Gentoo Samba3/CUPS/Clam AV HOWTO

1. Introduction to this HOWTO

Purpose 

This HOWTO is designed to help you move a network from many different clients speaking different languages, to many different machines that speak a common language. The ultimate goal is to help differing architectures and technologies, come together in a productive, happily coexisting environment.

Following the directions outlined in this HOWTO should give you an excellent step towards a peaceful cohabitation between Windows, and virtually all known variations of *nix.

This HOWTO originally started not as a HOWTO, but as a FAQ. It was intended to explore the functionality and power of the Gentoo system, portage and the flexibility of USE flags. Like so many other projects, it was quickly discovered what was missing in the Gentoo realm: there weren't any Samba HOWTO's catered for Gentoo users. These users are more demanding than most; they require performance, flexibility and customization. This does not however imply that this HOWTO was not intended for other distributions; rather that it was designed to work with a highly customized version of Samba.

This HOWTO will describe how to share files and printers between Windows PCs and *nix PCs. It will also demonstrate the use of the VFS (Virtual File System) feature of Samba to incorporate automatic virus protection. As a finale, it will show you how to mount and manipulate shares.

There are a few topics that will be mentioned, but are out of the scope of this HOWTO. These will be noted as they are presented.

This HOWTO is based on a compilation and merge of an excellent HOWTO provided in the Gentoo forums by Andreas "daff" Ntaflos and the collected knowledge of Joshua Preston. The link to this discussion is provided below for your reference:

• HOWTO CUPS+Samba: printing from Windows & Linux

Before you use this guide 

There are a several other guides for setting up CUPS and/or Samba, please read them as well, as they may tell you things left out of this HOWTO (intentional or otherwise). One such document is the very useful and well written Gentoo Printing Guide, as configuration issues and specific printer setup is not discussed here.

Brief Overview 

After presenting the various USE flags, the following list will outline all of the topics covered as they are presented:

• On the Samba server:
  • Install and configure CLAM-AV
  • Install and configure Samba
  • Install and configure CUPS
  • Adding the printer to CUPS
  • Adding the PS drivers for the Windows clients
• On the Unix clients:
  • Install and configure CUPS
  • Configuring a default printer
  • Mounting a Windows or Samba share
• On the Windows Clients:
  • Configuring the printer
  • Accessing Samba shares

Requirements 

We will need the following:

• net-fs/samba
• app-antivirus/clamav
• net-print/cups
• net-print/foomatic
• net-print/hpijs (if you have an HP printer)
• A kernel of sorts (preferably 2.4.24+ or 2.6.x)
• A printer (PS or non-PS, maybe not TOO new or fancy)
• A working network (home/office/etc) consisting of more than one machine)

The main package we use here is net-fs/samba, however, you will need a kernel with smbfs support enabled in order to mount a samba or windows share from another computer. CUPS will be emerged if it is not already. app-antivirus/clamav will be used also, but others should be easily adapted to work with Samba.

2. Getting acquainted with Samba

The USE Flags 

Before emerging anything, take a look at the various USE flags available to Samba.

kerberos mysql xml acl cups ldap pam readline python oav

Depending on the network topology and the specific requirements of the server, the USE flags outlined below will define what to include or exclude from the emerging of Samba.

A couple of things worth mentioning about the USE flags and different Samba functions include:

• ACLs on ext2/3 are implemented through extended attributes (EAs). EA and ACL kernel options for ext2 and/or ext3 will need to be enabled (depending on which file system is being used - both can be enabled).
• While Active Directory, ACL, and PDC functions are out of the intended scope of this HOWTO, you may find these links as helpful to your cause:
  • http://www.bluelightning.org/linux/samba_acl_howto/
  • http://open-projects.linuxcare.com/research-papers/winbind-08162000.html
  • http://www.wlug.org.nz/HowtoSamba3AndActiveDirectory

3. Server Software Installation

Emerging Samba 

First of all: be sure that all your hostnames resolve correctly. Either have a working domain name system running on your network or appropriate entries in your /etc/hosts file. cupsaddsmb often borks if hostnames don't point to the correct machines.

Hopefully now you can make an assessment of what you'll actually need in order to use Samba with your particular setup. The setup used for this HOWTO is:

• oav
• cups
• readline
• pam

To optimize performance, size and the time of the build, the USE flags are specifically included or excluded.

