Created attachment 8894 [details]
journal of dragon player run

Works here with both Dragon and VLC.  Note that your user has to be a member of the cdrom group, since the player devices are created with ownership root:cdrom.

then it is possible that the install didn't add user to that group by default.  This will be an abrasion for most users.

(In reply to Frank Griffin from comment #2)
> Works here with both Dragon and VLC.  Note that your user has to be a member
> of the cdrom group, since the player devices are created with ownership
> root:cdrom.

@ Brian

Does that fix it for you?

(User marja isn't a member of the cdrom group, but I had no problem starting "Murder on the Orient Express" from DVD just now.)

CC: (none) => marja11

(different region, of course)

It pulls up the menu on another disk, but then immediately stops when it gets into the movie.  Very much a blocked region.

Yes - I added the user to the groups.

(In reply to Brian Rockwell from comment #6)
> It pulls up the menu on another disk, but then immediately stops when it
> gets into the movie.  Very much a blocked region.


I can't imagine that would show like this in the log:


Jan 24 12:04:48 localhost kernel: blk_update_request: I/O error, dev sr0, sector 138236
Jan 24 12:04:48 localhost kernel: Buffer I/O error on dev sr0, logical block 34559, async page read

Maybe something else is going on?

CC'ing the kernel maintainers 


> 
> Yes - I added the user to the groups.

CC: (none) => kernel

The DVD I tested with was a region 0 (play everywhere), but in my experience at least VLC pays no attention to the region code, and I suspect that's the norm for most FOSS PC players.  Legally, you're supposed to have a license from the DVD consortium to decode and play DVDs, and to get one you have to pay a fee and sign a contract saying that you'll honor region codes (among other things).

No FOSS player bothers with this, so I doubt they would honor region codes either.

After adding the user to cdrom, did you totally log off the user from both the desktop and any tty shells and the log in again ?

If so, try running vlc from the command line and post the stdout/stderr.

The point of the cdrom group (and many others like it in the Unix world) was that on multi-user Unix systems (like university systems where all students had accounts), there were relatively few users that you wanted to have access to specialized hardware like CD/DVD drives, because for reading you would somehow have to get your optical disk to the operator for loading, and for burning you would have to supply blanks to the operator, etc.  So access was restricted by group and the sysadmin would have to take action to give you access to the device.  Same for scanners, etc.

For personal Linux, it might make sense to have the single user defined during a classical install be automatically enrolled in a handful of commonly-needed groups like cdrom, but in general it should be left to the sysadmin to grant these permissions explicitly.

Place the disk in the drive, and try to use your favorite utility (k3b, brasero) to read the disk and create an ISO file on disk.  If there really is an I/O error on the disk, it should show up here.  
 
You can't just try "dd if=/dev/srX of=/dev/null" because the manufacturers of PC optical drives *do* have to get licenses from the DVD Consortium and require software to provide the dvdcss key set in order to read raw blocks from the device.  FOSS players/burners/whatever use libdvdcss to do this (illegal in some places, which is why it's in tainted).

CC: (none) => ftg

(In reply to Marja van Waes from comment #4)
> (User marja isn't a member of the cdrom group, but I had no problem starting
> "Murder on the Orient Express" from DVD just now.)

Interesting, because on my cauldron the optical drive devices are defined as:

[root@ftglap ~]# ls -l /dev/sr*
brw-rw----+ 1 root cdrom 11, 0 Jan 21 15:46 /dev/sr0

so if you're not root or in cdrom, you should be denied.

OK, I should have looked at the attachment:

Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 Sense Key : Illegal Request [current] 
Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 Add. Sense: Read of scrambled sector without authentication
Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 CDB: Read(10) 28 00 00 02 b3 b3 00 00 01 00
Jan 24 12:01:07 localhost kernel: blk_update_request: 3 callbacks suppressed
Jan 24 12:01:07 localhost kernel: blk_update_request: I/O error, dev sr0, sector 708300
Jan 24 12:01:07 localhost kernel: buffer_io_error: 2 callbacks suppressed
Jan 24 12:01:07 localhost kernel: Buffer I/O error on dev sr0, logical block 177075, async page read
Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#13 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#13 Sense Key : Illegal Request [current] 
Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#13 Add. Sense: Read of scrambled sector without authentication

As I described above, you don't have libdvdcss installed.  Therefore, the player software can't supply the optical drive with the decryption keys needed to allow it to read the disk.

Installing libdvdcss should fix you up.

You will get nowhere trying to convince MGA to install this by default.  It's illegal in some places (like the USA), but legal in others (like France).  So MGA can get away with including the packages in tainted and telling people that if they choose to install them it's their own lookout as to whether it's legal for them to do it, but to install them by default would make the distro illegal in places that don't allow it.

(In reply to Frank Griffin from comment #10)
> (In reply to Marja van Waes from comment #4)
> > (User marja isn't a member of the cdrom group, but I had no problem starting
> > "Murder on the Orient Express" from DVD just now.)
> 
> Interesting, because on my cauldron the optical drive devices are defined as:
> 
> [root@ftglap ~]# ls -l /dev/sr*
> brw-rw----+ 1 root cdrom 11, 0 Jan 21 15:46 /dev/sr0
> 
> so if you're not root or in cdrom, you should be denied.

There's an + at the end of  brw-rw----+ ... iinm, that means that an ACL is set, doesn't it?

