Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 390 insertions, 0 deletions

diff --git a/zebra/zebra_nhg.h b/zebra/zebra_nhg.h
new file mode 100644
index 0000000..6179be3
--- /dev/null
+++ b/zebra/zebra_nhg.h
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Zebra Nexthop Group header.
+ * Copyright (C) 2019 Cumulus Networks, Inc.
+ *                    Donald Sharp
+ *                    Stephen Worley
+ */
+#ifndef __ZEBRA_NHG_H__
+#define __ZEBRA_NHG_H__
+
+#include "lib/nexthop.h"
+#include "lib/nexthop_group.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This struct is used exclusively for dataplane
+ * interaction via a dataplane context.
+ *
+ * It is designed to mimic the netlink nexthop_grp
+ * struct in include/linux/nexthop.h
+ */
+struct nh_grp {
+	uint32_t id;
+	uint8_t weight;
+};
+
+PREDECL_RBTREE_UNIQ(nhg_connected_tree);
+
+/*
+ * Hashtables containing nhg entries is in `zebra_router`.
+ */
+struct nhg_hash_entry {
+	uint32_t id;
+	afi_t afi;
+	vrf_id_t vrf_id;
+
+	/* Time since last update */
+	time_t uptime;
+
+	/* Source protocol - zebra or another daemon */
+	int type;
+
+	/* zapi instance and session id, for groups from other daemons */
+	uint16_t zapi_instance;
+	uint32_t zapi_session;
+
+	struct nexthop_group nhg;
+
+	/* If supported, a mapping of backup nexthops. */
+	struct nhg_backup_info *backup_info;
+
+	/* If this is not a group, it
+	 * will be a single nexthop
+	 * and must have an interface
+	 * associated with it.
+	 * Otherwise, this will be null.
+	 */
+	struct interface *ifp;
+
+	uint32_t refcnt;
+	uint32_t dplane_ref;
+
+	uint32_t flags;
+
+	/* Dependency trees for other entries.
+	 * For instance a group with two
+	 * nexthops will have two dependencies
+	 * pointing to those nhg_hash_entries.
+	 *
+	 * Using a rb tree here to make lookups
+	 * faster with ID's.
+	 *
+	 * nhg_depends the RB tree of entries that this
+	 * group contains.
+	 *
+	 * nhg_dependents the RB tree of entries that
+	 * this group is being used by
+	 *
+	 * NHG id 3 with nexthops id 1/2
+	 * nhg(3)->nhg_depends has 1 and 2 in the tree
+	 * nhg(3)->nhg_dependents is empty
+	 *
+	 * nhg(1)->nhg_depends is empty
+	 * nhg(1)->nhg_dependents is 3 in the tree
+	 *
+	 * nhg(2)->nhg_depends is empty
+	 * nhg(3)->nhg_dependents is 3 in the tree
+	 */
+	struct nhg_connected_tree_head nhg_depends, nhg_dependents;
+
+	struct event *timer;
+
+/*
+ * Is this nexthop group valid, ie all nexthops are fully resolved.
+ * What is fully resolved?  It's a nexthop that is either self contained
+ * and correct( ie no recursive pointer ) or a nexthop that is recursively
+ * resolved and correct.
+ */
+#define NEXTHOP_GROUP_VALID (1 << 0)
+/*
+ * Has this nexthop group been installed?  At this point in time, this
+ * means that the data-plane has been told about this nexthop group
+ * and it's possible usage by a route entry.
+ */
+#define NEXTHOP_GROUP_INSTALLED (1 << 1)
+/*
+ * Has the nexthop group been queued to be send to the FIB?
+ * The NEXTHOP_GROUP_VALID flag should also be set by this point.
+ */
+#define NEXTHOP_GROUP_QUEUED (1 << 2)
+/*
+ * Is this a nexthop that is recursively resolved?
+ */
+#define NEXTHOP_GROUP_RECURSIVE (1 << 3)
+
+/*
+ * Backup nexthop support - identify groups that are backups for
+ * another group.
+ */
+#define NEXTHOP_GROUP_BACKUP (1 << 4)
+
+/*
+ * The NHG has been release by an upper level protocol via the
+ * `zebra_nhg_proto_del()` API.
+ *
+ * We use this flag to track this state in case the NHG is still being used
+ * by routes therefore holding their refcnts as well. Otherwise, the NHG will
+ * be removed and uninstalled.
+ *
+ */
+#define NEXTHOP_GROUP_PROTO_RELEASED (1 << 5)
+
+/*
+ * When deleting a NHG notice that it is still installed
+ * and if it is, slightly delay the actual removal to
+ * the future.  So that upper level protocols might
+ * be able to take advantage of some NHG's that
+ * are there
+ */
+#define NEXTHOP_GROUP_KEEP_AROUND (1 << 6)
+
+/*
+ * Track FPM installation status..
