Take source and destination address into account when determining

the scope.
This fixes a problem when a client with a global address
connects to a server with a private address.
Thanks to Irene Ruengeler in helping me to find the issue.

MFC after: 3 days

1 files changed, 18 insertions, 14 deletions

diff --git a/sys/netinet/sctp_output.c b/sys/netinet/sctp_output.c
index 47a341c..d2ada5d 100644
--- a/sys/netinet/sctp_output.c
+++ b/sys/netinet/sctp_output.c
@@ -5612,7 +5612,8 @@ do_a_abort:
 				stc.laddr_type = SCTP_IPV4_ADDRESS;
 				/* scope_id is only for v6 */
 				stc.scope_id = 0;
-				if (IN4_ISPRIVATE_ADDRESS(&src4->sin_addr)) {
+				if ((IN4_ISPRIVATE_ADDRESS(&src4->sin_addr)) ||
+				    (IN4_ISPRIVATE_ADDRESS(&dst4->sin_addr))) {
 					stc.ipv4_scope = 1;
 				}
 				/* Must use the address in this case */
@@ -5636,16 +5637,18 @@ do_a_abort:
 					stc.local_scope = 0;
 					stc.site_scope = 1;
 					stc.ipv4_scope = 1;
-				} else if (IN6_IS_ADDR_LINKLOCAL(&src6->sin6_addr)) {
+				} else if (IN6_IS_ADDR_LINKLOCAL(&src6->sin6_addr) ||
+				    IN6_IS_ADDR_LINKLOCAL(&dst6->sin6_addr)) {
 					/*
-					 * If the new destination is a
-					 * LINK_LOCAL we must have common
-					 * both site and local scope. Don't
-					 * set local scope though since we
-					 * must depend on the source to be
-					 * added implicitly. We cannot
-					 * assure just because we share one
-					 * link that all links are common.
+					 * If the new destination or source
+					 * is a LINK_LOCAL we must have
+					 * common both site and local scope.
+					 * Don't set local scope though
+					 * since we must depend on the
+					 * source to be added implicitly. We
+					 * cannot assure just because we
+					 * share one link that all links are
+					 * common.
 					 */
 					stc.local_scope = 0;
 					stc.site_scope = 1;
@@ -5661,11 +5664,12 @@ do_a_abort:
 					 * pull out the scope_id from
 					 * incoming pkt
 					 */
-				} else if (IN6_IS_ADDR_SITELOCAL(&src6->sin6_addr)) {
+				} else if (IN6_IS_ADDR_SITELOCAL(&src6->sin6_addr) ||
+				    IN6_IS_ADDR_SITELOCAL(&dst6->sin6_addr)) {
 					/*
-					 * If the new destination is
-					 * SITE_LOCAL then we must have site
-					 * scope in common.
+					 * If the new destination or source
+					 * is SITE_LOCAL then we must have
+					 * site scope in common.
 					 */
 					stc.site_scope = 1;
 				}