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/openbsd-queue.h"
  28 #include "zebra/zebra_ns.h"
  29 #include "zebra/rib.h"
  30 #include "zebra/zserv.h"
  31
  32
  33 /* Key netlink info from zebra ns */
  34 struct zebra_dplane_info {
  35         ns_id_t ns_id;
  36
  37 #if defined(HAVE_NETLINK)
  38         struct nlsock nls;
  39         bool is_cmd;
  40 #endif
  41 };
  42
  43 /* Utility to fill in zns info from main zns struct */
  44 static inline void
  45 zebra_dplane_info_from_zns(struct zebra_dplane_info *zns_info,
  46                            const struct zebra_ns *zns, bool is_cmd)
  47 {
  48         zns_info->ns_id = zns->ns_id;
  49
  50 #if defined(HAVE_NETLINK)
  51         zns_info->is_cmd = is_cmd;
  52         if (is_cmd) {
  53                 zns_info->nls = zns->netlink_cmd;
  54         } else {
  55                 zns_info->nls = zns->netlink;
  56         }
  57 #endif /* NETLINK */
  58 }
  59
  60 /*
  61  * Result codes used when returning status back to the main zebra context.
  62  */
  63
  64 /*
  65  * Philosophy Note:
  66  *
  67  * Flags being SET/UNSET do not belong in the South Bound
  68  * Interface.  This Setting belongs at the calling level
  69  * because we can and will have multiple different interfaces
  70  * and we will have potentially multiple different
  71  * modules/filters to call.  As such Setting/Unsetting
  72  * success failure should be handled by the caller.
  73  */
  74 enum zebra_dplane_status {
  75         ZEBRA_DPLANE_STATUS_NONE = 0,
  76         ZEBRA_DPLANE_INSTALL_SUCCESS,
  77         ZEBRA_DPLANE_INSTALL_FAILURE,
  78         ZEBRA_DPLANE_DELETE_SUCCESS,
  79         ZEBRA_DPLANE_DELETE_FAILURE,
  80
  81 };
  82
  83 enum zebra_dplane_result {
  84         ZEBRA_DPLANE_REQUEST_QUEUED,
  85         ZEBRA_DPLANE_REQUEST_SUCCESS,
  86         ZEBRA_DPLANE_REQUEST_FAILURE,
  87 };
  88
  89 /*
  90  * API between the zebra dataplane system and the main zebra processing
  91  * context.
  92  */
  93
  94 /*
  95  * Enqueue a route install or update for the dataplane.
  96  */
  97 enum dplane_op_e {
  98         DPLANE_OP_NONE = 0,
  99
 100         /* Route update */
 101         DPLANE_OP_ROUTE_INSTALL,
 102         DPLANE_OP_ROUTE_UPDATE,
 103         DPLANE_OP_ROUTE_DELETE,
 104
 105 };
 106
 107 /*
 108  * The dataplane context struct is used to exchange info between the main zebra
 109  * context and the dataplane module(s). If these are two independent pthreads,
 110  * they cannot share existing global data structures safely.
 111  */
 112
 113 /* Define a tailq list type for context blocks. The list is exposed/public,
 114  * but the internal linkage in the context struct is private, so there
 115  * are accessor apis that support enqueue and dequeue.
 116  */
 117 TAILQ_HEAD(dplane_ctx_q, zebra_dplane_ctx);
 118
 119 /* Return a dataplane results context block after use; the caller's pointer will
 120  * be cleared.
 121  */
 122 void dplane_ctx_fini(struct zebra_dplane_ctx **pctx);
 123
 124 /* Enqueue a context block to caller's tailq. This just exists so that the
 125  * context struct can remain opaque.
 126  */
 127 void dplane_ctx_enqueue_tail(struct dplane_ctx_q *q,
 128                              const struct zebra_dplane_ctx *ctx);
 129
 130 /* Dequeue a context block from the head of caller's tailq */
 131 void dplane_ctx_dequeue(struct dplane_ctx_q *q, struct zebra_dplane_ctx **ctxp);
 132
 133 /*
 134  * Accessors for information from the context object
 135  */
 136 enum zebra_dplane_result dplane_ctx_get_status(
 137         const struct zebra_dplane_ctx *ctx);
 138 const char *dplane_res2str(enum zebra_dplane_result res);
 139
 140 enum dplane_op_e dplane_ctx_get_op(const struct zebra_dplane_ctx *ctx);
 141 const char *dplane_op2str(enum dplane_op_e op);
 142
 143 const struct prefix *dplane_ctx_get_dest(const struct zebra_dplane_ctx *ctx);
 144
 145 /* Source prefix is a little special - use convention to return NULL
 146  * to mean "no src prefix"
 147  */
 148 const struct prefix *dplane_ctx_get_src(const struct zebra_dplane_ctx *ctx);
 149
 150 bool dplane_ctx_is_update(const struct zebra_dplane_ctx *ctx);
 151 uint32_t dplane_ctx_get_seq(const struct zebra_dplane_ctx *ctx);
 152 uint32_t dplane_ctx_get_old_seq(const struct zebra_dplane_ctx *ctx);
 153 vrf_id_t dplane_ctx_get_vrf(const struct zebra_dplane_ctx *ctx);
 154 int dplane_ctx_get_type(const struct zebra_dplane_ctx *ctx);
 155 int dplane_ctx_get_old_type(const struct zebra_dplane_ctx *ctx);
 156 afi_t dplane_ctx_get_afi(const struct zebra_dplane_ctx *ctx);
 157 safi_t dplane_ctx_get_safi(const struct zebra_dplane_ctx *ctx);
 158 uint32_t dplane_ctx_get_table(const struct zebra_dplane_ctx *ctx);
 159 route_tag_t dplane_ctx_get_tag(const struct zebra_dplane_ctx *ctx);
