zebra/zebra_dplane.h

   1 /*
   2  * Zebra dataplane layer api interfaces.
   3  * Copyright (c) 2018 Volta Networks, Inc.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; see the file COPYING; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19
  20 #ifndef _ZEBRA_DPLANE_H
  21 #define _ZEBRA_DPLANE_H 1
  22
  23 #include "lib/zebra.h"
  24 #include "lib/prefix.h"
  25 #include "lib/nexthop.h"
  26 #include "lib/nexthop_group.h"
  27 #include "lib/queue.h"
  28 #include "zebra/zebra_ns.h"
  29 #include "zebra/rib.h"
  30 #include "zebra/zserv.h"
  31 #include "zebra/zebra_mpls.h"
  32
  33 #ifdef __cplusplus
  34 extern "C" {
  35 #endif
  36
  37 /* Key netlink info from zebra ns */
  38 struct zebra_dplane_info {
  39         ns_id_t ns_id;
  40
  41 #if defined(HAVE_NETLINK)
  42         struct nlsock nls;
  43         bool is_cmd;
  44 #endif
  45 };
  46
  47 /* Utility to fill in zns info from main zns struct */
  48 static inline void
  49 zebra_dplane_info_from_zns(struct zebra_dplane_info *zns_info,
  50                            const struct zebra_ns *zns, bool is_cmd)
  51 {
  52         zns_info->ns_id = zns->ns_id;
  53
  54 #if defined(HAVE_NETLINK)
  55         zns_info->is_cmd = is_cmd;
  56         if (is_cmd) {
  57                 zns_info->nls = zns->netlink_cmd;
  58         } else {
  59                 zns_info->nls = zns->netlink;
  60         }
  61 #endif /* NETLINK */
  62 }
  63
  64 /*
  65  * Result codes used when returning status back to the main zebra context.
  66  */
  67
  68 /*
  69  * Philosophy Note:
  70  *
  71  * Flags being SET/UNSET do not belong in the South Bound
  72  * Interface.  This Setting belongs at the calling level
  73  * because we can and will have multiple different interfaces
  74  * and we will have potentially multiple different
  75  * modules/filters to call.  As such Setting/Unsetting
  76  * success failure should be handled by the caller.
  77  */
  78 enum zebra_dplane_status {
  79         ZEBRA_DPLANE_STATUS_NONE = 0,
  80         ZEBRA_DPLANE_INSTALL_SUCCESS,
  81         ZEBRA_DPLANE_INSTALL_FAILURE,
  82         ZEBRA_DPLANE_DELETE_SUCCESS,
  83         ZEBRA_DPLANE_DELETE_FAILURE,
  84
  85 };
  86
  87 enum zebra_dplane_result {
  88         ZEBRA_DPLANE_REQUEST_QUEUED,
  89         ZEBRA_DPLANE_REQUEST_SUCCESS,
  90         ZEBRA_DPLANE_REQUEST_FAILURE,
  91 };
  92
  93 /*
  94  * API between the zebra dataplane system and the main zebra processing
  95  * context.
  96  */
  97
  98 /*
  99  * Enqueue a route install or update for the dataplane.
 100  */
 101 enum dplane_op_e {
 102         DPLANE_OP_NONE = 0,
 103
 104         /* Route update */
 105         DPLANE_OP_ROUTE_INSTALL,
 106         DPLANE_OP_ROUTE_UPDATE,
 107         DPLANE_OP_ROUTE_DELETE,
 108
 109         /* LSP update */
 110         DPLANE_OP_LSP_INSTALL,
 111         DPLANE_OP_LSP_UPDATE,
 112         DPLANE_OP_LSP_DELETE,
 113
 114         /* Pseudowire update */
 115         DPLANE_OP_PW_INSTALL,
 116         DPLANE_OP_PW_UNINSTALL,
 117
 118         /* System route notification */
 119         DPLANE_OP_SYS_ROUTE_ADD,
 120         DPLANE_OP_SYS_ROUTE_DELETE,
 121 };
 122
 123 /* Enable system route notifications */
 124 void dplane_enable_sys_route_notifs(void);
 125
 126 /*
 127  * The dataplane context struct is used to exchange info between the main zebra
 128  * context and the dataplane module(s). If these are two independent pthreads,
 129  * they cannot share existing global data structures safely.
 130  */
 131
 132 /* Define a tailq list type for context blocks. The list is exposed/public,
 133  * but the internal linkage in the context struct is private, so there
 134  * are accessor apis that support enqueue and dequeue.
 135  */
 136 TAILQ_HEAD(dplane_ctx_q, zebra_dplane_ctx);
 137
 138 /* Return a dataplane results context block after use; the caller's pointer will
 139  * be cleared.
