(self, message): pass
     def on_qgetdata(self, message): pass
     def on_qdata(self, message): pass
     def on_qwatch(self, message): pass

From fbd0cf92b12d3e878cf66f467d52656e1b47a9d6 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Mon, 17 Mar 2025 18:46:51 +0700
Subject: [PATCH 05/23] test: functional test p2p_platform_ban.py

---
 test/functional/p2p_platform_ban.py | 83 +++++++++++++++++++++++++++++
 test/functional/test_runner.py      |  1 +
 2 files changed, 84 insertions(+)
 create mode 100755 test/functional/p2p_platform_ban.py

diff --git a/test/functional/p2p_platform_ban.py b/test/functional/p2p_platform_ban.py
new file mode 100755
index 000000000000..e88416ac62eb
--- /dev/null
+++ b/test/functional/p2p_platform_ban.py
@@ -0,0 +1,83 @@
+#!/usr/bin/env python3
+# Copyright (c) 2025 The Dash Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+from test_framework.messages import msg_platformban, hash256, ser_string, ser_uint256
+from test_framework.p2p import (
+    p2p_lock,
+    P2PInterface,
+)
+from test_framework.test_framework import DashTestFramework
+from test_framework.util import wait_until_helper
+
+import struct
+
+class PlatformBanInterface(P2PInterface):
+    def __init__(self):
+        super().__init__()
+
+
+class PlatformBanMessagesTest(DashTestFramework):
+    def set_test_params(self):
+        self.set_dash_test_params(1, 0, [[]], evo_count=3)
+
+    def skip_test_if_missing_module(self):
+        self.skip_if_no_wallet()
+
+    def check_banned(self, mn):
+        info = self.nodes[0].protx('info', mn.proTxHash)
+        return info['state']['PoSeBanHeight'] != -1
+
+    def run_test(self):
+        node = self.nodes[0]
+
+        node.sporkupdate("SPORK_17_QUORUM_DKG_ENABLED", 0)
+        node.sporkupdate("SPORK_23_QUORUM_POSE", 0)
+        self.wait_for_sporks_same()
+
+        evo_info_0 = self.dynamically_add_masternode(evo=True)
+        for _ in range(2):
+            self.dynamically_add_masternode(evo=True)
+
+        self.mempool_size = 0
+
+        self.mine_quorum(llmq_type_name='llmq_test_platform', llmq_type=106)
+
+        self.log.info("Create and sign platform-ban message for mn-0")
+        msg = msg_platformban()
+        msg.protx_hash = int(self.mninfo[0].proTxHash, 16)
+        msg.requested_height = node.getblockcount()
+
+        request_id_buf = ser_string(b"PlatformPoSeBan") + ser_uint256(msg.protx_hash) + struct.pack("<I", msg.requested_height)
+        request_id = hash256(request_id_buf)[::-1].hex()
+
+        quorum_hash = self.mninfo[1].get_node(self).quorum("selectquorum", 106, request_id)["quorumHash"]
+        msg.quorum_hash = int(quorum_hash, 16)
+
+        msg_hash = format(msg.calc_sha256(), '064x')
+
+        recsig = self.get_recovered_sig(request_id, msg_hash, llmq_type=106, use_platformsign=True)
+        msg.sig = bytearray.fromhex(recsig["sig"])
+
+        self.log.info("Platform ban message is created and signed")
+        p2p_node2 = self.mninfo[2].get_node(self).add_p2p_connection(PlatformBanInterface())
+        p2p_node2.send_message(msg)
+        wait_until_helper(lambda: p2p_node2.message_count["platformban"] > 0, timeout=10, lock=p2p_lock)
+        p2p_node2.message_count["platformban"] = 0
+
+
+        assert not self.check_banned(self.mninfo[0])
+
+        self.mine_quorum(llmq_type_name='llmq_test_platform', expected_members=2, expected_connections=1, expected_contributions=2, expected_commitments=2, llmq_type=106)
+
+        p2p_node = node.add_p2p_connection(PlatformBanInterface())
+        p2p_node.send_message(msg)
+        self.mine_quorum(llmq_type_name='llmq_test_platform', expected_members=2, expected_connections=1, expected_contributions=2, expected_commitments=2, llmq_type=106)
+        assert self.check_banned(self.mninfo[0])
+
+        self.dynamically_evo_update_service(evo_info_0)
+        assert not self.check_banned(self.mninfo[0])
+
+if __name__ == '__main__':
+    PlatformBanMessagesTest().main()
diff --git a/test/functional/test_runner.py b/test/functional/test_runner.py
index 89e9893a23a6..2c1a8597f535 100755
--- a/test/functional/test_runner.py
+++ b/test/functional/test_runner.py
@@ -146,6 +146,7 @@
     'rpc_verifyislock.py',
     'feature_notifications.py',
     # vv Tests less than 60s vv
+    'p2p_platform_ban.py', # NOTE: needs dash_hash to pass
     'p2p_sendheaders.py', # NOTE: needs dash_hash to pass
     'p2p_sendheaders_compressed.py', # NOTE: needs dash_hash to pass
     'wallet_importmulti.py --legacy-wallet',

