zebra/zebra_pw.c

   1 /* Zebra PW code
   2  * Copyright (C) 2016 Volta Networks, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; see the file COPYING; if not, write to the
  16  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  17  * MA 02110-1301 USA
  18  */
  19
  20 #include <zebra.h>
  21
  22 #include "log.h"
  23 #include "memory.h"
  24 #include "thread.h"
  25 #include "command.h"
  26 #include "vrf.h"
  27
  28 #include "zebra/debug.h"
  29 #include "zebra/rib.h"
  30 #include "zebra/zebra_router.h"
  31 #include "zebra/zapi_msg.h"
  32 #include "zebra/zebra_rnh.h"
  33 #include "zebra/zebra_vrf.h"
  34 #include "zebra/zebra_pw.h"
  35
  36 DEFINE_MTYPE_STATIC(LIB, PW, "Pseudowire")
  37
  38 DEFINE_QOBJ_TYPE(zebra_pw)
  39
  40 DEFINE_HOOK(pw_install, (struct zebra_pw * pw), (pw))
  41 DEFINE_HOOK(pw_uninstall, (struct zebra_pw * pw), (pw))
  42
  43 #define MPLS_NO_LABEL MPLS_INVALID_LABEL
  44
  45 static int zebra_pw_enabled(struct zebra_pw *);
  46 static void zebra_pw_install(struct zebra_pw *);
  47 static void zebra_pw_uninstall(struct zebra_pw *);
  48 static int zebra_pw_install_retry(struct thread *);
  49 static int zebra_pw_check_reachability(struct zebra_pw *);
  50 static void zebra_pw_update_status(struct zebra_pw *, int);
  51
  52 static inline int zebra_pw_compare(const struct zebra_pw *a,
  53                                    const struct zebra_pw *b)
  54 {
  55         return (strcmp(a->ifname, b->ifname));
  56 }
  57
  58 RB_GENERATE(zebra_pw_head, zebra_pw, pw_entry, zebra_pw_compare)
  59 RB_GENERATE(zebra_static_pw_head, zebra_pw, static_pw_entry, zebra_pw_compare)
  60
  61 struct zebra_pw *zebra_pw_add(struct zebra_vrf *zvrf, const char *ifname,
  62                               uint8_t protocol, struct zserv *client)
  63 {
  64         struct zebra_pw *pw;
  65
  66         if (IS_ZEBRA_DEBUG_PW)
  67                 zlog_debug("%u: adding pseudowire %s protocol %s",
  68                            zvrf_id(zvrf), ifname, zebra_route_string(protocol));
  69
  70         pw = XCALLOC(MTYPE_PW, sizeof(*pw));
  71         strlcpy(pw->ifname, ifname, sizeof(pw->ifname));
  72         pw->protocol = protocol;
  73         pw->vrf_id = zvrf_id(zvrf);
  74         pw->client = client;
  75         pw->status = PW_STATUS_DOWN;
  76         pw->local_label = MPLS_NO_LABEL;
  77         pw->remote_label = MPLS_NO_LABEL;
  78         pw->flags = F_PSEUDOWIRE_CWORD;
  79
  80         RB_INSERT(zebra_pw_head, &zvrf->pseudowires, pw);
  81         if (pw->protocol == ZEBRA_ROUTE_STATIC) {
  82                 RB_INSERT(zebra_static_pw_head, &zvrf->static_pseudowires, pw);
  83                 QOBJ_REG(pw, zebra_pw);
  84         }
  85
  86         return pw;
  87 }
  88
  89 void zebra_pw_del(struct zebra_vrf *zvrf, struct zebra_pw *pw)
  90 {
  91         if (IS_ZEBRA_DEBUG_PW)
  92                 zlog_debug("%u: deleting pseudowire %s protocol %s", pw->vrf_id,
  93                            pw->ifname, zebra_route_string(pw->protocol));
  94
  95         /* remove nexthop tracking */
  96         zebra_deregister_rnh_pseudowire(pw->vrf_id, pw);
  97
  98         /* uninstall */
  99         if (pw->status == PW_STATUS_UP) {
 100                 hook_call(pw_uninstall, pw);
 101                 dplane_pw_uninstall(pw);
 102         } else if (pw->install_retry_timer)
 103                 THREAD_TIMER_OFF(pw->install_retry_timer);
 104
 105         /* unlink and release memory */
 106         RB_REMOVE(zebra_pw_head, &zvrf->pseudowires, pw);
 107         if (pw->protocol == ZEBRA_ROUTE_STATIC)
 108                 RB_REMOVE(zebra_static_pw_head, &zvrf->static_pseudowires, pw);
