src/udev/udev-builtin-net_id.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 /*
   4  * Predictable network interface device names based on:
   5  *  - firmware/bios-provided index numbers for on-board devices
   6  *  - firmware-provided pci-express hotplug slot index number
   7  *  - physical/geographical location of the hardware
   8  *  - the interface's MAC address
   9  *
  10  * http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames
  11  *
  12  * Two character prefixes based on the type of interface:
  13  *   en — Ethernet
  14  *   sl — serial line IP (slip)
  15  *   wl — wlan
  16  *   ww — wwan
  17  *
  18  * Type of names:
  19  *   b<number>                             — BCMA bus core number
  20  *   c<bus_id>                             — bus id of a grouped CCW or CCW device,
  21  *                                           with all leading zeros stripped [s390]
  22  *   o<index>[n<phys_port_name>|d<dev_port>]
  23  *                                         — on-board device index number
  24  *   s<slot>[f<function>][n<phys_port_name>|d<dev_port>]
  25  *                                         — hotplug slot index number
  26  *   x<MAC>                                — MAC address
  27  *   [P<domain>]p<bus>s<slot>[f<function>][n<phys_port_name>|d<dev_port>]
  28  *                                         — PCI geographical location
  29  *   [P<domain>]p<bus>s<slot>[f<function>][u<port>][..][c<config>][i<interface>]
  30  *                                         — USB port number chain
  31  *   v<slot>                               - VIO slot number (IBM PowerVM)
  32  *   a<vendor><model>i<instance>           — Platform bus ACPI instance id
  33  *
  34  * All multi-function PCI devices will carry the [f<function>] number in the
  35  * device name, including the function 0 device.
  36  *
  37  * SR-IOV virtual devices are named based on the name of the parent interface,
  38  * with a suffix of "v<N>", where <N> is the virtual device number.
  39  *
  40  * When using PCI geography, The PCI domain is only prepended when it is not 0.
  41  *
  42  * For USB devices the full chain of port numbers of hubs is composed. If the
  43  * name gets longer than the maximum number of 15 characters, the name is not
  44  * exported.
  45  * The usual USB configuration == 1 and interface == 0 values are suppressed.
  46  *
  47  * PCI Ethernet card with firmware index "1":
  48  *   ID_NET_NAME_ONBOARD=eno1
  49  *   ID_NET_NAME_ONBOARD_LABEL=Ethernet Port 1
  50  *
  51  * PCI Ethernet card in hotplug slot with firmware index number:
  52  *   /sys/devices/pci0000:00/0000:00:1c.3/0000:05:00.0/net/ens1
  53  *   ID_NET_NAME_MAC=enx000000000466
  54  *   ID_NET_NAME_PATH=enp5s0
  55  *   ID_NET_NAME_SLOT=ens1
  56  *
  57  * PCI Ethernet multi-function card with 2 ports:
  58  *   /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0/net/enp2s0f0
  59  *   ID_NET_NAME_MAC=enx78e7d1ea46da
  60  *   ID_NET_NAME_PATH=enp2s0f0
  61  *   /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.1/net/enp2s0f1
  62  *   ID_NET_NAME_MAC=enx78e7d1ea46dc
  63  *   ID_NET_NAME_PATH=enp2s0f1
  64  *
  65  * PCI wlan card:
  66  *   /sys/devices/pci0000:00/0000:00:1c.1/0000:03:00.0/net/wlp3s0
  67  *   ID_NET_NAME_MAC=wlx0024d7e31130
  68  *   ID_NET_NAME_PATH=wlp3s0
  69  *
  70  * USB built-in 3G modem:
  71  *   /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.4/2-1.4:1.6/net/wwp0s29u1u4i6
  72  *   ID_NET_NAME_MAC=wwx028037ec0200
  73  *   ID_NET_NAME_PATH=wwp0s29u1u4i6
  74  *
  75  * USB Android phone:
  76  *   /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/net/enp0s29u1u2
  77  *   ID_NET_NAME_MAC=enxd626b3450fb5
  78  *   ID_NET_NAME_PATH=enp0s29u1u2
  79  *
  80  * s390 grouped CCW interface:
  81  *  /sys/devices/css0/0.0.0007/0.0.f5f0/group_device/net/encf5f0
  82  *  ID_NET_NAME_MAC=enx026d3c00000a
  83  *  ID_NET_NAME_PATH=encf5f0
  84  */
  85
  86 #include <errno.h>
  87 #include <fcntl.h>
  88 #include <net/if.h>
  89 #include <net/if_arp.h>
  90 #include <stdarg.h>
  91 #include <stdio.h>
  92 #include <stdlib.h>
  93 #include <string.h>
  94 #include <unistd.h>
  95 #include <linux/pci_regs.h>
  96
  97 #include "dirent-util.h"
  98 #include "fd-util.h"
  99 #include "fileio.h"
 100 #include "fs-util.h"
 101 #include "parse-util.h"
 102 #include "stdio-util.h"
