1/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2/* dbus-marshal-validate.c Validation routines for marshaled data
3 *
4 * Copyright (C) 2005 Red Hat, Inc.
5 *
6 * Licensed under the Academic Free License version 2.1
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
21 *
22 */
23
24#include <config.h>
25#include "dbus-internals.h"
26#include "dbus-marshal-validate.h"
27#include "dbus-marshal-recursive.h"
28#include "dbus-marshal-basic.h"
29#include "dbus-signature.h"
30#include "dbus-string.h"
31
32/**
33 * @addtogroup DBusMarshal
34 *
35 * @{
36 */
37
38/**
39 * Verifies that the range of type_str from type_pos to type_end is a
40 * valid signature.  If this function returns #TRUE, it will be safe
41 * to iterate over the signature with a types-only #DBusTypeReader.
42 * The range passed in should NOT include the terminating
43 * nul/DBUS_TYPE_INVALID.
44 *
45 * @param type_str the string
46 * @param type_pos where the typecodes start
47 * @param len length of typecodes
48 * @returns #DBUS_VALID if valid, reason why invalid otherwise
49 */
50DBusValidity
51_dbus_validate_signature_with_reason (const DBusString *type_str,
52                                      int               type_pos,
53                                      int               len)
54{
55  const unsigned char *p;
56  const unsigned char *end;
57  int last;
58  int struct_depth;
59  int array_depth;
60  int dict_entry_depth;
61  DBusValidity result;
62
63  int element_count;
64  DBusList *element_count_stack;
65
66  result = DBUS_VALID;
67  element_count_stack = NULL;
68
69  if (!_dbus_list_append (&element_count_stack, _DBUS_INT_TO_POINTER (0)))
70    {
71      result = DBUS_VALIDITY_UNKNOWN_OOM_ERROR;
72      goto out;
73    }
74
75  _dbus_assert (type_str != NULL);
76  _dbus_assert (type_pos < _DBUS_INT32_MAX - len);
77  _dbus_assert (len >= 0);
78  _dbus_assert (type_pos >= 0);
79
80  if (len > DBUS_MAXIMUM_SIGNATURE_LENGTH)
81    {
82      result = DBUS_INVALID_SIGNATURE_TOO_LONG;
83      goto out;
84    }
85
86  p = _dbus_string_get_const_data_len (type_str, type_pos, 0);
87
88  end = _dbus_string_get_const_data_len (type_str, type_pos + len, 0);
89  struct_depth = 0;
90  array_depth = 0;
91  dict_entry_depth = 0;
92  last = DBUS_TYPE_INVALID;
93
94  while (p != end)
95    {
96      switch (*p)
97        {
98        case DBUS_TYPE_BYTE:
99        case DBUS_TYPE_BOOLEAN:
100        case DBUS_TYPE_INT16:
101        case DBUS_TYPE_UINT16:
102        case DBUS_TYPE_INT32:
103        case DBUS_TYPE_UINT32:
104        case DBUS_TYPE_UNIX_FD:
105        case DBUS_TYPE_INT64:
106        case DBUS_TYPE_UINT64:
107        case DBUS_TYPE_DOUBLE:
108        case DBUS_TYPE_STRING:
109        case DBUS_TYPE_OBJECT_PATH:
110        case DBUS_TYPE_SIGNATURE:
111        case DBUS_TYPE_VARIANT:
112          break;
113
114        case DBUS_TYPE_ARRAY:
115          array_depth += 1;
116          if (array_depth > DBUS_MAXIMUM_TYPE_RECURSION_DEPTH)
117            {
118              result = DBUS_INVALID_EXCEEDED_MAXIMUM_ARRAY_RECURSION;
119              goto out;
120            }
121          break;
122
123        case DBUS_STRUCT_BEGIN_CHAR:
124          struct_depth += 1;
125
126          if (struct_depth > DBUS_MAXIMUM_TYPE_RECURSION_DEPTH)
127            {
128              result = DBUS_INVALID_EXCEEDED_MAXIMUM_STRUCT_RECURSION;
129              goto out;
130            }
131
132          if (!_dbus_list_append (&element_count_stack,
133                             _DBUS_INT_TO_POINTER (0)))
134            {
135              result = DBUS_VALIDITY_UNKNOWN_OOM_ERROR;
136              goto out;
137            }
138
139          break;
140
141        case DBUS_STRUCT_END_CHAR:
142          if (struct_depth == 0)
143            {
144              result = DBUS_INVALID_STRUCT_ENDED_BUT_NOT_STARTED;
145              goto out;
146            }
147
148          if (last == DBUS_STRUCT_BEGIN_CHAR)
149            {
150              result = DBUS_INVALID_STRUCT_HAS_NO_FIELDS;
151              goto out;
152            }
153
154          _dbus_list_pop_last (&element_count_stack);
155
156          struct_depth -= 1;
157          break;
158
159        case DBUS_DICT_ENTRY_BEGIN_CHAR:
160          if (last != DBUS_TYPE_ARRAY)
161            {
162              result = DBUS_INVALID_DICT_ENTRY_NOT_INSIDE_ARRAY;
163              goto out;
164            }
165
166          dict_entry_depth += 1;
167