(Note the USE flags!)
# USE="oav readline cups pam -python -ldap -kerberos -xml -acl -mysql" emerge net-fs/samba

This will emerge Samba and CUPS (if CUPS is not already emerged).

Emerging Clam AV 

Because the oav USE flag only provides an interface to allow on access virus scanning, the actual virus scanner must be emerged. The scanner used in this HOWTO is Clam AV.

# emerge app-antivirus/clamav

Emerging foomatic 

# emerge net-print/foomatic

Emerging net-print/hpijs 

You only need to emerge this if you use an HP printer.

# emerge net-print/hpijs

4. Server Configuration

Configuring Samba 

The main Samba configuration file is /etc/samba/smb.conf. It is divided in sections indicated by [sectionname]. Comments are either # or ;. A sample smb.conf is included below with comments and suggestions for modifications. If more details are required, see the man page for smb.conf, the installed smb.conf.example, the Samba Web site or any of the numerous Samba books available.

[global]
# Replace MYWORKGROUPNAME with your workgroup/domain
workgroup = MYWORKGROUPNAME
# Of course this has no REAL purpose other than letting
# everyone know its not Windows!
# %v prints the version of Samba we are using.
server string = Samba Server %v
# We are going to use cups, so we are going to put it in here ;-)
printcap name = cups
printing = cups
load printers = yes
# We want a log file and we do not want it to get bigger than 50kb.
log file = /var/log/samba/log.%m
max log size = 50
# We are going to set some options for our interfaces...
socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
# This is a good idea, what we are doing is binding the
# samba server to our local network.
# For example, if eth0 is our local network device
interfaces = lo eth0
bind interfaces only = yes
# Now we are going to specify who we allow, we are afterall
# very security conscience, since this configuration does
# not use passwords!
hosts allow = 127.0.0.1 192.168.1.0/24
hosts deny = 0.0.0.0/0
# Other options for this are USER, DOMAIN, ADS, and SERVER
# The default is user
security = share
# No passwords, so we're going to use a guest account!
guest account = samba
guest ok = yes
# We now will implement the on access virus scanner.
# NOTE: By putting this in our [Global] section, we enable
# scanning of ALL shares, you could optionally move
# these to a specific share and only scan it.

# For Samba 3.x
vfs object = vscan-clamav
vscan-clamav: config-file = /etc/samba/vscan-clamav.conf

# For Samba 2.2.x
vfs object = /usr/lib/samba/vfs/vscan-clamav.so
vfs options = config-file = /etc/samba/vscan-clamav.conf

# Now we setup our print drivers information!
[print$]
comment = Printer Drivers
path = /etc/samba/printer # this path holds the driver structure
guest ok = yes
browseable = yes
read only = yes
# Modify this to "username,root" if you don't want root to
# be the only printer admin)
write list = root

# Now we'll setup a printer to share, while the name is arbitrary
# it should be consistent throughout Samba and CUPS!
[HPDeskJet930C]
comment = HP DeskJet 930C Network Printer
printable = yes
path = /var/spool/samba
public = yes
guest ok = yes
# Modify this to "username,root" if you don't want root to
# be the only printer admin)
printer admin = root

# Now we setup our printers share.  This should be
# browseable, printable, public.
[printers]   
comment = All Printers
browseable = no 
printable = yes   
writable = no
public = yes   
guest ok = yes
path = /var/spool/samba
# Modify this to "username,root" if you don't want root to
# be the only printer admin)
printer admin = root

# We create a new share that we can read/write to from anywhere
# This is kind of like a public temp share, anyone can do what
# they want here.
[public]
comment = Public Files
browseable = yes
public = yes
create mode = 0766
guest ok = yes
path = /home/samba/public

Now create the directories required for the minimum configuration of Samba to share the installed printer throughout the network.

# mkdir /etc/samba/printer
# mkdir /var/spool/samba
# mkdir /home/samba/public

At least one Samba user is required in order to install the printer drivers and to allow users to connect to the printer. Users must exist in the system's /etc/passwd file.

# smbpasswd -a root 

(If another user is to be a printer admin)
# smbpasswd -a username

The Samba passwords need not be the same as the system passwords in /etc/passwd.