 109         XFREE(MTYPE_PW, pw);
 110 }
 111
 112 void zebra_pw_change(struct zebra_pw *pw, ifindex_t ifindex, int type, int af,
 113                      union g_addr *nexthop, uint32_t local_label,
 114                      uint32_t remote_label, uint8_t flags,
 115                      union pw_protocol_fields *data)
 116 {
 117         zebra_deregister_rnh_pseudowire(pw->vrf_id, pw);
 118
 119         pw->ifindex = ifindex;
 120         pw->type = type;
 121         pw->af = af;
 122         pw->nexthop = *nexthop;
 123         pw->local_label = local_label;
 124         pw->remote_label = remote_label;
 125         pw->flags = flags;
 126         pw->data = *data;
 127
 128         if (zebra_pw_enabled(pw))
 129                 zebra_register_rnh_pseudowire(pw->vrf_id, pw);
 130         else
 131                 zebra_pw_uninstall(pw);
 132 }
 133
 134 struct zebra_pw *zebra_pw_find(struct zebra_vrf *zvrf, const char *ifname)
 135 {
 136         struct zebra_pw pw;
 137         strlcpy(pw.ifname, ifname, sizeof(pw.ifname));
 138         return (RB_FIND(zebra_pw_head, &zvrf->pseudowires, &pw));
 139 }
 140
 141 static int zebra_pw_enabled(struct zebra_pw *pw)
 142 {
 143         if (pw->protocol == ZEBRA_ROUTE_STATIC) {
 144                 if (pw->local_label == MPLS_NO_LABEL
 145                     || pw->remote_label == MPLS_NO_LABEL || pw->af == AF_UNSPEC)
 146                         return 0;
 147                 return 1;
 148         } else
 149                 return pw->enabled;
 150 }
 151
 152 void zebra_pw_update(struct zebra_pw *pw)
 153 {
 154         if (zebra_pw_check_reachability(pw) < 0) {
 155                 zebra_pw_uninstall(pw);
 156                 /* wait for NHT and try again later */
 157         } else {
 158                 /*
 159                  * Install or reinstall the pseudowire (e.g. to update
 160                  * parameters like the nexthop or the use of the control word).
 161                  */
 162                 zebra_pw_install(pw);
 163         }
 164 }
 165
 166 static void zebra_pw_install(struct zebra_pw *pw)
 167 {
 168         if (IS_ZEBRA_DEBUG_PW)
 169                 zlog_debug("%u: installing pseudowire %s protocol %s",
 170                            pw->vrf_id, pw->ifname,
 171                            zebra_route_string(pw->protocol));
 172
 173         hook_call(pw_install, pw);
 174         if (dplane_pw_install(pw) == ZEBRA_DPLANE_REQUEST_FAILURE) {
 175                 zebra_pw_install_failure(pw);
 176                 return;
 177         }
 178
 179         if (pw->status == PW_STATUS_DOWN)
 180                 zebra_pw_update_status(pw, PW_STATUS_UP);
 181 }
 182
 183 static void zebra_pw_uninstall(struct zebra_pw *pw)
 184 {
 185         if (pw->status == PW_STATUS_DOWN)
 186                 return;
 187
 188         if (IS_ZEBRA_DEBUG_PW)
 189                 zlog_debug("%u: uninstalling pseudowire %s protocol %s",
 190                            pw->vrf_id, pw->ifname,
 191                            zebra_route_string(pw->protocol));
 192
 193         /* ignore any possible error */
 194         hook_call(pw_uninstall, pw);
 195         dplane_pw_uninstall(pw);
 196
 197         if (zebra_pw_enabled(pw))
 198                 zebra_pw_update_status(pw, PW_STATUS_DOWN);
 199 }
 200
 201 /*
 202  * Installation of the pseudowire in the kernel or hardware has failed. This
 203  * function will notify the pseudowire client about the failure and schedule
 204  * to retry the installation later. This function can be called by an external
 205  * agent that performs the pseudowire installation in an asynchronous way.
