Add CNetAddr::IsPrivacyNet() and CNode::IsConnectedThroughPrivacyNet()

Co-authored-by: Vasil Dimov <vd@FreeBSD.org>

src/net.cpp

@@ -620,6 +620,11 @@ Network CNode::ConnectedThroughNetwork() const
     return m_inbound_onion ? NET_ONION : addr.GetNetClass();
 }
 
+bool CNode::IsConnectedThroughPrivacyNet() const
+{
+    return m_inbound_onion || addr.IsPrivacyNet();
+}
+
 #undef X
 #define X(name) stats.name = name
 void CNode::CopyStats(CNodeStats& stats)

src/net.h

@@ -506,6 +506,9 @@ public:
      */
     Network ConnectedThroughNetwork() const;
 
+    /** Whether this peer connected through a privacy network. */
+    [[nodiscard]] bool IsConnectedThroughPrivacyNet() const;
+
     // We selected peer as (compact blocks) high-bandwidth peer (BIP152)
     std::atomic<bool> m_bip152_highbandwidth_to{false};
     // Peer selected us as (compact blocks) high-bandwidth peer (BIP152)

src/netaddress.h

@@ -188,6 +188,13 @@ public:
     bool IsInternal() const;
     bool IsValid() const;
 
+    /**
+     * Whether this object is a privacy network.
+     * TODO: consider adding IsCJDNS() here when more peers adopt CJDNS, see:
+     * https://github.com/bitcoin/bitcoin/pull/27411#issuecomment-1497176155
+     */
+    [[nodiscard]] bool IsPrivacyNet() const { return IsTor() || IsI2P(); }
+
     /**
      * Check if the current object can be serialized in pre-ADDRv2/BIP155 format.
      */