/*
* Initializer function. This function is called only once, if and only iif
* 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_hdlc_init(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
hdlc_config_t *config;
assert(ctx);
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt_value)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to initalize unregistered plugin %s", dlt_name);
return TCPEDIT_ERROR;
}
/* allocate memory for our deocde extra data */
if (sizeof(hdlc_extra_t) > 0)
ctx->decoded_extra = safe_malloc(sizeof(hdlc_extra_t));
/* allocate memory for our config data */
if (sizeof(hdlc_config_t) > 0)
plugin->config = safe_malloc(sizeof(hdlc_config_t));
config = (hdlc_config_t *)plugin->config;
/* default to unset */
config->address = 65535;
config->control = 65535;
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_jnpr_ether_init(), this is just an stub.
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int
dlt_jnpr_ether_cleanup(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
jnpr_ether_config_t *config;
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;
}
if (ctx->decoded_extra != NULL) {
safe_free(ctx->decoded_extra);
ctx->decoded_extra = NULL;
}
if (plugin->config != NULL) {
/* clean up the en10mb plugin */
config = (jnpr_ether_config_t *)ctx->encoder->config;
tcpedit_dlt_cleanup(config->subctx);
plugin->config = NULL;
}
return TCPEDIT_OK; /* success */
}
/*
* Initializer function. This function is called only once, if and only iif
* 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_radiotap_init(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
radiotap_config_t *config;
assert(ctx);
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt_value)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to initalize unregistered plugin %s", dlt_name);
return TCPEDIT_ERROR;
}
/* allocate memory for our deocde extra data */
if (sizeof(radiotap_extra_t) > 0)
ctx->decoded_extra = safe_malloc(sizeof(radiotap_extra_t));
/* allocate memory for our config data */
if (sizeof(radiotap_config_t) > 0)
plugin->config = safe_malloc(sizeof(radiotap_config_t));
config = (radiotap_config_t *)plugin->config;
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_null_init(), this is just an stub.
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int
dlt_null_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;
}
if (ctx->decoded_extra != NULL) {
safe_free(ctx->decoded_extra);
ctx->decoded_extra = NULL;
ctx->decoded_extra_size = 0;
}
if (plugin->config != NULL) {
safe_free(plugin->config);
plugin->config = NULL;
plugin->config_size = 0;
}
return TCPEDIT_OK; /* success */
}
/**
* Set output DLT plugin by using it's DLT_<type>. Note that the user plugin
* is DLT_USER0.
*/
int
tcpedit_set_encoder_dltplugin_byid(tcpedit_t *tcpedit, int dlt)
{
tcpeditdlt_plugin_t *plugin;
tcpeditdlt_t *ctx;
assert(tcpedit);
ctx = tcpedit->dlt_ctx;
assert(ctx);
if (ctx->encoder) {
tcpedit_seterr(tcpedit, "You have already selected a DLT encoder: %s", ctx->encoder->name);
return TCPEDIT_ERROR;
}
plugin = tcpedit_dlt_getplugin(ctx, dlt);
if (plugin == NULL) {
tcpedit_seterr(tcpedit, "No output DLT plugin decoder with DLT type: 0x%04x", dlt);
return TCPEDIT_ERROR;
}
ctx->encoder = plugin;
/* init the encoder plugin if it's not the decoder plugin too */
if (ctx->encoder->dlt != ctx->decoder->dlt) {
if (ctx->encoder->plugin_init(ctx) != TCPEDIT_OK) {
/* plugin should generate the error */
return TCPEDIT_ERROR;
}
}
return TCPEDIT_OK;
}
/*
* Function to encode the layer 2 header back into the packet.
