zebra/rtread_getmsg.c

   1 /*
   2  * Kernel routing table readup by getmsg(2)
   3  * Copyright (C) 1999 Michael Handler
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <zebra.h>
  23
  24 #include "prefix.h"
  25 #include "log.h"
  26 #include "if.h"
  27 #include "vrf.h"
  28 #include "vty.h"
  29
  30 #include "zebra/rib.h"
  31 #include "zebra/zserv.h"
  32
  33 /* Thank you, Solaris, for polluting application symbol namespace. */
  34 #undef hook_register
  35 #undef hook_unregister
  36
  37 #include <sys/stream.h>
  38 #include <sys/tihdr.h>
  39
  40 /* Solaris defines these in both <netinet/in.h> and <inet/in.h>, sigh */
  41 #ifdef SUNOS_5
  42 #include <sys/tiuser.h>
  43 #ifndef T_CURRENT
  44 #define T_CURRENT       MI_T_CURRENT
  45 #endif /* T_CURRENT */
  46 #ifndef IRE_CACHE
  47 #define IRE_CACHE               0x0020  /* Cached Route entry */
  48 #endif /* IRE_CACHE */
  49 #ifndef IRE_HOST_REDIRECT
  50 #define IRE_HOST_REDIRECT       0x0200  /* Host route entry from redirects */
  51 #endif /* IRE_HOST_REDIRECT */
  52 #ifndef IRE_CACHETABLE
  53 #define IRE_CACHETABLE (IRE_CACHE | IRE_BROADCAST | IRE_LOCAL | IRE_LOOPBACK)
  54 #endif /* IRE_CACHETABLE */
  55 #undef IPOPT_EOL
  56 #undef IPOPT_NOP
  57 #undef IPOPT_LSRR
  58 #undef IPOPT_RR
  59 #undef IPOPT_SSRR
  60 #endif /* SUNOS_5 */
  61
  62 #include <inet/common.h>
  63 #include <inet/ip.h>
  64 #include <inet/mib2.h>
  65
  66 /* device to read IP routing table from */
  67 #ifndef _PATH_GETMSG_ROUTE
  68 #define _PATH_GETMSG_ROUTE      "/dev/ip"
  69 #endif /* _PATH_GETMSG_ROUTE */
  70
  71 #define RT_BUFSIZ               8192
  72
  73 static void handle_route_entry(mib2_ipRouteEntry_t *routeEntry)
  74 {
  75         struct prefix prefix;
  76         struct in_addr tmpaddr, gateway;
  77         union g_addr *ggateway;
  78         u_char zebra_flags = 0;
  79
  80         if (routeEntry->ipRouteInfo.re_ire_type & IRE_CACHETABLE)
  81                 return;
  82
  83         if (routeEntry->ipRouteInfo.re_ire_type & IRE_HOST_REDIRECT)
  84                 zebra_flags |= ZEBRA_FLAG_SELFROUTE;
  85
  86         prefix.family = AF_INET;
  87
  88         tmpaddr.s_addr = routeEntry->ipRouteDest;
  89         prefix.u.prefix4 = tmpaddr;
  90
  91         tmpaddr.s_addr = routeEntry->ipRouteMask;
  92         prefix.prefixlen = ip_masklen(tmpaddr);
  93
  94         gateway.s_addr = routeEntry->ipRouteNextHop;
  95         ggateway = (union g_addr *)&gateway;
  96
  97         rib_add(AFI_IP, SAFI_UNICAST, VRF_DEFAULT, ZEBRA_ROUTE_KERNEL, 0,
  98                 zebra_flags, &prefix, NULL, ggateway, NULL, 0, 0, 0, 0, 0);
  99 }
 100
 101 void route_read(struct zebra_ns *zns)
 102 {
 103         char storage[RT_BUFSIZ];
 104
 105         struct T_optmgmt_req *TLIreq = (struct T_optmgmt_req *)storage;
 106         struct T_optmgmt_ack *TLIack = (struct T_optmgmt_ack *)storage;
 107         struct T_error_ack *TLIerr = (struct T_error_ack *)storage;
 108
 109         struct opthdr *MIB2hdr;
 110
 111         mib2_ipRouteEntry_t *routeEntry, *lastRouteEntry;
 112
 113         struct strbuf msgdata;
 114         int flags, dev, retval, process;
 115
 116         if ((dev = open(_PATH_GETMSG_ROUTE, O_RDWR)) == -1) {
 117                 zlog_warn("can't open %s: %s", _PATH_GETMSG_ROUTE,
 118                           safe_strerror(errno));
 119                 return;
 120         }
 121
 122         TLIreq->PRIM_type = T_OPTMGMT_REQ;
 123         TLIreq->OPT_offset = sizeof(struct T_optmgmt_req);
 124         TLIreq->OPT_length = sizeof(struct opthdr);
 125         TLIreq->MGMT_flags = T_CURRENT;
 126
 127         MIB2hdr = (struct opthdr *)&TLIreq[1];
 128
 129         MIB2hdr->level = MIB2_IP;
 130         MIB2hdr->name = 0;
 131         MIB2hdr->len = 0;
 132
 133         msgdata.buf = storage;
 134         msgdata.len = sizeof(struct T_optmgmt_req) + sizeof(struct opthdr);
 135
 136         flags = 0;
 137
 138         if (putmsg(dev, &msgdata, NULL, flags) == -1) {
 139                 zlog_warn("putmsg failed: %s", safe_strerror(errno));
 140                 goto exit;
 141         }
 142
 143         MIB2hdr = (struct opthdr *)&TLIack[1];
 144         msgdata.maxlen = sizeof(storage);
 145
 146         while (1) {
 147                 flags = 0;
 148                 retval = getmsg(dev, &msgdata, NULL, &flags);
 149
 150                 if (retval == -1) {
 151                         zlog_warn("getmsg(ctl) failed: %s",
 152                                   safe_strerror(errno));
 153                         goto exit;
 154                 }
 155
 156                 /* This is normal loop termination */
 157                 if (retval == 0