168          if (dict_entry_depth > DBUS_MAXIMUM_TYPE_RECURSION_DEPTH)
169            {
170              result = DBUS_INVALID_EXCEEDED_MAXIMUM_DICT_ENTRY_RECURSION;
171              goto out;
172            }
173
174          if (!_dbus_list_append (&element_count_stack,
175                             _DBUS_INT_TO_POINTER (0)))
176            {
177              result = DBUS_VALIDITY_UNKNOWN_OOM_ERROR;
178              goto out;
179            }
180
181          break;
182
183        case DBUS_DICT_ENTRY_END_CHAR:
184          if (dict_entry_depth == 0)
185            {
186              result = DBUS_INVALID_DICT_ENTRY_ENDED_BUT_NOT_STARTED;
187              goto out;
188            }
189
190          dict_entry_depth -= 1;
191
192          element_count =
193            _DBUS_POINTER_TO_INT (_dbus_list_pop_last (&element_count_stack));
194
195          if (element_count != 2)
196            {
197              if (element_count == 0)
198                result = DBUS_INVALID_DICT_ENTRY_HAS_NO_FIELDS;
199              else if (element_count == 1)
200                result = DBUS_INVALID_DICT_ENTRY_HAS_ONLY_ONE_FIELD;
201              else
202                result = DBUS_INVALID_DICT_ENTRY_HAS_TOO_MANY_FIELDS;
203
204              goto out;
205            }
206          break;
207
208        case DBUS_TYPE_STRUCT:     /* doesn't appear in signatures */
209        case DBUS_TYPE_DICT_ENTRY: /* ditto */
210        default:
211          result = DBUS_INVALID_UNKNOWN_TYPECODE;
212	  goto out;
213        }
214
215      if (*p != DBUS_TYPE_ARRAY &&
216          *p != DBUS_DICT_ENTRY_BEGIN_CHAR &&
217	  *p != DBUS_STRUCT_BEGIN_CHAR)
218        {
219          element_count =
220            _DBUS_POINTER_TO_INT (_dbus_list_pop_last (&element_count_stack));
221
222          ++element_count;
223
224          if (!_dbus_list_append (&element_count_stack,
225                             _DBUS_INT_TO_POINTER (element_count)))
226            {
227              result = DBUS_VALIDITY_UNKNOWN_OOM_ERROR;
228              goto out;
229            }
230        }
231
232      if (array_depth > 0)
233        {
234          if (*p == DBUS_TYPE_ARRAY && p != end)
235            {
236	       const char *p1;
237	       p1 = p + 1;
238               if (*p1 == DBUS_STRUCT_END_CHAR ||
239                   *p1 == DBUS_DICT_ENTRY_END_CHAR)
240                 {
241                   result = DBUS_INVALID_MISSING_ARRAY_ELEMENT_TYPE;
242                   goto out;
243                 }
244            }
245          else
246	    {
247              array_depth = 0;
248	    }
249        }
250
251      if (last == DBUS_DICT_ENTRY_BEGIN_CHAR)
252        {
253          if (!(_dbus_type_is_valid (*p) && dbus_type_is_basic (*p)))
254            {
255              result = DBUS_INVALID_DICT_KEY_MUST_BE_BASIC_TYPE;
256              goto out;
257            }
258        }
259
260      last = *p;
261      ++p;
262    }
263
264
265  if (array_depth > 0)
266    {
267      result = DBUS_INVALID_MISSING_ARRAY_ELEMENT_TYPE;
268      goto out;
269    }
270
271  if (struct_depth > 0)
272    {
273       result = DBUS_INVALID_STRUCT_STARTED_BUT_NOT_ENDED;
274       goto out;
275    }
276
277  if (dict_entry_depth > 0)
278    {
279      result =  DBUS_INVALID_DICT_ENTRY_STARTED_BUT_NOT_ENDED;
280      goto out;
281    }
282
283  _dbus_assert (last != DBUS_TYPE_ARRAY);
284  _dbus_assert (last != DBUS_STRUCT_BEGIN_CHAR);
285  _dbus_assert (last != DBUS_DICT_ENTRY_BEGIN_CHAR);
286
287  result = DBUS_VALID;
288
289out:
290  _dbus_list_clear (&element_count_stack);
291  return result;
292}
293
294/* note: this function is also used to validate the header's values,
295 * since the header is a valid body with a particular signature.
296 */
297static DBusValidity
298validate_body_helper (DBusTypeReader       *reader,
299                      int                   byte_order,
300                      dbus_bool_t           walk_reader_to_end,
301                      int                   total_depth,
302                      const unsigned char  *p,
303                      const unsigned char  *end,
304                      const unsigned char **new_p)
305{
306  int current_type;
307
308  /* The spec allows arrays and structs to each nest 32, for total
309   * nesting of 2*32. We want to impose the same limit on "dynamic"
310   * value nesting (not visible in the signature) which is introduced
311   * by DBUS_TYPE_VARIANT.