 206  */
 207 void zebra_pw_install_failure(struct zebra_pw *pw)
 208 {
 209         if (IS_ZEBRA_DEBUG_PW)
 210                 zlog_debug(
 211                         "%u: failed installing pseudowire %s, "
 212                         "scheduling retry in %u seconds",
 213                         pw->vrf_id, pw->ifname, PW_INSTALL_RETRY_INTERVAL);
 214
 215         /* schedule to retry later */
 216         THREAD_TIMER_OFF(pw->install_retry_timer);
 217         thread_add_timer(zrouter.master, zebra_pw_install_retry, pw,
 218                          PW_INSTALL_RETRY_INTERVAL, &pw->install_retry_timer);
 219
 220         zebra_pw_update_status(pw, PW_STATUS_DOWN);
 221 }
 222
 223 static int zebra_pw_install_retry(struct thread *thread)
 224 {
 225         struct zebra_pw *pw = THREAD_ARG(thread);
 226
 227         pw->install_retry_timer = NULL;
 228         zebra_pw_install(pw);
 229
 230         return 0;
 231 }
 232
 233 static void zebra_pw_update_status(struct zebra_pw *pw, int status)
 234 {
 235         pw->status = status;
 236         if (pw->client)
 237                 zsend_pw_update(pw->client, pw);
 238 }
 239
 240 static int zebra_pw_check_reachability(struct zebra_pw *pw)
 241 {
 242         struct route_entry *re;
 243         struct nexthop *nexthop;
 244
 245         /* TODO: consider GRE/L2TPv3 tunnels in addition to MPLS LSPs */
 246
 247         /* find route to the remote end of the pseudowire */
 248         re = rib_match(family2afi(pw->af), SAFI_UNICAST, pw->vrf_id,
 249                        &pw->nexthop, NULL);
 250         if (!re) {
 251                 if (IS_ZEBRA_DEBUG_PW)
 252                         zlog_debug("%s: no route found for %s", __func__,
 253                                    pw->ifname);
 254                 return -1;
 255         }
 256
 257         /*
 258          * Need to ensure that there's a label binding for all nexthops.
 259          * Otherwise, ECMP for this route could render the pseudowire unusable.
 260          */
 261         for (ALL_NEXTHOPS(re->ng, nexthop)) {
 262                 if (!nexthop->nh_label) {
 263                         if (IS_ZEBRA_DEBUG_PW)
 264                                 zlog_debug("%s: unlabeled route for %s",
 265                                            __func__, pw->ifname);
 266                         return -1;
 267                 }
 268         }
 269
 270         return 0;
 271 }
 272
 273 static int zebra_pw_client_close(struct zserv *client)
 274 {
 275         struct vrf *vrf;
 276         struct zebra_vrf *zvrf;
 277         struct zebra_pw *pw, *tmp;
 278
 279         RB_FOREACH (vrf, vrf_id_head, &vrfs_by_id) {
 280                 zvrf = vrf->info;
 281                 RB_FOREACH_SAFE (pw, zebra_pw_head, &zvrf->pseudowires, tmp) {
 282                         if (pw->client != client)
 283                                 continue;
 284                         zebra_pw_del(zvrf, pw);
 285                 }
 286         }
 287
 288         return 0;
 289 }
 290
 291 void zebra_pw_init(struct zebra_vrf *zvrf)
 292 {
 293         RB_INIT(zebra_pw_head, &zvrf->pseudowires);
 294         RB_INIT(zebra_static_pw_head, &zvrf->static_pseudowires);
 295
 296         hook_register(zserv_client_close, zebra_pw_client_close);
 297 }
 298
 299 void zebra_pw_exit(struct zebra_vrf *zvrf)
 300 {
 301         struct zebra_pw *pw;
 302
 303         while (!RB_EMPTY(zebra_pw_head, &zvrf->pseudowires)) {
 304                 pw = RB_ROOT(zebra_pw_head, &zvrf->pseudowires);
 305
 306                 zebra_pw_del(zvrf, pw);
 307         }
 308 }
 309
 310 DEFUN_NOSH (pseudowire_if,
 311             pseudowire_if_cmd,
 312             "pseudowire IFNAME",
 313             "Static pseudowire configuration\n"
 314             "Pseudowire name\n")
 315 {
 316         struct zebra_vrf *zvrf;
 317         struct zebra_pw *pw;
 318         const char *ifname;
 319         int idx = 0;
 320
 321         zvrf = vrf_info_lookup(VRF_DEFAULT);
 322         if (!zvrf)
 323                 return CMD_WARNING;
 324
 325         argv_find(argv, argc, "IFNAME", &idx);
 326         ifname = argv[idx]->arg;
 327
 328         pw = zebra_pw_find(zvrf, ifname);
 329         if (pw && pw->protocol != ZEBRA_ROUTE_STATIC) {
 330                 vty_out(vty, "%% Pseudowire is not static\n");
