lib: Add nexthop-group cli

Add a nexthop-group cli:

nexthop-group NAME
  nexthop A
  nexthop B
  nexthop C
!

This will allow interested parties to hook into the cli for
nexthops.  Users can add callback functions for add/delete
of a nexthop group as well as add/delete of each individual
nexthop.

Future work( PBR and static routes ) will take advantage
of this.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

4 files changed, 396 insertions, 8 deletions

diff --git a/lib/nexthop.c b/lib/nexthop.c
index cee34e85c..fb7ccc169 100644
--- a/lib/nexthop.c
+++ b/lib/nexthop.c
@@ -163,6 +163,57 @@ void nexthops_free(struct nexthop *nexthop)
 	}
 }
 
+bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2)
+{
+	if (nh1 && !nh2)
+		return false;
+
+	if (!nh1 && nh2)
+		return false;
+
+	if (nh1 == nh2)
+		return true;
+
+	if (nh1->vrf_id != nh2->vrf_id)
+		return false;
+
+	if (nh1->type != nh2->type)
+		return false;
+
+	switch (nh1->type) {
+	case NEXTHOP_TYPE_IFINDEX:
+		if (nh1->ifindex != nh2->ifindex)
+			return false;
+		break;
+	case NEXTHOP_TYPE_IPV4:
+		if (nh1->gate.ipv4.s_addr != nh2->gate.ipv4.s_addr)
+			return false;
+		break;
+	case NEXTHOP_TYPE_IPV4_IFINDEX:
+		if (nh1->gate.ipv4.s_addr != nh2->gate.ipv4.s_addr)
+			return false;
+		if (nh1->ifindex != nh2->ifindex)
+			return false;
+		break;
+	case NEXTHOP_TYPE_IPV6:
+		if (memcmp(&nh1->gate.ipv6, &nh2->gate.ipv6, 16))
+			return false;
+		break;
+	case NEXTHOP_TYPE_IPV6_IFINDEX:
+		if (memcmp(&nh1->gate.ipv6, &nh2->gate.ipv6, 16))
+			return false;
+		if (nh1->ifindex != nh2->ifindex)
+			return false;
+		break;
+	case NEXTHOP_TYPE_BLACKHOLE:
+		if (nh1->bh_type != nh2->bh_type)
+			return false;
+		break;
+	}
+
+	return true;
+}
+
 /* Update nexthop with label information. */
 void nexthop_add_labels(struct nexthop *nexthop, enum lsp_types_t type,
 			u_int8_t num_labels, mpls_label_t *label)
diff --git a/lib/nexthop.h b/lib/nexthop.h
index 0ca8a0063..568243d3a 100644
--- a/lib/nexthop.h
+++ b/lib/nexthop.h
@@ -118,6 +118,8 @@ void nexthop_add_labels(struct nexthop *, enum lsp_types_t, u_int8_t,
 			mpls_label_t *);
 void nexthop_del_labels(struct nexthop *);
 
+extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
+
 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 extern int nexthop_same_no_recurse(const struct nexthop *next1,
 				   const struct nexthop *next2);
diff --git a/lib/nexthop_group.c b/lib/nexthop_group.c
index e7f10487d..2012fbdbe 100644
--- a/lib/nexthop_group.c
+++ b/lib/nexthop_group.c
@@ -19,6 +19,7 @@
  */
 #include <zebra.h>
 
+#include <vrf.h>
 #include <nexthop.h>
 #include <nexthop_group.h>
 #include <vty.h>
@@ -28,6 +29,56 @@
 #include "lib/nexthop_group_clippy.c"
 #endif
 
+DEFINE_MTYPE_STATIC(LIB, NEXTHOP_GROUP, "Nexthop Group")
+
+struct nexthop_group_hooks {
+	void (*new)(const char *name);
+	void (*add_nexthop)(const struct nexthop_group_cmd *nhg,
+			    const struct nexthop *nhop);
+	void (*del_nexthop)(const struct nexthop_group_cmd *nhg,
+			    const struct nexthop *nhop);
+	void (*delete)(const char *name);
+};
+
+static struct nexthop_group_hooks nhg_hooks;
+
+static inline int
+nexthop_group_cmd_compare(const struct nexthop_group_cmd *nhgc1,
+			  const struct nexthop_group_cmd *nhgc2);
+RB_GENERATE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
+	    nexthop_group_cmd_compare)
+
+struct nhgc_entry_head nhgc_entries;
+
+static inline int
+nexthop_group_cmd_compare(const struct nexthop_group_cmd *nhgc1,
+			  const struct nexthop_group_cmd *nhgc2)
+{
+	return strcmp(nhgc1->name, nhgc2->name);
+}
+
+struct nexthop *nexthop_exists(struct nexthop_group *nhg, struct nexthop *nh)
+{
+	struct nexthop *nexthop;
+
+	for (nexthop = nhg->nexthop; nexthop; nexthop = nexthop->next) {
+		if (nexthop_same(nh, nexthop))
+			return nexthop;
+	}
+
+	return NULL;
+}
+
+struct nexthop_group *nexthop_group_new(void)
+{
+	return XCALLOC(MTYPE_NEXTHOP_GROUP, sizeof(struct nexthop_group));
+}
+
+void nexthop_group_delete(struct nexthop_group **nhg)
+{
+	XFREE(MTYPE_NEXTHOP_GROUP, *nhg);
+}
+
 /* Add nexthop to the end of a nexthop list.  */
 void nexthop_add(struct nexthop **target, struct nexthop *nexthop)
 {
@@ -42,6 +93,27 @@ void nexthop_add(struct nexthop **target, struct nexthop *nexthop)
 	nexthop->prev = last;
 }
 
