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  * When the code here is changed, man/systemd.net-naming-scheme.xml must be updated too.
  13  */
  14
  15 #include <errno.h>
  16 #include <fcntl.h>
  17 #include <net/if.h>
  18 #include <net/if_arp.h>
  19 #include <stdarg.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24 #include <linux/pci_regs.h>
  25
  26 #include "alloc-util.h"
  27 #include "dirent-util.h"
  28 #include "fd-util.h"
  29 #include "fileio.h"
  30 #include "fs-util.h"
  31 #include "naming-scheme.h"
  32 #include "parse-util.h"
  33 #include "proc-cmdline.h"
  34 #include "stdio-util.h"
  35 #include "string-util.h"
  36 #include "strv.h"
  37 #include "strxcpyx.h"
  38 #include "udev-builtin.h"
  39
  40 #define ONBOARD_INDEX_MAX (16*1024-1)
  41
  42 enum netname_type{
  43         NET_UNDEF,
  44         NET_PCI,
  45         NET_USB,
  46         NET_BCMA,
  47         NET_VIRTIO,
  48         NET_CCW,
  49         NET_VIO,
  50         NET_PLATFORM,
  51         NET_NETDEVSIM,
  52 };
  53
  54 struct netnames {
  55         enum netname_type type;
  56
  57         uint8_t mac[6];
  58         bool mac_valid;
  59
  60         sd_device *pcidev;
  61         char pci_slot[IFNAMSIZ];
  62         char pci_path[IFNAMSIZ];
  63         char pci_onboard[IFNAMSIZ];
  64         const char *pci_onboard_label;
  65
  66         char usb_ports[IFNAMSIZ];
  67         char bcma_core[IFNAMSIZ];
  68         char ccw_busid[IFNAMSIZ];
  69         char vio_slot[IFNAMSIZ];
  70         char platform_path[IFNAMSIZ];
  71         char netdevsim_path[IFNAMSIZ];
  72 };
  73
  74 struct virtfn_info {
  75         sd_device *physfn_pcidev;
  76         char suffix[IFNAMSIZ];
  77 };
  78
  79 /* skip intermediate virtio devices */
  80 static sd_device *skip_virtio(sd_device *dev) {
  81         sd_device *parent;
  82
  83         /* there can only ever be one virtio bus per parent device, so we can
  84          * safely ignore any virtio buses. see
  85          * http://lists.linuxfoundation.org/pipermail/virtualization/2015-August/030331.html */
  86         for (parent = dev; parent; ) {
  87                 const char *subsystem;
  88
  89                 if (sd_device_get_subsystem(parent, &subsystem) < 0)
  90                         break;
  91
  92                 if (!streq(subsystem, "virtio"))
  93                         break;
  94
  95                 if (sd_device_get_parent(parent, &parent) < 0)
  96                         return NULL;
  97         }
  98
  99         return parent;
 100 }
 101
 102 static int get_virtfn_info(sd_device *dev, struct netnames *names, struct virtfn_info *ret) {
 103         _cleanup_(sd_device_unrefp) sd_device *physfn_pcidev = NULL;
 104         const char *physfn_link_file, *syspath;
 105         _cleanup_free_ char *physfn_pci_syspath = NULL;
 106         _cleanup_free_ char *virtfn_pci_syspath = NULL;
 107         struct dirent *dent;
 108         _cleanup_closedir_ DIR *dir = NULL;
 109         char suffix[IFNAMSIZ];
 110         int r;
 111
 112         assert(dev);
 113         assert(names);
 114         assert(ret);
 115
 116         r = sd_device_get_syspath(names->pcidev, &syspath);
 117         if (r < 0)
 118                 return r;
 119
 120         /* Check if this is a virtual function. */
 121         physfn_link_file = strjoina(syspath, "/physfn");
 122         r = chase_symlinks(physfn_link_file, NULL, 0, &physfn_pci_syspath);
 123         if (r < 0)
 124                 return r;
 125
 126         /* Get physical function's pci device. */
 127         r = sd_device_new_from_syspath(&physfn_pcidev, physfn_pci_syspath);
 128         if (r < 0)
 129                 return r;
 130
 131         /* Find the virtual function number by finding the right virtfn link. */
 132         dir = opendir(physfn_pci_syspath);
 133         if (!dir)
 134                 return -errno;
 135
 136         FOREACH_DIRENT_ALL(dent, dir, break) {
 137                 _cleanup_free_ char *virtfn_link_file = NULL;
 138
 139                 if (!startswith(dent->d_name, "virtfn"))
 140                         continue;
 141
 142                 virtfn_link_file = strjoin(physfn_pci_syspath, "/", dent->d_name);
