1 /* -*- mode: C; c-file-style: "gnu" -*- */
2 /* dbus-marshal-validate.c Validation routines for marshaled data
4 * Copyright (C) 2005 Red Hat, Inc.
6 * Licensed under the Academic Free License version 2.1
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.
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.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include "dbus-internals.h"
25 #include "dbus-marshal-validate.h"
26 #include "dbus-marshal-recursive.h"
27 #include "dbus-marshal-basic.h"
28 #include "dbus-string.h"
31 * @addtogroup DBusMarshal
37 * Verifies that the range of type_str from type_pos to type_end is a
38 * valid signature. If this function returns #TRUE, it will be safe
39 * to iterate over the signature with a types-only #DBusTypeReader.
40 * The range passed in should NOT include the terminating
41 * nul/DBUS_TYPE_INVALID.
43 * @todo verify that dict entries have exactly two fields
45 * @todo require that dict entries are in an array
47 * @param type_str the string
48 * @param type_pos where the typecodes start
49 * @param len length of typecodes
50 * @returns #DBUS_VALID if valid, reason why invalid otherwise
53 _dbus_validate_signature_with_reason (const DBusString *type_str,
57 const unsigned char *p;
58 const unsigned char *end;
64 _dbus_assert (type_str != NULL);
65 _dbus_assert (type_pos < _DBUS_INT32_MAX - len);
66 _dbus_assert (len >= 0);
67 _dbus_assert (type_pos >= 0);
69 if (len > DBUS_MAXIMUM_SIGNATURE_LENGTH)
70 return DBUS_INVALID_SIGNATURE_TOO_LONG;
72 p = _dbus_string_get_const_data_len (type_str, type_pos, 0);
73 end = _dbus_string_get_const_data_len (type_str, type_pos + len, 0);
77 last = DBUS_TYPE_INVALID;
84 case DBUS_TYPE_BOOLEAN:
86 case DBUS_TYPE_UINT16:
88 case DBUS_TYPE_UINT32:
90 case DBUS_TYPE_UINT64:
91 case DBUS_TYPE_DOUBLE:
92 case DBUS_TYPE_STRING:
93 case DBUS_TYPE_OBJECT_PATH:
94 case DBUS_TYPE_SIGNATURE:
95 case DBUS_TYPE_VARIANT:
100 if (array_depth > DBUS_MAXIMUM_TYPE_RECURSION_DEPTH)
101 return DBUS_INVALID_EXCEEDED_MAXIMUM_ARRAY_RECURSION;
104 case DBUS_STRUCT_BEGIN_CHAR:
107 if (struct_depth > DBUS_MAXIMUM_TYPE_RECURSION_DEPTH)
108 return DBUS_INVALID_EXCEEDED_MAXIMUM_STRUCT_RECURSION;
111 case DBUS_STRUCT_END_CHAR:
112 if (struct_depth == 0)
113 return DBUS_INVALID_STRUCT_ENDED_BUT_NOT_STARTED;
115 if (last == DBUS_STRUCT_BEGIN_CHAR)
116 return DBUS_INVALID_STRUCT_HAS_NO_FIELDS;
121 case DBUS_DICT_ENTRY_BEGIN_CHAR:
122 if (last != DBUS_TYPE_ARRAY)
123 return DBUS_INVALID_DICT_ENTRY_NOT_INSIDE_ARRAY;
125 dict_entry_depth += 1;
127 if (dict_entry_depth > DBUS_MAXIMUM_TYPE_RECURSION_DEPTH)
128 return DBUS_INVALID_EXCEEDED_MAXIMUM_DICT_ENTRY_RECURSION;
131 case DBUS_DICT_ENTRY_END_CHAR:
132 if (dict_entry_depth == 0)
133 return DBUS_INVALID_DICT_ENTRY_ENDED_BUT_NOT_STARTED;
135 if (last == DBUS_DICT_ENTRY_BEGIN_CHAR)
136 return DBUS_INVALID_DICT_ENTRY_HAS_NO_FIELDS;
138 dict_entry_depth -= 1;
141 case DBUS_TYPE_STRUCT: /* doesn't appear in signatures */
142 case DBUS_TYPE_DICT_ENTRY: /* ditto */
144 return DBUS_INVALID_UNKNOWN_TYPECODE;
147 if (*p != DBUS_TYPE_ARRAY)
155 return DBUS_INVALID_MISSING_ARRAY_ELEMENT_TYPE;
157 if (struct_depth > 0)
158 return DBUS_INVALID_STRUCT_STARTED_BUT_NOT_ENDED;
160 if (dict_entry_depth > 0)
161 return DBUS_INVALID_DICT_ENTRY_STARTED_BUT_NOT_ENDED;
167 validate_body_helper (DBusTypeReader *reader,
169 dbus_bool_t walk_reader_to_end,
170 const unsigned char *p,
171 const unsigned char *end,
172 const unsigned char **new_p)
176 while ((current_type = _dbus_type_reader_get_current_type (reader)) != DBUS_TYPE_INVALID)