312   */
313  if (total_depth > (DBUS_MAXIMUM_TYPE_RECURSION_DEPTH * 2))
314    {
315      return DBUS_INVALID_NESTED_TOO_DEEPLY;
316    }
317
318  while ((current_type = _dbus_type_reader_get_current_type (reader)) != DBUS_TYPE_INVALID)
319    {
320      const unsigned char *a;
321      int alignment;
322
323#if 0
324      _dbus_verbose ("   validating value of type %s type reader %p type_pos %d p %p end %p %d remain\n",
325                     _dbus_type_to_string (current_type), reader, reader->type_pos, p, end,
326                     (int) (end - p));
327#endif
328
329      /* Guarantee that p has one byte to look at */
330      if (p == end)
331        return DBUS_INVALID_NOT_ENOUGH_DATA;
332
333      switch (current_type)
334        {
335        case DBUS_TYPE_BYTE:
336          ++p;
337          break;
338
339        case DBUS_TYPE_BOOLEAN:
340        case DBUS_TYPE_INT16:
341        case DBUS_TYPE_UINT16:
342        case DBUS_TYPE_INT32:
343        case DBUS_TYPE_UINT32:
344        case DBUS_TYPE_UNIX_FD:
345        case DBUS_TYPE_INT64:
346        case DBUS_TYPE_UINT64:
347        case DBUS_TYPE_DOUBLE:
348          alignment = _dbus_type_get_alignment (current_type);
349          a = _DBUS_ALIGN_ADDRESS (p, alignment);
350          if (a >= end)
351            return DBUS_INVALID_NOT_ENOUGH_DATA;
352          while (p != a)
353            {
354              if (*p != '\0')
355                return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
356              ++p;
357            }
358
359          if (current_type == DBUS_TYPE_BOOLEAN)
360            {
361              dbus_uint32_t v = _dbus_unpack_uint32 (byte_order,
362                                                     p);
363              if (!(v == 0 || v == 1))
364                return DBUS_INVALID_BOOLEAN_NOT_ZERO_OR_ONE;
365            }
366
367          p += alignment;
368          break;
369
370        case DBUS_TYPE_ARRAY:
371        case DBUS_TYPE_STRING:
372        case DBUS_TYPE_OBJECT_PATH:
373          {
374            dbus_uint32_t claimed_len;
375
376            a = _DBUS_ALIGN_ADDRESS (p, 4);
377            if (a + 4 > end)
378              return DBUS_INVALID_NOT_ENOUGH_DATA;
379            while (p != a)
380              {
381                if (*p != '\0')
382                  return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
383                ++p;
384              }
385
386            claimed_len = _dbus_unpack_uint32 (byte_order, p);
387            p += 4;
388
389            /* p may now be == end */
390            _dbus_assert (p <= end);
391
392            if (current_type == DBUS_TYPE_ARRAY)
393              {
394                int array_elem_type = _dbus_type_reader_get_element_type (reader);
395
396                if (!_dbus_type_is_valid (array_elem_type))
397                  {
398                    return DBUS_INVALID_UNKNOWN_TYPECODE;
399                  }
400
401                alignment = _dbus_type_get_alignment (array_elem_type);
402
403                a = _DBUS_ALIGN_ADDRESS (p, alignment);
404
405                /* a may now be == end */
406                if (a > end)
407                  return DBUS_INVALID_NOT_ENOUGH_DATA;
408
409                while (p != a)
410                  {
411                    if (*p != '\0')
412                      return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
413                    ++p;
414                  }
415              }
416
417            if (claimed_len > (unsigned long) (end - p))
418              return DBUS_INVALID_LENGTH_OUT_OF_BOUNDS;
419
420            if (current_type == DBUS_TYPE_OBJECT_PATH)
421              {
422                DBusString str;
423                _dbus_string_init_const_len (&str, p, claimed_len);
424                if (!_dbus_validate_path (&str, 0,
425                                          _dbus_string_get_length (&str)))
426                  return DBUS_INVALID_BAD_PATH;
427
428                p += claimed_len;
429              }
430            else if (current_type == DBUS_TYPE_STRING)
431              {
432                DBusString str;
433                _dbus_string_init_const_len (&str, p, claimed_len);
434                if (!_dbus_string_validate_utf8 (&str, 0,
435                                                 _dbus_string_get_length (&str)))
436                  return DBUS_INVALID_BAD_UTF8_IN_STRING;
437
438                p += claimed_len;
439              }
440            else if (current_type == DBUS_TYPE_ARRAY && claimed_len > 0)
441              {
442                DBusTypeReader sub;
443                DBusValidity validity;
444                const unsigned char *array_end;
445                int array_elem_type;
446
447                if (claimed_len > DBUS_MAXIMUM_ARRAY_LENGTH)
448                  return DBUS_INVALID_ARRAY_LENGTH_EXCEEDS_MAXIMUM;
449
450                /* Remember that the reader is types only, so we can't
451                 * use it to iterate over elements. It stays the same
452                 * for all elements.
453                 */
454                _dbus_type_reader_recurse (reader, &sub);
455
456                array_end = p + claimed_len;
457
458                array_elem_type = _dbus_type_reader_get_element_type (reader);
459
460                /* avoid recursive call to validate_body_helper if this is an array
461                 * of fixed-size elements
462                 */
463                if (dbus_type_is_fixed (array_elem_type))
464                  {
465                    /* bools need to be handled differently, because they can
466                     * have an invalid value
467                     */
468                    if (array_elem_type == DBUS_TYPE_BOOLEAN)
469                      {
470                        dbus_uint32_t v;
471                        alignment = _dbus_type_get_alignment (array_elem_type);
472
473                        while (p < array_end)
474                          {
475                            v = _dbus_unpack_uint32 (byte_order, p);
476
477                            if (!(v == 0 || v == 1))
478                              return DBUS_INVALID_BOOLEAN_NOT_ZERO_OR_ONE;
479
480                            p += alignment;
481                          }
482                      }
483
484                    else
485                      {
486                        p = array_end;
487                      }
488                  }
489
490                else
491                  {
492                    while (p < array_end)
493                      {
494                        validity = validate_body_helper (&sub, byte_order, FALSE,
495                                                         total_depth + 1,
496                                                         p, end, &p);
497                        if (validity != DBUS_VALID)
498                          return validity;
499                      }
500                  }
501
502                if (p != array_end)
503                  return DBUS_INVALID_ARRAY_LENGTH_INCORRECT;
504              }
505
506            /* check nul termination */
507            if (current_type != DBUS_TYPE_ARRAY)
508              {
509                if (p == end)
510                  return DBUS_INVALID_NOT_ENOUGH_DATA;
511
512                if (*p != '\0')
513                  return DBUS_INVALID_STRING_MISSING_NUL;
514                ++p;
515              }
516          }
517          break;
518
519        case DBUS_TYPE_SIGNATURE:
520          {
521            dbus_uint32_t claimed_len;
522            DBusString str;
523            DBusValidity validity;
524
525            claimed_len = *p;
526            ++p;
527
528            /* 1 is for nul termination */
529            if (claimed_len + 1 > (unsigned long) (end - p))
530              return DBUS_INVALID_SIGNATURE_LENGTH_OUT_OF_BOUNDS;
531
532            _dbus_string_init_const_len (&str, p, claimed_len);
533            validity =
534              _dbus_validate_signature_with_reason (&str, 0,
535                                                    _dbus_string_get_length (&str));
536
537            if (validity != DBUS_VALID)
538              return validity;
539
540            p += claimed_len;
541
542            _dbus_assert (p < end);
543            if (*p != DBUS_TYPE_INVALID)
544              return DBUS_INVALID_SIGNATURE_MISSING_NUL;
545
546            ++p;
547
548            _dbus_verbose ("p = %p end = %p claimed_len %u\n", p, end, claimed_len);
549          }
550          break;
551
552        case DBUS_TYPE_VARIANT:
553          {
554            /* 1 byte sig len, sig typecodes, align to
555             * contained-type-boundary, values.
