drivers/net/ppp/Kconfig - linux - Git at Google

 # SPDX-License-Identifier: GPL-2.0-only
 #
 # PPP network device configuration
 #

 config PPP
 	tristate "PPP (point-to-point protocol) support"
 	select SLHC
 	help
 	  PPP (Point to Point Protocol) is a newer and better SLIP.  It serves
 	  the same purpose: sending Internet traffic over telephone (and other
 	  serial) lines.  Ask your access provider if they support it, because
 	  otherwise you can't use it; most Internet access providers these
 	  days support PPP rather than SLIP.

 	  To use PPP, you need an additional program called pppd as described
 	  in the PPP-HOWTO, available at
 	  <http://www.tldp.org/docs.html#howto>.  Make sure that you have
 	  the version of pppd recommended in <file:Documentation/Changes>.
 	  The PPP option enlarges your kernel by about 16 KB.

 	  There are actually two versions of PPP: the traditional PPP for
 	  asynchronous lines, such as regular analog phone lines, and
 	  synchronous PPP which can be used over digital ISDN lines for
 	  example.  If you want to use PPP over phone lines or other
 	  asynchronous serial lines, you need to say Y (or M) here and also to
 	  the next option, "PPP support for async serial ports".  For PPP over
 	  synchronous lines, you should say Y (or M) here and to "Support
 	  synchronous PPP", below.

 	  If you said Y to "Version information on all symbols" above, then
 	  you cannot compile the PPP driver into the kernel; you can then only
 	  compile it as a module. To compile this driver as a module, choose M
 	  here. The module will be called ppp_generic.

 if PPP

 config PPP_BSDCOMP
 	tristate "PPP BSD-Compress compression"
 	depends on PPP
 	help
 	  Support for the BSD-Compress compression method for PPP, which uses
 	  the LZW compression method to compress each PPP packet before it is
 	  sent over the wire. The machine at the other end of the PPP link
 	  (usually your ISP) has to support the BSD-Compress compression
 	  method as well for this to be useful. Even if they don't support it,
 	  it is safe to say Y here.

 	  The PPP Deflate compression method ("PPP Deflate compression",
 	  above) is preferable to BSD-Compress, because it compresses better
 	  and is patent-free.

 	  Note that the BSD compression code will always be compiled as a
 	  module; it is called bsd_comp and will show up in the directory
 	  modules once you have said "make modules". If unsure, say N.

 config PPP_DEFLATE
 	tristate "PPP Deflate compression"
 	depends on PPP
 	select ZLIB_INFLATE
 	select ZLIB_DEFLATE
 	help
 	  Support for the Deflate compression method for PPP, which uses the
 	  Deflate algorithm (the same algorithm that gzip uses) to compress
 	  each PPP packet before it is sent over the wire.  The machine at the
 	  other end of the PPP link (usually your ISP) has to support the
 	  Deflate compression method as well for this to be useful.  Even if
 	  they don't support it, it is safe to say Y here.

 	  To compile this driver as a module, choose M here.

 config PPP_FILTER
 	bool "PPP filtering"
 	depends on PPP
 	help
 	  Say Y here if you want to be able to filter the packets passing over
 	  PPP interfaces.  This allows you to control which packets count as
 	  activity (i.e. which packets will reset the idle timer or bring up
 	  a demand-dialed link) and which packets are to be dropped entirely.
 	  You need to say Y here if you wish to use the pass-filter and
 	  active-filter options to pppd.

 	  If unsure, say N.

 config PPP_MPPE
 	tristate "PPP MPPE compression (encryption)"
 	depends on PPP
 	select CRYPTO
 	select CRYPTO_SHA1
 	select CRYPTO_LIB_ARC4
 	help
 	  Support for the MPPE Encryption protocol, as employed by the
 	  Microsoft Point-to-Point Tunneling Protocol.

 	  See http://pptpclient.sourceforge.net/ for information on
 	  configuring PPTP clients and servers to utilize this method.

 config PPP_MULTILINK
 	bool "PPP multilink support"
 	depends on PPP
 	help
 	  PPP multilink is a protocol (defined in RFC 1990) which allows you
 	  to combine several (logical or physical) lines into one logical PPP
 	  connection, so that you can utilize your full bandwidth.

 	  This has to be supported at the other end as well and you need a
 	  version of the pppd daemon which understands the multilink protocol.

 	  If unsure, say N.

 config PPPOATM
 	tristate "PPP over ATM"
 	depends on ATM && PPP
 	help
 	  Support PPP (Point to Point Protocol) encapsulated in ATM frames.
 	  This implementation does not yet comply with section 8 of RFC2364,
 	  which can lead to bad results if the ATM peer loses state and
 	  changes its encapsulation unilaterally.

 config PPPOE
 	tristate "PPP over Ethernet"
 	depends on PPP
 	help
 	  Support for PPP over Ethernet.

