u-boot/lib/libfdt/fdt_sw.c

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/*
* libfdt - Flat Device Tree manipulation
* Copyright (C) 2006 David Gibson, IBM Corporation.
* SPDX-License-Identifier: GPL-2.0+ BSD-2-Clause
*/
#include "libfdt_env.h"
#include <fdt.h>
#include <libfdt.h>
#include "libfdt_internal.h"
static int _fdt_sw_check_header(void *fdt)
{
if (fdt_magic(fdt) != FDT_SW_MAGIC)
return -FDT_ERR_BADMAGIC;
/* FIXME: should check more details about the header state */
return 0;
}
#define FDT_SW_CHECK_HEADER(fdt) \
{ \
int err; \
if ((err = _fdt_sw_check_header(fdt)) != 0) \
return err; \
}
static void *_fdt_grab_space(void *fdt, size_t len)
{
int offset = fdt_size_dt_struct(fdt);
int spaceleft;
spaceleft = fdt_totalsize(fdt) - fdt_off_dt_struct(fdt)
- fdt_size_dt_strings(fdt);
if ((offset + len < offset) || (offset + len > spaceleft))
return NULL;
fdt_set_size_dt_struct(fdt, offset + len);
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>
2009-02-06 03:03:24 +00:00
return _fdt_offset_ptr_w(fdt, offset);
}
int fdt_create(void *buf, int bufsize)
{
void *fdt = buf;
if (bufsize < sizeof(struct fdt_header))
return -FDT_ERR_NOSPACE;
memset(buf, 0, bufsize);
fdt_set_magic(fdt, FDT_SW_MAGIC);
fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
fdt_set_totalsize(fdt, bufsize);
fdt_set_off_mem_rsvmap(fdt, FDT_ALIGN(sizeof(struct fdt_header),
sizeof(struct fdt_reserve_entry)));
fdt_set_off_dt_struct(fdt, fdt_off_mem_rsvmap(fdt));
fdt_set_off_dt_strings(fdt, bufsize);
return 0;
}
int fdt_resize(void *fdt, void *buf, int bufsize)
{
size_t headsize, tailsize;
char *oldtail, *newtail;
FDT_SW_CHECK_HEADER(fdt);
headsize = fdt_off_dt_struct(fdt);
tailsize = fdt_size_dt_strings(fdt);
if ((headsize + tailsize) > bufsize)
return -FDT_ERR_NOSPACE;
oldtail = (char *)fdt + fdt_totalsize(fdt) - tailsize;
newtail = (char *)buf + bufsize - tailsize;
/* Two cases to avoid clobbering data if the old and new
* buffers partially overlap */
if (buf <= fdt) {
memmove(buf, fdt, headsize);
memmove(newtail, oldtail, tailsize);
} else {
memmove(newtail, oldtail, tailsize);
memmove(buf, fdt, headsize);
}
fdt_set_off_dt_strings(buf, bufsize);
fdt_set_totalsize(buf, bufsize);
return 0;
}
int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size)
{
struct fdt_reserve_entry *re;
int offset;
FDT_SW_CHECK_HEADER(fdt);
if (fdt_size_dt_struct(fdt))
return -FDT_ERR_BADSTATE;
offset = fdt_off_dt_struct(fdt);
if ((offset + sizeof(*re)) > fdt_totalsize(fdt))
return -FDT_ERR_NOSPACE;
re = (struct fdt_reserve_entry *)((char *)fdt + offset);
re->address = cpu_to_fdt64(addr);
re->size = cpu_to_fdt64(size);
fdt_set_off_dt_struct(fdt, offset + sizeof(*re));
return 0;
}
int fdt_finish_reservemap(void *fdt)
{
return fdt_add_reservemap_entry(fdt, 0, 0);
}
int fdt_begin_node(void *fdt, const char *name)
{
struct fdt_node_header *nh;
int namelen = strlen(name) + 1;
FDT_SW_CHECK_HEADER(fdt);
nh = _fdt_grab_space(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen));
if (! nh)
return -FDT_ERR_NOSPACE;
nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
memcpy(nh->name, name, namelen);
return 0;
}
int fdt_end_node(void *fdt)
{
fdt32_t *en;
FDT_SW_CHECK_HEADER(fdt);
en = _fdt_grab_space(fdt, FDT_TAGSIZE);
if (! en)
return -FDT_ERR_NOSPACE;
*en = cpu_to_fdt32(FDT_END_NODE);
return 0;
}
static int _fdt_find_add_string(void *fdt, const char *s)
{
char *strtab = (char *)fdt + fdt_totalsize(fdt);
const char *p;
int strtabsize = fdt_size_dt_strings(fdt);
int len = strlen(s) + 1;
int struct_top, offset;
p = _fdt_find_string(strtab - strtabsize, strtabsize, s);
if (p)
return p - strtab;
/* Add it */
offset = -strtabsize - len;
struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
if (fdt_totalsize(fdt) + offset < struct_top)
return 0; /* no more room :( */
memcpy(strtab + offset, s, len);
fdt_set_size_dt_strings(fdt, strtabsize + len);
return offset;
}
int fdt_property(void *fdt, const char *name, const void *val, int len)
{
struct fdt_property *prop;
int nameoff;
FDT_SW_CHECK_HEADER(fdt);
nameoff = _fdt_find_add_string(fdt, name);
if (nameoff == 0)
return -FDT_ERR_NOSPACE;
prop = _fdt_grab_space(fdt, sizeof(*prop) + FDT_TAGALIGN(len));
if (! prop)
return -FDT_ERR_NOSPACE;
prop->tag = cpu_to_fdt32(FDT_PROP);
prop->nameoff = cpu_to_fdt32(nameoff);
prop->len = cpu_to_fdt32(len);
memcpy(prop->data, val, len);
return 0;
}
int fdt_finish(void *fdt)
{
char *p = (char *)fdt;
fdt32_t *end;
int oldstroffset, newstroffset;
uint32_t tag;
int offset, nextoffset;
FDT_SW_CHECK_HEADER(fdt);
/* Add terminator */
end = _fdt_grab_space(fdt, sizeof(*end));
if (! end)
return -FDT_ERR_NOSPACE;
*end = cpu_to_fdt32(FDT_END);
/* Relocate the string table */
oldstroffset = fdt_totalsize(fdt) - fdt_size_dt_strings(fdt);
newstroffset = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
memmove(p + newstroffset, p + oldstroffset, fdt_size_dt_strings(fdt));
fdt_set_off_dt_strings(fdt, newstroffset);
/* Walk the structure, correcting string offsets */
offset = 0;
while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) {
if (tag == FDT_PROP) {
struct fdt_property *prop =
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>
2009-02-06 03:03:24 +00:00
_fdt_offset_ptr_w(fdt, offset);
int nameoff;
nameoff = fdt32_to_cpu(prop->nameoff);
nameoff += fdt_size_dt_strings(fdt);
prop->nameoff = cpu_to_fdt32(nameoff);
}
offset = nextoffset;
}
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>
2009-02-06 03:03:24 +00:00
if (nextoffset < 0)
return nextoffset;
/* Finally, adjust the header */
fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt));
fdt_set_magic(fdt, FDT_MAGIC);
return 0;
}