203 lines
6.1 KiB
Groff
203 lines
6.1 KiB
Groff
.\" Copyright (c) 2001-2003 International Computer Science Institute
|
|
.\"
|
|
.\" Permission is hereby granted, free of charge, to any person obtaining a
|
|
.\" copy of this software and associated documentation files (the "Software"),
|
|
.\" to deal in the Software without restriction, including without limitation
|
|
.\" the rights to use, copy, modify, merge, publish, distribute, sublicense,
|
|
.\" and/or sell copies of the Software, and to permit persons to whom the
|
|
.\" Software is furnished to do so, subject to the following conditions:
|
|
.\"
|
|
.\" The above copyright notice and this permission notice shall be included in
|
|
.\" all copies or substantial portions of the Software.
|
|
.\"
|
|
.\" The names and trademarks of copyright holders may not be used in
|
|
.\" advertising or publicity pertaining to the software without specific
|
|
.\" prior permission. Title to copyright in this software and any associated
|
|
.\" documentation will at all times remain with the copyright holders.
|
|
.\"
|
|
.\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
.\" IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
.\" FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
.\" AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
.\" LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
.\" FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
|
|
.\" DEALINGS IN THE SOFTWARE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd September 4, 2003
|
|
.Dt PIM 4
|
|
.Os
|
|
.\"
|
|
.Sh NAME
|
|
.Nm pim
|
|
.Nd Protocol Independent Multicast
|
|
.\"
|
|
.Sh SYNOPSIS
|
|
.Cd "options MROUTING"
|
|
.Cd "options PIM"
|
|
.Pp
|
|
.In sys/types.h
|
|
.In sys/socket.h
|
|
.In netinet/in.h
|
|
.In netinet/ip_mroute.h
|
|
.In netinet/pim.h
|
|
.Ft int
|
|
.Fn getsockopt "int s" IPPROTO_IP MRT_PIM "void *optval" "socklen_t *optlen"
|
|
.Ft int
|
|
.Fn setsockopt "int s" IPPROTO_IP MRT_PIM "const void *optval" "socklen_t optlen"
|
|
.Ft int
|
|
.Fn getsockopt "int s" IPPROTO_IPV6 MRT6_PIM "void *optval" "socklen_t *optlen"
|
|
.Ft int
|
|
.Fn setsockopt "int s" IPPROTO_IPV6 MRT6_PIM "const void *optval" "socklen_t optlen"
|
|
.Sh DESCRIPTION
|
|
.Tn PIM
|
|
is the common name for two multicast routing protocols:
|
|
Protocol Independent Multicast - Sparse Mode (PIM-SM) and
|
|
Protocol Independent Multicast - Dense Mode (PIM-DM).
|
|
.Pp
|
|
PIM-SM is a multicast routing protocol that can use the underlying
|
|
unicast routing information base or a separate multicast-capable
|
|
routing information base.
|
|
It builds unidirectional shared trees rooted at a Rendezvous
|
|
Point (RP) per group,
|
|
and optionally creates shortest-path trees per source.
|
|
.Pp
|
|
PIM-DM is a multicast routing protocol that uses the underlying
|
|
unicast routing information base to flood multicast datagrams
|
|
to all multicast routers.
|
|
Prune messages are used to prevent future datagrams from propagating
|
|
to routers with no group membership information.
|
|
.Pp
|
|
Both PIM-SM and PIM-DM are fairly complex protocols,
|
|
though PIM-SM is much more complex.
|
|
To enable PIM-SM or PIM-DM multicast routing in a router,
|
|
the user must enable multicast routing and PIM processing in the kernel
|
|
(see
|
|
.Sx SYNOPSIS
|
|
about the kernel configuration options),
|
|
and must run a PIM-SM or PIM-DM capable user-level process.
|
|
From developer's point of view,
|
|
the programming guide described in the
|
|
.Sx "Programming Guide"
|
|
section should be used to control the PIM processing in the kernel.
|
|
.\"
|
|
.Ss Programming Guide
|
|
After a multicast routing socket is open and multicast forwarding
|
|
is enabled in the kernel
|
|
(see
|
|
.Xr multicast 4 ) ,
|
|
one of the following socket options should be used to enable or disable
|
|
PIM processing in the kernel.
