src/udev/udev-builtin-net_id.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2012 Kay Sievers <kay@vrfy.org>
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 /*
  21  * prefixes:
  22  *   en -- ethernet
  23  *   wl -- wlan
  24  *   ww -- wwan
  25  *
  26  * types:
  27  *   o<index>                 -- on-board device index
  28  *   s<slot>f<function>       -- hotplug slot number
  29  *   x<MAC>                   -- MAC address
  30  *   p<bus>s<slot>f<function> -- PCI/physical location
  31  *
  32  * example:
  33  *   ID_NET_NAME_ONBOARD=eno1
  34  *   ID_NET_NAME_SLOT=ens1f0
  35  *   ID_NET_NAME_MAC=enxf0def180d479
  36  *   ID_NET_NAME_PATH=enp19s0f0
  37  */
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <stdarg.h>
  42 #include <unistd.h>
  43 #include <string.h>
  44 #include <errno.h>
  45
  46 #include "udev.h"
  47
  48 /* retrieve on-board index number and label from firmware */
  49 static int dev_pci_onboard(struct udev_device *dev, const char *prefix, bool test) {
  50         const char *index;
  51         int idx;
  52         const char *label;
  53         char s[16];
  54         int err;
  55
  56         /* ACPI _DSM  -- device specific method for naming a PCI or PCI Express device */
  57         index = udev_device_get_sysattr_value(dev, "acpi_index");
  58         /* SMBIOS type 41 -- Onboard Devices Extended Information */
  59         if (!index)
  60                 index = udev_device_get_sysattr_value(dev, "index");
  61         if (!index)
  62                 return -ENOENT;
  63         idx = strtoul(index, NULL, 0);
  64         if (idx <= 0)
  65                 return -EINVAL;
  66         snprintf(s, sizeof(s), "%so%d", prefix, idx);
  67         err = udev_builtin_add_property(dev, test, "ID_NET_NAME_ONBOARD", s);
  68         if (err < 0)
  69                 return err;
  70
  71         label = udev_device_get_sysattr_value(dev, "label");
  72         if (label) {
  73                 err = udev_builtin_add_property(dev, test, "ID_NET_LABEL_ONBOARD", label);
  74                 if (err < 0)
  75                         return err;
  76         }
  77         return 0;
  78 }
  79
  80 static int dev_pci_slot(struct udev_device *dev, const char *prefix, bool test) {
  81         struct udev *udev = udev_device_get_udev(dev);
  82         unsigned int bus;
  83         unsigned int slot;
  84         unsigned int func;
  85         struct udev_device *pci = NULL;
  86         char slots[256];
  87         DIR *dir;
  88         struct dirent *dent;
  89         char str[256];
  90         int hotplug_slot = 0;
  91         int err = 0;
  92
  93         /* compose a name based on the raw kernel's PCI bus, slot numbers */
  94         if (sscanf(udev_device_get_sysname(dev), "0000:%x:%x.%d", &bus, &slot, &func) != 3)
  95                 return -ENOENT;
  96         snprintf(str, sizeof(str), "%sp%ds%df%d", prefix, bus, slot, func);
  97         err = udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
  98         if (err < 0)
  99                 return err;
 100
 101         /* ACPI _SUN  -- slot user number */
 102         pci = udev_device_new_from_subsystem_sysname(udev, "subsystem", "pci");
 103         if (!pci) {
 104                 err = -ENOENT;
 105                 goto out;
 106         }
 107         snprintf(slots, sizeof(slots), "%s/slots", udev_device_get_syspath(pci));
 108         dir = opendir(slots);
 109         if (!dir) {
 110                 err = -errno;
 111                 goto out;
 112         }
 113
 114         for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
 115                 int i;
 116                 char *rest;
 117                 char *address;
 118
 119                 if (dent->d_name[0] == '.')
