saned(1) SANE Scanner Access Now Easy saned(1)NAMEsaned - SANE network daemon
SYNOPSISsaned [-d|-s [n]]
DESCRIPTIONsaned is the SANE (Scanner Access Now Easy) daemon that
allows remote clients to access image acquisition devices
available on the local host.
OPTIONS
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 authentification. Don't
run saned as root if it's not necessary. And do not
install saned as setuid root.
The contents of the saned.conf file is a list of host
names or IP addresses that are permitted to use local SANE
devices. 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:
scan-client.somedomain.firm
# this is a comment
192.168.0.1
::1
The case of the host names does not matter, so AHost.COM
is considered identical to ahost.com. IPv6 addresses
should always be specified in their compressed form.
For saned to work properly, 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 stream tcp nowait saned.saned
/usr/freeware/sbin/saned saned
However, if your system uses tcpd(8) for additional secu-
rity screening, you may want to disable saned access con-
trol by putting ``+'' in saned.conf and use a line of the
following form in /etc/inetd.conf instead:
sane stream tcp nowait saned.saned /usr/sbin/tcpd
/usr/freeware/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 = 6566
socket_type = stream
wait = no
user = saned
group = saned
server = /usr/freeware/sbin/saned
}
Finally, it is also necessary to add a line of the follow-
ing form to /etc/services:
sane 6566/tcp # SANE network scanner daemon
RESTRICTIONS
In addition to the control connection (port 6566) saned
also uses a data connection. The port of this socket is
selected by the operating system and can't be specified by
the user currently. This may be a problem if the connec-
tion must go through a firewall (packet filter).
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.
/usr/freeware/etc/sane.d/saned.conf
Contains a list of hosts permitted to access local
SANE devices (see also description of SANE_CON-
FIG_DIR below).
/usr/freeware/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
encryption 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 /usr/freeware/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 spec-
ified directories. For example, setting SANE_CON-
FIG_DIR to "/tmp/config:" would result in directo-
ries "tmp/config", ".", and "/usr/free-
ware/etc/sane.d" being searched (in this order).
SEE ALSOsane(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
sane-backends 1.0.12 9 Feb 2003 saned(1)