|
|
Note that those options require certain privilege
|
|
(i.e., root privilege):
|
|
.Bd -literal
|
|
/* IPv4 */
|
|
int v = 1; /* 1 to enable, or 0 to disable */
|
|
setsockopt(mrouter_s4, IPPROTO_IP, MRT_PIM, (void *)&v, sizeof(v));
|
|
.Ed
|
|
.Bd -literal
|
|
/* IPv6 */
|
|
int v = 1; /* 1 to enable, or 0 to disable */
|
|
setsockopt(mrouter_s6, IPPROTO_IPV6, MRT6_PIM, (void *)&v, sizeof(v));
|
|
.Ed
|
|
.Pp
|
|
After PIM processing is enabled, the multicast-capable interfaces
|
|
should be added
|
|
(see
|
|
.Xr multicast 4 ) .
|
|
In case of PIM-SM, the PIM-Register virtual interface must be added
|
|
as well.
|
|
This can be accomplished by using the following options:
|
|
.Bd -literal
|
|
/* IPv4 */
|
|
struct vifctl vc;
|
|
memset(&vc, 0, sizeof(vc));
|
|
/* Assign all vifctl fields as appropriate */
|
|
\&...
|
|
if (is_pim_register_vif)
|
|
vc.vifc_flags |= VIFF_REGISTER;
|
|
setsockopt(mrouter_s4, IPPROTO_IP, MRT_ADD_VIF, (void *)&vc,
|
|
sizeof(vc));
|
|
.Ed
|
|
.Bd -literal
|
|
/* IPv6 */
|
|
struct mif6ctl mc;
|
|
memset(&mc, 0, sizeof(mc));
|
|
/* Assign all mif6ctl fields as appropriate */
|
|
\&...
|
|
if (is_pim_register_vif)
|
|
mc.mif6c_flags |= MIFF_REGISTER;
|
|
setsockopt(mrouter_s6, IPPROTO_IPV6, MRT6_ADD_MIF, (void *)&mc,
|
|
sizeof(mc));
|
|
.Ed
|
|
.Pp
|
|
Sending or receiving of PIM packets can be accomplished by
|
|
opening first a
|
|
.Dq raw socket
|
|
(see
|
|
.Xr socket 2 ) ,
|
|
with protocol value of
|
|
.Dv IPPROTO_PIM :
|
|
.Bd -literal
|
|
/* IPv4 */
|
|
int pim_s4;
|
|
pim_s4 = socket(AF_INET, SOCK_RAW, IPPROTO_PIM);
|
|
.Ed
|
|
.Bd -literal
|
|
/* IPv6 */
|
|
int pim_s6;
|
|
pim_s6 = socket(AF_INET6, SOCK_RAW, IPPROTO_PIM);
|
|
.Ed
|
|
.Pp
|
|
Then, the following system calls can be used to send or receive PIM
|
|
packets:
|
|
.Xr sendto 2 ,
|
|
.Xr sendmsg 2 ,
|
|
.Xr recvfrom 2 ,
|
|
.Xr recvmsg 2 .
|
|
.\"
|
|
.Sh SEE ALSO
|
|
.Xr getsockopt 2 ,
|
|
.Xr recvfrom 2 ,
|
|
.Xr recvmsg 2 ,
|
|
.Xr sendmsg 2 ,
|
|
.Xr sendto 2 ,
|
|
.Xr setsockopt 2 ,
|
|
.Xr socket 2 ,
|
|
.Xr inet 4 ,
|
|
.Xr intro 4 ,
|
|
.Xr ip 4 ,
|
|
.Xr multicast 4
|
|
.\"
|
|
.Sh STANDARDS
|
|
.\" XXX the PIM-SM number must be updated after RFC 2362 is
|
|
.\" replaced by a new RFC by the end of year 2003 or so.
|
|
The PIM-SM protocol is specified in RFC 2362 (to be replaced by
|
|
.%T draft-ietf-pim-sm-v2-new-* ) .
|
|
The PIM-DM protocol is specified in
|
|
.%T draft-ietf-pim-dm-new-v2-* ) .
|
|
.\"
|
|
.Sh AUTHORS
|
|
.An -nosplit
|
|
The original IPv4 PIM kernel support for IRIX and SunOS-4.x was
|
|
implemented by
|
|
.An Ahmed Helmy
|
|
(USC and SGI).
|
|
Later the code was ported to various
|
|
.Bx
|
|
flavors and modified by
|
|
.An George Edmond Eddy
|
|
(Rusty) (ISI),
|
|
.An Hitoshi Asaeda
|
|
(WIDE Project), and
|
|
.An Pavlin Radoslavov
|
|
(USC/ISI and ICSI).
|
|
The IPv6 PIM kernel support was implemented by the KAME project
|
|
.Pq Pa http://www.kame.net ,
|
|
and was based on the IPv4 PIM kernel support.
|
|
.Pp
|
|
This manual page was written by
|
|
.An Pavlin Radoslavov
|
|
(ICSI).
|