xnu-7195.50.7.100.1.tar.gz

[apple/xnu.git] / bsd / netinet6 / nd6_rti.c

diff --git a/bsd/netinet6/nd6_rti.c b/bsd/netinet6/nd6_rti.c
new file mode 100644 (file)
index 0000000..16c2ab3
--- /dev/null
+++ b/bsd/netinet6/nd6_rti.c
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2020 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+#include <kern/zalloc.h>
+#include <net/if.h>
+#include <net/if_var.h>
+#include <netinet/in.h>
+#include <netinet6/in6_var.h>
+#include <netinet6/in6_ifattach.h>
+#include <netinet/ip6.h>
+#include <netinet6/ip6_var.h>
+#include <netinet6/nd6.h>
+#include <netinet6/scope6_var.h>
+#include <sys/mcache.h>
+
+#define NDRTI_ZONE_NAME "nd6_route_info"        /* zone name */
+
+extern lck_mtx_t *nd6_mutex;
+static struct nd_route_info *nd6_rti_lookup(struct nd_route_info *);
+
+static ZONE_DECLARE(ndrti_zone, "nd6_route_info",
+    sizeof(struct nd_route_info), ZC_ZFREE_CLEARMEM);
+
+static boolean_t nd6_rti_list_busy = FALSE;             /* protected by nd6_mutex */
+
+
+void
+nd6_rti_list_wait(const char *func)
+{
+       LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
+       while (nd6_rti_list_busy) {
+               nd6log2(debug, "%s: someone else is operating "
+                   "on rti list. Entering sleep.\n", func);
+               (void) msleep(&nd6_rti_list_busy, nd6_mutex, (PZERO - 1),
+                   func, NULL);
+               LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
+       }
+       nd6_rti_list_busy = TRUE;
+}
+
+void
+nd6_rti_list_signal_done(void)
+{
+       LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
+       nd6_rti_list_busy = FALSE;
+       wakeup(&nd6_rti_list_busy);
+}
+
+struct nd_route_info *
+ndrti_alloc(void)
+{
+       return zalloc_flags(ndrti_zone, Z_WAITOK | Z_ZERO);
+}
+
+void
+ndrti_free(struct nd_route_info *rti)
+{
+       if (!TAILQ_EMPTY(&rti->nd_rti_router_list)) {
+               panic("%s: rti freed with non-empty router list", __func__);
+       }
+       zfree(ndrti_zone, rti);
+}
+
+static struct nd_route_info *
+nd6_rti_lookup(struct nd_route_info *rti)
+{
+       struct nd_route_info *tmp_rti = NULL;
+
+       LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
+
+       TAILQ_FOREACH(tmp_rti, &nd_rti_list, nd_rti_entry) {
+               if (IN6_ARE_ADDR_EQUAL(&tmp_rti->nd_rti_prefix, &rti->nd_rti_prefix) &&
+                   tmp_rti->nd_rti_prefixlen == rti->nd_rti_prefixlen) {
+                       break;
+               }
+       }
+       return tmp_rti;
+}
+
+void
+nd6_rtilist_update(struct nd_route_info *new_rti, struct nd_defrouter *dr)
+{
+       struct nd_route_info *rti = NULL;
+
+       lck_mtx_lock(nd6_mutex);
+       VERIFY(new_rti != NULL && dr != NULL);
+       nd6_rti_list_wait(__func__);
+
+       if ((rti = nd6_rti_lookup(new_rti)) != NULL) {
+               (void)defrtrlist_update(dr, &rti->nd_rti_router_list);
+               /*
+                * The above may have removed an entry from default router list.
+                * If it did and the list is now empty, remove the rti as well.
+                */
+               if (TAILQ_EMPTY(&rti->nd_rti_router_list)) {
+                       TAILQ_REMOVE(&nd_rti_list, rti, nd_rti_entry);
+                       ndrti_free(rti);
+               }
+       } else if (dr->rtlifetime != 0) {
+               rti = ndrti_alloc();
+               TAILQ_INIT(&rti->nd_rti_router_list);
+               rti->nd_rti_prefix = new_rti->nd_rti_prefix;
+               rti->nd_rti_prefixlen = new_rti->nd_rti_prefixlen;
+               (void)defrtrlist_update(dr, &rti->nd_rti_router_list);
+               TAILQ_INSERT_HEAD(&nd_rti_list, rti, nd_rti_entry);
+       }
+       /* If rti doesn't exist and lifetime is 0, simply ignore */
+       nd6_rti_list_signal_done();
+       lck_mtx_unlock(nd6_mutex);
+}
+
+void
+nd6_rti_purge(struct nd_route_info *new_rti)
+{
+       VERIFY(new_rti != NULL);
+       LCK_MTX_ASSERT(nd6_mutex, LCK_MTX_ASSERT_OWNED);
+
+       struct nd_route_info *rti = NULL;
+       nd6_rti_list_wait(__func__);
+
+       if ((rti = nd6_rti_lookup(new_rti)) != NULL) {
+               struct nd_defrouter *dr = NULL;
+               struct nd_defrouter *ndr = NULL;
+
+               TAILQ_FOREACH_SAFE(dr, &rti->nd_rti_router_list, dr_entry, ndr) {
+                       TAILQ_REMOVE(&rti->nd_rti_router_list, dr, dr_entry);
+                       defrtrlist_del(dr, &rti->nd_rti_router_list);
+                       NDDR_REMREF(dr);
+               }
+               TAILQ_REMOVE(&nd_rti_list, rti, nd_rti_entry);
+               ndrti_free(rti);
+       }
+       nd6_rti_list_signal_done();
+}