src/tcpedit/plugins/dlt_loop/loop.c
/* $Id$ */
/*
* Copyright (c) 2001-2010 Aaron Turner <aturner at synfin dot net>
* Copyright (c) 2013-2024 Fred Klassen <tcpreplay at appneta dot com> - AppNeta
*
* The Tcpreplay Suite of tools is free software: you can redistribute it
* and/or modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or with the authors permission any later version.
*
* The Tcpreplay Suite is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with the Tcpreplay Suite. If not, see <http://www.gnu.org/licenses/>.
*/
#include "loop.h"
#include "../dlt_null/null.h"
#include "dlt_utils.h"
#include "tcpedit.h"
#include "tcpedit_stub.h"
#include <string.h>
/*
* Basically, DLT_LOOP and DLT_NULL are the same thing except that the PF_ value
* in the header is always network byte order in DLT_LOOP and host byte order
* in DLT_NULL. So since DLT_NULL has to handle both big & little endian values
* we just send all DLT_LOOP processing over there
*/
static char dlt_name[] = "loop";
static char _U_ dlt_prefix[] = "loop";
static uint16_t dlt_value = DLT_LOOP;
/*
* 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_loop_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_loop_register(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
assert(ctx);
/* create a new plugin structure */
plugin = tcpedit_dlt_newplugin();
/* set what we provide & require */
plugin->provides += PLUGIN_MASK_PROTO;
plugin->
requires
+= 0;
/* 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_prefix);
/* we actually call all the DLT_NULL functions since NULL and LOOP are basically the same thing */
plugin->plugin_init = dlt_loop_init;
plugin->plugin_cleanup = dlt_loop_cleanup;
plugin->plugin_parse_opts = dlt_null_parse_opts;
plugin->plugin_decode = dlt_null_decode;
plugin->plugin_encode = dlt_null_encode;
plugin->plugin_proto = dlt_null_proto;
plugin->plugin_l2addr_type = dlt_null_l2addr_type;
plugin->plugin_l2len = dlt_null_l2len;
plugin->plugin_get_layer3 = dlt_null_get_layer3;
plugin->plugin_merge_layer3 = dlt_null_merge_layer3;
plugin->plugin_get_mac = dlt_null_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_loop_init(tcpeditdlt_t *ctx)
{
assert(ctx);
if (tcpedit_dlt_getplugin(ctx, dlt_value) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to initialize unregistered plugin %s", dlt_name);
return TCPEDIT_ERROR;
}
return TCPEDIT_OK; /* success */
}
/*
* Since this is used in a library, we should manually clean up after ourselves
* Unless you allocated some memory in dlt_loop_init(), this is just an stub.
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int
dlt_loop_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;
}
safe_free(plugin->name);
plugin->name = NULL;
safe_free(plugin->config);
plugin->config = NULL;
plugin->config_size = 0;
return TCPEDIT_OK; /* success */
}
/* that's all folks! */