[HICN-369] Implement reconciliation state machine in face manager incl. reattempts in case of errors

Change-Id: Ia4ecf621fbd513d9e29313d2aaa487aa65811183
Signed-off-by: Jordan Augé <jordan.auge@cisco.com>

1 files changed, 551 insertions, 264 deletions

diff --git a/ctrl/facemgr/src/api.c b/ctrl/facemgr/src/api.c
index a1507bd70..19f211dbf 100644
--- a/ctrl/facemgr/src/api.c
+++ b/ctrl/facemgr/src/api.c
@@ -39,8 +39,8 @@
 #endif /* __ANDROID__ */
 
 #include <hicn/ctrl/face.h>
+#include <hicn/facemgr/facelet.h>
 #include "common.h"
-#include "facelet.h"
 #include "interface.h"
 #include "util/map.h"
 #include "util/set.h"
@@ -49,6 +49,7 @@
 
 #define DEFAULT_PORT 9695
 
+#define DEFAULT_REATTEMPT_DELAY_MS 250
 #define MAX_FDS 10
 
 typedef struct {
@@ -149,6 +150,7 @@ struct facemgr_s {
 #ifdef WITH_EXAMPLE_UPDOWN
     interface_t * updown;
 #endif
+    int timer_fd; /* Timer used for reattempts */
 };
 
 int
@@ -174,6 +176,8 @@ facemgr_initialize(facemgr_t * facemgr)
     if (!facemgr->cfg)
         goto ERR_CFG;
 
+    facemgr->timer_fd = 0;
+
     return 0;
 
 ERR_CFG:
@@ -194,6 +198,16 @@ facemgr_finalize(facemgr_t * facemgr)
     int ret = 0;
     int rc;
 
+    if (facemgr->timer_fd) {
+        rc = facemgr->callback(facemgr->callback_owner,
+                FACEMGR_CB_TYPE_UNREGISTER_TIMER, &facemgr->timer_fd);
+        if (rc < 0) {
+            ERROR("[facemgr_finalize] Error unregistering timer");
+            ret = -1;
+        }
+        facemgr->timer_fd = 0;
+    }
+
     rc = interface_map_finalize(&facemgr->interface_map);
     if (rc < 0) {
         ERROR("[facemgr_finalize] Could not finalize interface_map");
@@ -226,6 +240,8 @@ facemgr_finalize(facemgr_t * facemgr)
         ret = -1;
 #endif /* __linux__ */
 
+    interface_unregister_all();
+
     return ret;
 }
 
@@ -265,12 +281,49 @@ facemgr_create_with_config(facemgr_cfg_t * cfg)
     return facemgr;
 }
 
+/*
+ * \brief Heuristics to determine face type based on name, until a better
+ * solution is found
+ */
+netdevice_type_t
+facemgr_get_netdevice_type(const facemgr_t * facemgr, const char * interface_name)
+{
+    if (strncmp(interface_name, "lo", 2) == 0) {
+        return NETDEVICE_TYPE_LOOPBACK;
+    }
+    if ((strncmp(interface_name, "eth", 3) == 0) ||
+            (strncmp(interface_name, "en", 2) == 0)) {
+        /* eth* en* enx* */
+        return NETDEVICE_TYPE_WIRED;
+    }
+    if (strncmp(interface_name, "wl", 2) == 0) {
+        /* wlan* wlp* wlx* */
+        return NETDEVICE_TYPE_WIFI;
+    }
+    if (strncmp(interface_name, "rmnet_ipa", 9) == 0) {
+        /* Qualcomm IPA driver */
+        return NETDEVICE_TYPE_UNDEFINED;
+    }
+    if ((strncmp(interface_name, "rmnet", 5) == 0) ||
+            (strncmp(interface_name, "rev_rmnet", 9) == 0) ||
+            (strncmp(interface_name, "ccmni", 5) == 0)) {
+        /*
+         * rmnet* (Qualcomm) ccmni* (MediaTek)
+         */
+        return NETDEVICE_TYPE_CELLULAR;
+    }
+    /* usb0 might be cellular (eg Zenfone2) */
+    /* what about tethering */
+    /* tun* dummy* ... */
+    /* bnet* pan* hci* for bluetooth */
+    return NETDEVICE_TYPE_UNDEFINED;
+}
+
 int facemgr_callback(facemgr_t * facemgr, interface_cb_type_t type, void * data);
 
 int
 facemgr_create_interface(facemgr_t * facemgr, const char * name, const char * type, void * cfg, interface_t ** pinterface)
 {
-    int fd;
     char rand_name[RAND_NAME_LEN+1];
     interface_t * interface;
 
@@ -291,10 +344,6 @@ facemgr_create_interface(facemgr_t * facemgr, const char * name, const char * ty
     }
     interface_set_callback(interface, facemgr, facemgr_callback);
 
-    fd = interface_initialize(interface, cfg);
-    if (fd < 0)
-        goto ERR_INIT;
-
     interface_map_data_t * interface_map_data = malloc(sizeof(interface_map_data_t));
     if (!interface_map_data)
         goto ERR_MAP_DATA;
@@ -308,6 +357,15 @@ facemgr_create_interface(facemgr_t * facemgr, const char * name, const char * ty
     if (interface_map_add(&facemgr->interface_map, interface->name, interface_map_data) < 0)
         goto ERR_MAP_ADD;
 