+/* Delete nexthop from a nexthop list.  */
+void nexthop_del(struct nexthop_group *nhg, struct nexthop *nh)
+{
+	struct nexthop *nexthop;
+
+	for (nexthop = nhg->nexthop; nexthop; nexthop = nexthop->next) {
+		if (nexthop_same(nh, nexthop))
+			break;
+	}
+
+	assert(nexthop);
+
+	if (nexthop->prev)
+		nexthop->prev->next = nexthop->next;
+	else
+		nhg->nexthop = nexthop->next;
+
+	if (nexthop->next)
+		nexthop->next->prev = nexthop->prev;
+}
+
 void copy_nexthops(struct nexthop **tnh, struct nexthop *nh,
 		   struct nexthop *rparent)
 {
@@ -71,12 +143,169 @@ void copy_nexthops(struct nexthop **tnh, struct nexthop *nh,
 	}
 }
 
-DEFPY (nexthop_group,
-       nexthop_group_cmd,
-       "nexthop-group NAME",
-       "Enter into the nexthop-group submode\n"
-       "Specify the NAME of the nexthop-group\n")
+static void nhgc_delete_nexthops(struct nexthop_group_cmd *nhgc)
+{
+	struct nexthop *nexthop;
+
+	nexthop = nhgc->nhg.nexthop;
+	while (nexthop) {
+		struct nexthop *next = nexthop_next(nexthop);
+
+		if (nhg_hooks.del_nexthop)
+			nhg_hooks.del_nexthop(nhgc, nexthop);
+
+		nexthop_free(nexthop);
+
+		nexthop = next;
+	}
+}
+
+static struct nexthop_group_cmd *nhgc_find(const char *name)
+{
+	struct nexthop_group_cmd find;
+
+	strlcpy(find.name, name, sizeof(find.name));
+
+	return RB_FIND(nhgc_entry_head, &nhgc_entries, &find);
+}
+
+static struct nexthop_group_cmd *nhgc_get(const char *name)
+{
+	struct nexthop_group_cmd *nhgc;
+
+	nhgc = nhgc_find(name);
+	if (!nhgc) {
+		nhgc = XCALLOC(MTYPE_TMP, sizeof(*nhgc));
+		strlcpy(nhgc->name, name, sizeof(nhgc->name));
+
+		QOBJ_REG(nhgc, nexthop_group_cmd);
+		RB_INSERT(nhgc_entry_head, &nhgc_entries, nhgc);
+
+		if (nhg_hooks.new)
+			nhg_hooks.new(name);
+	}
+
+	return nhgc;
+}
+
+static void nhgc_delete(struct nexthop_group_cmd *nhgc)
 {
+	nhgc_delete_nexthops(nhgc);
+
+	if (nhg_hooks.delete)
+		nhg_hooks.delete(nhgc->name);
+
+	RB_REMOVE(nhgc_entry_head, &nhgc_entries, nhgc);
+}
+
+DEFINE_QOBJ_TYPE(nexthop_group_cmd)
+
+DEFUN_NOSH(nexthop_group, nexthop_group_cmd, "nexthop-group NAME",
+	   "Enter into the nexthop-group submode\n"
+	   "Specify the NAME of the nexthop-group\n")
+{
+	const char *nhg_name = argv[1]->arg;
+	struct nexthop_group_cmd *nhgc = NULL;
+
+	nhgc = nhgc_get(nhg_name);
+	VTY_PUSH_CONTEXT(NH_GROUP_NODE, nhgc);
+
+	return CMD_SUCCESS;
+}
+
