packet-ipp.c

   1 /* packet-ipp.c
   2  * Routines for IPP packet disassembly
   3  *
   4  * Guy Harris <guy@alum.mit.edu>
   5  *
   6  * $Id: packet-ipp.c,v 1.22 2001/01/11 06:30:54 guy Exp $
   7  *
   8  * Ethereal - Network traffic analyzer
   9  * By Gerald Combs <gerald@zing.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version 2
  16  * of the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  26  *
  27  *
  28  */
  29
  30 #ifdef HAVE_CONFIG_H
  31 #include "config.h"
  32 #endif
  33
  34 #ifdef HAVE_SYS_TYPES_H
  35 #include <sys/types.h>
  36 #endif
  37
  38 #include <string.h>
  39 #include <ctype.h>
  40
  41 #include <glib.h>
  42 #include "packet.h"
  43 #include "strutil.h"
  44 #include "packet-http.h"
  45
  46 static int proto_ipp = -1;
  47
  48 static gint ett_ipp = -1;
  49 static gint ett_ipp_as = -1;
  50 static gint ett_ipp_attr = -1;
  51
  52 #define PRINT_JOB               0x0002
  53 #define PRINT_URI               0x0003
  54 #define VALIDATE_JOB            0x0004
  55 #define CREATE_JOB              0x0005
  56 #define SEND_DOCUMENT           0x0006
  57 #define SEND_URI                0x0007
  58 #define CANCEL_JOB              0x0008
  59 #define GET_JOB_ATTRIBUTES      0x0009
  60 #define GET_JOBS                0x000A
  61 #define GET_PRINTER_ATTRIBUTES  0x000B
  62
  63 static const value_string operation_vals[] = {
  64     { PRINT_JOB,              "Print-Job" },
  65     { PRINT_URI,              "Print-URI" },
  66     { VALIDATE_JOB,           "Validate-Job" },
  67     { CREATE_JOB,             "Create-Job" },
  68     { SEND_DOCUMENT,          "Send-Document" },
  69     { SEND_URI,               "Send-URI" },
  70     { CANCEL_JOB,             "Cancel-Job" },
  71     { GET_JOB_ATTRIBUTES,     "Get-Job-Attributes" },
  72     { GET_JOBS,               "Get-Jobs" },
  73     { GET_PRINTER_ATTRIBUTES, "Get-Printer-Attributes" },
  74     { 0,                      NULL }
  75 };
  76
  77 #define STATUS_SUCCESSFUL       0x0000
  78 #define STATUS_INFORMATIONAL    0x0100
  79 #define STATUS_REDIRECTION      0x0200
  80 #define STATUS_CLIENT_ERROR     0x0400
  81 #define STATUS_SERVER_ERROR     0x0500
  82
  83 #define STATUS_TYPE_MASK        0xFF00
  84
  85 #define SUCCESSFUL_OK                           0x0000
  86 #define SUCCESSFUL_OK_IGN_OR_SUB_ATTR           0x0001
  87 #define SUCCESSFUL_OK_CONFLICTING_ATTR          0x0002
  88
  89 #define CLIENT_ERROR_BAD_REQUEST                0x0400
  90 #define CLIENT_ERROR_FORBIDDEN                  0x0401
  91 #define CLIENT_ERROR_NOT_AUTHENTICATED          0x0402
  92 #define CLIENT_ERROR_NOT_AUTHORIZED             0x0403
  93 #define CLIENT_ERROR_NOT_POSSIBLE               0x0404
  94 #define CLIENT_ERROR_TIMEOUT                    0x0405
  95 #define CLIENT_ERROR_NOT_FOUND                  0x0406
  96 #define CLIENT_ERROR_GONE                       0x0407
  97 #define CLIENT_ERROR_REQ_ENTITY_TOO_LRG         0x0408
  98 #define CLIENT_ERROR_REQ_VALUE_TOO_LONG         0x0409
  99 #define CLIENT_ERROR_DOC_FMT_NOT_SUPP           0x040A
 100 #define CLIENT_ERROR_ATTR_OR_VAL_NOT_SUPP       0x040B
 101 #define CLIENT_ERROR_URI_SCHEME_NOT_SUPP        0x040C
 102 #define CLIENT_ERROR_CHARSET_NOT_SUPP           0x040D
 103 #define CLIENT_ERROR_CONFLICTING_ATTRS          0x040E
 104
 105 #define SERVER_ERROR_INTERNAL_ERROR             0x0500
 106 #define SERVER_ERROR_OPERATION_NOT_SUPP         0x0501
 107 #define SERVER_ERROR_SERVICE_UNAVAIL            0x0502
 108 #define SERVER_ERROR_VERSION_NOT_SUPP           0x0503
 109 #define SERVER_ERROR_DEVICE_ERROR               0x0504
 110 #define SERVER_ERROR_TEMPORARY_ERROR            0x0505
 111 #define SERVER_ERROR_NOT_ACCEPTING_JOBS         0x0506
 112 #define SERVER_ERROR_BUSY                       0x0507
 113 #define SERVER_ERROR_JOB_CANCELED               0x0508
