diff --git a/libtorrent/src/enum_net.cpp b/libtorrent/src/enum_net.cpp
new file mode 100644
index 000000000..54af814d6
--- /dev/null
+++ b/libtorrent/src/enum_net.cpp
@@ -0,0 +1,133 @@
+/*
+
+Copyright (c) 2007, Arvid Norberg
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in
+      the documentation and/or other materials provided with the distribution.
+    * Neither the name of the author nor the names of its
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+#if defined __linux__ || defined __MACH__
+#include <sys/ioctl.h>
+#include <netinet/in.h>
+#include <net/if.h>
+#endif
+
+#include "libtorrent/enum_net.hpp"
+
+namespace libtorrent
+{
+	std::vector<address> const& enum_net_interfaces(asio::io_service& ios, asio::error_code& ec)
+	{
+		static std::vector<address> ret;
+		if (!ret.empty()) return ret;
+
+#if defined __linux__ || defined __MACH__ || defined(__FreeBSD__)
+		int s = socket(AF_INET, SOCK_DGRAM, 0);
+		if (s < 0)
+		{
+			ec = asio::error::fault;
+			return ret;
+		}
+		ifconf ifc;
+		char buf[1024];
+		ifc.ifc_len = sizeof(buf);
+		ifc.ifc_buf = buf;
+		if (ioctl(s, SIOCGIFCONF, &ifc) < 0)
+		{
+			close(s);
+			ec = asio::error::fault;
+			return ret;
+		}
+		close(s);
+
+		char *ifr = (char*)ifc.ifc_req;
+		int remaining = ifc.ifc_len;
+
+		while (remaining)
+		{
+			ifreq const& item = *reinterpret_cast<ifreq*>(ifr);
+			if (item.ifr_addr.sa_family == AF_INET)
+			{
+				ret.push_back(address::from_string(
+					inet_ntoa(((sockaddr_in const*)&item.ifr_addr)->sin_addr)));
+			}
+
+#if defined __MACH__ || defined(__FreeBSD__)
+			int current_size = item.ifr_addr.sa_len + IFNAMSIZ;
+#elif defined __linux__
+			int current_size = sizeof(ifreq);
+#endif
+			ifr += current_size;
+			remaining -= current_size;
+		}
+
+#elif defined WIN32
+
+		SOCKET s = socket(AF_INET, SOCK_DGRAM, 0);
+		if (s == SOCKET_ERROR)
+		{
+			ec = asio::error::fault;
+			return ret;
+		}
+
+		INTERFACE_INFO buffer[30];
+		DWORD size;
+	
+		if (WSAIoctl(s, SIO_GET_INTERFACE_LIST, 0, 0, buffer,
+			sizeof(buffer), &size, 0, 0) != 0)
+		{
+			closesocket(s);
+			ec = asio::error::fault;
+			return ret;
+		}
+		closesocket(s);
+
+		int n = size / sizeof(INTERFACE_INFO);
+
+		for (int i = 0; i < n; ++i)
+		{
+			sockaddr_in *sockaddr = (sockaddr_in*)&buffer[i].iiAddress;
+			address a(address::from_string(inet_ntoa(sockaddr->sin_addr)));
+			if (a == address_v4::any()) continue;
+			ret.push_back(a);
+		}
+
+#else
+		// make a best guess of the interface we're using and its IP
+		udp::resolver r(ios);
+		udp::resolver::iterator i = r.resolve(udp::resolver::query(asio::ip::host_name(), "0"));
+		for (;i != udp::resolver_iterator(); ++i)
+		{
+			ret.push_back(i->endpoint().address());
+		}
+#endif
+		return ret;
+	}
+
+}
+
+