556             */
557
558            /* In addition to normal signature validation, we need to be sure
559             * the signature contains only a single (possibly container) type.
560             */
561            dbus_uint32_t claimed_len;
562            DBusString sig;
563            DBusTypeReader sub;
564            DBusValidity validity;
565            int contained_alignment;
566            int contained_type;
567            DBusValidity reason;
568
569            claimed_len = *p;
570            ++p;
571
572            /* + 1 for nul */
573            if (claimed_len + 1 > (unsigned long) (end - p))
574              return DBUS_INVALID_VARIANT_SIGNATURE_LENGTH_OUT_OF_BOUNDS;
575
576            _dbus_string_init_const_len (&sig, p, claimed_len);
577            reason = _dbus_validate_signature_with_reason (&sig, 0,
578                                           _dbus_string_get_length (&sig));
579            if (!(reason == DBUS_VALID))
580              {
581                if (reason == DBUS_VALIDITY_UNKNOWN_OOM_ERROR)
582                  return reason;
583                else
584                  return DBUS_INVALID_VARIANT_SIGNATURE_BAD;
585              }
586
587            p += claimed_len;
588
589            if (*p != DBUS_TYPE_INVALID)
590              return DBUS_INVALID_VARIANT_SIGNATURE_MISSING_NUL;
591            ++p;
592
593            contained_type = _dbus_first_type_in_signature (&sig, 0);
594            if (contained_type == DBUS_TYPE_INVALID)
595              return DBUS_INVALID_VARIANT_SIGNATURE_EMPTY;
596
597            contained_alignment = _dbus_type_get_alignment (contained_type);
598
599            a = _DBUS_ALIGN_ADDRESS (p, contained_alignment);
600            if (a > end)
601              return DBUS_INVALID_NOT_ENOUGH_DATA;
602            while (p != a)
603              {
604                if (*p != '\0')
605                  return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
606                ++p;
607              }
608
609            _dbus_type_reader_init_types_only (&sub, &sig, 0);
610
611            _dbus_assert (_dbus_type_reader_get_current_type (&sub) != DBUS_TYPE_INVALID);
612
613            validity = validate_body_helper (&sub, byte_order, FALSE,
614                                             total_depth + 1,
615                                             p, end, &p);
616            if (validity != DBUS_VALID)
617              return validity;
618
619            if (_dbus_type_reader_next (&sub))
620              return DBUS_INVALID_VARIANT_SIGNATURE_SPECIFIES_MULTIPLE_VALUES;
621
622            _dbus_assert (_dbus_type_reader_get_current_type (&sub) == DBUS_TYPE_INVALID);
623          }
624          break;
625
626        case DBUS_TYPE_DICT_ENTRY:
627        case DBUS_TYPE_STRUCT:
628          {
629            DBusTypeReader sub;
630            DBusValidity validity;
631
632            a = _DBUS_ALIGN_ADDRESS (p, 8);
633            if (a > end)
634              return DBUS_INVALID_NOT_ENOUGH_DATA;
635            while (p != a)
636              {
637                if (*p != '\0')
638                  return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
639                ++p;
640              }
641
642            _dbus_type_reader_recurse (reader, &sub);
643
644            validity = validate_body_helper (&sub, byte_order, TRUE,
645                                             total_depth + 1,
646                                             p, end, &p);
647            if (validity != DBUS_VALID)
648              return validity;
649          }
650          break;
651
652        default:
653          _dbus_assert_not_reached ("invalid typecode in supposedly-validated signature");
654          break;
655        }
656
657#if 0
658      _dbus_verbose ("   validated value of type %s type reader %p type_pos %d p %p end %p %d remain\n",
659                     _dbus_type_to_string (current_type), reader, reader->type_pos, p, end,
660                     (int) (end - p));
661#endif
662
663      if (p > end)
664        {
665          _dbus_verbose ("not enough data!!! p = %p end = %p end-p = %d\n",
666                         p, end, (int) (end - p));
667          return DBUS_INVALID_NOT_ENOUGH_DATA;
668        }
669
670      if (walk_reader_to_end)
671        _dbus_type_reader_next (reader);
672      else
673        break;
674    }
675
676  if (new_p)
677    *new_p = p;
678
679  return DBUS_VALID;
680}
681
682/**
683 * Verifies that the range of value_str from value_pos to value_end is
684 * a legitimate value of type expected_signature.  If this function
685 * returns #TRUE, it will be safe to iterate over the values with
686 * #DBusTypeReader. The signature is assumed to be already valid.
