ipcpd: normal: Add alternate hop PFF

This adds a PFF that returns an alternate hop as next hop in case the
hop that would have been returned is down.

3 files changed, 470 insertions, 7 deletions

diff --git a/src/ipcpd/normal/pol/alternate_pff.c b/src/ipcpd/normal/pol/alternate_pff.c
new file mode 100644
index 00000000..3952bc82
--- /dev/null
+++ b/src/ipcpd/normal/pol/alternate_pff.c
@@ -0,0 +1,402 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2017
+ *
+ * Policy for PFF with alternate next hops
+ *
+ *    Dimitri Staessens <dimitri.staessens@ugent.be>
+ *    Sander Vrijders   <sander.vrijders@ugent.be>
+ *
+ * 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/.
+ */
+
+#define _POSIX_C_SOURCE 200112L
+
+#include "config.h"
+
+#include <ouroboros/hashtable.h>
+#include <ouroboros/errno.h>
+#include <ouroboros/list.h>
+
+#include <string.h>
+#include <assert.h>
+#include <pthread.h>
+
+#include "alternate_pff.h"
+
+struct nhop {
+        struct list_head next;
+        int              fd;
+};
+
+struct addr {
+        struct list_head next;
+        uint64_t         addr;
+};
+
+struct pff_i {
+        struct htable *  table;
+
+        struct list_head addrs;
+
+        struct list_head nhops_down;
+
+        pthread_rwlock_t lock;
+};
+
+struct pol_pff_ops alternate_pff_ops = {
+        .create            = alternate_pff_create,
+        .destroy           = alternate_pff_destroy,
+        .lock              = alternate_pff_lock,
+        .unlock            = alternate_pff_unlock,
+        .add               = alternate_pff_add,
+        .update            = alternate_pff_update,
+        .del               = alternate_pff_del,
+        .flush             = alternate_pff_flush,
+        .nhop              = alternate_pff_nhop,
+        .flow_state_change = alternate_flow_state_change
+};
+
+static int add_addr(struct pff_i * pff_i,
+                    uint64_t       addr)
+{
+        struct addr * a;
+
+        a = malloc(sizeof(*a));
+        if (a == NULL)
+                return -1;
+
+        a->addr = addr;
+
+        list_add(&a->next, &(pff_i->addrs));
+
+        return 0;
+}
+
+static void del_addr(struct pff_i * pff_i,
+                     uint64_t       addr)
+{
+        struct list_head * pos = NULL;
+        struct list_head * n   = NULL;
+
+        list_for_each_safe(pos, n, &(pff_i->addrs)) {
+                struct addr * e = list_entry(pos, struct addr, next);
+                if (e->addr == addr) {
+                        list_del(&e->next);
+                        free(e);
+                        return;
+                }
+        }
+}
+
+static void del_addrs(struct pff_i * pff_i)
+{
+        struct list_head * pos = NULL;
+        struct list_head * n   = NULL;
+
+        list_for_each_safe(pos, n, &(pff_i->addrs)) {
+                struct addr * e = list_entry(pos, struct addr, next);
+                list_del(&e->next);
+                free(e);
+        }
+}
+
+static void del_nhops_down(struct pff_i * pff_i)
+{
+        struct list_head * pos = NULL;
+        struct list_head * n   = NULL;
+
+        list_for_each_safe(pos, n, &(pff_i->nhops_down)) {
+                struct nhop * e = list_entry(pos, struct nhop, next);
+                list_del(&e->next);
+                free(e);
+        }
+}
+
+static int del_nhop_down(struct pff_i * pff_i,
+                         int            fd)
+{
+        struct list_head * pos = NULL;
+        struct list_head * n   = NULL;
+
+        list_for_each_safe(pos, n, &(pff_i->nhops_down)) {
+                struct nhop * e = list_entry(pos, struct nhop, next);
+                if (e->fd == fd) {
+                        list_del(&e->next);
+                        free(e);
+                        return 0;
+                }
+        }
+
+        return -1;
+}
+
+static int add_nhop_down(struct pff_i * pff_i,
+                         int            fd)
+{
+        struct nhop *      nhop;
+
+        nhop = malloc(sizeof(*nhop));
+        if (nhop == NULL)
+                return -1;
+
+        nhop->fd = fd;
+
+        list_add(&nhop->next, &(pff_i->nhops_down));
+
+        return 0;
+}
+
+static bool nhops_down_has(struct pff_i * pff_i,
+                           int            fd)
+{
+        struct list_head * pos = NULL;
+
+        list_for_each(pos, &pff_i->nhops_down) {
+                struct nhop * e = list_entry(pos, struct nhop, next);
+                if (e->fd == fd)
+                        return true;
+        }
+
+        return false;
+}
+
+static int add_to_htable(struct pff_i * pff_i,
+                         uint64_t       addr,
+                         int *          fd,