You will also need to update /etc/nsswitch.conf so that Windows systems can be found easily using NetBIOS:

# nano -w /etc/nsswitch.conf
(Edit the hosts: line)
hosts: files dns wins

Configuring Clam AV 

The configuration file specified to be used in smb.conf is /etc/samba/vscan-clamav.conf. While these options are set to the defaults, the infected file action may need to be changed.

[samba-vscan]
; run-time configuration for vscan-samba using
; clamd
; all options are set to default values

; do not scan files larger than X bytes. If set to 0 (default),
; this feature is disable (i.e. all files are scanned)
max file size = 0

; log all file access (yes/no). If set to yes, every access will
; be logged. If set to no (default), only access to infected files
; will be logged
verbose file logging = no

; if set to yes (default), a file will be scanned while opening
scan on open = yes
; if set to yes, a file will be scanned while closing (default is yes)
scan on close = yes

; if communication to clamd fails, should access to file denied?
; (default: yes)
deny access on error = yes

; if daemon fails with a minor error (corruption, etc.),
; should access to file denied?
; (default: yes)
deny access on minor error = yes

; send a warning message via Windows Messenger service
; when virus is found?
; (default: yes)
send warning message = yes

; what to do with an infected file
; quarantine: try to move to quantine directory; delete it if moving fails
; delete:     delete infected file
; nothing:    do nothing
infected file action = delete

; where to put infected files - you really want to change this!
; it has to be on the same physical device as the share!
quarantine directory  = /tmp
; prefix for files in quarantine
quarantine prefix = vir-

; as Windows tries to open a file multiple time in a (very) short time
; of period, samba-vscan use a last recently used file mechanism to avoid
; multiple scans of a file. This setting specified the maximum number of
; elements of the last recently used file list. (default: 100)
max lru files entries = 100

; an entry is invalidated after lru file entry lifetime (in seconds).
; (Default: 5)
lru file entry lifetime = 5

; socket name of clamd (default: /var/run/clamd)
clamd socket name = /var/run/clamd

It is generally a good idea to start the virus scanner immediately. Add it to the default runlevel and then start the clamd service immediately.

# rc-update add clamd default
# /etc/init.d/clamd start

Configuring CUPS 

This is a little more complicated. CUPS' main config file is /etc/cups/cupsd.conf. It's structure is similar to Apache's httpd.conf file, so many you may find it familiar. Outlined in the example are the directives that need to be changed:

ServerName PrintServer          # your printserver name
ServerAdmin root@PrintServer    # the person for printer-related hate-mail, eg you

AccessLog /var/log/cups/access_log # probably doesn't need changing
ErrorLog  /var/log/cups/error_log  # doesn't really need changing either

LogLevel  debug # only while isntalling and testing, should later be 
		# changed to 'info'

MaxClients 100 # I've had to set this to 1000000000 or so because some time back,
               # there seemed to be a bug in CUPS' controlling of the web interface,
               # making CUPS think a denial of service attack was in progress when
               # I tried to configure a printer with the web interface. weird.

BrowseAddress @IF(eth0) # Change this to your internal net interface 

<Location />
Order Deny,Allow
Deny From All
Allow From 192.168.1.*  # the addresses of your internel network
                        # eg 192.168.1.* will allow connections from any host on
                        # the 192.168.1.0 network. change to whatever suits you
</Location>

<Location /admin>
AuthType Basic
AuthClass System
Allow From 192.168.1.*  # same as above, allow any host on the
                        # 192.168.1.0 network to connect and do 
                        # administrative tasks after authenticating
Order Deny,Allow
Deny From All
</Location>

Edit /etc/cups/mime.convs to uncomment some lines. The changes to mime.convs and mime.types are needed to make CUPS print Microsoft Office document files.

(The following line is found near the end of the file. Uncomment it)
application/octet-stream        application/vnd.cups-raw        0       

Edit /etc/cups/mime.convs to uncomment some lines.

(The following line is found near the end of the file. Uncomment it)
application/octet-stream 

CUPS needs to be started on boot, and started immediately.