 143                 if (!virtfn_link_file)
 144                         return -ENOMEM;
 145
 146                 if (chase_symlinks(virtfn_link_file, NULL, 0, &virtfn_pci_syspath) < 0)
 147                         continue;
 148
 149                 if (streq(syspath, virtfn_pci_syspath)) {
 150                         if (!snprintf_ok(suffix, sizeof(suffix), "v%s", &dent->d_name[6]))
 151                                 return -ENOENT;
 152
 153                         break;
 154                 }
 155         }
 156         if (isempty(suffix))
 157                 return -ENOENT;
 158
 159         ret->physfn_pcidev = TAKE_PTR(physfn_pcidev);
 160         strncpy(ret->suffix, suffix, sizeof(ret->suffix));
 161
 162         return 0;
 163 }
 164
 165 /* retrieve on-board index number and label from firmware */
 166 static int dev_pci_onboard(sd_device *dev, struct netnames *names) {
 167         unsigned long idx, dev_port = 0;
 168         const char *attr, *port_name = NULL;
 169         size_t l;
 170         char *s;
 171         int r;
 172
 173         /* ACPI _DSM — device specific method for naming a PCI or PCI Express device */
 174         if (sd_device_get_sysattr_value(names->pcidev, "acpi_index", &attr) < 0) {
 175                 /* SMBIOS type 41 — Onboard Devices Extended Information */
 176                 r = sd_device_get_sysattr_value(names->pcidev, "index", &attr);
 177                 if (r < 0)
 178                         return r;
 179         }
 180
 181         r = safe_atolu(attr, &idx);
 182         if (r < 0)
 183                 return r;
 184         if (idx == 0 && !naming_scheme_has(NAMING_ZERO_ACPI_INDEX))
 185                 return -EINVAL;
 186
 187         /* Some BIOSes report rubbish indexes that are excessively high (2^24-1 is an index VMware likes to
 188          * report for example). Let's define a cut-off where we don't consider the index reliable anymore. We
 189          * pick some arbitrary cut-off, which is somewhere beyond the realistic number of physical network
 190          * interface a system might have. Ideally the kernel would already filter his crap for us, but it
 191          * doesn't currently. */
 192         if (idx > ONBOARD_INDEX_MAX)
 193                 return -ENOENT;
 194
 195         /* kernel provided port index for multiple ports on a single PCI function */
 196         if (sd_device_get_sysattr_value(dev, "dev_port", &attr) >= 0)
 197                 dev_port = strtoul(attr, NULL, 10);
 198
 199         /* kernel provided front panel port name for multiple port PCI device */
 200         (void) sd_device_get_sysattr_value(dev, "phys_port_name", &port_name);
 201
 202         s = names->pci_onboard;
 203         l = sizeof(names->pci_onboard);
 204         l = strpcpyf(&s, l, "o%lu", idx);
 205         if (port_name)
 206                 l = strpcpyf(&s, l, "n%s", port_name);
 207         else if (dev_port > 0)
 208                 l = strpcpyf(&s, l, "d%lu", dev_port);
 209         if (l == 0)
 210                 names->pci_onboard[0] = '\0';
 211
 212         if (sd_device_get_sysattr_value(names->pcidev, "label", &names->pci_onboard_label) < 0)
 213                 names->pci_onboard_label = NULL;
 214
 215         return 0;
 216 }
 217
 218 /* read the 256 bytes PCI configuration space to check the multi-function bit */
 219 static bool is_pci_multifunction(sd_device *dev) {
 220         _cleanup_close_ int fd = -1;
 221         const char *filename, *syspath;
 222         uint8_t config[64];
 223
 224         if (sd_device_get_syspath(dev, &syspath) < 0)
 225                 return false;
 226
 227         filename = strjoina(syspath, "/config");
 228         fd = open(filename, O_RDONLY | O_CLOEXEC);
 229         if (fd < 0)
 230                 return false;
 231         if (read(fd, &config, sizeof(config)) != sizeof(config))
 232                 return false;
 233
 234         /* bit 0-6 header type, bit 7 multi/single function device */
 235         return config[PCI_HEADER_TYPE] & 0x80;
 236 }
 237
 238 static bool is_pci_ari_enabled(sd_device *dev) {
 239         const char *a;
 240