+ */
+#define NEXTHOP_GROUP_FPM (1 << 6)
+};
+
+/* Upper 4 bits of the NHG are reserved for indicating the NHG type */
+#define NHG_ID_TYPE_POS 28
+enum nhg_type {
+	NHG_TYPE_L3 = 0,
+	NHG_TYPE_L2_NH, /* NHs in a L2 NHG used as a MAC/FDB dest */
+	NHG_TYPE_L2,    /* L2 NHG used as a MAC/FDB dest */
+};
+
+/* Was this one we created, either this session or previously? */
+#define ZEBRA_NHG_CREATED(NHE)                                                 \
+	(((NHE->type) <= ZEBRA_ROUTE_MAX) && (NHE->type != ZEBRA_ROUTE_KERNEL))
+
+/* Is this an NHE owned by zebra and not an upper level protocol? */
+#define ZEBRA_OWNED(NHE) (NHE->type == ZEBRA_ROUTE_NHG)
+
+#define PROTO_OWNED(NHE) (NHE->id >= ZEBRA_NHG_PROTO_LOWER)
+
+/*
+ * Backup nexthops: this is a group object itself, so
+ * that the backup nexthops can use the same code as a normal object.
+ */
+struct nhg_backup_info {
+	struct nhg_hash_entry *nhe;
+};
+
+enum nhg_ctx_op_e {
+	NHG_CTX_OP_NONE = 0,
+	NHG_CTX_OP_NEW,
+	NHG_CTX_OP_DEL,
+};
+
+enum nhg_ctx_status {
+	NHG_CTX_NONE = 0,
+	NHG_CTX_QUEUED,
+	NHG_CTX_REQUEUED,
+	NHG_CTX_SUCCESS,
+	NHG_CTX_FAILURE,
+};
+
+/*
+ * Context needed to queue nhg updates on the
+ * work queue.
+ */
+struct nhg_ctx {
+
+	/* Unique ID */
+	uint32_t id;
+
+	vrf_id_t vrf_id;
+	afi_t afi;
+
+	/*
+	 * This should only ever be ZEBRA_ROUTE_NHG unless we get a a kernel
+	 * created nexthop not made by us.
+	 */
+	int type;
+
+	/* If its a group array, how many? */
+	uint8_t count;
+
+	/* Its either a single nexthop or an array of ID's */
+	union {
+		struct nexthop nh;
+		struct nh_grp grp[MULTIPATH_NUM];
+	} u;
+
+	struct nhg_resilience resilience;
+	enum nhg_ctx_op_e op;
+	enum nhg_ctx_status status;
+};
+
+/* Global control to disable use of kernel nexthops, if available. We can't
+ * force the kernel to support nexthop ids, of course, but we can disable
+ * zebra's use of them, for testing e.g. By default, if the kernel supports
+ * nexthop ids, zebra uses them.
+ */
+void zebra_nhg_enable_kernel_nexthops(bool set);
+bool zebra_nhg_kernel_nexthops_enabled(void);
+
+/* Global control for zebra to only use proto-owned nexthops */
+void zebra_nhg_set_proto_nexthops_only(bool set);
+bool zebra_nhg_proto_nexthops_only(void);
+
+/* Global control for use of activated backups for recursive resolution. */
+void zebra_nhg_set_recursive_use_backups(bool set);
+bool zebra_nhg_recursive_use_backups(void);
+
+/**
+ * NHE abstracted tree functions.
+ * Use these where possible instead of direct access.
+ */
+struct nhg_hash_entry *zebra_nhg_alloc(void);
+void zebra_nhg_free(struct nhg_hash_entry *nhe);
+/* In order to clear a generic hash, we need a generic api, sigh. */
+void zebra_nhg_hash_free(void *p);
+void zebra_nhg_hash_free_zero_id(struct hash_bucket *b, void *arg);
+
+/* Init an nhe, for use in a hash lookup for example. There's some fuzziness
+ * if the nhe represents only a single nexthop, so we try to capture that
+ * variant also.
+ */
+void zebra_nhe_init(struct nhg_hash_entry *nhe, afi_t afi,
+		    const struct nexthop *nh);
+
+/*
+ * Shallow copy of 'orig', into new/allocated nhe.