From c0621a7c0e937fc0ec477821e64c1dfced015125 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Tue, 6 May 2025 20:25:55 +0700
Subject: [PATCH 06/23] fix: add missing LOCK for m_platform_ban

---
 src/masternode/meta.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/masternode/meta.cpp b/src/masternode/meta.cpp
index 8bfdcc0d9452..f029b51bb7f2 100644
--- a/src/masternode/meta.cpp
+++ b/src/masternode/meta.cpp
@@ -41,8 +41,11 @@ UniValue CMasternodeMetaInfo::ToJson() const
     ret.pushKV("lastOutboundAttemptElapsed", now - lastOutboundAttempt.load());
     ret.pushKV("lastOutboundSuccess", lastOutboundSuccess.load());
     ret.pushKV("lastOutboundSuccessElapsed", now - lastOutboundSuccess.load());
-    ret.pushKV("platform_ban", m_platform_ban);
-    ret.pushKV("platform_ban_updated", m_platform_ban_height);
+    {
+        LOCK(cs);
+        ret.pushKV("platform_ban", m_platform_ban);
+        ret.pushKV("platform_ban_updated", m_platform_ban_height);
+    }
 
     return ret;
 }

From 0cd4e4275e4215335bd87b1e48c149a8ae2f39aa Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Wed, 7 May 2025 13:59:37 +0700
Subject: [PATCH 07/23] fix: add list of valid mns for mine_quorum helper in
 p2p_platform_ban.py

---
 test/functional/p2p_platform_ban.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/functional/p2p_platform_ban.py b/test/functional/p2p_platform_ban.py
index e88416ac62eb..6c3d60a5a19e 100755
--- a/test/functional/p2p_platform_ban.py
+++ b/test/functional/p2p_platform_ban.py
@@ -69,11 +69,12 @@ def run_test(self):
 
         assert not self.check_banned(self.mninfo[0])
 
-        self.mine_quorum(llmq_type_name='llmq_test_platform', expected_members=2, expected_connections=1, expected_contributions=2, expected_commitments=2, llmq_type=106)
+        mninfos_valid = self.mninfo.copy()[1:]
+        self.mine_quorum(llmq_type_name='llmq_test_platform', expected_members=2, expected_connections=1, expected_contributions=2, expected_commitments=2, llmq_type=106, mninfos_valid=mninfos_valid)
 
         p2p_node = node.add_p2p_connection(PlatformBanInterface())
         p2p_node.send_message(msg)
-        self.mine_quorum(llmq_type_name='llmq_test_platform', expected_members=2, expected_connections=1, expected_contributions=2, expected_commitments=2, llmq_type=106)
+        self.mine_quorum(llmq_type_name='llmq_test_platform', expected_members=2, expected_connections=1, expected_contributions=2, expected_commitments=2, llmq_type=106, mninfos_valid=mninfos_valid)
         assert self.check_banned(self.mninfo[0])
 
         self.dynamically_evo_update_service(evo_info_0)

