Add equal-cost multipath routing policy

This adds an equal-cost multipath routing policy to Ouroboros, based
on Nick Aerts' code. When selected, flows will send packets over all
paths with equal cost (hop count). Path selection is round-robin. It
does not yet take into account flows that are down.

Signed-off-by: Dimitri Staessens <[email protected]>
Signed-off-by: Sander Vrijders <[email protected]>

1 files changed, 58 insertions, 0 deletions

diff --git a/src/ipcpd/unicast/pol/multipath_pff.h b/src/ipcpd/unicast/pol/multipath_pff.h
new file mode 100644
index 00000000..a8ee088f
--- /dev/null
+++ b/src/ipcpd/unicast/pol/multipath_pff.h
@@ -0,0 +1,58 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2020
+ *
+ * Policy for PFF supporting multipath routing
+ *
+ *    Dimitri Staessens <[email protected]>
+ *    Sander Vrijders   <[email protected]>
+ *    Nick Aerts        <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., http://www.fsf.org/about/contact/.
+ */
+
+#ifndef OUROBOROS_IPCPD_UNICAST_MULTIPATH_PFF_H
+#define OUROBOROS_IPCPD_UNICAST_MULTIPATH_PFF_H
+
+#include "pol-pff-ops.h"
+
+struct pff_i * multipath_pff_create(void);
+
+void multipath_pff_destroy(struct pff_i * pff_i);
+
+void           multipath_pff_lock(struct pff_i * pff_i);
+
+void           multipath_pff_unlock(struct pff_i * pff_i);
+
+int            multipath_pff_add(struct pff_i * pff_i,
+                                 uint64_t       addr,
+                                 int *          fds,
+                                 size_t         len);
+
+int            multipath_pff_update(struct pff_i * pff_i,
+                                    uint64_t       addr,
+                                    int *          fds,
+                                    size_t         len);
+
+int            multipath_pff_del(struct pff_i * pff_i,
+                                 uint64_t       addr);
+
+void multipath_pff_flush(struct pff_i * pff_i);
+
+/* Returns fd towards next hop */
+int            multipath_pff_nhop(struct pff_i * pff_i,
+                                  uint64_t       addr);
+
+struct pol_pff_ops multipath_pff_ops;
+
+#endif /* OUROBOROS_IPCPD_UNICAST_MULTIPATH_PFF_H */