 114
 115 static const value_string status_vals[] = {
 116     { SUCCESSFUL_OK,                     "Successful-OK" },
 117     { SUCCESSFUL_OK_IGN_OR_SUB_ATTR,     "Successful-OK-Ignored-Or-Substituted-Attributes" },
 118     { SUCCESSFUL_OK_CONFLICTING_ATTR,    "Successful-OK-Conflicting-Attributes" },
 119     { CLIENT_ERROR_BAD_REQUEST,          "Client-Error-Bad-Request" },
 120     { CLIENT_ERROR_FORBIDDEN,            "Client-Error-Forbidden" },
 121     { CLIENT_ERROR_NOT_AUTHENTICATED,    "Client-Error-Not-Authenticated" },
 122     { CLIENT_ERROR_NOT_AUTHORIZED,       "Client-Error-Not-Authorized" },
 123     { CLIENT_ERROR_NOT_POSSIBLE,         "Client-Error-Not-Possible" },
 124     { CLIENT_ERROR_TIMEOUT,              "Client-Error-Timeout" },
 125     { CLIENT_ERROR_NOT_FOUND,            "Client-Error-Not-Found" },
 126     { CLIENT_ERROR_GONE,                 "Client-Error-Gone" },
 127     { CLIENT_ERROR_REQ_ENTITY_TOO_LRG,   "Client-Error-Request-Entity-Too-Large" },
 128     { CLIENT_ERROR_REQ_VALUE_TOO_LONG,   "Client-Error-Request-Value-Too-Long" },
 129     { CLIENT_ERROR_DOC_FMT_NOT_SUPP,     "Client-Error-Document-Format-Not-Supported" },
 130     { CLIENT_ERROR_ATTR_OR_VAL_NOT_SUPP, "Client-Error-Attributes-Or-Values-Not-Supported" },
 131     { CLIENT_ERROR_URI_SCHEME_NOT_SUPP,  "Client-Error-URI-Scheme-Not-Supported" },
 132     { CLIENT_ERROR_CHARSET_NOT_SUPP,     "Client-Error-Charset-Not-Supported" },
 133     { CLIENT_ERROR_CONFLICTING_ATTRS,    "Client-Error-Conflicting-Attributes" },
 134     { SERVER_ERROR_INTERNAL_ERROR,       "Server-Error-Internal-Error" },
 135     { SERVER_ERROR_OPERATION_NOT_SUPP,   "Server-Error-Operation-Not-Supported" },
 136     { SERVER_ERROR_SERVICE_UNAVAIL,      "Server-Error-Service-Unavailable" },
 137     { SERVER_ERROR_VERSION_NOT_SUPP,     "Server-Error-Version-Not-Supported" },
 138     { SERVER_ERROR_DEVICE_ERROR,         "Server-Error-Device-Error" },
 139     { SERVER_ERROR_TEMPORARY_ERROR,      "Server-Error-Temporary-Error" },
 140     { SERVER_ERROR_NOT_ACCEPTING_JOBS,   "Server-Error-Not-Accepting-Jobs" },
 141     { SERVER_ERROR_BUSY,                 "Server-Error-Busy" },
 142     { SERVER_ERROR_JOB_CANCELED,         "Server-Error-Job-Canceled" },
 143     { 0,                                 NULL }
 144 };
 145
 146 static int parse_attributes(tvbuff_t *tvb, int offset, proto_tree *tree);
 147 static proto_tree *add_integer_tree(proto_tree *tree, tvbuff_t *tvb,
 148     int offset, int name_length, int value_length);
 149 static void add_integer_value(guint tag, gchar *tag_desc, proto_tree *tree,
 150     tvbuff_t *tvb, int offset, int name_length, int value_length);
 151 static proto_tree *add_octetstring_tree(proto_tree *tree, tvbuff_t *tvb,
 152     int offset, int name_length, int value_length);
 153 static void add_octetstring_value(guint tag, gchar *tag_desc, proto_tree *tree,
 154     tvbuff_t *tvb, int offset, int name_length, int value_length);
 155 static proto_tree *add_charstring_tree(proto_tree *tree, tvbuff_t *tvb,
 156     int offset, int name_length, int value_length);
 157 static void add_charstring_value(guint tag, gchar *tag_desc, proto_tree *tree,
 158     tvbuff_t *tvb, int offset, int name_length, int value_length);
 159 static int add_value_head(guint tag, gchar *tag_desc, proto_tree *tree,
 160     tvbuff_t *tvb, int offset, int name_length, int value_length);
 161
 162 static void
 163 dissect_ipp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 164 {
 165         proto_tree *ipp_tree;
 166         proto_item *ti;
 167         int offset = 0;
 168         gboolean is_request = (pinfo->destport == 631);
 169         guint16 status_code;
 170         gchar *status_fmt;
 171
 172         CHECK_DISPLAY_AS_DATA(proto_ipp, tvb, pinfo, tree);
 173
