No description
bdd84660c7
When tinc is used in router mode with a TAP device, Ethernet (MAC)
headers are not present in packets flowing over the VPN; it is the
node's responsibility to fill out this header before handing the
packet over to the TAP interface (which expects such headers).
Currently, tinc fills out the destination MAC address of the packet
(otherwise the host would not recognize the packets, and nothing would
work), but it does not fill out the source MAC address. In practice this
doesn't seem to cause any real issues (the host doesn't care about the
source address), but it does look weird when looking at the packets with
a sniffer, and it also result in the following valgrind warning:
==13651== Syscall param write(buf) points to uninitialised byte(s)
==13651== at 0x5C4B620: __write_nocancel (syscall-template.S:81)
==13651== by 0x1445AA: write_packet (device.c:183)
==13651== by 0x118C7C: send_packet (net_packet.c:1259)
==13651== by 0x12B70A: route_ipv4 (route.c:443)
==13651== by 0x12D5F8: route (route.c:971)
==13651== by 0x1152BC: receive_packet (net_packet.c:250)
==13651== by 0x117E1B: receive_sptps_record (net_packet.c:904)
==13651== by 0x1309A8: sptps_receive_data_datagram (sptps.c:488)
==13651== by 0x130A90: sptps_receive_data (sptps.c:508)
==13651== by 0x115569: receive_udppacket (net_packet.c:286)
==13651== by 0x119856: handle_incoming_vpn_data (net_packet.c:1499)
==13651== by 0x10F3DA: event_loop (event.c:287)
==13651== Address 0xffeffea3a is on thread 1's stack
==13651== in frame #6, created by receive_sptps_record (net_packet.c:821)
==13651==
This commit fixes the issue by filling out the source MAC address. It is
generated by negating the last byte of the device MAC address, which is
consistent with what route_arp() does.
In addition, this commit stops route_arp() from filling out the Ethernet
header of the packet - this is the responsibility of send_packet(), not
route().
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| bash_completion.d | ||
| doc | ||
| gui | ||
| m4 | ||
| src | ||
| systemd | ||
| test | ||
| .gitignore | ||
| AUTHORS | ||
| configure.ac | ||
| COPYING | ||
| COPYING.README | ||
| Makefile.am | ||
| NEWS | ||
| README | ||
| README.android | ||
| README.git | ||
| THANKS | ||
This is the README file for tinc version 1.1pre11. Installation instructions may be found in the INSTALL file. tinc is Copyright (C) 1998-2014 by: Ivo Timmermans, Guus Sliepen <guus@tinc-vpn.org>, and others. For a complete list of authors see the AUTHORS file. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. See the file COPYING for more details. This is a pre-release --------------------- Please note that this is NOT a stable release. Until version 1.1.0 is released, please use one of the 1.0.x versions if you need a stable version of tinc. Although tinc 1.1 will be protocol compatible with tinc 1.0.x, the functionality of the tinc program may still change, and the control socket protocol is not fixed yet. Security statement ------------------ This version uses an experimental and unfinished cryptographic protocol. Use it at your own risk. Compatibility ------------- Version 1.1pre11 is compatible with 1.0pre8, 1.0 and later, but not with older versions of tinc. When the ExperimentalProtocol option is used, tinc is still compatible with 1.0.X and 1.1pre11 itself, but not with any other 1.1preX version. Requirements ------------ In order to compile tinc, you will need a GNU C compiler environment. Please ensure you have the latest stable versions of all the required libraries: - OpenSSL (http://www.openssl.org/) version 1.0.0 or later, with support for elliptic curve cryptography (ECC) and Galois counter mode (GCM) enabled. The following libraries are used by default, but can be disabled if necessary: - zlib (http://www.gzip.org/zlib/) - lzo (http://www.oberhumer.com/opensource/lzo/) - ncurses (http://invisible-island.net/ncurses/) - readline (ftp://ftp.gnu.org/pub/gnu/readline/) Features -------- Tinc is a peer-to-peer VPN daemon that supports VPNs with an arbitrary number of nodes. Instead of configuring tunnels, you give tinc the location and public key of a few nodes in the VPN. After making the initial connections to those nodes, tinc will learn about all other nodes on the VPN, and will make connections automatically. When direct connections are not possible, data will be forwarded by intermediate nodes. By default, nodes authenticate each other using 2048 bit RSA (or 521 bit ECDSA*) keys. Traffic is encrypted using Blowfish in CBC mode (or AES-256 in GCM mode*), authenticated using HMAC-SHA1 (or GCM*), and is protected against replay attacks. *) When using the ExperimentalProtocol option. Tinc fully supports IPv6. Tinc can operate in several routing modes. In the default mode, "router", every node is associated with one or more IPv4 and/or IPv6 Subnets. The other two modes, "switch" and "hub", let the tinc daemons work together to form a virtual Ethernet network switch or hub. Normally, when started tinc will detach and run in the background. In a native Windows environment this means tinc will intall itself as a service, which will restart after reboots. To prevent tinc from detaching or running as a service, use the -D option. The status of the VPN can be queried using the "tinc" command, which connects to a running tinc daemon via a control connection. The same tool also makes it easy to start and stop tinc, and to change its configuration.