X-Git-Url: https://git.octo.it/?p=collectd.git;a=blobdiff_plain;f=src%2Fconnectivity.c;h=45b65aab5b09c1c5ba35110bbff618f6144de153;hp=a91b57df7e3021b3d912a9eb48bea521cf37cd70;hb=48efd3deb4c9139fd060ff3d289896e9031bcc7c;hpb=61a29253f72ffe706f8d4227d2737ce984f0110d

diff --git a/src/connectivity.c b/src/connectivity.c
index a91b57df..45b65aab 100644
--- a/src/connectivity.c
+++ b/src/connectivity.c
@@ -27,8 +27,9 @@
 
 #include "collectd.h"
 
-#include "common.h"
 #include "plugin.h"
+#include "utils/common/common.h"
+#include "utils/ignorelist/ignorelist.h"
 #include "utils_complain.h"
 
 #include <asm/types.h>
@@ -93,13 +94,14 @@
 /*
  * Private data types
  */
+
 struct interface_list_s {
   char *interface;
 
   uint32_t status;
   uint32_t prev_status;
   uint32_t sent;
-  long long unsigned int timestamp;
+  cdtime_t timestamp;
 
   struct interface_list_s *next;
 };
@@ -108,18 +110,25 @@ typedef struct interface_list_s interface_list_t;
 /*
  * Private variables
  */
-static interface_list_t *interface_list_head = NULL;
-static int monitor_all_interfaces = 0;
 
-static int connectivity_thread_loop = 0;
-static int connectivity_thread_error = 0;
-static pthread_t connectivity_thread_id;
-static pthread_mutex_t connectivity_lock = PTHREAD_MUTEX_INITIALIZER;
+static ignorelist_t *ignorelist = NULL;
+
+static interface_list_t *interface_list_head = NULL;
+static int monitor_all_interfaces = 1;
+
+static int connectivity_netlink_thread_loop = 0;
+static int connectivity_netlink_thread_error = 0;
+static pthread_t connectivity_netlink_thread_id;
+static int connectivity_dequeue_thread_loop = 0;
+static pthread_t connectivity_dequeue_thread_id;
+static pthread_mutex_t connectivity_threads_lock = PTHREAD_MUTEX_INITIALIZER;
+static pthread_mutex_t connectivity_data_lock = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t connectivity_cond = PTHREAD_COND_INITIALIZER;
-static struct mnl_socket *sock;
+static int nl_sock = -1;
 static int event_id = 0;
+static int statuses_to_send = 0;
 
-static const char *config_keys[] = {"Interface"};
+static const char *config_keys[] = {"Interface", "IgnoreSelected"};
 static int config_keys_num = STATIC_ARRAY_SIZE(config_keys);
 
 /*
@@ -127,15 +136,13 @@ static int config_keys_num = STATIC_ARRAY_SIZE(config_keys);
  */
 
 static int gen_message_payload(int state, int old_state, const char *interface,
-                               long long unsigned int timestamp, char **buf) {
+                               cdtime_t timestamp, char **buf) {
   const unsigned char *buf2;
   yajl_gen g;
   char json_str[DATA_MAX_NAME_LEN];
 
 #if !defined(HAVE_YAJL_V2)
-  yajl_gen_config conf = {};
-
-  conf.beautify = 0;
+  yajl_gen_config conf = {0};
 #endif
 
 #if HAVE_YAJL_V2
@@ -170,9 +177,9 @@ static int gen_message_payload(int state, int old_state, const char *interface,
     goto err;
 
   event_id = event_id + 1;
-  int event_id_len = sizeof(char) * sizeof(int) * 4 + 1;
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, event_id_len, "%d", event_id);
+  if (snprintf(json_str, sizeof(json_str), "%d", event_id) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_number(g, json_str, strlen(json_str)) != yajl_gen_status_ok) {
     goto err;
@@ -184,15 +191,11 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  int event_name_len = 0;
-  event_name_len = event_name_len + strlen(interface);    // interface name
-  event_name_len = event_name_len + (state == 0 ? 4 : 2); // "down" or "up"
-  event_name_len =
-      event_name_len + 12; // "interface", 2 spaces and null-terminator
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, event_name_len, "interface %s %s", interface,
-           (state == 0 ? CONNECTIVITY_EVENT_NAME_DOWN_VALUE
-                       : CONNECTIVITY_EVENT_NAME_UP_VALUE));
+  if (snprintf(json_str, sizeof(json_str), "interface %s %s", interface,
+               (state == 0 ? CONNECTIVITY_EVENT_NAME_DOWN_VALUE
+                           : CONNECTIVITY_EVENT_NAME_UP_VALUE)) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_string(g, (u_char *)json_str, strlen(json_str)) !=
       yajl_gen_status_ok) {
@@ -205,11 +208,10 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  int last_epoch_microsec_len =
-      sizeof(char) * sizeof(long long unsigned int) * 4 + 1;
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, last_epoch_microsec_len, "%llu",
-           (long long unsigned int)CDTIME_T_TO_US(cdtime()));
+  if (snprintf(json_str, sizeof(json_str), "%" PRIu64,
+               CDTIME_T_TO_US(cdtime())) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_number(g, json_str, strlen(json_str)) != yajl_gen_status_ok) {
     goto err;
@@ -264,11 +266,10 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  int start_epoch_microsec_len =
-      sizeof(char) * sizeof(long long unsigned int) * 4 + 1;
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, start_epoch_microsec_len, "%llu",
-           (long long unsigned int)timestamp);
+  if (snprintf(json_str, sizeof(json_str), "%" PRIu64,
+               CDTIME_T_TO_US(timestamp)) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_number(g, json_str, strlen(json_str)) != yajl_gen_status_ok) {
     goto err;
@@ -305,10 +306,11 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       (state == 0 ? strlen(CONNECTIVITY_NEW_STATE_FIELD_DOWN_VALUE)
                   : strlen(CONNECTIVITY_NEW_STATE_FIELD_UP_VALUE));
 