 	  This driver requires the latest version of pppd from the CVS
 	  repository at cvs.samba.org.  Alternatively, see the
 	  RoaringPenguin package (<http://www.roaringpenguin.com/pppoe>)
 	  which contains instruction on how to use this driver (under
 	  the heading "Kernel mode PPPoE").

 choice
 	prompt "Number of PPPoE hash bits"
 	default PPPOE_HASH_BITS_4
 	depends on PPPOE
 	help
 		Select the number of bits used for hashing PPPoE interfaces.

 		Larger sizes reduces the risk of hash collisions at the cost
 		of slightly increased memory usage.

 		This hash table is on a per outer ethernet interface.

 config PPPOE_HASH_BITS_1
 	bool "1 bit (2 buckets)"

 config PPPOE_HASH_BITS_2
 	bool "2 bits (4 buckets)"

 config PPPOE_HASH_BITS_4
 	bool "4 bits (16 buckets)"

 config PPPOE_HASH_BITS_8
 	bool "8 bits (256 buckets)"

 endchoice

 config PPPOE_HASH_BITS
 	int
 	default 1 if PPPOE_HASH_BITS_1
 	default 2 if PPPOE_HASH_BITS_2
 	default 4 if PPPOE_HASH_BITS_4
 	default 8 if PPPOE_HASH_BITS_8
 	default 4

 config PPTP
 	tristate "PPP over IPv4 (PPTP)"
 	depends on PPP && NET_IPGRE_DEMUX
 	help
 	  Support for PPP over IPv4.(Point-to-Point Tunneling Protocol)

 	  This driver requires pppd plugin to work in client mode or
 	  modified pptpd (poptop) to work in server mode.
 	  See http://accel-pptp.sourceforge.net/ for information how to
 	  utilize this module.

 config PPPOL2TP
 	tristate "PPP over L2TP"
 	depends on L2TP && PPP
 	help
 	  Support for PPP-over-L2TP socket family. L2TP is a protocol
 	  used by ISPs and enterprises to tunnel PPP traffic over UDP
 	  tunnels. L2TP is replacing PPTP for VPN uses.
 if TTY

 config PPP_ASYNC
 	tristate "PPP support for async serial ports"
 	depends on PPP
 	select CRC_CCITT
 	help
 	  Say Y (or M) here if you want to be able to use PPP over standard
 	  asynchronous serial ports, such as COM1 or COM2 on a PC.  If you use
 	  a modem (not a synchronous or ISDN modem) to contact your ISP, you
 	  need this option.

 	  To compile this driver as a module, choose M here.

 	  If unsure, say Y.

 config PPP_SYNC_TTY
 	tristate "PPP support for sync tty ports"
 	depends on PPP
 	help
 	  Say Y (or M) here if you want to be able to use PPP over synchronous
 	  (HDLC) tty devices, such as the SyncLink adapter. These devices
 	  are often used for high-speed leased lines like T1/E1.

 	  To compile this driver as a module, choose M here.

 endif # TTY

 endif # PPP
	# SPDX-License-Identifier: GPL-2.0-only
	#
	# PPP network device configuration
	#

	config PPP
	tristate "PPP (point-to-point protocol) support"
	select SLHC
	help
	PPP (Point to Point Protocol) is a newer and better SLIP. It serves
	the same purpose: sending Internet traffic over telephone (and other
	serial) lines. Ask your access provider if they support it, because
	otherwise you can't use it; most Internet access providers these
	days support PPP rather than SLIP.

	To use PPP, you need an additional program called pppd as described
	in the PPP-HOWTO, available at
	<http://www.tldp.org/docs.html#howto>. Make sure that you have
	the version of pppd recommended in <file:Documentation/Changes>.
	The PPP option enlarges your kernel by about 16 KB.

	There are actually two versions of PPP: the traditional PPP for
	asynchronous lines, such as regular analog phone lines, and
	synchronous PPP which can be used over digital ISDN lines for
	example. If you want to use PPP over phone lines or other
	asynchronous serial lines, you need to say Y (or M) here and also to
	the next option, "PPP support for async serial ports". For PPP over
	synchronous lines, you should say Y (or M) here and to "Support
	synchronous PPP", below.

	If you said Y to "Version information on all symbols" above, then
	you cannot compile the PPP driver into the kernel; you can then only
	compile it as a module. To compile this driver as a module, choose M
	here. The module will be called ppp_generic.

	if PPP

	config PPP_BSDCOMP
	tristate "PPP BSD-Compress compression"
	depends on PPP
	help
	Support for the BSD-Compress compression method for PPP, which uses
	the LZW compression method to compress each PPP packet before it is
	sent over the wire. The machine at the other end of the PPP link
	(usually your ISP) has to support the BSD-Compress compression
	method as well for this to be useful. Even if they don't support it,
	it is safe to say Y here.

	The PPP Deflate compression method ("PPP Deflate compression",
	above) is preferable to BSD-Compress, because it compresses better
	and is patent-free.