+    /*
+     * This should be called _after_ the interface_map is initialized otherwise
+     * it will be impossible to register fds from *_initialize
+     */
+    if (interface_initialize(interface, cfg) < 0) {
+        ERROR("[facemgr_create_interface] Error initializing interface");
+        goto ERR_INIT;
+    }
+
     DEBUG("Interface %s created successfully.", name);
     if (pinterface)
         *pinterface = interface;
@@ -342,7 +400,13 @@ facemgr_delete_interface(facemgr_t * facemgr, interface_t * interface)
 
     for (unsigned i = 0; i < interface_map_data->num_fds; i++) {
         int fd = interface_map_data->fds[i];
-        facemgr->callback(facemgr->callback_owner, FACEMGR_CB_TYPE_UNREGISTER_FD, &fd);
+        fd_callback_data_t fd_callback_data = {
+            .fd = fd,
+            .owner = facemgr,
+            .callback = NULL,
+            .data = NULL,
+        };
+        facemgr->callback(facemgr->callback_owner, FACEMGR_CB_TYPE_UNREGISTER_FD, &fd_callback_data);
         if (rc < 0)
             WARN("[facemgr_delete_interface] Error unregistering fd %d for interface", fd);
     }
@@ -494,7 +558,7 @@ facemgr_facelet_satisfy_rules(facemgr_t * facemgr, facelet_t * facelet)
     }
 
     netdevice_type_t netdevice_type = NETDEVICE_TYPE_UNDEFINED;
-#ifdef __ANDROID__
+//#ifdef __ANDROID__
     /*
      * In addition to netdevice, netdevice_type should be present to correctly
      * apply rules
@@ -504,7 +568,7 @@ facemgr_facelet_satisfy_rules(facemgr_t * facemgr, facelet_t * facelet)
         ERROR("[facemgr_facelet_satisfy_rules] Error retrieving netdevice_type from facelet");
         return -2;
     }
-#endif /* __ANDROID__ */
+//#endif /* __ANDROID__ */
 
     /* Ignore */
     bool ignore;
@@ -578,11 +642,13 @@ facemgr_complement_facelet_au(facemgr_t * facemgr, facelet_t * facelet)
     }
 
     DEBUG("Querying android utility...");
-    facelet_set_au_done(facelet);
 
     /* /!\ Synchronous code here /!\ */
-    if (facemgr_query_android_utility(facemgr, netdevice) < 0)
+    if (facemgr_query_android_utility(facemgr, netdevice) < 0) {
         return -1;
+    }
+
+    facelet_set_au_done(facelet);
     return 0;
 }
 #endif /* __ANDROID__ */
@@ -607,7 +673,7 @@ facemgr_complement_facelet_bj(facemgr_t * facemgr, facelet_t * facelet)
     }
 
     netdevice_type_t netdevice_type = NETDEVICE_TYPE_UNDEFINED;
-#ifdef __ANDROID__
+//#ifdef __ANDROID__
     /*
      * In addition to netdevice, netdevice_type should be present to correctly
      * apply rules
@@ -617,7 +683,7 @@ facemgr_complement_facelet_bj(facemgr_t * facemgr, facelet_t * facelet)
         ERROR("[facemgr_complement_facelet_bj] Error retrieving netdevice_type from facelet");
         return -2;
     }
-#endif /* __ANDROID__ */
+//#endif /* __ANDROID__ */
 
     bool discovery;
     if (facemgr_cfg_get_discovery(facemgr->cfg, &netdevice, netdevice_type,
@@ -679,7 +745,7 @@ facemgr_complement_facelet_manual(facemgr_t * facemgr, facelet_t * facelet)
     }
 
     netdevice_type_t netdevice_type = NETDEVICE_TYPE_UNDEFINED;
-#ifdef __ANDROID__
+//#ifdef __ANDROID__
     /*
      * In addition to netdevice, netdevice_type should be present to correctly
      * apply rules
@@ -689,7 +755,7 @@ facemgr_complement_facelet_manual(facemgr_t * facemgr, facelet_t * facelet)
         ERROR("[facemgr_complement_facelet_manual] Error retrieving netdevice_type from facelet");
         return -2;
     }
-#endif /* __ANDROID__ */
+//#endif /* __ANDROID__ */
 
     int family = AF_UNSPEC;
     if (facelet_has_family(facelet)) {
@@ -798,11 +864,22 @@ facemgr_complement_facelet(facemgr_t * facemgr, facelet_t * facelet)
     if (!facelet_has_key(facelet))
         return -2;
 
+#if 0
 #ifdef __ANDROID__
     rc = facemgr_complement_facelet_au(facemgr, facelet);
     if (rc != -2)
         return rc;
 #endif /* __ANDROID__ */
+#endif
+    if (!facelet_has_netdevice_type(facelet)) {
+        netdevice_t netdevice = NETDEVICE_EMPTY;
+        rc = facelet_get_netdevice(facelet, &netdevice);
+        if (rc < 0) {
+            ERROR("[facemgr_complement_facelet] Error retrieving netdevice from facelet");
+            return -1;
+        }
+        facelet_set_netdevice_type(facelet, facemgr_get_netdevice_type(facemgr, netdevice.name));
+    }
 
     /* We continue only if the current call was not applicable. In the current
      * setting we have no interface that can be requested in parallel, and no
@@ -825,105 +902,279 @@ facemgr_complement_facelet(facemgr_t * facemgr, facelet_t * facelet)
     return 0;
 }
 