 241         if (sd_device_get_sysattr_value(dev, "ari_enabled", &a) < 0)
 242                 return false;
 243
 244         return streq(a, "1");
 245 }
 246
 247 static int dev_pci_slot(sd_device *dev, struct netnames *names) {
 248         unsigned long dev_port = 0;
 249         unsigned domain, bus, slot, func, hotplug_slot = 0;
 250         size_t l;
 251         char *s;
 252         const char *sysname, *attr, *port_name = NULL, *syspath;
 253         _cleanup_(sd_device_unrefp) sd_device *pci = NULL;
 254         sd_device *hotplug_slot_dev;
 255         char slots[PATH_MAX];
 256         _cleanup_closedir_ DIR *dir = NULL;
 257         struct dirent *dent;
 258         int r;
 259
 260         r = sd_device_get_sysname(names->pcidev, &sysname);
 261         if (r < 0)
 262                 return r;
 263
 264         if (sscanf(sysname, "%x:%x:%x.%u", &domain, &bus, &slot, &func) != 4)
 265                 return -ENOENT;
 266
 267         if (naming_scheme_has(NAMING_NPAR_ARI) &&
 268             is_pci_ari_enabled(names->pcidev))
 269                 /* ARI devices support up to 256 functions on a single device ("slot"), and interpret the
 270                  * traditional 5-bit slot and 3-bit function number as a single 8-bit function number,
 271                  * where the slot makes up the upper 5 bits. */
 272                 func += slot * 8;
 273
 274         /* kernel provided port index for multiple ports on a single PCI function */
 275         if (sd_device_get_sysattr_value(dev, "dev_port", &attr) >= 0) {
 276                 dev_port = strtoul(attr, NULL, 10);
 277                 /* With older kernels IP-over-InfiniBand network interfaces sometimes erroneously
 278                  * provide the port number in the 'dev_id' sysfs attribute instead of 'dev_port',
 279                  * which thus stays initialized as 0. */
 280                 if (dev_port == 0 &&
 281                     sd_device_get_sysattr_value(dev, "type", &attr) >= 0) {
 282                         unsigned long type;
 283
 284                         type = strtoul(attr, NULL, 10);
 285                         if (type == ARPHRD_INFINIBAND &&
 286                             sd_device_get_sysattr_value(dev, "dev_id", &attr) >= 0)
 287                                 dev_port = strtoul(attr, NULL, 16);
 288                 }
 289         }
 290
 291         /* kernel provided front panel port name for multi-port PCI device */
 292         (void) sd_device_get_sysattr_value(dev, "phys_port_name", &port_name);
 293
 294         /* compose a name based on the raw kernel's PCI bus, slot numbers */
 295         s = names->pci_path;
 296         l = sizeof(names->pci_path);
 297         if (domain > 0)
 298                 l = strpcpyf(&s, l, "P%u", domain);
 299         l = strpcpyf(&s, l, "p%us%u", bus, slot);
 300         if (func > 0 || is_pci_multifunction(names->pcidev))
 301                 l = strpcpyf(&s, l, "f%u", func);
 302         if (port_name)
 303                 l = strpcpyf(&s, l, "n%s", port_name);
 304         else if (dev_port > 0)
 305                 l = strpcpyf(&s, l, "d%lu", dev_port);
 306         if (l == 0)
 307                 names->pci_path[0] = '\0';
 308
 309         /* ACPI _SUN — slot user number */
 310         r = sd_device_new_from_subsystem_sysname(&pci, "subsystem", "pci");
 311         if (r < 0)
 312                 return r;
 313
 314         r = sd_device_get_syspath(pci, &syspath);
 315         if (r < 0)
 316                 return r;
 317         if (!snprintf_ok(slots, sizeof slots, "%s/slots", syspath))
 318                 return -ENAMETOOLONG;
 319
 320         dir = opendir(slots);
 321         if (!dir)
 322                 return -errno;
 323
 324         hotplug_slot_dev = names->pcidev;
 325         while (hotplug_slot_dev) {
 326                 if (sd_device_get_sysname(hotplug_slot_dev, &sysname) < 0)
 327                         continue;
 328
 329                 FOREACH_DIRENT_ALL(dent, dir, break) {
 330                         unsigned i;
 331                         char str[PATH_MAX];
 332                         _cleanup_free_ char *address = NULL;
 333
 334                         if (dent->d_name[0] == '.')