+ */
+struct nhg_hash_entry *zebra_nhe_copy(const struct nhg_hash_entry *orig,
+				      uint32_t id);
+
+/* Allocate, free backup nexthop info objects */
+struct nhg_backup_info *zebra_nhg_backup_alloc(void);
+void zebra_nhg_backup_free(struct nhg_backup_info **p);
+
+struct nexthop_group *zebra_nhg_get_backup_nhg(struct nhg_hash_entry *nhe);
+
+extern struct nhg_hash_entry *zebra_nhg_resolve(struct nhg_hash_entry *nhe);
+
+extern unsigned int zebra_nhg_depends_count(const struct nhg_hash_entry *nhe);
+extern bool zebra_nhg_depends_is_empty(const struct nhg_hash_entry *nhe);
+
+extern unsigned int
+zebra_nhg_dependents_count(const struct nhg_hash_entry *nhe);
+extern bool zebra_nhg_dependents_is_empty(const struct nhg_hash_entry *nhe);
+
+/* Lookup ID, doesn't create */
+extern struct nhg_hash_entry *zebra_nhg_lookup_id(uint32_t id);
+
+/* Hash functions */
+extern uint32_t zebra_nhg_hash_key(const void *arg);
+extern uint32_t zebra_nhg_id_key(const void *arg);
+
+extern bool zebra_nhg_hash_equal(const void *arg1, const void *arg2);
+extern bool zebra_nhg_hash_id_equal(const void *arg1, const void *arg2);
+
+/*
+ * Process a context off of a queue.
+ * Specifically this should be from
+ * the rib meta queue.
+ */
+extern int nhg_ctx_process(struct nhg_ctx *ctx);
+void nhg_ctx_free(struct nhg_ctx **ctx);
+
+/* Find via kernel nh creation */
+extern int zebra_nhg_kernel_find(uint32_t id, struct nexthop *nh,
+				 struct nh_grp *grp, uint8_t count,
+				 vrf_id_t vrf_id, afi_t afi, int type,
+				 int startup,
+				 struct nhg_resilience *resilience);
+/* Del via kernel */
+extern int zebra_nhg_kernel_del(uint32_t id, vrf_id_t vrf_id);
+
+/* Find an nhe based on a nexthop_group */
+extern struct nhg_hash_entry *zebra_nhg_rib_find(uint32_t id,
+						 struct nexthop_group *nhg,
+						 afi_t rt_afi, int type);
+
+/* Find an nhe based on a route's nhe, used during route creation */
+struct nhg_hash_entry *
+zebra_nhg_rib_find_nhe(struct nhg_hash_entry *rt_nhe, afi_t rt_afi);
+
+
+/**
+ * Functions for Add/Del/Replace via protocol NHG creation.
+ *
+ * The NHEs will not be hashed. They will only be present in the
+ * ID table and therefore not sharable.
+ *
+ * It is the owning protocols job to manage these.
+ */
+
+/*
+ * Add NHE. If already exists, Replace.
+ *
+ * Returns allocated NHE on success, otherwise NULL.
+ */
+struct nhg_hash_entry *zebra_nhg_proto_add(uint32_t id, int type,
+					   uint16_t instance, uint32_t session,
+					   struct nexthop_group *nhg,
+					   afi_t afi);
+
+/*
+ * Del NHE.
+ *
+ * Returns deleted NHE on success, otherwise NULL.
+ *
+ * Caller must decrement ref with zebra_nhg_decrement_ref() when done.
+ */
+struct nhg_hash_entry *zebra_nhg_proto_del(uint32_t id, int type);
+
+/*
+ * Remove specific by proto NHGs.
+ *
+ * Called after client disconnect.
+ *
+ */
+unsigned long zebra_nhg_score_proto(int type);
+
+/* Reference counter functions */
+extern void zebra_nhg_decrement_ref(struct nhg_hash_entry *nhe);
+extern void zebra_nhg_increment_ref(struct nhg_hash_entry *nhe);
+
+/* Check validity of nhe, if invalid will update dependents as well */
+extern void zebra_nhg_check_valid(struct nhg_hash_entry *nhe);
+
+/* Convert nhe depends to a grp context that can be passed around safely */
+extern uint8_t zebra_nhg_nhe2grp(struct nh_grp *grp, struct nhg_hash_entry *nhe,
+				 int size);
+
+/* Dataplane install/uninstall */
+extern void zebra_nhg_install_kernel(struct nhg_hash_entry *nhe);
+extern void zebra_nhg_uninstall_kernel(struct nhg_hash_entry *nhe);
+extern void zebra_interface_nhg_reinstall(struct interface *ifp);
+
+/* Forward ref of dplane update context type */
+struct zebra_dplane_ctx;
+extern void zebra_nhg_dplane_result(struct zebra_dplane_ctx *ctx);
+
+
+/* Sweep the nhg hash tables for old entries on restart */
+extern void zebra_nhg_sweep_table(struct hash *hash);
+
+/*
+ * We are shutting down but the nexthops should be kept
+ * as that -r has been specified and we don't want to delete
+ * the routes unintentionally
+ */
+extern void zebra_nhg_mark_keep(void);
+
+/* Nexthop resolution processing */
+struct route_entry; /* Forward ref to avoid circular includes */
+extern int nexthop_active_update(struct route_node *rn, struct route_entry *re);
+
+#ifdef _FRR_ATTRIBUTE_PRINTFRR
+#pragma FRR printfrr_ext "%pNG" (const struct nhg_hash_entry *)
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* __ZEBRA_NHG_H__ */