#include "gnunet_util_lib.h"
#include "sensor.h"
#include "gnunet_peerstore_service.h"
+#include "gnunet_sensor_model_plugin.h"
#define LOG(kind,...) GNUNET_log_from (kind, "sensor-analysis",__VA_ARGS__)
*/
struct GNUNET_PEERSTORE_WatchContext *wc;
+ /*
+ * Closure for model plugin
+ */
+ void *cls;
+
};
/**
GNUNET_PEERSTORE_watch_cancel(sensor_model->wc);
sensor_model->wc = NULL;
}
+ if (NULL != sensor_model->cls)
+ {
+ model_api->destroy_model (sensor_model->cls);
+ sensor_model->cls = NULL;
+ }
+ GNUNET_free(sensor_model);
sensor_model = NULL;
}
struct SensorModel *sm;
LOG (GNUNET_ERROR_TYPE_DEBUG, "Stopping sensor analysis module.\n");
- if (NULL != model_api)
- {
- GNUNET_break (NULL == GNUNET_PLUGIN_unload (model_lib_name, model_api));
- GNUNET_free (model_lib_name);
- model_lib_name = NULL;
- }
while (NULL != models_head)
{
sm = models_head;
- destroy_sensor_model(sm);
GNUNET_CONTAINER_DLL_remove(models_head, models_tail, sm);
+ destroy_sensor_model(sm);
}
if (NULL != peerstore)
{
GNUNET_PEERSTORE_disconnect(peerstore);
peerstore = NULL;
}
+ if (NULL != model_api)
+ {
+ GNUNET_break (NULL == GNUNET_PLUGIN_unload (model_lib_name, model_api));
+ GNUNET_free (model_lib_name);
+ model_lib_name = NULL;
+ }
}
/*
struct GNUNET_PEERSTORE_Record *record,
char *emsg)
{
+ struct SensorModel *sensor_model = cls;
+ double *val;
+ int anomalous;
+
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Received a sensor value, will feed to sensor model.\n");
+ if (sizeof(double) != record->value_size)
+ {
+ LOG (GNUNET_ERROR_TYPE_ERROR,
+ _("Received an invalid sensor value."));
+ return GNUNET_YES;
+ }
+ val = (double *)(record->value);
+ anomalous = model_api->feed_model (sensor_model->cls, *val);
+ if (GNUNET_YES == anomalous)
+ {
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ "Anomaly detected, value: %f.\n",
+ *val);
+ }
+ else
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "Value non-anomalous.\n");
return GNUNET_YES;
}
sensor_model->wc = GNUNET_PEERSTORE_watch(peerstore,
"sensor", &peerid, sensor->name,
&sensor_watcher, sensor_model);
+ sensor_model->cls = model_api->create_model(model_api->cls);
GNUNET_CONTAINER_DLL_insert(models_head, models_tail, sensor_model);
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Created sensor model for `%s'.\n", sensor->name);
void *
(*create_model) (void *cls);
+ /*
+ * Destroy a model instance
+ *
+ * @param cls closure (model state)
+ */
+ void
+ (*destroy_model) (void *cls);
+
+ /*
+ * Feed a new value to a model
+ *
+ * @param cls closure (model state)
+ * @param val value to be fed to the model
+ * @return #GNUNET_YES in case of a detected outlier, #GNUNET_NO otherwise
+ */
+ int
+ (*feed_model) (void *cls, double val);
+
};
*/
const struct GNUNET_CONFIGURATION_Handle *cfg;
+ /*
+ * Number of initial readings to be used for training only
+ */
+ int training_window;
+
+ /*
+ * Number of standard deviations considered within "normal"
+ */
+ int confidence_interval;
+
};
/*
*/
struct Plugin *plugin;
+ /*
+ * Number of readings so far
+ */
+ int n;
+
+ /*
+ * Sum of readings
+ */
+ long double sum;
+
+ /*
+ * Sum square of readings
+ */
+ long double sumsq;
+
};
+static void
+update_sums (struct Model *model, double val)
+{
+ model->sum += val;
+ model->sumsq += val * val;
+ model->n ++;
+}
+
+/*
+ * Feed a new value to a model
+ *
+ * @param cls closure (model state)
+ * @param val value to be fed to the model
+ * @return #GNUNET_YES in case of a detected outlier, #GNUNET_NO otherwise
+ */
+static int
+sensor_gaussian_model_feed (void *cls, double val)
+{
+ struct Model *model = cls;
+ struct Plugin *plugin = model->plugin;
+ long double mean;
+ long double stddev;
+ long double allowed_variance;
+
+ if (model->n < plugin->training_window)
+ {
+ update_sums(model, val);
+ return GNUNET_NO;
+ }
+ mean = model->sum / model->n;
+ stddev = sqrt(
+ (model->sumsq - 2 * mean * model->sum + model->n * mean * mean)
+ /
+ (model->n - 1)
+ );
+ allowed_variance = (plugin->confidence_interval * stddev);
+ if ((val < (mean - allowed_variance)) ||
+ (val > (mean + allowed_variance)))
+ return GNUNET_YES;
+ return GNUNET_NO;
+}
+
+/*
+ * Destroy a model instance
+ *
+ * @param cls closure (model state)
+ */
+static void
+sensor_gaussian_model_destroy_model (void *cls)
+{
+ struct Model *model = cls;
+
+ GNUNET_free(model);
+}
+
+/*
+ * Create a model instance
+ *
+ * @param cls closure (plugin state)
+ * @return model state to be used for later calls
+ */
static void *
sensor_gaussian_model_create_model (void *cls)
{
static struct Plugin plugin;
const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
struct GNUNET_SENSOR_ModelFunctions *api;
+ unsigned long long num;
if (NULL != plugin.cfg)
return NULL; /* can only initialize once! */
memset (&plugin, 0, sizeof (struct Plugin));
plugin.cfg = cfg;
+ if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_number(cfg,
+ "sensor-model-gaussian", "TRAINING_WINDOW", &num))
+ {
+ LOG (GNUNET_ERROR_TYPE_ERROR,
+ _("Missing `TRAINING_WINDOW' value in configuration.\n"));
+ return NULL;
+ }
+ plugin.training_window = (int) num;
+ if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_number(cfg,
+ "sensor-model-gaussian", "CONFIDENCE_INTERVAL", &num))
+ {
+ LOG (GNUNET_ERROR_TYPE_ERROR,
+ _("Missing `CONFIDENCE_INTERVAL' value in configuration.\n"));
+ return NULL;
+ }
+ plugin.confidence_interval = (int) num;
api = GNUNET_new (struct GNUNET_SENSOR_ModelFunctions);
api->cls = &plugin;
- LOG(GNUNET_ERROR_TYPE_DEBUG, "Guassian model plugin is running\n");
+ api->create_model = &sensor_gaussian_model_create_model;
+ api->destroy_model = &sensor_gaussian_model_destroy_model;
+ api->feed_model = &sensor_gaussian_model_feed;
+ LOG(GNUNET_ERROR_TYPE_DEBUG, "Gaussian model plugin is running.\n");
return api;
}
@UNIXONLY@ PORT = 2087
[sensor-analysis]
-model = gaussian
\ No newline at end of file
+model = gaussian
+
+[sensor-model-gaussian]
+TRAINING_WINDOW = 1000
+CONFIDENCE_INTERVAL = 3
\ No newline at end of file