178 const unsigned char *a;
182 _dbus_verbose (" validating value of type %s type reader %p type_pos %d p %p end %p %d remain\n",
183 _dbus_type_to_string (current_type), reader, reader->type_pos, p, end,
187 /* Guarantee that p has one byte to look at */
189 return DBUS_INVALID_NOT_ENOUGH_DATA;
191 switch (current_type)
197 case DBUS_TYPE_BOOLEAN:
198 case DBUS_TYPE_INT16:
199 case DBUS_TYPE_UINT16:
200 case DBUS_TYPE_INT32:
201 case DBUS_TYPE_UINT32:
202 case DBUS_TYPE_INT64:
203 case DBUS_TYPE_UINT64:
204 case DBUS_TYPE_DOUBLE:
205 alignment = _dbus_type_get_alignment (current_type);
206 a = _DBUS_ALIGN_ADDRESS (p, alignment);
208 return DBUS_INVALID_NOT_ENOUGH_DATA;
212 return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
216 if (current_type == DBUS_TYPE_BOOLEAN)
218 dbus_uint32_t v = _dbus_unpack_uint32 (byte_order,
220 if (!(v == 0 || v == 1))
221 return DBUS_INVALID_BOOLEAN_NOT_ZERO_OR_ONE;
227 case DBUS_TYPE_ARRAY:
228 case DBUS_TYPE_STRING:
229 case DBUS_TYPE_OBJECT_PATH:
231 dbus_uint32_t claimed_len;
233 a = _DBUS_ALIGN_ADDRESS (p, 4);
235 return DBUS_INVALID_NOT_ENOUGH_DATA;
239 return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
243 claimed_len = _dbus_unpack_uint32 (byte_order, p);
246 /* p may now be == end */
247 _dbus_assert (p <= end);
249 if (current_type == DBUS_TYPE_ARRAY)
251 int array_elem_type = _dbus_type_reader_get_element_type (reader);
252 alignment = _dbus_type_get_alignment (array_elem_type);
253 p = _DBUS_ALIGN_ADDRESS (p, alignment);
256 if (claimed_len > (unsigned long) (end - p))
257 return DBUS_INVALID_STRING_LENGTH_OUT_OF_BOUNDS;
259 if (current_type == DBUS_TYPE_OBJECT_PATH)
262 _dbus_string_init_const_len (&str, p, claimed_len);
263 if (!_dbus_validate_path (&str, 0,
264 _dbus_string_get_length (&str)))
265 return DBUS_INVALID_BAD_PATH;
269 else if (current_type == DBUS_TYPE_STRING)
272 _dbus_string_init_const_len (&str, p, claimed_len);
273 if (!_dbus_string_validate_utf8 (&str, 0,
274 _dbus_string_get_length (&str)))
275 return DBUS_INVALID_BAD_UTF8_IN_STRING;
279 else if (current_type == DBUS_TYPE_ARRAY && claimed_len > 0)
282 DBusValidity validity;
283 const unsigned char *array_end;
285 /* Remember that the reader is types only, so we can't
286 * use it to iterate over elements. It stays the same
289 _dbus_type_reader_recurse (reader, &sub);
291 array_end = p + claimed_len;
293 while (p < array_end)
295 /* FIXME we are calling a function per array element! very bad
296 * need if (dbus_type_is_fixed(elem_type)) here to just skip
297 * big blocks of ints/bytes/etc.
300 validity = validate_body_helper (&sub, byte_order, FALSE, p, end, &p);
301 if (validity != DBUS_VALID)
306 return DBUS_INVALID_ARRAY_LENGTH_INCORRECT;
309 /* check nul termination */
310 if (current_type != DBUS_TYPE_ARRAY)
313 return DBUS_INVALID_NOT_ENOUGH_DATA;
316 return DBUS_INVALID_STRING_MISSING_NUL;
322 case DBUS_TYPE_SIGNATURE:
324 dbus_uint32_t claimed_len;
330 /* 1 is for nul termination */
331 if (claimed_len + 1 > (unsigned long) (end - p))
332 return DBUS_INVALID_SIGNATURE_LENGTH_OUT_OF_BOUNDS;
334 _dbus_string_init_const_len (&str, p, claimed_len);
335 if (!_dbus_validate_signature (&str, 0,
336 _dbus_string_get_length (&str)))
337 return DBUS_INVALID_BAD_SIGNATURE;
341 _dbus_assert (p < end);
342 if (*p != DBUS_TYPE_INVALID)
343 return DBUS_INVALID_SIGNATURE_MISSING_NUL;
347 _dbus_verbose ("p = %p end = %p claimed_len %u\n", p, end, claimed_len);
351 case DBUS_TYPE_VARIANT:
353 /* 1 byte sig len, sig typecodes, align to
354 * contained-type-boundary, values.
