| # SPDX-License-Identifier: GPL-2.0-only |
| # |
| # Layer Two Tunneling Protocol (L2TP) |
| # |
| |
| menuconfig L2TP |
| tristate "Layer Two Tunneling Protocol (L2TP)" |
| depends on (IPV6 || IPV6=n) |
| depends on INET |
| select NET_UDP_TUNNEL |
| help |
| Layer Two Tunneling Protocol |
| |
| From RFC 2661 <http://www.ietf.org/rfc/rfc2661.txt>. |
| |
| L2TP facilitates the tunneling of packets across an |
| intervening network in a way that is as transparent as |
| possible to both end-users and applications. |
| |
| L2TP is often used to tunnel PPP traffic over IP |
| tunnels. One IP tunnel may carry thousands of individual PPP |
| connections. L2TP is also used as a VPN protocol, popular |
| with home workers to connect to their offices. |
| |
| L2TPv3 allows other protocols as well as PPP to be carried |
| over L2TP tunnels. L2TPv3 is defined in RFC 3931 |
| <http://www.ietf.org/rfc/rfc3931.txt>. |
| |
| The kernel component handles only L2TP data packets: a |
| userland daemon handles L2TP the control protocol (tunnel |
| and session setup). One such daemon is OpenL2TP |
| (http://openl2tp.org/). |
| |
| If you don't need L2TP, say N. To compile all L2TP code as |
| modules, choose M here. |
| |
| config L2TP_DEBUGFS |
| tristate "L2TP debugfs support" |
| depends on L2TP && DEBUG_FS |
| help |
| Support for l2tp directory in debugfs filesystem. This may be |
| used to dump internal state of the l2tp drivers for problem |
| analysis. |
| |
| If unsure, say 'Y'. |
| |
| To compile this driver as a module, choose M here. The module |
| will be called l2tp_debugfs. |
| |
| config L2TP_V3 |
| bool "L2TPv3 support" |
| depends on L2TP |
| help |
| Layer Two Tunneling Protocol Version 3 |
| |
| From RFC 3931 <http://www.ietf.org/rfc/rfc3931.txt>. |
| |
| The Layer Two Tunneling Protocol (L2TP) provides a dynamic |
| mechanism for tunneling Layer 2 (L2) "circuits" across a |
| packet-oriented data network (e.g., over IP). L2TP, as |
| originally defined in RFC 2661, is a standard method for |
| tunneling Point-to-Point Protocol (PPP) [RFC1661] sessions. |
| L2TP has since been adopted for tunneling a number of other |
| L2 protocols, including ATM, Frame Relay, HDLC and even raw |
| ethernet frames. |
| |
| If you are connecting to L2TPv3 equipment, or you want to |
| tunnel raw ethernet frames using L2TP, say Y here. If |
| unsure, say N. |
| |
| config L2TP_IP |
| tristate "L2TP IP encapsulation for L2TPv3" |
| depends on L2TP_V3 |
| help |
| Support for L2TP-over-IP socket family. |
| |
| The L2TPv3 protocol defines two possible encapsulations for |
| L2TP frames, namely UDP and plain IP (without UDP). This |
| driver provides a new L2TPIP socket family with which |
| userspace L2TPv3 daemons may create L2TP/IP tunnel sockets |
| when UDP encapsulation is not required. When L2TP is carried |
| in IP packets, it used IP protocol number 115, so this port |
| must be enabled in firewalls. |
| |
| To compile this driver as a module, choose M here. The module |
| will be called l2tp_ip. |
| |
| config L2TP_ETH |
| tristate "L2TP ethernet pseudowire support for L2TPv3" |
| depends on L2TP_V3 |
| help |
| Support for carrying raw ethernet frames over L2TPv3. |
| |
| From RFC 4719 <http://www.ietf.org/rfc/rfc4719.txt>. |
| |
| The Layer 2 Tunneling Protocol, Version 3 (L2TPv3) can be |
| used as a control protocol and for data encapsulation to set |
| up Pseudowires for transporting layer 2 Packet Data Units |
| across an IP network [RFC3931]. |
| |
| This driver provides an ethernet virtual interface for each |
| L2TP ethernet pseudowire instance. Standard Linux tools may |
| be used to assign an IP address to the local virtual |
| interface, or add the interface to a bridge. |
| |
| If you are using L2TPv3, you will almost certainly want to |
| enable this option. |
| |
| To compile this driver as a module, choose M here. The module |
| will be called l2tp_eth. |