 103 #include "string-util.h"
 104 #include "udev.h"
 105 #include "udev-util.h"
 106
 107 #define ONBOARD_INDEX_MAX (16*1024-1)
 108
 109 enum netname_type{
 110         NET_UNDEF,
 111         NET_PCI,
 112         NET_USB,
 113         NET_BCMA,
 114         NET_VIRTIO,
 115         NET_CCW,
 116         NET_VIO,
 117         NET_PLATFORM,
 118 };
 119
 120 struct netnames {
 121         enum netname_type type;
 122
 123         uint8_t mac[6];
 124         bool mac_valid;
 125
 126         struct udev_device *pcidev;
 127         char pci_slot[IFNAMSIZ];
 128         char pci_path[IFNAMSIZ];
 129         char pci_onboard[IFNAMSIZ];
 130         const char *pci_onboard_label;
 131
 132         char usb_ports[IFNAMSIZ];
 133         char bcma_core[IFNAMSIZ];
 134         char ccw_busid[IFNAMSIZ];
 135         char vio_slot[IFNAMSIZ];
 136         char platform_path[IFNAMSIZ];
 137 };
 138
 139 struct virtfn_info {
 140         struct udev_device *physfn_pcidev;
 141         char suffix[IFNAMSIZ];
 142 };
 143
 144 /* skip intermediate virtio devices */
 145 static struct udev_device *skip_virtio(struct udev_device *dev) {
 146         struct udev_device *parent = dev;
 147
 148         /* there can only ever be one virtio bus per parent device, so we can
 149            safely ignore any virtio buses. see
 150            <http://lists.linuxfoundation.org/pipermail/virtualization/2015-August/030331.html> */
 151         while (parent && streq_ptr("virtio", udev_device_get_subsystem(parent)))
 152                 parent = udev_device_get_parent(parent);
 153         return parent;
 154 }
 155
 156 static int get_virtfn_info(struct udev_device *dev, struct netnames *names, struct virtfn_info *vf_info) {
 157         struct udev *udev;
 158         const char *physfn_link_file;
 159         _cleanup_free_ char *physfn_pci_syspath = NULL;
 160         _cleanup_free_ char *virtfn_pci_syspath = NULL;
 161         struct dirent *dent;
 162         _cleanup_closedir_ DIR *dir = NULL;
 163         struct virtfn_info vf_info_local = {};
 164         int r;
 165
 166         udev = udev_device_get_udev(names->pcidev);
 167         if (!udev)
 168                 return -ENOENT;
 169         /* Check if this is a virtual function. */
 170         physfn_link_file = strjoina(udev_device_get_syspath(names->pcidev), "/physfn");
 171         r = chase_symlinks(physfn_link_file, NULL, 0, &physfn_pci_syspath);
 172         if (r < 0)
 173                 return r;
 174
 175         /* Get physical function's pci device. */
 176         vf_info_local.physfn_pcidev = udev_device_new_from_syspath(udev, physfn_pci_syspath);
 177         if (!vf_info_local.physfn_pcidev)
 178                 return -ENOENT;
 179
 180         /* Find the virtual function number by finding the right virtfn link. */
 181         dir = opendir(physfn_pci_syspath);
 182         if (!dir) {
 183                 r = -errno;
 184                 goto out_unref;
 185         }
 186         FOREACH_DIRENT_ALL(dent, dir, break) {
 187                 _cleanup_free_ char *virtfn_link_file = NULL;
 188                 if (!startswith(dent->d_name, "virtfn"))
 189                         continue;
 190                 virtfn_link_file = strjoin(physfn_pci_syspath, "/", dent->d_name);
 191                 if (!virtfn_link_file) {
 192                         r = -ENOMEM;
 193                         goto out_unref;
 194                 }
 195                 if (chase_symlinks(virtfn_link_file, NULL, 0, &virtfn_pci_syspath) < 0)
 196                         continue;
 197                 if (streq(udev_device_get_syspath(names->pcidev), virtfn_pci_syspath)) {
 198                         if (!snprintf_ok(vf_info_local.suffix, sizeof(vf_info_local.suffix), "v%s", &dent->d_name[6])) {
 199                                 r = -ENOENT;
 200                                 goto out_unref;
 201                         }
 202                         break;
 203                 }
 204         }
 205         if (isempty(vf_info_local.suffix)) {
 206                 r = -ENOENT;
 207                 goto out_unref;
 208         }
 209         *vf_info = vf_info_local;
 210         return 0;
 211
 212 out_unref:
 213         udev_device_unref(vf_info_local.physfn_pcidev);
 214         return r;
 215 }
 216
 217 /* retrieve on-board index number and label from firmware */