-/**
- * \brief Process facelet CREATE event
- * \param [in] facemgr - Pointer to the face manager instance
- * \param [in] facelet - Pointer to the facelet event to process
- * \return 0 if everything went correctly, or -1 in case of error.
- */
-int
-facemgr_process_create(facemgr_t * facemgr, facelet_t * facelet)
+int facemgr_assign_face_type(facemgr_t * facemgr, facelet_t * facelet)
 {
-    /*
-     * We create an interface locally, which does not means it should not exist
-     * remotely. Once such codepath is enabled, the two facelets will have been
-     * merged and we need to handle an eventual update on our side.
-     *
-     * In the same way, we need to check for the equivalence of face types etc.
-     */
-    int rc;
+    /* As key, netdevice and family should always be present */
+    netdevice_t netdevice = NETDEVICE_EMPTY;
+    int rc = facelet_get_netdevice(facelet, &netdevice);
+    if (rc < 0) {
+        ERROR("[facemgr_facelet_satisfy_rules] Error retrieving netdevice from facelet");
+        return -1;
+    }
 
+    netdevice_type_t netdevice_type = NETDEVICE_TYPE_UNDEFINED;
+//#ifdef __ANDROID__
     /*
-     * If the facelet does not satisfy filters, we do not lose any information
-     * but do not take any action to complement the face
+     * In addition to netdevice, netdevice_type should be present to correctly
+     * apply rules
      */
-    rc = facemgr_facelet_satisfy_rules(facemgr, facelet);
-    if (rc == -3) {
-        facelet_set_status(facelet, FACELET_STATUS_IGNORED);
-        /* Does not satisfy rules */
-        return 0;
+    rc = facelet_get_netdevice_type(facelet, &netdevice_type);
+    if (rc < 0) {
+        ERROR("[facemgr_facelet_satisfy_rules] Error retrieving netdevice_type from facelet");
+        return -2;
     }
+//#endif /* __ANDROID__ */
 
-    // FIXME: we should complement a part of the facelet, so that we don't
-    // necessarily keep this information if we get more locally. Or at least we
-    // should remember that.
-    if (rc == -2) {
-        /*
-         * We don't have equivalent for linux right now, heuristic is only used
-         * at the end... might change.
-         */
-#ifdef __ANDROID__
-        /* Priority is given to information that complements a face */
-        if (facemgr_complement_facelet_au(facemgr, facelet) < 0) {
-            ERROR("[facemgr_process_create] Error while attempting to complement face for fields required by rule application");
-            return -1;
-        }
-        return 0;
-#endif /* __ANDROID__ */
+    facemgr_face_type_t face_type = FACEMGR_FACE_TYPE_UNDEFINED;
+    if (facemgr_cfg_get_face_type(facemgr->cfg, &netdevice, netdevice_type, &face_type) < 0)
+        return rc;
+    facelet_set_face_type(facelet, face_type);
+    return 0;
+}
+
+/*
+ * This function performs one step of the state machine associated to the
+ * facelet, from initial creation, to synchronization with the forwarder.
+ *
+ * We assume the facelet is already present in the cache
+ */
+int
+facemgr_process_facelet(facemgr_t * facemgr, facelet_t * facelet)
+{
+    int rc;
+
+    switch(facelet_get_status(facelet)) {
+        case FACELET_STATUS_UNCERTAIN:
+            /*
+             * All new faces are marked UNCERTAIN. We need to check whether we
+             * have sufficient information to check rules, if not proceed,
+             * otherwise possibly mark the face as IGNORED. Otherwise, we verify
+             * the completeness of the information we have, and continue towards
+             * being able to mark the face as CREATE.
+             */
+            rc = facemgr_facelet_satisfy_rules(facemgr, facelet);
+            switch(rc) {
+                case -3:
+                    /* Does not satisfy rules */
+                    facelet_set_status(facelet, FACELET_STATUS_IGNORED);
+                    return 0;
+
+                case -2:
+                    /* Not enough information: AU in fact */
+                    if (facemgr_complement_facelet(facemgr, facelet) < 0) {
+                        ERROR("[facemgr_process_facelet] Error while attempting to complement face for fields required by face creation");
+                        goto ERR;
+                    }
+                    return 0;
+
+                case 0:
+                    /* Ok pass rules */
+                    break;
+
+                default:
+                    /* -1 - Error */
+                    goto ERR;
+            }
+
+            if (facemgr_assign_face_type(facemgr, facelet) < 0) {
+                ERROR("[facemgr_process_facelet] Could not assign face type");
+                goto ERR;
+            }
+            facelet_set_status(facelet, FACELET_STATUS_INCOMPLETE);
+            /* Continue in case facelet satisfies rules */
+
+        case FACELET_STATUS_INCOMPLETE:
+            if (!facelet_validate_face(facelet)) {
+                /* We need additional information */
+                if (facemgr_complement_facelet(facemgr, facelet) < 0) {
+                    ERROR("[facemgr_process_facelet] Error while attempting to complement face for fields required by face creation");
+                    goto ERR;
+                }
+            }
+            if (!facelet_validate_face(facelet))
+                return 0;
+
+            facelet_set_status(facelet, FACELET_STATUS_CREATE);
+            /* Continue in case we need to proceed to creation */
+
+        case FACELET_STATUS_CREATE:
+            facelet_set_event(facelet, FACELET_EVENT_CREATE);
+            if (interface_on_event(facemgr->hl, facelet) < 0) {
+                ERROR("[facemgr_process_facelet] Failed to create face");
+                goto ERR;
+            }
+
+            /* This works assuming the call to hicn-light is blocking */
+            facelet_set_status(facelet, FACELET_STATUS_CLEAN);
+            break;
+
+
+        case FACELET_STATUS_UPDATE:
+            facelet_set_event(facelet, FACELET_EVENT_UPDATE);
+            if (interface_on_event(facemgr->hl, facelet) < 0) {
+                ERROR("[facemgr_process_facelet] Failed to update face");
+                goto ERR;
+            }
+
+            /* This works assuming the call to hicn-light is blocking */
+            facelet_set_status(facelet, FACELET_STATUS_CLEAN);
+            break;
+
+        case FACELET_STATUS_DELETE:
+            facelet_set_event(facelet, FACELET_EVENT_DELETE);
+            if (interface_on_event(facemgr->hl, facelet) < 0) {
+                ERROR("[facemgr_process_facelet] Failed to delete face");
+                goto ERR;
+            }
+
+            /* This works assuming the call to hicn-light is blocking */
+            DEBUG("[facemgr_process_facelet] Cleaning cached data");
+            facelet_unset_local_addr(facelet);
+            facelet_unset_local_port(facelet);
+            facelet_unset_remote_addr(facelet);
+            facelet_unset_remote_port(facelet);
+            facelet_unset_bj_done(facelet);
+            //facelet_unset_au_done(facelet);
+
+            facelet_set_status(facelet, FACELET_STATUS_DELETED);
+            break;
+
+        case FACELET_STATUS_CLEAN:
+        case FACELET_STATUS_IGNORED:
+        case FACELET_STATUS_DELETED:
+            /* Nothing to do */
+            break;
+
+        case FACELET_STATUS_UNDEFINED:
+        case FACELET_STATUS_N:
+            ERROR("[facemgr_process_facelet] Unexpected facelet status");
+            goto ERR;
     }
-    if (rc < 0)
-        return -1;
 