357 /* In addition to normal signature validation, we need to be sure
358 * the signature contains only a single (possibly container) type.
360 dbus_uint32_t claimed_len;
363 DBusValidity validity;
364 int contained_alignment;
370 if (claimed_len + 1 > (unsigned long) (end - p))
371 return DBUS_INVALID_VARIANT_SIGNATURE_LENGTH_OUT_OF_BOUNDS;
373 _dbus_string_init_const_len (&sig, p, claimed_len);
374 if (!_dbus_validate_signature (&sig, 0,
375 _dbus_string_get_length (&sig)))
376 return DBUS_INVALID_VARIANT_SIGNATURE_BAD;
380 if (*p != DBUS_TYPE_INVALID)
381 return DBUS_INVALID_VARIANT_SIGNATURE_MISSING_NUL;
384 contained_alignment = _dbus_type_get_alignment (_dbus_first_type_in_signature (&sig, 0));
386 a = _DBUS_ALIGN_ADDRESS (p, contained_alignment);
388 return DBUS_INVALID_NOT_ENOUGH_DATA;
392 return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
396 _dbus_type_reader_init_types_only (&sub, &sig, 0);
398 if (_dbus_type_reader_get_current_type (&sub) == DBUS_TYPE_INVALID)
399 return DBUS_INVALID_VARIANT_SIGNATURE_EMPTY;
401 validity = validate_body_helper (&sub, byte_order, FALSE, p, end, &p);
402 if (validity != DBUS_VALID)
405 if (_dbus_type_reader_next (&sub))
406 return DBUS_INVALID_VARIANT_SIGNATURE_SPECIFIES_MULTIPLE_VALUES;
408 _dbus_assert (_dbus_type_reader_get_current_type (&sub) == DBUS_TYPE_INVALID);
412 case DBUS_TYPE_DICT_ENTRY:
413 case DBUS_TYPE_STRUCT:
416 DBusValidity validity;
418 a = _DBUS_ALIGN_ADDRESS (p, 8);
420 return DBUS_INVALID_NOT_ENOUGH_DATA;
424 return DBUS_INVALID_ALIGNMENT_PADDING_NOT_NUL;
428 _dbus_type_reader_recurse (reader, &sub);
430 validity = validate_body_helper (&sub, byte_order, TRUE, p, end, &p);
431 if (validity != DBUS_VALID)
437 _dbus_assert_not_reached ("invalid typecode in supposedly-validated signature");
442 _dbus_verbose (" validated value of type %s type reader %p type_pos %d p %p end %p %d remain\n",
443 _dbus_type_to_string (current_type), reader, reader->type_pos, p, end,
449 _dbus_verbose ("not enough data!!! p = %p end = %p end-p = %d\n",
450 p, end, (int) (end - p));
451 return DBUS_INVALID_NOT_ENOUGH_DATA;
454 if (walk_reader_to_end)
455 _dbus_type_reader_next (reader);
467 * Verifies that the range of value_str from value_pos to value_end is
468 * a legitimate value of type expected_signature. If this function
469 * returns #TRUE, it will be safe to iterate over the values with
470 * #DBusTypeReader. The signature is assumed to be already valid.
