Merge #19474: doc: Use precise permission flags where possible

fab558612278909df93bdf88f5727b04f13aef0f doc: Use precise permission flags where possible (MarcoFalke)

Pull request description:

  Instead of mentioning the all-encompassing `-whitelist*` settings, change the docs to mention the exact permission flag that will influence the behaviour.

  This is needed because in the future, the too-broad `-whitelist*` settings (they either include *all* permission flags or apply to *all* peers) might be deprecated to require the permission flags to be enumerated.

  Alternatively, in the future there could be an RPC to set the net permission flags on an existing connection, in which case the `-whitelist*` terminology is of no help.

ACKs for top commit:
  jnewbery:
    reACK fab558612278909df93bdf88f5727b04f13aef0f
  fjahr:
    Code review ACK fab558612278909df93bdf88f5727b04f13aef0f
  jonatack:
    ACK fab558612278909df93bdf88f5727b04f13aef0f

Tree-SHA512: c7dea3e577d90103bb2b0ffab7b7c8640b388932a3a880f69e2b70747fc9213dc1f437085671fd54c902ec2a578458b8a2fae6dbe076642fb88efbf9fa9e679c

1 files changed, 15 insertions, 14 deletions

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 8ef79cd719..bfc60b18f9 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -117,7 +117,7 @@ static constexpr std::chrono::hours AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL{24};
 /** Average delay between peer address broadcasts */
 static constexpr std::chrono::seconds AVG_ADDRESS_BROADCAST_INTERVAL{30};
 /** Average delay between trickled inventory transmissions in seconds.
- *  Blocks and whitelisted receivers bypass this, outbound peers get half this delay. */
+ *  Blocks and peers with noban permission bypass this, outbound peers get half this delay. */
 static const unsigned int INVENTORY_BROADCAST_INTERVAL = 5;
 /** Maximum number of inventory items to send per transmission.
  *  Limits the impact of low-fee transaction floods. */
@@ -249,7 +249,7 @@ struct CNodeState {
     bool fCurrentlyConnected;
     //! Accumulated misbehaviour score for this peer.
     int nMisbehavior;
-    //! Whether this peer should be disconnected and marked as discouraged (unless whitelisted with noban).
+    //! Whether this peer should be disconnected and marked as discouraged (unless it has the noban permission).
     bool m_should_discourage;
     //! String name of this peer (debugging/logging purposes).
     const std::string name;
@@ -1895,8 +1895,8 @@ static void ProcessHeadersMessage(CNode& pfrom, CConnman* connman, ChainstateMan
             // headers to fetch from this peer.
             if (nodestate->pindexBestKnownBlock && nodestate->pindexBestKnownBlock->nChainWork < nMinimumChainWork) {
                 // This peer has too little work on their headers chain to help
-                // us sync -- disconnect if using an outbound slot (unless
-                // whitelisted or addnode).
+                // us sync -- disconnect if it is an outbound disconnection
+                // candidate.
                 // Note: We compare their tip to nMinimumChainWork (rather than
                 // ::ChainActive().Tip()) because we won't start block download
                 // until we have a headers chain that has at least
@@ -2531,9 +2531,10 @@ void ProcessMessage(
         // block-relay-only peer
         bool fBlocksOnly = !g_relay_txes || (pfrom.m_tx_relay == nullptr);
 
-        // Allow whitelisted peers to send data other than blocks in blocks only mode if whitelistrelay is true
-        if (pfrom.HasPermission(PF_RELAY))
+        // Allow peers with relay permission to send data other than blocks in blocks only mode
+        if (pfrom.HasPermission(PF_RELAY)) {
             fBlocksOnly = false;
+        }
 
         LOCK(cs_main);
 