 335                                 continue;
 336                         r = safe_atou_full(dent->d_name, 10, &i);
 337                         if (r < 0 || i <= 0)
 338                                 continue;
 339
 340                         /* match slot address with device by stripping the function */
 341                         if (snprintf_ok(str, sizeof str, "%s/%s/address", slots, dent->d_name) &&
 342                             read_one_line_file(str, &address) >= 0 &&
 343                             startswith(sysname, address)) {
 344                                 hotplug_slot = i;
 345                                 break;
 346                         }
 347                 }
 348                 if (hotplug_slot > 0)
 349                         break;
 350                 if (sd_device_get_parent_with_subsystem_devtype(hotplug_slot_dev, "pci", NULL, &hotplug_slot_dev) < 0)
 351                         break;
 352                 rewinddir(dir);
 353         }
 354
 355         if (hotplug_slot > 0) {
 356                 s = names->pci_slot;
 357                 l = sizeof(names->pci_slot);
 358                 if (domain > 0)
 359                         l = strpcpyf(&s, l, "P%d", domain);
 360                 l = strpcpyf(&s, l, "s%d", hotplug_slot);
 361                 if (func > 0 || is_pci_multifunction(names->pcidev))
 362                         l = strpcpyf(&s, l, "f%d", func);
 363                 if (port_name)
 364                         l = strpcpyf(&s, l, "n%s", port_name);
 365                 else if (dev_port > 0)
 366                         l = strpcpyf(&s, l, "d%lu", dev_port);
 367                 if (l == 0)
 368                         names->pci_slot[0] = '\0';
 369         }
 370
 371         return 0;
 372 }
 373
 374 static int names_vio(sd_device *dev, struct netnames *names) {
 375         sd_device *parent;
 376         unsigned busid, slotid, ethid;
 377         const char *syspath, *subsystem;
 378         int r;
 379
 380         /* check if our direct parent is a VIO device with no other bus in-between */
 381         r = sd_device_get_parent(dev, &parent);
 382         if (r < 0)
 383                 return r;
 384
 385         r = sd_device_get_subsystem(parent, &subsystem);
 386         if (r < 0)
 387                 return r;
 388         if (!streq("vio", subsystem))
 389                 return -ENOENT;
 390
 391         /* The devices' $DEVPATH number is tied to (virtual) hardware (slot id
 392          * selected in the HMC), thus this provides a reliable naming (e.g.
 393          * "/devices/vio/30000002/net/eth1"); we ignore the bus number, as
 394          * there should only ever be one bus, and then remove leading zeros. */
 395         r = sd_device_get_syspath(dev, &syspath);
 396         if (r < 0)
 397                 return r;
 398
 399         if (sscanf(syspath, "/sys/devices/vio/%4x%4x/net/eth%u", &busid, &slotid, &ethid) != 3)
 400                 return -EINVAL;
 401
 402         xsprintf(names->vio_slot, "v%u", slotid);
 403         names->type = NET_VIO;
 404         return 0;
 405 }
 406
 407 #define _PLATFORM_TEST "/sys/devices/platform/vvvvPPPP"
 408 #define _PLATFORM_PATTERN4 "/sys/devices/platform/%4s%4x:%2x/net/eth%u"
 409 #define _PLATFORM_PATTERN3 "/sys/devices/platform/%3s%4x:%2x/net/eth%u"
 410
 411 static int names_platform(sd_device *dev, struct netnames *names, bool test) {
 412         sd_device *parent;
 413         char vendor[5];
 414         unsigned model, instance, ethid;
 415         const char *syspath, *pattern, *validchars, *subsystem;
 416         int r;
 417
 418         /* check if our direct parent is a platform device with no other bus in-between */
 419         r = sd_device_get_parent(dev, &parent);
 420         if (r < 0)
 421                 return r;
 422
 423         r = sd_device_get_subsystem(parent, &subsystem);
 424         if (r < 0)
 425                 return r;
 426
 427         if (!streq("platform", subsystem))
 428                  return -ENOENT;
 429
 430         r = sd_device_get_syspath(dev, &syspath);
 431         if (r < 0)
 432                 return r;
 433
 434         /* syspath is too short, to have a valid ACPI instance */
 435         if (strlen(syspath) < sizeof _PLATFORM_TEST)
 436                 return -EINVAL;
 437
 438         /* Vendor ID can be either PNP ID (3 chars A-Z) or ACPI ID (4 chars A-Z and numerals) */
 439         if (syspath[sizeof _PLATFORM_TEST - 1] == ':') {
 440                 pattern = _PLATFORM_PATTERN4;
 441                 validchars = UPPERCASE_LETTERS DIGITS;
 442         } else {
 443                 pattern = _PLATFORM_PATTERN3;
 444                 validchars = UPPERCASE_LETTERS;
 445         }
 446
 447         /* Platform devices are named after ACPI table match, and instance id
 448          * eg. "/sys/devices/platform/HISI00C2:00");
 449          * The Vendor (3 or 4 char), followed by hexdecimal model number : instance id.
