1 files changed, 216 insertions, 0 deletions
diff --git a/bgpd/bgp_community_alias.c b/bgpd/bgp_community_alias.c
new file mode 100644
index 0000000..96dc1ec
--- /dev/null
+++ b/bgpd/bgp_community_alias.c
@@ -0,0 +1,216 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* BGP community, large-community aliasing.
+ *
+ * Copyright (C) 2021 Donatas Abraitis <donatas.abraitis@gmail.com>
+ */
+
+#include "zebra.h"
+
+#include "memory.h"
+#include "lib/jhash.h"
+#include "frrstr.h"
+
+#include "bgpd/bgpd.h"
+#include "bgpd/bgp_community_alias.h"
+
+static struct hash *bgp_ca_alias_hash;
+static struct hash *bgp_ca_community_hash;
+
+static unsigned int bgp_ca_community_hash_key(const void *p)
+{
+	const struct community_alias *ca = p;
+
+	return jhash(ca->community, sizeof(ca->community), 0);
+}
+
+static bool bgp_ca_community_hash_cmp(const void *p1, const void *p2)
+{
+	const struct community_alias *ca1 = p1;
+	const struct community_alias *ca2 = p2;
+
+	return (strcmp(ca1->community, ca2->community) == 0);
+}
+
+static unsigned int bgp_ca_alias_hash_key(const void *p)
+{
+	const struct community_alias *ca = p;
+
+	return jhash(ca->alias, sizeof(ca->alias), 0);
+}
+
+static bool bgp_ca_alias_hash_cmp(const void *p1, const void *p2)
+{
+	const struct community_alias *ca1 = p1;
+	const struct community_alias *ca2 = p2;
+
+	return (strcmp(ca1->alias, ca2->alias) == 0);
+}
+
+static void *bgp_community_alias_alloc(void *p)
+{
+	const struct community_alias *ca = p;
+	struct communtiy_alias *new;
+
+	new = XCALLOC(MTYPE_COMMUNITY_ALIAS, sizeof(struct community_alias));
+	memcpy(new, ca, sizeof(struct community_alias));
+
+	return new;
+}
+
+void bgp_community_alias_init(void)
+{
+	bgp_ca_community_hash = hash_create(bgp_ca_community_hash_key,
+					       bgp_ca_community_hash_cmp,
+					       "BGP community alias (community)");
+	bgp_ca_alias_hash =
+		hash_create(bgp_ca_alias_hash_key, bgp_ca_alias_hash_cmp,
+			    "BGP community alias (alias)");
+}
+
+static void bgp_ca_free(void *ca)
+{
+	XFREE(MTYPE_COMMUNITY_ALIAS, ca);
+}
+
+void bgp_community_alias_finish(void)
+{
+	hash_clean_and_free(&bgp_ca_community_hash, bgp_ca_free);
+	hash_clean_and_free(&bgp_ca_alias_hash, bgp_ca_free);
+}
+
+static void bgp_community_alias_show_iterator(struct hash_bucket *hb,
+					      struct vty *vty)
+{
+	struct community_alias *ca = hb->data;
+
+	vty_out(vty, "bgp community alias %s %s\n", ca->community, ca->alias);
+}
+
+int bgp_community_alias_write(struct vty *vty)
+{
+	hash_iterate(bgp_ca_community_hash,
+		     (void (*)(struct hash_bucket *,
+			       void *))bgp_community_alias_show_iterator,
+		     vty);
+	return 1;
+}
+
+void bgp_ca_community_insert(struct community_alias *ca)
+{
+	(void)hash_get(bgp_ca_community_hash, ca, bgp_community_alias_alloc);
+}
+
+void bgp_ca_alias_insert(struct community_alias *ca)
+{
+	(void)hash_get(bgp_ca_alias_hash, ca, bgp_community_alias_alloc);
+}
+
+void bgp_ca_community_delete(struct community_alias *ca)
+{
+	struct community_alias *data = hash_release(bgp_ca_community_hash, ca);
+
+	XFREE(MTYPE_COMMUNITY_ALIAS, data);
+}
+
+void bgp_ca_alias_delete(struct community_alias *ca)
+{
+	struct community_alias *data = hash_release(bgp_ca_alias_hash, ca);
+
+	XFREE(MTYPE_COMMUNITY_ALIAS, data);
+}
+
+struct community_alias *bgp_ca_community_lookup(struct community_alias *ca)
+{
+	return hash_lookup(bgp_ca_community_hash, ca);
+}
+
+struct community_alias *bgp_ca_alias_lookup(struct community_alias *ca)
+{
+	return hash_lookup(bgp_ca_alias_hash, ca);
+}
+
+const char *bgp_community2alias(char *community)
+{
+	struct community_alias ca;
+	struct community_alias *find;
+
+	memset(&ca, 0, sizeof(ca));
+	strlcpy(ca.community, community, sizeof(ca.community));
+
+	find = bgp_ca_community_lookup(&ca);
+	if (find)
+		return find->alias;
+
+	return community;
+}
+
+const char *bgp_alias2community(char *alias)
+{
+	struct community_alias ca;
+	struct community_alias *find;
+
+	memset(&ca, 0, sizeof(ca));
+	strlcpy(ca.alias, alias, sizeof(ca.alias));
+
+	find = bgp_ca_alias_lookup(&ca);
+	if (find)
+		return find->community;
+
+	return alias;
+}
+
+/* Communities structs have `->str` which is used
+ * for vty outputs and extended BGP community lists
+ * with regexp.
+ * This is a helper to convert already aliased version
+ * of communities into numerical-only format.
+ */
+char *bgp_alias2community_str(const char *str)
+{
+	char **aliases;
+	char *comstr;
+	int num, i;
+
+	frrstr_split(str, " ", &aliases, &num);
+	const char *communities[num];
+
+	for (i = 0; i < num; i++)
+		communities[i] = bgp_alias2community(aliases[i]);
+
+	comstr = frrstr_join(communities, num, " ");
+
+	for (i = 0; i < num; i++)
+		XFREE(MTYPE_TMP, aliases[i]);
+	XFREE(MTYPE_TMP, aliases);
+
+	return comstr;
+}
+
+static int bgp_community_alias_vector_walker(struct hash_bucket *bucket,
+					     void *data)
+{
+	vector *comps = data;
+	struct community_alias *alias = bucket->data;
+
+	vector_set(*comps, XSTRDUP(MTYPE_COMPLETION, alias->alias));
+
+	return 1;
+}
+
+static void bgp_community_alias_cmd_completion(vector comps,
+					       struct cmd_token *token)
+{
+	hash_walk(bgp_ca_alias_hash, bgp_community_alias_vector_walker, &comps);
+}
+
+static const struct cmd_variable_handler community_alias_handlers[] = {
+	{.varname = "alias_name",
+	 .completions = bgp_community_alias_cmd_completion},
+	{.tokenname = "ALIAS_NAME",
+	 .completions = bgp_community_alias_cmd_completion},
+	{.completions = NULL}};
+
+void bgp_community_alias_command_completion_setup(void)
+{
+	cmd_variable_handler_register(community_alias_handlers);
+}