0fea3d5165
kernel IPv6 multicast routing support. pim6 dense mode daemon pim6 sparse mode daemon netstat support of IPv6 multicast routing statistics Merging to the current and testing with other existing multicast routers is done by Tatsuya Jinmei <jinmei@kame.net>, who writes and maintainances the base code in KAME distribution. Make world check and kernel build check was also successful.
508 lines
15 KiB
C
508 lines
15 KiB
C
/*
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* Copyright (C) 1999 LSIIT Laboratory.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the project nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* Copyright (C) 1998 WIDE Project.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the project nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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/*
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* Questions concerning this software should be directed to
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* Mickael Hoerdt (hoerdt@clarinet.u-strasbg.fr) LSIIT Strasbourg.
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*
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*/
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/*
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* This program has been derived from pim6dd.
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* The pim6dd program is covered by the license in the accompanying file
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* named "LICENSE.pim6dd".
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*/
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/*
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* This program has been derived from pimd.
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* The pimd program is covered by the license in the accompanying file
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* named "LICENSE.pimd".
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*
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*/
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#include <sys/param.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/uio.h>
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#include <errno.h>
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#include <netinet/in.h>
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#include <string.h>
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#include <netinet6/ip6_mroute.h>
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#include <netinet6/pim6.h>
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#include <netinet/ip6.h>
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#include <arpa/inet.h>
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#include <stdlib.h>
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#include <syslog.h>
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#include <signal.h>
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#include "mld6.h"
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#include "defs.h"
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#include "kern.h"
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#include "pim6.h"
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#include "pimd.h"
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#include "pim6_proto.h"
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#include "inet6.h"
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#include "debug.h"
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struct sockaddr_in6 allpim6routers_group;
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int pim6_socket;
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char *pim6_recv_buf;
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char *pim6_send_buf;
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static struct sockaddr_in6 from;
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static struct iovec sndiovpim[2];
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static struct iovec rcviovpim[2];
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static struct msghdr sndmhpim,
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rcvmhpim;
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static u_char sndcmsgbufpim[CMSG_SPACE(sizeof(struct in6_pktinfo))];
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static u_char rcvcmsgbufpim[CMSG_SPACE(sizeof(struct in6_pktinfo))];
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/*
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* Local function definitions.
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*/
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static void pim6_read __P((int f, fd_set *rfd));
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static void accept_pim6 __P((int recvlen));
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static int pim6_cksum __P((u_short *, struct in6_addr *,
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struct in6_addr *, int));
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void init_pim6()
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{
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struct cmsghdr *cmsgp;
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int on;
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if ( (pim6_recv_buf = malloc( RECV_BUF_SIZE)) == NULL ||
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(pim6_send_buf = malloc (RECV_BUF_SIZE)) == NULL)
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log(LOG_ERR,errno,"pim6 buffer allocation");
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IF_DEBUG(DEBUG_KERN)
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log(LOG_DEBUG,0,"%d octets allocated for the emit/recept buffer pim6",RECV_BUF_SIZE);
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if( (pim6_socket = socket(AF_INET6,SOCK_RAW,IPPROTO_PIM)) < 0 )
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log(LOG_ERR,errno,"pim6_socket");
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k_set_rcvbuf(pim6_socket,SO_RECV_BUF_SIZE_MAX,SO_RECV_BUF_SIZE_MIN);
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k_set_hlim(pim6_socket,MINHLIM);
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k_set_loop(pim6_socket,FALSE);
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memset(&allpim6routers_group, 0, sizeof(allpim6routers_group));
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allpim6routers_group.sin6_len = sizeof(allpim6routers_group);
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allpim6routers_group.sin6_family = AF_INET6;
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if (inet_pton(AF_INET6, "ff02::d",
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(void *)&allpim6routers_group.sin6_addr) != 1 )
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log(LOG_ERR, 0, "inet_pton failed for ff02::d");
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memset(&sockaddr6_d, 0, sizeof(sockaddr6_d));
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sockaddr6_d.sin6_len = sizeof(sockaddr6_d);
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sockaddr6_d.sin6_family = AF_INET6;
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if (inet_pton(AF_INET6, "ff00::",
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(void *)&sockaddr6_d.sin6_addr) != 1)
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log(LOG_ERR, 0, "inet_pton failed for ff00::");
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/* specify to tell receiving interface */
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on = 1;
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#ifdef IPV6_RECVPKTINFO
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if (setsockopt(pim6_socket, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
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sizeof(on)) < 0)
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log(LOG_ERR, errno, "setsockopt(IPV6_RECVPKTINFO)");
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#else
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if (setsockopt(pim6_socket, IPPROTO_IPV6, IPV6_PKTINFO, &on,
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sizeof(on)) < 0)
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log(LOG_ERR, errno, "setsockopt(IPV6_PKTINFO)");
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#endif
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/* initialize msghdr for receiving packets */
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rcviovpim[0].iov_base = (caddr_t) pim6_recv_buf;
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rcviovpim[0].iov_len = RECV_BUF_SIZE;