@@ -2887,14 +2888,14 @@ void ProcessMessage(
             }
 
             if (pfrom.HasPermission(PF_FORCERELAY)) {
-                // Always relay transactions received from whitelisted peers, even
+                // Always relay transactions received from peers with forcerelay permission, even
                 // if they were already in the mempool,
                 // allowing the node to function as a gateway for
                 // nodes hidden behind it.
                 if (!mempool.exists(tx.GetHash())) {
-                    LogPrintf("Not relaying non-mempool transaction %s from whitelisted peer=%d\n", tx.GetHash().ToString(), pfrom.GetId());
+                    LogPrintf("Not relaying non-mempool transaction %s from forcerelay peer=%d\n", tx.GetHash().ToString(), pfrom.GetId());
                 } else {
-                    LogPrintf("Force relaying tx %s from whitelisted peer=%d\n", tx.GetHash().ToString(), pfrom.GetId());
+                    LogPrintf("Force relaying tx %s from peer=%d\n", tx.GetHash().ToString(), pfrom.GetId());
                     RelayTransaction(tx.GetHash(), *connman);
                 }
             }
@@ -3044,7 +3045,7 @@ void ProcessMessage(
                 PartiallyDownloadedBlock& partialBlock = *(*queuedBlockIt)->partialBlock;
                 ReadStatus status = partialBlock.InitData(cmpctblock, vExtraTxnForCompact);
                 if (status == READ_STATUS_INVALID) {
-                    MarkBlockAsReceived(pindex->GetBlockHash()); // Reset in-flight state in case of whitelist
+                    MarkBlockAsReceived(pindex->GetBlockHash()); // Reset in-flight state in case Misbehaving does not result in a disconnect
                     Misbehaving(pfrom.GetId(), 100, strprintf("Peer %d sent us invalid compact block\n", pfrom.GetId()));
                     return;
                 } else if (status == READ_STATUS_FAILED) {
@@ -3177,7 +3178,7 @@ void ProcessMessage(
             PartiallyDownloadedBlock& partialBlock = *it->second.second->partialBlock;
             ReadStatus status = partialBlock.FillBlock(*pblock, resp.txn);
             if (status == READ_STATUS_INVALID) {
-                MarkBlockAsReceived(resp.blockhash); // Reset in-flight state in case of whitelist
+                MarkBlockAsReceived(resp.blockhash); // Reset in-flight state in case Misbehaving does not result in a disconnect
                 Misbehaving(pfrom.GetId(), 100, strprintf("Peer %d sent us invalid compact block/non-matching block transactions\n", pfrom.GetId()));
                 return;
             } else if (status == READ_STATUS_FAILED) {
@@ -4258,9 +4259,9 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
         // Check for headers sync timeouts
         if (state.fSyncStarted && state.nHeadersSyncTimeout < std::numeric_limits<int64_t>::max()) {
             // Detect whether this is a stalling initial-headers-sync peer
-            if (pindexBestHeader->GetBlockTime() <= GetAdjustedTime() - 24*60*60) {
+            if (pindexBestHeader->GetBlockTime() <= GetAdjustedTime() - 24 * 60 * 60) {
                 if (nNow > state.nHeadersSyncTimeout && nSyncStarted == 1 && (nPreferredDownload - state.fPreferredDownload >= 1)) {
-                    // Disconnect a (non-whitelisted) peer if it is our only sync peer,
+                    // Disconnect a peer (without the noban permission) if it is our only sync peer,
                     // and we have others we could be using instead.
                     // Note: If all our peers are inbound, then we won't
                     // disconnect our sync peer for stalling; we have bigger
@@ -4270,7 +4271,7 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
                         pto->fDisconnect = true;
                         return true;
                     } else {
-                        LogPrintf("Timeout downloading headers from whitelisted peer=%d, not disconnecting\n", pto->GetId());
+                        LogPrintf("Timeout downloading headers from noban peer=%d, not disconnecting\n", pto->GetId());
                         // Reset the headers sync state so that we have a
                         // chance to try downloading from a different peer.
                         // Note: this will also result in at least one more