-//    netdevice_t netdevice = NETDEVICE_EMPTY;
-//    if (facelet_get_netdevice(facelet, &netdevice) < 0) {
-//        ERROR("[facemgr_process_create] Error retrieving netdevice from facelet");
-//        return -1;
-//    }
-//
-//    netdevice_type_t netdevice_type = NETDEVICE_TYPE_UNDEFINED;
-//#ifdef __ANDROID__
-//    /*
-//     * In addition to netdevice, netdevice_type should be present to correctly
-//     * apply rules
-//     */
-//    if (facelet_get_netdevice_type(facelet, &netdevice_type) < 0) {
-//        ERROR("[facemgr_process_create] Error retrieving netdevice_type from facelet");
-//        return -2;
-//    }
-//#endif /* __ANDROID__ */
+    facelet_set_status_error(facelet, false);
+    return 0;
 
+ERR:
+    facelet_set_status_error(facelet, true);
+    return -1;
+}
 
-    char facelet_s[MAXSZ_FACELET];
-    facelet_snprintf(facelet_s, MAXSZ_FACELET, facelet);
-    //DEBUG("---[ FACELET CREATE : %s ] ---", facelet_s);
+int
+facemgr_reattempt_timeout(facemgr_t * facemgr, int fd, void * data)
+{
+    bool has_error = false;
 
-    /* Do we have enough information about the facelet ? */
-    if (!facelet_validate_face(facelet)) {
-        if (facemgr_complement_facelet(facemgr, facelet) < 0) {
-            ERROR("[facemgr_process_create] Error while attempting to complement face for fields required by face creation");
-            return -1;
+    assert(data == NULL);
+
+    /* Free all facelets from cache */
+    facelet_t ** facelet_array;
+    int n = facelet_cache_get_array(&facemgr->facelet_cache, &facelet_array);
+    if (n < 0) {
+        ERROR("[facemgr_reattempt_timeout] Could not retrieve facelets in cache");
+    } else {
+        for (unsigned i = 0; i < n; i++) {
+            facelet_t * facelet = facelet_array[i];
+
+            if (!facelet_get_status_error(facelet))
+                continue;
+
+            char buf[MAXSZ_FACELET];
+            facelet_snprintf(buf, MAXSZ_FACELET, facelet);
+            DEBUG("Reattempt to process failed facelet %s", buf);
+            if (facemgr_process_facelet(facemgr, facelet) < 0) {
+                ERROR("[facemgr_reattempt_timeout] Error processing facelet");
+                has_error = true;
+                continue;
+            }
+            facelet_set_status_error(facelet, false);
         }
-        // we should not stop after complement_manual but create a face if
-        // possible... so we add a second validation
+        free(facelet_array);
     }
 
-    if (!facelet_validate_face(facelet))
+    if (has_error)
         return 0;
 
-    /*
-     * Is the forwarder connected, and has the facelet cache already sync'ed the
-     * remote faces ?
-     */
-    // TODO
+    DEBUG("Cancelling timer");
+    if (facemgr->callback(facemgr->callback_owner,
+            FACEMGR_CB_TYPE_UNREGISTER_TIMER, &facemgr->timer_fd) < 0) {
+        ERROR("[facemgr_reattempt_timeout] Error unregistering reattempt timer");
+        return -1;
+    }
+    facemgr->timer_fd = 0;
+    return 0;
+}
 
