srt(4) - NetBSD Manual Pages

SRT(4)                  NetBSD Kernel Interfaces Manual                 SRT(4)


NAME

     srt -- source-routing network interface


SYNOPSIS

     pseudo-device srt


DESCRIPTION

     The srt interface is a software interface that implements source-address-
     based routing.  Packets are directed to the srt interface using normal
     routing decision process.  Packets queued for delivery are then processed
     according to the rules established for the interface using the
     srtconfig(1) utility.

     To use an srt device, the administrator must first create the interface.
     This can be done by using the ifconfig(8) create command.  An open(2)
     call on /dev/srtN will also create a network interface with a unit number
     the same as the minor device number of that device if the interface
     doesn't exist yet.

     To be useful, the srt interface needs to be configured using srtconfig(1)
     which uses the associated srt character device /dev/srt#.

     The network interfaces should be named srt0, srt1, etc.  The srt inter-
     face supports only the open(2), close(2), and ioctl(2) operations;  other
     operations such as read(2) and write(2) are not supported.

     All standard network interface ioctl(2) calls are supported by the srt
     interface.  In addition, the following ioctl(2) calls (defined in
     <net/if_srt.h>) are supported on the srt character device:

         SRT_GETNRT   The argument is a pointer to an integer, in which the
                      number of entries in the device's routing table is
                      returned.

         SRT_GETRT    The argument is the address of a struct srt_rt.  The
                      routing table entry specified by the ``inx'' member is
                      returned.

         SRT_SETRT    The argument is the address of a struct srt_rt.  The
                      routing entry is placed into the device's routing table
                      at the index specified by the ``inx'' member.

         SRT_DELRT    The argument is the address of a struct srt_rt.  The
                      routing entry specified by the ``inx'' member is deleted
                      from the device's routing table.  (Any entries in the
                      device's routing table with higher index values are
                      renumbered.)

         SRT_SFLAGS   The argument is a pointer to an integer containing any
                      of the following flags to be set:

                      SSF_MTULOCK  If set, do not automatically update the
                                   interface's MTU.

         SRT_GFLAGS   The argument is a pointer to an integer in which the
                      current flags are returned.

         SRT_SGFLAGS  This call updates the flags in the same manner as
                      SRT_SFLAGS.  The original flags are returned in the
                      integer pointed to by the argument.

         SRT_DEBUG    Currently this is a no-op.


SEE ALSO

     srtconfig(1), inet(4), intro(4)


HISTORY

     The srt device was added in NetBSD 5.0 by der Mouse <mouse@NetBSD.org>.
     This manual page was prepared by Paul Goyette <pgoyette@NetBSD.org>.

NetBSD 10.99                    March 27, 2019                    NetBSD 10.99