 140  */
 141 void dplane_ctx_fini(struct zebra_dplane_ctx **pctx);
 142
 143 /* Enqueue a context block to caller's tailq. This exists so that the
 144  * context struct can remain opaque.
 145  */
 146 void dplane_ctx_enqueue_tail(struct dplane_ctx_q *q,
 147                              const struct zebra_dplane_ctx *ctx);
 148
 149 /* Append a list of context blocks to another list - again, just keeping
 150  * the context struct opaque.
 151  */
 152 void dplane_ctx_list_append(struct dplane_ctx_q *to_list,
 153                             struct dplane_ctx_q *from_list);
 154
 155 /* Dequeue a context block from the head of caller's tailq */
 156 struct zebra_dplane_ctx *dplane_ctx_dequeue(struct dplane_ctx_q *q);
 157
 158 /*
 159  * Accessors for information from the context object
 160  */
 161 enum zebra_dplane_result dplane_ctx_get_status(
 162         const struct zebra_dplane_ctx *ctx);
 163 void dplane_ctx_set_status(struct zebra_dplane_ctx *ctx,
 164                            enum zebra_dplane_result status);
 165 const char *dplane_res2str(enum zebra_dplane_result res);
 166
 167 enum dplane_op_e dplane_ctx_get_op(const struct zebra_dplane_ctx *ctx);
 168 const char *dplane_op2str(enum dplane_op_e op);
 169
 170 const struct prefix *dplane_ctx_get_dest(const struct zebra_dplane_ctx *ctx);
 171
 172 /* Retrieve last/current provider id */
 173 uint32_t dplane_ctx_get_provider(const struct zebra_dplane_ctx *ctx);
 174
 175 /* Providers running before the kernel can control whether a kernel
 176  * update should be done.
 177  */
 178 void dplane_ctx_set_skip_kernel(struct zebra_dplane_ctx *ctx);
 179 bool dplane_ctx_is_skip_kernel(const struct zebra_dplane_ctx *ctx);
 180
 181 /* Source prefix is a little special - use convention to return NULL
 182  * to mean "no src prefix"
 183  */
 184 const struct prefix *dplane_ctx_get_src(const struct zebra_dplane_ctx *ctx);
 185
 186 bool dplane_ctx_is_update(const struct zebra_dplane_ctx *ctx);
 187 uint32_t dplane_ctx_get_seq(const struct zebra_dplane_ctx *ctx);
 188 uint32_t dplane_ctx_get_old_seq(const struct zebra_dplane_ctx *ctx);
 189 vrf_id_t dplane_ctx_get_vrf(const struct zebra_dplane_ctx *ctx);
 190
 191 /* Accessors for route update information */
 192 int dplane_ctx_get_type(const struct zebra_dplane_ctx *ctx);
 193 int dplane_ctx_get_old_type(const struct zebra_dplane_ctx *ctx);
 194 afi_t dplane_ctx_get_afi(const struct zebra_dplane_ctx *ctx);
 195 safi_t dplane_ctx_get_safi(const struct zebra_dplane_ctx *ctx);
 196 uint32_t dplane_ctx_get_table(const struct zebra_dplane_ctx *ctx);
 197 route_tag_t dplane_ctx_get_tag(const struct zebra_dplane_ctx *ctx);
 198 route_tag_t dplane_ctx_get_old_tag(const struct zebra_dplane_ctx *ctx);
 199 uint16_t dplane_ctx_get_instance(const struct zebra_dplane_ctx *ctx);
 200 uint16_t dplane_ctx_get_old_instance(const struct zebra_dplane_ctx *ctx);
 201 uint32_t dplane_ctx_get_metric(const struct zebra_dplane_ctx *ctx);
 202 uint32_t dplane_ctx_get_old_metric(const struct zebra_dplane_ctx *ctx);
 203 uint32_t dplane_ctx_get_mtu(const struct zebra_dplane_ctx *ctx);
 204 uint32_t dplane_ctx_get_nh_mtu(const struct zebra_dplane_ctx *ctx);
 205 uint8_t dplane_ctx_get_distance(const struct zebra_dplane_ctx *ctx);
 206 uint8_t dplane_ctx_get_old_distance(const struct zebra_dplane_ctx *ctx);
 207
 208 const struct nexthop_group *dplane_ctx_get_ng(
 209         const struct zebra_dplane_ctx *ctx);
 210 const struct nexthop_group *dplane_ctx_get_old_ng(
 211         const struct zebra_dplane_ctx *ctx);
 212
 213 /* Accessors for LSP information */
 214 mpls_label_t dplane_ctx_get_in_label(const struct zebra_dplane_ctx *ctx);
 215 uint8_t dplane_ctx_get_addr_family(const struct zebra_dplane_ctx *ctx);
 216 uint32_t dplane_ctx_get_lsp_flags(const struct zebra_dplane_ctx *ctx);
 217 const zebra_nhlfe_t *dplane_ctx_get_nhlfe(const struct zebra_dplane_ctx *ctx);
 218 const zebra_nhlfe_t *dplane_ctx_get_best_nhlfe(