 174         pinfo->current_proto = "IPP";
 175
 176         if (check_col(pinfo->fd, COL_PROTOCOL))
 177                 col_set_str(pinfo->fd, COL_PROTOCOL, "IPP");
 178         if (check_col(pinfo->fd, COL_INFO)) {
 179                 if (is_request)
 180                         col_set_str(pinfo->fd, COL_INFO, "IPP request");
 181                 else
 182                         col_set_str(pinfo->fd, COL_INFO, "IPP response");
 183         }
 184
 185         if (tree) {
 186                 ti = proto_tree_add_item(tree, proto_ipp, tvb, offset,
 187                     tvb_length_remaining(tvb, offset), FALSE);
 188                 ipp_tree = proto_item_add_subtree(ti, ett_ipp);
 189
 190                 proto_tree_add_text(ipp_tree, tvb, offset, 2, "Version: %u.%u",
 191                     tvb_get_guint8(tvb, offset),
 192                     tvb_get_guint8(tvb, offset + 1));
 193                 offset += 2;
 194
 195                 if (is_request) {
 196                         proto_tree_add_text(ipp_tree, tvb, offset, 2, "Operation-id: %s",
 197                             val_to_str(tvb_get_ntohs(tvb, offset), operation_vals,
 198                                 "Unknown (0x%04x)"));
 199                 } else {
 200                         status_code = tvb_get_ntohs(tvb, offset);
 201                         switch (status_code & STATUS_TYPE_MASK) {
 202
 203                         case STATUS_SUCCESSFUL:
 204                                 status_fmt = "Successful (0x%04x)";
 205                                 break;
 206
 207                         case STATUS_INFORMATIONAL:
 208                                 status_fmt = "Informational (0x%04x)";
 209                                 break;
 210
 211                         case STATUS_REDIRECTION:
 212                                 status_fmt = "Redirection (0x%04x)";
 213                                 break;
 214
 215                         case STATUS_CLIENT_ERROR:
 216                                 status_fmt = "Client error (0x%04x)";
 217                                 break;
 218
 219                         case STATUS_SERVER_ERROR:
 220                                 status_fmt = "Server error (0x%04x)";
 221                                 break;
 222
 223                         default:
 224                                 status_fmt = "Unknown (0x%04x)";
 225                                 break;
 226                         }
 227                         proto_tree_add_text(ipp_tree, tvb, offset, 2, "Status-code: %s",
 228                             val_to_str(status_code, status_vals, status_fmt));
 229                 }
 230                 offset += 2;
 231
 232                 proto_tree_add_text(ipp_tree, tvb, offset, 4, "Request ID: %u",
 233                     tvb_get_ntohl(tvb, offset));
 234                 offset += 4;
 235
 236                 offset = parse_attributes(tvb, offset, ipp_tree);
 237
 238                 if (tvb_offset_exists(tvb, offset))
 239                         dissect_data(tvb, offset, pinfo, ipp_tree);
 240         }
 241 }
 242
 243 #define TAG_TYPE(tag)           ((tag) & 0xF0)
 244 #define TAG_TYPE_DELIMITER      0x00
 245 #define TAG_TYPE_INTEGER        0x20
 246 #define TAG_TYPE_OCTETSTRING    0x30
 247 #define TAG_TYPE_CHARSTRING     0x40
 248
 249 #define TAG_END_OF_ATTRIBUTES   0x03
 250
 251 #define TAG_INTEGER             0x21
 252 #define TAG_BOOLEAN             0x22
 253 #define TAG_ENUM                0x23
 254
 255 #define TAG_OCTETSTRING         0x30
 256 #define TAG_DATETIME            0x31
 257 #define TAG_RESOLUTION          0x32
 258 #define TAG_RANGEOFINTEGER      0x33
 259 #define TAG_TEXTWITHLANGUAGE    0x35
 260 #define TAG_NAMEWITHLANGUAGE    0x36
 261
 262 #define TAG_TEXTWITHOUTLANGUAGE 0x41
 263 #define TAG_NAMEWITHOUTLANGUAGE 0x42