472 * If bytes_remaining is not #NULL, then leftover bytes will be stored
473 * there and #DBUS_VALID returned. If it is #NULL, then
474 * #DBUS_INVALID_TOO_MUCH_DATA will be returned if bytes are left
477 * @param expected_signature the expected types in the value_str
478 * @param expected_signature_start where in expected_signature is the signature
479 * @param byte_order the byte order
480 * @param bytes_remaining place to store leftover bytes
481 * @param value_str the string containing the body
482 * @param value_pos where the values start
483 * @param len length of values after value_pos
484 * @returns #DBUS_VALID if valid, reason why invalid otherwise
487 _dbus_validate_body_with_reason (const DBusString *expected_signature,
488 int expected_signature_start,
490 int *bytes_remaining,
491 const DBusString *value_str,
495 DBusTypeReader reader;
496 const unsigned char *p;
497 const unsigned char *end;
498 DBusValidity validity;
500 _dbus_assert (len >= 0);
501 _dbus_assert (value_pos >= 0);
502 _dbus_assert (value_pos <= _dbus_string_get_length (value_str) - len);
504 _dbus_verbose ("validating body from pos %d len %d sig '%s'\n",
505 value_pos, len, _dbus_string_get_const_data_len (expected_signature,
506 expected_signature_start,
509 _dbus_type_reader_init_types_only (&reader,
510 expected_signature, expected_signature_start);
512 p = _dbus_string_get_const_data_len (value_str, value_pos, len);
515 validity = validate_body_helper (&reader, byte_order, TRUE, p, end, &p);
516 if (validity != DBUS_VALID)
521 *bytes_remaining = end - p;
525 return DBUS_INVALID_TOO_MUCH_DATA;
528 _dbus_assert (p == end);
534 * Determine wether the given charater is valid as the first charater
537 #define VALID_INITIAL_NAME_CHARACTER(c) \
538 ( ((c) >= 'A' && (c) <= 'Z') || \
539 ((c) >= 'a' && (c) <= 'z') || \
543 * Determine wether the given charater is valid as a second or later
544 * character in a name
546 #define VALID_NAME_CHARACTER(c) \
547 ( ((c) >= '0' && (c) <= '9') || \
548 ((c) >= 'A' && (c) <= 'Z') || \
549 ((c) >= 'a' && (c) <= 'z') || \
553 * Checks that the given range of the string is a valid object path
554 * name in the D-BUS protocol. Part of the validation ensures that
555 * the object path contains only ASCII.
557 * @todo this is inconsistent with most of DBusString in that
558 * it allows a start,len range that extends past the string end.
560 * @todo change spec to disallow more things, such as spaces in the
563 * @param str the string
564 * @param start first byte index to check
565 * @param len number of bytes to check
566 * @returns #TRUE if the byte range exists and is a valid name
569 _dbus_validate_path (const DBusString *str,
573 const unsigned char *s;
574 const unsigned char *end;
575 const unsigned char *last_slash;
577 _dbus_assert (start >= 0);
578 _dbus_assert (len >= 0);
579 _dbus_assert (start <= _dbus_string_get_length (str));
581 if (len > _dbus_string_get_length (str) - start)
587 s = _dbus_string_get_const_data (str) + start;
599 if ((s - last_slash) < 2)
600 return FALSE; /* no empty path components allowed */
606 if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*s)))
613 if ((end - last_slash) < 2 &&
615 return FALSE; /* trailing slash not allowed unless the string is "/" */
621 * Checks that the given range of the string is a valid interface name
622 * in the D-BUS protocol. This includes a length restriction and an
623 * ASCII subset, see the specification.
625 * @todo this is inconsistent with most of DBusString in that
626 * it allows a start,len range that extends past the string end.
628 * @param str the string
629 * @param start first byte index to check
630 * @param len number of bytes to check
631 * @returns #TRUE if the byte range exists and is a valid name
634 _dbus_validate_interface (const DBusString *str,
638 const unsigned char *s;
639 const unsigned char *end;
640 const unsigned char *iface;
641 const unsigned char *last_dot;
643 _dbus_assert (start >= 0);
644 _dbus_assert (len >= 0);
645 _dbus_assert (start <= _dbus_string_get_length (str));
647 if (len > _dbus_string_get_length (str) - start)
650 if (len > DBUS_MAXIMUM_NAME_LENGTH)
657 iface = _dbus_string_get_const_data (str) + start;
661 /* check special cases of first char so it doesn't have to be done
662 * in the loop. Note we know len > 0
664 if (_DBUS_UNLIKELY (*s == '.')) /* disallow starting with a . */
666 else if (_DBUS_UNLIKELY (!VALID_INITIAL_NAME_CHARACTER (*s)))
675 if (_DBUS_UNLIKELY ((s + 1) == end))
677 else if (_DBUS_UNLIKELY (!VALID_INITIAL_NAME_CHARACTER (*(s + 1))))
680 ++s; /* we just validated the next char, so skip two */
682 else if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*s)))
690 if (_DBUS_UNLIKELY (last_dot == NULL))
697 * Checks that the given range of the string is a valid member name
698 * in the D-BUS protocol. This includes a length restriction, etc.,
699 * see the specification.
701 * @todo this is inconsistent with most of DBusString in that
702 * it allows a start,len range that extends past the string end.
