NAME
danted.conf - Dante server configuration file syntax
DESCRIPTION
The configuration file for the Dante server controls both access
controls and logging. It is divided into three parts; server settings,
rules, and routes. A line can be commented using the standard comment
character #.
SERVER SETTINGS
The server settings control the generic behaviour of the server. Each
keyword is separated from it's value by a ':' character.
compatibility
With the sameport keyword, the server attempts to use the same
port on the server and the client. This functionality is the
default, but when this option is given it will also be done with
privileged ports. The reuseaddr keyword might solve problems
when the bind extension is used but the effects of enabling
reuseaddr is currently unknown, do not enable it unless you
understand the effects.
connecttimeout
The number of seconds a client has to send the request after a
connect. Set it to 0 for forever.
external
The address to be used for outgoing connections. The address
given may be either a IP address or a interfacename. Can be
given multiple times for different addresses.
external.rotation
If more than one external address is given, this governs which
address is selected. Valid values are none (the default) and
route. The latter might require you to set user.privileged to
root.
Note that route might create problems for ftp-clients using
active ftp if the Dante bind extension is enabled for the ftp-
client.
internal
The internal addresses. Connections will only be accepted on
these addresses. The address given may be either a IP address
or a interfacename.
iotimeout
The number of seconds an established connection can be idle.
Set it to 0 for forever.
logoutput
This value controls where the server sends logoutput. It can be
either syslog[/facility], stdout, stderr, a filename, or a
combination.
method A list of acceptable authentication methods for socks-rules, in
order of preference. Supported values are username, none,
rfc931 and pam. This list is used as the default for all coming
rules until changed. Then the changed list is used as the
default for the next rules.
If a method is not set in this list it will never be selected.
See the section on methods for a explanation of the different
methods.
clientmethod
A list of acceptable authentication methods for client-rules, in
order of preference. These are the authenticationmethods that
can provide authentications based on just the client's TCP
connection. Supported values are none, rfc931 and pam. This
list is used as the default for all coming rules until changed.
Then the changed list is used as the default for the next rules.
The default value is none.
If a method is not set in this list it will never be selected.
srchost
With the nomismatch keyword, the server will not accept connects
from addresses having a mismatch between DNS address and
hostname. Default is to accept them. With the nounknown
keyword, the server will not accept connects from addresses
without a DNS record. Default is to accept them.
user.privileged
Username which will be used for doing privileged operations.
user.notprivileged
User which the server runs as most of the time.
user.libwrap
User used to execute libwrap commands.
MODULES
The following modules are supported by Dante. Modules are purchased
separately from Inferno Nettverk A/S. See the Dante homepage for more
information.
bandwidth
The bandwidth module gives you control over how much bandwidth
the Dante server uses on behalf of different clients.
redirect
The redirect module gives you control over what addresses the
server will use on behalf of the client and allows you to both
redirect client requests to a different addresses aswell as
control the range of addresses and ports to be used on behalf of
the client.
session
The session module gives you control over the number of sessions
that can be created by different socks users.
METHODS
The Dante server supports the following methods. Some installations of
Dante may support only a subset of these.
none The method requires no form of authentication.
username
The method requires the client to provide a username and
password. This must match the username and password given in
the system passwordfile.
rfc931 The method requires the client host to provide a rfc931
("ident") reply for the connecting client. The name given in
the reply must be present in the password database.
pam The method requires the available clientdata to match against
the pam database.
ADDRESSES
Each address field can consist of a IP address (and where meaningful, a
netmask, separated from the IP address by a '/' sign.), a hostname, or
a domainname (designated so by the leading '.'). Each address can be
followed by a optional port specifier.
RULES
There are two sets of rules and they work at different levels. Rules
prefixed with client are checked first and are used to see if the
client is allowed to connect to the Dante server. We will call them
"client-rules". It is especially important that these do not use
hostnames but only IP addresses, both for security and performance
reasons. These rules work at the TCP/IP level.
The other rules, which we will call "socks-rules" are a level higher
and are checked after the client connection has been accepted by the
client-rules. The socks-rules are used to evaluate the socks request
that the client sends. They thus work at the socks protocol level.