+DEFUN_NOSH(no_nexthop_group, no_nexthop_group_cmd, "no nexthop-group NAME",
+	   NO_STR
+	   "Delete the nexthop-group\n"
+	   "Specify the NAME of the nexthop-group\n")
+{
+	const char *nhg_name = argv[2]->arg;
+	struct nexthop_group_cmd *nhgc = NULL;
+
+	nhgc = nhgc_find(nhg_name);
+	if (nhgc)
+		nhgc_delete(nhgc);
+
+	return CMD_SUCCESS;
+}
+
+DEFPY(ecmp_nexthops, ecmp_nexthops_cmd,
+      "[no] nexthop <A.B.C.D|X:X::X:X>$addr [INTERFACE]$intf [nexthop-vrf NAME$name]",
+      NO_STR
+      "Specify one of the nexthops in this ECMP group\n"
+      "v4 Address\n"
+      "v6 Address\n"
+      "Interface to use\n"
+      "If the nexthop is in a different vrf tell us\n"
+      "The nexthop-vrf Name\n")
+{
+	VTY_DECLVAR_CONTEXT(nexthop_group_cmd, nhgc);
+	struct vrf *vrf;
+	struct nexthop nhop;
+	struct nexthop *nh;
+
+	if (name)
+		vrf = vrf_lookup_by_name(name);
+	else
+		vrf = vrf_lookup_by_id(VRF_DEFAULT);
+
+	if (!vrf) {
+		vty_out(vty, "Specified: %s is non-existent\n", name);
+		return CMD_WARNING;
+	}
+
+	memset(&nhop, 0, sizeof(nhop));
+	nhop.vrf_id = vrf->vrf_id;
+
+	if (addr->sa.sa_family == AF_INET) {
+		nhop.gate.ipv4.s_addr = addr->sin.sin_addr.s_addr;
+		if (intf) {
+			nhop.type = NEXTHOP_TYPE_IPV4_IFINDEX;
+			nhop.ifindex = ifname2ifindex(intf, vrf->vrf_id);
+			if (nhop.ifindex == IFINDEX_INTERNAL) {
+				vty_out(vty,
+					"Specified Intf %s does not exist in vrf: %s\n",
+					intf, vrf->name);
+				return CMD_WARNING;
+			}
+		} else
+			nhop.type = NEXTHOP_TYPE_IPV4;
+	} else {
+		memcpy(&nhop.gate.ipv6, &addr->sin6.sin6_addr, 16);
+		if (intf) {
+			nhop.type = NEXTHOP_TYPE_IPV6_IFINDEX;
+			nhop.ifindex = ifname2ifindex(intf, vrf->vrf_id);
+			if (nhop.ifindex == IFINDEX_INTERNAL) {
+				vty_out(vty,
+					"Specified Intf %s does not exist in vrf: %s\n",
+					intf, vrf->name);
+				return CMD_WARNING;
+			}
+		} else
+			nhop.type = NEXTHOP_TYPE_IPV6;
+	}
+
+	nh = nexthop_exists(&nhgc->nhg, &nhop);
+
+	if (no) {
+		if (nh) {
+			nexthop_del(&nhgc->nhg, nh);
+
+			if (nhg_hooks.del_nexthop)
+				nhg_hooks.del_nexthop(nhgc, nh);
+
+			nexthop_free(nh);
+		}
+	} else if (!nh) {
+		/* must be adding new nexthop since !no and !nexthop_exists */
+		nh = nexthop_new();
+
+		memcpy(nh, &nhop, sizeof(nhop));
+		nexthop_add(&nhgc->nhg.nexthop, nh);
+
+		if (nhg_hooks.add_nexthop)
+			nhg_hooks.add_nexthop(nhgc, nh);
+	}
+
 	return CMD_SUCCESS;
 }
 
