route: add support for getting permanent mac address of link.

thom311 · Sep 12, 2024 · b292cdd · b292cdd
1 parent afafe78
commit b292cdd
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Showing 5 changed files with 51 additions and 0 deletions.
diff --git a/doc/route.txt b/doc/route.txt
@@ -394,6 +394,17 @@ void rtnl_link_set_addr(struct rtnl_link *link, struct nl_addr *addr);
 struct nl_addr *rtnl_link_get_addr(struct rtnl_link *link);
 -----
 
+[[link_attr_permaddr]]
+==== Permanent address
+The permanent link layer address (e.g. MAC address).
+
+[source,c]
+-----
+#include <netlink/route/link.h>
+
+struct nl_addr *rtnl_link_get_perm_addr(struct rtnl_link *link);
+-----
+
 [[link_attr_broadcast]]
 ==== Broadcast Address
 The link layer broadcast address

diff --git a/include/netlink/route/link.h b/include/netlink/route/link.h
@@ -183,6 +183,8 @@ extern unsigned int rtnl_link_get_arptype(struct rtnl_link *);
 extern void     rtnl_link_set_addr(struct rtnl_link *, struct nl_addr *);
 extern struct nl_addr *rtnl_link_get_addr(struct rtnl_link *);
 
+extern struct nl_addr *rtnl_link_get_perm_addr(struct rtnl_link *);
+
 extern void     rtnl_link_set_broadcast(struct rtnl_link *, struct nl_addr *);
 extern struct nl_addr *rtnl_link_get_broadcast(struct rtnl_link *);
 

diff --git a/lib/route/link.c b/lib/route/link.c
@@ -73,6 +73,7 @@
 #define LINK_ATTR_GSO_MAX_SEGS		((uint64_t) 1 << 37)
 #define LINK_ATTR_GSO_MAX_SIZE		((uint64_t) 1 << 38)
 #define LINK_ATTR_LINKINFO_SLAVE_KIND	((uint64_t) 1 << 39)
+#define LINK_ATTR_PERMANENT_ADDR	((uint64_t) 1 << 40)
 
 static struct nl_cache_ops rtnl_link_ops;
 static struct nl_object_ops link_obj_ops;
@@ -271,6 +272,7 @@ static void link_free_data(struct nl_object *c)
 
 		nl_addr_put(link->l_addr);
 		nl_addr_put(link->l_bcast);
+		nl_addr_put(link->l_paddr);
 
 		free(link->l_ifalias);
 		free(link->l_info_kind);
@@ -294,6 +296,7 @@ static int link_clone(struct nl_object *_dst, struct nl_object *_src)
 
 	dst->l_addr = NULL;
 	dst->l_bcast = NULL;
+	dst->l_paddr = NULL;
 	dst->l_info_kind = NULL;
 	dst->l_info_slave_kind = NULL;
 	dst->l_info_ops = NULL;
@@ -313,6 +316,10 @@ static int link_clone(struct nl_object *_dst, struct nl_object *_src)
 		if (!(dst->l_bcast = nl_addr_clone(src->l_bcast)))
 			return -NLE_NOMEM;
 
+	if (src->l_paddr)
+		if (!(dst->l_paddr = nl_addr_clone(src->l_paddr)))
+			return -NLE_NOMEM;
+
 	if (src->l_ifalias)
 		if (!(dst->l_ifalias = strdup(src->l_ifalias)))
 			return -NLE_NOMEM;
@@ -514,6 +521,15 @@ int rtnl_link_info_parse(struct rtnl_link *link, struct nlattr **tb)
 		link->ce_mask |= LINK_ATTR_ADDR;
 	}
 
