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/*
* Example plugin for NSD.
*
* Compile with something like:
*
* gcc -shared -Insd-src-dir example-plugin.c -o example-plugin.so
*
*/
#include <nsd-plugin.h>
#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
static nsd_plugin_callback_result_type reload(
const nsd_plugin_interface_type *nsd,
nsd_plugin_id_type id);
static nsd_plugin_callback_type query_received;
static nsd_plugin_callback_type query_processed;
static
void finalize(const nsd_plugin_interface_type *nsd,
nsd_plugin_id_type id ATTR_UNUSED)
{
nsd->log_msg(LOG_NOTICE, "finalizing plugin");
}
/*
* Define the plugin descriptor.
*/
static nsd_plugin_descriptor_type descriptor = {
"Example plugin",
"0.1",
finalize,
reload,
query_received,
query_processed
};
const nsd_plugin_descriptor_type *
NSD_PLUGIN_INIT(const nsd_plugin_interface_type *nsd,
nsd_plugin_id_type id,
const char *arg)
{
nsd->log_msg(LOG_NOTICE, "Example plugin initializing (arg = %s)", arg);
if (reload(nsd, id) != NSD_PLUGIN_CONTINUE) {
return NULL;
} else {
return &descriptor;
}
}
static nsd_plugin_callback_result_type
reload(const nsd_plugin_interface_type *nsd,
nsd_plugin_id_type id)
{
nsd->log_msg(LOG_NOTICE, "registering data");
if (!nsd->register_data(nsd, id,
nsd->dname_parse(nsd->nsd->db->region,
"nl",
nsd->root_dname),
"hello, world!"))
{
nsd->log_msg(LOG_ERR, "Failed to register data");
return NSD_PLUGIN_ERROR;
} else {
return NSD_PLUGIN_CONTINUE;
}
}
static nsd_plugin_callback_result_type
query_received(
const nsd_plugin_interface_type *nsd,
nsd_plugin_id_type id ATTR_UNUSED,
nsd_plugin_callback_args_type *args ATTR_UNUSED)
{
switch (fork()) {
case -1:
/* error */
nsd->log_msg(LOG_ERR, "Plugin fork failed: %s", strerror(errno));
return NSD_PLUGIN_ABANDON;
case 0:
/* child */
nsd->log_msg(LOG_NOTICE, "Plugin forked child");
exit(0);
default:
/* parent */
return NSD_PLUGIN_CONTINUE;
}
}
static nsd_plugin_callback_result_type
query_processed(
const nsd_plugin_interface_type *nsd,
nsd_plugin_id_type id ATTR_UNUSED,
nsd_plugin_callback_args_type *args)
{
nsd->log_msg(LOG_NOTICE, "domain name: %s", nsd->dname_to_string(args->query->name));
if (args->data) {
nsd->log_msg(LOG_NOTICE, "Received query with plugin data %s",
(char *) args->data);
args->result_code = RCODE_FORMAT;
return NSD_PLUGIN_ERROR;
} else {
nsd->log_msg(LOG_NOTICE, "Received query without plugin data");
return NSD_PLUGIN_CONTINUE;
}
}
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