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rcvmhpim.msg_name = (caddr_t ) &from;
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rcvmhpim.msg_namelen = sizeof (from);
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rcvmhpim.msg_iov = rcviovpim;
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rcvmhpim.msg_iovlen = 1;
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rcvmhpim.msg_control = (caddr_t ) rcvcmsgbufpim;
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rcvmhpim.msg_controllen = sizeof (rcvcmsgbufpim);
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sndmhpim.msg_namelen=sizeof(struct sockaddr_in6);
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sndmhpim.msg_iov=sndiovpim;
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sndmhpim.msg_iovlen=1;
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sndmhpim.msg_control=(caddr_t)sndcmsgbufpim;
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sndmhpim.msg_controllen=sizeof(sndcmsgbufpim);
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cmsgp=(struct cmsghdr *)sndcmsgbufpim;
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cmsgp->cmsg_len=CMSG_SPACE(sizeof(struct in6_pktinfo));
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cmsgp->cmsg_level=IPPROTO_IPV6;
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cmsgp->cmsg_type=IPV6_PKTINFO;
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if ( register_input_handler(pim6_socket, pim6_read) <0)
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log(LOG_ERR,0,"Registering pim6 socket");
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/* Initialize the building Join/Prune messages working area */
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build_jp_message_pool = (build_jp_message_t *)NULL;
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build_jp_message_pool_counter = 0;
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}
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/* Read a PIM message */
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static void
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pim6_read(f, rfd)
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int f;
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fd_set *rfd;
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{
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register int pim6_recvlen;
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#ifdef SYSV
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sigset_t block, oblock;
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#else
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register int omask;
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#endif
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pim6_recvlen = recvmsg(pim6_socket,&rcvmhpim,0);
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if (pim6_recvlen < 0) {
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if (errno != EINTR)
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log(LOG_ERR, errno, "PIM6 recvmsg");
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return;
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}
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#ifdef SYSV
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(void)sigemptyset(&block);
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(void)sigaddset(&block, SIGALRM);
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if (sigprocmask(SIG_BLOCK, &block, &oblock) < 0)
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log(LOG_ERR, errno, "sigprocmask");
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#else
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/* Use of omask taken from main() */
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omask = sigblock(sigmask(SIGALRM));
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#endif /* SYSV */
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accept_pim6(pim6_recvlen);
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#ifdef SYSV
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(void)sigprocmask(SIG_SETMASK, &oblock, (sigset_t *)NULL);
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#else
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(void)sigsetmask(omask);
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#endif /* SYSV */
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}
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static void
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accept_pim6(pimlen)
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int pimlen;
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{
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register struct pim *pim;
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struct sockaddr_in6 dst;
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struct in6_pktinfo *pi=NULL;
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struct sockaddr_in6 *src = (struct sockaddr_in6 *)rcvmhpim.msg_name;
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struct cmsghdr *cm;
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int ifindex=0;
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/* sanity check */
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if (pimlen < sizeof(pim)) {
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log(LOG_WARNING, 0,
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"data field too short (%u bytes) for PIM header, from %s",
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pimlen, inet6_fmt(&src->sin6_addr));
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return;
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}
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pim = (struct pim *)rcvmhpim.msg_iov[0].iov_base;
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/* extract vital information via Advanced API */
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for(cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhpim);
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cm;
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cm =(struct cmsghdr *)CMSG_NXTHDR(&rcvmhpim , cm ))
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{
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if( cm->cmsg_level == IPPROTO_IPV6 &&
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cm->cmsg_type == IPV6_PKTINFO &&
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cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo)))
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{
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pi=(struct in6_pktinfo *)(CMSG_DATA(cm));
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dst.sin6_addr=pi->ipi6_addr;
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ifindex = pi->ipi6_ifindex;
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if (IN6_IS_ADDR_LINKLOCAL(&dst.sin6_addr))
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dst.sin6_scope_id = ifindex;
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else
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dst.sin6_scope_id = 0;
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}
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}
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if(pi==NULL)
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log(LOG_ERR,0,"pim6_socket : unable to get destination packet");
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if(ifindex==0)
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log(LOG_ERR,0,"pim6_socket : unable to get ifindex");
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#define NOSUCHDEF
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#ifdef NOSUCHDEF /* TODO: delete. Too noisy */
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IF_DEBUG(DEBUG_PIM_DETAIL) {
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IF_DEBUG(DEBUG_PIM) {
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log(LOG_DEBUG, 0, "Receiving %s from %s",
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packet_kind(IPPROTO_PIM, pim->pim_type, 0),
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inet6_fmt(&src->sin6_addr));
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}
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}
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#endif /* NOSUCHDEF */
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/* Check of PIM version is already done in the kernel */
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/*
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* TODO: check the dest. is ALL_PIM_ROUTERS (if multicast address)
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* is it necessary?
