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