* Returns: total packet len or TCPEDIT_ERROR
*/
int
dlt_hdlc_encode(tcpeditdlt_t *ctx, u_char *packet, int pktlen, _U_ tcpr_dir_t dir)
{
cisco_hdlc_t *hdlc;
hdlc_config_t *config = NULL;
hdlc_extra_t *extra = NULL;
tcpeditdlt_plugin_t *plugin = NULL;
u_char tmpbuff[MAXPACKET];
int newpktlen;
assert(ctx);
assert(pktlen >= 4);
assert(packet);
/* Make room for our new l2 header if old l2len != 4 */
if (ctx->l2len > 4) {
memmove(packet + 4, packet + ctx->l2len, pktlen - ctx->l2len);
} else if (ctx->l2len < 4) {
memcpy(tmpbuff, packet, pktlen);
memcpy(packet + 4, (tmpbuff + ctx->l2len), pktlen - ctx->l2len);
}
/* update the total packet length */
newpktlen = pktlen + 4 - ctx->l2len;
/*
* HDLC doesn't support direction, since we have no real src/dst addresses
* to deal with, so we just use the original packet data or option data
*/
hdlc = (cisco_hdlc_t *)packet;
plugin = tcpedit_dlt_getplugin(ctx, dlt_value);
config = plugin->config;
extra = (hdlc_extra_t *)ctx->decoded_extra;
/* set the address field */
if (config->address < 65535) {
hdlc->address = (uint8_t)config->address;
} else if (extra->hdlc) {
hdlc->address = extra->hdlc;
} else {
tcpedit_seterr(ctx->tcpedit, "%s", "Non-HDLC packet requires --hdlc-address");
return TCPEDIT_ERROR;
}
/* set the control field */
if (config->control < 65535) {
hdlc->control = (uint8_t)config->control;
} else if (extra->hdlc) {
hdlc->control = extra->hdlc;
} else {
tcpedit_seterr(ctx->tcpedit, "%s", "Non-HDLC packet requires --hdlc-control");
return TCPEDIT_ERROR;
}
/* copy over our protocol */
hdlc->protocol = ctx->proto;
return newpktlen; /* success */
}
uint16_t
dlt_user_get_output_dlt(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
user_config_t *config;
assert(ctx);
plugin = tcpedit_dlt_getplugin(ctx, dlt_value);
config = plugin->config;
return config->dlt;
}
/*
* 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)
{
tcpeditdlt_plugin_t *plugin;
assert(ctx);
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt_value)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to initalize unregistered plugin %s", dlt_name);
return TCPEDIT_ERROR;
}
return TCPEDIT_OK; /* success */
}
/*
* return the length of the L2 header of the current packet
*/
int
dlt_user_l2len(tcpeditdlt_t *ctx, const u_char *packet, const int pktlen)
{
tcpeditdlt_plugin_t *plugin;
user_config_t *config;
assert(ctx);
assert(packet);
assert(pktlen);
plugin = tcpedit_dlt_getplugin(ctx, dlt_value);
config = plugin->config;
return config->length;
}
/**
* initialize our plugin library. Pass the DLT of the source pcap handle.
* Actions:
* - Create new tcpeditdlt_t context
* - Link tcpedit to new context
* - Register plugins
* - Select decoder plugin using srcdlt
* - Select encoder plugin using destination name
* - Initialize decoder/encoder plugins
* - Parse options for encoder plugin
* - Validate provides/reqiures + user options
*/
tcpeditdlt_t *
tcpedit_dlt_init(tcpedit_t *tcpedit, const int srcdlt)
{
tcpeditdlt_t *ctx;
int rcode;
assert(tcpedit);
assert(srcdlt >= 0);
ctx = (tcpeditdlt_t *)safe_malloc(sizeof(tcpeditdlt_t));
/* do we need a side buffer for L3 data? */
#ifdef FORCE_ALIGN
ctx->l3buff = (u_char *)safe_malloc(MAXPACKET);
#endif
/* copy our tcpedit context */
ctx->tcpedit = tcpedit;
/* register all our plugins */
if (tcpedit_dlt_register(ctx) != TCPEDIT_OK) {
tcpedit_dlt_cleanup(ctx);
return NULL;
}
/* Choose decode plugin */
if ((ctx->decoder = tcpedit_dlt_getplugin(ctx, srcdlt)) == NULL) {
tcpedit_seterr(tcpedit, "No DLT plugin available for source DLT: 0x%x", srcdlt);
tcpedit_dlt_cleanup(ctx);
return NULL;
}
/* set our dlt type */
ctx->dlt = srcdlt;
/* set our address type */
ctx->addr_type = ctx->decoder->plugin_l2addr_type();
/* initalize decoder plugin */
rcode = ctx->decoder->plugin_init(ctx);
if (tcpedit_checkerror(ctx->tcpedit, rcode, NULL) != TCPEDIT_OK) {
tcpedit_dlt_cleanup(ctx);
return NULL;
}
/* we're OK */
return ctx;
}
/**
* Get the layer 2 length of the packet using the DLT plugin currently in
* place
*/
int
tcpedit_dlt_l2len(tcpeditdlt_t *ctx, int dlt, const u_char *packet, const int pktlen)
{
tcpeditdlt_plugin_t *plugin;
assert(ctx);
assert(dlt >= 0);
assert(packet);
assert(pktlen);
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to find plugin for DLT 0x%04x", dlt);
return -1;
}
return plugin->plugin_l2len(ctx, packet, pktlen);
}
/*
* 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_user_parse_opts(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
user_config_t *config;
assert(ctx);
plugin = tcpedit_dlt_getplugin(ctx, dlt_value);
config = plugin->config;
/*
