/* packet-cups.c
* Routines for Common Unix Printing System (CUPS) Browsing Protocol
* packet disassembly for the Wireshark network traffic analyzer.
*
* Charles Levert <charles@comm.polymtl.ca>
* Copyright 2001 Charles Levert
*
* $Id: packet-cups.c 35158 2010-12-08 20:14:57Z etxrab $
*
* 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>
#include <ctype.h>

#include <glib.h>
#include <epan/packet.h>
#include <epan/strutil.h>

/**********************************************************************/

/* From cups/cups.h, GNU GPL, Copyright 1997-2001 by Easy Software Products. */
typedef guint32 cups_ptype_t;           /**** Printer Type/Capability Bits ****/
enum                                    /* Not a typedef'd enum so we can OR */
{
  CUPS_PRINTER_LOCAL = 0x0000,          /* Local printer or class */
  CUPS_PRINTER_CLASS = 0x0001,          /* Printer class */
  CUPS_PRINTER_REMOTE = 0x0002,         /* Remote printer or class */
  CUPS_PRINTER_BW = 0x0004,             /* Can do B&W printing */
  CUPS_PRINTER_COLOR = 0x0008,          /* Can do color printing */
  CUPS_PRINTER_DUPLEX = 0x0010,         /* Can do duplexing */
  CUPS_PRINTER_STAPLE = 0x0020,         /* Can staple output */
  CUPS_PRINTER_COPIES = 0x0040,         /* Can do copies */
  CUPS_PRINTER_COLLATE = 0x0080,        /* Can collage copies */
  CUPS_PRINTER_PUNCH = 0x0100,          /* Can punch output */
  CUPS_PRINTER_COVER = 0x0200,          /* Can cover output */
  CUPS_PRINTER_BIND = 0x0400,           /* Can bind output */
  CUPS_PRINTER_SORT = 0x0800,           /* Can sort output */
  CUPS_PRINTER_SMALL = 0x1000,          /* Can do Letter/Legal/A4 */
  CUPS_PRINTER_MEDIUM = 0x2000,         /* Can do Tabloid/B/C/A3/A2 */
  CUPS_PRINTER_LARGE = 0x4000,          /* Can do D/E/A1/A0 */
  CUPS_PRINTER_VARIABLE = 0x8000,       /* Can do variable sizes */
  CUPS_PRINTER_IMPLICIT = 0x10000,      /* Implicit class */
  CUPS_PRINTER_DEFAULT = 0x20000,       /* Default printer on network */
  CUPS_PRINTER_OPTIONS = 0xfffc         /* ~(CLASS | REMOTE | IMPLICIT) */
};
/* End insert from cups/cups.h */

typedef struct {
	guint32	bit;
	const char	*on_string;
	const char	*off_string;
} cups_ptype_bit_info;

static const cups_ptype_bit_info cups_ptype_bits[] = {
	{ CUPS_PRINTER_DEFAULT,
	  "Default printer on network", "Not default printer" },
	{ CUPS_PRINTER_IMPLICIT,
	  "Implicit class", "Explicit class" },
	{ CUPS_PRINTER_VARIABLE,
	  "Can print variable sizes", "Cannot print variable sizes" },
	{ CUPS_PRINTER_LARGE,
	  "Can print up to 36x48 inches", "Cannot print up to 36x48 inches" },
	{ CUPS_PRINTER_MEDIUM,
	  "Can print up to 18x24 inches", "Cannot print up to 18x24 inches" },
	{ CUPS_PRINTER_SMALL,
	  "Can print up to 9x14 inches", "Cannot print up to 9x14 inches" },
	{ CUPS_PRINTER_SORT,
	  "Can sort", "Cannot sort" },
	{ CUPS_PRINTER_BIND,
	  "Can bind", "Cannot bind" },
	{ CUPS_PRINTER_COVER,
	  "Can cover", "Cannot cover" },
	{ CUPS_PRINTER_PUNCH,
	  "Can punch holes", "Cannot punch holes" },
	{ CUPS_PRINTER_COLLATE,
	  "Can do fast collating", "Cannot do fast collating" },
	{ CUPS_PRINTER_COPIES,
	  "Can do fast copies", "Cannot do fast copies" },
	{ CUPS_PRINTER_STAPLE,
	  "Can staple", "Cannot staple" },
	{ CUPS_PRINTER_DUPLEX,
	  "Can duplex", "Cannot duplex" },
	{ CUPS_PRINTER_COLOR,
	  "Can print color", "Cannot print color" },
	{ CUPS_PRINTER_BW,
	  "Can print black", "Cannot print black" },
	{ CUPS_PRINTER_REMOTE,
	  "Remote", "Local (illegal)" },
	{ CUPS_PRINTER_CLASS,
	  "Printer class", "Single printer" }
};