 160 route_tag_t dplane_ctx_get_old_tag(const struct zebra_dplane_ctx *ctx);
 161 uint16_t dplane_ctx_get_instance(const struct zebra_dplane_ctx *ctx);
 162 uint16_t dplane_ctx_get_old_instance(const struct zebra_dplane_ctx *ctx);
 163 uint32_t dplane_ctx_get_metric(const struct zebra_dplane_ctx *ctx);
 164 uint32_t dplane_ctx_get_old_metric(const struct zebra_dplane_ctx *ctx);
 165 uint32_t dplane_ctx_get_mtu(const struct zebra_dplane_ctx *ctx);
 166 uint32_t dplane_ctx_get_nh_mtu(const struct zebra_dplane_ctx *ctx);
 167 uint8_t dplane_ctx_get_distance(const struct zebra_dplane_ctx *ctx);
 168 uint8_t dplane_ctx_get_old_distance(const struct zebra_dplane_ctx *ctx);
 169
 170 const struct nexthop_group *dplane_ctx_get_ng(
 171         const struct zebra_dplane_ctx *ctx);
 172 const struct nexthop_group *dplane_ctx_get_old_ng(
 173         const struct zebra_dplane_ctx *ctx);
 174
 175 const struct zebra_dplane_info *dplane_ctx_get_ns(
 176         const struct zebra_dplane_ctx *ctx);
 177
 178 /* Indicates zebra shutdown/exit is in progress. Some operations may be
 179  * simplified or skipped during shutdown processing.
 180  */
 181 bool dplane_is_in_shutdown(void);
 182
 183 /*
 184  * Enqueue route change operations for the dataplane.
 185  */
 186 enum zebra_dplane_result dplane_route_add(struct route_node *rn,
 187                                           struct route_entry *re);
 188
 189 enum zebra_dplane_result dplane_route_update(struct route_node *rn,
 190                                              struct route_entry *re,
 191                                              struct route_entry *old_re);
 192
 193 enum zebra_dplane_result dplane_route_delete(struct route_node *rn,
 194                                              struct route_entry *re);
 195
 196 /* Retrieve the limit on the number of pending, unprocessed updates. */
 197 uint32_t dplane_get_in_queue_limit(void);
 198
 199 /* Configure limit on the number of pending, queued updates. If 'unset', reset
 200  * to default value.
 201  */
 202 void dplane_set_in_queue_limit(uint32_t limit, bool set);
 203
 204 /* Retrieve the current queue depth of incoming, unprocessed updates */
 205 uint32_t dplane_get_in_queue_len(void);
 206
 207 /*
 208  * Vty/cli apis
 209  */
 210 int dplane_show_helper(struct vty *vty, bool detailed);
 211 int dplane_show_provs_helper(struct vty *vty, bool detailed);
 212
 213
 214 /*
 215  * Dataplane providers: modules that consume dataplane events.
 216  */
 217
 218 /* Support string name for a dataplane provider */
 219 #define DPLANE_PROVIDER_NAMELEN 64
 220
 221 /* Priority or ordering values for providers. The idea is that there may be
 222  * some pre-processing, followed by an external or remote dataplane,
 223  * followed by the kernel, followed by some post-processing step (such as
 224  * the fpm output stream.)
 225  */
 226 enum dplane_provider_prio_e {
 227         DPLANE_PRIO_NONE = 0,
 228         DPLANE_PRIO_PREPROCESS,
 229         DPLANE_PRIO_PRE_KERNEL,
 230         DPLANE_PRIO_KERNEL,
 231         DPLANE_PRIO_POSTPROCESS,
 232         DPLANE_PRIO_LAST
 233 };
 234
 235 /* Provider's entry-point to process a context block */
 236 typedef int (*dplane_provider_process_fp)(struct zebra_dplane_ctx *ctx);
 237
 238 /* Provider's entry-point for shutdown and cleanup */
 239 typedef int (*dplane_provider_fini_fp)(void);
 240
 241 /* Provider registration */
 242 int dplane_provider_register(const char *name,
 243                              enum dplane_provider_prio_e prio,
 244                              dplane_provider_process_fp fp,
 245                              dplane_provider_fini_fp fini_fp);
 246
 247 /*
 248  * Results are returned to zebra core via a callback
 249  */
 250 typedef int (*dplane_results_fp)(const struct zebra_dplane_ctx *ctx);
 251
 252 /*
 253  * Zebra registers a results callback with the dataplane. The callback is
 254  * called in the dataplane thread context, so the expectation is that the
 255  * context is queued (or that processing is very limited).
 256  */
 257 int dplane_results_register(dplane_results_fp fp);
 258
 259 /*
 260  * Initialize the dataplane modules at zebra startup. This is currently called
 261  * by the rib module.
 262  */
 263 void zebra_dplane_init(void);
 264
 265 /* Finalize/cleanup apis, one called early as shutdown is starting,
 266  * one called late at the end of zebra shutdown, and then one called
 267  * from the zebra main thread to stop the dplane thread free all resources.
 268  *
 269  * Zebra expects to try to clean up all vrfs and all routes during
 270  * shutdown, so the dplane must be available until very late.
 271  */
 272 void zebra_dplane_pre_finish(void);
 273 void zebra_dplane_finish(void);
 274 void zebra_dplane_shutdown(void);
 275
 276 #endif  /* _ZEBRA_DPLANE_H */