nh-encap: Support cloning rtnl_nh_encap in rtnl_route_nh_clone

Signed-off-by: Christoph Paasch <[email protected]>

Author: cpaasch-oai

include/netlink/route/nexthop.h

@@ -62,6 +62,7 @@ extern int rtnl_route_nh_str2flags(const char *);
  */
 extern struct rtnl_nh_encap *rtnl_nh_encap_alloc(void);
 extern void rtnl_nh_encap_free(struct rtnl_nh_encap *nh_encap);
+extern struct rtnl_nh_encap *rtnl_nh_encap_clone(struct rtnl_nh_encap *src);
 
 extern int rtnl_nh_encap_mpls(struct rtnl_nh_encap *nh_encap,
 			      struct nl_addr *dst, uint8_t ttl);

lib/route/nexthop-encap.h

@@ -8,6 +8,7 @@ struct nh_encap_ops {
 	int (*parse_msg)(struct nlattr *nla, struct rtnl_nexthop *rtnh);
 
 	int (*compare)(void *a, void *b);
+	void *(*clone)(void *priv);
 
 	void (*dump)(void *priv, struct nl_dump_params *dp);
 	void (*destructor)(void *priv);

lib/route/nexthop.c

@@ -83,6 +83,13 @@ struct rtnl_nexthop *rtnl_route_nh_clone(struct rtnl_nexthop *src)
 			return NULL;
 	}
 
+	/* Clone encapsulation information if present */
+	if (src->rtnh_encap) {
+		nh->rtnh_encap = rtnl_nh_encap_clone(src->rtnh_encap);
+		if (!nh->rtnh_encap)
+			return NULL;
+	}
+
 	return _nl_steal_pointer(&nh);
 }
 

lib/route/nh.c

@@ -669,6 +669,27 @@ void rtnl_nh_encap_free(struct rtnl_nh_encap *nh_encap)
 	free(nh_encap);
 }
 
+struct rtnl_nh_encap *rtnl_nh_encap_clone(struct rtnl_nh_encap *src)
+{
+	_nl_auto_rtnl_nh_encap struct rtnl_nh_encap *new_encap = NULL;
+
+	if (!src)
+		return NULL;
+
+	new_encap = rtnl_nh_encap_alloc();
+	if (!new_encap)
+		return NULL;
+
+	new_encap->ops = src->ops;
+	if (new_encap->ops) {
+		new_encap->priv = new_encap->ops->clone(src->priv);
+		if (!new_encap->priv)
+			return NULL;
+	}
+
+	return _nl_steal_pointer(&new_encap);
+}
+
 /*
  * Retrieve the encapsulation associated with a nexthop if any.
  */

lib/route/nh_encap_mpls.c

@@ -49,6 +49,24 @@ static void mpls_encap_destructor(void *priv)
 	nl_addr_put(encap_info->dst);
 }
 
+static void *mpls_encap_clone(void *priv)
+{
+	struct mpls_iptunnel_encap *src = priv;
+	struct mpls_iptunnel_encap *clone;
+
+	if (!src)
+		return NULL;
+
+	clone = calloc(1, sizeof(*clone));
+	if (!clone)
+		return NULL;
+
+	clone->dst = nl_addr_get(src->dst);
+	clone->ttl = src->ttl;
+
+	return clone;
+}
+
 static struct nla_policy mpls_encap_policy[MPLS_IPTUNNEL_MAX + 1] = {
 	[MPLS_IPTUNNEL_DST] = { .type = NLA_U32 },
 	[MPLS_IPTUNNEL_TTL] = { .type = NLA_U8 },
@@ -108,6 +126,7 @@ struct nh_encap_ops mpls_encap_ops = {
 	.build_msg = mpls_encap_build_msg,
 	.parse_msg = mpls_encap_parse_msg,
 	.compare = mpls_encap_compare,
+	.clone = mpls_encap_clone,
 	.dump = mpls_encap_dump,
 	.destructor = mpls_encap_destructor,
 };

libnl-route-3.sym

@@ -1372,6 +1372,7 @@ global:
 	rtnl_link_is_bond;
 	rtnl_nh_add;
 	rtnl_nh_encap_alloc;
+	rtnl_nh_encap_clone;
 	rtnl_nh_encap_free;
 	rtnl_nh_encap_mpls;
 	rtnl_nh_get_encap_mpls_dst;

tests/cksuite-route-nexthop.c

@@ -36,8 +36,10 @@ START_TEST(test_route_nexthop_api_set_get_all)
 	_nl_auto_nl_addr struct nl_addr *via6 = NULL;
 	_nl_auto_nl_addr struct nl_addr *mpls = NULL;
 	_nl_auto_rtnl_nexthop struct rtnl_nexthop *clone = NULL;
+	_nl_auto_rtnl_nexthop struct rtnl_nexthop *clone_with_encap = NULL;
 	struct rtnl_nh_encap *encap = NULL;
 	struct rtnl_nh_encap *got = NULL;
+	struct rtnl_nh_encap *encap_clone = NULL;
 	uint32_t realms = 0xAABBCCDDu;
 	char flags_buf[64];
 	int flags_parsed;
@@ -141,6 +143,28 @@ START_TEST(test_route_nexthop_api_set_get_all)
 	ck_assert_ptr_nonnull(rtnl_nh_get_encap_mpls_dst(got));
 	ck_assert_int_eq(rtnl_nh_get_encap_mpls_ttl(got), 64);
 
+	/* Exercise rtnl_nh_encap_clone() directly */
+	encap_clone = rtnl_nh_encap_clone(encap);
+	ck_assert_ptr_nonnull(encap_clone);
+	ck_assert_ptr_nonnull(rtnl_nh_get_encap_mpls_dst(encap_clone));
+	ck_assert_int_eq(
+		nl_addr_cmp(rtnl_nh_get_encap_mpls_dst(encap_clone), mpls), 0);
+	ck_assert_uint_eq(rtnl_nh_get_encap_mpls_ttl(encap_clone), 64);
+	/* Free the cloned encap explicitly */
+	rtnl_nh_encap_free(encap_clone);
+	encap_clone = NULL;
+
+	/* Exercise nexthop clone with encap: encap should be deep-cloned */
+	clone_with_encap = rtnl_route_nh_clone(nh);
+	ck_assert_ptr_nonnull(clone_with_encap);
+	encap_clone = rtnl_route_nh_get_encap(clone_with_encap);
+	ck_assert_ptr_nonnull(encap_clone);
+	/* The encap on the clone must not be the same pointer */
+	ck_assert_ptr_ne(encap_clone, encap);
+	ck_assert_int_eq(
+		nl_addr_cmp(rtnl_nh_get_encap_mpls_dst(encap_clone), mpls), 0);
+	ck_assert_uint_eq(rtnl_nh_get_encap_mpls_ttl(encap_clone), 64);
+
 	/* Clear encap and verify it is removed */
 	ck_assert_int_eq(rtnl_route_nh_set_encap(nh, NULL), 0);
 	ck_assert_ptr_eq(rtnl_route_nh_get_encap(nh), NULL);