sadb_x_sa2
sa2 = skb_put(skb, sizeof(struct sadb_x_sa2));
sa2->sadb_x_sa2_len = sizeof(struct sadb_x_sa2)/sizeof(uint64_t);
const struct sadb_x_sa2 *sa2 = ext_hdrs[SADB_X_EXT_SA2-1];
struct sadb_x_sa2 *sa2;
[SADB_X_EXT_SA2] = (u8) sizeof(struct sadb_x_sa2),
struct sadb_x_sa2 *sa2;
sizeof(struct sadb_x_sa2);