687 *
688 * If bytes_remaining is not #NULL, then leftover bytes will be stored
689 * there and #DBUS_VALID returned. If it is #NULL, then
690 * #DBUS_INVALID_TOO_MUCH_DATA will be returned if bytes are left
691 * over.
692 *
693 * @param expected_signature the expected types in the value_str
694 * @param expected_signature_start where in expected_signature is the signature
695 * @param byte_order the byte order
696 * @param bytes_remaining place to store leftover bytes
697 * @param value_str the string containing the body
698 * @param value_pos where the values start
699 * @param len length of values after value_pos
700 * @returns #DBUS_VALID if valid, reason why invalid otherwise
701 */
702DBusValidity
703_dbus_validate_body_with_reason (const DBusString *expected_signature,
704                                 int               expected_signature_start,
705                                 int               byte_order,
706                                 int              *bytes_remaining,
707                                 const DBusString *value_str,
708                                 int               value_pos,
709                                 int               len)
710{
711  DBusTypeReader reader;
712  const unsigned char *p;
713  const unsigned char *end;
714  DBusValidity validity;
715
716  _dbus_assert (len >= 0);
717  _dbus_assert (value_pos >= 0);
718  _dbus_assert (value_pos <= _dbus_string_get_length (value_str) - len);
719
720  _dbus_verbose ("validating body from pos %d len %d sig '%s'\n",
721                 value_pos, len, _dbus_string_get_const_data_len (expected_signature,
722                                                                  expected_signature_start,
723                                                                  0));
724
725  _dbus_type_reader_init_types_only (&reader,
726                                     expected_signature, expected_signature_start);
727
728  p = _dbus_string_get_const_data_len (value_str, value_pos, len);
729  end = p + len;
730
731  validity = validate_body_helper (&reader, byte_order, TRUE, 0, p, end, &p);
732  if (validity != DBUS_VALID)
733    return validity;
734
735  if (bytes_remaining)
736    {
737      *bytes_remaining = end - p;
738      return DBUS_VALID;
739    }
740  else if (p < end)
741    return DBUS_INVALID_TOO_MUCH_DATA;
742  else
743    {
744      _dbus_assert (p == end);
745      return DBUS_VALID;
746    }
747}
748
749/**
750 * Determine wether the given character is valid as the first character
751 * in a name.
752 */
753#define VALID_INITIAL_NAME_CHARACTER(c)         \
754  ( ((c) >= 'A' && (c) <= 'Z') ||               \
755    ((c) >= 'a' && (c) <= 'z') ||               \
756    ((c) == '_') )
757
758/**
759 * Determine wether the given character is valid as a second or later
760 * character in a name
761 */
762#define VALID_NAME_CHARACTER(c)                 \
763  ( ((c) >= '0' && (c) <= '9') ||               \
764    ((c) >= 'A' && (c) <= 'Z') ||               \
765    ((c) >= 'a' && (c) <= 'z') ||               \
766    ((c) == '_') )
767
768/**
769 * Checks that the given range of the string is a valid object path
770 * name in the D-Bus protocol. Part of the validation ensures that
771 * the object path contains only ASCII.
772 *
773 * @todo this is inconsistent with most of DBusString in that
774 * it allows a start,len range that extends past the string end.
775 *
776 * @todo change spec to disallow more things, such as spaces in the
777 * path name
778 *
779 * @param str the string
780 * @param start first byte index to check
781 * @param len number of bytes to check
782 * @returns #TRUE if the byte range exists and is a valid name
783 */
784dbus_bool_t
785_dbus_validate_path (const DBusString  *str,
786                     int                start,
787                     int                len)
788{
789  const unsigned char *s;
790  const unsigned char *end;
791  const unsigned char *last_slash;
792
793  _dbus_assert (start >= 0);
794  _dbus_assert (len >= 0);
795  _dbus_assert (start <= _dbus_string_get_length (str));
796
797  if (len > _dbus_string_get_length (str) - start)
798    return FALSE;
799
800  if (len == 0)
801    return FALSE;
802
803  s = _dbus_string_get_const_data (str) + start;
804  end = s + len;
805
806  if (*s != '/')
807    return FALSE;
808  last_slash = s;
809  ++s;
810
811  while (s != end)
812    {
813      if (*s == '/')
814        {
815          if ((s - last_slash) < 2)
816            return FALSE; /* no empty path components allowed */
817
818          last_slash = s;
819        }
820      else
821        {
822          if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*s)))
823            return FALSE;
824        }
825
826      ++s;
827    }
828
829  if ((end - last_slash) < 2 &&
830      len > 1)
831    return FALSE; /* trailing slash not allowed unless the string is "/" */
832
833  return TRUE;
834}
835
836const char *
837_dbus_validity_to_error_message (DBusValidity validity)
838{
839  switch (validity)
840    {
841    case DBUS_VALIDITY_UNKNOWN_OOM_ERROR:                          return "Out of memory";
842    case DBUS_INVALID_FOR_UNKNOWN_REASON:                          return "Unknown reason";
843    case DBUS_VALID_BUT_INCOMPLETE:                                return "Valid but incomplete";
844    case DBUS_VALIDITY_UNKNOWN:                                    return "Validity unknown";
845    case DBUS_VALID:                                               return "Valid";
846    case DBUS_INVALID_UNKNOWN_TYPECODE:                            return "Unknown typecode";
847    case DBUS_INVALID_MISSING_ARRAY_ELEMENT_TYPE:                  return "Missing array element type";
848    case DBUS_INVALID_SIGNATURE_TOO_LONG:                          return "Signature is too long";
