1e57a462 |
1 | /*\r |
2 | * libfdt - Flat Device Tree manipulation\r |
3 | * Copyright (C) 2006 David Gibson, IBM Corporation.\r |
4 | *\r |
5 | * libfdt is dual licensed: you can use it either under the terms of\r |
6 | * the GPL, or the BSD license, at your option.\r |
7 | *\r |
8 | * a) This library is free software; you can redistribute it and/or\r |
9 | * modify it under the terms of the GNU General Public License as\r |
10 | * published by the Free Software Foundation; either version 2 of the\r |
11 | * License, or (at your option) any later version.\r |
12 | *\r |
13 | * This library is distributed in the hope that it will be useful,\r |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of\r |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\r |
16 | * GNU General Public License for more details.\r |
17 | *\r |
18 | * You should have received a copy of the GNU General Public\r |
19 | * License along with this library; if not, write to the Free\r |
20 | * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,\r |
21 | * MA 02110-1301 USA\r |
22 | *\r |
23 | * Alternatively,\r |
24 | *\r |
25 | * b) Redistribution and use in source and binary forms, with or\r |
26 | * without modification, are permitted provided that the following\r |
27 | * conditions are met:\r |
28 | *\r |
29 | * 1. Redistributions of source code must retain the above\r |
30 | * copyright notice, this list of conditions and the following\r |
31 | * disclaimer.\r |
32 | * 2. Redistributions in binary form must reproduce the above\r |
33 | * copyright notice, this list of conditions and the following\r |
34 | * disclaimer in the documentation and/or other materials\r |
35 | * provided with the distribution.\r |
36 | *\r |
37 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND\r |
38 | * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,\r |
39 | * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF\r |
40 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE\r |
41 | * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR\r |
42 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\r |
43 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT\r |
44 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;\r |
45 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)\r |
46 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN\r |
47 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR\r |
48 | * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,\r |
49 | * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\r |
50 | */\r |
51 | #include "libfdt_env.h"\r |
52 | \r |
53 | #include <fdt.h>\r |
54 | #include <libfdt.h>\r |
55 | \r |
56 | #include "libfdt_internal.h"\r |
57 | \r |
58 | int fdt_check_header(const void *fdt)\r |
59 | {\r |
60 | if (fdt_magic(fdt) == FDT_MAGIC) {\r |
61 | /* Complete tree */\r |
62 | if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)\r |
63 | return -FDT_ERR_BADVERSION;\r |
64 | if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)\r |
65 | return -FDT_ERR_BADVERSION;\r |
66 | } else if (fdt_magic(fdt) == FDT_SW_MAGIC) {\r |
67 | /* Unfinished sequential-write blob */\r |
68 | if (fdt_size_dt_struct(fdt) == 0)\r |
69 | return -FDT_ERR_BADSTATE;\r |
70 | } else {\r |
71 | return -FDT_ERR_BADMAGIC;\r |
72 | }\r |
73 | \r |
74 | return 0;\r |
75 | }\r |
76 | \r |
77 | const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)\r |
78 | {\r |
79 | const char *p;\r |
80 | \r |
81 | if (fdt_version(fdt) >= 0x11)\r |
82 | if (((offset + len) < offset)\r |
83 | || ((offset + len) > fdt_size_dt_struct(fdt)))\r |
84 | return NULL;\r |
85 | \r |
86 | p = _fdt_offset_ptr(fdt, offset);\r |
87 | \r |
88 | if (p + len < p)\r |
89 | return NULL;\r |
90 | return p;\r |
91 | }\r |
92 | \r |
