Squelch an MSVC++ complaint.
[obnox/wireshark/wip.git] / packet-lpd.c
1 /* packet-lpd.c
2  * Routines for LPR and LPRng packet disassembly
3  * Gilbert Ramirez <gram@xiexie.org>
4  *
5  * $Id: packet-lpd.c,v 1.28 2001/06/18 02:17:48 guy Exp $
6  *
7  * Ethereal - Network traffic analyzer
8  * By Gerald Combs <gerald@zing.org>
9  * Copyright 1998 Gerald Combs
10  *
11  * 
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * as published by the Free Software Foundation; either version 2
15  * of the License, or (at your option) any later version.
16  * 
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  * 
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
25  */
26
27 #ifdef HAVE_CONFIG_H
28 # include "config.h"
29 #endif
30
31 #ifdef HAVE_SYS_TYPES_H
32 # include <sys/types.h>
33 #endif
34
35 #include <string.h>
36
37 #include <glib.h>
38 #include "packet.h"
39
40 #define TCP_PORT_PRINTER                515
41
42 static int proto_lpd = -1;
43 static int hf_lpd_response = -1;
44 static int hf_lpd_request = -1;
45
46 static gint ett_lpd = -1;
47
48 enum lpr_type { request, response, unknown };
49
50 static gint find_printer_string(tvbuff_t *tvb, int offset);
51
52 static void
53 dissect_lpd(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
54 {
55         proto_tree      *lpd_tree;
56         proto_item      *ti;
57         enum lpr_type   lpr_packet_type;
58         guint8          code;
59         gint            printer_len;
60
61         /* This information comes from the LPRng HOWTO, which also describes
62                 RFC 1179. http://www.astart.com/lprng/LPRng-HOWTO.html */
63         char            *lpd_client_code[] = {
64                 "Unknown command",
65                 "LPC: start print / jobcmd: abort",
66                 "LPR: transfer a printer job / jobcmd: receive control file",
67                 "LPQ: print short form of queue status / jobcmd: receive data file",
68                 "LPQ: print long form of queue status",
69                 "LPRM: remove jobs",
70                 "LPRng lpc: do control operation",
71                 "LPRng lpr: transfer a block format print job",
72                 "LPRng lpc: secure command transfer",
73                 "LPRng lpq: verbose status information"
74         };
75         char            *lpd_server_code[] = {
76                 "Success: accepted, proceed",
77                 "Queue not accepting jobs",
78                 "Queue temporarily full, retry later",
79                 "Bad job format, do not retry"
80         };
81
82         if (check_col(pinfo->fd, COL_PROTOCOL))
83                 col_set_str(pinfo->fd, COL_PROTOCOL, "LPD");
84         if (check_col(pinfo->fd, COL_INFO))
85                 col_clear(pinfo->fd, COL_INFO);
86
87         /* rfc1179 states that all responses are 1 byte long */
88         code = tvb_get_guint8(tvb, 0);
89         if (tvb_reported_length(tvb) == 1) {
90                 lpr_packet_type = response;
91         }
92         else if (code <= 9) {
93                 lpr_packet_type = request;
94         }
95         else {
96                 lpr_packet_type = unknown;
97         }
98
99         if (check_col(pinfo->fd, COL_INFO)) {
100                 if (lpr_packet_type == request) {
101                         col_add_str(pinfo->fd, COL_INFO, lpd_client_code[code]);
102                 }
103                 else if (lpr_packet_type == response) {
104                         col_set_str(pinfo->fd, COL_INFO, "LPD response");
105                 }
106                 else {
107                         col_set_str(pinfo->fd, COL_INFO, "LPD continuation");
108                 }
109         }
110
111         if (tree) {
112                 ti = proto_tree_add_item(tree, proto_lpd, tvb, 0, 
113                                          tvb_length(tvb), FALSE);
114                 lpd_tree = proto_item_add_subtree(ti, ett_lpd);
115
116                 if (lpr_packet_type == response) {
117                   proto_tree_add_boolean_hidden(lpd_tree, hf_lpd_response,
118                                                 tvb, 0, 0, TRUE);
119                 } else {
120                   proto_tree_add_boolean_hidden(lpd_tree, hf_lpd_request,
121                                                 tvb, 0, 0, TRUE);
122                 }
123
124                 if (lpr_packet_type == request) {
125                         printer_len = find_printer_string(tvb, 1);
126
127                         if (code <= 9 && printer_len != -1) {
128                                 proto_tree_add_text(lpd_tree, tvb, 0, 1,
129                                         lpd_client_code[code]);
130                                 proto_tree_add_text(lpd_tree, tvb, 1, printer_len,
131                                          "Printer/options: %s",
132                                          tvb_format_text(tvb, 1, printer_len));
133                         }
134                         else {
135                                 dissect_data(tvb, 0, pinfo, tree);
136                         }
137                 }
138                 else if (lpr_packet_type == response) {
139                         if (code <= 3) {
140                                 proto_tree_add_text(lpd_tree, tvb, 0, 1,
141                                         "Response: %s", lpd_server_code[code]);
142                         }
143                         else {
144                                 dissect_data(tvb, 0, pinfo, tree);
145                         }
146                 }
147                 else {
148                         dissect_data(tvb, 0, pinfo, tree);
149                 }
150         }
151 }
152
153
154 static gint
155 find_printer_string(tvbuff_t *tvb, int offset)
156 {
157         int     i;
158
159         /* try to find end of string, either '\n' or '\0' */
160         i = tvb_find_guint8(tvb, offset, -1, '\0');
161         if (i == -1)
162                 i = tvb_find_guint8(tvb, offset, -1, '\n');
163         if (i == -1)
164                 return -1;
165         return i - offset;      /* length of string */
166 }
167
168
169 void
170 proto_register_lpd(void)
171 {
172   static hf_register_info hf[] = {
173     { &hf_lpd_response,
174       { "Response",           "lpd.response",           
175         FT_BOOLEAN, BASE_NONE, NULL, 0x0,
176         "TRUE if LPD response", HFILL }},
177
178     { &hf_lpd_request,
179       { "Request",            "lpd.request",
180         FT_BOOLEAN, BASE_NONE, NULL, 0x0,
181         "TRUE if LPD request", HFILL }}
182   };
183   static gint *ett[] = {
184     &ett_lpd,
185   };
186
187   proto_lpd = proto_register_protocol("Line Printer Daemon Protocol", "LPD", "lpd");
188   proto_register_field_array(proto_lpd, hf, array_length(hf));
189   proto_register_subtree_array(ett, array_length(ett));
190 }
191
192 void
193 proto_reg_handoff_lpd(void)
194 {
195   dissector_add("tcp.port", TCP_PORT_PRINTER, &dissect_lpd, proto_lpd);
196 }