-  if (yajl_gen_string(
-          g, (u_char *)(state == 0 ? CONNECTIVITY_NEW_STATE_FIELD_DOWN_VALUE
-                                   : CONNECTIVITY_NEW_STATE_FIELD_UP_VALUE),
-          new_state_len) != yajl_gen_status_ok)
+  if (yajl_gen_string(g,
+                      (u_char *)(state == 0
+                                     ? CONNECTIVITY_NEW_STATE_FIELD_DOWN_VALUE
+                                     : CONNECTIVITY_NEW_STATE_FIELD_UP_VALUE),
+                      new_state_len) != yajl_gen_status_ok)
     goto err;
 
   // oldState
@@ -321,10 +323,11 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       (old_state == 0 ? strlen(CONNECTIVITY_OLD_STATE_FIELD_DOWN_VALUE)
                       : strlen(CONNECTIVITY_OLD_STATE_FIELD_UP_VALUE));
 
-  if (yajl_gen_string(
-          g, (u_char *)(old_state == 0 ? CONNECTIVITY_OLD_STATE_FIELD_DOWN_VALUE
-                                       : CONNECTIVITY_OLD_STATE_FIELD_UP_VALUE),
-          old_state_len) != yajl_gen_status_ok)
+  if (yajl_gen_string(g,
+                      (u_char *)(old_state == 0
+                                     ? CONNECTIVITY_OLD_STATE_FIELD_DOWN_VALUE
+                                     : CONNECTIVITY_OLD_STATE_FIELD_UP_VALUE),
+                      old_state_len) != yajl_gen_status_ok)
     goto err;
 
   // stateChangeFieldsVersion
@@ -349,20 +352,23 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  if (yajl_gen_map_close(g) != yajl_gen_status_ok)
+  // close state change and header fields
+  if (yajl_gen_map_close(g) != yajl_gen_status_ok ||
+      yajl_gen_map_close(g) != yajl_gen_status_ok)
     goto err;
 
   // *** END state change fields ***
 
-  if (yajl_gen_map_close(g) != yajl_gen_status_ok)
-    goto err;
-
   if (yajl_gen_get_buf(g, &buf2, &len) != yajl_gen_status_ok)
     goto err;
 
-  *buf = malloc(strlen((char *)buf2) + 1);
+  *buf = strdup((char *)buf2);
 
-  sstrncpy(*buf, (char *)buf2, strlen((char *)buf2) + 1);
+  if (*buf == NULL) {
+    ERROR("connectivity plugin: strdup failed during gen_message_payload: %s",
+          STRERRNO);
+    goto err;
+  }
 
   yajl_gen_free(g);
 
@@ -376,30 +382,26 @@ err:
 
 static interface_list_t *add_interface(const char *interface, int status,
                                        int prev_status) {
-  interface_list_t *il;
-  char *interface2;
+  interface_list_t *il = calloc(1, sizeof(*il));
 
-  il = malloc(sizeof(*il));
   if (il == NULL) {
-    char errbuf[1024];
-    ERROR("connectivity plugin: malloc failed during add_interface: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("connectivity plugin: calloc failed during add_interface: %s",
+          STRERRNO);
     return NULL;
   }
 
-  interface2 = strdup(interface);
+  char *interface2 = strdup(interface);
   if (interface2 == NULL) {
-    char errbuf[1024];
     sfree(il);
     ERROR("connectivity plugin: strdup failed during add_interface: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+          STRERRNO);
     return NULL;
   }
 
   il->interface = interface2;
   il->status = status;
   il->prev_status = prev_status;
-  il->timestamp = (long long unsigned int)CDTIME_T_TO_US(cdtime());
+  il->timestamp = cdtime();
   il->sent = 0;
   il->next = interface_list_head;
   interface_list_head = il;
@@ -410,14 +412,10 @@ static interface_list_t *add_interface(const char *interface, int status,
 }
 
 static int connectivity_link_state(struct nlmsghdr *msg) {
-  int retval = 0;
-  struct ifinfomsg *ifi = mnl_nlmsg_get_payload(msg);
-  struct nlattr *attr;
-  const char *dev = NULL;
+  pthread_mutex_lock(&connectivity_data_lock);
 