From 5affcc941ba6217ba268790028378c89974b5cb5 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Fri, 15 Aug 2025 16:28:20 +0700
Subject: [PATCH 08/23] fix: bump version in masternode meta store

---
 src/masternode/meta.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/masternode/meta.cpp b/src/masternode/meta.cpp
index f029b51bb7f2..acfd302062af 100644
--- a/src/masternode/meta.cpp
+++ b/src/masternode/meta.cpp
@@ -8,7 +8,7 @@
 #include <univalue.h>
 #include <util/time.h>
 
-const std::string MasternodeMetaStore::SERIALIZATION_VERSION_STRING = "CMasternodeMetaMan-Version-3";
+const std::string MasternodeMetaStore::SERIALIZATION_VERSION_STRING = "CMasternodeMetaMan-Version-4";
 
 CMasternodeMetaMan::CMasternodeMetaMan() :
     m_db{std::make_unique<db_type>("mncache.dat", "magicMasternodeCache")}

From 4dd0830e3105c962a0829d672fa6ec1586a8039e Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Mon, 18 Aug 2025 13:59:54 +0700
Subject: [PATCH 09/23] refactor: use std::move to make a copy of PlatformBan
 message

---
 src/masternode/meta.cpp | 4 ++--
 src/masternode/meta.h   | 2 +-
 src/net_processing.cpp  | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/masternode/meta.cpp b/src/masternode/meta.cpp
index acfd302062af..d290a30d15d7 100644
--- a/src/masternode/meta.cpp
+++ b/src/masternode/meta.cpp
@@ -145,10 +145,10 @@ std::optional<PlatformBanMessage> CMasternodeMetaMan::GetPlatformBan(const uint2
     return it->second;
 }
 
-void CMasternodeMetaMan::RememberPlatformBan(const uint256& inv_hash, PlatformBanMessage& msg)
+void CMasternodeMetaMan::RememberPlatformBan(const uint256& inv_hash, PlatformBanMessage&& msg)
 {
     LOCK(cs);
-    m_seen_platform_bans.insert({inv_hash, msg});
+    m_seen_platform_bans.insert({inv_hash, std::move(msg)});
 }
 
 std::string MasternodeMetaStore::ToString() const
diff --git a/src/masternode/meta.h b/src/masternode/meta.h
index 96fc29fcfff7..b6753170ed67 100644
--- a/src/masternode/meta.h
+++ b/src/masternode/meta.h
@@ -238,7 +238,7 @@ class CMasternodeMetaMan : public MasternodeMetaStore
 
     bool AlreadyHavePlatformBan(const uint256& inv_hash) const;
     std::optional<PlatformBanMessage> GetPlatformBan(const uint256& inv_hash) const;
-    void RememberPlatformBan(const uint256& inv_hash, PlatformBanMessage& msg);
+    void RememberPlatformBan(const uint256& inv_hash, PlatformBanMessage&& msg);
 };
 
 #endif // BITCOIN_MASTERNODE_META_H
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index ac7faa78fb6e..e7000e6f805f 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3605,7 +3605,7 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId from,
     const auto meta_info = m_mn_metaman.GetMetaInfo(ban_msg.m_protx_hash);
     if (meta_info->SetPlatformBan(true, ban_msg.m_requested_height)) {
         LogPrintf("PLATFORMBAN -- forward message to other nodes\n");
-        m_mn_metaman.RememberPlatformBan(hash, ban_msg);
+        m_mn_metaman.RememberPlatformBan(hash, std::move(ban_msg));
         CInv platform_ban_inv{MSG_PLATFORM_BAN, hash};
         RelayInv(platform_ban_inv);
     }

From 6cb94d2c00a53bd2e776e3a1051bd210b5dde99a Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Mon, 18 Aug 2025 14:34:35 +0700
Subject: [PATCH 10/23] refactor: use LRU cache instead map to limit size of
 seen platform ban messages

