xisp user dialup.

Hello,
xisp is a dialup gui tool which does not rely on gtk or qt libs.

to enable ordinary users to dialup the xisp documentation recommends
making /usr/sbin/pppd suid (4755) and creating a modem group "uucp".

I have done this and found that xisp works for ordinary users only
if pppd has been started and then stopped first by root.
ie - a user cannot use xisp to start pppd first before root, root has
to start/stop a pppd session and then users can use xisp after that as
long as the machine is up.

# xisp messages to user attemping dialup before root are-

connection initiated.
(30 sec timeout delay)
action terminated.
"Failed to start xisp for unknown reasons
(pppd daemon detached with status 0)"


I am using root to start and stop 'ppp-go' in console first so then users
can use xisp in their desktop.The modem is a lucent 56k on /dev/ttyLT0.
The distro is slackware-9.1.

Any ideas why the root pppd session is required here. I want xisp to be
user dialup without root having to initialse a pppd connection.

the only notable difference I can find is that the generic ppp module
will load but not the lt_serial, lt_modem modules for ordinary users
trying a dialup before root.

thanks for any suggestions,
keith.


##### device and fie permissions are as follows.


# modem device.
crw-rw---- 1 root uucp /dev/ttyLT0

# executables
-rwsr-x--- 1 root uucp /usr/sbin/pppd*
-r-xr-x--- 1 root uucp /usr/sbin/chat*
-rwxr-x--- 1 root uucp /usr/X11R6/bin/xisp*

# /etc/ppp
-rw------- 1 root uucp chap-secrets
-rw------- 1 root root connect-errors
-rwxr-xr-x 1 root uucp ip-down*
-rwxr-xr-x 1 root root ip-down.bak*
-rwxr-xr-x 1 root uucp ip-up*
-rwxr-xr-x 1 root root ip-up.bak*
-rw-rw---- 1 root uucp options
-rw------- 1 root root options.demand
-rw------- 1 root uucp pap-secrets
-rw------- 1 root root pppscript
-rw------- 1 root root pppsetup.txt
-rwxr-x--- 1 root uucp xispdial*
-rwxr-x--- 1 root uucp xispterm*


#/etc/ppp/peers
-rw-rw---- 1 root uucp xisp_dialer
-rw-rw---- 1 root uucp xisp_ttyLT0

#/usr/local/bin - two xisp executables for pid and record.
-rwxr-x--- 1 root uucp xispid*
-rwxr-x--- 1 root uucp xisprccv*



################

#
# /var/log/messages for failed user xisp dialup -

May 30 09:04:46 tui kernel: PPP generic driver version 2.4.2
May 30 09:04:46 tui pppd[462]: pppd 2.4.1 started by kth, uid 500
May 30 09:04:46 tui pppd[462]: Exit.
May 30 09:04:46 tui pppd[462]: pppd 2.4.1 started by kth, uid 500
May 30 09:04:46 tui pppd[462]: Exit.



#
# root dialup with 'ppp-go'-

May 30 09:11:09 tui pppd[478]: pppd 2.4.1 started by root, uid 0
May 30 09:11:10 tui kernel: Loading Lucent Modem Controller driver version 8.26
May 30 09:11:10 tui kernel: Detected Parameters Irq=9 BaseAddress=0xdc00
ComAddress=0xdff0
May 30 09:11:10 tui kernel: Lucent Modem Interface driver version 8.26
(2002-11-04) with SHARE_IRQ enabled
May 30 09:11:10 tui kernel: ttyLT00 at 0xdc00 (irq = 9) is a Lucent Modem
May 30 09:11:10 tui insmod: Warning: loading /lib/modules/2.4.22/ltmodem
/lt_modem.o will taint the kernel: non-GPL license - UNKNOWN
May 30 09:11:10 tui insmod: See http://www.tux.org/lkml/#export-tainted
for information about tainted modules
May 30 09:11:10 tui insmod: Module lt_modem loaded, with warnings
May 30 09:11:10 tui insmod: Module lt_serial loaded, with warnings
May 30 09:11:11 tui chat[481]: timeout set to 30 seconds
May 30 09:11:11 tui chat[481]: abort on (ERROR)
May 30 09:11:11 tui chat[481]: abort on (BUSY)
May 30 09:11:11 tui chat[481]: abort on (NO CARRIER)
May 30 09:11:11 tui chat[481]: abort on (NO DIALTONE)
May 30 09:11:11 tui chat[481]: send (AT&FH0^M)
May 30 09:11:11 tui chat[481]: expect (OK)
May 30 09:11:11 tui chat[481]: AT&FH0^M^M
May 30 09:11:11 tui chat[481]: OK
May 30 09:11:11 tui chat[481]: -- got it
May 30 09:11:11 tui chat[481]: send (atdt086304135^M)
May 30 09:11:11 tui chat[481]: timeout set to 30 seconds
May 30 09:11:11 tui chat[481]: expect (CONNECT)
May 30 09:11:11 tui chat[481]: ^M
May 30 09:11:38 tui chat[481]: atdt086304135^M^M
May 30 09:11:38 tui chat[481]: CONNECT
May 30 09:11:38 tui chat[481]: -- got it
May 30 09:11:38 tui pppd[478]: Serial connection established.
May 30 09:11:38 tui pppd[478]: Using interface ppp0
May 30 09:11:38 tui pppd[478]: Connect: ppp0 <--> /dev/ttyLT0
May 30 09:11:40 tui kernel: PPP BSD Compression module registered
May 30 09:11:40 tui kernel: PPP Deflate Compression module registered
May 30 09:11:40 tui pppd[478]: local IP address 210.185.4.31
May 30 09:11:40 tui pppd[478]: remote IP address 192.168.251.45



