lib/route-table-bsd.c

   1 /*
   2  * Copyright (c) 2012 Ed Maste. All rights reserved.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <config.h>
  18
  19 #include "route-table.h"
  20
  21 #include <sys/socket.h>
  22 #include <sys/types.h>
  23
  24 #include <net/if.h>
  25 #include <net/route.h>
  26 #include <net/if_dl.h>
  27 #include <netinet/in.h>
  28
  29 #include <string.h>
  30 #include <unistd.h>
  31
  32 #include "vlog.h"
  33
  34 VLOG_DEFINE_THIS_MODULE(route_table);
  35
  36 static int pid;
  37 static unsigned int register_count = 0;
  38
  39 bool
  40 route_table_get_name(ovs_be32 ip, char name[IFNAMSIZ])
  41 {
  42     struct {
  43         struct rt_msghdr rtm;
  44         char space[512];
  45     } rtmsg;
  46
  47     struct rt_msghdr *rtm = &rtmsg.rtm;
  48     struct sockaddr_dl *ifp = NULL;
  49     struct sockaddr_in *sin;
  50     struct sockaddr *sa;
  51     static int seq;
  52     int i, len, namelen, rtsock;
  53
  54     rtsock = socket(PF_ROUTE, SOCK_RAW, 0);
  55     if (rtsock < 0)
  56         return false;
  57
  58     memset(&rtmsg, 0, sizeof(rtmsg));
  59
  60     rtm->rtm_msglen = sizeof(struct rt_msghdr) + sizeof(struct sockaddr_in);
  61     rtm->rtm_version = RTM_VERSION;
  62     rtm->rtm_type = RTM_GET;
  63     rtm->rtm_addrs = RTA_DST | RTA_IFP;
  64     rtm->rtm_seq = ++seq;
  65
  66     sin = (struct sockaddr_in *)(rtm + 1);
  67     sin->sin_len = len = sizeof(struct sockaddr_in);
  68     sin->sin_family = AF_INET;
  69     sin->sin_addr.s_addr = ip;
  70
  71     if ((write(rtsock, (char *)&rtmsg, rtm->rtm_msglen)) < 0) {
  72         close(rtsock);
  73         return false;
  74     }
  75
  76     do {
  77         len = read(rtsock, (char *)&rtmsg, sizeof(rtmsg));
  78     } while (len > 0 && (rtmsg.rtm.rtm_seq != seq ||
  79         rtmsg.rtm.rtm_pid != pid));
  80
  81     close(rtsock);
  82
  83     if (len < 0) {
  84         return false;
  85     }
  86
  87     sa = (struct sockaddr *)(rtm + 1);
  88     for (i = 1; i; i <<= 1) {
  89         if (rtm->rtm_addrs & i) {
  90             if (i == RTA_IFP && sa->sa_family == AF_LINK &&
  91               ((struct sockaddr_dl *)sa)->sdl_nlen) {
  92                 ifp = (struct sockaddr_dl *)sa;
  93                 namelen = ifp->sdl_nlen;
  94                 if (namelen > IFNAMSIZ - 1)
  95                     namelen = IFNAMSIZ - 1;
  96                 memcpy(name, ifp->sdl_data, namelen);
  97                 name[namelen] = '\0';
  98                 return true;
  99             }
 100             sa = (struct sockaddr *)((char *)sa + SA_SIZE(sa));
 101         }
 102     }
 103     return false;
 104 }
 105
 106 void
 107 route_table_register(void)
 108 {
 109     if (!register_count)
 110     {
 111         pid = getpid();
 112     }
 113
 114     register_count++;
 115 }
 116
 117 void
 118 route_table_unregister(void)
 119 {
 120     register_count--;
 121 }
 122
 123 void
 124 route_table_run(void)
 125 {
 126 }
 127
 128 void
 129 route_table_wait(void)
 130 {
 131 }