 331                 return CMD_WARNING;
 332         }
 333
 334         if (!pw)
 335                 pw = zebra_pw_add(zvrf, ifname, ZEBRA_ROUTE_STATIC, NULL);
 336         VTY_PUSH_CONTEXT(PW_NODE, pw);
 337
 338         return CMD_SUCCESS;
 339 }
 340
 341 DEFUN (no_pseudowire_if,
 342        no_pseudowire_if_cmd,
 343        "no pseudowire IFNAME",
 344        NO_STR
 345        "Static pseudowire configuration\n"
 346        "Pseudowire name\n")
 347 {
 348         struct zebra_vrf *zvrf;
 349         struct zebra_pw *pw;
 350         const char *ifname;
 351         int idx = 0;
 352
 353         zvrf = vrf_info_lookup(VRF_DEFAULT);
 354         if (!zvrf)
 355                 return CMD_WARNING;
 356
 357         argv_find(argv, argc, "IFNAME", &idx);
 358         ifname = argv[idx]->arg;
 359
 360         pw = zebra_pw_find(zvrf, ifname);
 361         if (pw) {
 362                 if (pw->protocol != ZEBRA_ROUTE_STATIC) {
 363                         vty_out(vty, "%% Pseudowire is not static\n");
 364                         return CMD_WARNING;
 365                 }
 366                 zebra_pw_del(zvrf, pw);
 367         }
 368
 369         return CMD_SUCCESS;
 370 }
 371
 372 DEFUN (pseudowire_labels,
 373        pseudowire_labels_cmd,
 374        "[no] mpls label local (16-1048575) remote (16-1048575)",
 375        NO_STR
 376        "MPLS L2VPN PW command\n"
 377        "MPLS L2VPN static labels\n"
 378        "Local pseudowire label\n"
 379        "Local pseudowire label\n"
 380        "Remote pseudowire label\n"
 381        "Remote pseudowire label\n")
 382 {
 383         VTY_DECLVAR_CONTEXT(zebra_pw, pw);
 384         int idx = 0;
 385         mpls_label_t local_label, remote_label;
 386
 387         if (argv_find(argv, argc, "no", &idx)) {
 388                 local_label = MPLS_NO_LABEL;
 389                 remote_label = MPLS_NO_LABEL;
 390         } else {
 391                 argv_find(argv, argc, "local", &idx);
 392                 local_label = atoi(argv[idx + 1]->arg);
 393                 argv_find(argv, argc, "remote", &idx);
 394                 remote_label = atoi(argv[idx + 1]->arg);
 395         }
 396
 397         zebra_pw_change(pw, pw->ifindex, pw->type, pw->af, &pw->nexthop,
 398                         local_label, remote_label, pw->flags, &pw->data);
 399
 400         return CMD_SUCCESS;
 401 }
 402
 403 DEFUN (pseudowire_neighbor,
 404        pseudowire_neighbor_cmd,
 405        "[no] neighbor <A.B.C.D|X:X::X:X>",
 406        NO_STR
 407        "Specify the IPv4 or IPv6 address of the remote endpoint\n"
 408        "IPv4 address\n"
 409        "IPv6 address\n")
 410 {
 411         VTY_DECLVAR_CONTEXT(zebra_pw, pw);
 412         int idx = 0;
 413         const char *address;
 414         int af;
 415         union g_addr nexthop;
 416
 417         af = AF_UNSPEC;
 418         memset(&nexthop, 0, sizeof(nexthop));
 419
 420         if (!argv_find(argv, argc, "no", &idx)) {
 421                 argv_find(argv, argc, "neighbor", &idx);
 422                 address = argv[idx + 1]->arg;
 423
 424                 if (inet_pton(AF_INET, address, &nexthop.ipv4) == 1)
 425                         af = AF_INET;
 426                 else if (inet_pton(AF_INET6, address, &nexthop.ipv6) == 1)
 427                         af = AF_INET6;
 428                 else {
 429                         vty_out(vty, "%% Malformed address\n");
 430                         return CMD_WARNING;
 431                 }
 432         }
 433
 434         zebra_pw_change(pw, pw->ifindex, pw->type, af, &nexthop,
 435                         pw->local_label, pw->remote_label, pw->flags,
 436                         &pw->data);
 437
 438         return CMD_SUCCESS;
 439 }
 440
 441 DEFUN (pseudowire_control_word,
 442        pseudowire_control_word_cmd,
 443        "[no] control-word <exclude|include>",
 444        NO_STR
 445        "Control-word options\n"
 446        "Exclude control-word in pseudowire packets\n"
 447        "Include control-word in pseudowire packets\n")
 448 {
 449         VTY_DECLVAR_CONTEXT(zebra_pw, pw);
 450         int idx = 0;
 451         uint8_t flags = 0;
 452
 453         if (argv_find(argv, argc, "no", &idx))
 454                 flags = F_PSEUDOWIRE_CWORD;
 455         else {