-  pthread_mutex_lock(&connectivity_lock);
-
-  interface_list_t *il;
+  struct nlattr *attr;
+  struct ifinfomsg *ifi = mnl_nlmsg_get_payload(msg);
 
   /* Scan attribute list for device name. */
   mnl_attr_for_each(attr, msg, sizeof(*ifi)) {
@@ -428,237 +426,423 @@ static int connectivity_link_state(struct nlmsghdr *msg) {
       ERROR("connectivity plugin: connectivity_link_state: IFLA_IFNAME "
             "mnl_attr_validate "
             "failed.");
-      pthread_mutex_unlock(&connectivity_lock);
+      pthread_mutex_unlock(&connectivity_data_lock);
       return MNL_CB_ERROR;
     }
 
-    dev = mnl_attr_get_str(attr);
+    const char *dev = mnl_attr_get_str(attr);
+
+    // Check the list of interfaces we should monitor, if we've chosen
+    // a subset.  If we don't care about this one, abort.
+    if (ignorelist_match(ignorelist, dev) != 0) {
+      DEBUG("connectivity plugin: Ignoring link state change for unmonitored "
+            "interface: %s",
+            dev);
+      break;
+    }
+
+    interface_list_t *il = NULL;
 
     for (il = interface_list_head; il != NULL; il = il->next)
       if (strcmp(dev, il->interface) == 0)
         break;
 
-    if (il == NULL && monitor_all_interfaces == 0) {
-      DEBUG("connectivity plugin: Ignoring link state change for unmonitored "
-            "interface: %s",
-            dev);
-    } else {
-      uint32_t prev_status;
+    if (il == NULL) {
+      // We haven't encountered this interface yet, so add it to the linked list
+      il = add_interface(dev, LINK_STATE_UNKNOWN, LINK_STATE_UNKNOWN);
 
       if (il == NULL) {
-        // We're monitoring all interfaces and we haven't encountered this one
-        // yet, so add it to the linked list
-        il = add_interface(dev, LINK_STATE_UNKNOWN, LINK_STATE_UNKNOWN);
-
-        if (il == NULL) {
-          ERROR("connectivity plugin: unable to add interface %s during "
-                "connectivity_link_state",
-                dev);
-          return MNL_CB_ERROR;
-        }
+        ERROR("connectivity plugin: unable to add interface %s during "
+              "connectivity_link_state",
+              dev);
+        return MNL_CB_ERROR;
       }
+    }
 
-      prev_status = il->status;
-      il->status =
-          ((ifi->ifi_flags & IFF_RUNNING) ? LINK_STATE_UP : LINK_STATE_DOWN);
-      il->timestamp = (long long unsigned int)CDTIME_T_TO_US(cdtime());
-
-      // If the new status is different than the previous status,
-      // store the previous status and set sent to zero
-      if (il->status != prev_status) {
-        il->prev_status = prev_status;
-        il->sent = 0;
-      }
+    uint32_t prev_status = il->status;
+    il->status =
+        ((ifi->ifi_flags & IFF_RUNNING) ? LINK_STATE_UP : LINK_STATE_DOWN);
+    il->timestamp = cdtime();
 
-      DEBUG("connectivity plugin (%llu): Interface %s status is now %s",
-            il->timestamp, dev,
-            ((ifi->ifi_flags & IFF_RUNNING) ? "UP" : "DOWN"));
+    // If the new status is different than the previous status,
+    // store the previous status and set sent to zero, and set the
+    // global flag to indicate there are statuses to dispatch
+    if (il->status != prev_status) {
+      il->prev_status = prev_status;
+      il->sent = 0;
+      statuses_to_send = 1;
     }
 
+    DEBUG("connectivity plugin (%llu): Interface %s status is now %s",
+          (unsigned long long)il->timestamp, dev,
+          ((ifi->ifi_flags & IFF_RUNNING) ? "UP" : "DOWN"));
+
     // no need to loop again, we found the interface name attr
     // (otherwise the first if-statement in the loop would
     // have moved us on with 'continue')
     break;
   }
 
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_data_lock);
 
-  return retval;
+  return 0;
 }
 
 static int msg_handler(struct nlmsghdr *msg) {
-  switch (msg->nlmsg_type) {
-  case RTM_NEWADDR:
-  case RTM_DELADDR:
-  case RTM_NEWROUTE:
-  case RTM_DELROUTE:
-  case RTM_DELLINK:
-    // Not of interest in current version
-    break;
-  case RTM_NEWLINK:
-    connectivity_link_state(msg);
-    break;
-  default:
-    ERROR("connectivity plugin: msg_handler: Unknown netlink nlmsg_type %d\n",
-          msg->nlmsg_type);
-    break;
+  // We are only interested in RTM_NEWLINK messages
+  if (msg->nlmsg_type != RTM_NEWLINK) {
+    return 0;
   }
-  return 0;
+  return connectivity_link_state(msg);
 }
 