 264 #define TAG_KEYWORD             0x44
 265 #define TAG_URI                 0x45
 266 #define TAG_URISCHEME           0x46
 267 #define TAG_CHARSET             0x47
 268 #define TAG_NATURALLANGUAGE     0x48
 269 #define TAG_MIMEMEDIATYPE       0x49
 270
 271 static const value_string tag_vals[] = {
 272         /* Delimiter tags */
 273         { 0x01,                    "Operation attributes" },
 274         { 0x02,                    "Job attributes" },
 275         { TAG_END_OF_ATTRIBUTES,   "End of attributes" },
 276         { 0x04,                    "Printer attributes" },
 277         { 0x05,                    "Unsupported attributes" },
 278
 279         /* Value tags */
 280         { 0x10,                    "Unsupported" },
 281         { 0x12,                    "Unknown" },
 282         { 0x13,                    "No value" },
 283         { TAG_INTEGER,             "Integer" },
 284         { TAG_BOOLEAN,             "Boolean" },
 285         { TAG_ENUM,                "Enum" },
 286         { TAG_OCTETSTRING,         "Octet string" },
 287         { TAG_DATETIME,            "Date/Time" },
 288         { TAG_RESOLUTION,          "Resolution" },
 289         { TAG_RANGEOFINTEGER,      "Range of integer" },
 290         { TAG_TEXTWITHLANGUAGE,    "Text with language" },
 291         { TAG_NAMEWITHLANGUAGE,    "Name with language" },
 292         { TAG_TEXTWITHOUTLANGUAGE, "Text without language" },
 293         { TAG_NAMEWITHOUTLANGUAGE, "Name without language" },
 294         { TAG_KEYWORD,             "Keyword" },
 295         { TAG_URI,                 "URI" },
 296         { TAG_URISCHEME,           "URI scheme" },
 297         { TAG_CHARSET,             "Character set" },
 298         { TAG_NATURALLANGUAGE,     "Natural language" },
 299         { TAG_MIMEMEDIATYPE,       "MIME media type" },
 300         { 0,                       NULL }
 301 };
 302
 303 static int
 304 parse_attributes(tvbuff_t *tvb, int offset, proto_tree *tree)
 305 {
 306         guint8 tag;
 307         gchar *tag_desc;
 308         int name_length, value_length;
 309         proto_tree *as_tree = tree;
 310         proto_item *tas = NULL;
 311         int start_offset = offset;
 312         proto_tree *attr_tree = tree;
 313
 314         while (tvb_offset_exists(tvb, offset)) {
 315                 tag = tvb_get_guint8(tvb, offset);
 316                 tag_desc = val_to_str(tag, tag_vals, "Reserved (0x%02x)");
 317                 if (TAG_TYPE(tag) == TAG_TYPE_DELIMITER) {
 318                         /*
 319                          * If we had an attribute sequence we were
 320                          * working on, we're done with it; set its
 321                          * length to the length of all the stuff
 322                          * we've done so far.
 323                          */
 324                         if (tas != NULL)
 325                                 proto_item_set_len(tas, offset - start_offset);
 326
 327                         /*
 328                          * This tag starts a new attribute sequence;
 329                          * create a new tree under this tag when we see
 330                          * a non-delimiter tag, under which to put
 331                          * those attributes.
 332                          */
 333                         as_tree = NULL;
 334                         attr_tree = tree;
 335
 336                         /*
 337                          * Remember the offset at which this attribute
 338                          * sequence started, so we can use it to compute
 339                          * its length when it's finished.
 340                          */
 341                         start_offset = offset;
 342
 343                         /*
 344                          * Now create a new item for this tag.