---
 src/masternode/meta.cpp | 12 +++++++-----
 src/masternode/meta.h   |  8 +++++++-
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/masternode/meta.cpp b/src/masternode/meta.cpp
index d290a30d15d7..9eb04dc3067f 100644
--- a/src/masternode/meta.cpp
+++ b/src/masternode/meta.cpp
@@ -133,22 +133,24 @@ std::vector<uint256> CMasternodeMetaMan::GetAndClearDirtyGovernanceObjectHashes(
 bool CMasternodeMetaMan::AlreadyHavePlatformBan(const uint256& inv_hash) const
 {
     LOCK(cs);
-    return m_seen_platform_bans.contains(inv_hash);
+    return m_seen_platform_bans.exists(inv_hash);
 }
 
 std::optional<PlatformBanMessage> CMasternodeMetaMan::GetPlatformBan(const uint256& inv_hash) const
 {
     LOCK(cs);
-    auto it = m_seen_platform_bans.find(inv_hash);
-    if (it == m_seen_platform_bans.end()) return std::nullopt;
+    PlatformBanMessage ret;
+    if (!m_seen_platform_bans.get(inv_hash, ret)) {
+        return std::nullopt;
+    }
 
-    return it->second;
+    return ret;
 }
 
 void CMasternodeMetaMan::RememberPlatformBan(const uint256& inv_hash, PlatformBanMessage&& msg)
 {
     LOCK(cs);
-    m_seen_platform_bans.insert({inv_hash, std::move(msg)});
+    m_seen_platform_bans.insert(inv_hash, std::move(msg));
 }
 
 std::string MasternodeMetaStore::ToString() const
diff --git a/src/masternode/meta.h b/src/masternode/meta.h
index b6753170ed67..9e4e68a92031 100644
--- a/src/masternode/meta.h
+++ b/src/masternode/meta.h
@@ -6,10 +6,12 @@
 #define BITCOIN_MASTERNODE_META_H
 
 #include <bls/bls.h>
+#include <saltedhasher.h>
 #include <serialize.h>
 #include <sync.h>
 #include <threadsafety.h>
 #include <uint256.h>
+#include <unordered_lru_cache.h>
 
 #include <atomic>
 #include <map>
@@ -213,7 +215,11 @@ class CMasternodeMetaMan : public MasternodeMetaStore
     bool is_valid{false};
 
     std::vector<uint256> vecDirtyGovernanceObjectHashes GUARDED_BY(cs);
-    std::map<uint256, PlatformBanMessage> m_seen_platform_bans GUARDED_BY(cs);
+
+    // equal to double of expected amount of all evo nodes, see DIP-0028
+    // it consumes no more than 1Mb of RAM but will cover extreme cases
+    static constexpr size_t SeenBanInventorySize = 900;
+    mutable unordered_lru_cache<uint256, PlatformBanMessage, StaticSaltedHasher> m_seen_platform_bans GUARDED_BY(cs) {SeenBanInventorySize};
 
 public:
     explicit CMasternodeMetaMan();

From 6d318768999ce180a22b3423a9ad7f18aa5c8c4d Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Mon, 18 Aug 2025 19:52:47 +0700
Subject: [PATCH 11/23] refactor: fixes based on code review and better
 documenting of classes

---
 src/masternode/meta.cpp |  4 ++--
 src/masternode/meta.h   | 22 +++++++++++++---------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/src/masternode/meta.cpp b/src/masternode/meta.cpp
index 9eb04dc3067f..adb2aaa30259 100644
--- a/src/masternode/meta.cpp
+++ b/src/masternode/meta.cpp
@@ -43,8 +43,8 @@ UniValue CMasternodeMetaInfo::ToJson() const
     ret.pushKV("lastOutboundSuccessElapsed", now - lastOutboundSuccess.load());
     {
         LOCK(cs);
-        ret.pushKV("platform_ban", m_platform_ban);
-        ret.pushKV("platform_ban_updated", m_platform_ban_height);
+        ret.pushKV("is_platform_banned", m_platform_ban);
+        ret.pushKV("platform_ban_height_updated", m_platform_ban_updated);
     }
 
     return ret;
diff --git a/src/masternode/meta.h b/src/masternode/meta.h
index 9e4e68a92031..4a4f0479cd43 100644
--- a/src/masternode/meta.h
+++ b/src/masternode/meta.h
@@ -50,8 +50,10 @@ class CMasternodeMetaInfo
     std::atomic<int64_t> lastOutboundAttempt{0};
     std::atomic<int64_t> lastOutboundSuccess{0};
 
