From 8bc8c1abe876e2bbebe39f1c2744250033894d0d Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@libtorrent.org>
Date: Mon, 25 Mar 2013 07:26:39 +0000
Subject: [PATCH] merged implied_port from RC_0_16

---
 ChangeLog                           |  1 +
 include/libtorrent/kademlia/msg.hpp | 49 -----------------------------
 src/kademlia/node.cpp               | 11 +++++--
 3 files changed, 10 insertions(+), 51 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a50537d81..cfbab8b94 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -19,6 +19,7 @@
 	* fix uTP edge case where udp socket buffer fills up
 	* fix nagle implementation in uTP
 
+	* support 'implied_port' in DHT announce_peer
 	* don't use pool allocator for disk blocks (cache may now return pages to the kernel)
 
 0.16.9 release
diff --git a/include/libtorrent/kademlia/msg.hpp b/include/libtorrent/kademlia/msg.hpp
index 5b160ef88..80e88a585 100644
--- a/include/libtorrent/kademlia/msg.hpp
+++ b/include/libtorrent/kademlia/msg.hpp
@@ -46,55 +46,6 @@ namespace libtorrent {
 namespace dht {
 
 typedef std::vector<char> packet_t;
-/*
-namespace messages
-{
-	enum { ping = 0, find_node = 1, get_peers = 2, announce_peer = 3, error = 4 };
-	char const* const ids[] = { "ping", "find_node", "get_peers", "announce_peer", "error" }; 
-} // namespace messages
-
-struct msg
-{
-	msg()
-		: reply(false)
-		, message_id(-1)
-		, port(0)
-	{}
-
-	// true if this message is a reply
-	bool reply;
-	// the kind if message
-	int message_id;
-	// if this is a reply, a copy of the transaction id
-	// from the request. If it's a request, a transaction
-	// id that should be sent back in the reply
-	std::string transaction_id;
-	// the node id of the process sending the message
-	node_id id;
-	// the address of the process sending or receiving
-	// the message.
-	udp::endpoint addr;
-	// if this is a nodes response, these are the nodes
-	nodes_t nodes;
-
-	peers_t peers;
-	
-	// similar to transaction_id but for write operations.
-	std::string write_token;
-
-	// the info has for peer_requests, announce_peer
-	// and responses
-	node_id info_hash;
-	
-	// port for announce_peer messages
-	int port;
-	
-	// ERROR MESSAGES
-	int error_code;
-	std::string error_msg;
-};
-*/
-
 typedef std::vector<node_entry> nodes_t;
 typedef std::vector<tcp::endpoint> peers_t;
 
diff --git a/src/kademlia/node.cpp b/src/kademlia/node.cpp
index 0418aa163..6b5ea70d2 100644
--- a/src/kademlia/node.cpp
+++ b/src/kademlia/node.cpp
@@ -703,10 +703,11 @@ void node_impl::incoming_request(msg const& m, entry& e)
 			{"token", lazy_entry::string_t, 0, 0},
 			{"n", lazy_entry::string_t, 0, key_desc_t::optional},
 			{"seed", lazy_entry::int_t, 0, key_desc_t::optional},
+			{"implied_port", lazy_entry::int_t, 0, key_desc_t::optional},
 		};
 
-		lazy_entry const* msg_keys[5];
-		if (!verify_message(arg_ent, msg_desc, msg_keys, 5, error_string, sizeof(error_string)))
+		lazy_entry const* msg_keys[6];
+		if (!verify_message(arg_ent, msg_desc, msg_keys, 6, error_string, sizeof(error_string)))
 		{
 #ifdef TORRENT_DHT_VERBOSE_LOGGING
 			++g_failed_announces;
@@ -716,6 +717,12 @@ void node_impl::incoming_request(msg const& m, entry& e)
 		}
 
 		int port = int(msg_keys[1]->int_value());
+
+		// is the announcer asking to ignore the explicit
+		// listen port and instead use the source port of the packet?
+		if (msg_keys[5] && msg_keys[5]->int_value() != 0)
+			port = m.addr.port();
+
 		if (port < 0 || port >= 65536)
 		{
 #ifdef TORRENT_DHT_VERBOSE_LOGGING