 218 static int dev_pci_onboard(struct udev_device *dev, struct netnames *names) {
 219         unsigned dev_port = 0;
 220         size_t l;
 221         char *s;
 222         const char *attr, *port_name;
 223         int idx;
 224
 225         /* ACPI _DSM  — device specific method for naming a PCI or PCI Express device */
 226         attr = udev_device_get_sysattr_value(names->pcidev, "acpi_index");
 227         /* SMBIOS type 41 — Onboard Devices Extended Information */
 228         if (!attr)
 229                 attr = udev_device_get_sysattr_value(names->pcidev, "index");
 230         if (!attr)
 231                 return -ENOENT;
 232
 233         idx = strtoul(attr, NULL, 0);
 234         if (idx <= 0)
 235                 return -EINVAL;
 236
 237         /* Some BIOSes report rubbish indexes that are excessively high (2^24-1 is an index VMware likes to report for
 238          * example). Let's define a cut-off where we don't consider the index reliable anymore. We pick some arbitrary
 239          * cut-off, which is somewhere beyond the realistic number of physical network interface a system might
 240          * have. Ideally the kernel would already filter his crap for us, but it doesn't currently. */
 241         if (idx > ONBOARD_INDEX_MAX)
 242                 return -ENOENT;
 243
 244         /* kernel provided port index for multiple ports on a single PCI function */
 245         attr = udev_device_get_sysattr_value(dev, "dev_port");
 246         if (attr)
 247                 dev_port = strtol(attr, NULL, 10);
 248
 249         /* kernel provided front panel port name for multiple port PCI device */
 250         port_name = udev_device_get_sysattr_value(dev, "phys_port_name");
 251
 252         s = names->pci_onboard;
 253         l = sizeof(names->pci_onboard);
 254         l = strpcpyf(&s, l, "o%d", idx);
 255         if (port_name)
 256                 l = strpcpyf(&s, l, "n%s", port_name);
 257         else if (dev_port > 0)
 258                 l = strpcpyf(&s, l, "d%d", dev_port);
 259         if (l == 0)
 260                 names->pci_onboard[0] = '\0';
 261
 262         names->pci_onboard_label = udev_device_get_sysattr_value(names->pcidev, "label");
 263
 264         return 0;
 265 }
 266
 267 /* read the 256 bytes PCI configuration space to check the multi-function bit */
 268 static bool is_pci_multifunction(struct udev_device *dev) {
 269         _cleanup_close_ int fd = -1;
 270         const char *filename;
 271         uint8_t config[64];
 272
 273         filename = strjoina(udev_device_get_syspath(dev), "/config");
 274         fd = open(filename, O_RDONLY | O_CLOEXEC);
 275         if (fd < 0)
 276                 return false;
 277         if (read(fd, &config, sizeof(config)) != sizeof(config))
 278                 return false;
 279
 280         /* bit 0-6 header type, bit 7 multi/single function device */
 281         if ((config[PCI_HEADER_TYPE] & 0x80) != 0)
 282                 return true;
 283
 284         return false;
 285 }
 286
 287 static bool is_pci_ari_enabled(struct udev_device *dev) {
 288         return streq_ptr(udev_device_get_sysattr_value(dev, "ari_enabled"), "1");
 289 }
 290
 291 static int dev_pci_slot(struct udev_device *dev, struct netnames *names) {
 292         struct udev *udev = udev_device_get_udev(names->pcidev);
 293         unsigned domain, bus, slot, func, dev_port = 0, hotplug_slot = 0;
 294         size_t l;
 295         char *s;
 296         const char *attr, *port_name;
 297         _cleanup_(udev_device_unrefp) struct udev_device *pci = NULL;
 298         struct udev_device *hotplug_slot_dev;
 299         char slots[PATH_MAX];
 300         _cleanup_closedir_ DIR *dir = NULL;
 301         struct dirent *dent;
 302
 303         if (sscanf(udev_device_get_sysname(names->pcidev), "%x:%x:%x.%u", &domain, &bus, &slot, &func) != 4)
 304                 return -ENOENT;
 305         if (is_pci_ari_enabled(names->pcidev))
 306                 /* ARI devices support up to 256 functions on a single device ("slot"), and interpret the
 307                  * traditional 5-bit slot and 3-bit function number as a single 8-bit function number,
 308                  * where the slot makes up the upper 5 bits. */
 309                 func += slot * 8;
 310
 311         /* kernel provided port index for multiple ports on a single PCI function */
