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/* packet-lpd.c
* Routines for LPR and LPRng packet disassembly
* Gilbert Ramirez <gram@alumni.rice.edu>
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program 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 2
* of the License, or (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <epan/packet.h>
void proto_register_lpd(void);
void proto_reg_handoff_lpd(void);
#define TCP_PORT_PRINTER 515
static int proto_lpd = -1;
static int hf_lpd_response = -1;
static int hf_lpd_request = -1;
static int hf_lpd_client_code = -1;
static int hf_lpd_printer_option = -1;
static int hf_lpd_response_code = -1;
static gint ett_lpd = -1;
enum lpr_type { request, response, unknown };
static gint find_printer_string(tvbuff_t *tvb, int offset);
/* This information comes from the LPRng HOWTO, which also describes
RFC 1179. http://www.astart.com/lprng/LPRng-HOWTO.html */
static const value_string lpd_client_code[] = {
{ 1, "LPC: start print / jobcmd: abort" },
{ 2, "LPR: transfer a printer job / jobcmd: receive control file" },
{ 3, "LPQ: print short form of queue status / jobcmd: receive data file" },
{ 4, "LPQ: print long form of queue status" },
{ 5, "LPRM: remove jobs" },
{ 6, "LPRng lpc: do control operation" },
{ 7, "LPRng lpr: transfer a block format print job" },
{ 8, "LPRng lpc: secure command transfer" },
{ 9, "LPRng lpq: verbose status information" },
{ 0, NULL }
};
static const value_string lpd_server_code[] = {
{ 0, "Success: accepted, proceed" },
{ 1, "Queue not accepting jobs" },
{ 2, "Queue temporarily full, retry later" },
{ 3, "Bad job format, do not retry" },
{ 0, NULL }
};
static int
dissect_lpd(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
{
proto_tree *lpd_tree;
proto_item *ti, *hidden_item;
enum lpr_type lpr_packet_type;
guint8 code;
gint printer_len;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "LPD");
col_clear(pinfo->cinfo, COL_INFO);
/* rfc1179 states that all responses are 1 byte long */
code = tvb_get_guint8(tvb, 0);
if (tvb_reported_length(tvb) == 1) {
lpr_packet_type = response;
}
else if (code <= 9) {
lpr_packet_type = request;
}
else {
lpr_packet_type = unknown;
}
if (lpr_packet_type == request && code !=0) {
col_add_str(pinfo->cinfo, COL_INFO, val_to_str(code, lpd_client_code, "Unknown client code: %u"));
}
else if (lpr_packet_type == response) {
col_set_str(pinfo->cinfo, COL_INFO, "LPD response");
}
else {
col_set_str(pinfo->cinfo, COL_INFO, "LPD continuation");
}
ti = proto_tree_add_item(tree, proto_lpd, tvb, 0, -1, ENC_NA);
lpd_tree = proto_item_add_subtree(ti, ett_lpd);
if (lpr_packet_type == response) {
hidden_item = proto_tree_add_boolean(lpd_tree, hf_lpd_response,
tvb, 0, 0, TRUE);
} else {
hidden_item = proto_tree_add_boolean(lpd_tree, hf_lpd_request,
tvb, 0, 0, TRUE);
}
PROTO_ITEM_SET_HIDDEN(hidden_item);
if (lpr_packet_type == request) {
printer_len = find_printer_string(tvb, 1);
if (code <= 9 && printer_len != -1) {
proto_tree_add_uint_format(lpd_tree, hf_lpd_client_code, tvb, 0, 1, code,
"%s", val_to_str(code, lpd_client_code, "Unknown client code: %u"));
proto_tree_add_item(lpd_tree, hf_lpd_printer_option, tvb, 1, printer_len, ENC_ASCII|ENC_NA);
}
else {
call_data_dissector(tvb, pinfo, lpd_tree);
}
}
else if (lpr_packet_type == response) {
if (code <= 3) {
proto_tree_add_item(lpd_tree, hf_lpd_response_code, tvb, 0, 1, ENC_BIG_ENDIAN);
}
else {
call_data_dissector(tvb, pinfo, lpd_tree);
}
}
else {
call_data_dissector(tvb, pinfo, lpd_tree);
}
return tvb_captured_length(tvb);
}
static gint
find_printer_string(tvbuff_t *tvb, int offset)
{
int i;
/* try to find end of string, either '\n' or '\0' */
i = tvb_find_guint8(tvb, offset, -1, '\0');
if (i == -1)
i = tvb_find_guint8(tvb, offset, -1, '\n');
if (i == -1)
return -1;
return i - offset; /* length of string */
}
void
proto_register_lpd(void)
{
static hf_register_info hf[] = {
{ &hf_lpd_response,
{ "Response", "lpd.response",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
"TRUE if LPD response", HFILL }},
{ &hf_lpd_request,
{ "Request", "lpd.request",
FT_BOOLEAN, BASE_NONE, NULL, 0x0,
"TRUE if LPD request", HFILL }},
{ &hf_lpd_client_code,
{ "Client code", "lpd.client_code",
FT_UINT8, BASE_DEC, VALS(lpd_client_code), 0x0,
NULL, HFILL }},
{ &hf_lpd_printer_option,
{ "Printer/options", "lpd.printer_option",
FT_STRING, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
{ &hf_lpd_response_code,
{ "Response", "lpd.response_code",
FT_UINT8, BASE_DEC, VALS(lpd_server_code), 0x0,
NULL, HFILL }},
};
static gint *ett[] = {
&ett_lpd,
};
proto_lpd = proto_register_protocol("Line Printer Daemon Protocol", "LPD", "lpd");
proto_register_field_array(proto_lpd, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_lpd(void)
{
dissector_handle_t lpd_handle;
lpd_handle = create_dissector_handle(dissect_lpd, proto_lpd);
dissector_add_uint("tcp.port", TCP_PORT_PRINTER, lpd_handle);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/
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