You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

252 lines
6.5 KiB

/*
* libfdt - Flat Device Tree manipulation
* Copyright (C) 2006 David Gibson, IBM Corporation.
*
* libfdt is dual licensed: you can use it either under the terms of
* the GPL, or the BSD license, at your option.
*
* a) This library 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 library 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 library; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
* MA 02110-1301 USA
*
* Alternatively,
*
* b) Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "libfdt_env.h"
#include <fdt.h>
#include <libfdt.h>
#include "libfdt_internal.h"
int fdt_check_header(const void *fdt)
{
if (fdt_magic(fdt) == FDT_MAGIC) {
/* Complete tree */
if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
return -FDT_ERR_BADVERSION;
if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)
return -FDT_ERR_BADVERSION;
} else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
/* Unfinished sequential-write blob */
if (fdt_size_dt_struct(fdt) == 0)
return -FDT_ERR_BADSTATE;
} else {
return -FDT_ERR_BADMAGIC;
}
return 0;
}
const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
{
unsigned absoffset = offset + fdt_off_dt_struct(fdt);
if ((absoffset < offset)
|| ((absoffset + len) < absoffset)
|| (absoffset + len) > fdt_totalsize(fdt))
return NULL;
if (fdt_version(fdt) >= 0x11)
if (((offset + len) < offset)
|| ((offset + len) > fdt_size_dt_struct(fdt)))
return NULL;
return _fdt_offset_ptr(fdt, offset);
}
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
{
dtc/libfdt: sparse fixes libfdt/fdt.c:104:28: warning: incorrect type in argument 1 (different base types) libfdt/fdt.c:104:28: expected restricted fdt32_t [usertype] x libfdt/fdt.c:104:28: got unsigned int const [unsigned] [usertype] <noident> libfdt/fdt.c:124:40: warning: incorrect type in argument 1 (different base types) libfdt/fdt.c:124:40: expected restricted fdt32_t [usertype] x libfdt/fdt.c:124:40: got unsigned int const [unsigned] [usertype] <noident> libfdt/fdt_ro.c:337:29: warning: incorrect type in argument 1 (different base types) libfdt/fdt_ro.c:337:29: expected restricted fdt32_t [usertype] x libfdt/fdt_ro.c:337:29: got unsigned int const [unsigned] [usertype] <noident> libfdt/fdt_rw.c:370:17: warning: incorrect type in assignment (different base types) libfdt/fdt_rw.c:370:17: expected unsigned int [unsigned] [usertype] <noident> libfdt/fdt_rw.c:370:17: got restricted fdt32_t libfdt/fdt_sw.c:164:13: warning: incorrect type in assignment (different base types) libfdt/fdt_sw.c:164:13: expected unsigned int [unsigned] [usertype] <noident> libfdt/fdt_sw.c:164:13: got restricted fdt32_t libfdt/fdt_sw.c:227:14: warning: incorrect type in assignment (different base types) libfdt/fdt_sw.c:227:14: expected unsigned int [unsigned] [usertype] <noident> libfdt/fdt_sw.c:227:14: got restricted fdt32_t libfdt/fdt_wip.c:80:20: warning: incorrect type in assignment (different base types) libfdt/fdt_wip.c:80:20: expected unsigned int [unsigned] [usertype] <noident> libfdt/fdt_wip.c:80:20: got restricted fdt32_t libfdt/libfdt.h:1001:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:1001:13: expected unsigned long [unsigned] [usertype] val libfdt/libfdt.h:1001:13: got restricted fdt64_t libfdt/libfdt.h:1157:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:1157:13: expected unsigned int [unsigned] [usertype] val libfdt/libfdt.h:1157:13: got restricted fdt32_t libfdt/libfdt.h:1192:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:1192:13: expected unsigned long [unsigned] [usertype] val libfdt/libfdt.h:1192:13: got restricted fdt64_t libfdt/libfdt.h:1299:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:1299:13: expected unsigned int [unsigned] [usertype] val libfdt/libfdt.h:1299:13: got restricted fdt32_t libfdt/libfdt.h:1334:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:1334:13: expected unsigned long [unsigned] [usertype] val libfdt/libfdt.h:1334:13: got restricted fdt64_t libfdt/libfdt.h:885:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:885:13: expected unsigned int [unsigned] [usertype] val libfdt/libfdt.h:885:13: got restricted fdt32_t libfdt/libfdt.h:920:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:920:13: expected unsigned long [unsigned] [usertype] val libfdt/libfdt.h:920:13: got restricted fdt64_t libfdt/libfdt.h:996:13: warning: incorrect type in assignment (different base types) libfdt/libfdt.h:996:13: expected unsigned int [unsigned] [usertype] val libfdt/libfdt.h:996:13: got restricted fdt32_t Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
12 years ago
const fdt32_t *tagp, *lenp;
uint32_t tag;
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
int offset = startoffset;
const char *p;
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
*nextoffset = -FDT_ERR_TRUNCATED;
tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
if (!tagp)
return FDT_END; /* premature end */
tag = fdt32_to_cpu(*tagp);
offset += FDT_TAGSIZE;
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
*nextoffset = -FDT_ERR_BADSTRUCTURE;
switch (tag) {
case FDT_BEGIN_NODE:
/* skip name */
do {
p = fdt_offset_ptr(fdt, offset++, 1);
} while (p && (*p != '\0'));
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
if (!p)
return FDT_END; /* premature end */
break;
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
case FDT_PROP:
lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
if (!lenp)
return FDT_END; /* premature end */
/* skip-name offset, length and value */
offset += sizeof(struct fdt_property) - FDT_TAGSIZE
+ fdt32_to_cpu(*lenp);
break;
case FDT_END:
case FDT_END_NODE:
case FDT_NOP:
break;
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
default:
return FDT_END;
}
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))
return FDT_END; /* premature end */
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
*nextoffset = FDT_TAGALIGN(offset);
return tag;
}
int _fdt_check_node_offset(const void *fdt, int offset)
{
if ((offset < 0) || (offset % FDT_TAGSIZE)
|| (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))
return -FDT_ERR_BADOFFSET;
return offset;
}
int _fdt_check_prop_offset(const void *fdt, int offset)
{
if ((offset < 0) || (offset % FDT_TAGSIZE)
|| (fdt_next_tag(fdt, offset, &offset) != FDT_PROP))
return -FDT_ERR_BADOFFSET;
return offset;
}
int fdt_next_node(const void *fdt, int offset, int *depth)
{
int nextoffset = 0;
uint32_t tag;
if (offset >= 0)
if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)
return nextoffset;
do {
offset = nextoffset;
tag = fdt_next_tag(fdt, offset, &nextoffset);
switch (tag) {
case FDT_PROP:
case FDT_NOP:
break;
case FDT_BEGIN_NODE:
if (depth)
(*depth)++;
break;
case FDT_END_NODE:
if (depth && ((--(*depth)) < 0))
return nextoffset;
break;
case FDT_END:
libfdt: Rework/cleanup fdt_next_tag() Currently, callers of fdt_next_tag() must usually follow the call with some sort of call to fdt_offset_ptr() to verify that the blob isn't truncated in the middle of the tag data they're going to process. This is a bit silly, since fdt_next_tag() generally has to call fdt_offset_ptr() on at least some of the data following the tag for its own operation. This patch alters fdt_next_tag() to always use fdt_offset_ptr() to verify the data between its starting offset and the offset it returns in nextoffset. This simplifies fdt_get_property() which no longer has to verify itself that the property data is all present. At the same time, I neaten and clarify the error handling for fdt_next_tag(). Previously, fdt_next_tag() could return -1 instead of a tag value in some circumstances - which almost none of the callers checked for. Also, fdt_next_tag() could return FDT_END either because it encountered an FDT_END tag, or because it reached the end of the structure block - no way was provided to tell between these cases. With this patch, fdt_next_tag() always returns FDT_END with a negative value in nextoffset for an error. This means the several places which loop looking for FDT_END will still work correctly - they only need to check for errors at the end. The errors which fdt_next_tag() can report are: - -FDT_ERR_TRUNCATED if it reached the end of the structure block instead of finding a tag. - -FDT_BADSTRUCTURE if a bad tag was encountered, or if the tag data couldn't be verified with fdt_offset_ptr(). This patch also updates the callers of fdt_next_tag(), where appropriate, to make use of the new error reporting. Finally, the prototype for the long gone _fdt_next_tag() is removed from libfdt_internal.h. Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
16 years ago
if ((nextoffset >= 0)
|| ((nextoffset == -FDT_ERR_TRUNCATED) && !depth))
return -FDT_ERR_NOTFOUND;
else
return nextoffset;
}
} while (tag != FDT_BEGIN_NODE);
return offset;
}
int fdt_first_subnode(const void *fdt, int offset)
{
int depth = 0;
offset = fdt_next_node(fdt, offset, &depth);
if (offset < 0 || depth != 1)
return -FDT_ERR_NOTFOUND;
return offset;
}
int fdt_next_subnode(const void *fdt, int offset)
{
int depth = 1;
/*
* With respect to the parent, the depth of the next subnode will be
* the same as the last.
*/
do {
offset = fdt_next_node(fdt, offset, &depth);
if (offset < 0 || depth < 1)
return -FDT_ERR_NOTFOUND;
} while (depth > 1);
return offset;
}
const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)
{
int len = strlen(s) + 1;
const char *last = strtab + tabsize - len;
const char *p;
for (p = strtab; p <= last; p++)
if (memcmp(p, s, len) == 0)
return p;
return NULL;
}
int fdt_move(const void *fdt, void *buf, int bufsize)
{
FDT_CHECK_HEADER(fdt);
if (fdt_totalsize(fdt) > bufsize)
return -FDT_ERR_NOSPACE;
memmove(buf, fdt, fdt_totalsize(fdt));
return 0;
}