	Note that the BSD compression code will always be compiled as a
	module; it is called bsd_comp and will show up in the directory
	modules once you have said "make modules". If unsure, say N.

	config PPP_DEFLATE
	tristate "PPP Deflate compression"
	depends on PPP
	select ZLIB_INFLATE
	select ZLIB_DEFLATE
	help
	Support for the Deflate compression method for PPP, which uses the
	Deflate algorithm (the same algorithm that gzip uses) to compress
	each PPP packet before it is sent over the wire. The machine at the
	other end of the PPP link (usually your ISP) has to support the
	Deflate compression method as well for this to be useful. Even if
	they don't support it, it is safe to say Y here.

	To compile this driver as a module, choose M here.

	config PPP_FILTER
	bool "PPP filtering"
	depends on PPP
	help
	Say Y here if you want to be able to filter the packets passing over
	PPP interfaces. This allows you to control which packets count as
	activity (i.e. which packets will reset the idle timer or bring up
	a demand-dialed link) and which packets are to be dropped entirely.
	You need to say Y here if you wish to use the pass-filter and
	active-filter options to pppd.

	If unsure, say N.

	config PPP_MPPE
	tristate "PPP MPPE compression (encryption)"
	depends on PPP
	select CRYPTO
	select CRYPTO_SHA1
	select CRYPTO_LIB_ARC4
	help
	Support for the MPPE Encryption protocol, as employed by the
	Microsoft Point-to-Point Tunneling Protocol.

	See http://pptpclient.sourceforge.net/ for information on
	configuring PPTP clients and servers to utilize this method.

	config PPP_MULTILINK
	bool "PPP multilink support"
	depends on PPP
	help
	PPP multilink is a protocol (defined in RFC 1990) which allows you
	to combine several (logical or physical) lines into one logical PPP
	connection, so that you can utilize your full bandwidth.

	This has to be supported at the other end as well and you need a
	version of the pppd daemon which understands the multilink protocol.

	If unsure, say N.

	config PPPOATM
	tristate "PPP over ATM"
	depends on ATM && PPP
	help
	Support PPP (Point to Point Protocol) encapsulated in ATM frames.
	This implementation does not yet comply with section 8 of RFC2364,
	which can lead to bad results if the ATM peer loses state and
	changes its encapsulation unilaterally.

	config PPPOE
	tristate "PPP over Ethernet"
	depends on PPP
	help
	Support for PPP over Ethernet.

	This driver requires the latest version of pppd from the CVS
	repository at cvs.samba.org. Alternatively, see the
	RoaringPenguin package (<http://www.roaringpenguin.com/pppoe>)
	which contains instruction on how to use this driver (under
	the heading "Kernel mode PPPoE").

	choice
	prompt "Number of PPPoE hash bits"
	default PPPOE_HASH_BITS_4
	depends on PPPOE
	help
	Select the number of bits used for hashing PPPoE interfaces.

	Larger sizes reduces the risk of hash collisions at the cost
	of slightly increased memory usage.

	This hash table is on a per outer ethernet interface.

	config PPPOE_HASH_BITS_1
	bool "1 bit (2 buckets)"

	config PPPOE_HASH_BITS_2
	bool "2 bits (4 buckets)"

	config PPPOE_HASH_BITS_4
	bool "4 bits (16 buckets)"

	config PPPOE_HASH_BITS_8
	bool "8 bits (256 buckets)"

	endchoice

	config PPPOE_HASH_BITS
	int
	default 1 if PPPOE_HASH_BITS_1
	default 2 if PPPOE_HASH_BITS_2
	default 4 if PPPOE_HASH_BITS_4
	default 8 if PPPOE_HASH_BITS_8
	default 4

	config PPTP
	tristate "PPP over IPv4 (PPTP)"
	depends on PPP && NET_IPGRE_DEMUX
	help
	Support for PPP over IPv4.(Point-to-Point Tunneling Protocol)

	This driver requires pppd plugin to work in client mode or
	modified pptpd (poptop) to work in server mode.
	See http://accel-pptp.sourceforge.net/ for information how to
	utilize this module.

	config PPPOL2TP
	tristate "PPP over L2TP"
	depends on L2TP && PPP
	help
	Support for PPP-over-L2TP socket family. L2TP is a protocol
	used by ISPs and enterprises to tunnel PPP traffic over UDP
	tunnels. L2TP is replacing PPTP for VPN uses.
	if TTY

	config PPP_ASYNC
	tristate "PPP support for async serial ports"
	depends on PPP
	select CRC_CCITT
	help
	Say Y (or M) here if you want to be able to use PPP over standard
	asynchronous serial ports, such as COM1 or COM2 on a PC. If you use
	a modem (not a synchronous or ISDN modem) to contact your ISP, you
	need this option.

	To compile this driver as a module, choose M here.

	If unsure, say Y.

	config PPP_SYNC_TTY
	tristate "PPP support for sync tty ports"
	depends on PPP
	help
	Say Y (or M) here if you want to be able to use PPP over synchronous
	(HDLC) tty devices, such as the SyncLink adapter. These devices
	are often used for high-speed leased lines like T1/E1.

	To compile this driver as a module, choose M here.

	endif # TTY

	endif # PPP