519 lines
16 KiB
C
519 lines
16 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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/*
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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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* $FreeBSD$
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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 = NULL;
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static int sndcmsglen;
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static u_char *rcvcmsgbufpim = NULL;
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static int rcvcmsglen;
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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
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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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rcvcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo));
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if (rcvcmsgbufpim == NULL &&
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(rcvcmsgbufpim = malloc(rcvcmsglen)) == NULL)
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log(LOG_ERR, 0, "malloc failed");
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rcvmhpim.msg_control = (caddr_t ) rcvcmsgbufpim;
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rcvmhpim.msg_controllen = rcvcmsglen;
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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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sndcmsglen = CMSG_SPACE(sizeof(struct in6_pktinfo));
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if (sndcmsgbufpim == NULL &&
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(sndcmsgbufpim = malloc(sndcmsglen)) == NULL)
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log(LOG_ERR, 0, "malloc failed");
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sndmhpim.msg_control = (caddr_t)sndcmsgbufpim;
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sndmhpim.msg_controllen = sndcmsglen;
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cmsgp=(struct cmsghdr *)sndcmsgbufpim;
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cmsgp->cmsg_len = CMSG_LEN(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 = sndcmsglen;
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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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}
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}
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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 )
|
|
{
|
|
register int nleft = len;
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|
register u_short *w;
|
|
register int sum = 0;
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|
u_short answer = 0;
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|
|
|
/*
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|
* First create IP6 pseudo header and calculate a summary.
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|
*/
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|
w = (u_short *)src;
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|
uph.ph.ph_len = htonl(len);
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|
uph.ph.ph_nxt = IPPROTO_PIM;
|
|
|
|
/* IPv6 source address */
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|
sum += w[0];
|
|
/* XXX: necessary? */
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|
if (!(IN6_IS_ADDR_LINKLOCAL(src) || IN6_IS_ADDR_MC_LINKLOCAL(src)))
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|
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);
|
|
}
|