-    /*
-     * Actually create the face on the forwarder
-     *
-     * FIXME Currently hicn-light is hardcoded
-     */
-    if (interface_on_event(facemgr->hl, facelet) < 0)
+int
+facemgr_start_reattempts(facemgr_t * facemgr)
+{
+    if (facemgr->timer_fd > 0)
+        return 0;
+
+    timer_callback_data_t timer_callback = {
+        .delay_ms = DEFAULT_REATTEMPT_DELAY_MS,
+        .owner = facemgr,
+        .callback = (fd_callback_t)facemgr_reattempt_timeout,
+        .data = NULL,
+    };
+    facemgr->timer_fd = facemgr->callback(facemgr->callback_owner,
+            FACEMGR_CB_TYPE_REGISTER_TIMER, &timer_callback);
+    return (facemgr->timer_fd > 0);
+}
+
+/**
+ * \brief Process facelet CREATE event
+ * \param [in] facemgr - Pointer to the face manager instance
+ * \param [in] facelet - Pointer to the facelet event to process
+ * \return 0 if everything went correctly, or -1 in case of error.
+ *         -2 means we ignored the face purposedly
+ */
+int
+facemgr_process_facelet_create(facemgr_t * facemgr, facelet_t * facelet)
+{
+    switch(facelet_get_status(facelet)) {
+        case FACELET_STATUS_UNCERTAIN:
+        case FACELET_STATUS_INCOMPLETE:
+        case FACELET_STATUS_CREATE:
+            /* No change */
+            break;
+        case FACELET_STATUS_UPDATE:
+        case FACELET_STATUS_DELETE:
+            /*
+             * Unlikely. The face had been created and is planned to
+             * be deleted. Schedule for creation (we should have all
+             * needed information), but make sure to handle errors
+             * correctly if the face is still present.
+             * TODO What if some fields have been updated ?
+             */
+            facelet_set_status(facelet, FACELET_STATUS_CREATE);
+            break;
+        case FACELET_STATUS_CLEAN:
+        case FACELET_STATUS_IGNORED:
+            /*
+             * We should have nothing to do unless some fields have
+             * been updated.
+             */
+            break;
+
+        case FACELET_STATUS_DELETED:
+            /*
+             * Unless rules have changed, we only need to recover
+             * missing information, and proceed to face creation.
+             * Rule changes should be handled separately.
+             */
+            facelet_set_status(facelet, FACELET_STATUS_INCOMPLETE);
+            break;
+        case FACELET_STATUS_UNDEFINED:
+        case FACELET_STATUS_N:
+            ERROR("[facemgr_process_facelet_create] Unexpected facelet status");
+            return -1;
+    }
+
+    if (facemgr_process_facelet(facemgr, facelet) < 0) {
+        ERROR("[facemgr_process_facelet_create] Error processing facelet");
         return -1;
-    facelet_set_status(facelet, FACELET_STATUS_CLEAN);
+    }
+
     return 0;
 }
 
@@ -935,15 +1186,15 @@ facemgr_process_create(facemgr_t * facemgr, facelet_t * facelet)
  *         -2 means we ignored the face purposedly
  */
 int
-facemgr_process_get(facemgr_t * facemgr, facelet_t * facelet)
+facemgr_process_facelet_get(facemgr_t * facemgr, facelet_t * facelet)
 {
-    facelet_set_status(facelet, FACELET_STATUS_CLEAN);
     if (facelet_has_netdevice(facelet)) {
         netdevice_t netdevice;
         if (facelet_get_netdevice(facelet, &netdevice) < 0)
             return -1;
         if (!IS_VALID_NETDEVICE(netdevice))
             return -2;
+        facelet_set_status(facelet, FACELET_STATUS_CLEAN);
         return facelet_cache_add(&facemgr->facelet_cache, facelet);
     }
     return -2;
@@ -954,146 +1205,38 @@ facemgr_process_get(facemgr_t * facemgr, facelet_t * facelet)
  * \param [in] facemgr - Pointer to the face manager instance
  * \param [in] facelet - Pointer to the facelet event to process
  * \return 0 if everything went correctly, or -1 in case of error.
+ *         -2 means we ignored the face purposedly
  */
 int
-facemgr_process_update(facemgr_t * facemgr, facelet_t * facelet)
+facemgr_process_facelet_update(facemgr_t * facemgr, facelet_t * facelet)
 {
-    /* This is the most complex operation since we have the same problems as in
-     * CREATE + the need to manage changes...
-     *
-     * This might eventually trigger a face deletion...
-     */
-
-    /*
-     * Update in local does not mean the face should not be created remotely as
-     * it might be the first time we have enough information to create it
-     */
-
-    char facelet_s[MAXSZ_FACELET];
-    facelet_snprintf(facelet_s, MAXSZ_FACELET, facelet);
-    //DEBUG("---[ FACELET UPDATE : %s ] ---", facelet_s);
-
-    /* Sets face type */
-    if (!facelet_has_face_type(facelet)) {
-
-        /* As key, netdevice and family should always be present */
-        netdevice_t netdevice = NETDEVICE_EMPTY;
-        int rc = facelet_get_netdevice(facelet, &netdevice);
-        if (rc < 0) {
-            ERROR("[facemgr_facelet_satisfy_rules] Error retrieving netdevice from facelet");
-            return -1;
-        }
-
-        netdevice_type_t netdevice_type = NETDEVICE_TYPE_UNDEFINED;
-#ifdef __ANDROID__
-        /*
-         * In addition to netdevice, netdevice_type should be present to correctly
-         * apply rules
-         */
-        rc = facelet_get_netdevice_type(facelet, &netdevice_type);
-        if (rc < 0) {
-            ERROR("[facemgr_facelet_satisfy_rules] Error retrieving netdevice_type from facelet");
-            return -2;
-        }
-#endif /* __ANDROID__ */
-
-        facemgr_face_type_t face_type = FACEMGR_FACE_TYPE_UNDEFINED;
-        if (facemgr_cfg_get_face_type(facemgr->cfg, &netdevice, netdevice_type, &face_type) < 0)
-            return rc;
-        facelet_set_face_type(facelet, face_type);
-    }
-
-    /* Process GET/UDPATE... */
-    int rc;
     switch(facelet_get_status(facelet)) {
-        case FACELET_STATUS_UNDEFINED:
-            ERROR("[facemgr_process_update] Unexpected facelet status");
-            return -1;
-
-        case FACELET_STATUS_DELETED:
-        case FACELET_STATUS_NEW:
-            /*
-             * If the remote action should be a CREATE, then we need to check
-             * whether we have enough information about the face...
-             */
-            if (!facelet_validate_face(facelet)) {
-                if (facemgr_complement_facelet(facemgr, facelet) < 0) {
-                    ERROR("[facemgr_process_update] Error while attempting to complement face for fields required by face creation");
-                    return -1;
-                }
-            }
-
-            rc = facemgr_facelet_satisfy_rules(facemgr, facelet);
-            if (rc == -3) {
-                facelet_set_status(facelet, FACELET_STATUS_IGNORED);
-                /* Does not satisfy rules */
-                return 0;
-            }
-
-            if (!facelet_validate_face(facelet))
-                return 0;
-
-            facelet_set_event(facelet, FACELET_EVENT_CREATE);
-            interface_on_event(facemgr->hl, facelet);
-
-            /* This works assuming the call to hicn-light is blocking */
-            facelet_set_status(facelet, FACELET_STATUS_CLEAN);
+        case FACELET_STATUS_UNCERTAIN:
+        case FACELET_STATUS_INCOMPLETE:
+        case FACELET_STATUS_CREATE:
+        case FACELET_STATUS_UPDATE:
+            /* No change */
             break;
-
         case FACELET_STATUS_CLEAN:
-            /* Nothing to do */
-            break;
-
-        case FACELET_STATUS_DIRTY:
-            /*
-             * For now we assume only local changes, and proceed to try and
-             * update the hICN forwarder.
-             *
-             * In case of update, the face exists which means we should already
-             * have enough information
-             */
-            if (!facelet_validate_face(facelet)) {
-                if (facemgr_complement_facelet(facemgr, facelet) < 0) {
-                    ERROR("[facemgr_process_create] Error while attempting to complement face for fields required by face creation");
-                    return -1;
-                }
-            }
-
-            rc = facemgr_facelet_satisfy_rules(facemgr, facelet);
-            if (rc == -3) {
-                facelet_set_status(facelet, FACELET_STATUS_IGNORED);
-                /* Does not satisfy rules */
-                return 0;
-            }
-
-            if (!facelet_validate_face(facelet))
-                return 0;
-
-            facelet_set_event(facelet, FACELET_EVENT_UPDATE);
-            if (interface_on_event(facemgr->hl, facelet) < 0)
-                return -1;
-
-            /* This works assuming the call to hicn-light is blocking and we
-             * have proceeded to all udpates */
-            facelet_set_status(facelet, FACELET_STATUS_CLEAN);
+            facelet_set_status(facelet, FACELET_STATUS_UPDATE);
             break;
-
-        case FACELET_STATUS_CONFLICT:
-            ERROR("[facemgr_process_update] Conflict resolution (not) yet implemented");
-            return -1;
-
-        case FACELET_STATUS_ERROR:
-            ERROR("[facemgr_process_update] Case ERROR (not) yet implemented");
-            break;
-
+        case FACELET_STATUS_DELETE:
+        case FACELET_STATUS_DELETED:
         case FACELET_STATUS_IGNORED:
-            ERROR("[facemgr_process_update] Case IGNORED (not) yet implemented");
+            /* Reconsider face creation in light of new information */
+            facelet_set_status(facelet, FACELET_STATUS_UNCERTAIN);
             break;
-
+        case FACELET_STATUS_UNDEFINED:
         case FACELET_STATUS_N:
-            ERROR("[facemgr_process_update] Facelet in error");
+            ERROR("[facemgr_process_facelet_update] Unexpected facelet status");
             return -1;
     }
+
+    if (facemgr_process_facelet(facemgr, facelet) < 0) {
+        ERROR("[facemgr_process_facelet_update] Error processing facelet");
+        return -1;
+    }
+
     return 0;
 }
 
