ipv6: Refactor update of IPv6 flowi destination address for srcrt (RH) option
There are more than a dozen occurrences of following code in the
IPv6 stack:
if (opt && opt->srcrt) {
struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
ipv6_addr_copy(&final, &fl.fl6_dst);
ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
final_p = &final;
}
Replace those with a helper. Note that the helper overrides final_p
in all cases. This is ok as final_p was previously initialized to
NULL when declared.
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 8a659f92..853a633 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -874,3 +874,27 @@
return opt;
}
+/**
+ * fl6_update_dst - update flowi destination address with info given
+ * by srcrt option, if any.
+ *
+ * @fl: flowi for which fl6_dst is to be updated
+ * @opt: struct ipv6_txoptions in which to look for srcrt opt
+ * @orig: copy of original fl6_dst address if modified
+ *
+ * Returns NULL if no txoptions or no srcrt, otherwise returns orig
+ * and initial value of fl->fl6_dst set in orig
+ */
+struct in6_addr *fl6_update_dst(struct flowi *fl,
+ const struct ipv6_txoptions *opt,
+ struct in6_addr *orig)
+{
+ if (!opt || !opt->srcrt)
+ return NULL;
+
+ ipv6_addr_copy(orig, &fl->fl6_dst);
+ ipv6_addr_copy(&fl->fl6_dst, ((struct rt0_hdr *)opt->srcrt)->addr);
+ return orig;
+}
+
+EXPORT_SYMBOL_GPL(fl6_update_dst);