 450          */
 451
 452 #pragma GCC diagnostic push
 453 #pragma GCC diagnostic ignored "-Wformat-nonliteral"
 454         if (sscanf(syspath, pattern, vendor, &model, &instance, &ethid) != 4)
 455                 return -EINVAL;
 456 #pragma GCC diagnostic pop
 457
 458         if (!in_charset(vendor, validchars))
 459                 return -ENOENT;
 460
 461         ascii_strlower(vendor);
 462
 463         xsprintf(names->platform_path, "a%s%xi%u", vendor, model, instance);
 464         names->type = NET_PLATFORM;
 465         return 0;
 466 }
 467
 468 static int names_pci(sd_device *dev, struct netnames *names) {
 469         sd_device *parent;
 470         struct netnames vf_names = {};
 471         struct virtfn_info vf_info = {};
 472         const char *subsystem;
 473         int r;
 474
 475         assert(dev);
 476         assert(names);
 477
 478         r = sd_device_get_parent(dev, &parent);
 479         if (r < 0)
 480                 return r;
 481         /* skip virtio subsystem if present */
 482         parent = skip_virtio(parent);
 483
 484         if (!parent)
 485                 return -ENOENT;
 486
 487         /* check if our direct parent is a PCI device with no other bus in-between */
 488         if (sd_device_get_subsystem(parent, &subsystem) >= 0 &&
 489             streq("pci", subsystem)) {
 490                 names->type = NET_PCI;
 491                 names->pcidev = parent;
 492         } else {
 493                 r = sd_device_get_parent_with_subsystem_devtype(dev, "pci", NULL, &names->pcidev);
 494                 if (r < 0)
 495                         return r;
 496         }
 497
 498         if (naming_scheme_has(NAMING_SR_IOV_V) &&
 499             get_virtfn_info(dev, names, &vf_info) >= 0) {
 500                 /* If this is an SR-IOV virtual device, get base name using physical device and add virtfn suffix. */
 501                 vf_names.pcidev = vf_info.physfn_pcidev;
 502                 dev_pci_onboard(dev, &vf_names);
 503                 dev_pci_slot(dev, &vf_names);
 504                 if (vf_names.pci_onboard[0])
 505                         if (strlen(vf_names.pci_onboard) + strlen(vf_info.suffix) < sizeof(names->pci_onboard))
 506                                 strscpyl(names->pci_onboard, sizeof(names->pci_onboard),
 507                                          vf_names.pci_onboard, vf_info.suffix, NULL);
 508                 if (vf_names.pci_slot[0])
 509                         if (strlen(vf_names.pci_slot) + strlen(vf_info.suffix) < sizeof(names->pci_slot))
 510                                 strscpyl(names->pci_slot, sizeof(names->pci_slot),
 511                                          vf_names.pci_slot, vf_info.suffix, NULL);
 512                 if (vf_names.pci_path[0])
 513                         if (strlen(vf_names.pci_path) + strlen(vf_info.suffix) < sizeof(names->pci_path))
 514                                 strscpyl(names->pci_path, sizeof(names->pci_path),
 515                                          vf_names.pci_path, vf_info.suffix, NULL);
 516                 sd_device_unref(vf_info.physfn_pcidev);
 517         } else {
 518                 dev_pci_onboard(dev, names);
 519                 dev_pci_slot(dev, names);
 520         }
 521
 522         return 0;
 523 }
 524
 525 static int names_usb(sd_device *dev, struct netnames *names) {
 526         sd_device *usbdev;
 527         char name[256], *ports, *config, *interf, *s;
 528         const char *sysname;
 529         size_t l;
 530         int r;
 531
 532         assert(dev);
 533         assert(names);
 534
 535         r = sd_device_get_parent_with_subsystem_devtype(dev, "usb", "usb_interface", &usbdev);
 536         if (r < 0)
 537                 return r;
 538
 539         r = sd_device_get_sysname(usbdev, &sysname);
 540         if (r < 0)
 541                 return r;
 542
 543         /* get USB port number chain, configuration, interface */
 544         strscpy(name, sizeof(name), sysname);
 545         s = strchr(name, '-');
 546         if (!s)
 547                 return -EINVAL;
 548         ports = s+1;
 549
 550         s = strchr(ports, ':');
 551         if (!s)
 552                 return -EINVAL;
 553         s[0] = '\0';
 554         config = s+1;
 555
 556         s = strchr(config, '.');
 557         if (!s)
 558                 return -EINVAL;
 559         s[0] = '\0';
 560         interf = s+1;
 561
 562         /* prefix every port number in the chain with "u" */
 563         s = ports;
 564         while ((s = strchr(s, '.')))