#define N_CUPS_PTYPE_BITS	(sizeof cups_ptype_bits / sizeof cups_ptype_bits[0])

typedef enum _cups_state {
	CUPS_IDLE = 3,
	CUPS_PROCESSING,
	CUPS_STOPPED
} cups_state_t;

static const value_string cups_state_values[] = {
	{ CUPS_IDLE, 		"idle" },
	{ CUPS_PROCESSING,	"processing" },
	{ CUPS_STOPPED,		"stopped" },
	{ 0,			NULL }
};

static int proto_cups = -1;
static int hf_cups_ptype = -1;
static int hf_cups_state = -1;

static gint ett_cups = -1;
static gint ett_cups_ptype = -1;

/* This protocol is heavily related to IPP, but it is CUPS-specific
   and non-standard. */
#define UDP_PORT_CUPS	631
#define PROTO_TAG_CUPS	"CUPS"

static guint get_hex_uint(tvbuff_t *tvb, gint offset,
    gint *next_offset);
static gboolean skip_space(tvbuff_t *tvb, gint offset,
    gint *next_offset);
static const guint8* get_quoted_string(tvbuff_t *tvb, gint offset,
    gint *next_offset, guint *len);
static const guint8* get_unquoted_string(tvbuff_t *tvb, gint offset,
    gint *next_offset, guint *len);

/**********************************************************************/

static void
dissect_cups(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
	proto_tree	*cups_tree = 0;
	proto_tree	*ptype_subtree = 0;
	proto_item	*ti = 0;
	gint		offset = 0;
	gint		next_offset;
	guint		len;
	unsigned int	u;
	const guint8	*str;
	cups_ptype_t	ptype;
	unsigned int	state;

	if (check_col(pinfo->cinfo, COL_PROTOCOL))
		col_set_str(pinfo->cinfo, COL_PROTOCOL, PROTO_TAG_CUPS);
	if (check_col(pinfo->cinfo, COL_INFO))
		col_clear(pinfo->cinfo, COL_INFO);

	if (tree) {
		ti = proto_tree_add_item(tree, proto_cups, tvb, offset, -1,
		    FALSE);
		cups_tree = proto_item_add_subtree(ti, ett_cups);
	}

	/* Format (1450 bytes max.):  */
	/* type state uri ["location" ["info" ["make-and-model"]]]\n */

	ptype = get_hex_uint(tvb, offset, &next_offset);
	len = next_offset - offset;
	if (len != 0) {
		if (cups_tree) {
			ti = proto_tree_add_uint(cups_tree, hf_cups_ptype,
			    tvb, offset, len, ptype);
			ptype_subtree = proto_item_add_subtree(ti,
			    ett_cups_ptype);
			for (u = 0; u < N_CUPS_PTYPE_BITS; u++) {
				proto_tree_add_text(ptype_subtree, tvb,
				    offset, len, "%s",
				    decode_boolean_bitfield(ptype,
				      cups_ptype_bits[u].bit, sizeof (ptype)*8,
				      cups_ptype_bits[u].on_string,
				      cups_ptype_bits[u].off_string));
			}
		}
	}
	offset = next_offset;

	if (!skip_space(tvb, offset, &next_offset))
		return;	/* end of packet */
	offset = next_offset;

	state = get_hex_uint(tvb, offset, &next_offset);
	len = next_offset - offset;
	if (len != 0) {
		if (cups_tree)
			proto_tree_add_uint(cups_tree, hf_cups_state,
			    tvb, offset, len, state);
	}
	offset = next_offset;

	if (!skip_space(tvb, offset, &next_offset))
		return;	/* end of packet */
	offset = next_offset;

	str = get_unquoted_string(tvb, offset, &next_offset, &len);
	if (str == NULL)
		return;	/* separator/terminator not found */
	if (cups_tree)
		proto_tree_add_text(cups_tree, tvb, offset, len,
		    "URI: %.*s",
		    (guint16) len, str);
	if (check_col(pinfo->cinfo, COL_INFO))
		col_add_fstr(pinfo->cinfo, COL_INFO,
		    "%.*s (%s)",
		    (guint16) len, str,
		    val_to_str(state, cups_state_values, "0x%x"));
	offset = next_offset;