+    //! bool flag is node currently under platform ban by p2p message
     bool m_platform_ban GUARDED_BY(cs){false};
-    int m_platform_ban_height GUARDED_BY(cs){0};
+    //! height at which platform ban has been applied or removed
+    int m_platform_ban_updated GUARDED_BY(cs){0};
 
 public:
     CMasternodeMetaInfo() = default;
@@ -64,7 +66,7 @@ class CMasternodeMetaInfo
         lastOutboundAttempt(ref.lastOutboundAttempt.load()),
         lastOutboundSuccess(ref.lastOutboundSuccess.load()),
         m_platform_ban(ref.m_platform_ban),
-        m_platform_ban_height(ref.m_platform_ban_height)
+        m_platform_ban_updated(ref.m_platform_ban_updated)
     {
     }
 
@@ -73,7 +75,7 @@ class CMasternodeMetaInfo
         LOCK(obj.cs);
         READWRITE(obj.proTxHash, obj.nLastDsq, obj.nMixingTxCount, obj.mapGovernanceObjectsVotedOn,
                   obj.outboundAttemptCount, obj.lastOutboundAttempt, obj.lastOutboundSuccess, obj.m_platform_ban,
-                  obj.m_platform_ban_height);
+                  obj.m_platform_ban_updated);
     }
 
     UniValue ToJson() const;
@@ -102,14 +104,14 @@ class CMasternodeMetaInfo
     bool SetPlatformBan(bool is_banned, int height)
     {
         LOCK(cs);
-        if (height < m_platform_ban_height) {
+        if (height <= m_platform_ban_updated) {
             return false;
         }
-        if (height == m_platform_ban_height && !is_banned) {
+        if (height == m_platform_ban_updated && !is_banned) {
             return false;
         }
         m_platform_ban = is_banned;
-        m_platform_ban_height = height;
+        m_platform_ban_updated = height;
         return true;
     }
     bool IsPlatformBanned() const
@@ -178,11 +180,12 @@ class MasternodeMetaStore
  * We use 2 main classes to manage Platform PoSe Ban
  *
  * PlatformBanMessage
- * PlatformBanManager - a higher-level construct which store information about ban status
+ * CMasternodeMetaInfo - a higher-level construct which store extra (non-deterministic) information about masternodes including platform ban status
  **/
 
 /**
- * PlatformBanMessage - low-level constructs which contain the m_protx_hash, m_requested_height, m_quorum_hash and m_signature
+ * PlatformBanMessage - low-level constructs which present p2p message PlatformBan containing the protx hash, requested
+ * height to ban, and BLS data: quorum hash and bls signature
  */
 class PlatformBanMessage
 {
@@ -219,7 +222,8 @@ class CMasternodeMetaMan : public MasternodeMetaStore
     // equal to double of expected amount of all evo nodes, see DIP-0028
     // it consumes no more than 1Mb of RAM but will cover extreme cases
     static constexpr size_t SeenBanInventorySize = 900;
-    mutable unordered_lru_cache<uint256, PlatformBanMessage, StaticSaltedHasher> m_seen_platform_bans GUARDED_BY(cs) {SeenBanInventorySize};
+    mutable unordered_lru_cache<uint256, PlatformBanMessage, StaticSaltedHasher> m_seen_platform_bans GUARDED_BY(cs){
+        SeenBanInventorySize};
 
 public:
     explicit CMasternodeMetaMan();

From ff705fcd6282ec85fecc99a6e6346d1a9acba4ae Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Tue, 19 Aug 2025 14:44:04 +0700
Subject: [PATCH 12/23] refactor: rename argument name from from to node

Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>
---
 src/net_processing.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index e7000e6f805f..453b598a6cb5 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3537,7 +3537,7 @@ void PeerManagerImpl::PostProcessMessage(MessageProcessingResult&& result, NodeI
     }
 }
 
-MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId from, std::string_view msg_type, CDataStream& vRecv)
+MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node, std::string_view msg_type, CDataStream& vRecv)
 {
     if (msg_type != NetMsgType::PLATFORMBAN) return {};
 
@@ -3551,7 +3551,7 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId from,
 
     const uint256 hash = ban_msg.GetHash();
 
-    LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s height: %d peer=%d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_requested_height, from);
+    LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s height: %d peer=%d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_requested_height, node);
 
     MessageProcessingResult ret{};
     const auto list = Assert(m_dmnman)->GetListAtChainTip();

From 4b4bcfd9a44329a46373ca8b557bc18eeaab95a7 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Tue, 19 Aug 2025 16:09:06 +0700
Subject: [PATCH 13/23] refactor: rename argument name from from to node II

Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>
---
 src/net_processing.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 453b598a6cb5..dff012e61b4a 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -736,7 +736,7 @@ class PeerManagerImpl final : public PeerManager
                                const std::vector<CBlockHeader>& headers,
                                bool via_compact_block)
         EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex);
-    [[nodiscard]] MessageProcessingResult ProcessPlatformBanMessage(NodeId from, std::string_view msg_type, CDataStream& vRecv)
+    [[nodiscard]] MessageProcessingResult ProcessPlatformBanMessage(NodeId node, std::string_view msg_type, CDataStream& vRecv)
         EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, g_msgproc_mutex);
 
     /** Various helpers for headers processing, invoked by ProcessHeadersMessage() */

From 33c4e363ea5944f27610d3d677077867423880f9 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Tue, 19 Aug 2025 21:19:35 +0700
Subject: [PATCH 14/23] refactor: rename day_of_blocks to
 PLATFORM_BAN_WINDOW_BLOCKS

---
 src/net_processing.cpp | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index dff012e61b4a..37f1510cef94 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3567,13 +3567,13 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node,
         ret.m_error = MisbehavingError{100};
         return ret;
     }
-    constexpr int day_of_blocks = 576;
+    static constexpr int PLATFORM_BAN_WINDOW_BLOCKS = 576;
     int tipHeight = WITH_LOCK(cs_main, return m_chainman.ActiveChainstate().m_chain.Height());
-    if (tipHeight < ban_msg.m_requested_height || tipHeight - day_of_blocks > ban_msg.m_requested_height) {
-        // m_requested_height is inside the range [TipHeight - 576 - 5, TipHeight + 5]
+    if (tipHeight < ban_msg.m_requested_height || tipHeight - PLATFORM_BAN_WINDOW_BLOCKS > ban_msg.m_requested_height) {
+        // m_requested_height is inside the range [TipHeight - PLATFORM_BAN_WINDOW_BLOCKS - 5, TipHeight + 5]
         LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s unexpected height: %d tip: %d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_requested_height, tipHeight);
-        if (tipHeight + 5 < ban_msg.m_requested_height || tipHeight - day_of_blocks - 5 > ban_msg.m_requested_height) {
-            // m_requested_height is outside the range [TipHeight - 576 - 5, TipHeight + 5]
+        if (tipHeight + 5 < ban_msg.m_requested_height || tipHeight - PLATFORM_BAN_WINDOW_BLOCKS - 5 > ban_msg.m_requested_height) {
+            // m_requested_height is outside the range [TipHeight - PLATFORM_BAN_WINDOW_BLOCKS - 5, TipHeight + 5]
             ret.m_error = MisbehavingError{10};
             return ret;
         }

From 0860a12c20e1aa5bdf39349ecc9234022327746e Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Tue, 19 Aug 2025 21:36:03 +0700
Subject: [PATCH 15/23] fix: add missing call of EraseObjectRequest for
 platform ban p2p message

---
 src/net_processing.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 37f1510cef94..823152eb3d7b 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3553,6 +3553,8 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node,
 
     LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s height: %d peer=%d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_requested_height, node);
 