@@ -1102,34 +1245,47 @@ facemgr_process_update(facemgr_t * facemgr, facelet_t * facelet)
  * \param [in] facemgr - Pointer to the face manager instance
  * \param [in] facelet - Pointer to the facelet event to process
  * \return 0 if everything went correctly, or -1 in case of error.
+ *         -2 means we ignored the face purposedly
  */
 int
-facemgr_process_delete(facemgr_t * facemgr, facelet_t * facelet)
+facemgr_process_facelet_delete(facemgr_t * facemgr, facelet_t * facelet)
 {
+    switch(facelet_get_status(facelet)) {
+        case FACELET_STATUS_UNCERTAIN:
+        case FACELET_STATUS_INCOMPLETE:
+        case FACELET_STATUS_CREATE:
+            facelet_unset_local_addr(facelet);
+            facelet_unset_local_port(facelet);
+            facelet_unset_remote_addr(facelet);
+            facelet_unset_remote_port(facelet);
+            facelet_unset_bj_done(facelet);
+            //facelet_unset_au_done(facelet);
+            facelet_set_status(facelet, FACELET_STATUS_DELETED);
+            break;
+        case FACELET_STATUS_UPDATE:
+        case FACELET_STATUS_CLEAN:
+            facelet_set_status(facelet, FACELET_STATUS_DELETE);
+            break;
+        case FACELET_STATUS_DELETE:
+        case FACELET_STATUS_IGNORED:
+        case FACELET_STATUS_DELETED:
+            /* Nothing to do */
+            DEBUG("%s\n", facelet_status_str[facelet_get_status(facelet)]);
+            break;
+        case FACELET_STATUS_UNDEFINED:
+        case FACELET_STATUS_N:
+            ERROR("[facemgr_process_facelet_delete] Unexpected facelet status");
+            return -1;
+    }
 