 158                     && (size_t)msgdata.len >= sizeof(struct T_optmgmt_ack)
 159                     && TLIack->PRIM_type == T_OPTMGMT_ACK
 160                     && TLIack->MGMT_flags == T_SUCCESS && MIB2hdr->len == 0)
 161                         break;
 162
 163                 if ((size_t)msgdata.len >= sizeof(struct T_error_ack)
 164                     && TLIerr->PRIM_type == T_ERROR_ACK) {
 165                         zlog_warn("getmsg(ctl) returned T_ERROR_ACK: %s",
 166                                   safe_strerror((TLIerr->TLI_error == TSYSERR)
 167                                                         ? TLIerr->UNIX_error
 168                                                         : EPROTO));
 169                         break;
 170                 }
 171
 172                 /* should dump more debugging info to the log statement,
 173                    like what GateD does in this instance, but not
 174                    critical yet. */
 175                 if (retval != MOREDATA
 176                     || (size_t)msgdata.len < sizeof(struct T_optmgmt_ack)
 177                     || TLIack->PRIM_type != T_OPTMGMT_ACK
 178                     || TLIack->MGMT_flags != T_SUCCESS) {
 179                         errno = ENOMSG;
 180                         zlog_warn("getmsg(ctl) returned bizarreness");
 181                         break;
 182                 }
 183
 184                 /* MIB2_IP_21 is the the pseudo-MIB2 ipRouteTable
 185                    entry, see <inet/mib2.h>. "This isn't the MIB data
 186                    you're looking for." */
 187                 process = (MIB2hdr->level == MIB2_IP
 188                            && MIB2hdr->name == MIB2_IP_21)
 189                                   ? 1
 190                                   : 0;
 191
 192                 /* getmsg writes the data buffer out completely, not
 193                    to the closest smaller multiple. Unless reassembling
 194                    data structures across buffer boundaries is your idea
 195                    of a good time, set maxlen to the closest smaller
 196                    multiple of the size of the datastructure you're
 197                    retrieving. */
 198                 msgdata.maxlen =
 199                         sizeof(storage)
 200                         - (sizeof(storage) % sizeof(mib2_ipRouteEntry_t));
 201
 202                 msgdata.len = 0;
 203                 flags = 0;
 204
 205                 do {
 206                         retval = getmsg(dev, NULL, &msgdata, &flags);
 207
 208                         if (retval == -1) {
 209                                 zlog_warn("getmsg(data) failed: %s",
 210                                           safe_strerror(errno));
 211                                 goto exit;
 212                         }
 213
 214                         if (!(retval == 0 || retval == MOREDATA)) {
 215                                 zlog_warn("getmsg(data) returned %d", retval);
 216                                 goto exit;
 217                         }
 218
 219                         if (process) {
 220                                 if (msgdata.len % sizeof(mib2_ipRouteEntry_t)
 221                                     != 0) {
 222                                         zlog_warn(
 223                                                 "getmsg(data) returned "
 224                                                 "msgdata.len = %d (%% sizeof (mib2_ipRouteEntry_t) != 0)",
 225                                                 msgdata.len);
 226                                         goto exit;
 227                                 }
 228
 229                                 routeEntry = (mib2_ipRouteEntry_t *)msgdata.buf;
 230                                 lastRouteEntry =
 231                                         (mib2_ipRouteEntry_t *)(msgdata.buf
 232                                                                 + msgdata.len);
 233                                 do {
 234                                         handle_route_entry(routeEntry);
 235                                 } while (++routeEntry < lastRouteEntry);
 236                         }
 237                 } while (retval == MOREDATA);
 238         }
 239
 240 exit:
 241         close(dev);
 242 }
 243
 244 /* Only implemented for netlink method */
 245 void macfdb_read(struct zebra_ns *zns)
 246 {
 247 }
 248
 249 void macfdb_read_for_bridge(struct zebra_ns *zns, struct interface *ifp,
 250                             struct interface *br_if)
 251 {
 252 }
 253
 254 void neigh_read(struct zebra_ns *zns)
 255 {
 256 }
 257
 258 void neigh_read_for_vlan(struct zebra_ns *zns, struct interface *vlan_if)
 259 {
 260 }