user/radvd/send.c

   1 /*
   2  *   $Id: send.c,v 1.12 2002/10/28 17:28:37 psavola Exp $
   3  *
   4  *   Authors:
   5  *    Pedro Roque               <roque@di.fc.ul.pt>
   6  *    Lars Fenneberg            <lf@elemental.net>
   7  *
   8  *   This software is Copyright 1996,1997 by the above mentioned author(s),
   9  *   All Rights Reserved.
  10  *
  11  *   The license which is distributed with this software in the file COPYRIGHT
  12  *   applies to this software. If your distribution is missing this file, you
  13  *   may request it from <lutchann@litech.org>.
  14  *
  15  */
  16
  17 #include <config.h>
  18 #include <includes.h>
  19 #include <radvd.h>
  20
  21 void
  22 send_ra(int sock, struct Interface *iface, struct in6_addr *dest)
  23 {
  24         uint8_t all_hosts_addr[] = {0xff,0x02,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
  25         struct sockaddr_in6 addr;
  26         struct in6_pktinfo *pkt_info;
  27         struct msghdr mhdr;
  28         struct cmsghdr *cmsg;
  29         struct iovec iov;
  30         char chdr[CMSG_SPACE(sizeof(struct in6_pktinfo))];
  31         struct nd_router_advert *radvert;
  32         struct AdvPrefix *prefix;
  33         unsigned char buff[MSG_SIZE];
  34         int len = 0;
  35         int err;
  36
  37         /* Make sure that we've joined the all-routers multicast group */
  38         if (check_allrouters_membership(sock, iface) < 0)
  39                 log(LOG_WARNING, "problem checking all-routers membership on %s", iface->Name);
  40
  41         dlog(LOG_DEBUG, 3, "sending RA on %s", iface->Name);
  42
  43         if (dest == NULL)
  44         {
  45                 struct timeval tv;
  46
  47                 dest = (struct in6_addr *)all_hosts_addr;
  48                 gettimeofday(&tv, NULL);
  49
  50                 iface->last_multicast = tv.tv_sec;
  51         }
  52
  53         memset((void *)&addr, 0, sizeof(addr));
  54         addr.sin6_family = AF_INET6;
  55         addr.sin6_port = htons(IPPROTO_ICMPV6);
  56         memcpy(&addr.sin6_addr, dest, sizeof(struct in6_addr));
  57
  58         radvert = (struct nd_router_advert *) buff;
  59
  60         radvert->nd_ra_type  = ND_ROUTER_ADVERT;
  61         radvert->nd_ra_code  = 0;
  62         radvert->nd_ra_cksum = 0;
  63
  64         radvert->nd_ra_curhoplimit      = iface->AdvCurHopLimit;
  65         radvert->nd_ra_flags_reserved   =
  66                 (iface->AdvManagedFlag)?ND_RA_FLAG_MANAGED:0;
  67         radvert->nd_ra_flags_reserved   |=
  68                 (iface->AdvOtherConfigFlag)?ND_RA_FLAG_OTHER:0;
  69         /* Mobile IPv6 ext */
  70         radvert->nd_ra_flags_reserved   |=
  71                 (iface->AdvHomeAgentFlag)?ND_RA_FLAG_HOME_AGENT:0;
  72
  73         radvert->nd_ra_router_lifetime  = htons(iface->AdvDefaultLifetime);
  74
  75         radvert->nd_ra_reachable  = htonl(iface->AdvReachableTime);
  76         radvert->nd_ra_retransmit = htonl(iface->AdvRetransTimer);
  77
  78         len = sizeof(struct nd_router_advert);
  79
  80         prefix = iface->AdvPrefixList;
  81
  82         /*
  83          *      add prefix options
  84          */
  85
  86         while(prefix)
  87         {
  88                 if( prefix->enabled )
  89                 {
  90                         struct nd_opt_prefix_info *pinfo;
  91
  92                         pinfo = (struct nd_opt_prefix_info *) (buff + len);
  93
  94                         pinfo->nd_opt_pi_type        = ND_OPT_PREFIX_INFORMATION;
  95                         pinfo->nd_opt_pi_len         = 4;
  96                         pinfo->nd_opt_pi_prefix_len  = prefix->PrefixLen;
  97
  98                         pinfo->nd_opt_pi_flags_reserved  =
  99                                 (prefix->AdvOnLinkFlag)?ND_OPT_PI_FLAG_ONLINK:0;
 100                         pinfo->nd_opt_pi_flags_reserved |=
 101                                 (prefix->AdvAutonomousFlag)?ND_OPT_PI_FLAG_AUTO:0;
 102                         /* Mobile IPv6 ext */
 103                         pinfo->nd_opt_pi_flags_reserved |=
 104                                 (prefix->AdvRouterAddr)?ND_OPT_PI_FLAG_RADDR:0;
 105
 106                         pinfo->nd_opt_pi_valid_time     = htonl(prefix->AdvValidLifetime);
 107                         pinfo->nd_opt_pi_preferred_time = htonl(prefix->AdvPreferredLifetime);
