3.3.9 Inetd-Style Components

Inetd-style components are declared using mode inetd statement. The ‘component’ declaration must contain a ‘socket’ statement:

Config: component: socket url

Define a socket to listen on. Allowed values for url are:

inet[+proto]://ip:port

Listen on IPv4² address ip (may be given as a symbolic host name), on port port. Optional proto defines the protocol to use. It must be a valid protocol name as given in /etc/protocols. Default is ‘tcp’.

local[+proto]://file[;args]

file[+proto]://file[;args]

unix[+proto]://file[;args]

Listen on the UNIX socket file file, which is either an absolute or relative file name, as described above. The proto part is as described above. Optional arguments, args, control ownership and file mode of file. They are a list of assignments, separated by semicolons. The following values are allowed:

user

User name of the socket owner.

group

Owner group of the socket, if it differs from the user group.

mode

Socket file mode (octal number between ‘0’ and ‘777’).

umask

Umask to use when creating the socket (octal number between ‘0’ and ‘777’).

For example:

socket
 "unix:///var/run/socket;user=nobody;group=mail;mode=770";

The file part may be a relative file name, provided that the chdir statement is used for this component (see chdir).

Config: component: socket-type type

Sets the socket type. Allowed values for type are: ‘stream’, ‘dgram’, ‘raw’, ‘rdm’, ‘seqpacket’. Default is ‘stream’. Notice that some socket types may not be implemented by all protocol families, e.g. ‘seqpacket’ is not implemented for ‘inet’.

Config: component: max-rate n

Specifies the maximum number of times the component can be invoked in one minute; the default is unlimited. A rate of ‘0’ stands for ‘unlimited’.

Config: component: max-instances n

Sets the maximum number of simultaneously running instances of this component. It is equivalent to the maximum number of simultaneously opened connections.

Config: component: max-instances-message text

Text to send back if max-instances is reached. This is valid only for TCP sockets.

Config: component: max-ip-connections number

Maximum number of connections that can be opened simultaneously from a single IP address.

Config: component: max-ip-connections-message text

Textual message to send in reply to an incoming TCP connection from the IP address that has already reached max-ip-connections limit.

Config: component: acl { … }

Set access control list for this component. This is valid only for ‘inetd’ and ‘accept’ components. See ACL, for a detailed description of access control lists.

Config: component: access-denied-message text

Textual message to send in reply to an incoming TCP connection that has been denied by ACL settings.