+                         size_t         len)
+{
+        int * val;
+
+        assert(pff_i);
+        assert(len > 0);
+
+        val = malloc(sizeof(*val) * (len + 1));
+        if (val == NULL)
+                goto fail_malloc;
+
+        memcpy(val, fd, len * sizeof(*val));
+        /* Put primary hop again at the end */
+        val[len] = val[0];
+
+        if (htable_insert(pff_i->table, addr, val, len))
+                goto fail_insert;
+
+        return 0;
+
+ fail_insert:
+        free(val);
+ fail_malloc:
+        return -1;
+}
+
+struct pff_i * alternate_pff_create(void)
+{
+        struct pff_i * tmp;
+
+        tmp = malloc(sizeof(*tmp));
+        if (tmp == NULL)
+                goto fail_malloc;
+
+        if (pthread_rwlock_init(&tmp->lock, NULL))
+                goto fail_lock;
+
+        tmp->table = htable_create(PFT_SIZE, false);
+        if (tmp->table == NULL)
+                goto fail_table;
+
+        list_head_init(&tmp->nhops_down);
+        list_head_init(&tmp->addrs);
+
+        return tmp;
+
+ fail_table:
+        pthread_rwlock_destroy(&tmp->lock);
+ fail_lock:
+        free(tmp);
+ fail_malloc:
+        return NULL;
+}
+
+void alternate_pff_destroy(struct pff_i * pff_i)
+{
+        assert(pff_i);
+
+        htable_destroy(pff_i->table);
+        del_nhops_down(pff_i);
+        pthread_rwlock_destroy(&pff_i->lock);
+        free(pff_i);
+}
+
+void alternate_pff_lock(struct pff_i * pff_i)
+{
+        pthread_rwlock_wrlock(&pff_i->lock);
+}
+
+void alternate_pff_unlock(struct pff_i * pff_i)
+{
+        pthread_rwlock_unlock(&pff_i->lock);
+}
+
+int alternate_pff_add(struct pff_i * pff_i,
+                      uint64_t       addr,
+                      int *          fd,
+                      size_t         len)
+{
+        assert(pff_i);
+        assert(len > 0);
+
+        if (add_to_htable(pff_i, addr, fd, len))
+                return -1;
+
+        if (add_addr(pff_i, addr)) {
+                htable_delete(pff_i->table, addr);
+                return -1;
+        }
+
+        return 0;
+}
+
+int alternate_pff_update(struct pff_i * pff_i,
+                         uint64_t       addr,
+                         int *          fd,
+                         size_t         len)
+{
+        assert(pff_i);
+        assert(len > 0);
+
+        if (htable_delete(pff_i->table, addr))
+                return -1;
+
+        if (add_to_htable(pff_i, addr, fd, len))
+                return -1;
+
+        return 0;
+}
+
+int alternate_pff_del(struct pff_i * pff_i,
+                      uint64_t       addr)
+{
+        assert(pff_i);
+
+        del_addr(pff_i, addr);
+
+        if (htable_delete(pff_i->table, addr))
+                return -1;
+
+        return 0;
+}
+
+void alternate_pff_flush(struct pff_i * pff_i)
+{
+        assert(pff_i);
+
+        htable_flush(pff_i->table);
+
+        del_nhops_down(pff_i);
+
+        del_addrs(pff_i);
+}
+
+int alternate_pff_nhop(struct pff_i * pff_i,
+                       uint64_t       addr)
+{
+        int    fd = -1;
+        size_t len;
+        void * el;
+
+        assert(pff_i);
+
+        pthread_rwlock_rdlock(&pff_i->lock);
+
+        if (htable_lookup(pff_i->table, addr, &el, &len)) {
+                pthread_rwlock_unlock(&pff_i->lock);
+                return -1;
+        }
+
+        fd = *((int *) el);
+
+        pthread_rwlock_unlock(&pff_i->lock);
+
+        return fd;
+}
+
+int alternate_flow_state_change(struct pff_i * pff_i,
+                                int            fd,
+                                bool           up)
+{
+        struct list_head * pos = NULL;
+        size_t             len;
+        void *             el;
+        int *              fds;
+        size_t             i;
+        int                tmp;
+
+        assert(pff_i);
+
+        pthread_rwlock_wrlock(&pff_i->lock);
+
+        if (up) {
+                if (del_nhop_down(pff_i, fd)) {
+                        pthread_rwlock_unlock(&pff_i->lock);
+                        return -1;
+                }
+        } else {
+                if (add_nhop_down(pff_i, fd)) {
+                        pthread_rwlock_unlock(&pff_i->lock);
+                        return -1;
+                }
+        }
+
+        list_for_each(pos, &pff_i->addrs) {
+                struct addr * e = list_entry(pos, struct addr, next);
+                if (htable_lookup(pff_i->table, e->addr, &el, &len)) {
+                        pthread_rwlock_unlock(&pff_i->lock);
+                        return -1;
+                }
+
+                fds = (int *) el;
+
+                if (up) {
