src/tcpedit/plugins/dlt_template/plugin.c.tmpl
/* $Id$ */
/*
* Copyright (c) 2006-2007 Aaron Turner.
* Copyright (c) 2013-2014 Fred Klassen <tcpreplay at appneta dot com> - AppNeta
* 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 names of the copyright owners 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 ``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 AUTHORS OR COPYRIGHT HOLDERS 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 "defines.h"
#include "common.h"
#include "dlt_utils.h"
#include "tcpedit.h"
#include "tcpedit_stub.h"
#include "tcpr.h"
#include <stdlib.h>
#include <string.h>
#include "%{plugin}.h"
#include "%{plugin}_types.h"
/* FIXME: edit these variables to taste */
static char dlt_name[] = "%{plugin}";
static char dlt_prefix[] = "???";
static u_int16_t dlt_value = 0xFFFF;
/*
* Function to register ourselves. This function is always called, regardless
* of what DLT types are being used, so it shouldn't be allocating extra buffers
* or anything like that (use the dlt_%{plugin}_init() function below for that).
* Tasks:
* - Create a new plugin struct
* - Fill out the provides/requires bit masks. Note: Only specify which fields are
* actually in the header.
* - Add the plugin to the context's plugin chain
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int dlt_ % {plugin} _register(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
assert(ctx);
/* create a new plugin structure */
plugin = tcpedit_dlt_newplugin();
/* FIXME: set what we provide & require
plugin->provides += PLUGIN_MASK_PROTO + PLUGIN_MASK_SRCADDR + PLUGIN_MASK_DSTADDR;
plugin->requires += PLUGIN_MASK_PROTO + PLUGIN_MASK_SRCADDR + PLUGIN_MASK_DSTADDR;
*/
/* what is our DLT value? */
plugin->dlt = dlt_value;
/* set the prefix name of our plugin. This is also used as the prefix for our options */
plugin->name = safe_strdup(dlt_name);
/*
* Point to our functions, note, you need a function for EVERY method.
* Even if it is only an empty stub returning success.
*/
plugin->plugin_init = dlt_ % {plugin} _init;
plugin->plugin_post_init = dlt_ % {plugin} _init;
plugin->plugin_cleanup = dlt_ % {plugin} _cleanup;
plugin->plugin_parse_opts = dlt_ % {plugin} _parse_opts;
plugin->plugin_decode = dlt_ % {plugin} _decode;
plugin->plugin_encode = dlt_ % {plugin} _encode;
plugin->plugin_proto = dlt_ % {plugin} _proto;
plugin->plugin_l2addr_type = dlt_ % {plugin} _l2addr_type;
plugin->plugin_l2len = dlt_ % {plugin} _l2len;
plugin->plugin_get_layer3 = dlt_ % {plugin} _get_layer3;
plugin->plugin_merge_layer3 = dlt_ % {plugin} _merge_layer3;
plugin->plugin_get_mac = dlt_ % {plugin} _get_mac;
/* add it to the available plugin list */
return tcpedit_dlt_addplugin(ctx, plugin);
}
/*
* Initializer function. This function is called only once, if and only if
* this plugin will be utilized. Remember, if you need to keep track of any state,
* store it in your plugin->config, not a global!
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int dlt_ % {plugin} _init(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
% {plugin} _config_t *config;
assert(ctx);
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt_value)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to initialize unregistered plugin %s", dlt_name);
return TCPEDIT_ERROR;
}
/* allocate memory for our deocde extra data */
if (sizeof(% {plugin} _extra_t) > 0)
ctx->decoded_extra = safe_malloc(sizeof(% {plugin} _extra_t));
/* allocate memory for our config data */
if (sizeof(% {plugin} _config_t) > 0)
plugin->config = safe_malloc(sizeof(% {plugin} _config_t));
config = (% {plugin} _config_t *)plugin->config;
/* FIXME: set default config values here */
return TCPEDIT_OK; /* success */
}
/**
* Post init function. This function is called only once after init() and parse_opts()
* It basically allows decoders to properly initialize sub-plugins.
*/
int dlt_ % {plugin} _post_init(tcpeditdlt_t *ctx)
{
/* FIXME: Only needs to do something if we're using a sub-plugin
* See the jnpr_ether_plugin for an example of this
%{plugin}_config_t *config;
// do nothing if we're not the decoder
if (ctx->decoder->dlt != dlt_value)
return TCPEDIT_OK;
// init our subcontext & decoder
config = (%{plugin}_config_t *)ctx->encoder->config;
config->subctx = tcpedit_dlt_init(ctx->tcpedit, SUB_PLUGIN_DLT_TYPE);
*/
return TCPEDIT_OK;
}
/*
* Since this is used in a library, we should manually clean up after ourselves
* Unless you allocated some memory in dlt_%{plugin}_init(), this is just an stub.
