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/*
* Copyright (c) 2016-2025 OARC, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <netinet/in.h>
#include "dnscap_common.h"
static logerr_t* logerr;
static int opt_f = 0;
static const char* opt_x = 0;
output_t template_output;
void template_usage()
{
fprintf(stderr,
"\ntemplate.so options:\n"
"\t-? print these instructions and exit\n"
"\t-f flag option\n"
"\t-x <arg> option with argument\n");
}
void template_getopt(int* argc, char** argv[])
{
/*
* The "getopt" function will be called from the parent to
* process plugin options.
*/
int c;
while ((c = getopt(*argc, *argv, "?fx:")) != EOF) {
switch (c) {
case 'f':
opt_f = 1;
break;
case 'x':
opt_x = strdup(optarg);
break;
case '?':
template_usage();
if (!optopt || optopt == '?') {
exit(0);
}
// fallthrough
default:
exit(1);
}
}
}
int template_start(logerr_t* a_logerr)
{
/*
* The "start" function is called once, when the program
* starts. It is used to initialize the plugin. If the
* plugin wants to write debugging and or error messages,
* it should save the a_logerr pointer passed from the
* parent code.
*/
logerr = a_logerr;
return 0;
}
void template_stop()
{
/*
* The "start" function is called once, when the program
* is exiting normally. It might be used to clean up state,
* free memory, etc.
*/
}
int template_open(my_bpftimeval ts)
{
/*
* The "open" function is called at the start of each
* collection interval, which might be based on a period
* of time or a number of packets. In the original code,
* this is where we opened an output pcap file.
*/
return 0;
}
int template_close(my_bpftimeval ts)
{
/*
* The "close" function is called at the end of each
* collection interval, which might be based on a period
* of time or on a number of packets. In the original code
* this is where we closed an output pcap file.
*/
return 0;
}
void template_output(const char* descr, iaddr from, iaddr to, uint8_t proto, unsigned flags,
unsigned sport, unsigned dport, my_bpftimeval ts,
const u_char* pkt_copy, const unsigned olen,
const u_char* payload, const unsigned payloadlen)
{
/*
* Here you can "process" a packet. The function is named
* "output" because in the original code this is where
* packets were outputted.
*
* if flags & PCAP_OUTPUT_ISDNS != 0 then payload is the start of a DNS message.
*
* if flags & PCAP_OUTPUT_ISFRAG != 0 then the packet is a fragment.
*
* if flags & PCAP_OUTPUT_ISLAYER != 0 then the pkt_copy is the same as payload.
*/
}
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