+    WITH_LOCK(::cs_main, EraseObjectRequest(node, CInv{MSG_PLATFORM_BAN, hash}));
+
     MessageProcessingResult ret{};
     const auto list = Assert(m_dmnman)->GetListAtChainTip();
     auto dmn = list.GetMN(ban_msg.m_protx_hash);

From d221a65861cf1f3f0a9cee90cd1be599092734ee Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Wed, 20 Aug 2025 00:28:57 +0700
Subject: [PATCH 16/23] refactor: let PostProcessMessage do the job

It replaces direct call of EraseObjectRequest

Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>
---
 src/net_processing.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 823152eb3d7b..16bb6fcb8b92 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3553,9 +3553,9 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node,
 
     LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s height: %d peer=%d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), ban_msg.m_requested_height, node);
 
-    WITH_LOCK(::cs_main, EraseObjectRequest(node, CInv{MSG_PLATFORM_BAN, hash}));
-
     MessageProcessingResult ret{};
+    ret.m_to_erase = CInv{MSG_PLATFORM_BAN, hash};
+
     const auto list = Assert(m_dmnman)->GetListAtChainTip();
     auto dmn = list.GetMN(ban_msg.m_protx_hash);
     if (!dmn) {

From 42f9d7cd04d77b7d84460172e08de3c0d9155fd8 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Wed, 20 Aug 2025 01:02:09 +0700
Subject: [PATCH 17/23] refactor: let PostProcessMessage do the job II

Now for RelayInv too

Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>
---
 src/net_processing.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 16bb6fcb8b92..cb575c9844c5 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3608,8 +3608,7 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node,
     if (meta_info->SetPlatformBan(true, ban_msg.m_requested_height)) {
         LogPrintf("PLATFORMBAN -- forward message to other nodes\n");
         m_mn_metaman.RememberPlatformBan(hash, std::move(ban_msg));
-        CInv platform_ban_inv{MSG_PLATFORM_BAN, hash};
-        RelayInv(platform_ban_inv);
+        ret.m_inventory = CInv{MSG_PLATFORM_BAN, hash};
     }
     return {};
 }

From 2af28449ed07a741c4d78dacdb91fe4851a76668 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Wed, 20 Aug 2025 00:43:31 +0700
Subject: [PATCH 18/23] fix: return ret instead {}, missing usage

---
 src/net_processing.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index cb575c9844c5..5a850063d38f 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3610,7 +3610,7 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node,
         m_mn_metaman.RememberPlatformBan(hash, std::move(ban_msg));
         ret.m_inventory = CInv{MSG_PLATFORM_BAN, hash};
     }
-    return {};
+    return ret;
 }
 
 void PeerManagerImpl::ProcessMessage(

From 8ec5e20267998199ca4f78a7492e07e985e513f5 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Wed, 20 Aug 2025 01:27:23 +0700
Subject: [PATCH 19/23] fix: misusing m_inventory for ProcessMessageRet

---
 src/net_processing.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 5a850063d38f..83c2ed6771a4 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3608,7 +3608,7 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node,
     if (meta_info->SetPlatformBan(true, ban_msg.m_requested_height)) {
         LogPrintf("PLATFORMBAN -- forward message to other nodes\n");
         m_mn_metaman.RememberPlatformBan(hash, std::move(ban_msg));
-        ret.m_inventory = CInv{MSG_PLATFORM_BAN, hash};
+        ret.m_inventory.emplace_back(MSG_PLATFORM_BAN, hash);
     }
     return ret;
 }

From 0e0e1ce0aba96bb08425f8f7b219e0e38e55c680 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Wed, 20 Aug 2025 01:24:23 +0700
Subject: [PATCH 20/23] fix: enforce quorum hash while validation platform ban
 p2p message

---
 src/net_processing.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 83c2ed6771a4..f98ba7bfdeb8 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3596,9 +3596,10 @@ MessageProcessingResult PeerManagerImpl::ProcessPlatformBanMessage(NodeId node,
     const uint256 request_id = ::SerializeHash(std::make_pair(PLATFORM_BAN_REQUESTID_PREFIX, data));
     const uint256 msg_hash = ::SerializeHash(data);
 