 312         attr = udev_device_get_sysattr_value(dev, "dev_port");
 313         if (attr)
 314                 dev_port = strtol(attr, NULL, 10);
 315
 316         /* kernel provided front panel port name for multiple port PCI device */
 317         port_name = udev_device_get_sysattr_value(dev, "phys_port_name");
 318
 319         /* compose a name based on the raw kernel's PCI bus, slot numbers */
 320         s = names->pci_path;
 321         l = sizeof(names->pci_path);
 322         if (domain > 0)
 323                 l = strpcpyf(&s, l, "P%u", domain);
 324         l = strpcpyf(&s, l, "p%us%u", bus, slot);
 325         if (func > 0 || is_pci_multifunction(names->pcidev))
 326                 l = strpcpyf(&s, l, "f%u", func);
 327         if (port_name)
 328                 l = strpcpyf(&s, l, "n%s", port_name);
 329         else if (dev_port > 0)
 330                 l = strpcpyf(&s, l, "d%u", dev_port);
 331         if (l == 0)
 332                 names->pci_path[0] = '\0';
 333
 334         /* ACPI _SUN  — slot user number */
 335         pci = udev_device_new_from_subsystem_sysname(udev, "subsystem", "pci");
 336         if (!pci)
 337                 return -ENOENT;
 338
 339         if (!snprintf_ok(slots, sizeof slots, "%s/slots", udev_device_get_syspath(pci)))
 340                 return -ENAMETOOLONG;
 341
 342         dir = opendir(slots);
 343         if (!dir)
 344                 return -errno;
 345
 346         hotplug_slot_dev = names->pcidev;
 347         while (hotplug_slot_dev) {
 348                 FOREACH_DIRENT_ALL(dent, dir, break) {
 349                         unsigned i;
 350                         int r;
 351                         char str[PATH_MAX];
 352                         _cleanup_free_ char *address = NULL;
 353
 354                         if (dent->d_name[0] == '.')
 355                                 continue;
 356                         r = safe_atou_full(dent->d_name, 10, &i);
 357                         if (i < 1 || r < 0)
 358                                 continue;
 359
 360                         if (snprintf_ok(str, sizeof str, "%s/%s/address", slots, dent->d_name) &&
 361                             read_one_line_file(str, &address) >= 0)
 362                                 /* match slot address with device by stripping the function */
 363                                 if (startswith(udev_device_get_sysname(hotplug_slot_dev), address))
 364                                         hotplug_slot = i;
 365
 366                         if (hotplug_slot > 0)
 367                                 break;
 368                 }
 369                 if (hotplug_slot > 0)
 370                         break;
 371                 rewinddir(dir);
 372                 hotplug_slot_dev = udev_device_get_parent_with_subsystem_devtype(hotplug_slot_dev, "pci", NULL);
 373         }
 374
 375         if (hotplug_slot > 0) {
 376                 s = names->pci_slot;
 377                 l = sizeof(names->pci_slot);
 378                 if (domain > 0)
 379                         l = strpcpyf(&s, l, "P%d", domain);
 380                 l = strpcpyf(&s, l, "s%d", hotplug_slot);
 381                 if (func > 0 || is_pci_multifunction(names->pcidev))
 382                         l = strpcpyf(&s, l, "f%d", func);
 383                 if (port_name)
 384                         l = strpcpyf(&s, l, "n%s", port_name);
 385                 else if (dev_port > 0)
 386                         l = strpcpyf(&s, l, "d%d", dev_port);
 387                 if (l == 0)
 388                         names->pci_slot[0] = '\0';
 389         }
 390
 391         return 0;
 392 }
 393
 394 static int names_vio(struct udev_device *dev, struct netnames *names) {
 395         struct udev_device *parent;
 396         unsigned busid, slotid, ethid;
 397         const char *syspath;
 398
 399         /* check if our direct parent is a VIO device with no other bus in-between */
 400         parent = udev_device_get_parent(dev);
 401         if (!parent)
 402                 return -ENOENT;
 403
 404         if (!streq_ptr("vio", udev_device_get_subsystem(parent)))
 405                  return -ENOENT;
 406
 407         /* The devices' $DEVPATH number is tied to (virtual) hardware (slot id
 408          * selected in the HMC), thus this provides a reliable naming (e.g.