849    case DBUS_INVALID_EXCEEDED_MAXIMUM_ARRAY_RECURSION:            return "Exceeded maximum array recursion";
850    case DBUS_INVALID_EXCEEDED_MAXIMUM_STRUCT_RECURSION:           return "Exceeded maximum struct recursion";
851    case DBUS_INVALID_STRUCT_ENDED_BUT_NOT_STARTED:                return "Struct ended but not started";
852    case DBUS_INVALID_STRUCT_STARTED_BUT_NOT_ENDED:                return "Struct started but not ended";
853    case DBUS_INVALID_STRUCT_HAS_NO_FIELDS:                        return "Struct has no fields";
854    case DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL:                   return "Alignment padding not null";
855    case DBUS_INVALID_BOOLEAN_NOT_ZERO_OR_ONE:                     return "Boolean is not zero or one";
856    case DBUS_INVALID_NOT_ENOUGH_DATA:                             return "Not enough data";
857    case DBUS_INVALID_TOO_MUCH_DATA:                               return "Too much data";
858    case DBUS_INVALID_BAD_BYTE_ORDER:                              return "Bad byte order";
859    case DBUS_INVALID_BAD_PROTOCOL_VERSION:                        return "Bad protocol version";
860    case DBUS_INVALID_BAD_MESSAGE_TYPE:                            return "Bad message type";
861    case DBUS_INVALID_BAD_SERIAL:                                  return "Bad serial";
862    case DBUS_INVALID_INSANE_FIELDS_ARRAY_LENGTH:                  return "Insane fields array length";
863    case DBUS_INVALID_INSANE_BODY_LENGTH:                          return "Insane body length";
864    case DBUS_INVALID_MESSAGE_TOO_LONG:                            return "Message too long";
865    case DBUS_INVALID_HEADER_FIELD_CODE:                           return "Header field code";
866    case DBUS_INVALID_HEADER_FIELD_HAS_WRONG_TYPE:                 return "Header field has wrong type";
867    case DBUS_INVALID_USES_LOCAL_INTERFACE:                        return "Uses local interface";
868    case DBUS_INVALID_USES_LOCAL_PATH:                             return "Uses local path";
869    case DBUS_INVALID_HEADER_FIELD_APPEARS_TWICE:                  return "Header field appears twice";
870    case DBUS_INVALID_BAD_DESTINATION:                             return "Bad destination";
871    case DBUS_INVALID_BAD_INTERFACE:                               return "Bad interface";
872    case DBUS_INVALID_BAD_MEMBER:                                  return "Bad member";
873    case DBUS_INVALID_BAD_ERROR_NAME:                              return "Bad error name";
874    case DBUS_INVALID_BAD_SENDER:                                  return "Bad sender";
875    case DBUS_INVALID_MISSING_PATH:                                return "Missing path";
876    case DBUS_INVALID_MISSING_INTERFACE:                           return "Missing interface";
877    case DBUS_INVALID_MISSING_MEMBER:                              return "Missing member";
878    case DBUS_INVALID_MISSING_ERROR_NAME:                          return "Missing error name";
879    case DBUS_INVALID_MISSING_REPLY_SERIAL:                        return "Missing reply serial";
880    case DBUS_INVALID_LENGTH_OUT_OF_BOUNDS:                        return "Length out of bounds";
881    case DBUS_INVALID_ARRAY_LENGTH_EXCEEDS_MAXIMUM:                return "Array length exceeds maximum";
882    case DBUS_INVALID_BAD_PATH:                                    return "Bad path";
883    case DBUS_INVALID_SIGNATURE_LENGTH_OUT_OF_BOUNDS:              return "Signature length out of bounds";
884    case DBUS_INVALID_BAD_UTF8_IN_STRING:                          return "Bad utf8 in string";
885    case DBUS_INVALID_ARRAY_LENGTH_INCORRECT:                      return "Array length incorrect";
886    case DBUS_INVALID_VARIANT_SIGNATURE_LENGTH_OUT_OF_BOUNDS:      return "Variant signature length out of bounds";
887    case DBUS_INVALID_VARIANT_SIGNATURE_BAD:                       return "Variant signature bad";
888    case DBUS_INVALID_VARIANT_SIGNATURE_EMPTY:                     return "Variant signature empty";
889    case DBUS_INVALID_VARIANT_SIGNATURE_SPECIFIES_MULTIPLE_VALUES: return "Variant signature specifies multiple values";
890    case DBUS_INVALID_VARIANT_SIGNATURE_MISSING_NUL:               return "Variant signature missing nul";
891    case DBUS_INVALID_STRING_MISSING_NUL:                          return "String missing nul";
892    case DBUS_INVALID_SIGNATURE_MISSING_NUL:                       return "Signature missing nul";
893    case DBUS_INVALID_EXCEEDED_MAXIMUM_DICT_ENTRY_RECURSION:       return "Exceeded maximum dict entry recursion";
894    case DBUS_INVALID_DICT_ENTRY_ENDED_BUT_NOT_STARTED:            return "Dict entry ended but not started";
895    case DBUS_INVALID_DICT_ENTRY_STARTED_BUT_NOT_ENDED:            return "Dict entry started but not ended";
896    case DBUS_INVALID_DICT_ENTRY_HAS_NO_FIELDS:                    return "Dict entry has no fields";
897    case DBUS_INVALID_DICT_ENTRY_HAS_ONLY_ONE_FIELD:               return "Dict entry has only one field";
898    case DBUS_INVALID_DICT_ENTRY_HAS_TOO_MANY_FIELDS:              return "Dict entry has too many fields";
899    case DBUS_INVALID_DICT_ENTRY_NOT_INSIDE_ARRAY:                 return "Dict entry not inside array";
900    case DBUS_INVALID_DICT_KEY_MUST_BE_BASIC_TYPE:                 return "Dict key must be basic type";
901    case DBUS_INVALID_NESTED_TOO_DEEPLY:                           return "Variants cannot be used to create a hugely recursive tree of values";
902    default:
903      return "Invalid";
904    }
905}
906
907/**
908 * Checks that the given range of the string is a valid interface name
909 * in the D-Bus protocol. This includes a length restriction and an
910 * ASCII subset, see the specification.