@@ -88,13 +317,85 @@ struct cmd_node nexthop_group_node = {
 
 static int nexthop_group_write(struct vty *vty)
 {
-	vty_out(vty, "!\n");
+	struct nexthop_group_cmd *nhgc;
+	struct nexthop *nh;
+	struct vrf *vrf;
+
+	RB_FOREACH (nhgc, nhgc_entry_head, &nhgc_entries) {
+		char buf[100];
+
+		vty_out(vty, "nexthop-group %s\n", nhgc->name);
+
+		for (nh = nhgc->nhg.nexthop; nh; nh = nh->next) {
+
+			vty_out(vty, "  nexthop ");
+
+			switch (nh->type) {
+			case NEXTHOP_TYPE_IFINDEX:
+				vty_out(vty, "%s",
+					ifindex2ifname(nh->ifindex,
+						       nh->vrf_id));
+				break;
+			case NEXTHOP_TYPE_IPV4:
+				vty_out(vty, "%s", inet_ntoa(nh->gate.ipv4));
+				break;
+			case NEXTHOP_TYPE_IPV4_IFINDEX:
+				vty_out(vty, "%s %s", inet_ntoa(nh->gate.ipv4),
+					ifindex2ifname(nh->ifindex,
+						       nh->vrf_id));
+				break;
+			case NEXTHOP_TYPE_IPV6:
+				vty_out(vty, "%s",
+					inet_ntop(AF_INET6, &nh->gate.ipv6, buf,
+						  sizeof(buf)));
+				break;
+			case NEXTHOP_TYPE_IPV6_IFINDEX:
+				vty_out(vty, "%s %s",
+					inet_ntop(AF_INET6, &nh->gate.ipv6, buf,
+						  sizeof(buf)),
+					ifindex2ifname(nh->ifindex,
+						       nh->vrf_id));
+				break;
+			case NEXTHOP_TYPE_BLACKHOLE:
+				break;
+			}
+
+			if (nh->vrf_id) {
+				vrf = vrf_lookup_by_id(nh->vrf_id);
+				vty_out(vty, " nexthop-vrf %s", vrf->name);
+			}
+			vty_out(vty, "\n");
+		}
+		vty_out(vty, "!\n");
+	}
 
 	return 1;
 }
 
-void nexthop_group_init(void)
+void nexthop_group_init(void (*new)(const char *name),
+			void (*add_nexthop)(const struct nexthop_group_cmd *nhg,
+					    const struct nexthop *nhop),
+			void (*del_nexthop)(const struct nexthop_group_cmd *nhg,
+					    const struct nexthop *nhop),
+			void (*delete)(const char *name))
 {
+	RB_INIT(nhgc_entry_head, &nhgc_entries);
+
 	install_node(&nexthop_group_node, nexthop_group_write);
 	install_element(CONFIG_NODE, &nexthop_group_cmd);
+	install_element(CONFIG_NODE, &no_nexthop_group_cmd);
+
+	install_default(NH_GROUP_NODE);
+	install_element(NH_GROUP_NODE, &ecmp_nexthops_cmd);
+
+	memset(&nhg_hooks, 0, sizeof(nhg_hooks));
+
+	if (new)
+		nhg_hooks.new = new;
+	if (add_nexthop)
+		nhg_hooks.add_nexthop = add_nexthop;
+	if (del_nexthop)
+		nhg_hooks.del_nexthop = del_nexthop;
+	if (delete)
+		nhg_hooks.delete = delete;
 }
diff --git a/lib/nexthop_group.h b/lib/nexthop_group.h
index 561fe9642..563799dc8 100644
--- a/lib/nexthop_group.h
+++ b/lib/nexthop_group.h
@@ -33,9 +33,11 @@ struct nexthop_group {
 	struct nexthop *nexthop;
 };
 
-void nexthop_group_init(void);
+struct nexthop_group *nexthop_group_new(void);
+void nexthop_group_delete(struct nexthop_group **nhg);
 
 void nexthop_add(struct nexthop **target, struct nexthop *nexthop);
+void nexthop_del(struct nexthop_group *nhg, struct nexthop *nexthop);
 void copy_nexthops(struct nexthop **tnh, struct nexthop *nh,
 		   struct nexthop *rparent);
 
@@ -51,4 +53,36 @@ void copy_nexthops(struct nexthop **tnh, struct nexthop *nh,
 	(nhop) = (head.nexthop);					\
 	(nhop);								\
 	(nhop) = nexthop_next(nhop)
+
+struct nexthop_group_cmd {
+
+	RB_ENTRY(nexthop_group_cmd) nhgc_entry;
+
+	char name[80];
+
+	struct nexthop_group nhg;
+
+	QOBJ_FIELDS
+};
+RB_HEAD(nhgc_entry_head, nexthp_group_cmd);
+RB_PROTOTYPE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
+	     nexthop_group_cmd_compare)
+DECLARE_QOBJ_TYPE(nexthop_group_cmd)
+
+/*
+ * Initialize nexthop_groups.  If you are interested in when
+ * a nexthop_group is added/deleted/modified, then set the
+ * appropriate callback functions to handle it in your
+ * code
+ */
+void nexthop_group_init(
+	void (*new)(const char *name),
+	void (*add_nexthop)(const struct nexthop_group_cmd *nhgc,
+			    const struct nexthop *nhop),
+	void (*del_nexthop)(const struct nexthop_group_cmd *nhgc,
+			    const struct nexthop *nhop),
+	void (*delete)(const char *name));
+
+extern struct nexthop *nexthop_exists(struct nexthop_group *nhg,
+				      struct nexthop *nh);
 #endif