 565                 s[0] = 'u';
 566         s = names->usb_ports;
 567         l = strpcpyl(&s, sizeof(names->usb_ports), "u", ports, NULL);
 568
 569         /* append USB config number, suppress the common config == 1 */
 570         if (!streq(config, "1"))
 571                 l = strpcpyl(&s, sizeof(names->usb_ports), "c", config, NULL);
 572
 573         /* append USB interface number, suppress the interface == 0 */
 574         if (!streq(interf, "0"))
 575                 l = strpcpyl(&s, sizeof(names->usb_ports), "i", interf, NULL);
 576         if (l == 0)
 577                 return -ENAMETOOLONG;
 578
 579         names->type = NET_USB;
 580         return 0;
 581 }
 582
 583 static int names_bcma(sd_device *dev, struct netnames *names) {
 584         sd_device *bcmadev;
 585         unsigned core;
 586         const char *sysname;
 587         int r;
 588
 589         assert(dev);
 590         assert(names);
 591
 592         r = sd_device_get_parent_with_subsystem_devtype(dev, "bcma", NULL, &bcmadev);
 593         if (r < 0)
 594                 return r;
 595
 596         r = sd_device_get_sysname(bcmadev, &sysname);
 597         if (r < 0)
 598                 return r;
 599
 600         /* bus num:core num */
 601         if (sscanf(sysname, "bcma%*u:%u", &core) != 1)
 602                 return -EINVAL;
 603         /* suppress the common core == 0 */
 604         if (core > 0)
 605                 xsprintf(names->bcma_core, "b%u", core);
 606
 607         names->type = NET_BCMA;
 608         return 0;
 609 }
 610
 611 static int names_ccw(sd_device *dev, struct netnames *names) {
 612         sd_device *cdev;
 613         const char *bus_id, *subsys;
 614         size_t bus_id_len;
 615         size_t bus_id_start;
 616         int r;
 617
 618         assert(dev);
 619         assert(names);
 620
 621         /* Retrieve the associated CCW device */
 622         r = sd_device_get_parent(dev, &cdev);
 623         if (r < 0)
 624                 return r;
 625
 626         /* skip virtio subsystem if present */
 627         cdev = skip_virtio(cdev);
 628         if (!cdev)
 629                 return -ENOENT;
 630
 631         r = sd_device_get_subsystem(cdev, &subsys);
 632         if (r < 0)
 633                 return r;
 634
 635         /* Network devices are either single or grouped CCW devices */
 636         if (!STR_IN_SET(subsys, "ccwgroup", "ccw"))
 637                 return -ENOENT;
 638
 639         /* Retrieve bus-ID of the CCW device.  The bus-ID uniquely
 640          * identifies the network device on the Linux on System z channel
 641          * subsystem.  Note that the bus-ID contains lowercase characters.
 642          */
 643         r = sd_device_get_sysname(cdev, &bus_id);
 644         if (r < 0)
 645                 return r;
 646
 647         /* Check the length of the bus-ID. Rely on the fact that the kernel provides a correct bus-ID;
 648          * alternatively, improve this check and parse and verify each bus-ID part...
 649          */
 650         bus_id_len = strlen(bus_id);
 651         if (!IN_SET(bus_id_len, 8, 9))
 652                 return -EINVAL;
 653
 654         /* Strip leading zeros from the bus id for aesthetic purposes. This
 655          * keeps the ccw names stable, yet much shorter in general case of
 656          * bus_id 0.0.0600 -> 600. This is similar to e.g. how PCI domain is
 657          * not prepended when it is zero. Preserve the last 0 for 0.0.0000.
 658          */
 659         bus_id_start = strspn(bus_id, ".0");
 660         bus_id += bus_id_start < bus_id_len ? bus_id_start : bus_id_len - 1;
 661
 662         /* Store the CCW bus-ID for use as network device name */
 663         if (snprintf_ok(names->ccw_busid, sizeof(names->ccw_busid), "c%s", bus_id))
 664                 names->type = NET_CCW;
 665
 666         return 0;
 667 }
 668
 669 static int names_mac(sd_device *dev, struct netnames *names) {
 670         const char *s;
 671         unsigned long i;
 672         unsigned a1, a2, a3, a4, a5, a6;
 673         int r;
 674
 675         /* Some kinds of devices tend to have hardware addresses
 676          * that are impossible to use in an iface name.
 677          */
 678         r = sd_device_get_sysattr_value(dev, "type", &s);
 679         if (r < 0)
 680                 return r;
 681
 682         i = strtoul(s, NULL, 0);
 683         switch (i) {
 684         /* The persistent part of a hardware address of an InfiniBand NIC
 685          * is 8 bytes long. We cannot fit this much in an iface name.
