feature request (if possible): symlink name in environment

feature request (if possible): symlink name in environment

[martin f krafft]

[-- Attachment #1: Type: text/plain, Size: 902 bytes --]

I am not sure this is possible, but if it is...

Would you consider making the name of any symlinks to be added to
a device available in the environment (e.g. a :-separated list in
$SYMLINKS), when the /dev/dev.d hooks are called?

This would allow me to write a hook for permissions.d, making it
optional and still supporting all it should be able to do.

Thanks,

-- 
martin;              (greetings from the heart of the sun.)
  \____ echo mailto: !#^."<*>"|tr "<*> mailto:" net@madduck
 
invalid/expired pgp subkeys? use subkeys.pgp.net as keyserver!
spamtraps: madduck.bogus@madduck.net
 
"with sufficient thrust, pigs fly just fine. however, this is not
 necessarily a good idea. it is hard to be sure where they are going
 to land, and it could be dangerous sitting under them as they fly
 overhead."
                                                           -- rfc 1925

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

Re: feature request (if possible): symlink name in environment

[Kay Sievers]

On Tue, 2004-12-21 at 16:02 +0100, martin f krafft wrote:
> I am not sure this is possible, but if it is...
> 
> Would you consider making the name of any symlinks to be added to
> a device available in the environment (e.g. a :-separated list in
> $SYMLINKS), when the /dev/dev.d hooks are called?
> 
> This would allow me to write a hook for permissions.d, making it
> optional and still supporting all it should be able to do.

Use udevinfo in the dev.d/ script and ask with the DEVPATH for the
symlinks:

  [kay@pim ~]$ udevinfo -r -q symlink -p /class/video4linux/video0
  /dev/camera0 /dev/kamera0 /dev/videocam0 /dev/webcam0 

Kay



-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: feature request (if possible): symlink name in environment

[martin f krafft]

[-- Attachment #1.1: Type: text/plain, Size: 922 bytes --]

also sprach Kay Sievers <kay.sievers@vrfy.org> [2004.12.21.1611 +0100]:
> Use udevinfo in the dev.d/ script and ask with the DEVPATH for the
> symlinks:
> 
>   [kay@pim ~]$ udevinfo -r -q symlink -p /class/video4linux/video0
>   /dev/camera0 /dev/kamera0 /dev/videocam0 /dev/webcam0 

Awesome. I hacked together the attached file. However, it does not
seem to be working. The logs indicate that everything goes by plan,
but the permissions are not changed.

Am I thus to assume that the hooks run before the rules.d
permissions are applied?

-- 
martin;              (greetings from the heart of the sun.)
  \____ echo mailto: !#^."<*>"|tr "<*> mailto:" net@madduck
 
invalid/expired pgp subkeys? use subkeys.pgp.net as keyserver!
spamtraps: madduck.bogus@madduck.net
 
"die philosophie ist eine art rache an der wirklichkeit."
                                                 - friedrich nietzsche

[-- Attachment #1.2: permissions.dev --]
[-- Type: text/plain, Size: 724 bytes --]

#!/bin/bash -e

[[ $ACTION = add ]] || exit 0

UDEV_CONF=/etc/udev/udev.conf
[[ -f $UDEV_CONF ]] && . $UDEV_CONF
[[ -z $udev_permissions ]] && udev_permissions=/etc/udev/permissions.d

REFS="$DEVNAME $(udevinfo -r -q symlink -p $DEVPATH)"
logger -t $0 -p daemon.debug -- "checking references for $DEVNAME for permission
s: $REFS"
for node in $REFS; do
  [[ ! -b $node ]] && [[ ! -c $node ]] && [[ ! -L $node ]] && continue
  name=${node#/dev/}
  perms=$(grep -h "^$name" $udev_permissions/*.permissions | tail -1)
  set -- $(echo ${perms//:/ })
  [[ -z $2 ]] && continue
  logger -t $0 -p daemon.debug -- "applying permissions $2:$3:$4 to $DEVNAME (due to reference '$1')..."
  chgrp $2:$3 $DEVNAME
  chmod $4 $DEVNAME
done

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

Re: feature request (if possible): symlink name in environment

[Greg KH]

