spppcontrol(8)

NAME

spppcontrol - display or set parameters for an sppp inter

face

SYNOPSIS

spppcontrol [-v] ifname [parameter[=value]] [...]

DESCRIPTION

The sppp(4) driver might require a number of additional ar

guments or

optional parameters besides the settings that can be adjust

ed with

ifconfig(8). These are things like authentication protocol

parameters,

but also other tunable configuration variables. The

spppcontrol utility

can be used to display the current settings, or adjust these

parameters

as required.

For whatever intent spppcontrol is being called, at least

the parameter

ifname needs to be specified, naming the interface for which

the settings

are to be performed or displayed. Use ifconfig(8), or net

stat(1) to see

which interfaces are available.

If no other parameter is given, spppcontrol will just list

the current

settings for ifname and exit. The reported settings include

the current

PPP phase the interface is in, which can be one of the names

dead,

establish, authenticate, network, or terminate. If an au

thentication

protocol is configured for the interface, the name of the

protocol to be

used, as well as the system name to be used or expected will

be displayed, plus any possible options to the authentication pro

tocol if

applicable. Note that the authentication secrets (sometimes

also called

keys) are not being returned by the underlying system call,

and are thus

not displayed.

If any additional parameter is supplied, superuser privi

leges are

required, and the command works in the ``set'' mode. This

is normally

done quietly, unless the option -v is also enabled, which

will cause a

final printout of the settings as described above once all

other actions

have been taken. Use of this mode will be rejected if the

interface is

currently in any other phase than dead. Note that you can

force an

interface into dead phase by calling ifconfig(8) with the

parameter down.

The currently supported parameters include:

authproto=protoname

Set both, his and my authentication protocol

to protoname.

The protocol name can be one of ``chap'',

``pap'', or

``none''. In the latter case, the use of an

authentication

protocol will be turned off for the named in

terface. This

has the side-effect of clearing the other au

thenticationrelated parameters for this interface as well

(i.e., system

name and authentication secret will be forgot

ten).

myauthproto=protoname

Same as above, but only for my end of the

link. I.e., this

is the protocol when remote is authenticator,

and I am the

peer required to authenticate.

hisauthproto=protoname

Same as above, but only for his end of the

link.

myauthname=name

Set my system name for the authentication pro

tocol.

hisauthname=name

Set his system name for the authentication

protocol. For

CHAP, this will only be used as a hint, caus

ing a warning

message if remote did supply a different name.

For PAP, it

is the name remote must use to authenticate

himself (in

connection with his secret).

myauthsecret=secret

Set my secret (key, password) for use in the

authentication

phase. For CHAP, this will be used to compute

the response

hash value, based on remote's challenge. For

PAP, it will

be transmitted as plain text together with the

system name.

Do not forget to quote the secrets from the

shell if they

contain shell metacharacters (or white space).

myauthkey=secret

Same as above.

hisauthsecret=secret

Same as above, to be used if we are an authen

ticator and

the remote peer needs to authenticate.

hisauthkey=secret

Same as above.

callin Require remote to authenticate himself only

when he is

calling in, but not when we are caller. This

is required

for some peers that do not implement the au

thentication

protocols symmetrically (like Ascend routers,

for example).

always The opposite of callin. Require remote to al

ways authenti

cate, regardless of which side is placing the

call. This

is the default, and will not be explicitly

displayed in the

``list'' mode.

norechallenge

Only meaningful with CHAP. Do not re-chal

lenge peer once

the initial CHAP handshake was successful.

Used to work

around broken peer implementations that cannot

grok being

re-challenged once the connection is up.

rechallenge

With CHAP, send re-challenges at random inter

vals while the

connection is in network phase. (The inter

vals are currently in the range of 300 through approxi

mately 800 seconds.) This is the default, and will not be

explicitly

displayed in the ``list'' mode.

lcp-timeout=timeout-value

Allows to change the value of the LCP restart

timer. Values are specified in milliseconds. The value

must be

between 10 and 20000 ms, defaulting to 3000

ms.

enable-vj

Enable negotiation of Van Jacobsen header com

pression.

(Enabled by default.)

disable-vj

Disable negotiation of Van Jacobsen header

compression.

enable-ipv6

Enable negotiation of the IPv6 network control

protocol.

(Enabled by default if the kernel has IPv6 en

abled.)

disable-ipv6

Disable negotiation of the IPv6 network con

trol protocol.

Since every IPv4 interface in an IPv6-enabled

kernel automatically gets an IPv6 address assigned, this

option provides for a way to administratively prevent

the link from

attempting to negotiate IPv6. Note that ini

tialization of

an IPv6 interface causes a multicast packet to

be sent,

which can cause unwanted traffic costs (for

dial-on-demand

interfaces).

EXAMPLES

# spppcontrol bppp0

bppp0: phase=dead

myauthproto=chap myauthname="uriah"

hisauthproto=chap hisauthname="ifb-gw" norechallenge

lcp-timeout=3000

enable-vj

enable-ipv6

Display the settings for bppp0. The interface is currently

in dead

phase, i.e., the LCP layer is down, and no traffic is possi

ble. Both

ends of the connection use the CHAP protocol, my end tells

remote the

system name ``uriah'', and remote is expected to authenti

cate by the name

``ifb-gw''. Once the initial CHAP handshake was successful,

no further

CHAP challenges will be transmitted. There are supposedly

some known

CHAP secrets for both ends of the link which are not being

shown.

# spppcontrol bppp0 authproto=chap

myauthname=uriah myauthsecret='some secret' hisauth

name=ifb-gw hisauthsecret='another' norechallenge

A possible call to spppcontrol that could have been used to

bring the

interface into the state shown by the previous example.

SEE ALSO

netstat(1), sppp(4), ifconfig(8)

B. Lloyd and W. Simpson, PPP Authentication Protocols, RFC

1334.

W. Simpson, Editor, The Point-to-Point Protocol (PPP), RFC

1661.

W. Simpson, PPP Challenge Handshake Authentication Protocol

(CHAP), RFC

1994.

HISTORY

The spppcontrol utility appeared in FreeBSD 3.0.

AUTHORS

The program was written by Jorg Wunsch, Dresden.

BSD December 30, 2001

BSD