 456                 argv_find(argv, argc, "control-word", &idx);
 457                 if (argv[idx + 1]->text[0] == 'i')
 458                         flags = F_PSEUDOWIRE_CWORD;
 459         }
 460
 461         zebra_pw_change(pw, pw->ifindex, pw->type, pw->af, &pw->nexthop,
 462                         pw->local_label, pw->remote_label, flags, &pw->data);
 463
 464         return CMD_SUCCESS;
 465 }
 466
 467 DEFUN (show_pseudowires,
 468        show_pseudowires_cmd,
 469        "show mpls pseudowires",
 470        SHOW_STR
 471        MPLS_STR
 472        "Pseudowires\n")
 473 {
 474         struct zebra_vrf *zvrf;
 475         struct zebra_pw *pw;
 476
 477         zvrf = vrf_info_lookup(VRF_DEFAULT);
 478         if (!zvrf)
 479                 return 0;
 480
 481         vty_out(vty, "%-16s %-24s %-12s %-8s %-10s\n", "Interface", "Neighbor",
 482                 "Labels", "Protocol", "Status");
 483
 484         RB_FOREACH (pw, zebra_pw_head, &zvrf->pseudowires) {
 485                 char buf_nbr[INET6_ADDRSTRLEN];
 486                 char buf_labels[64];
 487
 488                 inet_ntop(pw->af, &pw->nexthop, buf_nbr, sizeof(buf_nbr));
 489
 490                 if (pw->local_label != MPLS_NO_LABEL
 491                     && pw->remote_label != MPLS_NO_LABEL)
 492                         snprintf(buf_labels, sizeof(buf_labels), "%u/%u",
 493                                  pw->local_label, pw->remote_label);
 494                 else
 495                         snprintf(buf_labels, sizeof(buf_labels), "-");
 496
 497                 vty_out(vty, "%-16s %-24s %-12s %-8s %-10s\n", pw->ifname,
 498                         (pw->af != AF_UNSPEC) ? buf_nbr : "-", buf_labels,
 499                         zebra_route_string(pw->protocol),
 500                         (zebra_pw_enabled(pw) && pw->status == PW_STATUS_UP)
 501                                 ? "UP"
 502                                 : "DOWN");
 503         }
 504
 505         return CMD_SUCCESS;
 506 }
 507
 508 /* Pseudowire configuration write function. */
 509 static int zebra_pw_config(struct vty *vty)
 510 {
 511         int write = 0;
 512         struct zebra_vrf *zvrf;
 513         struct zebra_pw *pw;
 514
 515         zvrf = vrf_info_lookup(VRF_DEFAULT);
 516         if (!zvrf)
 517                 return 0;
 518
 519         RB_FOREACH (pw, zebra_static_pw_head, &zvrf->static_pseudowires) {
 520                 vty_out(vty, "pseudowire %s\n", pw->ifname);
 521                 if (pw->local_label != MPLS_NO_LABEL
 522                     && pw->remote_label != MPLS_NO_LABEL)
 523                         vty_out(vty, " mpls label local %u remote %u\n",
 524                                 pw->local_label, pw->remote_label);
 525                 else
 526                         vty_out(vty,
 527                                 " ! Incomplete config, specify the static "
 528                                 "MPLS labels\n");
 529
 530                 if (pw->af != AF_UNSPEC) {
 531                         char buf[INET6_ADDRSTRLEN];
 532                         inet_ntop(pw->af, &pw->nexthop, buf, sizeof(buf));
 533                         vty_out(vty, " neighbor %s\n", buf);
 534                 } else
 535                         vty_out(vty,
 536                                 " ! Incomplete config, specify a neighbor "
 537                                 "address\n");
 538
 539                 if (!(pw->flags & F_PSEUDOWIRE_CWORD))
 540                         vty_out(vty, " control-word exclude\n");
 541
 542                 vty_out(vty, "!\n");
 543                 write = 1;
 544         }
 545
 546         return write;
 547 }
 548
 549 static struct cmd_node pw_node = {
 550         PW_NODE, "%s(config-pw)# ", 1,
 551 };
 552
 553 void zebra_pw_vty_init(void)
 554 {
 555         install_node(&pw_node, zebra_pw_config);
 556         install_default(PW_NODE);
 557
 558         install_element(CONFIG_NODE, &pseudowire_if_cmd);
 559         install_element(CONFIG_NODE, &no_pseudowire_if_cmd);
 560         install_element(PW_NODE, &pseudowire_labels_cmd);
 561         install_element(PW_NODE, &pseudowire_neighbor_cmd);
 562         install_element(PW_NODE, &pseudowire_control_word_cmd);
 563
 564         install_element(VIEW_NODE, &show_pseudowires_cmd);
 565 }