 219         const struct zebra_dplane_ctx *ctx);
 220 uint32_t dplane_ctx_get_lsp_num_ecmp(const struct zebra_dplane_ctx *ctx);
 221
 222 /* Accessors for pseudowire information */
 223 const char *dplane_ctx_get_pw_ifname(const struct zebra_dplane_ctx *ctx);
 224 mpls_label_t dplane_ctx_get_pw_local_label(const struct zebra_dplane_ctx *ctx);
 225 mpls_label_t dplane_ctx_get_pw_remote_label(const struct zebra_dplane_ctx *ctx);
 226 int dplane_ctx_get_pw_type(const struct zebra_dplane_ctx *ctx);
 227 int dplane_ctx_get_pw_af(const struct zebra_dplane_ctx *ctx);
 228 uint32_t dplane_ctx_get_pw_flags(const struct zebra_dplane_ctx *ctx);
 229 int dplane_ctx_get_pw_status(const struct zebra_dplane_ctx *ctx);
 230 const union g_addr *dplane_ctx_get_pw_dest(
 231         const struct zebra_dplane_ctx *ctx);
 232 const union pw_protocol_fields *dplane_ctx_get_pw_proto(
 233         const struct zebra_dplane_ctx *ctx);
 234 const struct nexthop_group *dplane_ctx_get_pw_nhg(
 235         const struct zebra_dplane_ctx *ctx);
 236
 237 /* Namespace info - esp. for netlink communication */
 238 const struct zebra_dplane_info *dplane_ctx_get_ns(
 239         const struct zebra_dplane_ctx *ctx);
 240
 241 /* Indicates zebra shutdown/exit is in progress. Some operations may be
 242  * simplified or skipped during shutdown processing.
 243  */
 244 bool dplane_is_in_shutdown(void);
 245
 246 /*
 247  * Enqueue route change operations for the dataplane.
 248  */
 249 enum zebra_dplane_result dplane_route_add(struct route_node *rn,
 250                                           struct route_entry *re);
 251
 252 enum zebra_dplane_result dplane_route_update(struct route_node *rn,
 253                                              struct route_entry *re,
 254                                              struct route_entry *old_re);
 255
 256 enum zebra_dplane_result dplane_route_delete(struct route_node *rn,
 257                                              struct route_entry *re);
 258
 259 /* Notify the dplane when system/connected routes change */
 260 enum zebra_dplane_result dplane_sys_route_add(struct route_node *rn,
 261                                               struct route_entry *re);
 262 enum zebra_dplane_result dplane_sys_route_del(struct route_node *rn,
 263                                               struct route_entry *re);
 264
 265 /*
 266  * Enqueue LSP change operations for the dataplane.
 267  */
 268 enum zebra_dplane_result dplane_lsp_add(zebra_lsp_t *lsp);
 269 enum zebra_dplane_result dplane_lsp_update(zebra_lsp_t *lsp);
 270 enum zebra_dplane_result dplane_lsp_delete(zebra_lsp_t *lsp);
 271
 272 /*
 273  * Enqueue pseudowire operations for the dataplane.
 274  */
 275 enum zebra_dplane_result dplane_pw_install(struct zebra_pw *pw);
 276 enum zebra_dplane_result dplane_pw_uninstall(struct zebra_pw *pw);
 277
 278 /* Retrieve the limit on the number of pending, unprocessed updates. */
 279 uint32_t dplane_get_in_queue_limit(void);
 280
 281 /* Configure limit on the number of pending, queued updates. If 'unset', reset
 282  * to default value.
 283  */
 284 void dplane_set_in_queue_limit(uint32_t limit, bool set);
 285
 286 /* Retrieve the current queue depth of incoming, unprocessed updates */
 287 uint32_t dplane_get_in_queue_len(void);
 288
 289 /*
 290  * Vty/cli apis
 291  */
 292 int dplane_show_helper(struct vty *vty, bool detailed);
 293 int dplane_show_provs_helper(struct vty *vty, bool detailed);
 294
 295
 296 /*
 297  * Dataplane providers: modules that process or consume dataplane events.
 298  */
 299
 300 struct zebra_dplane_provider;
 301
 302 /* Support string name for a dataplane provider */
 303 #define DPLANE_PROVIDER_NAMELEN 64
 304
 305 /* Priority or ordering values for providers. The idea is that there may be
 306  * some pre-processing, followed by an external or remote dataplane,
 307  * followed by the kernel, followed by some post-processing step (such as
 308  * the fpm output stream.)