+	if (tb[IFLA_PERM_ADDRESS]) {
+		link->l_paddr = nl_addr_alloc_attr(tb[IFLA_PERM_ADDRESS], AF_UNSPEC);
+		if (link->l_paddr == NULL)
+			return -NLE_NOMEM;
+		nl_addr_set_family(link->l_paddr,
+				   nl_addr_guess_family(link->l_paddr));
+		link->ce_mask |= LINK_ATTR_PERMANENT_ADDR;
+	}
+
 	if (tb[IFLA_BROADCAST]) {
 		link->l_bcast = nl_addr_alloc_attr(tb[IFLA_BROADCAST],
 						   AF_UNSPEC);
@@ -863,6 +879,9 @@ static void link_dump_line(struct nl_object *obj, struct nl_dump_params *p)
 	if (link->l_addr && !nl_addr_iszero(link->l_addr))
 		nl_dump(p, "%s ", nl_addr2str(link->l_addr, buf, sizeof(buf)));
 
+	if (link->l_paddr && !nl_addr_iszero(link->l_paddr))
+		nl_dump(p, "permanent address %s ", nl_addr2str(link->l_paddr, buf, sizeof(buf)));
+
 	if (link->ce_mask & LINK_ATTR_MASTER) {
 		if (cache) {
 			_nl_auto_rtnl_link struct rtnl_link *master = rtnl_link_get(cache, link->l_master);
@@ -1130,6 +1149,7 @@ static uint64_t link_compare(struct nl_object *_a, struct nl_object *_b,
 	diff |= _DIFF(LINK_ATTR_IFNAME, strcmp(a->l_name, b->l_name));
 	diff |= _DIFF(LINK_ATTR_ADDR, nl_addr_cmp(a->l_addr, b->l_addr));
 	diff |= _DIFF(LINK_ATTR_BRD, nl_addr_cmp(a->l_bcast, b->l_bcast));
+	diff |= _DIFF(LINK_ATTR_PERMANENT_ADDR, nl_addr_cmp(a->l_paddr, b->l_paddr));
 	diff |= _DIFF(LINK_ATTR_IFALIAS, strcmp(a->l_ifalias, b->l_ifalias));
 	diff |= _DIFF(LINK_ATTR_NUM_VF, a->l_num_vf != b->l_num_vf);
 	diff |= _DIFF(LINK_ATTR_PROMISCUITY,
@@ -1565,6 +1585,9 @@ int rtnl_link_fill_info(struct nl_msg *msg, struct rtnl_link *link)
 	if (link->ce_mask & LINK_ATTR_NS_PID)
 		NLA_PUT_U32(msg, IFLA_NET_NS_PID, link->l_ns_pid);
 
+	if (link->ce_mask & LINK_ATTR_PERMANENT_ADDR)
+		NLA_PUT_ADDR(msg, IFLA_PERM_ADDRESS, link->l_paddr);
+
 	return 0;
 
 nla_put_failure:
@@ -2024,6 +2047,19 @@ struct nl_addr *rtnl_link_get_addr(struct rtnl_link *link)
 	return link->ce_mask & LINK_ATTR_ADDR ? link->l_addr : NULL;
 }
 
+/**
+ * Return permanent link layer adress of link object
+ * @arg link		Link object
+ *
+ * @copydoc pointer_lifetime_warning
+ * @route_doc{link_attr_permaddr, Permanent Link Layer Address}
+ * @return Permanent link layer address or NULL if not set.
+ */
+struct nl_addr *rtnl_link_get_perm_addr(struct rtnl_link *link)
+{
+	return link->ce_mask & LINK_ATTR_PERMANENT_ADDR ? link->l_paddr : NULL;
+}
+
 /**
  * Set link layer broadcast address of link object
  * @arg link		Link object

diff --git a/lib/route/nl-route.h b/lib/route/nl-route.h
@@ -43,6 +43,7 @@ struct rtnl_link {
 	uint32_t l_master;
 	struct nl_addr *l_addr;
 	struct nl_addr *l_bcast;
+	struct nl_addr *l_paddr;
 	char l_qdisc[IFQDISCSIZ];
 	struct rtnl_link_map l_map;
 	uint64_t l_stats[RTNL_LINK_STATS_MAX + 1];

diff --git a/libnl-route-3.sym b/libnl-route-3.sym
@@ -1340,4 +1340,5 @@ global:
 	rtnl_link_bond_get_miimon;
 	rtnl_link_bond_get_min_links;
 	rtnl_link_bond_get_mode;
+	rtnl_link_get_perm_addr;
 } libnl_3_10;