 409          * "/devices/vio/30000002/net/eth1"); we ignore the bus number, as
 410          * there should only ever be one bus, and then remove leading zeros. */
 411         syspath = udev_device_get_syspath(dev);
 412
 413         if (sscanf(syspath, "/sys/devices/vio/%4x%4x/net/eth%u", &busid, &slotid, &ethid) != 3)
 414                 return -EINVAL;
 415
 416         xsprintf(names->vio_slot, "v%u", slotid);
 417         names->type = NET_VIO;
 418         return 0;
 419 }
 420
 421 #define _PLATFORM_TEST "/sys/devices/platform/vvvvPPPP"
 422 #define _PLATFORM_PATTERN4 "/sys/devices/platform/%4s%4x:%2x/net/eth%u"
 423 #define _PLATFORM_PATTERN3 "/sys/devices/platform/%3s%4x:%2x/net/eth%u"
 424
 425 static int names_platform(struct udev_device *dev, struct netnames *names, bool test) {
 426         struct udev_device *parent;
 427         char vendor[5];
 428         unsigned model, instance, ethid;
 429         const char *syspath, *pattern, *validchars;
 430
 431         /* check if our direct parent is a platform device with no other bus in-between */
 432         parent = udev_device_get_parent(dev);
 433         if (!parent)
 434                 return -ENOENT;
 435
 436         if (!streq_ptr("platform", udev_device_get_subsystem(parent)))
 437                  return -ENOENT;
 438
 439         syspath = udev_device_get_syspath(dev);
 440
 441         /* syspath is too short, to have a valid ACPI instance */
 442         if (strlen(syspath) < sizeof _PLATFORM_TEST)
 443                 return -EINVAL;
 444
 445         /* Vendor ID can be either PNP ID (3 chars A-Z) or ACPI ID (4 chars A-Z and numerals) */
 446         if (syspath[sizeof _PLATFORM_TEST - 1] == ':') {
 447                 pattern = _PLATFORM_PATTERN4;
 448                 validchars = UPPERCASE_LETTERS DIGITS;
 449         } else {
 450                 pattern = _PLATFORM_PATTERN3;
 451                 validchars = UPPERCASE_LETTERS;
 452         }
 453
 454         /* Platform devices are named after ACPI table match, and instance id
 455          * eg. "/sys/devices/platform/HISI00C2:00");
 456          * The Vendor (3 or 4 char), followed by hexdecimal model number : instance id.
 457          */
 458
 459 #pragma GCC diagnostic push
 460 #pragma GCC diagnostic ignored "-Wformat-nonliteral"
 461         if (sscanf(syspath, pattern, vendor, &model, &instance, &ethid) != 4)
 462                 return -EINVAL;
 463 #pragma GCC diagnostic pop
 464
 465         if (!in_charset(vendor, validchars))
 466                 return -ENOENT;
 467
 468         ascii_strlower(vendor);
 469
 470         xsprintf(names->platform_path, "a%s%xi%u", vendor, model, instance);
 471         names->type = NET_PLATFORM;
 472         return 0;
 473 }
 474
 475 static int names_pci(struct udev_device *dev, struct netnames *names) {
 476         struct udev_device *parent;
 477         struct netnames vf_names = {};
 478         struct virtfn_info vf_info = {};
 479
 480         assert(dev);
 481         assert(names);
 482
 483         parent = udev_device_get_parent(dev);
 484         /* skip virtio subsystem if present */
 485         parent = skip_virtio(parent);
 486
 487         if (!parent)
 488                 return -ENOENT;
 489
 490         /* check if our direct parent is a PCI device with no other bus in-between */
 491         if (streq_ptr("pci", udev_device_get_subsystem(parent))) {
 492                 names->type = NET_PCI;
 493                 names->pcidev = parent;
 494         } else {
 495                 names->pcidev = udev_device_get_parent_with_subsystem_devtype(dev, "pci", NULL);
 496                 if (!names->pcidev)
 497                         return -ENOENT;
 498         }
 499
 500         if (get_virtfn_info(dev, names, &vf_info) >= 0) {
 501                 /* If this is an SR-IOV virtual device, get base name using physical device and add virtfn suffix. */
 502                 vf_names.pcidev = vf_info.physfn_pcidev;
 503                 dev_pci_onboard(dev, &vf_names);
 504                 dev_pci_slot(dev, &vf_names);
 505                 if (vf_names.pci_onboard[0])
 506                         if (strlen(vf_names.pci_onboard) + strlen(vf_info.suffix) < sizeof(names->pci_onboard))
 507                                 strscpyl(names->pci_onboard, sizeof(names->pci_onboard),
 508                                          vf_names.pci_onboard, vf_info.suffix, NULL);
 509                 if (vf_names.pci_slot[0])