* --user-dlt will override the output DLT type, otherwise we'll use
* the DLT of the decoder
*/
if (HAVE_OPT(USER_DLT)) {
config->dlt = OPT_VALUE_USER_DLT;
} else {
config->dlt = ctx->decoder->dlt;
}
/* --user-dlink */
if (HAVE_OPT(USER_DLINK)) {
int ct = STACKCT_OPT(USER_DLINK);
char **list = STACKLST_OPT(USER_DLINK);
int first = 1;
do {
char *p = *list++;
if (first) {
config->length = read_hexstring(p, config->l2server, USER_L2MAXLEN);
memcpy(config->l2client, config->l2server, config->length);
} else {
if (config->length != read_hexstring(p, config->l2client, USER_L2MAXLEN)) {
tcpedit_seterr(ctx->tcpedit, "%s",
"both --dlink's must contain the same number of bytes");
return TCPEDIT_ERROR;
}
}
first = 0;
} while (--ct > 0);
}
return TCPEDIT_OK; /* success */
}
/**
* \brief Merge the Layer 3 data back onto the mainbuffer so it's immediately
* after the layer 2 header
*
* Since some L2 headers aren't strictly aligned, we need to "merge" the packet w/ L2 data
* and the L3 buffer. This is basically a NO-OP for things like vlan tagged ethernet (16 byte) header
* or Cisco HDLC (4 byte header) but is critical for std ethernet (12 byte header)
*/
u_char *
tcpedit_dlt_merge_l3data(tcpeditdlt_t *ctx, int dlt, u_char *packet, const int pktlen, u_char *l3data)
{
tcpeditdlt_plugin_t *plugin;
assert(ctx);
assert(dlt >= 0);
assert(pktlen >= 0);
assert(packet);
if (l3data == NULL)
return packet;
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to find plugin for DLT 0x%04x", dlt);
return NULL;
}
return plugin->plugin_merge_layer3(ctx, packet, pktlen, l3data);
}
/*
* 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_hdlc_parse_opts(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
hdlc_config_t *config;
assert(ctx);
plugin = tcpedit_dlt_getplugin(ctx, dlt_value);
config = plugin->config;
if (HAVE_OPT(HDLC_CONTROL)) {
config->control = (uint16_t)OPT_VALUE_HDLC_CONTROL;
}
if (HAVE_OPT(HDLC_ADDRESS)) {
config->address = (uint16_t)OPT_VALUE_HDLC_ADDRESS;
}
return TCPEDIT_OK; /* success */
}
/*
* 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_linuxsll_init(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
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 decode extra data */
ctx->decoded_extra_size = sizeof(linuxsll_extra_t);
ctx->decoded_extra = safe_malloc(ctx->decoded_extra_size);
/* allocate memory for our config data */
plugin->config_size = sizeof(linuxsll_config_t);
plugin->config = safe_malloc(plugin->config_size);
return TCPEDIT_OK; /* success */
}
/*
* Initializer function. This function is called only once, if and only iif
* 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_ieee80211_init(tcpeditdlt_t *ctx)
{
tcpeditdlt_plugin_t *plugin;
assert(ctx);
if ((plugin = tcpedit_dlt_getplugin(ctx, dlt_value)) == NULL) {
tcpedit_seterr(ctx->tcpedit, "Unable to initalize unregistered plugin %s", dlt_name);
return TCPEDIT_ERROR;
}
/* allocate memory for our deocde extra data */
if (sizeof(ieee80211_extra_t) > 0)
ctx->decoded_extra = safe_malloc(sizeof(ieee80211_extra_t));
/* allocate memory for our config data */
if (sizeof(ieee80211_config_t) > 0)
plugin->config = safe_malloc(sizeof(ieee80211_config_t));
/* FIXME: set default config values here */
return TCPEDIT_OK; /* success */
}
/*
* Function to encode the layer 2 header back into the packet.
* Returns: total packet len or TCPEDIT_ERROR
*/
int
dlt_user_encode(tcpeditdlt_t *ctx, u_char *packet, int pktlen, tcpr_dir_t dir)
{
user_config_t *config;
tcpeditdlt_plugin_t *plugin;
u_char tmpbuff[MAXPACKET];
assert(ctx);
assert(pktlen > 0);
assert(packet);
plugin = tcpedit_dlt_getplugin(ctx, dlt_value);
config = plugin->config;
/* Make room for our new l2 header if l2len != config->length */
if (ctx->l2len > config->length) {
memmove(packet + config->length, packet + ctx->l2len, pktlen - ctx->l2len);
} else if (ctx->l2len < config->length) {
memcpy(tmpbuff, packet, pktlen);
memcpy(packet + config->length, (tmpbuff + ctx->l2len), pktlen - ctx->l2len);
}
/* update the total packet length */
pktlen += config->length - ctx->l2len;
if (dir == TCPR_DIR_C2S) {
memcpy(packet, config->l2client, config->length);
} else if (dir == TCPR_DIR_S2C) {
memcpy(packet, config->l2server, config->length);
} else {
tcpedit_seterr(ctx->tcpedit, "%s", "Encoders only support C2S or C2S!");
return TCPEDIT_ERROR;
}
return pktlen; /* success */
}
/*
* Since this is used in a library, we should manually clean up after ourselves
* Unless you allocated some memory in dlt_user_init(), this is just an stub.
* Returns: TCPEDIT_ERROR | TCPEDIT_OK | TCPEDIT_WARN
*/
int
dlt_user_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 */
}