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int dlt_ % {plugin} _cleanup(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
assert(ctx);
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt_value)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to cleanup unregistered plugin %s", dlt_name);
return TCPEDIT_ERROR;
}
/* FIXME: make this function do something if necessary */
if (ctx->decoded_extra != NULL) {
safe_free(ctx->decoded_extra);
ctx->decoded_extra = NULL;
}
if (plugin->config != NULL) {
safe_free(plugin->config);
plugin->config = NULL;
}
return TCPEDIT_OK; /* success */
}
/*
* This is where you should define all your AutoGen AutoOpts option parsing.
* Any user specified option should have it's bit turned on in the 'provides'
* bit mask.
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int dlt_ % {plugin} _parse_opts(tcpeditdlt_t *ctx)
{
assert(ctx);
/* FIXME: make this function work */
return TCPEDIT_OK; /* success */
}
/*
* Function to decode the layer 2 header in the packet.
* You need to fill out:
* - ctx->l2len
* - ctx->srcaddr
* - ctx->dstaddr
* - ctx->proto
* - ctx->decoded_extra
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int dlt_ % {plugin} _decode(tcpeditdlt_t *ctx, const u_char *packet, int pktlen)
{
assert(ctx);
assert(packet);
if (pktlen > /* FIXME: our L2 length */)
return TCPEDIT_ERROR;
/* FIXME: make this function work */
return TCPEDIT_OK; /* success */
}
/*
* Function to encode the layer 2 header back into the packet.
* Returns: total packet len or TCPEDIT_ERROR
*/
int dlt_ % {plugin} _encode(tcpeditdlt_t *ctx, u_char *packet, int pktlen, _U_ tcpr_dir_t dir)
{
assert(ctx);
assert(packet);
if (pktlen < /* FIXME: our L2 length */)
return TCPEDIT_ERROR;
/* FIXME: make this function work */
return pktlen; /* success */
}
/*
* Function returns the Layer 3 protocol type of the given packet, or TCPEDIT_ERROR on error
* Make sure you return this value in NETWORK byte order!
*/
int dlt_ % {plugin} _proto(tcpeditdlt_t *ctx, const u_char *packet, int pktlen)
{
assert(ctx);
assert(packet);
int protocol;
if (pktlen > /* FIXME: our L2 length */)
return TCPEDIT_ERROR;
/* FIXME: make this function work */
return protocol;
}
/*
* Function returns a pointer to the layer 3 protocol header or NULL on error
*/
u_char *dlt_ % {plugin} _get_layer3(tcpeditdlt_t *ctx, u_char *packet, int pktlen)
{
int l2len;
assert(ctx);
assert(packet);
/* FIXME: Is there anything else we need to do?? */
l2len = dlt_ % {plugin} _l2len(ctx, packet, pktlen);
if (pktlen < l2len)
return NULL;
return tcpedit_dlt_l3data_copy(ctx, packet, pktlen, l2len);
}
/*
* function merges the packet (containing L2 and old L3) with the l3data buffer
* containing the new l3 data. Note, if L2 % 4 == 0, then they're pointing to the
* same buffer, otherwise there was a memcpy involved on strictly aligned architectures
* like SPARC
*/
u_char *dlt_ % {plugin} _merge_layer3(tcpeditdlt_t *ctx, u_char *packet, int pktlen, u_char *l3data)
{
int l2len;
assert(ctx);
assert(packet);
assert(l3data);
/* FIXME: Is there anything else we need to do?? */
l2len = dlt_ % {plugin} _l2len(ctx, packet, pktlen);
if (pktlen < l2len)
;
return NULL;
return tcpedit_dlt_l3data_merge(ctx, packet, pktlen, l3data, l2len);
}
/*
* return a static pointer to the source/destination MAC address
* return NULL on error/address doesn't exist
*/
u_char *dlt_ % {plugin} _get_mac(tcpeditdlt_t *ctx, tcpeditdlt_mac_type_t mac, const u_char *packet, int pktlen)
{
assert(ctx);
assert(packet);
if (pktlen < 14)
return NULL;
/* FIXME: return a ptr to the source or dest mac address. */
switch (mac) {
case SRC_MAC:
memcpy(ctx->srcmac, packet, length);
return (ctx->srcmac);
break;
case DST_MAC:
memcpy(ctx->dstmac, packet, length);
return (ctx->dstmac);
break;
default:
errx(-1, "Invalid tcpeditdlt_mac_type_t: %d", mac);
}
}
/*
* return the length of the L2 header of the current packet
*/
int dlt_ % {plugin} _l2len(tcpeditdlt_t *ctx, const u_char *packet, int pktlen)
{
assert(ctx);
assert(packet);
if (pktlen < 14)
return 0;
/* FIXME: return the actual length of your L2 header... parse the packet if you must */
return 14;
}
tcpeditdlt_l2addr_type_t dlt_ % {plugin} _l2addr_type(void)
{
/* FIXME: return the tcpeditdlt_l2addr_type_t value that this DLT uses */
return ETHERNET;
}