Both set of rules start with a pass/deny keyword (the client-rules have
"client" prefixed to the pass/deny keyword) which determines if
connections matching the rule are to pass or be blocked. Both set of
rules also specify a from/to address pair which gives the addresses the
rule will match.
In both contexts, from means the clients address.
In the client-rule context, to means the address the request is
accepted on, i.e. the address the Dante server listens on.
In the socks-rule context, to means the client's destination address,
as formulated in the client's proxy request.
In addition to the addresses there is a set of optional keywords which
can be given. There are two forms of keywords, conditions and actions.
For each rule, all conditions are checked and if they match the
request, the actions are executed.
The list of condition keywords is: from, to, command, method, protocol,
proxyprotocol, user.
The list of actions keywords is: bandwidth, libwrap, log and redirect.
The format and content of the rules is identical, but client-rules may
contain only a subset of the socks-rules. More concrete, they may not
contain any keywords related to the socks protocol.
The contents of a client-rule is:
from The rule applies to requests coming from the address given as
value.
to The rule applies to requests going to the address given as
value.
port Parameter to from, to and via. Accepts the keywords eq/=,
neq/!=, ge/>=, le/<=, gt/>, lt/< followed by a number. A
portrange can also be given as "port <start #> - <end #>", which
will match all port numbers within the range <start #> and <end
#>.
libwrap
The server will pass the line to libwrap for execution.
log Used to control logging. Accepted keywords are connect,
disconnect, data, error and iooperation.
user The server will only accept connections from users matching one
of the names given as value. If no user value is given,
everyone in the passwordfile will be matched. The rule must
also allow usernamebased methods.
method Require that the connection be "authenticated" using one of the
given methods.
pam.servicename
Which servicename to use when involving pam. Default is
"sockd".
The contents of a socks-rule is:
from The rule applies to requests coming from the address given as
value.
to The rule applies to requests going to or using the address given
as value. Note that the meaning of this address is affected by
command.
port Parameter to from, to and via. Accepts the keywords eq/=,
neq/!=, ge/>=, le/<=, gt/>, lt/< followed by a number. A
portrange can also be given as "port <start #> - <end #>", which
will match all port numbers within the range <start #> and <end
#>.
bandwidth
The clients matching this rule will all share this amount of
bandwidth.
command
The rule applies to the given commands. Valid commands are
bind, bindreply, connect, udpassociate and udpreply. Can be
used instead of, or to complement, protocol.
libwrap
The server will pass the line to libwrap for execution.
log Used to control logging. Accepted keywords are connect,
disconnect, data and iooperation.
method Require that the connection be established using one of the
given methods. method always refers to the source part of the
rule. Valid values are the same as in the global method line.
pam.servicename
What servicename to use when involving pam. Default is "sockd".
protocol
The rule applies to the given protocols. Valid values are tcp
and udp. It is recommended that the command form is used since
it provides more accuracy in defining rules.
proxyprotocol
The rule applies to requests using the given proxyprotocol.
Valid proxyprotocols are socks_v4 and socks_v5.
redirect
The source and/or destination can be redirected using the
redirect statement. The syntax of the statement is as follows:
redirect from: ADDRESS
redirect to: ADDRESS
The semantics of from and to vary according to command and
should be intuitive enough.
user The server will accept connections from users matching one of
the names given as value. If no user value is given, everyone
in the passwordfile will be matched. The rule must in this case
also allow usernamebased methods.
ROUTES
The routes are specified with a route keyword. Inside a pair of parens
({}) a set of keywords control the behavior of the route. See
dante.conf(5) for a description. This is used to perform so-called
"server-chaining", where one socks-server connects to another socks-
server futher upstream.
EXAMPLES
See the example directory in the distribution.
FILES
/etc/danted.conf Dante server configuration file.
/etc/passwd file used when checking username/passwords.
AUTHORS
For Inferno Nettverk A/S, Norway:
Michael Shuldman <michaels@inet.no>: Design and implementation.
Karl-Andre' Skevik <karls@inet.no>: Autoconf and porting.
SEE ALSO
danted(8), dante.conf(5), hosts_access(5)
Information about new releases and other related issues can be found on
the Dante WWW home page at http://www.inet.no/dante.
May 11, 2001