(To start CUPS on boot)
# rc-update add cupsd default
(To start CUPS if it isn't started)
# /etc/init.d/cupsd start
(If CUPS is already started we'll need to restart it!)
# /etc/init.d/cupsd restart

Installing a printer for and with CUPS 

First, go to LinuxPrinting.Org to find and download the correct PPD file for your printer and CUPS. To do so, click the link Printer Listings to the left. Select your printers manufacturer and the model in the pulldown menu, eg HP and DeskJet 930C. Click "Show". On the page coming up click the "recommended driver" link after reading the various notes and information. Then fetch the PPD file from the next page, again after reading the notes and introductions there. You may have to select your printers manufacturer and model again. Reading the CUPS quickstart guide is also very helpful when working with CUPS.

Now you have a PPD file for your printer to work with CUPS. Place it in /usr/share/cups/model. The PPD for the HP DeskJet 930C was named HP-DeskJet_930C-hpijs.ppd. You should now install the printer. This can be done via the CUPS web interface or via command line. The web interface is found at http://PrintServer:631 once CUPS is running.

# lpadmin -p HPDeskJet930C -E -v usb:/dev/ultp0 -m HP-DeskJet_930C-hpijs.ppd

Remember to adjust to what you have. Be sure to have the name (-p argument) right (the name you set above during the Samba configuration!) and to put in the correct usb:/dev/usb/blah, parallel:/dev/blah or whatever device you are using for your printer.

You should now be able to access the printer from the web interface and be able to print a test page.

Installing the Windows printer drivers 

Now that the printer should be working it is time to install the drivers for the Windows clients to work. Samba 2.2 introduced this functionality. Browsing to the print server in the Network Neighbourhood, right-clicking on the printershare and selecting "connect" downloads the appropriate drivers automagically to the connecting client, avoiding the hassle of manually installing printer drivers locally.

There are two sets of printer drivers for this. First, the Adobe PS drivers which can be obtained from Adobe (PostScript printer drivers). Second, there are the CUPS PS drivers, to be obtained from the CUPS homepage and selecting "CUPS Driver for Windows" from the pull down menu. There doesn't seem to be a difference between the functionality of the two, but the Adobe PS drivers need to be extracted on a Windows System since it's a Windows binary. Also the whole procedure of finding and copying the correct files is a bit more hassle. The CUPS drivers seem to support some options the Adobe drivers don't.

This HOWTO uses the CUPS drivers for Windows. The downloaded file is called cups-samba-5.0rc2.tar.gz. Extract the files contained into a directory.

# tar -xzf cups-samba-5.0rc2.tar.gz
# cd cups-samba-5.0rc2
(Only use this script if CUPS resides in /usr/share/cups)
# ./cups-samba.install

cups-samba.ss is a TAR archive containing three files: cups5.hlp, cupsdrvr5.dll and cupsui5.dll. These are the actual driver files.

Suppose your CUPS installation resides under /usr/local/share/cups/, and you want to install the drivers there. Do the following:

# cd /path/you/extracted/the/CUPS-driver/tarball/into
# tar -xf cups-samba.ss
(This extracts the files to usr/share/cups/drivers under the CURRENT WORKING DIRECTORY)
# cd usr/share/cups/drivers
(no leading / !)
# cp cups* /usr/local/share/cups/drivers

Now we'll use the script cupsaddsmb provided by the CUPS distribution. It's man page is an interesting read.

# cupsaddsmb -H PrintServer -U root -h PrintServer -v HPDeskJet930C
(Instead of HPDeskJet930C you could also specify "-a", which will
"export all known printers".)
# cupsaddsmb -H PrintServer -U root -h PrintServer -a

Here are common errors that may happen:

• The hostname given as a parameter for -h and -H (PrintServer) often does not resolve correctly and doesn't identify the print server for CUPS/Samba interaction. If an error like: Warning: No PPD file for printer "CUPS_PRINTER_NAME" - skipping! occurs, the first thing you should do is substitute PrintServer with localhost and try it again.
• The command fails with an NT_STATUS_UNSUCCESSFUL. This error message is quite common, but can be triggered by many problems. It's unfortunately not very helpful. One thing to try is to temporarily set security = user in your smb.conf. After/if the installation completes successfully, you should set it back to share, or whatever it was set to before.

This should install the correct driver directory structure under /etc/samba/printer. That would be /etc/samba/printer/W32X86/2/. The files contained should be the 3 driver files and the PPD file, renamed to YourPrinterName.ppd (the name which you gave the printer when installing it (see above).

Pending no errors or other complications, your drivers are now installed.

Finalizing our setup 

Lastly, setup our directories.