 510                         if (strlen(vf_names.pci_slot) + strlen(vf_info.suffix) < sizeof(names->pci_slot))
 511                                 strscpyl(names->pci_slot, sizeof(names->pci_slot),
 512                                          vf_names.pci_slot, vf_info.suffix, NULL);
 513                 if (vf_names.pci_path[0])
 514                         if (strlen(vf_names.pci_path) + strlen(vf_info.suffix) < sizeof(names->pci_path))
 515                                 strscpyl(names->pci_path, sizeof(names->pci_path),
 516                                          vf_names.pci_path, vf_info.suffix, NULL);
 517                 udev_device_unref(vf_info.physfn_pcidev);
 518         } else {
 519                 dev_pci_onboard(dev, names);
 520                 dev_pci_slot(dev, names);
 521         }
 522         return 0;
 523 }
 524
 525 static int names_usb(struct udev_device *dev, struct netnames *names) {
 526         struct udev_device *usbdev;
 527         char name[256];
 528         char *ports;
 529         char *config;
 530         char *interf;
 531         size_t l;
 532         char *s;
 533
 534         assert(dev);
 535         assert(names);
 536
 537         usbdev = udev_device_get_parent_with_subsystem_devtype(dev, "usb", "usb_interface");
 538         if (!usbdev)
 539                 return -ENOENT;
 540
 541         /* get USB port number chain, configuration, interface */
 542         strscpy(name, sizeof(name), udev_device_get_sysname(usbdev));
 543         s = strchr(name, '-');
 544         if (!s)
 545                 return -EINVAL;
 546         ports = s+1;
 547
 548         s = strchr(ports, ':');
 549         if (!s)
 550                 return -EINVAL;
 551         s[0] = '\0';
 552         config = s+1;
 553
 554         s = strchr(config, '.');
 555         if (!s)
 556                 return -EINVAL;
 557         s[0] = '\0';
 558         interf = s+1;
 559
 560         /* prefix every port number in the chain with "u" */
 561         s = ports;
 562         while ((s = strchr(s, '.')))
 563                 s[0] = 'u';
 564         s = names->usb_ports;
 565         l = strpcpyl(&s, sizeof(names->usb_ports), "u", ports, NULL);
 566
 567         /* append USB config number, suppress the common config == 1 */
 568         if (!streq(config, "1"))
 569                 l = strpcpyl(&s, sizeof(names->usb_ports), "c", config, NULL);
 570
 571         /* append USB interface number, suppress the interface == 0 */
 572         if (!streq(interf, "0"))
 573                 l = strpcpyl(&s, sizeof(names->usb_ports), "i", interf, NULL);
 574         if (l == 0)
 575                 return -ENAMETOOLONG;
 576
 577         names->type = NET_USB;
 578         return 0;
 579 }
 580
 581 static int names_bcma(struct udev_device *dev, struct netnames *names) {
 582         struct udev_device *bcmadev;
 583         unsigned int core;
 584
 585         assert(dev);
 586         assert(names);
 587
 588         bcmadev = udev_device_get_parent_with_subsystem_devtype(dev, "bcma", NULL);
 589         if (!bcmadev)
 590                 return -ENOENT;
 591
 592         /* bus num:core num */
 593         if (sscanf(udev_device_get_sysname(bcmadev), "bcma%*u:%u", &core) != 1)
 594                 return -EINVAL;
 595         /* suppress the common core == 0 */
 596         if (core > 0)
 597                 xsprintf(names->bcma_core, "b%u", core);
 598
 599         names->type = NET_BCMA;
 600         return 0;
 601 }
 602
 603 static int names_ccw(struct  udev_device *dev, struct netnames *names) {
 604         struct udev_device *cdev;
 605         const char *bus_id, *subsys;
 606         size_t bus_id_len;
 607         size_t bus_id_start;
 608
 609         assert(dev);
 610         assert(names);
 611
 612         /* Retrieve the associated CCW device */
 613         cdev = udev_device_get_parent(dev);
 614         /* skip virtio subsystem if present */
 615         cdev = skip_virtio(cdev);
 616         if (!cdev)
 617                 return -ENOENT;
 618
 619         /* Network devices are either single or grouped CCW devices */
 620         subsys = udev_device_get_subsystem(cdev);
 621         if (!STRPTR_IN_SET(subsys, "ccwgroup", "ccw"))
 622                 return -ENOENT;
 623
 624         /* Retrieve bus-ID of the CCW device.  The bus-ID uniquely
 625          * identifies the network device on the Linux on System z channel
 626          * subsystem.  Note that the bus-ID contains lowercase characters.
