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-rw-r--r--scripts/dtc/libfdt/fdt.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/scripts/dtc/libfdt/fdt.c b/scripts/dtc/libfdt/fdt.c
new file mode 100644
index 000000000..6cf2fa03b
--- /dev/null
+++ b/scripts/dtc/libfdt/fdt.c
@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
+/*
+ * libfdt - Flat Device Tree manipulation
+ * Copyright (C) 2006 David Gibson, IBM Corporation.
+ */
+#include "libfdt_env.h"
+
+#include <fdt.h>
+#include <libfdt.h>
+
+#include "libfdt_internal.h"
+
+/*
+ * Minimal sanity check for a read-only tree. fdt_ro_probe_() checks
+ * that the given buffer contains what appears to be a flattened
+ * device tree with sane information in its header.
+ */
+int32_t fdt_ro_probe_(const void *fdt)
+{
+ uint32_t totalsize = fdt_totalsize(fdt);
+
+ if (can_assume(VALID_DTB))
+ return totalsize;
+
+ if (fdt_magic(fdt) == FDT_MAGIC) {
+ /* Complete tree */
+ if (!can_assume(LATEST)) {
+ 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 (!can_assume(VALID_INPUT) && fdt_size_dt_struct(fdt) == 0)
+ return -FDT_ERR_BADSTATE;
+ } else {
+ return -FDT_ERR_BADMAGIC;
+ }
+
+ if (totalsize < INT32_MAX)
+ return totalsize;
+ else
+ return -FDT_ERR_TRUNCATED;
+}
+
+static int check_off_(uint32_t hdrsize, uint32_t totalsize, uint32_t off)
+{
+ return (off >= hdrsize) && (off <= totalsize);
+}
+
+static int check_block_(uint32_t hdrsize, uint32_t totalsize,
+ uint32_t base, uint32_t size)
+{
+ if (!check_off_(hdrsize, totalsize, base))
+ return 0; /* block start out of bounds */
+ if ((base + size) < base)
+ return 0; /* overflow */
+ if (!check_off_(hdrsize, totalsize, base + size))
+ return 0; /* block end out of bounds */
+ return 1;
+}
+
+size_t fdt_header_size_(uint32_t version)
+{
+ if (version <= 1)
+ return FDT_V1_SIZE;
+ else if (version <= 2)
+ return FDT_V2_SIZE;
+ else if (version <= 3)
+ return FDT_V3_SIZE;
+ else if (version <= 16)
+ return FDT_V16_SIZE;
+ else
+ return FDT_V17_SIZE;
+}
+
+size_t fdt_header_size(const void *fdt)
+{
+ return can_assume(LATEST) ? FDT_V17_SIZE :
+ fdt_header_size_(fdt_version(fdt));
+}
+
+int fdt_check_header(const void *fdt)
+{
+ size_t hdrsize;
+
+ if (fdt_magic(fdt) != FDT_MAGIC)
+ return -FDT_ERR_BADMAGIC;
+ if (!can_assume(LATEST)) {
+ if ((fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
+ || (fdt_last_comp_version(fdt) >
+ FDT_LAST_SUPPORTED_VERSION))
+ return -FDT_ERR_BADVERSION;
+ if (fdt_version(fdt) < fdt_last_comp_version(fdt))
+ return -FDT_ERR_BADVERSION;
+ }
+ hdrsize = fdt_header_size(fdt);
+ if (!can_assume(VALID_DTB)) {
+
+ if ((fdt_totalsize(fdt) < hdrsize)
+ || (fdt_totalsize(fdt) > INT_MAX))
+ return -FDT_ERR_TRUNCATED;
+
+ /* Bounds check memrsv block */
+ if (!check_off_(hdrsize, fdt_totalsize(fdt),
+ fdt_off_mem_rsvmap(fdt)))
+ return -FDT_ERR_TRUNCATED;
+ }
+
+ if (!can_assume(VALID_DTB)) {
+ /* Bounds check structure block */
+ if (!can_assume(LATEST) && fdt_version(fdt) < 17) {