-    auto recsig_status = llmq::VerifyRecoveredSig(llmq_type, m_chainman.ActiveChainstate().m_chain, *m_llmq_ctx->qman, ban_msg.m_requested_height, request_id, msg_hash, ban_msg.m_signature);
-    if (recsig_status != llmq::VerifyRecSigStatus::Valid) {
-        LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s request_id: %s msg_hash: %s sig validation failed: %d\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), request_id.ToString(), msg_hash.ToString(), ToUnderlying(recsig_status));
+    uint256 signHash = llmq::BuildSignHash(llmq_type, quorum->qc->quorumHash, request_id, msg_hash);
+
+    if (!ban_msg.m_signature.VerifyInsecure(quorum->qc->quorumPublicKey, signHash)) {
+        LogPrintf("PLATFORMBAN -- hash: %s protx_hash: %s request_id: %s msg_hash: %s sig validation failed\n", hash.ToString(), ban_msg.m_protx_hash.ToString(), request_id.ToString(), msg_hash.ToString());
         ret.m_error = MisbehavingError{100};
         return ret;
     }

From efc3a3d3db0b8fc171f9af91524afc9676b4057f Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Fri, 22 Aug 2025 15:16:14 +0700
Subject: [PATCH 21/23] fix: no flipping ban/unban if it's the same height for
 p2p message for node revive

---
 src/masternode/meta.h | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/src/masternode/meta.h b/src/masternode/meta.h
index 4a4f0479cd43..3fa5c27074a5 100644
--- a/src/masternode/meta.h
+++ b/src/masternode/meta.h
@@ -104,10 +104,7 @@ class CMasternodeMetaInfo
     bool SetPlatformBan(bool is_banned, int height)
     {
         LOCK(cs);
-        if (height <= m_platform_ban_updated) {
-            return false;
-        }
-        if (height == m_platform_ban_updated && !is_banned) {
+        if (height < m_platform_ban_updated) {
             return false;
         }
         m_platform_ban = is_banned;

From af6f2cc3e05b7d89f2aca9c302eb1a34f176cce2 Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Fri, 29 Aug 2025 02:33:20 +0700
Subject: [PATCH 22/23] fixup: prevent flipping "is banned" for the equal
 height

Consensus leans to ban it
---
 src/masternode/meta.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/masternode/meta.h b/src/masternode/meta.h
index 3fa5c27074a5..e06a10cceed9 100644
--- a/src/masternode/meta.h
+++ b/src/masternode/meta.h
@@ -107,6 +107,9 @@ class CMasternodeMetaInfo
         if (height < m_platform_ban_updated) {
             return false;
         }
+        if (height == m_platform_ban_updated && !is_banned) {
+            return false;
+        }
         m_platform_ban = is_banned;
         m_platform_ban_updated = height;
         return true;

From 64d2f67d4b6c2fb78efc1f4f530d936df55e867c Mon Sep 17 00:00:00 2001
From: Konstantin Akimov <knstqq@gmail.com>
Date: Mon, 1 Sep 2025 20:39:27 +0700
Subject: [PATCH 23/23] fmt: removed dub newline in p2p_platform_ban.py

Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>
---
 test/functional/p2p_platform_ban.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/functional/p2p_platform_ban.py b/test/functional/p2p_platform_ban.py
index 6c3d60a5a19e..cb9cb362dbf1 100755
--- a/test/functional/p2p_platform_ban.py
+++ b/test/functional/p2p_platform_ban.py
@@ -66,7 +66,6 @@ def run_test(self):
         wait_until_helper(lambda: p2p_node2.message_count["platformban"] > 0, timeout=10, lock=p2p_lock)
         p2p_node2.message_count["platformban"] = 0
 
-
         assert not self.check_banned(self.mninfo[0])
 
         mninfos_valid = self.mninfo.copy()[1:]
@@ -80,5 +79,6 @@ def run_test(self):
         self.dynamically_evo_update_service(evo_info_0)
         assert not self.check_banned(self.mninfo[0])
 
+
 if __name__ == '__main__':
     PlatformBanMessagesTest().main()