release/src/router/radvd/netlink.c

   1 /*
   2  *
   3  *   Authors:
   4  *    Lars Fenneberg            <lf@elemental.net>
   5  *    Reuben Hawkins            <reubenhwk@gmail.com>
   6  *
   7  *   This software is Copyright 1996,1997 by the above mentioned author(s),
   8  *   All Rights Reserved.
   9  *
  10  *   The license which is distributed with this software in the file COPYRIGHT
  11  *   applies to this software. If your distribution is missing this file, you
  12  *   may request it from <pekkas@netcore.fi>.
  13  *
  14  */
  15
  16 #include "config.h"
  17 #include "radvd.h"
  18 #include "log.h"
  19 #include "netlink.h"
  20
  21 #include <asm/types.h>
  22 #include <sys/socket.h>
  23 #include <linux/netlink.h>
  24 #include <linux/rtnetlink.h>
  25 #include <net/if.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <errno.h>
  29 #include <string.h>
  30
  31 #ifndef SOL_NETLINK
  32 #define SOL_NETLINK     270
  33 #endif
  34
  35 void process_netlink_msg(int sock)
  36 {
  37         int len;
  38         char buf[4096];
  39         struct iovec iov = { buf, sizeof(buf) };
  40         struct sockaddr_nl sa;
  41         struct msghdr msg = { (void *)&sa, sizeof(sa), &iov, 1, NULL, 0, 0 };
  42         struct nlmsghdr *nh;
  43         struct ifinfomsg * ifinfo;
  44         char ifname[IF_NAMESIZE] = {""};
  45
  46         len = recvmsg (sock, &msg, 0);
  47         if (len == -1) {
  48                 flog(LOG_ERR, "recvmsg failed: %s", strerror(errno));
  49         }
  50
  51         for (nh = (struct nlmsghdr *) buf; NLMSG_OK (nh, len); nh = NLMSG_NEXT (nh, len)) {
  52                 /* The end of multipart message. */
  53                 if (nh->nlmsg_type == NLMSG_DONE)
  54                         return;
  55
  56                 if (nh->nlmsg_type == NLMSG_ERROR) {
  57                         flog(LOG_ERR, "%s:%d Some type of netlink error.\n", __FILE__, __LINE__);
  58                         abort();
  59                 }
  60
  61                 /* Continue with parsing payload. */
  62                 ifinfo = NLMSG_DATA(nh);
  63                 if_indextoname(ifinfo->ifi_index, ifname);
  64                 if (ifinfo->ifi_flags & IFF_RUNNING) {
  65                         dlog(LOG_DEBUG, 3, "%s, ifindex %d, flags is running", ifname, ifinfo->ifi_index);
  66                 }
  67                 else {
  68                         dlog(LOG_DEBUG, 3, "%s, ifindex %d, flags is *NOT* running", ifname, ifinfo->ifi_index);
  69                 }
  70                 reload_config();
  71         }
  72 }
  73
  74 int netlink_socket(void)
  75 {
  76         int rc, sock;
  77         unsigned int val = 1;
  78         struct sockaddr_nl snl;
  79
  80         sock = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
  81         if (sock == -1) {
  82                 flog(LOG_ERR, "Unable to open netlink socket: %s", strerror(errno));
  83         }
  84 #ifdef NETLINK_NO_ENOBUFS
  85         else if (setsockopt(sock, SOL_NETLINK, NETLINK_NO_ENOBUFS, &val, sizeof(val)) < 0 ) {
  86                 flog(LOG_ERR, "Unable to setsockopt NETLINK_NO_ENOBUFS: %s", strerror(errno));
  87         }
  88 #endif
  89
  90         memset(&snl, 0, sizeof(snl));
  91         snl.nl_family = AF_NETLINK;
  92         snl.nl_groups = RTMGRP_LINK;
  93
  94         rc = bind(sock, (struct sockaddr*)&snl, sizeof(snl));
  95         if (rc == -1) {
  96                 flog(LOG_ERR, "Unable to bind netlink socket: %s", strerror(errno));
  97                 close(sock);
  98                 sock = -1;
  99         }
 100
 101         return sock;
 102 }
 103