Edit File: fdt.c
/* * 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) { const char *p; if (fdt_version(fdt) >= 0x11) if (((offset + len) < offset) || ((offset + len) > fdt_size_dt_struct(fdt))) return NULL; p = _fdt_offset_ptr(fdt, offset); if (p + len < p) return NULL; return p; } uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset) { const uint32_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 (!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 (!p) return FDT_END; /* premature end */ break; case FDT_PROP: lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp)); 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; 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 ((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: if ((nextoffset >= 0) || ((nextoffset == -FDT_ERR_TRUNCATED) && !depth)) return -FDT_ERR_NOTFOUND; else return nextoffset; } } while (tag != FDT_BEGIN_NODE); 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; }