From b079fb63c759a27ef090ad759a102d1b108f5650 Mon Sep 17 00:00:00 2001
From: yggverse <yggverse@project>
Date: Sat, 4 Oct 2025 06:44:34 +0300
Subject: [PATCH] implement initial mycelium network condition

---
 libi2pd/util.cpp | 11 +++++++++++
 libi2pd/util.h   |  1 +
 2 files changed, 12 insertions(+)

diff --git a/libi2pd/util.cpp b/libi2pd/util.cpp
index 94f3cd43..1840c5dd 100644
--- a/libi2pd/util.cpp
+++ b/libi2pd/util.cpp
@@ -636,6 +636,17 @@ namespace net
 		return IsYggdrasilAddress (addr.to_v6 ().to_bytes ().data ());
 	}
 
+	static bool IsMyceliumAddress (const uint8_t addr[16])
+	{
+		return addr[0] == 0x04 || addr[0] == 0x05;
+	}
+
+	bool IsMyceliumAddress (const boost::asio::ip::address& addr)
+	{
+		if (!addr.is_v6 ()) return false;
+		return IsMyceliumAddress (addr.to_v6 ().to_bytes ().data ());
+	}
+
 	bool IsPortInReservedRange (const uint16_t port) noexcept
 	{
 		// https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers (Feb. 3, 2023) + Tor browser (9150)
diff --git a/libi2pd/util.h b/libi2pd/util.h
index 59901f2b..b3705381 100644
--- a/libi2pd/util.h
+++ b/libi2pd/util.h
@@ -275,6 +275,7 @@ namespace util
 		bool IsLocalAddress (const boost::asio::ip::address& addr);
 		bool IsInReservedRange (const boost::asio::ip::address& host);
 		bool IsYggdrasilAddress (const boost::asio::ip::address& addr);
+		bool IsMyceliumAddress (const boost::asio::ip::address& addr);
 		bool IsPortInReservedRange (const uint16_t port) noexcept;
 	}
 }