 120                         continue;
 121                 i = strtol(dent->d_name, &rest, 10);
 122                 if (rest[0] != '\0')
 123                         continue;
 124                 if (i < 1)
 125                         continue;
 126                 snprintf(str, sizeof(str), "%s/%s/address", slots, dent->d_name);
 127                 if (read_one_line_file(str, &address) >= 0) {
 128                         /* match slot address with device by stripping the function */
 129                         if (strncmp(address, udev_device_get_sysname(dev), strlen(address)) == 0)
 130                                 hotplug_slot = i;
 131                         free(address);
 132                 }
 133
 134                 if (hotplug_slot > 0)
 135                         break;
 136         }
 137         closedir(dir);
 138
 139         if (hotplug_slot > 0) {
 140                 snprintf(str, sizeof(str), "%ss%df%d", prefix, hotplug_slot, func);
 141                 err = udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 142         }
 143 out:
 144         udev_device_unref(pci);
 145         return err;
 146 }
 147
 148 static int dev_pci(struct udev_device *dev, const char *prefix, bool test) {
 149         struct udev_device *d;
 150
 151         /* skip other buses than direct PCI parents */
 152         d = udev_device_get_parent(dev);
 153         if (!d || !streq("pci", udev_device_get_subsystem(d)))
 154                 return -ENOENT;
 155
 156         dev_pci_onboard(d, prefix, test);
 157         dev_pci_slot(d, prefix, test);
 158         return 0;
 159 }
 160
 161 static int dev_mac(struct udev_device *dev, const char *prefix, bool test) {
 162         const char *s;
 163         unsigned int i;
 164         unsigned int a1, a2, a3, a4, a5, a6;
 165         char str[16];
 166
 167         /* check for NET_ADDR_PERM, skip random MAC addresses */
 168         s = udev_device_get_sysattr_value(dev, "addr_assign_type");
 169         if (!s)
 170                 return EXIT_FAILURE;
 171         i = strtoul(s, NULL, 0);
 172         if (i != 0)
 173                 return 0;
 174
 175         s = udev_device_get_sysattr_value(dev, "address");
 176         if (!s)
 177                 return -ENOENT;
 178         if (sscanf(s, "%x:%x:%x:%x:%x:%x", &a1, &a2, &a3, &a4, &a5, &a6) != 6)
 179                 return -EINVAL;
 180
 181         /* skip empty MAC addresses */
 182         if (a1 + a2 + a3 + a4 + a5 + a6 == 0)
 183                 return -EINVAL;
 184
 185         /* add IEEE Organizationally Unique Identifier */
 186         snprintf(str, sizeof(str), "OUI:%X%X%X", a1, a2, a3);
 187         udev_builtin_hwdb_lookup(dev, str, test);
 188
 189         snprintf(str, sizeof(str), "%sx%x%x%x%x%x%x", prefix, a1, a2, a3, a4, a5, a6);
 190         return udev_builtin_add_property(dev, test, "ID_NET_NAME_MAC", str);
 191 }
 192
 193 static int builtin_net_id(struct udev_device *dev, int argc, char *argv[], bool test) {
 194         const char *s;
 195         unsigned int i;
 196         const char *devtype;
 197         const char *prefix = "en";
 198
 199         /* handle only ARPHRD_ETHER devices */
 200         s = udev_device_get_sysattr_value(dev, "type");
 201         if (!s)
 202                 return EXIT_FAILURE;
 203         i = strtoul(s, NULL, 0);
 204         if (i != 1)
 205                 return 0;
 206
 207         devtype = udev_device_get_devtype(dev);
 208         if (devtype) {
 209                 if (streq("wlan", devtype))
 210                         prefix = "wl";
 211                 else if (streq("wwan", devtype))
 212                         prefix = "ww";
 213         }
 214
 215         dev_pci(dev, prefix, test);
 216         dev_mac(dev, prefix, test);
 217         return EXIT_SUCCESS;
 218 }
 219
 220 const struct udev_builtin udev_builtin_net_id = {
 221         .name = "net_id",
 222         .cmd = builtin_net_id,
 223         .help = "network device properties",
 224 };