Even if that's not what it means, it is certainly handled by an ACL:

  [marja@localhost ~]$ getfacl /dev/sr0
  getfacl: Removing leading '/' from absolute path names
  # file: dev/sr0
  # owner: root
  # group: cdrom
  user::rw-
  user:marja:rw-
  group::rw-
  mask::rw-
  other::---

  [marja@localhost ~]$

In the ACL I have "rw-", so it works for me despite not being a member of the cdrom group.

(In reply to Frank Griffin from comment #11)
> OK, I should have looked at the attachment:
> 
> Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 FAILED Result:
> hostbyte=DID_OK driverbyte=DRIVER_SENSE
> Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 Sense Key :
> Illegal Request [current] 
> Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 Add. Sense: Read
> of scrambled sector without authentication
> Jan 24 12:01:07 localhost kernel: sr 3:0:0:0: [sr0] tag#12 CDB: Read(10) 28
> 00 00 02 b3 b3 00 00 01 00
.....

And I should have had a better look, I had missed that part.

(Apart from that, my test DVD was from 1999.... maybe there's nothing to be decrypted on its :-/ )

You're right, Marja, I see that here as well.  But I confess I've never understood the use of ACLs for stuff like this.  If you're going to give every logged-on user permissions to optical devices, why even have a cdrom group or why not just automatically enroll every created user in that group ?  Or just give ----rw access to "other" ?

Created attachment 8895 [details]
vlc same error - unable to play DVD -

Tried several different DVD's (latest try is one from 2000).

So, set up the permission and I rebooted per your suggestion.  Still having errors.

hope journal helps.

(In reply to Marja van Waes from comment #13)
> (Apart from that, my test DVD was from 1999.... maybe there's nothing to be
> decrypted on its :-/ )

No, the dvdcss encryption scheme goes back to the ark.  Unless your DVD was created from a personal camera or some such.  If it's commercial, it's encrypted, unless you used some rumoured Chinese software ( :-P ) to create an unencrypted ISO from it.

(In reply to Frank Griffin from comment #14)
> You're right, Marja, I see that here as well.  But I confess I've never
> understood the use of ACLs for stuff like this.  If you're going to give
> every logged-on user permissions to optical devices, why even have a cdrom
> group or why not just automatically enroll every created user in that group
> ?  Or just give ----rw access to "other" ?

Learning about ACLs is on my todo list since many years. Tbh, all I know is that many sysadmins love them. The rest is a still mystery ;-)

Brian, install libdvdcss from tainted if it is legal for you to do so.  Otherwise, you're out of luck unless you buy some player software which legally obtains the needed dvdcss keys.

(In reply to Frank Griffin from comment #16)
> (In reply to Marja van Waes from comment #13)
> > (Apart from that, my test DVD was from 1999.... maybe there's nothing to be
> > decrypted on its :-/ )
> 
> No, the dvdcss encryption scheme goes back to the ark.  Unless your DVD was
> created from a personal camera or some such.  If it's commercial, it's
> encrypted, unless you used some rumoured Chinese software ( :-P ) to create
> an unencrypted ISO from it.

It's commercial and I don't have tainted enabled, don't have libdvdcss

  [marja@localhost ~]$ rpm -qa | grep dvd
  lib64dvdread4-5.0.3-1.mga6
  dvdauthor-0.7.2-1.mga6
  dvd+rw-tools-7.1-11.mga6
  lib64dvdnav4-5.0.3-2.mga6
  [marja@localhost ~]$ 

So I'm just wondering why it works for me.

Maybe it's better to not even want to know, though :-þ

I think Frank found the issue.  Blocked by my location - U.S. and licensing

Sorry about the rabbit trail.  I didn't think I ran into that before.

(In reply to Brian Rockwell from comment #20)
> I think Frank found the issue.  Blocked by my location - U.S. and licensing
> 
> Sorry about the rabbit trail.  I didn't think I ran into that before.

No problem, I learned a lot from it.

I think it works for me because I tried a Region 2 DVD.

France is region 2, too, and Frank said:

(In reply to Frank Griffin from comment #11)

> 
> Installing libdvdcss should fix you up.
> 
> You will get nowhere trying to convince MGA to install this by default. 
> It's illegal in some places (like the USA), but legal in others (like
> France). 

Maybe, if you live in Europe, something is installed by default that provides something similar to libdvdcss, but only for Region 2 ?

@ Brian

Does the tainted package work for you, or won't you try?

(In reply to Marja van Waes from comment #21)
> (In reply to Brian Rockwell from comment #20)
> > I think Frank found the issue.  Blocked by my location - U.S. and licensing
> > 

> 
> @ Brian
> 
> Does the tainted package work for you, or won't you try?

Forget that, I should have read what your location is. You can't try!

Closing.

Status: NEW => RESOLVED
Resolution: (none) => INVALID

(In reply to Marja van Waes from comment #21)
> Maybe, if you live in Europe, something is installed by default that
> provides something similar to libdvdcss, but only for Region 2 ?
> 
> @ Brian
> 
> Does the tainted package work for you, or won't you try?

No, you either install it or you don't.  I don't think anything in the install can detect what your region is, and that isn't really the issue anyway.  The issue is whether it's legal in your locality to use libdvdcss to subvert DVD encryption or not, and I don't think that anyone/anything tracks that.  You either decide that it's legal for you and use it, or you decide that you don't care whether it's legal or not, and use it anyway.  libdvdcss has been in the wild for many years now, and the community consensus is that there is virtually no probability that this particular genie will ever be put back into the bottle.  They tried to use a new security algorithm for BlueRay, but it was cracked within a month, and the status there is pretty much the same.