-    DEBUG("[facemgr_process_delete] Deleting facelet on hicn-light");
-    if (interface_on_event(facemgr->hl, facelet) < 0)
+    if (facemgr_process_facelet(facemgr, facelet) < 0) {
+        ERROR("[facemgr_process_facelet_delete] Error processing facelet");
         return -1;
-
-    /*
-     * It might be tempting to cache old information, but for now we reset the
-     * facelet state that might change (such as IP addresses etc).
-     * netdevice, netdevice_type and admin_state should not be affected.
-     */
-    DEBUG("[facemgr_process_delete] Cleaning cached data");
-    facelet_unset_local_addr(facelet);
-    facelet_unset_local_port(facelet);
-    facelet_unset_remote_addr(facelet);
-    facelet_unset_remote_port(facelet);
-
-    facelet_set_status(facelet, FACELET_STATUS_DELETED);
-
-    facelet_unset_bj_done(facelet);
+    }
 
     return 0;
 }
 
-
 /**
  * \brief Process incoming events from interfaces
  *
@@ -1147,37 +1303,41 @@ facemgr_on_event(facemgr_t * facemgr, facelet_t * facelet_in)
 
     char facelet_s[MAXSZ_FACELET];
     facelet_snprintf(facelet_s, MAXSZ_FACELET, facelet_in);
-    //DEBUG("----------------------------------");
     DEBUG("EVENT %s", facelet_s);
 
     facelet_t ** cached_facelets = NULL;
     int n = facelet_cache_lookup(&facemgr->facelet_cache, facelet_in, &cached_facelets);
     if (n < 0) {
         ERROR("[facemgr_on_event] Error during cache lookup");
-        goto ERR;
+        free(facelet_in);
+        return -1;
     }
     if (n == 0) {
         /* This is a new facelet...  we expect a CREATE event. */
         switch(facelet_get_event(facelet_in)) {
             case FACELET_EVENT_CREATE:
 
+                facelet_set_status(facelet_in, FACELET_STATUS_UNCERTAIN);
                 if (facelet_cache_add(&facemgr->facelet_cache, facelet_in) < 0) {
                     ERROR("[facemgr_on_event] Error adding facelet to cache");
+                    free(facelet_in);
+                    free(cached_facelets);
                     return -1;
                 }
-                //DEBUG("Facelet added to cache");
 
                 remove_facelet = false;
 
-                if (facemgr_process_create(facemgr, facelet_in) < 0) {
-                    ERROR("[facemgr_on_event] Error processing CREATE event");
+                if (facemgr_process_facelet_create(facemgr, facelet_in) < 0) {
+                    ERROR("[facemgr_on_event] Error processing facelet CREATE event");
+                    ret = -1;
                     goto ERR;
                 }
+
                 break;
 
             case FACELET_EVENT_GET:
                 /* Insert new facelet in cached */
-                rc = facemgr_process_get(facemgr, facelet_in);
+                rc = facemgr_process_facelet_get(facemgr, facelet_in);
                 if (rc == 0)
                     remove_facelet = false;
                 if (rc == -1) {
@@ -1227,10 +1387,12 @@ facemgr_on_event(facemgr_t * facemgr, facelet_t * facelet_in)
                     ERROR("[facemgr_on_event] Error merging facelets");
                     continue;
                 }
-                if (facemgr_process_create(facemgr, facelet) < 0) {
-                    ERROR("[facemgr_on_event] Error processing CREATE event");
+
+                if (facemgr_process_facelet_create(facemgr, facelet_in) < 0) {
+                    ERROR("[facemgr_on_event] Error processing facelet CREATE event");
                     ret = -1;
                 }
+
                 continue;
 
             case FACELET_EVENT_GET: /* should be an INFORM message */
@@ -1245,8 +1407,8 @@ facemgr_on_event(facemgr_t * facemgr, facelet_t * facelet_in)
                     ERROR("[facemgr_on_event] Error merging facelets");
                     continue;
                 }
-                if (facemgr_process_update(facemgr, facelet) < 0) {
-                    ERROR("[facemgr_on_event] Error processing UPDATE event");
+                if (facemgr_process_facelet_update(facemgr, facelet) < 0) {
+                    ERROR("[facemgr_on_event] Error processing facelet UPDATE event");
                     ret = -1;
                 }
                 continue;
@@ -1256,8 +1418,8 @@ facemgr_on_event(facemgr_t * facemgr, facelet_t * facelet_in)
                     ERROR("[facemgr_on_event] Error merging facelets");
                     continue;
                 }
-                if (facemgr_process_delete(facemgr, facelet) < 0) {
-                        ERROR("[facemgr_on_event] Error processing DELETE event");
+                if (facemgr_process_facelet_delete(facemgr, facelet) < 0) {
+                        ERROR("[facemgr_on_event] Error processing facelet DELETE event");
                     ret = -1;
                 }
                 continue;
@@ -1268,7 +1430,6 @@ facemgr_on_event(facemgr_t * facemgr, facelet_t * facelet_in)
         }
 
     }
-    free(cached_facelets);
     goto DUMP_CACHE;
 
 ERR:
@@ -1283,9 +1444,14 @@ DUMP_CACHE:
     DEBUG("----------------------------------");
 #endif
 
+    free(cached_facelets);
+
     if (remove_facelet)
         facelet_free(facelet_in);
 
+    if (ret == -1)
+        facemgr_start_reattempts(facemgr);
+
     return ret;
 }
 