 686          */
 687         case ARPHRD_INFINIBAND:
 688                 return -EINVAL;
 689         default:
 690                 break;
 691         }
 692
 693         /* check for NET_ADDR_PERM, skip random MAC addresses */
 694         r = sd_device_get_sysattr_value(dev, "addr_assign_type", &s);
 695         if (r < 0)
 696                 return r;
 697         i = strtoul(s, NULL, 0);
 698         if (i != 0)
 699                 return 0;
 700
 701         r = sd_device_get_sysattr_value(dev, "address", &s);
 702         if (r < 0)
 703                 return r;
 704         if (sscanf(s, "%x:%x:%x:%x:%x:%x", &a1, &a2, &a3, &a4, &a5, &a6) != 6)
 705                 return -EINVAL;
 706
 707         /* skip empty MAC addresses */
 708         if (a1 + a2 + a3 + a4 + a5 + a6 == 0)
 709                 return -EINVAL;
 710
 711         names->mac[0] = a1;
 712         names->mac[1] = a2;
 713         names->mac[2] = a3;
 714         names->mac[3] = a4;
 715         names->mac[4] = a5;
 716         names->mac[5] = a6;
 717         names->mac_valid = true;
 718         return 0;
 719 }
 720
 721 static int names_netdevsim(sd_device *dev, struct netnames *names) {
 722         sd_device *netdevsimdev;
 723         const char *sysname;
 724         unsigned addr;
 725         const char *port_name = NULL;
 726         int r;
 727         bool ok;
 728
 729         if (!naming_scheme_has(NAMING_NETDEVSIM))
 730                 return 0;
 731
 732         assert(dev);
 733         assert(names);
 734
 735         r = sd_device_get_parent_with_subsystem_devtype(dev, "netdevsim", NULL, &netdevsimdev);
 736         if (r < 0)
 737                 return r;
 738         r = sd_device_get_sysname(netdevsimdev, &sysname);
 739         if (r < 0)
 740                 return r;
 741
 742         if (sscanf(sysname, "netdevsim%u", &addr) != 1)
 743                 return -EINVAL;
 744
 745         r = sd_device_get_sysattr_value(dev, "phys_port_name", &port_name);
 746         if (r < 0)
 747                 return r;
 748
 749         ok = snprintf_ok(names->netdevsim_path, sizeof(names->netdevsim_path), "i%un%s", addr, port_name);
 750         if (!ok)
 751                 return -ENOBUFS;
 752
 753         names->type = NET_NETDEVSIM;
 754
 755         return 0;
 756 }
 757
 758 /* IEEE Organizationally Unique Identifier vendor string */
 759 static int ieee_oui(sd_device *dev, struct netnames *names, bool test) {
 760         char str[32];
 761
 762         if (!names->mac_valid)
 763                 return -ENOENT;
 764         /* skip commonly misused 00:00:00 (Xerox) prefix */
 765         if (memcmp(names->mac, "\0\0\0", 3) == 0)
 766                 return -EINVAL;
 767         xsprintf(str, "OUI:%02X%02X%02X%02X%02X%02X", names->mac[0],
 768                  names->mac[1], names->mac[2], names->mac[3], names->mac[4],
 769                  names->mac[5]);
 770         udev_builtin_hwdb_lookup(dev, NULL, str, NULL, test);
 771         return 0;
 772 }
 773
 774 static int builtin_net_id(sd_device *dev, int argc, char *argv[], bool test) {
 775         const char *s, *p, *devtype, *prefix = "en";
 776         struct netnames names = {};
 777         unsigned long i;
 778         int r;
 779
 780         /* handle only ARPHRD_ETHER, ARPHRD_SLIP and ARPHRD_INFINIBAND devices */
 781         r = sd_device_get_sysattr_value(dev, "type", &s);
 782         if (r < 0)
 783                 return r;
 784
 785         i = strtoul(s, NULL, 0);
 786         switch (i) {
 787         case ARPHRD_ETHER:
 788                 prefix = "en";
 789                 break;
 790         case ARPHRD_INFINIBAND:
 791                 if (naming_scheme_has(NAMING_INFINIBAND))
 792                         prefix = "ib";
 793                 else
 794                         return 0;
 795                 break;
 796         case ARPHRD_SLIP:
 797                 prefix = "sl";
 798                 break;
 799         default:
 800                 return 0;
 801         }
 802
 803         /* skip stacked devices, like VLANs, ... */
 804         r = sd_device_get_sysattr_value(dev, "ifindex", &s);
 805         if (r < 0)
 806                 return r;
 807         r = sd_device_get_sysattr_value(dev, "iflink", &p);
 808         if (r < 0)
 809                 return r;
 810         if (!streq(s, p))
 811                 return 0;
 812
 813         if (sd_device_get_devtype(dev, &devtype) >= 0) {
 814                 if (streq("wlan", devtype))
 815                         prefix = "wl";
 816                 else if (streq("wwan", devtype))
 817                         prefix = "ww";
 818         }
 819
 820         udev_builtin_add_property(dev, test, "ID_NET_NAMING_SCHEME", naming_scheme()->name);
 821
 822         r = names_mac(dev, &names);
 823         if (r >= 0 && names.mac_valid) {
 824                 char str[IFNAMSIZ];
 825
