netif_utils.c

   1 /*****************************************************************************
   2   Copyright (c) 2006 EMC Corporation.
   3   Copyright (c) 2011 Factor-SPE
   4
   5   This program is free software; you can redistribute it and/or modify it
   6   under the terms of the GNU General Public License as published by the Free
   7   Software Foundation; either version 2 of the License, or (at your option)
   8   any later version.
   9
  10   This program is distributed in the hope that it will be useful, but WITHOUT
  11   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13   more details.
  14
  15   You should have received a copy of the GNU General Public License along with
  16   this program; if not, write to the Free Software Foundation, Inc., 59
  17   Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18
  19   The full GNU General Public License is included in this distribution in the
  20   file called LICENSE.
  21
  22   Authors: Srinivas Aji <Aji_Srinivas@emc.com>
  23   Authors: Vitalii Demianets <dvitasgs@gmail.com>
  24
  25 ******************************************************************************/
  26
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30 #include <stdbool.h>
  31 #include <fcntl.h>
  32 #include <limits.h>
  33 #include <sys/ioctl.h>
  34 #include <sys/types.h>
  35 #include <net/if.h>
  36 #include <linux/if_ether.h>
  37 #include <linux/ethtool.h>
  38 #include <linux/sockios.h>
  39
  40 #include "netif_utils.h"
  41 #include "log.h"
  42
  43 #ifndef SYSFS_CLASS_NET
  44 #define SYSFS_CLASS_NET "/sys/class/net"
  45 #endif
  46
  47 static int netsock = -1;
  48
  49 int netsock_init(void)
  50 {
  51     netsock = socket(AF_INET, SOCK_DGRAM, 0);
  52     if(0 > netsock)
  53     {
  54         ERROR("Couldn't open inet socket for ioctls: %m\n");
  55         return -1;
  56     }
  57     return 0;
  58 }
  59
  60 int get_hwaddr(char *ifname, __u8 *hwaddr)
  61 {
  62     struct ifreq ifr;
  63     memset(&ifr, 0, sizeof(ifr));
  64     strncpy(ifr.ifr_name, ifname, IFNAMSIZ - 1);
  65     if(0 > ioctl(netsock, SIOCGIFHWADDR, &ifr))
  66     {
  67         ERROR("%s: get hw address failed: %m", ifname);
  68         return -1;
  69     }
  70     memcpy(hwaddr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
  71     return 0;
  72 }
  73
  74 int get_flags(char *ifname)
  75 {
  76     struct ifreq ifr;
  77     memset(&ifr, 0, sizeof(ifr));
  78     strncpy(ifr.ifr_name, ifname, IFNAMSIZ - 1);
  79     if(0 > ioctl(netsock, SIOCGIFFLAGS, &ifr))
  80     {
  81         ERROR("%s: get interface flags failed: %m", ifname);
  82         return -1;
  83     }
  84     return ifr.ifr_flags;
  85 }
  86
  87 int if_shutdown(char *ifname)
  88 {
  89     struct ifreq ifr;
  90
  91     memset(&ifr, 0, sizeof(ifr));
  92     /* TODO: Let's hope -1 is not a valid flag combination */
  93     if(-1 == (ifr.ifr_flags = get_flags(ifname)))
  94     {
  95         return -1;
  96     }
  97     ifr.ifr_flags &= ~IFF_UP;
  98     strncpy(ifr.ifr_name, ifname, IFNAMSIZ - 1);
  99     if(0 > ioctl(netsock, SIOCSIFFLAGS, &ifr))
 100     {
 101         ERROR("%s: set if_down flag failed: %m", ifname);
 102         return -1;
 103     }
 104     return 0;
 105 }
 106
 107 int ethtool_get_speed_duplex(char *ifname, int *speed, int *duplex)
 108 {
 109     struct ifreq ifr;
 110     memset(&ifr, 0, sizeof(ifr));
 111     strncpy(ifr.ifr_name, ifname, IFNAMSIZ - 1);
 112     struct ethtool_cmd ecmd;
 113
 114     ecmd.cmd = ETHTOOL_GSET;
 115     ifr.ifr_data = (caddr_t)&ecmd;
 116     if(0 > ioctl(netsock, SIOCETHTOOL, &ifr))
 117     {
 118         INFO("Cannot get speed/duplex for %s: %m\n", ifname);
 119         return -1;
 120     }
 121     *speed = ecmd.speed;   /* Ethtool speed is in Mbps */
 122     *duplex = ecmd.duplex; /* We have same convention as ethtool.
 123                                0 = half, 1 = full */
 124     return 0;
 125 }
 126
 127 /********* Sysfs based utility functions *************/
 128
 129 /* This sysfs stuff might break with interface renames */
 130 bool is_bridge(char *if_name)
 131 {
 132     char path[32 + IFNAMSIZ];
 133     sprintf(path, SYSFS_CLASS_NET "/%s/bridge", if_name);
 134     return (0 == access(path, R_OK));
 135 }
 136
 137 static int get_port_file(const char *if_name, const char *file)
 138 {
 139     char path[32 + IFNAMSIZ];
 140     sprintf(path, SYSFS_CLASS_NET "/%s/brport/%s", if_name, file);
 141     char buf[128];
 142     int fd;
 143     long res = -1;
 144     TSTM((fd = open(path, O_RDONLY)) >= 0, -1, "%m");
 145     int l;
 146     if((l = read(fd, buf, sizeof(buf) - 1)) < 0) {
 147         ERROR("Failed to read file %s: error %m", file);
 148         return -1;
 149     }
 150     if(0 == l)
 151     {
 152         ERROR("Empty %s file", file);
 153         goto out;
 154     }
 155     else if((sizeof(buf) - 1) == l)
 156     {
 157         ERROR("%s file too long", file);
 158         goto out;
 159     }
 160     buf[l] = 0;
 161     if('\n' == buf[l - 1])
 162         buf[l - 1] = 0;
 163     char *end;
 164     res = strtoul(buf, &end, 0);
 165     if(0 != *end || INT_MAX < res)
 166     {
 167         ERROR("Invalid %s %s", file, buf);
 168         res = -1;
 169     }
 170 out:
 171     close(fd);
 172     return res;
 173 }
 174
 175 int get_bpdu_filter(char *if_name)
 176 {
 177         return get_port_file(if_name, "bpdu_filter");
 178 }
 179
 180 int get_bridge_portno(char *if_name)
 181 {
 182         return get_port_file(if_name, "port_no");
 183 }