	if (!cups_tree)
		return;

	if (!skip_space(tvb, offset, &next_offset))
		return;	/* end of packet */
	offset = next_offset;

	str = get_quoted_string(tvb, offset, &next_offset, &len);
	if (str == NULL)
		return;	/* separator/terminator not found */
	proto_tree_add_text(cups_tree, tvb, offset+1, len,
	    "Location: \"%.*s\"",
	    (guint16) len, str);
	offset = next_offset;

	if (!skip_space(tvb, offset, &next_offset))
		return;	/* end of packet */
	offset = next_offset;

	str = get_quoted_string(tvb, offset, &next_offset, &len);
	if (str == NULL)
		return;	/* separator/terminator not found */
	proto_tree_add_text(cups_tree, tvb, offset+1, len,
	    "Information: \"%.*s\"",
	    (guint16) len, str);
	offset = next_offset;

	if (!skip_space(tvb, offset, &next_offset))
		return;	/* end of packet */
	offset = next_offset;

	str = get_quoted_string(tvb, offset, &next_offset, &len);
	if (str == NULL)
		return;	/* separator/terminator not found */
	proto_tree_add_text(cups_tree, tvb, offset+1, len,
	    "Make and model: \"%.*s\"",
	    (guint16) len, str);
	offset = next_offset;

	return;
}

static guint
get_hex_uint(tvbuff_t *tvb, gint offset, gint *next_offset)
{
	int c;
	guint u = 0;

	while (isxdigit(c = tvb_get_guint8(tvb, offset))) {
		if (isdigit(c))
			c -= '0';
		else if (isupper(c))
			c -= 'A' - 10;
		else if (islower(c))
			c -= 'a' - 10;
		else
			c = 0; /* This should not happen. */

		u = 16*u + c;

		offset++;
	}

	*next_offset = offset;

	return u;
}

static gboolean
skip_space(tvbuff_t *tvb, gint offset, gint *next_offset)
{
	int c;

	while ((c = tvb_get_guint8(tvb, offset)) == ' ')
		offset++;
	if (c == '\r' || c == '\n')
		return FALSE;	/* end of packet */

	*next_offset = offset;

	return TRUE;
}

static const guint8*
get_quoted_string(tvbuff_t *tvb, gint offset, gint *next_offset, guint *len)
{
	int c;
	const guint8* s = NULL;
	guint l = 0;
	gint o;

	c = tvb_get_guint8(tvb, offset);
	if (c == '"') {
		o = tvb_find_guint8(tvb, offset+1, -1, '"');
		if (o != -1) {
			offset++;
			l = o - offset;
			s = tvb_get_ptr(tvb, offset, l);
			offset = o + 1;
		}
	}

	*next_offset = offset;
	*len = l;

	return s;
}

static const guint8*
get_unquoted_string(tvbuff_t *tvb, gint offset, gint *next_offset, guint *len)
{
	const guint8* s = NULL;
	guint l = 0;
	gint o;
	guchar found_needle = 0;

	o = tvb_pbrk_guint8(tvb, offset, -1, (const guint8*)" \t\r\n", NULL);
	if (o != -1) {
		l = o - offset;
		s = tvb_get_ptr(tvb, offset, l);
		offset = o;
	}

	*next_offset = offset;
	*len = l;

	return s;
}

/**********************************************************************/

void
proto_register_cups(void)
{
	static hf_register_info hf[] = {
		/* This one could be split in separate fields. */
		{ &hf_cups_ptype,
			{ "Type", 	"cups.ptype", FT_UINT32, BASE_HEX,
			  NULL, 0x0, "", HFILL }},

		{ &hf_cups_state,
			{ "State",	"cups.state", FT_UINT8, BASE_HEX,
			  VALS(cups_state_values), 0x0, "", HFILL }}
	};

	static gint *ett[] = {
		&ett_cups,
		&ett_cups_ptype
	};

	proto_cups = proto_register_protocol(
	    "Common Unix Printing System (CUPS) Browsing Protocol",
	    "CUPS", "cups");
	proto_register_field_array(proto_cups, hf, array_length(hf));
	proto_register_subtree_array(ett, array_length(ett));
}

void
proto_reg_handoff_cups(void)
{
	dissector_handle_t cups_handle;

	cups_handle = create_dissector_handle(dissect_cups, proto_cups);
	dissector_add("udp.port", UDP_PORT_CUPS, cups_handle);
}