+                        /* It is using an alternate */
+                        if (fds[len] == fd && fds[0] != fd) {
+                                for (i = 0 ; i < len; i++) {
+                                        /* Found the primary */
+                                        if (fds[i] == fd) {
+                                                tmp = fds[0];
+                                                fds[0] = fds[i];
+                                                fds[i] = tmp;
+                                                break;
+                                        }
+                                }
+                        }
+                } else {
+                        /* Need to switch to a (different) alternate */
+                        if (fds[0] == fd) {
+                                for (i = 0 ; i < len; i++) {
+                                        /* Usable alternate */
+                                        if (!nhops_down_has(pff_i, fds[i])) {
+                                                tmp = fds[0];
+                                                fds[0] = fds[i];
+                                                fds[i] = tmp;
+                                                break;
+                                        }
+                                }
+                        }
+                }
+        }
+
+        pthread_rwlock_unlock(&pff_i->lock);
+
+        return 0;
+}
diff --git a/src/ipcpd/normal/pol/alternate_pff.h b/src/ipcpd/normal/pol/alternate_pff.h
new file mode 100644
index 00000000..8fa2d514
--- /dev/null
+++ b/src/ipcpd/normal/pol/alternate_pff.h
@@ -0,0 +1,61 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2017
+ *
+ * Policy for PFF with alternate next hops
+ *
+ *    Dimitri Staessens <dimitri.staessens@ugent.be>
+ *    Sander Vrijders   <sander.vrijders@ugent.be>
+ *
+ * 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_NORMAL_ALTERNATE_PFF_H
+#define OUROBOROS_IPCPD_NORMAL_ALTERNATE_PFF_H
+
+#include "pol-pff-ops.h"
+
+struct pff_i * alternate_pff_create(void);
+
+void           alternate_pff_destroy(struct pff_i * pff_i);
+
+void           alternate_pff_lock(struct pff_i * pff_i);
+
+void           alternate_pff_unlock(struct pff_i * pff_i);
+
+int            alternate_pff_add(struct pff_i * pff_i,
+                                 uint64_t       addr,
+                                 int *          fd,
+                                 size_t         len);
+
+int            alternate_pff_update(struct pff_i * pff_i,
+                                    uint64_t       addr,
+                                    int *          fd,
+                                    size_t         len);
+
+int            alternate_pff_del(struct pff_i * pff_i,
+                                 uint64_t       addr);
+
+void           alternate_pff_flush(struct pff_i * pff_i);
+
+/* Returns fd towards next hop */
+int            alternate_pff_nhop(struct pff_i * pff_i,
+                                  uint64_t       addr);
+
+int            alternate_flow_state_change(struct pff_i * pff_i,
+                                           int            fd,
+                                           bool           up);
+
+struct pol_pff_ops alternate_pff_ops;
+
+#endif /* OUROBOROS_IPCPD_NORMAL_ALTERNATE_PFF_H */
diff --git a/src/ipcpd/normal/pol/simple_pff.c b/src/ipcpd/normal/pol/simple_pff.c
index 28f7aa2e..7af4663c 100644
--- a/src/ipcpd/normal/pol/simple_pff.c
+++ b/src/ipcpd/normal/pol/simple_pff.c
@@ -109,7 +109,7 @@ int simple_pff_add(struct pff_i * pff_i,
 
         *val = fd[0];
 
-        if (htable_insert(pff_i->table, addr, val)) {
+        if (htable_insert(pff_i->table, addr, val, 1)) {
                 free(val);
                 return -1;
         }
@@ -137,7 +137,7 @@ int simple_pff_update(struct pff_i * pff_i,
                 return -1;
         }
 
-        if (htable_insert(pff_i->table, addr, val)) {
+        if (htable_insert(pff_i->table, addr, val, 1)) {
                 free(val);
                 return -1;
         }
@@ -166,16 +166,16 @@ void simple_pff_flush(struct pff_i * pff_i)
 int simple_pff_nhop(struct pff_i * pff_i,
                     uint64_t       addr)
 {
-        int * j;
-        int   fd = -1;
+        void * j;
+        size_t len;
+        int    fd = -1;
 
         assert(pff_i);
 
         pthread_rwlock_rdlock(&pff_i->lock);
 
-        j = (int *) htable_lookup(pff_i->table, addr);
-        if (j != NULL)
-                fd = *j;
+        if (!htable_lookup(pff_i->table, addr, &j, &len))
+                fd = *((int *) j);
 
         pthread_rwlock_unlock(&pff_i->lock);