[linux-cifs-client] Question on current state of sec=krb5* integration in cifs.ko

[Jeff Layton]

On Fri, 23 Oct 2009 15:54:29 +0200
Holger Rauch <holger.rauch at empic.de> wrote:

> Hi Jeff,
> 
> first of all, thanks for your quick reply.
> 
> On Fri, 23 Oct 2009, Jeff Layton wrote:
> 
> > On Fri, 23 Oct 2009 13:12:14 +0200
> > Holger Rauch <holger.rauch at empic.de> wrote:
> > > [...] 
> > > I just tried that. Mount options in /etc/fstab are
> > > 
> > > noauto,sec=krb5i,iocharset=iso8859-15
> > > 
> > > When I issue the mount cmd, it asks me for a password.
> > 
> > That probably means that you have a fairly old mount.cifs program. The
> > more recent ones don't prompt for a password when sec=krb5* is
> > specified. Try adding the "guest" option which will disable password
> > prompting.
> 
> Ok, I tried that (debugging output included as well; interestingly
> enough, "mount.cifs -V" only outputs the help message, even if
> mount.cifs is called with an absolute path). This happenend on a
> Debian Lenny system having the shipped kernel version (uname -r):
> 
> 2.6.26-2-686-bigmem
> 
> Since "mount.cifs -V" didn't come up with version info, I used
> "apt-cache show smbfs" ("smbfs" is the Debian package mount.cifs is
> contained in). It has the same version as the other Samba packages
> shipped with Debian: 3.2.5
> 
> ==============
> 
> pia:~# mount -t cifs //server/myuser
> /cifs/user --verbose -o
> sec=krb5i,user=myuser,guest,iocharset=iso8859-15
> parsing options: rw,sec=krb5i,user=myuser,guest,iocharset=iso8859-15
> 
> mount.cifs kernel mount options
> unc=//server\myuser,ip=ww.xx.yy.zz,ver=1,rw,sec=krb5i,user=myuser,guest,iocharset=iso8859-15
> 
> mount error 95 = Operation not supported
> Refer to the mount.cifs(8) manual page (e.g.man mount.cifs)
> pia:~# dmesg
> [8046556.840192]  fs/cifs/cifsfs.c: Devname:
> //prag-old.er.heitec.net/hrauch flags: 64 
> [8046556.847954]  fs/cifs/connect.c: CIFS VFS: in cifs_mount as Xid:
> 15 with uid: 0
> [8046556.895920]  fs/cifs/connect.c: iocharset set to iso8859-15
> [8046556.903932]  fs/cifs/connect.c: Username: myuser
> [8046556.911928]  fs/cifs/connect.c: UNC:
> \\server\myuser ip: ww.xx.yy.zz
> [8046556.916743]  fs/cifs/connect.c: Socket created
> [8046556.924050]  fs/cifs/connect.c: sndbuf 16384 rcvbuf 87380
> rcvtimeo 0x7fffffff
> [8046556.935312]  fs/cifs/connect.c: Existing smb sess not found
> [8046556.935312]  fs/cifs/connect.c: Demultiplex PID: 6171
> [8046556.946262]  fs/cifs/cifssmb.c: secFlags 0x1009
> [8046556.950328]  fs/cifs/cifssmb.c: Kerberos only mechanism, enable
> extended security
> [8046556.957962]  fs/cifs/transport.c: For smb_command 114
> [8046556.962692]  fs/cifs/transport.c: Sending smb of length 78
> [8046556.968883]  fs/cifs/connect.c: rfc1002 length 0xbe
> [8046556.974665]  fs/cifs/cifssmb.c: Dialect: 2
> [8046556.978940]  fs/cifs/asn1.c: OID len = 7 oid = 0x1 0x2 0x348
> 0x1bb92
> [8046556.989230]  fs/cifs/asn1.c: OID len = 7 oid = 0x1 0x2 0x348 0xbb92
> [8046556.991772]  fs/cifs/asn1.c: OID len = 10 oid = 0x1 0x3 0x6 0x1
> [8046556.998296]  fs/cifs/asn1.c: Need to call asn1_octets_decode()
> function for cifs/server at MYREALM
> [8046557.008389]  fs/cifs/cifssmb.c: Must sign - secFlags 0x1009
> [8046557.015170]  CIFS VFS: signing required but server lacks support


I think this message explains the problem ^^^^

You've request krb5i, but your server doesn't support signing. You
might want to try sec=krb5 and see if that works.

> [8046557.022305]  fs/cifs/cifssmb.c: negprot rc -95
> [8046557.136096]  fs/cifs/connect.c: No session or bad tcon
> [8046557.213439]  fs/cifs/connect.c: CIFS VFS: leaving cifs_mount (xid
> = 15) rc = -95
> [8046557.221012]  CIFS VFS: cifs_mount failed w/return code = -95
> 
> ==============
> 
> Do I need a more recent kernel? If so, which one would you recommend?
> 
> Thanks in advance for any hints & kind regards,
> 
>        Holger
>        


-- 
Jeff Layton <jlayton at redhat.com>