+ if (!check_off_(hdrsize, fdt_totalsize(fdt),
+ fdt_off_dt_struct(fdt)))
+ return -FDT_ERR_TRUNCATED;
+ } else {
+ if (!check_block_(hdrsize, fdt_totalsize(fdt),
+ fdt_off_dt_struct(fdt),
+ fdt_size_dt_struct(fdt)))
+ return -FDT_ERR_TRUNCATED;
+ }
+
+ /* Bounds check strings block */
+ if (!check_block_(hdrsize, fdt_totalsize(fdt),
+ fdt_off_dt_strings(fdt),
+ fdt_size_dt_strings(fdt)))
+ return -FDT_ERR_TRUNCATED;
+ }
+
+ return 0;
+}
+
+const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
+{
+ unsigned int uoffset = offset;
+ unsigned int absoffset = offset + fdt_off_dt_struct(fdt);
+
+ if (offset < 0)
+ return NULL;
+
+ if (!can_assume(VALID_INPUT))
+ if ((absoffset < uoffset)
+ || ((absoffset + len) < absoffset)
+ || (absoffset + len) > fdt_totalsize(fdt))
+ return NULL;
+
+ if (can_assume(LATEST) || fdt_version(fdt) >= 0x11)
+ if (((uoffset + len) < uoffset)
+ || ((offset + len) > fdt_size_dt_struct(fdt)))
+ return NULL;
+
+ return fdt_offset_ptr_(fdt, offset);
+}
+
+uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
+{
+ const fdt32_t *tagp, *lenp;
+ uint32_t tag;
+ int offset = startoffset;
+ const char *p;
+
+ *nextoffset = -FDT_ERR_TRUNCATED;
+ tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
+ if (!can_assume(VALID_DTB) && !tagp)
+ return FDT_END; /* premature end */
+ tag = fdt32_to_cpu(*tagp);
+ offset += FDT_TAGSIZE;
+
+ *nextoffset = -FDT_ERR_BADSTRUCTURE;
+ switch (tag) {
+ case FDT_BEGIN_NODE:
+ /* skip name */
+ do {
+ p = fdt_offset_ptr(fdt, offset++, 1);
+ } while (p && (*p != '\0'));
+ if (!can_assume(VALID_DTB) && !p)
+ return FDT_END; /* premature end */
+ break;
+
+ case FDT_PROP:
+ lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
+ if (!can_assume(VALID_DTB) && !lenp)
+ return FDT_END; /* premature end */
+ /* skip-name offset, length and value */
+ offset += sizeof(struct fdt_property) - FDT_TAGSIZE
+ + fdt32_to_cpu(*lenp);
+ if (!can_assume(LATEST) &&
+ fdt_version(fdt) < 0x10 && fdt32_to_cpu(*lenp) >= 8 &&
+ ((offset - fdt32_to_cpu(*lenp)) % 8) != 0)
+ offset += 4;
+ break;
+
+ case FDT_END:
+ case FDT_END_NODE:
+ case FDT_NOP:
+ break;
+
+ default:
+ return FDT_END;
+ }
+
+ if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))
+ return FDT_END; /* premature end */
+
+ *nextoffset = FDT_TAGALIGN(offset);
+ return tag;
+}
+
+int fdt_check_node_offset_(const void *fdt, int offset)
+{
+ if (!can_assume(VALID_INPUT)
+ && ((offset < 0) || (offset % FDT_TAGSIZE)))
+ return -FDT_ERR_BADOFFSET;
+
+ if (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 (!can_assume(VALID_INPUT)
+ && ((offset < 0) || (offset % FDT_TAGSIZE)))
+ return -FDT_ERR_BADOFFSET;
+
+ if (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:
+ 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)
+{
+ if (!can_assume(VALID_INPUT) && bufsize < 0)
+ return -FDT_ERR_NOSPACE;
+
+ FDT_RO_PROBE(fdt);
+
+ if (fdt_totalsize(fdt) > (unsigned int)bufsize)
+ return -FDT_ERR_NOSPACE;
+
+ memmove(buf, fdt, fdt_totalsize(fdt));
+ return 0;
+}