 309  */
 310 enum dplane_provider_prio {
 311         DPLANE_PRIO_NONE = 0,
 312         DPLANE_PRIO_PREPROCESS,
 313         DPLANE_PRIO_PRE_KERNEL,
 314         DPLANE_PRIO_KERNEL,
 315         DPLANE_PRIO_POSTPROCESS,
 316         DPLANE_PRIO_LAST
 317 };
 318
 319 /* Flags values used during provider registration. */
 320 #define DPLANE_PROV_FLAGS_DEFAULT  0x0
 321
 322 /* Provider will be spawning its own worker thread */
 323 #define DPLANE_PROV_FLAG_THREADED  0x1
 324
 325
 326 /* Provider registration: ordering or priority value, callbacks, and optional
 327  * opaque data value. If 'prov_p', return the newly-allocated provider object
 328  * on success.
 329  */
 330
 331 /* Providers offer an entry-point for incoming work, called in the context of
 332  * the dataplane pthread. The dataplane pthread enqueues any new work to the
 333  * provider's 'inbound' queue, then calls the callback. The dataplane
 334  * then checks the provider's outbound queue for completed work.
 335  */
 336
 337 /* Providers offer an entry-point for shutdown and cleanup. This is called
 338  * with 'early' during shutdown, to indicate that the dataplane subsystem
 339  * is allowing work to move through the providers and finish.
 340  * When called without 'early', the provider should release
 341  * all resources (if it has any allocated).
 342  */
 343 int dplane_provider_register(const char *name,
 344                              enum dplane_provider_prio prio,
 345                              int flags,
 346                              int (*fp)(struct zebra_dplane_provider *),
 347                              int (*fini_fp)(struct zebra_dplane_provider *,
 348                                             bool early),
 349                              void *data,
 350                              struct zebra_dplane_provider **prov_p);
 351
 352 /* Accessors for provider attributes */
 353 const char *dplane_provider_get_name(const struct zebra_dplane_provider *prov);
 354 uint32_t dplane_provider_get_id(const struct zebra_dplane_provider *prov);
 355 void *dplane_provider_get_data(const struct zebra_dplane_provider *prov);
 356 bool dplane_provider_is_threaded(const struct zebra_dplane_provider *prov);
 357
 358 /* Lock/unlock a provider's mutex - iff the provider was registered with
 359  * the THREADED flag.
 360  */
 361 void dplane_provider_lock(struct zebra_dplane_provider *prov);
 362 void dplane_provider_unlock(struct zebra_dplane_provider *prov);
 363
 364 /* Obtain thread_master for dataplane thread */
 365 struct thread_master *dplane_get_thread_master(void);
 366
 367 /* Providers should (generally) limit number of updates per work cycle */
 368 int dplane_provider_get_work_limit(const struct zebra_dplane_provider *prov);
 369
 370 /* Provider api to signal that work/events are available
 371  * for the dataplane pthread.
 372  */
 373 int dplane_provider_work_ready(void);
 374
 375 /* Dequeue, maintain associated counter and locking */
 376 struct zebra_dplane_ctx *dplane_provider_dequeue_in_ctx(
 377         struct zebra_dplane_provider *prov);
 378
 379 /* Dequeue work to a list, maintain counter and locking, return count */
 380 int dplane_provider_dequeue_in_list(struct zebra_dplane_provider *prov,
 381                                     struct dplane_ctx_q *listp);
 382
 383 /* Enqueue, maintain associated counter and locking */
 384 void dplane_provider_enqueue_out_ctx(struct zebra_dplane_provider *prov,
 385                                      struct zebra_dplane_ctx *ctx);
 386
 387 /*
 388  * Initialize the dataplane modules at zebra startup. This is currently called
 389  * by the rib module. Zebra registers a results callback with the dataplane.
 390  * The callback is called in the dataplane pthread context,
 391  * so the expectation is that the contexts are queued for the zebra
 392  * main pthread.
 393  */
 394 void zebra_dplane_init(int (*) (struct dplane_ctx_q *));
 395
 396 /*
 397  * Start the dataplane pthread. This step needs to be run later than the
 398  * 'init' step, in case zebra has fork-ed.
 399  */
 400 void zebra_dplane_start(void);
 401
 402 /* Finalize/cleanup apis, one called early as shutdown is starting,
 403  * one called late at the end of zebra shutdown, and then one called
 404  * from the zebra main pthread to stop the dplane pthread and
 405  * free all resources.
 406  *
 407  * Zebra expects to try to clean up all vrfs and all routes during
 408  * shutdown, so the dplane must be available until very late.
 409  */
 410 void zebra_dplane_pre_finish(void);
 411 void zebra_dplane_finish(void);
 412 void zebra_dplane_shutdown(void);
 413
 414 #ifdef __cplusplus
 415 }
 416 #endif
 417
 418 #endif  /* _ZEBRA_DPLANE_H */