 108                         pinfo->nd_opt_pi_reserved2      = 0;
 109
 110                         memcpy(&pinfo->nd_opt_pi_prefix, &prefix->Prefix,
 111                                sizeof(struct in6_addr));
 112
 113                         len += sizeof(*pinfo);
 114                 }
 115
 116                 prefix = prefix->next;
 117         }
 118
 119         /*
 120          *      add MTU option
 121          */
 122
 123         if (iface->AdvLinkMTU != 0) {
 124                 struct nd_opt_mtu *mtu;
 125
 126                 mtu = (struct nd_opt_mtu *) (buff + len);
 127
 128                 mtu->nd_opt_mtu_type     = ND_OPT_MTU;
 129                 mtu->nd_opt_mtu_len      = 1;
 130                 mtu->nd_opt_mtu_reserved = 0;
 131                 mtu->nd_opt_mtu_mtu      = htonl(iface->AdvLinkMTU);
 132
 133                 len += sizeof(*mtu);
 134         }
 135
 136         /*
 137          * add Source Link-layer Address option
 138          */
 139
 140         if (iface->AdvSourceLLAddress && iface->if_hwaddr_len != -1)
 141         {
 142                 uint8_t *ucp;
 143                 int i;
 144
 145                 ucp = (uint8_t *) (buff + len);
 146
 147                 *ucp++  = ND_OPT_SOURCE_LINKADDR;
 148                 *ucp++  = (uint8_t) ((iface->if_hwaddr_len + 16 + 63) >> 6);
 149
 150                 len += 2 * sizeof(uint8_t);
 151
 152                 i = (iface->if_hwaddr_len + 7) >> 3;
 153                 memcpy(buff + len, iface->if_hwaddr, i);
 154                 len += i;
 155         }
 156
 157         /*
 158          * Mobile IPv6 ext: Advertisement Interval Option to support
 159          * movement detection of mobile nodes
 160          */
 161
 162         if(iface->AdvIntervalOpt)
 163         {
 164                 struct AdvInterval a_ival;
 165                 uint32_t ival = (iface->MaxRtrAdvInterval * 1000);
 166                 a_ival.type     = ND_OPT_RTR_ADV_INTERVAL;
 167                 a_ival.length   = 1;
 168                 a_ival.reserved = 0;
 169                 a_ival.adv_ival = htonl(ival);
 170
 171                 memcpy(buff + len, &a_ival, sizeof(a_ival));
 172                 len += sizeof(a_ival);
 173         }
 174
 175         /*
 176          * Mobile IPv6 ext: Home Agent Information Option to support
 177          * Dynamic Home Agent Address Discovery
 178          */
 179
 180         if(iface->AdvHomeAgentInfo && (iface->HomeAgentPreference != 0 ||
 181                 iface->HomeAgentLifetime != iface->AdvDefaultLifetime))
 182         {
 183                 struct HomeAgentInfo ha_info;
 184                 ha_info.type            = ND_OPT_HOME_AGENT_INFO;
 185                 ha_info.length          = 1;
 186                 ha_info.reserved        = 0;
 187                 ha_info.preference      = htons(iface->HomeAgentPreference);
 188                 ha_info.lifetime        = htons(iface->HomeAgentLifetime);
 189
 190                 memcpy(buff + len, &ha_info, sizeof(ha_info));
 191                 len += sizeof(ha_info);
 192         }
 193
 194         iov.iov_len  = len;
 195         iov.iov_base = (caddr_t) buff;
 196
 197         memset(chdr, 0, sizeof(chdr));
 198         cmsg = (struct cmsghdr *) chdr;
 199
 200         cmsg->cmsg_len   = CMSG_LEN(sizeof(struct in6_pktinfo));
 201         cmsg->cmsg_level = IPPROTO_IPV6;
 202         cmsg->cmsg_type  = IPV6_PKTINFO;
 203
 204         pkt_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 205         pkt_info->ipi6_ifindex = iface->if_index;
 206         memcpy(&pkt_info->ipi6_addr, &iface->if_addr, sizeof(struct in6_addr));
 207
 208 #ifdef HAVE_SIN6_SCOPE_ID
 209         if (IN6_IS_ADDR_LINKLOCAL(&addr.sin6_addr) ||
 210                 IN6_IS_ADDR_MC_LINKLOCAL(&addr.sin6_addr))
 211                         addr.sin6_scope_id = iface->if_index;
 212 #endif
 213
 214         mhdr.msg_name = (caddr_t)&addr;
 215         mhdr.msg_namelen = sizeof(struct sockaddr_in6);
 216         mhdr.msg_iov = &iov;
 217         mhdr.msg_iovlen = 1;
 218         mhdr.msg_control = (void *) cmsg;
 219         mhdr.msg_controllen = sizeof(chdr);
 220
 221         err = sendmsg(sock, &mhdr, 0);
 222
 223         if (err < 0) {
 224                 log(LOG_WARNING, "sendmsg: %s", strerror(errno));
 225         }
 226 }