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*/
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/* Checksum verification is done in the kernel. */
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switch (pim->pim_type) {
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case PIM_HELLO:
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receive_pim6_hello(src, (char *)(pim), pimlen);
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break;
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case PIM_REGISTER:
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receive_pim6_register(src, &dst, (char *)(pim), pimlen);
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break;
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case PIM_REGISTER_STOP:
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receive_pim6_register_stop(src, &dst, (char *)(pim), pimlen);
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break;
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case PIM_JOIN_PRUNE:
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receive_pim6_join_prune(src, &dst, (char *)(pim), pimlen);
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break;
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case PIM_BOOTSTRAP:
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receive_pim6_bootstrap(src, &dst, (char *)(pim), pimlen);
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break;
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case PIM_ASSERT:
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receive_pim6_assert(src, &dst, (char *)(pim), pimlen);
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break;
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case PIM_GRAFT:
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pim6dstat.in_pim6_graft++;
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log(LOG_INFO, 0, "ignore %s from %s",
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packet_kind(IPPROTO_PIM, pim->pim_type, 0),
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inet6_fmt(&src->sin6_addr));
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break;
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case PIM_GRAFT_ACK:
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pim6dstat.in_pim6_graft_ack++;
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log(LOG_INFO, 0, "ignore %s from %s",
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packet_kind(IPPROTO_PIM, pim->pim_type, 0),
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inet6_fmt(&src->sin6_addr));
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break;
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case PIM_CAND_RP_ADV:
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receive_pim6_cand_rp_adv(src, &dst, (char *)(pim), pimlen);
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break;
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default:
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log(LOG_INFO, 0,
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"ignore unknown PIM message code %u from %s",
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pim->pim_type,
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inet6_fmt(&src->sin6_addr));
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break;
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}
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}
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void
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send_pim6(char *buf, struct sockaddr_in6 *src,
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struct sockaddr_in6 *dst, int type, int datalen)
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{
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struct pim *pim;
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int setloop=0;
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int ifindex=0;
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int sendlen=sizeof(struct pim)+datalen;
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struct cmsghdr *cmsgp;
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struct in6_pktinfo *sndpktinfo;
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sndiovpim[0].iov_base=(caddr_t)buf;
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sndiovpim[0].iov_len=datalen+sizeof(struct pim);
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cmsgp=(struct cmsghdr *)sndcmsgbufpim;
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sndpktinfo=(struct in6_pktinfo *)CMSG_DATA(cmsgp);
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sndmhpim.msg_name=(caddr_t)dst;
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pim = (struct pim *)buf;
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pim->pim_type = type;
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pim->pim_ver = PIM_PROTOCOL_VERSION;
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pim->pim_rsv = 0;
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pim->pim_cksum = 0;
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if(pim->pim_type == PIM_REGISTER)
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{
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sendlen = sizeof(struct pim)+sizeof(pim_register_t);
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}
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pim->pim_cksum = pim6_cksum((u_int16 *)pim,
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&src->sin6_addr, &dst->sin6_addr,
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sendlen);
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if (IN6_IS_ADDR_MULTICAST(&dst->sin6_addr))
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{
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if (!IN6_IS_ADDR_LINKLOCAL(&src->sin6_addr))
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{
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log(LOG_WARNING, 0,
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"trying to send pim multicast packet "
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"with non linklocal src(%s), ignoring",
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inet6_fmt(&src->sin6_addr));
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return;