#
# After the root pppd session users can dialup with xisp.

May 30 09:24:55 tui pppd[623]: pppd 2.4.1 started by kth, uid 500
May 30 09:25:25 tui pppd[623]: Serial connection established.
May 30 09:25:25 tui pppd[623]: Using interface ppp0
May 30 09:25:25 tui pppd[623]: Connect: ppp0 <--> /dev/ttyLT0
May 30 09:25:27 tui pppd[623]: local IP address 210.185.7.20
May 30 09:25:27 tui pppd[623]: remote IP address 192.168.251.45
May 30 09:25:45 tui pppd[623]: Terminating on signal 2.
May 30 09:25:45 tui pppd[623]: Connection terminated.
May 30 09:25:45 tui pppd[623]: Connect time 0.4 minutes.
May 30 09:25:45 tui pppd[623]: Sent 55 bytes, received 42 bytes.
May 30 09:25:45 tui pppd[623]: Hangup (SIGHUP)
May 30 09:25:45 tui pppd[623]: Exit.

Otako <(E-Mail Removed)> wrote:

> xisp is a dialup gui tool which does not rely on gtk or qt libs.

> to enable ordinary users to dialup the xisp documentation recommends
> making /usr/sbin/pppd suid (4755) and creating a modem group "uucp".

> I have done this and found that xisp works for ordinary users only
> if pppd has been started and then stopped first by root.
> ie - a user cannot use xisp to start pppd first before root, root has
> to start/stop a pppd session and then users can use xisp after that as
> long as the machine is up.

> # xisp messages to user attemping dialup before root are-

> connection initiated.
> (30 sec timeout delay)
> action terminated.
> "Failed to start xisp for unknown reasons
> (pppd daemon detached with status 0)"

[snip]

> ##### device and fie permissions are as follows.
> # modem device.
> crw-rw---- 1 root uucp /dev/ttyLT0

Ordinary users that are not also in the group uucp cannot read or write
to this device file. To make a landline PPP connection both are required.

Either make this

crw-rw-rw- 1 root uucp /dev/ttyLT0

or change the group name to users, or put the users you want to use
"xisp" into the uucp group. It you just change permissions for
"others" then you may find, from time to time, that the permissions
change back to no read-write for ordinary users. Not all programs
that use the device file may reset the permissions to the those it
had before they used it.

You also write a wrapper program (in C) for starting pppd and set that
SUID root.

> # executables
> -rwsr-x--- 1 root uucp /usr/sbin/pppd*
> -r-xr-x--- 1 root uucp /usr/sbin/chat*
> -rwxr-x--- 1 root uucp /usr/X11R6/bin/xisp*

Just setting the pppd execute permission to SUID root won't work; pppd
knows the difference between being run by root and being run as root...

[snip]

> # /var/log/messages for failed user xisp dialup -
> May 30 09:04:46 tui kernel: PPP generic driver version 2.4.2
> May 30 09:04:46 tui pppd[462]: pppd 2.4.1 started by kth, uid 500
> May 30 09:04:46 tui pppd[462]: Exit.
> May 30 09:04:46 tui pppd[462]: pppd 2.4.1 started by kth, uid 500
> May 30 09:04:46 tui pppd[462]: Exit.

.... as this demonstrates.

-- Clifford Kite Email: "echo xvgr_yvahk-(E-Mail Removed)|rot13"
PPP-Q&A links, downloads: http://ckite.no-ip.net/
/* To extract lines: View file with "vi -R". Move cursor to first line.
Press "v". Move cursor to mark lines (Esc unmarks). Write lines to
fubar with ":w fubar <Enter>". Exit with ":q <Enter>". */

On 2004-06-02, Clifford wrote:
>> crw-rw---- 1 root uucp /dev/ttyLT0
> Ordinary users that are not also in the group uucp cannot read or write
> to this device file. To make a landline PPP connection both are required.

I had users in the uucp group as recommented by the xisp docs.

> You also write a wrapper program (in C) for starting pppd and set that
> SUID root.

thanks for the advice, I'll try some perl wrapper scripts that google
came up with.

Otako <(E-Mail Removed)> wrote:
> On 2004-06-02, Clifford wrote:
>>> crw-rw---- 1 root uucp /dev/ttyLT0
>> Ordinary users that are not also in the group uucp cannot read or write
>> to this device file. To make a landline PPP connection both are required.

> I had users in the uucp group as recommented by the xisp docs.

>> You also write a wrapper program (in C) for starting pppd and set that
>> SUID root.

> thanks for the advice, I'll try some perl wrapper scripts that google
> came up with.

Here's another thought, although I'd prefer the wrapper rather than give
regular users so much power:

chmod 4755 /sbin/modprobe

--
Clifford Kite Email: "echo xvgr_yvahk-(E-Mail Removed)|rot13"
PPP-Q&A links, downloads: http://ckite.no-ip.net/
/* Speak softly and carry a +6 two-handed sword. */