 345                          */
 346                         tas = proto_tree_add_text(tree, tvb, offset, 1,
 347                             "%s", tag_desc);
 348                         offset++;
 349                         if (tag == TAG_END_OF_ATTRIBUTES) {
 350                                 /*
 351                                  * No more attributes.
 352                                  */
 353                                 break;
 354                         }
 355                 } else {
 356                         /*
 357                          * Value tag - get the name length.
 358                          */
 359                         name_length = tvb_get_ntohs(tvb, offset + 1);
 360
 361                         /*
 362                          * OK, get the value length.
 363                          */
 364                         value_length = tvb_get_ntohs(tvb, offset + 1 + 2 + name_length);
 365
 366                         /*
 367                          * OK, does the value run past the end of the
 368                          * frame?
 369                          */
 370                         if (as_tree == NULL) {
 371                                 /*
 372                                  * OK, there's an attribute to hang
 373                                  * under a delimiter tag, but we don't
 374                                  * have a tree for that tag yet; create
 375                                  * a tree.
 376                                  */
 377                                 as_tree = proto_item_add_subtree(tas,
 378                                     ett_ipp_as);
 379                                 attr_tree = as_tree;
 380                         }
 381
 382                         switch (TAG_TYPE(tag)) {
 383
 384                         case TAG_TYPE_INTEGER:
 385                                 if (name_length != 0) {
 386                                         /*
 387                                          * This is an attribute, not
 388                                          * an additional value, so
 389                                          * start a tree for it.
 390                                          */
 391                                         attr_tree = add_integer_tree(as_tree,
 392                                             tvb, offset, name_length,
 393                                             value_length);
 394                                 }
 395                                 add_integer_value(tag, tag_desc, attr_tree, tvb,
 396                                     offset, name_length, value_length);
 397                                 break;
 398
 399                         case TAG_TYPE_OCTETSTRING:
 400                                 if (name_length != 0) {
 401                                         /*
 402                                          * This is an attribute, not
 403                                          * an additional value, so
 404                                          * start a tree for it.
 405                                          */
 406                                         attr_tree = add_octetstring_tree(as_tree,
 407                                             tvb, offset, name_length,
 408                                             value_length);
 409                                 }
 410                                 add_octetstring_value(tag, tag_desc,
 411                                     attr_tree, tvb, offset, name_length,
 412                                     value_length);
 413                                 break;
 414
 415                         case TAG_TYPE_CHARSTRING:
 416                                 if (name_length != 0) {
 417                                         /*
 418                                          * This is an attribute, not
 419                                          * an additional value, so
 420                                          * start a tree for it.
 421                                          */
 422                                         attr_tree = add_charstring_tree(as_tree,
 423                                             tvb, offset, name_length,
 424                                             value_length);
 425                                 }
 426                                 add_charstring_value(tag, tag_desc,
 427                                     attr_tree, tvb, offset, name_length,
 428                                     value_length);
 429                                 break;
 430                         }
 431                         offset += 1 + 2 + name_length + 2 + value_length;
 432                 }
 433         }
 434
 435         return offset;
 436 }
 437
 438 static proto_tree *
 439 add_integer_tree(proto_tree *tree, tvbuff_t *tvb, int offset,
 440     int name_length, int value_length)
 441 {
 442         proto_item *ti;
 443
 444         if (value_length != 4) {
 445                 ti = proto_tree_add_text(tree, tvb, offset,