-static int read_event(struct mnl_socket *nl,
-                      int (*msg_handler)(struct nlmsghdr *)) {
-  int status;
+static int read_event(int (*msg_handler)(struct nlmsghdr *)) {
   int ret = 0;
-  char buf[4096];
-  struct nlmsghdr *h;
+  int recv_flags = MSG_DONTWAIT;
 
-  if (nl == NULL)
-    return ret;
+  if (nl_sock == -1 || msg_handler == NULL)
+    return EINVAL;
 
-  status = mnl_socket_recvfrom(nl, buf, sizeof(buf));
+  while (42) {
+    pthread_mutex_lock(&connectivity_threads_lock);
 
-  if (status < 0) {
-    /* Socket non-blocking so bail out once we have read everything */
-    if (errno == EWOULDBLOCK || errno == EAGAIN)
+    if (connectivity_netlink_thread_loop <= 0) {
+      pthread_mutex_unlock(&connectivity_threads_lock);
       return ret;
+    }
 
-    /* Anything else is an error */
-    ERROR("connectivity plugin: read_event: Error mnl_socket_recvfrom: %d\n",
-          status);
-    return status;
-  }
+    pthread_mutex_unlock(&connectivity_threads_lock);
 
-  if (status == 0) {
-    DEBUG("connectivity plugin: read_event: EOF\n");
-  }
+    char buf[4096];
+    int status = recv(nl_sock, buf, sizeof(buf), recv_flags);
 
-  /* We need to handle more than one message per 'recvmsg' */
-  for (h = (struct nlmsghdr *)buf; NLMSG_OK(h, (unsigned int)status);
-       h = NLMSG_NEXT(h, status)) {
-    /* Finish reading */
-    if (h->nlmsg_type == NLMSG_DONE)
-      return ret;
+    if (status < 0) {
+
+      // If there were no more messages to drain from the socket,
+      // then signal the dequeue thread and allow it to dispatch
+      // any saved interface status changes.  Then continue, but
+      // block and wait for new messages
+      if (errno == EWOULDBLOCK || errno == EAGAIN) {
+        pthread_cond_signal(&connectivity_cond);
 
-    /* Message is some kind of error */
-    if (h->nlmsg_type == NLMSG_ERROR) {
-      ERROR("connectivity plugin: read_event: Message is an error\n");
-      return -1; // Error
+        recv_flags = 0;
+        continue;
+      }
+
+      if (errno == EINTR) {
+        // Interrupt, so just continue and try again
+        continue;
+      }
+
+      /* Anything else is an error */
+      ERROR("connectivity plugin: read_event: Error recv: %d", status);
+      return status;
     }
 
-    /* Call message handler */
-    if (msg_handler) {
-      ret = (*msg_handler)(h);
-      if (ret < 0) {
-        ERROR("connectivity plugin: read_event: Message handler error %d\n",
-              ret);
+    // Message received successfully, so we'll stop blocking on the
+    // receive call for now (until we get a "would block" error, which
+    // will be handled above)
+    recv_flags = MSG_DONTWAIT;
+
+    if (status == 0) {
+      DEBUG("connectivity plugin: read_event: EOF");
+    }
+
+    /* We need to handle more than one message per 'recvmsg' */
+    for (struct nlmsghdr *h = (struct nlmsghdr *)buf;
+         NLMSG_OK(h, (unsigned int)status); h = NLMSG_NEXT(h, status)) {
+      /* Finish reading */
+      if (h->nlmsg_type == NLMSG_DONE)
         return ret;
+
+      /* Message is some kind of error */
+      if (h->nlmsg_type == NLMSG_ERROR) {
+        struct nlmsgerr *l_err = (struct nlmsgerr *)NLMSG_DATA(h);
+        ERROR("connectivity plugin: read_event: Message is an error: %d",
+              l_err->error);
+        return -1; // Error
+      }
+
+      /* Call message handler */
+      if (msg_handler) {
+        ret = (*msg_handler)(h);
+        if (ret < 0) {
+          ERROR("connectivity plugin: read_event: Message handler error %d",
+                ret);
+          return ret;
+        }
+      } else {
+        ERROR("connectivity plugin: read_event: Error NULL message handler");
+        return -1;
       }
-    } else {
-      ERROR("connectivity plugin: read_event: Error NULL message handler\n");
-      return -1;
     }
   }
 
