From e6e051e7c5642ed46131978d9a98ab44fe898914 Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@libtorrent.org>
Date: Sun, 6 Jan 2008 07:35:32 +0000
Subject: [PATCH] improves logic to handle slightly broken .torrent files and
 added tests

---
 src/torrent_info.cpp     | 19 +++++++++++++++----
 test/test_primitives.cpp | 14 +++++++++++++-
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/src/torrent_info.cpp b/src/torrent_info.cpp
index be06b77a0..d3c72ca70 100755
--- a/src/torrent_info.cpp
+++ b/src/torrent_info.cpp
@@ -386,12 +386,23 @@ namespace libtorrent
 		fs::path tmp = m_name;
 		if (tmp.is_complete())
 		{
-			error = "torrent contains a file with an absolute path: '" + m_name + "'";
-			return false;
+			m_name = tmp.leaf();
 		}
-		if (tmp.has_branch_path())
+		else if (tmp.has_branch_path())
 		{
-			error = "torrent contains name with directories: '" + m_name + "'";
+			fs::path p;
+			for (fs::path::iterator i = tmp.begin()
+				, end(tmp.end()); i != end; ++i)
+			{
+				if (*i == "." || *i == "..") continue;
+				p /= *i;
+			}
+			m_name = p.string();
+		}
+		if (m_name == ".." || m_name == ".")
+		{
+		
+			error = "invalid 'name' of torrent (possible exploit attempt)";
 			return false;
 		}
 	
diff --git a/test/test_primitives.cpp b/test/test_primitives.cpp
index 15835fe95..b860781fd 100644
--- a/test/test_primitives.cpp
+++ b/test/test_primitives.cpp
@@ -286,9 +286,21 @@ int test_main()
 	torrent["info"] = info;
 
 	torrent_info ti(torrent);
-
+	std::cerr << ti.name() << std::endl;
 	TEST_CHECK(ti.name() == "test1");
 
+	info["name.utf-8"] = "/test1/test2/test3";
+	torrent["info"] = info;
+	torrent_info ti2(torrent);
+	std::cerr << ti2.name() << std::endl;
+	TEST_CHECK(ti2.name() == "test3");
+
+	info["name.utf-8"] = "test2/../test3/.././../../test4";
+	torrent["info"] = info;
+	torrent_info ti3(torrent);
+	std::cerr << ti3.name() << std::endl;
+	TEST_CHECK(ti3.name() == "test2/test3/test4");
+
 	// test kademlia functions
 
 	using namespace libtorrent::dht;