911 *
912 * @todo this is inconsistent with most of DBusString in that
913 * it allows a start,len range that extends past the string end.
914 *
915 * @param str the string
916 * @param start first byte index to check
917 * @param len number of bytes to check
918 * @returns #TRUE if the byte range exists and is a valid name
919 */
920dbus_bool_t
921_dbus_validate_interface (const DBusString  *str,
922                          int                start,
923                          int                len)
924{
925  const unsigned char *s;
926  const unsigned char *end;
927  const unsigned char *iface;
928  const unsigned char *last_dot;
929
930  _dbus_assert (start >= 0);
931  _dbus_assert (len >= 0);
932  _dbus_assert (start <= _dbus_string_get_length (str));
933
934  if (len > _dbus_string_get_length (str) - start)
935    return FALSE;
936
937  if (len > DBUS_MAXIMUM_NAME_LENGTH)
938    return FALSE;
939
940  if (len == 0)
941    return FALSE;
942
943  last_dot = NULL;
944  iface = _dbus_string_get_const_data (str) + start;
945  end = iface + len;
946  s = iface;
947
948  /* check special cases of first char so it doesn't have to be done
949   * in the loop. Note we know len > 0
950   */
951  if (_DBUS_UNLIKELY (*s == '.')) /* disallow starting with a . */
952    return FALSE;
953  else if (_DBUS_UNLIKELY (!VALID_INITIAL_NAME_CHARACTER (*s)))
954    return FALSE;
955  else
956    ++s;
957
958  while (s != end)
959    {
960      if (*s == '.')
961        {
962          if (_DBUS_UNLIKELY ((s + 1) == end))
963            return FALSE;
964          else if (_DBUS_UNLIKELY (!VALID_INITIAL_NAME_CHARACTER (*(s + 1))))
965            return FALSE;
966          last_dot = s;
967          ++s; /* we just validated the next char, so skip two */
968        }
969      else if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*s)))
970        {
971          return FALSE;
972        }
973
974      ++s;
975    }
976
977  if (_DBUS_UNLIKELY (last_dot == NULL))
978    return FALSE;
979
980  return TRUE;
981}
982
983/**
984 * Checks that the given range of the string is a valid member name
985 * in the D-Bus protocol. This includes a length restriction, etc.,
986 * see the specification.
987 *
988 * @todo this is inconsistent with most of DBusString in that
989 * it allows a start,len range that extends past the string end.
990 *
991 * @param str the string
992 * @param start first byte index to check
993 * @param len number of bytes to check
994 * @returns #TRUE if the byte range exists and is a valid name
995 */
996dbus_bool_t
997_dbus_validate_member (const DBusString  *str,
998                       int                start,
999                       int                len)
1000{
1001  const unsigned char *s;
1002  const unsigned char *end;
1003  const unsigned char *member;
1004
1005  _dbus_assert (start >= 0);
1006  _dbus_assert (len >= 0);
1007  _dbus_assert (start <= _dbus_string_get_length (str));
1008
1009  if (len > _dbus_string_get_length (str) - start)
1010    return FALSE;
1011
1012  if (len > DBUS_MAXIMUM_NAME_LENGTH)
1013    return FALSE;
1014
1015  if (len == 0)
1016    return FALSE;
1017
1018  member = _dbus_string_get_const_data (str) + start;
1019  end = member + len;
1020  s = member;
1021
1022  /* check special cases of first char so it doesn't have to be done
1023   * in the loop. Note we know len > 0
1024   */
1025
1026  if (_DBUS_UNLIKELY (!VALID_INITIAL_NAME_CHARACTER (*s)))
1027    return FALSE;
1028  else
1029    ++s;
1030
1031  while (s != end)
1032    {
1033      if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*s)))
1034        {
1035          return FALSE;
1036        }
1037
1038      ++s;
1039    }
1040
1041  return TRUE;
1042}
1043
1044/**
1045 * Checks that the given range of the string is a valid error name
1046 * in the D-Bus protocol. This includes a length restriction, etc.,
1047 * see the specification.
1048 *
1049 * @todo this is inconsistent with most of DBusString in that
1050 * it allows a start,len range that extends past the string end.
1051 *
1052 * @param str the string
1053 * @param start first byte index to check
1054 * @param len number of bytes to check
1055 * @returns #TRUE if the byte range exists and is a valid name
1056 */
1057dbus_bool_t
1058_dbus_validate_error_name (const DBusString  *str,
1059                           int                start,
1060                           int                len)
1061{
1062  /* Same restrictions as interface name at the moment */
1063  return _dbus_validate_interface (str, start, len);
1064}
1065
1066/**
1067 * Determine wether the given character is valid as the first character
1068 * in a bus name.
