Merge #19725: [RPC] Add connection type to getpeerinfo, improve logs

a512925e19a70d7f6b80ac530a169f45ffaafa1c [doc] Release notes (Amiti Uttarwar)
50f94b34a33c954f6e207f509c93d33267a5c3e2 [rpc] Deprecate getpeerinfo addnode field (Amiti Uttarwar)
df091b9b509f0b10e4315c0bfa2da0cc0c31c22f [refactor] Rename test file to allow any getpeerinfo deprecations. (Amiti Uttarwar)
395acfa83a5436790c1a722a5609ac9d48df235f [rpc] Add connection type to getpeerinfo RPC, update tests (Amiti Uttarwar)
49c10a9ca40967d28ae16dfea9cccc6f3a6624a1 [log] Add connection type to log statement (Amiti Uttarwar)

Pull request description:

  After #19316, we can more directly expose information about the connection type on the `getpeerinfo` RPC. Doing so also makes the existing addnode field redundant, so this PR begins the process of deprecating this field.

  This PR also includes one commit that improves a log message, as both use a shared function to return the connection type as a string.

  Suggested by sdaftuar- https://github.com/bitcoin/bitcoin/pull/19316#discussion_r468001604 & https://github.com/bitcoin/bitcoin/pull/19316#discussion_r468018093

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Tree-SHA512: 601a7a38aee235ee59aca690784f886dc2ae4e418b2e6422c4b58cd597376c00f74910f66920b08a08a0bec28bf8022e71a1435785ff6ba8a188954261aba78e

4 files changed, 42 insertions, 7 deletions

diff --git a/src/net.cpp b/src/net.cpp
index e7d3a146f..5b533d7d1 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -488,6 +488,26 @@ void CConnman::AddWhitelistPermissionFlags(NetPermissionFlags& flags, const CNet
     }
 }
 
+std::string CNode::ConnectionTypeAsString() const
+{
+    switch (m_conn_type) {
+    case ConnectionType::INBOUND:
+        return "inbound";
+    case ConnectionType::MANUAL:
+        return "manual";
+    case ConnectionType::FEELER:
+        return "feeler";
+    case ConnectionType::OUTBOUND_FULL_RELAY:
+        return "outbound-full-relay";
+    case ConnectionType::BLOCK_RELAY:
+        return "block-relay-only";
+    case ConnectionType::ADDR_FETCH:
+        return "addr-fetch";
+    } // no default case, so the compiler can warn about missing cases
+
+    assert(false);
+}
+
 std::string CNode::GetAddrName() const {
     LOCK(cs_addrName);
     return addrName;
@@ -582,6 +602,8 @@ void CNode::copyStats(CNodeStats &stats, const std::vector<bool> &m_asmap)
     // Leave string empty if addrLocal invalid (not filled in yet)
     CService addrLocalUnlocked = GetAddrLocal();
     stats.addrLocal = addrLocalUnlocked.IsValid() ? addrLocalUnlocked.ToString() : "";
+
+    stats.m_conn_type_string = ConnectionTypeAsString();
 }
 #undef X
 
diff --git a/src/net.h b/src/net.h
index 62167014f..5a8e57b68 100644
--- a/src/net.h
+++ b/src/net.h
@@ -114,6 +114,14 @@ struct CSerializedNetMsg
     std::string m_type;
 };
 
+const std::vector<std::string> CONNECTION_TYPE_DOC{
+    "outbound-full-relay (default automatic connections)",
+    "block-relay-only (does not relay transactions or addresses)",
+    "inbound (initiated by the peer)",
+    "manual (added via addnode RPC or -addnode/-connect configuration options)",
+    "addr-fetch (short-lived automatic connection for soliciting addresses)",
+    "feeler (short-lived automatic connection for testing addresses)"};
+
 /** Different types of connections to a peer. This enum encapsulates the
  * information we have available at the time of opening or accepting the
  * connection. Aside from INBOUND, all types are initiated by us. */
@@ -691,6 +699,7 @@ public:
     // Bind address of our side of the connection
     CAddress addrBind;
     uint32_t m_mapped_as;
+    std::string m_conn_type_string;
 };
 