   return ret;
 }
 
-static void *connectivity_thread(void *arg) /* {{{ */
+static void connectivity_dispatch_notification(const char *interface,
+                                               gauge_t value, gauge_t old_value,
+                                               cdtime_t timestamp) {
+
+  notification_t n = {
+      .severity = (value == LINK_STATE_UP ? NOTIF_OKAY : NOTIF_FAILURE),
+      .time = cdtime(),
+      .plugin = "connectivity",
+      .type = "gauge",
+      .type_instance = "interface_status",
+  };
+
+  sstrncpy(n.host, hostname_g, sizeof(n.host));
+  sstrncpy(n.plugin_instance, interface, sizeof(n.plugin_instance));
+
+  char *buf = NULL;
+
+  gen_message_payload(value, old_value, interface, timestamp, &buf);
+
+  int status = plugin_notification_meta_add_string(&n, "ves", buf);
+
+  if (status < 0) {
+    sfree(buf);
+    ERROR("connectivity plugin: unable to set notification VES metadata: %s",
+          STRERRNO);
+    return;
+  }
+
+  DEBUG("connectivity plugin: notification VES metadata: %s",
+        n.meta->nm_value.nm_string);
+
+  DEBUG("connectivity plugin: dispatching state %d for interface %s",
+        (int)value, interface);
+
+  plugin_dispatch_notification(&n);
+  plugin_notification_meta_free(n.meta);
+
+  // strdup'd in gen_message_payload
+  if (buf != NULL)
+    sfree(buf);
+}
+
+// NOTE: Caller MUST hold connectivity_data_lock when calling this function
+static void send_interface_status() {
+  for (interface_list_t *il = interface_list_head; il != NULL;
+       il = il->next) /* {{{ */
+  {
+    uint32_t status = il->status;
+    uint32_t prev_status = il->prev_status;
+    uint32_t sent = il->sent;
+
+    if (status != prev_status && sent == 0) {
+      connectivity_dispatch_notification(il->interface, status, prev_status,
+                                         il->timestamp);
+      il->sent = 1;
+    }
+  } /* }}} for (il = interface_list_head; il != NULL; il = il->next) */
+
+  statuses_to_send = 0;
+}
+
+static void read_interface_status() /* {{{ */
 {
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_data_lock);
 
-  while (connectivity_thread_loop > 0) {
-    int status;
+  // If we don't have any interface statuses to dispatch,
+  // then we wait until signalled
+  if (!statuses_to_send)
+    pthread_cond_wait(&connectivity_cond, &connectivity_data_lock);
 
-    pthread_mutex_unlock(&connectivity_lock);
+  send_interface_status();
 
-    status = read_event(sock, msg_handler);
+  pthread_mutex_unlock(&connectivity_data_lock);
+} /* }}} int *read_interface_status */
 
-    pthread_mutex_lock(&connectivity_lock);
+static void *connectivity_netlink_thread(void *arg) /* {{{ */
+{
+  pthread_mutex_lock(&connectivity_threads_lock);
+
+  while (connectivity_netlink_thread_loop > 0) {
+    pthread_mutex_unlock(&connectivity_threads_lock);
+
+    int status = read_event(msg_handler);
+
+    pthread_mutex_lock(&connectivity_threads_lock);
 
     if (status < 0) {
-      connectivity_thread_error = 1;
+      connectivity_netlink_thread_error = 1;
       break;
     }
+  } /* while (connectivity_netlink_thread_loop > 0) */
 
-    if (connectivity_thread_loop <= 0)
-      break;
-  } /* while (connectivity_thread_loop > 0) */
+  pthread_mutex_unlock(&connectivity_threads_lock);
+
+  return (void *)0;
+} /* }}} void *connectivity_netlink_thread */
+
+static void *connectivity_dequeue_thread(void *arg) /* {{{ */
+{
+  pthread_mutex_lock(&connectivity_threads_lock);
+
+  while (connectivity_dequeue_thread_loop > 0) {
+    pthread_mutex_unlock(&connectivity_threads_lock);
+
+    read_interface_status();
+
+    pthread_mutex_lock(&connectivity_threads_lock);
+  } /* while (connectivity_dequeue_thread_loop > 0) */
 
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
   return ((void *)0);
-} /* }}} void *connectivity_thread */
+} /* }}} void *connectivity_dequeue_thread */
+
+static int nl_connect() {
+  struct sockaddr_nl sa_nl = {
+      .nl_family = AF_NETLINK,
+      .nl_groups = RTMGRP_LINK,
+      .nl_pid = getpid(),
+  };
+
+  nl_sock = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
+  if (nl_sock == -1) {
+    ERROR("connectivity plugin: socket open failed: %s", STRERRNO);
+    return -1;
+  }
 
-static int start_thread(void) /* {{{ */
-{
-  int status;
+  int rc = bind(nl_sock, (struct sockaddr *)&sa_nl, sizeof(sa_nl));
+  if (rc == -1) {
+    ERROR("connectivity plugin: socket bind failed: %s", STRERRNO);
+    close(nl_sock);
+    nl_sock = -1;
+    return -1;
+  }
 
-  pthread_mutex_lock(&connectivity_lock);
+  return 0;
+}
 
-  if (connectivity_thread_loop != 0) {
-    pthread_mutex_unlock(&connectivity_lock);
-    return (0);
+static int start_netlink_thread(void) /* {{{ */
+{
+  pthread_mutex_lock(&connectivity_threads_lock);
+
+  if (connectivity_netlink_thread_loop != 0) {
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return 0;
   }
 