On Tue, Dec 21, 2004 at 04:38:44PM +0100, martin f krafft wrote:
> also sprach Kay Sievers <kay.sievers@vrfy.org> [2004.12.21.1611 +0100]:
> > Use udevinfo in the dev.d/ script and ask with the DEVPATH for the
> > symlinks:
> > 
> >   [kay@pim ~]$ udevinfo -r -q symlink -p /class/video4linux/video0
> >   /dev/camera0 /dev/kamera0 /dev/videocam0 /dev/webcam0 
> 
> Awesome. I hacked together the attached file. However, it does not
> seem to be working. The logs indicate that everything goes by plan,
> but the permissions are not changed.
> 
> Am I thus to assume that the hooks run before the rules.d
> permissions are applied?

No, the hook should run after.

greg k-h


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: feature request (if possible): symlink name in environment

[martin f krafft]

[-- Attachment #1: Type: text/plain, Size: 1011 bytes --]

also sprach Greg KH <greg@kroah.com> [2004.12.21.1704 +0100]:
> No, the hook should run after.

This is what I gathered from the code as well. However, it does not
appear to work.

Would you consider trying it out? Maybe I am just on crack...

Drop it into /etc/dev.d/default/permissions.dev with 755
permissions.

Create a file in permissions.d, the way it used to be.

See if the permissions are applied (symlinks should be followed, and
the last symlink shown by

  udevinfo -r -q symlink -p $DEVPATH

has the highest priority.

Thanks,

-- 
martin;              (greetings from the heart of the sun.)
  \____ echo mailto: !#^."<*>"|tr "<*> mailto:" net@madduck
 
invalid/expired pgp subkeys? use subkeys.pgp.net as keyserver!
spamtraps: madduck.bogus@madduck.net
 
"i like wagner's music better than anybody's. it is so loud that one
 can talk the whole time without other people hearing what one says."
                                                        -- oscar wilde

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

Re: feature request (if possible): symlink name in environment

[Kay Sievers]

On Tue, 2004-12-21 at 17:08 +0100, martin f krafft wrote:
> also sprach Greg KH <greg@kroah.com> [2004.12.21.1704 +0100]:
> > No, the hook should run after.
> 
> This is what I gathered from the code as well. However, it does not
> appear to work.
> 
> Would you consider trying it out? Maybe I am just on crack...
> 
> Drop it into /etc/dev.d/default/permissions.dev with 755
> permissions.
> 
> Create a file in permissions.d, the way it used to be.
> 
> See if the permissions are applied (symlinks should be followed, and
> the last symlink shown by
> 
>   udevinfo -r -q symlink -p $DEVPATH
> 
> has the highest priority.

Any other scripts running after that, which change may it back?

And
  name=${node#/dev/}
  perms=$(grep -h "^$name" $udev_permissions/*.permissions | tail -1)

will not return the "name*:..." line for a device named "name0" what it
should, right?

Kay



-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: feature request (if possible): symlink name in environment

[martin f krafft]

[-- Attachment #1: Type: text/plain, Size: 1125 bytes --]

also sprach Kay Sievers <kay.sievers@vrfy.org> [2004.12.21.1836 +0100]:
> Any other scripts running after that, which change may it back?

Not that I know. Maybe permissions.d itself is getting int the way,
but the problem persists if I clean out everything else from
permissions.d. Apart, those should (have) be(en) applied before the
dev.d hooks, right?

> And
>   name=${node#/dev/}
>   perms=$(grep -h "^$name" $udev_permissions/*.permissions | tail -1)
> 
> will not return the "name*:..." line for a device named "name0" what it
> should, right?

Good spot. The final colon ':' should be part of the regexp:

>   perms=$(grep -h "^${name}:" $udev_permissions/*.permissions | tail -1)

Does it work for anyone yet?

-- 
martin;              (greetings from the heart of the sun.)
  \____ echo mailto: !#^."<*>"|tr "<*> mailto:" net@madduck
 
invalid/expired pgp subkeys? use subkeys.pgp.net as keyserver!
spamtraps: madduck.bogus@madduck.net
 
"common sense is the collection of prejudices
 acquired by age eighteen."
                                                    -- albert einstein

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]