@@ -1294,18 +1460,62 @@ int facemgr_callback(facemgr_t * facemgr, interface_cb_type_t type, void * data)
     switch(type) {
         case INTERFACE_CB_TYPE_RAISE_EVENT:
             return facemgr_on_event(facemgr, data);
+
         case INTERFACE_CB_TYPE_REGISTER_FD:
+        {
+            /* Remember fd for further release */
+            fd_callback_data_t * fd_callback_data = data;
+            interface_t * interface = (interface_t*)(fd_callback_data->owner);
+
+            interface_map_data_t * interface_map_data = NULL;
+            if (interface_map_get(&facemgr->interface_map, interface->name, &interface_map_data) < 0) {
+                ERROR("[facemgr_callback] Error getting interface map data");
+                return -1;
+            }
+            if (!interface_map_data) {
+                ERROR("[facemgr_callback] No entry in interface map data");
+                return -1;
+            }
+            interface_map_data->fds[interface_map_data->num_fds++] = fd_callback_data->fd;
+
             return facemgr->callback(facemgr->callback_owner,
                     FACEMGR_CB_TYPE_REGISTER_FD, data);
+        }
+
+        case INTERFACE_CB_TYPE_UNREGISTER_FD:
+        {
+            fd_callback_data_t * fd_callback_data = data;
+            interface_t * interface = (interface_t*)(fd_callback_data->owner);
+
+            interface_map_data_t * interface_map_data = NULL;
+            if (interface_map_get(&facemgr->interface_map, interface->name, &interface_map_data) < 0) {
+                ERROR("[facemgr_callback] Error getting interface map data");
+                return -1;
+            }
+            if (!interface_map_data) {
+                ERROR("[facemgr_callback] No entry in interface map data");
+                return -1;
+            }
+
+            for (unsigned i = 0; i < interface_map_data->num_fds; i++) {
+                if (interface_map_data->fds[i] == fd_callback_data->fd) {
+                    interface_map_data->fds[i] = interface_map_data->fds[--interface_map_data->num_fds];
+                    break;
+                }
+            }
+
+            return facemgr->callback(facemgr->callback_owner,
+                    FACEMGR_CB_TYPE_UNREGISTER_FD, data);
+        }
+
         case INTERFACE_CB_TYPE_REGISTER_TIMER:
             return facemgr->callback(facemgr->callback_owner,
                     FACEMGR_CB_TYPE_REGISTER_TIMER, data);
+
         case INTERFACE_CB_TYPE_UNREGISTER_TIMER:
             return facemgr->callback(facemgr->callback_owner,
                     FACEMGR_CB_TYPE_UNREGISTER_TIMER, data);
-        case INTERFACE_CB_TYPE_UNREGISTER_FD:
-            return facemgr->callback(facemgr->callback_owner,
-                    FACEMGR_CB_TYPE_UNREGISTER_FD, data);
+
     }
     return -1;
 }
@@ -1497,8 +1707,85 @@ facemgr_set_callback(facemgr_t * facemgr, void * callback_owner, facemgr_cb_t ca
     facemgr->callback_owner = callback_owner;
 }
 
-void facemgr_list_faces(facemgr_t * facemgr, facemgr_list_faces_cb_t cb, void * user_data)
+void facemgr_list_facelets(const facemgr_t * facemgr, facemgr_list_facelets_cb_t cb, void * user_data)
 {
-    //face_cache_iter(&facemgr->face_cache, cb, user_data);
-    facelet_cache_dump(&facemgr->facelet_cache);
+    facelet_t ** facelet_array;
+    if (!cb)
+        return;
+    int n = facelet_cache_get_array(&facemgr->facelet_cache, &facelet_array);
+    if (n < 0) {
+        ERROR("[facemgr_list_facelets] Could not retrieve facelets in cache");
+        return;
+    }
+    for (unsigned i = 0; i < n; i++) {
+        facelet_t * facelet = facelet_array[i];
+        cb(facemgr, facelet, user_data);
+    }
+    free(facelet_array);
+}
+
+int
+facemgr_list_facelets_json(const facemgr_t * facemgr, char ** buffer)
+{
+    char * cur;
+    char * s;
+    int rc;
+
+    facelet_t ** facelet_array;
+    int n = facelet_cache_get_array(&facemgr->facelet_cache, &facelet_array);
+    if (n < 0) {
+        ERROR("[facemgr_list_facelets_json] Could not retrieve facelets in cache");
+        return -1;
+    }
+    /* This should be enough for JSON overhead, refine later */
+    size_t size = 2 * n * MAXSZ_FACELET;
+    *buffer = malloc(size);
+    if (!buffer) {
+        ERROR("[facemgr_list_facelets_json] Could not allocate JSON s");
+        free(facelet_array);
+        return -1;
+    }
+    s = *buffer;
+    cur = s;
+
+    rc = snprintf(cur, s + size - cur, "{\"facelets\": [\n");
+    if (rc < 0)
+        goto ERR;
+    cur += rc;
+    if (size != 0 && cur >= s + size)
+        goto END;
+
+    for (unsigned i = 0; i < n; i++) {
+        facelet_t * facelet = facelet_array[i];
+
+        rc = facelet_snprintf_json(cur, s + size - cur, facelet, /* indent */ 1);
+        if (rc < 0)
+            goto ERR;
+        cur += rc;
+        if (size != 0 && cur >= s + size)
+            goto END;
+
+        rc = snprintf(cur, s + size - cur, (i == n-1) ? "\n" : ",\n");
+        if (rc < 0)
+            goto ERR;
+        cur += rc;
+        if (size != 0 && cur >= s + size)
+            goto END;
+    }
+    free(facelet_array);
+
+    rc = snprintf(cur, s + size - cur, "]}\n");
+    if (rc < 0)
+        goto ERR;
+    cur += rc;
+    if (size != 0 && cur >= s + size)
+        goto END;
+
+END:
+    free(facelet_array);
+    return cur - s;
+
+ERR:
+    free(facelet_array);
+    return rc;
 }