704 * @param str the string
705 * @param start first byte index to check
706 * @param len number of bytes to check
707 * @returns #TRUE if the byte range exists and is a valid name
710 _dbus_validate_member (const DBusString *str,
714 const unsigned char *s;
715 const unsigned char *end;
716 const unsigned char *member;
718 _dbus_assert (start >= 0);
719 _dbus_assert (len >= 0);
720 _dbus_assert (start <= _dbus_string_get_length (str));
722 if (len > _dbus_string_get_length (str) - start)
725 if (len > DBUS_MAXIMUM_NAME_LENGTH)
731 member = _dbus_string_get_const_data (str) + start;
735 /* check special cases of first char so it doesn't have to be done
736 * in the loop. Note we know len > 0
739 if (_DBUS_UNLIKELY (!VALID_INITIAL_NAME_CHARACTER (*s)))
746 if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*s)))
758 * Checks that the given range of the string is a valid error name
759 * in the D-BUS protocol. This includes a length restriction, etc.,
760 * see the specification.
762 * @todo this is inconsistent with most of DBusString in that
763 * it allows a start,len range that extends past the string end.
765 * @param str the string
766 * @param start first byte index to check
767 * @param len number of bytes to check
768 * @returns #TRUE if the byte range exists and is a valid name
771 _dbus_validate_error_name (const DBusString *str,
775 /* Same restrictions as interface name at the moment */
776 return _dbus_validate_interface (str, start, len);
779 /* This assumes the first char exists and is ':' */
781 _dbus_validate_unique_name (const DBusString *str,
785 const unsigned char *s;
786 const unsigned char *end;
787 const unsigned char *name;
789 _dbus_assert (start >= 0);
790 _dbus_assert (len >= 0);
791 _dbus_assert (start <= _dbus_string_get_length (str));
793 if (len > _dbus_string_get_length (str) - start)
796 if (len > DBUS_MAXIMUM_NAME_LENGTH)
799 _dbus_assert (len > 0);
801 name = _dbus_string_get_const_data (str) + start;
803 _dbus_assert (*name == ':');
810 if (_DBUS_UNLIKELY ((s + 1) == end))
812 if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*(s + 1))))
814 ++s; /* we just validated the next char, so skip two */
816 else if (_DBUS_UNLIKELY (!VALID_NAME_CHARACTER (*s)))
828 * Checks that the given range of the string is a valid bus name in
829 * the D-BUS protocol. This includes a length restriction, etc., see
832 * @todo this is inconsistent with most of DBusString in that
833 * it allows a start,len range that extends past the string end.
835 * @param str the string
836 * @param start first byte index to check
837 * @param len number of bytes to check
838 * @returns #TRUE if the byte range exists and is a valid name
841 _dbus_validate_bus_name (const DBusString *str,
845 if (_DBUS_UNLIKELY (len == 0))
847 if (_dbus_string_get_byte (str, start) == ':')
848 return _dbus_validate_unique_name (str, start, len);
850 return _dbus_validate_interface (str, start, len);
854 * Checks that the given range of the string is a valid message type
855 * signature in the D-BUS protocol.
857 * @todo this is inconsistent with most of DBusString in that
858 * it allows a start,len range that extends past the string end.
860 * @param str the string
861 * @param start first byte index to check
862 * @param len number of bytes to check
863 * @returns #TRUE if the byte range exists and is a valid signature
866 _dbus_validate_signature (const DBusString *str,
870 _dbus_assert (start >= 0);
871 _dbus_assert (start <= _dbus_string_get_length (str));
872 _dbus_assert (len >= 0);
874 if (len > _dbus_string_get_length (str) - start)
877 return _dbus_validate_signature_with_reason (str, start, len) == DBUS_VALID;
880 /** define _dbus_check_is_valid_path() */
881 DEFINE_DBUS_NAME_CHECK(path);
882 /** define _dbus_check_is_valid_interface() */
883 DEFINE_DBUS_NAME_CHECK(interface);
884 /** define _dbus_check_is_valid_member() */
885 DEFINE_DBUS_NAME_CHECK(member);
886 /** define _dbus_check_is_valid_error_name() */
887 DEFINE_DBUS_NAME_CHECK(error_name);
888 /** define _dbus_check_is_valid_bus_name() */
889 DEFINE_DBUS_NAME_CHECK(bus_name);
890 /** define _dbus_check_is_valid_signature() */
891 DEFINE_DBUS_NAME_CHECK(signature);
895 /* tests in dbus-marshal-validate-util.c */