-  connectivity_thread_loop = 1;
-  connectivity_thread_error = 0;
+  connectivity_netlink_thread_loop = 1;
+  connectivity_netlink_thread_error = 0;
 
-  if (sock == NULL) {
-    sock = mnl_socket_open(NETLINK_ROUTE);
-    if (sock == NULL) {
-      ERROR(
-          "connectivity plugin: connectivity_thread: mnl_socket_open failed.");
-      pthread_mutex_unlock(&connectivity_lock);
-      return (-1);
-    }
+  int status;
 
-    if (mnl_socket_bind(sock, RTMGRP_LINK, MNL_SOCKET_AUTOPID) < 0) {
-      ERROR(
-          "connectivity plugin: connectivity_thread: mnl_socket_bind failed.");
-      pthread_mutex_unlock(&connectivity_lock);
-      return (1);
+  if (nl_sock == -1) {
+    status = nl_connect();
+
+    if (status != 0) {
+      pthread_mutex_unlock(&connectivity_threads_lock);
+      return status;
     }
   }
 
-  status = plugin_thread_create(&connectivity_thread_id, /* attr = */ NULL,
-                                connectivity_thread,
+  status = plugin_thread_create(&connectivity_netlink_thread_id,
+                                /* attr = */ NULL, connectivity_netlink_thread,
                                 /* arg = */ (void *)0, "connectivity");
   if (status != 0) {
-    connectivity_thread_loop = 0;
+    connectivity_netlink_thread_loop = 0;
     ERROR("connectivity plugin: Starting thread failed.");
-    pthread_mutex_unlock(&connectivity_lock);
-    mnl_socket_close(sock);
-    return (-1);
+    pthread_mutex_unlock(&connectivity_threads_lock);
+
+    int status2 = close(nl_sock);
+
+    if (status2 != 0) {
+      ERROR("connectivity plugin: failed to close socket %d: %d (%s)", nl_sock,
+            status2, STRERRNO);
+    }
+
+    nl_sock = -1;
+
+    return -1;
   }
 
-  pthread_mutex_unlock(&connectivity_lock);
-  return (0);
-} /* }}} int start_thread */
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
-static int stop_thread(int shutdown) /* {{{ */
+  return status;
+}
+
+static int start_dequeue_thread(void) /* {{{ */
 {
-  int status;
+  pthread_mutex_lock(&connectivity_threads_lock);
+
+  if (connectivity_dequeue_thread_loop != 0) {
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return 0;
+  }
+
+  connectivity_dequeue_thread_loop = 1;
+
+  int status =
+      plugin_thread_create(&connectivity_dequeue_thread_id,
+                           /* attr = */ NULL, connectivity_dequeue_thread,
+                           /* arg = */ (void *)0, "connectivity");
+  if (status != 0) {
+    connectivity_dequeue_thread_loop = 0;
+    ERROR("connectivity plugin: Starting dequeue thread failed.");
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return -1;
+  }
+
+  pthread_mutex_unlock(&connectivity_threads_lock);
+
+  return status;
+} /* }}} int start_dequeue_thread */
+
+static int start_threads(void) /* {{{ */
+{
+  int status = start_netlink_thread();
+  int status2 = start_dequeue_thread();
+
+  if (status != 0)
+    return status;
+  else
+    return status2;
+} /* }}} int start_threads */
+
+static int stop_netlink_thread(int shutdown) /* {{{ */
+{
+  int socket_status;
 
-  if (sock != NULL)
-    mnl_socket_close(sock);
+  if (nl_sock != -1) {
+    socket_status = close(nl_sock);
+    if (socket_status != 0) {
+      ERROR("connectivity plugin: failed to close socket %d: %d (%s)", nl_sock,
+            socket_status, STRERRNO);
+    }
 
-  pthread_mutex_lock(&connectivity_lock);
+    nl_sock = -1;
+  } else
+    socket_status = 0;
 
-  if (connectivity_thread_loop == 0) {
-    pthread_mutex_unlock(&connectivity_lock);
-    return (-1);
+  pthread_mutex_lock(&connectivity_threads_lock);
+
+  if (connectivity_netlink_thread_loop == 0) {
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    // Thread has already been terminated, nothing more to attempt
+    return socket_status;
   }
 
-  connectivity_thread_loop = 0;
+  // Set thread termination status
+  connectivity_netlink_thread_loop = 0;
+  pthread_mutex_unlock(&connectivity_threads_lock);
+
+  // Let threads waiting on access to the interface list know to move
+  // on such that they'll see the thread's termination status
   pthread_cond_broadcast(&connectivity_cond);
-  pthread_mutex_unlock(&connectivity_lock);
+
+  int thread_status;
 
   if (shutdown == 1) {
     // Since the thread is blocking, calling pthread_join
     // doesn't actually succeed in stopping it.  It will stick around
     // until a NETLINK message is received on the socket (at which
-    // it will realize that "connectivity_thread_loop" is 0 and will
+    // it will realize that "connectivity_netlink_thread_loop" is 0 and will
     // break out of the read loop and be allowed to die).  This is
     // fine when the process isn't supposed to be exiting, but in
     // the case of a process shutdown, we don't want to have an
@@ -666,117 +850,138 @@ static int stop_thread(int shutdown) /* {{{ */
     // the case of a shutdown is just assures that the thread is
     // gone and that the process has been fully terminated.
 