 
@@ -1144,6 +1153,8 @@ public:
     std::string GetAddrName() const;
     //! Sets the addrName only if it was not previously set
     void MaybeSetAddrName(const std::string& addrNameIn);
+
+    std::string ConnectionTypeAsString() const;
 };
 
 /** Return a timestamp in the future (in microseconds) for exponentially distributed events. */
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index f3f30285d..d2a76550e 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -3520,11 +3520,7 @@ void PeerManager::ProcessMessage(CNode& pfrom, const std::string& msg_type, CDat
         // Making nodes which are behind NAT and can only make outgoing connections ignore
         // the getaddr message mitigates the attack.
         if (!pfrom.IsInboundConn()) {
-            LogPrint(BCLog::NET, "Ignoring \"getaddr\" from outbound connection. peer=%d\n", pfrom.GetId());
-            return;
-        }
-        if (!pfrom.RelayAddrsWithConn()) {
-            LogPrint(BCLog::NET, "Ignoring \"getaddr\" from block-relay-only connection. peer=%d\n", pfrom.GetId());
+            LogPrint(BCLog::NET, "Ignoring \"getaddr\" from %s connection. peer=%d\n", pfrom.ConnectionTypeAsString(), pfrom.GetId());
             return;
         }
 
diff --git a/src/rpc/net.cpp b/src/rpc/net.cpp
index 11a2d23d8..def21b119 100644
--- a/src/rpc/net.cpp
+++ b/src/rpc/net.cpp
@@ -116,7 +116,9 @@ static RPCHelpMan getpeerinfo()
                             {RPCResult::Type::NUM, "version", "The peer version, such as 70001"},
                             {RPCResult::Type::STR, "subver", "The string version"},
                             {RPCResult::Type::BOOL, "inbound", "Inbound (true) or Outbound (false)"},
-                            {RPCResult::Type::BOOL, "addnode", "Whether connection was due to addnode/-connect or if it was an automatic/inbound connection"},
+                            {RPCResult::Type::BOOL, "addnode", "Whether connection was due to addnode/-connect or if it was an automatic/inbound connection\n"
+                                                               "(DEPRECATED, returned only if the config option -deprecatedrpc=getpeerinfo_addnode is passed)"},
+                            {RPCResult::Type::STR, "connection_type", "Type of connection: \n" + Join(CONNECTION_TYPE_DOC, ",\n") + "."},
                             {RPCResult::Type::NUM, "startingheight", "The starting height (block) of the peer"},
                             {RPCResult::Type::NUM, "banscore", "The ban score (DEPRECATED, returned only if config option -deprecatedrpc=banscore is passed)"},
                             {RPCResult::Type::NUM, "synced_headers", "The last header we have in common with this peer"},
@@ -196,7 +198,10 @@ static RPCHelpMan getpeerinfo()
         // their ver message.
         obj.pushKV("subver", stats.cleanSubVer);
         obj.pushKV("inbound", stats.fInbound);
-        obj.pushKV("addnode", stats.m_manual_connection);
+        if (IsDeprecatedRPCEnabled("getpeerinfo_addnode")) {
+            // addnode is deprecated in v0.21 for removal in v0.22
+            obj.pushKV("addnode", stats.m_manual_connection);
+        }
         obj.pushKV("startingheight", stats.nStartingHeight);
         if (fStateStats) {
             if (IsDeprecatedRPCEnabled("banscore")) {
@@ -232,6 +237,7 @@ static RPCHelpMan getpeerinfo()
                 recvPerMsgCmd.pushKV(i.first, i.second);
         }
         obj.pushKV("bytesrecv_per_msg", recvPerMsgCmd);
+        obj.pushKV("connection_type", stats.m_conn_type_string);
 
         ret.push_back(obj);
     }