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}
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sndmhpim.msg_control=NULL;
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sndmhpim.msg_controllen=0;
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ifindex=src->sin6_scope_id;
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k_set_if(pim6_socket , ifindex);
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if( IN6_ARE_ADDR_EQUAL(&dst->sin6_addr,
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&allnodes_group.sin6_addr) ||
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IN6_ARE_ADDR_EQUAL(&dst->sin6_addr,
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&allrouters_group.sin6_addr) ||
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IN6_ARE_ADDR_EQUAL(&dst->sin6_addr,
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&allpim6routers_group.sin6_addr))
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{
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setloop=1;
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k_set_loop(pim6_socket, TRUE);
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}
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}
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else
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{
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sndmhpim.msg_control=(caddr_t)sndcmsgbufpim;
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sndmhpim.msg_controllen=sizeof(sndcmsgbufpim);
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sndpktinfo->ipi6_ifindex=src->sin6_scope_id;
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memcpy(&sndpktinfo->ipi6_addr, &src->sin6_addr,
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sizeof(sndpktinfo->ipi6_addr));
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}
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if( sendmsg(pim6_socket, &sndmhpim, 0) <0 )
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if (errno == ENETDOWN)
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check_vif_state();
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else
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log(LOG_WARNING, errno, "sendmsg from %s to %s",
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inet6_fmt(&src->sin6_addr),
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inet6_fmt(&dst->sin6_addr));
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if(setloop)
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k_set_loop(pim6_socket, FALSE);
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return;
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}
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/* ============================== */
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/*
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* Checksum routine for Internet Protocol family headers (Portable Version).
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*
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* This routine is very heavily used in the network
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* code and should be modified for each CPU to be as fast as possible.
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*/
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#define ADDCARRY(x) (x > 65535 ? x -= 65535 : x)
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#define REDUCE {l_util.l = sum; sum = l_util.s[0] + l_util.s[1]; ADDCARRY(sum);}
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static union {
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u_short phs[4];
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struct {
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u_long ph_len;
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u_char ph_zero[3];
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u_char ph_nxt;
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} ph;
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} uph;
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/*
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* Our algorithm is simple, using a 32 bit accumulator (sum), we add
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* sequential 16 bit words to it, and at the end, fold back all the
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* carry bits from the top 16 bits into the lower 16 bits.
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*/
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int pim6_cksum(u_short *addr, struct in6_addr *src ,struct in6_addr *dst , int len )
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{
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register int nleft = len;
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register u_short *w;
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register int sum = 0;
|
|
u_short answer = 0;
|
|
|
|
/*
|
|
* First create IP6 pseudo header and calculate a summary.
|
|
*/
|
|
w = (u_short *)src;
|
|
uph.ph.ph_len = htonl(len);
|
|
uph.ph.ph_nxt = IPPROTO_PIM;
|
|
|
|
/* IPv6 source address */
|
|
sum += w[0];
|
|
/* XXX: necessary? */
|
|
if (!(IN6_IS_ADDR_LINKLOCAL(src) || IN6_IS_ADDR_MC_LINKLOCAL(src)))
|
|
sum += w[1];
|
|
sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
|
|
sum += w[6]; sum += w[7];
|
|
/* IPv6 destination address */
|
|
w = (u_short *)dst;
|
|
sum += w[0];
|
|
/* XXX: necessary? */
|
|
if (!(IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MC_LINKLOCAL(dst)))
|
|
sum += w[1];
|
|
sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
|
|
sum += w[6]; sum += w[7];
|
|
/* Payload length and upper layer identifier */
|
|
sum += uph.phs[0]; sum += uph.phs[1];
|
|
sum += uph.phs[2]; sum += uph.phs[3];
|
|
|
|
/*
|
|
* Secondly calculate a summary of the first mbuf excluding offset.
|
|
*/
|
|
w = addr;
|
|
while (nleft > 1) {
|
|
sum += *w++;
|
|
nleft -= 2;
|
|
}
|
|
|
|
/* mop up an odd byte, if necessary */
|
|
if (nleft == 1) {
|
|
*(u_char *)(&answer) = *(u_char *)w ;
|
|
sum += answer;
|
|
}
|
|
|
|
/* add back carry outs from top 16 bits to low 16 bits */
|
|
sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */
|
|
sum += (sum >> 16); /* add carry */
|
|
answer = ~sum; /* truncate to 16 bits */
|
|
return(answer);
|
|
}
|