1069 */
1070#define VALID_INITIAL_BUS_NAME_CHARACTER(c)         \
1071  ( ((c) >= 'A' && (c) <= 'Z') ||               \
1072    ((c) >= 'a' && (c) <= 'z') ||               \
1073    ((c) == '_') || ((c) == '-'))
1074
1075/**
1076 * Determine wether the given character is valid as a second or later
1077 * character in a bus name
1078 */
1079#define VALID_BUS_NAME_CHARACTER(c)                 \
1080  ( ((c) >= '0' && (c) <= '9') ||               \
1081    ((c) >= 'A' && (c) <= 'Z') ||               \
1082    ((c) >= 'a' && (c) <= 'z') ||               \
1083    ((c) == '_') || ((c) == '-'))
1084
1085/**
1086 * Checks that the given range of the string is a valid bus name in
1087 * the D-Bus protocol. This includes a length restriction, etc., see
1088 * the specification.
1089 *
1090 * @todo this is inconsistent with most of DBusString in that
1091 * it allows a start,len range that extends past the string end.
1092 *
1093 * @param str the string
1094 * @param start first byte index to check
1095 * @param len number of bytes to check
1096 * @returns #TRUE if the byte range exists and is a valid name
1097 */
1098dbus_bool_t
1099_dbus_validate_bus_name (const DBusString  *str,
1100                         int                start,
1101                         int                len)
1102{
1103  const unsigned char *s;
1104  const unsigned char *end;
1105  const unsigned char *iface;
1106  const unsigned char *last_dot;
1107
1108  _dbus_assert (start >= 0);
1109  _dbus_assert (len >= 0);
1110  _dbus_assert (start <= _dbus_string_get_length (str));
1111
1112  if (len > _dbus_string_get_length (str) - start)
1113    return FALSE;
1114
1115  if (len > DBUS_MAXIMUM_NAME_LENGTH)
1116    return FALSE;
1117
1118  if (len == 0)
1119    return FALSE;
1120
1121  last_dot = NULL;
1122  iface = _dbus_string_get_const_data (str) + start;
1123  end = iface + len;
1124  s = iface;
1125
1126  /* check special cases of first char so it doesn't have to be done
1127   * in the loop. Note we know len > 0
1128   */
1129  if (*s == ':')
1130  {
1131    /* unique name */
1132    ++s;
1133    while (s != end)
1134      {
1135        if (*s == '.')
1136          {
1137            if (_DBUS_UNLIKELY ((s + 1) == end))
1138              return FALSE;
1139            if (_DBUS_UNLIKELY (!VALID_BUS_NAME_CHARACTER (*(s + 1))))
1140              return FALSE;
1141            ++s; /* we just validated the next char, so skip two */
1142          }
1143        else if (_DBUS_UNLIKELY (!VALID_BUS_NAME_CHARACTER (*s)))
1144          {
1145            return FALSE;
1146          }
1147
1148        ++s;
1149      }
1150
1151    return TRUE;
1152  }
1153  else if (_DBUS_UNLIKELY (*s == '.')) /* disallow starting with a . */
1154    return FALSE;
1155  else if (_DBUS_UNLIKELY (!VALID_INITIAL_BUS_NAME_CHARACTER (*s)))
1156    return FALSE;
1157  else
1158    ++s;
1159
1160  while (s != end)
1161    {
1162      if (*s == '.')
1163        {
1164          if (_DBUS_UNLIKELY ((s + 1) == end))
1165            return FALSE;
1166          else if (_DBUS_UNLIKELY (!VALID_INITIAL_BUS_NAME_CHARACTER (*(s + 1))))
1167            return FALSE;
1168          last_dot = s;
1169          ++s; /* we just validated the next char, so skip two */
1170        }
1171      else if (_DBUS_UNLIKELY (!VALID_BUS_NAME_CHARACTER (*s)))
1172        {
1173          return FALSE;
1174        }
1175
1176      ++s;
1177    }
1178
1179  if (_DBUS_UNLIKELY (last_dot == NULL))
1180    return FALSE;
1181
1182  return TRUE;
1183}
1184
1185/**
1186 * Checks that the given range of the string is a valid message type
1187 * signature in the D-Bus protocol.
1188 *
1189 * @todo this is inconsistent with most of DBusString in that
1190 * it allows a start,len range that extends past the string end.
1191 *
1192 * @param str the string
1193 * @param start first byte index to check
1194 * @param len number of bytes to check
1195 * @returns #TRUE if the byte range exists and is a valid signature
1196 */
1197dbus_bool_t
1198_dbus_validate_signature (const DBusString  *str,
1199                          int                start,
1200                          int                len)
1201{
1202  _dbus_assert (start >= 0);
1203  _dbus_assert (start <= _dbus_string_get_length (str));
1204  _dbus_assert (len >= 0);
1205
1206  if (len > _dbus_string_get_length (str) - start)
1207    return FALSE;
1208
1209  return _dbus_validate_signature_with_reason (str, start, len) == DBUS_VALID;
1210}
1211
1212/** define _dbus_check_is_valid_path() */
1213DEFINE_DBUS_NAME_CHECK(path)
1214/** define _dbus_check_is_valid_interface() */
1215DEFINE_DBUS_NAME_CHECK(interface)
1216/** define _dbus_check_is_valid_member() */
1217DEFINE_DBUS_NAME_CHECK(member)
1218/** define _dbus_check_is_valid_error_name() */
1219DEFINE_DBUS_NAME_CHECK(error_name)
1220/** define _dbus_check_is_valid_bus_name() */
1221DEFINE_DBUS_NAME_CHECK(bus_name)
1222/** define _dbus_check_is_valid_signature() */
1223DEFINE_DBUS_NAME_CHECK(signature)
1224
1225/** @} */
1226
1227/* tests in dbus-marshal-validate-util.c */
1228