 826                 xsprintf(str, "%sx%02x%02x%02x%02x%02x%02x", prefix,
 827                          names.mac[0], names.mac[1], names.mac[2],
 828                          names.mac[3], names.mac[4], names.mac[5]);
 829                 udev_builtin_add_property(dev, test, "ID_NET_NAME_MAC", str);
 830
 831                 ieee_oui(dev, &names, test);
 832         }
 833
 834         /* get path names for Linux on System z network devices */
 835         if (names_ccw(dev, &names) >= 0 && names.type == NET_CCW) {
 836                 char str[IFNAMSIZ];
 837
 838                 if (snprintf_ok(str, sizeof str, "%s%s", prefix, names.ccw_busid))
 839                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 840                 return 0;
 841         }
 842
 843         /* get ibmveth/ibmvnic slot-based names. */
 844         if (names_vio(dev, &names) >= 0 && names.type == NET_VIO) {
 845                 char str[IFNAMSIZ];
 846
 847                 if (snprintf_ok(str, sizeof str, "%s%s", prefix, names.vio_slot))
 848                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 849                 return 0;
 850         }
 851
 852         /* get ACPI path names for ARM64 platform devices */
 853         if (names_platform(dev, &names, test) >= 0 && names.type == NET_PLATFORM) {
 854                 char str[IFNAMSIZ];
 855
 856                 if (snprintf_ok(str, sizeof str, "%s%s", prefix, names.platform_path))
 857                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 858                 return 0;
 859         }
 860
 861         /* get netdevsim path names */
 862         if (names_netdevsim(dev, &names) >= 0 && names.type == NET_NETDEVSIM) {
 863                 char str[IFNAMSIZ];
 864
 865                 if (snprintf_ok(str, sizeof str, "%s%s", prefix, names.netdevsim_path))
 866                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 867
 868                 return 0;
 869         }
 870
 871         /* get PCI based path names, we compose only PCI based paths */
 872         if (names_pci(dev, &names) < 0)
 873                 return 0;
 874
 875         /* plain PCI device */
 876         if (names.type == NET_PCI) {
 877                 char str[IFNAMSIZ];
 878
 879                 if (names.pci_onboard[0] &&
 880                     snprintf_ok(str, sizeof str, "%s%s", prefix, names.pci_onboard))
 881                         udev_builtin_add_property(dev, test, "ID_NET_NAME_ONBOARD", str);
 882
 883                 if (names.pci_onboard_label &&
 884                     snprintf_ok(str, sizeof str, "%s%s",
 885                                 naming_scheme_has(NAMING_LABEL_NOPREFIX) ? "" : prefix,
 886                                 names.pci_onboard_label))
 887                         udev_builtin_add_property(dev, test, "ID_NET_LABEL_ONBOARD", str);
 888
 889                 if (names.pci_path[0] &&
 890                     snprintf_ok(str, sizeof str, "%s%s", prefix, names.pci_path))
 891                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 892
 893                 if (names.pci_slot[0] &&
 894                     snprintf_ok(str, sizeof str, "%s%s", prefix, names.pci_slot))
 895                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 896                 return 0;
 897         }
 898
 899         /* USB device */
 900         if (names_usb(dev, &names) >= 0 && names.type == NET_USB) {
 901                 char str[IFNAMSIZ];
 902
 903                 if (names.pci_path[0] &&
 904                     snprintf_ok(str, sizeof str, "%s%s%s", prefix, names.pci_path, names.usb_ports))
 905                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 906
 907                 if (names.pci_slot[0] &&
 908                     snprintf_ok(str, sizeof str, "%s%s%s", prefix, names.pci_slot, names.usb_ports))
 909                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 910                 return 0;
 911         }
 912
 913         /* Broadcom bus */
 914         if (names_bcma(dev, &names) >= 0 && names.type == NET_BCMA) {
 915                 char str[IFNAMSIZ];
 916
 917                 if (names.pci_path[0] &&
 918                     snprintf_ok(str, sizeof str, "%s%s%s", prefix, names.pci_path, names.bcma_core))
 919                         udev_builtin_add_property(dev, test, "ID_NET_NAME_PATH", str);
 920
 921                 if (names.pci_slot[0] &&
 922                     snprintf(str, sizeof str, "%s%s%s", prefix, names.pci_slot, names.bcma_core))
 923                         udev_builtin_add_property(dev, test, "ID_NET_NAME_SLOT", str);
 924                 return 0;
 925         }
 926
 927         return 0;
 928 }
 929
 930 const struct udev_builtin udev_builtin_net_id = {
 931         .name = "net_id",
 932         .cmd = builtin_net_id,
 933         .help = "Network device properties",
 934 };