-    DEBUG("connectivity plugin: Canceling thread for process shutdown");
+    DEBUG("connectivity plugin: Canceling netlink thread for process shutdown");
 
-    status = pthread_cancel(connectivity_thread_id);
+    thread_status = pthread_cancel(connectivity_netlink_thread_id);
 
-    if (status != 0) {
-      ERROR("connectivity plugin: Unable to cancel thread: %d", status);
-      status = -1;
-    }
+    if (thread_status != 0 && thread_status != ESRCH) {
+      ERROR("connectivity plugin: Unable to cancel netlink thread: %d",
+            thread_status);
+      thread_status = -1;
+    } else
+      thread_status = 0;
   } else {
-    status = pthread_join(connectivity_thread_id, /* return = */ NULL);
-    if (status != 0) {
-      ERROR("connectivity plugin: Stopping thread failed.");
-      status = -1;
-    }
+    thread_status =
+        pthread_join(connectivity_netlink_thread_id, /* return = */ NULL);
+    if (thread_status != 0 && thread_status != ESRCH) {
+      ERROR("connectivity plugin: Stopping netlink thread failed: %d",
+            thread_status);
+      thread_status = -1;
+    } else
+      thread_status = 0;
   }
 
-  pthread_mutex_lock(&connectivity_lock);
-  memset(&connectivity_thread_id, 0, sizeof(connectivity_thread_id));
-  connectivity_thread_error = 0;
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
+  memset(&connectivity_netlink_thread_id, 0,
+         sizeof(connectivity_netlink_thread_id));
+  connectivity_netlink_thread_error = 0;
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
-  DEBUG("connectivity plugin: Finished requesting stop of thread");
+  DEBUG("connectivity plugin: Finished requesting stop of netlink thread");
 
-  return (status);
-} /* }}} int stop_thread */
+  if (socket_status != 0)
+    return socket_status;
+  else
+    return thread_status;
+}
 
-static int connectivity_init(void) /* {{{ */
+static int stop_dequeue_thread() /* {{{ */
 {
-  if (interface_list_head == NULL) {
-    NOTICE("connectivity plugin: No interfaces have been selected, so all will "
-           "be monitored");
-    monitor_all_interfaces = 1;
+  pthread_mutex_lock(&connectivity_threads_lock);
+
+  if (connectivity_dequeue_thread_loop == 0) {
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return -1;
   }
 
-  return (start_thread());
-} /* }}} int connectivity_init */
+  // Set thread termination status
+  connectivity_dequeue_thread_loop = 0;
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
-static int connectivity_config(const char *key, const char *value) /* {{{ */
-{
-  if (strcasecmp(key, "Interface") == 0) {
-    interface_list_t *il =
-        add_interface(value, LINK_STATE_UNKNOWN, LINK_STATE_UNKNOWN);
-    if (il == NULL) {
-      ERROR("connectivity plugin: unable to add interface %s during "
-            "connectivity_init",
-            value);
-      return (-1);
-    }
-  } else {
-    return (-1);
-  }
+  // Let threads waiting on access to the interface list know to move
+  // on such that they'll see the threads termination status
+  pthread_cond_broadcast(&connectivity_cond);
 
-  return (0);
-} /* }}} int connectivity_config */
+  // Calling pthread_cancel here just assures that the thread is
+  // gone and that the process has been fully terminated.
 
-static void connectivity_dispatch_notification(
-    const char *interface, const char *type, /* {{{ */
-    gauge_t value, gauge_t old_value, long long unsigned int timestamp) {
-  char *buf = NULL;
-  notification_t n = {
-      NOTIF_FAILURE, cdtime(), "", "", "connectivity", "", "", "", NULL};
+  DEBUG("connectivity plugin: Canceling dequeue thread for process shutdown");
 
-  if (value == LINK_STATE_UP)
-    n.severity = NOTIF_OKAY;
+  int status = pthread_cancel(connectivity_dequeue_thread_id);
 
-  char hostname[1024];
-  gethostname(hostname, sizeof(hostname));
+  if (status != 0 && status != ESRCH) {
+    ERROR("connectivity plugin: Unable to cancel dequeue thread: %d", status);
+    status = -1;
+  } else
+    status = 0;
 
-  sstrncpy(n.host, hostname, sizeof(n.host));
-  sstrncpy(n.plugin_instance, interface, sizeof(n.plugin_instance));
-  sstrncpy(n.type, "gauge", sizeof(n.type));
-  sstrncpy(n.type_instance, "interface_status", sizeof(n.type_instance));
+  pthread_mutex_lock(&connectivity_threads_lock);
+  memset(&connectivity_dequeue_thread_id, 0,
+         sizeof(connectivity_dequeue_thread_id));
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
-  gen_message_payload(value, old_value, interface, timestamp, &buf);
+  DEBUG("connectivity plugin: Finished requesting stop of dequeue thread");
 
