We introduce two callbacks used for customizing the creation/destruction of
a SRv6 behavior. Such callbacks are defined in the new struct
seg6_local_lwtunnel_ops and hereafter we provide a brief description of
them:
- build_state(...): used for calling the custom constructor of the
behavior during its initialization phase and after all the attributes
have been parsed successfully;
- destroy_state(...): used for calling the custom destructor of the
behavior before it is completely destroyed.
Signed-off-by: Andrea Mayer <andrea.ma...@uniroma2.it>
---
net/ipv6/seg6_local.c | 64 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 64 insertions(+)
diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c
index 63a82e2fdea9..4b0f155d641d 100644
--- a/net/ipv6/seg6_local.c
+++ b/net/ipv6/seg6_local.c
@@ -33,11 +33,23 @@
struct seg6_local_lwt;
+typedef int (*slwt_build_state_t)(struct seg6_local_lwt *slwt, const void *cfg,
+ struct netlink_ext_ack *extack);
+typedef void (*slwt_destroy_state_t)(struct seg6_local_lwt *slwt);
+
+/* callbacks used for customizing the creation and destruction of a behavior */
+struct seg6_local_lwtunnel_ops {
+ slwt_build_state_t build_state;
+ slwt_destroy_state_t destroy_state;
+};
+
struct seg6_action_desc {
int action;
unsigned long attrs;
int (*input)(struct sk_buff *skb, struct seg6_local_lwt *slwt);
int static_headroom;
+
+ struct seg6_local_lwtunnel_ops slwt_ops;
};
struct bpf_lwt_prog {
@@ -1015,6 +1027,45 @@ static void destroy_attrs(struct seg6_local_lwt *slwt)
__destroy_attrs(attrs, 0, SEG6_LOCAL_MAX + 1, slwt);
}
+/* call the custom constructor of the behavior during its initialization phase
+ * and after that all its attributes have been parsed successfully.
+ */
+static int
+seg6_local_lwtunnel_build_state(struct seg6_local_lwt *slwt, const void *cfg,
+ struct netlink_ext_ack *extack)
+{
+ slwt_build_state_t build_func;
+ struct seg6_action_desc *desc;
+ int err = 0;
+
+ desc = slwt->desc;
+ if (!desc)
+ return -EINVAL;
+
+ build_func = desc->slwt_ops.build_state;
+ if (build_func)
+ err = build_func(slwt, cfg, extack);
+
+ return err;
+}
+
+/* call the custom destructor of the behavior which is invoked before the
+ * tunnel is going to be destroyed.
+ */
+static void seg6_local_lwtunnel_destroy_state(struct seg6_local_lwt *slwt)
+{
+ slwt_destroy_state_t destroy_func;
+ struct seg6_action_desc *desc;
+
+ desc = slwt->desc;
+ if (!desc)
+ return;
+
+ destroy_func = desc->slwt_ops.destroy_state;
+ if (destroy_func)
+ destroy_func(slwt);
+}
+
static int parse_nla_action(struct nlattr **attrs, struct seg6_local_lwt *slwt)
{
struct seg6_action_param *param;
@@ -1090,8 +1141,16 @@ static int seg6_local_build_state(struct net *net,
struct nlattr *nla,
err = parse_nla_action(tb, slwt);
if (err < 0)
+ /* In case of error, the parse_nla_action() takes care of
+ * releasing resources which have been acquired during the
+ * processing of attributes.
+ */
goto out_free;
+ err = seg6_local_lwtunnel_build_state(slwt, cfg, extack);
+ if (err < 0)
+ goto free_attrs;
+
newts->type = LWTUNNEL_ENCAP_SEG6_LOCAL;
newts->flags = LWTUNNEL_STATE_INPUT_REDIRECT;
newts->headroom = slwt->headroom;
@@ -1100,6 +1159,9 @@ static int seg6_local_build_state(struct net *net, struct
nlattr *nla,
return 0;
+free_attrs:
+ destroy_attrs(slwt);
+
out_free:
kfree(newts);
return err;
@@ -1109,6 +1171,8 @@ static void seg6_local_destroy_state(struct
lwtunnel_state *lwt)
{
struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
+ seg6_local_lwtunnel_destroy_state(slwt);
+
destroy_attrs(slwt);
return;
--
2.20.1
