ipsvd - examples

TCP/IP services
UDP/IP services
ipsvd instructions

TCP/IP service examples

This run script provides an identd service on 0.0.0.0:113

 #!/bin/sh
 exec tcpsvd -l0 0 113 identd

This run script provides a smtpfront-qmail service on 192.168.2.1:25, with per-host instructions through the constant database ./peers.cdb.

 #!/bin/sh
 exec 2>&1
 MAXSMTPD="`cat /var/qmail/control/concurrencyincoming`"
 exec chpst -m2000000 \
   env SMTPGREETING=smarden.org \
       MAILRULES=/etc/mailfront/smtp/mailrules \
   tcpsvd -vp -uqmaild -c"$MAXSMTPD" -x./peers.cdb 192.168.2.1 25 \
     smtpfront-qmail

This run script provides a bincimaps service on 10.0.0.14:993, with per-host concurrency limit, and with per-host instructions through the directory ./peers.

 #!/bin/sh
 exec 2>&1
 exec tcpsvd -vvp -c40 -C10 -l0 -i./peers 10.0.0.14 993 \
   bincimap-up --logtype=multilog --conf=/etc/bincimap/bincimap.conf --ssl -- \
     /usr/bin/checkpw /usr/sbin/bincimapd

This run script provides a qmail-smtpd service on 192.168.14.6:25, with per-host concurrency limit, and with per-host instructions through the directory ./peers.

 #!/bin/sh
 exec 2>&1
 exec chpst -m2000000 \
  tcpsvd -vvh -i./peers -uqmaild \
    -c40 -C'10:421 per host concurrency limit reached\r\n' \
      192.168.14.6 25 qmail-smtpd

UDP/IP service examples

This run script provides a talkd service on 192.168.1.1:517

 #!/bin/sh
 exec udpsvd -unobody:tty 192.168.1.1 517 in.talkd

This run script provides a tftpd service on 0.0.0.0:69 with per-IP-address instructions through the directory /etc/tftpd/peers

 #!/bin/sh
 cd /
 exec 2>&1
 exec udpsvd -v -lbootserver -unobody -i/etc/tftpd/peers 0 69 \
   in.tftpd -s /boot/tftpboot/

ipsvd instruction examples

This run script provides a telnetd TCP/IP service, with per-IP-address instructions through the directory ./peers

 #!/bin/sh
 exec tcpsvd -i./peers 0.0.0.0 23 in.telnetd

Per default any client IP address is allowed to connect to this service. To allow connections from 192.168.1.17, and to deny connections from anywhere else, do

touch ./peers/192.168.1.17; chmod 644 ./peers/192.168.1.17
touch ./peers/0; chmod 0 ./peers/0

To allow connections from 192.168.3.0-255, do

touch ./peers/192.168.3; chmod 644 ./peers/192.168.3

To deny connections from 10.0.*.* explicitly, do

touch ./peers/10.0; chmod 0 ./peers/10.0

To have TRUST=true set in the environment when running in.telnetd for a connection from 192.168.14.2, do

echo '+TRUST=true' >./peers/192.168.14.2; chmod 644 ./peers/192.168.14.2

To provide a sshd login for connections from 10.2.0.14 on port 23, and the usual telnetd service for all others, do

echo 'sshd -i' >./peers/10.2.0.14; chmod 744 ./peers/10.2.0.14

To allow only connections from IP addresses the (dynamic) hostnames floyd.dyn.smarden.org and greg.dyn.smarden.org currently resolve to, do

echo '=floyd.dyn.smarden.org' >./peers/0
echo '=greg.dyn.smarden.org' >>./peers/0
chmod 644 ./peers/0

See ipsvd instructions for details.

Gerrit Pape <pape@smarden.org>