 627          */
 628         bus_id = udev_device_get_sysname(cdev);
 629         if (!bus_id)
 630                 return -ENOENT;
 631
 632         /* Check the length of the bus-ID.  Rely on that the kernel provides
 633          * a correct bus-ID; alternatively, improve this check and parse and
 634          * verify each bus-ID part...
 635          */
 636         bus_id_len = strlen(bus_id);
 637         if (!IN_SET(bus_id_len, 8, 9))
 638                 return -EINVAL;
 639
 640         /* Strip leading zeros from the bus id for aesthetic purposes. This
 641          * keeps the ccw names stable, yet much shorter in general case of
 642          * bus_id 0.0.0600 -> 600. This is similar to e.g. how PCI domain is
 643          * not prepended when it is zero. Preserve the last 0 for 0.0.0000.
 644          */
 645         bus_id_start = strspn(bus_id, ".0");
 646         bus_id += bus_id_start < bus_id_len ? bus_id_start : bus_id_len - 1;
 647
 648         /* Store the CCW bus-ID for use as network device name */
 649         if (snprintf_ok(names->ccw_busid, sizeof(names->ccw_busid), "c%s", bus_id))
 650                 names->type = NET_CCW;
 651
 652         return 0;
 653 }
 654
 655 static int names_mac(struct udev_device *dev, struct netnames *names) {
 656         const char *s;
 657         unsigned int i;
 658         unsigned int a1, a2, a3, a4, a5, a6;
 659
 660         /* check for NET_ADDR_PERM, skip random MAC addresses */
 661         s = udev_device_get_sysattr_value(dev, "addr_assign_type");
 662         if (!s)
 663                 return EXIT_FAILURE;
 664         i = strtoul(s, NULL, 0);
 665         if (i != 0)
 666                 return 0;
 667
 668         s = udev_device_get_sysattr_value(dev, "address");
 669         if (!s)
 670                 return -ENOENT;
 671         if (sscanf(s, "%x:%x:%x:%x:%x:%x", &a1, &a2, &a3, &a4, &a5, &a6) != 6)
 672                 return -EINVAL;
 673
 674         /* skip empty MAC addresses */
 675         if (a1 + a2 + a3 + a4 + a5 + a6 == 0)
 676                 return -EINVAL;
 677
 678         names->mac[0] = a1;
 679         names->mac[1] = a2;
 680         names->mac[2] = a3;
 681         names->mac[3] = a4;
 682         names->mac[4] = a5;
 683         names->mac[5] = a6;
 684         names->mac_valid = true;
 685         return 0;
 686 }
 687
 688 /* IEEE Organizationally Unique Identifier vendor string */
 689 static int ieee_oui(struct udev_device *dev, struct netnames *names, bool test) {
 690         char str[32];
 691
 692         if (!names->mac_valid)
 693                 return -ENOENT;
 694         /* skip commonly misused 00:00:00 (Xerox) prefix */
 695         if (memcmp(names->mac, "\0\0\0", 3) == 0)
 696                 return -EINVAL;
 697         xsprintf(str, "OUI:%02X%02X%02X%02X%02X%02X", names->mac[0],
 698                  names->mac[1], names->mac[2], names->mac[3], names->mac[4],
 699                  names->mac[5]);
 700         udev_builtin_hwdb_lookup(dev, NULL, str, NULL, test);
 701         return 0;
 702 }
 703
 704 static int builtin_net_id(struct udev_device *dev, int argc, char *argv[], bool test) {
 705         const char *s;
 706         const char *p;
 707         unsigned int i;
 708         const char *devtype;
 709         const char *prefix = "en";
 710         struct netnames names = {};
 711         int err;
 712
 713         /* handle only ARPHRD_ETHER and ARPHRD_SLIP devices */
 714         s = udev_device_get_sysattr_value(dev, "type");
 715         if (!s)
 716                 return EXIT_FAILURE;
 717         i = strtoul(s, NULL, 0);
 718         switch (i) {
 719         case ARPHRD_ETHER:
 720                 prefix = "en";
 721                 break;
 722         case ARPHRD_SLIP:
 723                 prefix = "sl";
 724                 break;
 725         default:
 726                 return 0;
 727         }
 728
 729         /* skip stacked devices, like VLANs, ... */
 730         s = udev_device_get_sysattr_value(dev, "ifindex");
 731         if (!s)
 732                 return EXIT_FAILURE;
 733         p = udev_device_get_sysattr_value(dev, "iflink");
 734         if (!p)
 735                 return EXIT_FAILURE;
 736         if (!streq(s, p))
 737                 return 0;
 738
 739         devtype = udev_device_get_devtype(dev);
 740         if (devtype) {
 741                 if (streq("wlan", devtype))
 742                         prefix = "wl";
 743                 else if (streq("wwan", devtype))
 744                         prefix = "ww";
 745         }
 746
 747         err = names_mac(dev, &names);
