netif_utils.c

   1 /*****************************************************************************
   2   Copyright (c) 2006 EMC Corporation.
   3
   4   This program is free software; you can redistribute it and/or modify it
   5   under the terms of the GNU General Public License as published by the Free
   6   Software Foundation; either version 2 of the License, or (at your option)
   7   any later version.
   8
   9   This program is distributed in the hope that it will be useful, but WITHOUT
  10   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12   more details.
  13
  14   You should have received a copy of the GNU General Public License along with
  15   this program; if not, write to the Free Software Foundation, Inc., 59
  16   Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17
  18   The full GNU General Public License is included in this distribution in the
  19   file called LICENSE.
  20
  21   Authors: Srinivas Aji <Aji_Srinivas@emc.com>
  22
  23 ******************************************************************************/
  24
  25 #include "netif_utils.h"
  26
  27 #include <errno.h>
  28 #include <string.h>
  29 #include <stdlib.h>
  30 #include <unistd.h>
  31 #include <stdint.h>
  32 #include <sys/socket.h>
  33 #include <sys/ioctl.h>
  34 #include <fcntl.h>
  35
  36 #include <net/if.h>
  37 #include <linux/if_ether.h>
  38 #include <linux/ethtool.h>
  39 #include <linux/sockios.h>
  40
  41 #include "log.h"
  42
  43
  44
  45 int netsock = -1;
  46
  47 int netsock_init(void)
  48 {
  49   LOG("");
  50   netsock = socket(AF_INET, SOCK_DGRAM, 0);
  51   if (netsock < 0) {
  52     ERROR("Couldn't open inet socket for ioctls: %m\n");
  53     return -1;
  54   }
  55   return 0;
  56 }
  57
  58 int get_hwaddr(char *ifname, unsigned char *hwaddr)
  59 {
  60   struct ifreq ifr;
  61   memset(&ifr, 0, sizeof(ifr));
  62   strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
  63   if (ioctl(netsock, SIOCGIFHWADDR, &ifr) < 0) {
  64     ERROR("%s: get hw address failed: %m", ifname);
  65     return -1;
  66   }
  67   memcpy(hwaddr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
  68   return 0;
  69 }
  70
  71 int ethtool_get_speed_duplex(char *ifname, int *speed, int *duplex)
  72 {
  73   struct ifreq ifr;
  74   memset(&ifr, 0, sizeof(ifr));
  75   strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
  76   struct ethtool_cmd ecmd;
  77
  78   ecmd.cmd = ETHTOOL_GSET;
  79   ifr.ifr_data = (caddr_t)&ecmd;
  80   if (ioctl(netsock, SIOCETHTOOL, &ifr) < 0) {
  81     ERROR("Cannot get link status for %s: %m\n", ifname);
  82     return -1;
  83   }
  84   *speed = ecmd.speed; /* Ethtool speed is in Mbps */
  85   *duplex = ecmd.duplex; /* We have same convention as ethtool.
  86                             0 = half, 1 = full */
  87   return 0;
  88 }
  89
  90
  91 /********* Sysfs based utility functions *************/
  92
  93 /* This sysfs stuff might break with interface renames */
  94 int is_bridge(char *if_name)
  95 {
  96   char path[32 + IFNAMSIZ];
  97   sprintf(path, "/sys/class/net/%s/bridge", if_name);
  98   return (access(path, R_OK) == 0);
  99 }
 100
 101 /* This will work even less if the bridge port is renamed after being
 102    joined to the bridge.
 103 */
 104 int is_bridge_slave(char *br_name, char *if_name)
 105 {
 106   char path[32 + 2 * IFNAMSIZ];
 107   sprintf(path, "/sys/class/net/%s/brif/%s", br_name, if_name);
 108   return (access(path, R_OK) == 0);
 109 }
 110
 111 int get_bridge_portno(char *if_name)
 112 {
 113   char path[32 + IFNAMSIZ];
 114   sprintf(path, "/sys/class/net/%s/brport/port_no", if_name);
 115   char buf[128];
 116   int fd;
 117   long res = -1;
 118   TSTM((fd = open(path, O_RDONLY)) >= 0, -1, "%m");
 119   int l;
 120   TSTM((l = read(fd, buf, sizeof(buf) - 1)) >= 0, -1, "%m");
 121   if (l == 0) {
 122     ERROR("Empty port index file");
 123     goto out;
 124   }
 125   else if (l == sizeof(buf) - 1) {
 126     ERROR("port_index file too long");
 127     goto out;
 128   }
 129   buf[l] = 0;
 130   if (buf[l-1] == '\n')
 131     buf[l-1] = 0;
 132   char *end;
 133   res = strtoul(buf, &end, 0);
 134   if (*end != 0 || res > INT_MAX) {
 135     ERROR("Invalid port index %s", buf);
 136     res = -1;
 137   }
 138  out:
 139   close(fd);
 140   return res;
 141 }