-  notification_meta_t *m = calloc(1, sizeof(*m));
+  return status;
+} /* }}} int stop_dequeue_thread */
 
-  if (m == NULL) {
-    char errbuf[1024];
-    sfree(buf);
-    ERROR("connectivity plugin: unable to allocate metadata: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
-    return;
+static int stop_threads() /* {{{ */
+{
+  int status = stop_netlink_thread(1);
+  int status2 = stop_dequeue_thread();
+
+  if (status != 0)
+    return status;
+  else
+    return status2;
+} /* }}} int stop_threads */
+
+static int connectivity_init(void) /* {{{ */
+{
+  if (monitor_all_interfaces) {
+    NOTICE("connectivity plugin: No interfaces have been selected, so all will "
+           "be monitored");
   }
 
-  sstrncpy(m->name, "ves", sizeof(m->name));
-  m->nm_value.nm_string = sstrdup(buf);
-  m->type = NM_TYPE_STRING;
-  n.meta = m;
+  return start_threads();
+} /* }}} int connectivity_init */
 
-  DEBUG("connectivity plugin: notification message: %s",
-        n.meta->nm_value.nm_string);
+static int connectivity_config(const char *key, const char *value) /* {{{ */
+{
+  if (ignorelist == NULL) {
+    ignorelist = ignorelist_create(/* invert = */ 1);
 
-  DEBUG("connectivity plugin: dispatching state %d for interface %s",
-        (int)value, interface);
+    if (ignorelist == NULL)
+      return -1;
+  }
 
-  plugin_dispatch_notification(&n);
-  plugin_notification_meta_free(n.meta);
+  if (strcasecmp(key, "Interface") == 0) {
+    ignorelist_add(ignorelist, value);
+    monitor_all_interfaces = 0;
+  } else if (strcasecmp(key, "IgnoreSelected") == 0) {
+    int invert = 1;
+    if (IS_TRUE(value))
+      invert = 0;
+    ignorelist_set_invert(ignorelist, invert);
+  } else {
+    return -1;
+  }
 
-  // malloc'd in gen_message_payload
-  if (buf != NULL)
-    sfree(buf);
-}
+  return 0;
+} /* }}} int connectivity_config */
 
 static int connectivity_read(void) /* {{{ */
 {
-  if (connectivity_thread_error != 0) {
-    ERROR("connectivity plugin: The interface thread had a problem. Restarting "
+  pthread_mutex_lock(&connectivity_threads_lock);
+
+  if (connectivity_netlink_thread_error != 0) {
+
+    pthread_mutex_unlock(&connectivity_threads_lock);
+
+    ERROR("connectivity plugin: The netlink thread had a problem. Restarting "
           "it.");
 
-    stop_thread(0);
+    stop_netlink_thread(0);
 
     for (interface_list_t *il = interface_list_head; il != NULL;
          il = il->next) {
@@ -785,45 +990,23 @@ static int connectivity_read(void) /* {{{ */
       il->sent = 0;
     }
 
-    start_thread();
+    start_netlink_thread();
 
-    return (-1);
-  } /* if (connectivity_thread_error != 0) */
+    return -1;
+  } /* if (connectivity_netlink_thread_error != 0) */
 
-  for (interface_list_t *il = interface_list_head; il != NULL;
-       il = il->next) /* {{{ */
-  {
-    uint32_t status;
-    uint32_t prev_status;
-    uint32_t sent;
-
-    pthread_mutex_lock(&connectivity_lock);
-
-    status = il->status;
-    prev_status = il->prev_status;
-    sent = il->sent;
-
-    if (status != prev_status && sent == 0) {
-      connectivity_dispatch_notification(il->interface, "gauge", status,
-                                         prev_status, il->timestamp);
-      il->sent = 1;
-    }
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
-    pthread_mutex_unlock(&connectivity_lock);
-  } /* }}} for (il = interface_list_head; il != NULL; il = il->next) */
-
-  return (0);
+  return 0;
 } /* }}} int connectivity_read */
 
 static int connectivity_shutdown(void) /* {{{ */
 {
-  interface_list_t *il;
-
   DEBUG("connectivity plugin: Shutting down thread.");
-  if (stop_thread(1) < 0)
-    return (-1);
 
-  il = interface_list_head;
+  int status = stop_threads();
+
+  interface_list_t *il = interface_list_head;
   while (il != NULL) {
     interface_list_t *il_next;
 
@@ -835,7 +1018,9 @@ static int connectivity_shutdown(void) /* {{{ */
     il = il_next;
   }
 
-  return (0);
+  ignorelist_free(ignorelist);
+
+  return status;
 } /* }}} int connectivity_shutdown */
 
 void module_register(void) {