 446                     1 + 2 + name_length + 2 + value_length,
 447                     "%.*s: Invalid integer (length is %u, should be 4)",
 448                     name_length,
 449                     tvb_get_ptr(tvb, offset + 1 + 2, name_length),
 450                     value_length);
 451         } else {
 452                 ti = proto_tree_add_text(tree, tvb, offset,
 453                     1 + 2 + name_length + 2 + value_length,
 454                     "%.*s: %u",
 455                     name_length,
 456                     tvb_get_ptr(tvb, offset + 1 + 2, name_length),
 457                     tvb_get_ntohl(tvb, offset + 1 + 2 + name_length + 2));
 458         }
 459         return proto_item_add_subtree(ti, ett_ipp_attr);
 460 }
 461
 462 static void
 463 add_integer_value(guint tag, gchar *tag_desc, proto_tree *tree,
 464     tvbuff_t *tvb, int offset, int name_length, int value_length)
 465 {
 466         offset = add_value_head(tag, tag_desc, tree, tvb, offset,
 467             name_length, value_length);
 468         if (value_length == 4) {
 469                 proto_tree_add_text(tree, tvb, offset, value_length,
 470                     "Value: %u", tvb_get_ntohl(tvb, offset));
 471         }
 472 }
 473
 474 static proto_tree *
 475 add_octetstring_tree(proto_tree *tree, tvbuff_t *tvb, int offset,
 476     int name_length, int value_length)
 477 {
 478         proto_item *ti;
 479
 480         ti = proto_tree_add_text(tree, tvb, offset,
 481             1 + 2 + name_length + 2 + value_length,
 482             "%.*s: %s",
 483             name_length,
 484             tvb_get_ptr(tvb, offset + 1 + 2, name_length),
 485             tvb_bytes_to_str(tvb, offset + 1 + 2 + name_length + 2, value_length));
 486         return proto_item_add_subtree(ti, ett_ipp_attr);
 487 }
 488
 489 static void
 490 add_octetstring_value(guint tag, gchar *tag_desc, proto_tree *tree,
 491     tvbuff_t *tvb, int offset, int name_length, int value_length)
 492 {
 493         offset = add_value_head(tag, tag_desc, tree, tvb, offset,
 494             name_length, value_length);
 495         proto_tree_add_text(tree, tvb, offset, value_length,
 496             "Value: %s", tvb_bytes_to_str(tvb, offset, value_length));
 497 }
 498
 499 static proto_tree *
 500 add_charstring_tree(proto_tree *tree, tvbuff_t *tvb, int offset,
 501     int name_length, int value_length)
 502 {
 503         proto_item *ti;
 504
 505         ti = proto_tree_add_text(tree, tvb, offset,
 506             1 + 2 + name_length + 2 + value_length,
 507             "%.*s: %.*s",
 508             name_length,
 509             tvb_get_ptr(tvb, offset + 1 + 2, name_length),
 510             value_length,
 511             tvb_get_ptr(tvb, offset + 1 + 2 + name_length + 2, value_length));
 512         return proto_item_add_subtree(ti, ett_ipp_attr);
 513 }
 514
 515 static void
 516 add_charstring_value(guint tag, gchar *tag_desc, proto_tree *tree,
 517     tvbuff_t *tvb, int offset, int name_length, int value_length)
 518 {
 519         offset = add_value_head(tag, tag_desc, tree, tvb, offset,
 520             name_length, value_length);
 521         proto_tree_add_text(tree, tvb, offset, value_length,
 522             "Value: %.*s", value_length, tvb_get_ptr(tvb, offset, value_length));
 523 }
 524
 525 static int
 526 add_value_head(guint tag, gchar *tag_desc, proto_tree *tree,
 527     tvbuff_t *tvb, int offset, int name_length, int value_length)
 528 {
 529         proto_tree_add_text(tree, tvb, offset, 1, "Tag: %s", tag_desc);
 530         offset += 1;
 531         proto_tree_add_text(tree, tvb, offset, 2, "Name length: %u",
 532             name_length);
 533         offset += 2;
 534         if (name_length != 0) {
 535                 proto_tree_add_text(tree, tvb, offset, name_length,
 536                     "Name: %.*s", name_length,
 537                     tvb_get_ptr(tvb, offset, name_length));
 538         }
 539         offset += name_length;
 540         proto_tree_add_text(tree, tvb, offset, 2, "Value length: %u",
 541             value_length);
 542         offset += 2;
 543         return offset;
 544 }
 545
 546 void
 547 proto_register_ipp(void)
 548 {
 549 /*        static hf_register_info hf[] = {
 550                 { &variable,
 551                 { "Name",           "ipp.abbreviation", TYPE, VALS_POINTER }},
 552         };*/
 553         static gint *ett[] = {
 554                 &ett_ipp,
 555                 &ett_ipp_as,
 556                 &ett_ipp_attr,
 557         };
 558
 559         proto_ipp = proto_register_protocol("Internet Printing Protocol",
 560             "IPP", "ipp");
 561  /*       proto_register_field_array(proto_ipp, hf, array_length(hf));*/
 562         proto_register_subtree_array(ett, array_length(ett));
 563 }
 564
 565 void
 566 proto_reg_handoff_ipp(void)
 567 {
 568         /*
 569          * Register ourselves as running atop HTTP and using port 631.
 570          */
 571         http_dissector_add(631, dissect_ipp, proto_ipp);
 572 }