 748         if (err >= 0 && names.mac_valid) {
 749                 char str[IFNAMSIZ];
 750
 751                 xsprintf(str, "%sx%02x%02x%02x%02x%02x%02x", prefix,
 752                          names.mac[0], names.mac[1], names.mac[2],
 753                          names.mac[3], names.mac[4], names.mac[5]);
 754                 udev_builtin_add_property(dev, test, "ID_NET_NAME_MAC", str);
 755
 756                 ieee_oui(dev, &names, test);
 757         }
 758
 759         /* get path names for Linux on System z network devices */
 760         err = names_ccw(dev, &names);
 761         if (err >= 0 && names.type == NET_CCW) {
 762                 char str[IFNAMSIZ];
 763
 764                 if (snprintf_ok(str, sizeof str, "%s%s", prefix, names.ccw_busid))
 765                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 766                 goto out;
 767         }
 768
 769         /* get ibmveth/ibmvnic slot-based names. */
 770         err = names_vio(dev, &names);
 771         if (err >= 0 && names.type == NET_VIO) {
 772                 char str[IFNAMSIZ];
 773
 774                 if (snprintf_ok(str, sizeof str, "%s%s", prefix, names.vio_slot))
 775                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 776                 goto out;
 777         }
 778
 779         /* get ACPI path names for ARM64 platform devices */
 780         err = names_platform(dev, &names, test);
 781         if (err >= 0 && names.type == NET_PLATFORM) {
 782                 char str[IFNAMSIZ];
 783
 784                 if (snprintf_ok(str, sizeof str, "%s%s", prefix, names.platform_path))
 785                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 786                 goto out;
 787         }
 788
 789         /* get PCI based path names, we compose only PCI based paths */
 790         err = names_pci(dev, &names);
 791         if (err < 0)
 792                 goto out;
 793
 794         /* plain PCI device */
 795         if (names.type == NET_PCI) {
 796                 char str[IFNAMSIZ];
 797
 798                 if (names.pci_onboard[0] &&
 799                     snprintf_ok(str, sizeof str, "%s%s", prefix, names.pci_onboard))
 800                         udev_builtin_add_property(dev, test, "ID_NET_NAME_ONBOARD", str);
 801
 802                 if (names.pci_onboard_label &&
 803                     snprintf_ok(str, sizeof str, "%s%s", prefix, names.pci_onboard_label))
 804                         udev_builtin_add_property(dev, test, "ID_NET_LABEL_ONBOARD", str);
 805
 806                 if (names.pci_path[0] &&
 807                     snprintf_ok(str, sizeof str, "%s%s", prefix, names.pci_path))
 808                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 809
 810                 if (names.pci_slot[0] &&
 811                     snprintf_ok(str, sizeof str, "%s%s", prefix, names.pci_slot))
 812                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 813                 goto out;
 814         }
 815
 816         /* USB device */
 817         err = names_usb(dev, &names);
 818         if (err >= 0 && names.type == NET_USB) {
 819                 char str[IFNAMSIZ];
 820
 821                 if (names.pci_path[0] &&
 822                     snprintf_ok(str, sizeof str, "%s%s%s", prefix, names.pci_path, names.usb_ports))
 823                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 824
 825                 if (names.pci_slot[0] &&
 826                     snprintf_ok(str, sizeof str, "%s%s%s", prefix, names.pci_slot, names.usb_ports))
 827                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 828                 goto out;
 829         }
 830
 831         /* Broadcom bus */
 832         err = names_bcma(dev, &names);
 833         if (err >= 0 && names.type == NET_BCMA) {
 834                 char str[IFNAMSIZ];
 835
 836                 if (names.pci_path[0] &&
 837                     snprintf_ok(str, sizeof str, "%s%s%s", prefix, names.pci_path, names.bcma_core))
 838                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 839
 840                 if (names.pci_slot[0] &&
 841                     snprintf(str, sizeof str, "%s%s%s", prefix, names.pci_slot, names.bcma_core))
 842                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 843                 goto out;
 844         }
 845 out:
 846         return EXIT_SUCCESS;
 847 }
 848
 849 const struct udev_builtin udev_builtin_net_id = {
 850         .name = "net_id",
 851         .cmd = builtin_net_id,
 852         .help = "Network device properties",
 853 };