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 int netsock = -1;
  44
  45 int netsock_init(void)
  46 {
  47         LOG("");
  48         netsock = socket(AF_INET, SOCK_DGRAM, 0);
  49         if (netsock < 0) {
  50                 ERROR("Couldn't open inet socket for ioctls: %m\n");
  51                 return -1;
  52         }
  53         return 0;
  54 }
  55
  56 int get_hwaddr(char *ifname, unsigned char *hwaddr)
  57 {
  58         struct ifreq ifr;
  59         memset(&ifr, 0, sizeof(ifr));
  60         strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
  61         if (ioctl(netsock, SIOCGIFHWADDR, &ifr) < 0) {
  62                 ERROR("%s: get hw address failed: %m", ifname);
  63                 return -1;
  64         }
  65         memcpy(hwaddr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
  66         return 0;
  67 }
  68
  69 int ethtool_get_speed_duplex(char *ifname, int *speed, int *duplex)
  70 {
  71         struct ifreq ifr;
  72         memset(&ifr, 0, sizeof(ifr));
  73         strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
  74         struct ethtool_cmd ecmd;
  75
  76         ecmd.cmd = ETHTOOL_GSET;
  77         ifr.ifr_data = (caddr_t) & ecmd;
  78         if (ioctl(netsock, SIOCETHTOOL, &ifr) < 0) {
  79                 ERROR("Cannot get link status for %s: %m\n", ifname);
  80                 return -1;
  81         }
  82         *speed = ecmd.speed;    /* Ethtool speed is in Mbps */
  83         *duplex = ecmd.duplex;  /* We have same convention as ethtool.
  84                                    0 = half, 1 = full */
  85         return 0;
  86 }
  87
  88 /********* Sysfs based utility functions *************/
  89
  90 /* This sysfs stuff might break with interface renames */
  91 int is_bridge(char *if_name)
  92 {
  93         char path[32 + IFNAMSIZ];
  94         sprintf(path, "/sys/class/net/%s/bridge", if_name);
  95         return (access(path, R_OK) == 0);
  96 }
  97
  98 /* This will work even less if the bridge port is renamed after being
  99    joined to the bridge.
 100 */
 101 int is_bridge_slave(char *br_name, char *if_name)
 102 {
 103         char path[32 + 2 * IFNAMSIZ];
 104         sprintf(path, "/sys/class/net/%s/brif/%s", br_name, if_name);
 105         return (access(path, R_OK) == 0);
 106 }
 107
 108 int get_bridge_portno(char *if_name)
 109 {
 110         char path[32 + IFNAMSIZ];
 111         sprintf(path, "/sys/class/net/%s/brport/port_no", if_name);
 112         char buf[128];
 113         int fd;
 114         long res = -1;
 115         TSTM((fd = open(path, O_RDONLY)) >= 0, -1, "%m");
 116         int l;
 117         TSTM((l = read(fd, buf, sizeof(buf) - 1)) >= 0, -1, "%m");
 118         if (l == 0) {
 119                 ERROR("Empty port index file");
 120                 goto out;
 121         } else if (l == sizeof(buf) - 1) {
 122                 ERROR("port_index file too long");
 123                 goto out;
 124         }
 125         buf[l] = 0;
 126         if (buf[l - 1] == '\n')
 127                 buf[l - 1] = 0;
 128         char *end;
 129         res = strtoul(buf, &end, 0);
 130         if (*end != 0 || res > INT_MAX) {
 131                 ERROR("Invalid port index %s", buf);
 132                 res = -1;
 133         }
 134       out:
 135         close(fd);
 136         return res;
 137 }