# mkdir /home/samba
# mkdir /home/samba/public
# chmod 755 /home/samba
# chmod 755 /home/samba/public

Testing our Samba configuration 

We will want to test our configuration file to ensure that it is formatted properly and all of our options have at least the correct syntax. To do this we run testparm.

(By default, testparm checks /etc/samba/smb.conf)
# /usr/bin/testparm
Load smb config files from /etc/samba/smb.conf
Processing section "[printers]"
Global parameter guest account found in service section!
Processing section "[public]"
Global parameter guest account found in service section!
Loaded services file OK.
Server role: ROLE_STANDALONE
Press enter to see a dump of your service definitions
 ...
 ...

Starting the Samba service 

Now configure Samba to start at bootup; then go ahead and start it.

# rc-update add samba default
# /etc/init.d/samba start

Checking our services 

It would probably be prudent to check our logs at this time also. We will also want to take a peak at our Samba shares using smbclient.

# smbclient -L localhost
Password:
(You should see a BIG list of services here.)

5. Configuration of the Clients

Printer configuration of *nix based clients 

Despite the variation or distribution, the only thing needed is CUPS. Do the equivalent on any other UNIX/Linux/BSD client.

# emerge cups
# nano -w /etc/cups/client.conf
ServerName PrintServer      # your printserver name

That should be it. Nothing else will be needed.

If you use only one printer, it will be your default printer. If your print server manages several printers, your administrator will have defined a default printer on the server. If you want to define a different default printer for yourself, use the lpoptions command.

(List available printers)
# lpstat -a
(Sample output, yours will differ)
HPDeskJet930C accepting requests since Jan 01 00:00
laser accepting requests since Jan 01 00:00
(Define HPDeskJet930C as your default printer)
# lpoptions -d HPDeskJet930C

(Specify the printer to be used)
# lp -d HPDeskJet930C anything.txt
(Use your default printer)
# lp foobar.whatever.ps

Just point your web browser to http://printserver:631 on the client if you want to manage your printers and their jobs with a nice web interface. Replace printserver with the name of the machine that acts as your print server, not the name you gave to the cups print server if you used different names.

Mounting a Windows or Samba share in GNU/Linux 

Now is time to configure our kernel to support smbfs. Since I'm assumming we've all compiled at least one kernel, we'll need to make sure we have all the right options selected in our kernel. For simplicity sake, make it a module for ease of use. It is the author's opinion that kernel modules are a good thing and should be used whenever possible.

CONFIG_SMB_FS=m
CONFIG_SMB_UNIX=y

Then make the module/install it; insert them with:

# modprobe smbfs

Once the modules is loaded, mounting a Windows or Samba share is possible. Use mount to accomplish this, as detailed below:

(The syntax for mounting a Windows/Samba share is:
  mount -t smbfs [-o username=xxx,password=xxx] //server/share /mnt/point
If we are not using passwords or a password is not needed)

# mount -t smbfs //PrintServer/public /mnt/public

(If a password is needed)
# mount -t smbfs -o username=USERNAME,password=PASSWORD //PrintServer/public /mnt/public

After you mount the share, you would access it as if it were a local drive.

Printer Configuration for Windows NT/2000/XP clients 

That's just a bit of point-and-click. Browse to \\PrintServer and right click on the printer (HPDeskJet930C) and click connect. This will download the drivers to the Windows client and now every application (such as Word or Acrobat) will offer HPDeskJet930C as an available printer to print to. :-)

6. Final Notes

A Fond Farewell 

Well that should be it. You should now have a successful printing enviroment that is friendly to both Windows and *nix as well as a fully virus-free working share!

7. Links and Resources

Links 

These are some links that may help you in setting up, configuration and troubleshooting your installation:

• CUPS Homepage
• Samba Homepage
• LinuxPrinting dot Org
• Kurt Pfeifle's Samba Print HOWTO ( This HOWTO really covers ANYTHING and EVERYTHING I've written here, plus a LOT more concerning CUPS and Samba, and generally printing support on networks. A really interesting read, with lots and lots of details)
• FreeBSD Diary's CUPS Topic

Troubleshooting 

See this page from Kurt Pfeifle's "Printing Support in Samba 3.0" manual. Lots of useful tips there! Be sure to look this one up first, before posting questions and problems! Maybe the solution you're looking for is right there.