From 07282ec39f5457b4fc8eb338f1c8bcec5692a627 Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Sun, 24 Jan 2021 19:42:44 -0500
Subject: [PATCH] get local yggdrasil ipv6 address

---
 libi2pd/util.cpp | 30 ++++++++++++++++++++++++++++++
 libi2pd/util.h   |  1 +
 2 files changed, 31 insertions(+)

diff --git a/libi2pd/util.cpp b/libi2pd/util.cpp
index 794a3f14..bb3f60d1 100644
--- a/libi2pd/util.cpp
+++ b/libi2pd/util.cpp
@@ -416,6 +416,36 @@ namespace net
 #endif
 	}
 
+	boost::asio::ip::address_v6 GetYggdrasilAddress ()
+	{
+#ifdef _WIN32
+		// TODO: implement
+		return boost::asio::ip::address_v6 ();
+#else
+		ifaddrs * addrs = nullptr;
+		auto err = getifaddrs(&addrs);
+		if (!err)
+		{
+			ifaddrs * cur = addrs;
+			while(cur)
+			{
+				if (cur->ifa_addr && cur->ifa_addr->sa_family == AF_INET6)
+				{
+					sockaddr_in6* sa = (sockaddr_in6*)cur->ifa_addr;
+					if (sa->sin6_addr.s6_addr[0] == 0x02 || sa->sin6_addr.s6_addr[0] == 0x03)
+					{
+						boost::asio::ip::address_v6::bytes_type bytes;
+						memcpy (bytes.data (), &sa->sin6_addr, 16);
+						return boost::asio::ip::address_v6 (bytes);
+					}	
+				}	
+				cur = cur->ifa_next;
+			}	
+		}
+		return boost::asio::ip::address_v6 ();
+#endif		
+	}	
+	
 	bool IsInReservedRange (const boost::asio::ip::address& host) {
 		// https://en.wikipedia.org/wiki/Reserved_IP_addresses
 		if(host.is_v4())
diff --git a/libi2pd/util.h b/libi2pd/util.h
index e6de09ed..7a45dc9b 100644
--- a/libi2pd/util.h
+++ b/libi2pd/util.h
@@ -188,6 +188,7 @@ namespace util
 	{
 		int GetMTU (const boost::asio::ip::address& localAddress);
 		const boost::asio::ip::address GetInterfaceAddress (const std::string & ifname, bool ipv6=false);
+		boost::asio::ip::address_v6 GetYggdrasilAddress ();
 		bool IsInReservedRange (const boost::asio::ip::address& host);
 	}
 }