Man Linux: Main Page and Category List

NAME

       saned - SANE network daemon

SYNOPSIS

       saned [ -a [ username ] | -d [ n ] | -s [ n ] ]

DESCRIPTION

       saned  is  the SANE (Scanner Access Now Easy) daemon that allows remote
       clients to access image acquisition  devices  available  on  the  local
       host.

OPTIONS

       The  -a flag requests that saned run in standalone daemon mode. In this
       mode, saned will detach from the console and  run  in  the  background,
       listening  for  incoming  client connections; inetd is not required for
       saned operations in this mode. If the optional username is given  after
       -a  , saned will drop root privileges and run as this user (and group).

       The -d and -s flags request that saned run in debug mode (as opposed to
       inetd(8)  mode).  In this mode, saned explicitly waits for a connection
       request.  When compiled with debugging  enabled,  these  flags  may  be
       followed  by a number to request debug info. The larger the number, the
       more verbose the debug output.  E.g., -d128 will  request  printing  of
       all debug info. Debug level 0 means no debug output at all. The default
       value is 2. If flag -d is used, the debug messages will be  printed  to
       stderr while -s requests using syslog.

       If saned is run from inetd or xinetd, no option can be given.

CONFIGURATION

       First and foremost: saned is not intended to be exposed to the internet
       or other non-trusted networks. Make sure  that  access  is  limited  by
       tcpwrappers  and/or  a firewall setup. Don’t depend only on saned’s own
       authentication. Don’t run saned as root if it’s not necessary.  And  do
       not install saned as setuid root.

       The  saned.conf configuration file contains both options for the daemon
       and the access list.

       data_portrange = min_port - max_port
              Specify the port range to use for the data  connection.  Pick  a
              port  range  between 1024 and 65535; don’t pick a too large port
              range, as it may have performance issues.  Use  this  option  if
              your saned server is sitting behind a firewall. If that firewall
              is a Linux machine, we strongly recommend  using  the  Netfilter
              nf_conntrack_sane module instead.

       The  access  list  is  a list of host names, IP addresses or IP subnets
       (CIDR notation) that are permitted to  use  local  SANE  devices.  IPv6
       addresses  must be enclosed in brackets, and should always be specified
       in  their  compressed  form.  Connections  from  localhost  are  always
       permitted.  Empty  lines  and  lines  starting with a hash mark (#) are
       ignored. A line containing the single character ‘‘+’’ is interpreted to
       match  any hostname. This allows any remote machine to use your scanner
       and may present a security risk, so this shouldn’t be used  unless  you
       know what you’re doing.

       A sample configuration file is shown below:

              # Daemon options
              data_portrange = 10000 - 10100
              # Access list
              scan-client.somedomain.firm
              # this is a comment
              192.168.0.1
              192.168.2.12/29
              [::1]
              [2001:7a8:185e::42:12]/64

       The  case of the host names does not matter, so AHost.COM is considered
       identical to ahost.com.

INETD CONFIGURATION

       For saned to work properly in its default mode of operation, it is also
       necessary  to  add  a configuration line to /etc/inetd.conf.  Note that
       your inetd must support IPv6 if you want to connect to saned over  IPv6
       ;  xinetd  and  openbsd-inetd  are  known  to  support  IPv6, check the
       documentation for your inetd daemon.

       The configuration line normally looks like this:

              sane-port stream tcp nowait saned.saned /usr/sbin/saned saned

       However, if your system uses tcpd(8) for additional security screening,
       you  may  want  to  disable  saned  access  control by putting ‘‘+’’ in
       saned.conf and use a line of  the  following  form  in  /etc/inetd.conf
       instead:

              sane-port   stream   tcp   nowait   saned.saned   /usr/sbin/tcpd
              /usr/sbin/saned

       Note that both examples assume that there is a saned group and a  saned
       user.   If  you  follow  this example, please make sure that the access
       permissions on the special device are set such that  saned  can  access
       the  scanner  (the  program  generally  needs  read and write access to
       scanner devices).

       If xinetd is installed on your system instead of  inetd  the  following
       example for xinetd.conf may be helpful:

              # default: off
              # description: The sane server accepts requests
              # for network access to a local scanner via the
              # network.
              service sane-port
              {
                 port        = 6566
                 socket_type = stream
                 wait        = no
                 user        = saned
                 group       = saned
                 server      = /usr/sbin/saned
              }

       Finally,  it  is  also necessary to add a line of the following form to
       /etc/services:

              sane-port 6566/tcp # SANE network scanner daemon

       The official IANA short name for port 6566 is  "sane-port".  The  older
       name "sane" is now deprecated.

FILES

       /etc/hosts.equiv
              The  hosts listed in this file are permitted to access all local
              SANE devices.  Caveat: this file imposes serious security  risks
              and its use is not recommended.

       /etc/sane.d/saned.conf
              Contains  a list of hosts permitted to access local SANE devices
              (see also description of SANE_CONFIG_DIR below).

       /etc/sane.d/saned.users
              If this file contains lines of the form

              user:password:backend

              access to the listed backends is restricted. A  backend  may  be
              listed  multiple times for different user/password combinations.
              The server uses MD5 hashing if supported by the client.

ENVIRONMENT

       SANE_CONFIG_DIR
              This environment variable specifies the list of directories that
              may contain the configuration file.  Under UNIX, the directories
              are separated by a colon (‘:’), under OS/2, they  are  separated
              by  a  semi-colon  (‘;’).   If  this  variable  is  not set, the
              configuration file  is  searched  in  two  default  directories:
              first,   the   current  working  directory  (".")  and  then  in
              /etc/sane.d.  If the value of the environment variable ends with
              the  directory separator character, then the default directories
              are searched after the explicitly  specified  directories.   For
              example,  setting SANE_CONFIG_DIR to "/tmp/config:" would result
              in  directories  "tmp/config",  ".",  and  "/etc/sane.d"   being
              searched (in this order).

SEE ALSO

       sane(7),    scanimage(1),    xscanimage(1),    xcam(1),    sane-dll(5),
       sane-net(5), sane-"backendname"(5)
       http://www.penguin-breeder.org/?page=sane-net

AUTHOR

       David Mosberger

                                  20 Apr 2009                         saned(8)