93 | uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)\r |
94 | {\r |
95 | const uint32_t *tagp, *lenp;\r |
96 | uint32_t tag;\r |
97 | int offset = startoffset;\r |
98 | const char *p;\r |
99 | \r |
100 | *nextoffset = -FDT_ERR_TRUNCATED;\r |
101 | tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);\r |
102 | if (!tagp)\r |
103 | return FDT_END; /* premature end */\r |
104 | tag = fdt32_to_cpu(*tagp);\r |
105 | offset += FDT_TAGSIZE;\r |
106 | \r |
107 | *nextoffset = -FDT_ERR_BADSTRUCTURE;\r |
108 | switch (tag) {\r |
109 | case FDT_BEGIN_NODE:\r |
110 | /* skip name */\r |
111 | do {\r |
112 | p = fdt_offset_ptr(fdt, offset++, 1);\r |
113 | } while (p && (*p != '\0'));\r |
114 | if (!p)\r |
115 | return FDT_END; /* premature end */\r |
116 | break;\r |
117 | \r |
118 | case FDT_PROP:\r |
119 | lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));\r |
120 | if (!lenp)\r |
121 | return FDT_END; /* premature end */\r |
122 | /* skip-name offset, length and value */\r |
123 | offset += sizeof(struct fdt_property) - FDT_TAGSIZE\r |
124 | + fdt32_to_cpu(*lenp);\r |
125 | break;\r |
126 | \r |
127 | case FDT_END:\r |
128 | case FDT_END_NODE:\r |
129 | case FDT_NOP:\r |
130 | break;\r |
131 | \r |
132 | default:\r |
133 | return FDT_END;\r |
134 | }\r |
135 | \r |
136 | if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))\r |
137 | return FDT_END; /* premature end */\r |
138 | \r |
139 | *nextoffset = FDT_TAGALIGN(offset);\r |
140 | return tag;\r |
141 | }\r |
142 | \r |
143 | int _fdt_check_node_offset(const void *fdt, int offset)\r |
144 | {\r |
145 | if ((offset < 0) || (offset % FDT_TAGSIZE)\r |
146 | || (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))\r |
147 | return -FDT_ERR_BADOFFSET;\r |
148 | \r |
149 | return offset;\r |
150 | }\r |
151 | \r |
152 | int _fdt_check_prop_offset(const void *fdt, int offset)\r |
153 | {\r |
154 | if ((offset < 0) || (offset % FDT_TAGSIZE)\r |
155 | || (fdt_next_tag(fdt, offset, &offset) != FDT_PROP))\r |
156 | return -FDT_ERR_BADOFFSET;\r |
157 | \r |
158 | return offset;\r |
159 | }\r |
160 | \r |
161 | int fdt_next_node(const void *fdt, int offset, int *depth)\r |
162 | {\r |
163 | int nextoffset = 0;\r |
164 | uint32_t tag;\r |
165 | \r |
166 | if (offset >= 0)\r |
167 | if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)\r |
168 | return nextoffset;\r |
169 | \r |
170 | do {\r |
171 | offset = nextoffset;\r |
172 | tag = fdt_next_tag(fdt, offset, &nextoffset);\r |
173 | \r |
174 | switch (tag) {\r |
175 | case FDT_PROP:\r |
176 | case FDT_NOP:\r |
177 | break;\r |
178 | \r |
179 | case FDT_BEGIN_NODE:\r |
180 | if (depth)\r |
181 | (*depth)++;\r |
182 | break;\r |
183 | \r |
184 | case FDT_END_NODE:\r |
185 | if (depth && ((--(*depth)) < 0))\r |
186 | return nextoffset;\r |
187 | break;\r |
188 | \r |
189 | case FDT_END:\r |
190 | if ((nextoffset >= 0)\r |
191 | || ((nextoffset == -FDT_ERR_TRUNCATED) && !depth))\r |
192 | return -FDT_ERR_NOTFOUND;\r |
193 | else\r |
194 | return nextoffset;\r |
195 | }\r |
196 | } while (tag != FDT_BEGIN_NODE);\r |
197 | \r |
198 | return offset;\r |
199 | }\r |
200 | \r |
201 | const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)\r |
202 | {\r |
203 | int len = strlen(s) + 1;\r |
204 | const char *last = strtab + tabsize - len;\r |
205 | const char *p;\r |
206 | \r |
207 | for (p = strtab; p <= last; p++)\r |
208 | if (memcmp(p, s, len) == 0)\r |
209 | return p;\r |
210 | return NULL;\r |
211 | }\r |
212 | \r |
213 | int fdt_move(const void *fdt, void *buf, int bufsize)\r |
214 | {\r |
215 | FDT_CHECK_HEADER(fdt);\r |
216 | \r |
217 | if (fdt_totalsize(fdt) > bufsize)\r |
218 | return -FDT_ERR_NOSPACE;\r |
219 | \r |
220 | memmove(buf, fdt, fdt_totalsize(fdt));\r |
221 | return 0;\r |
222 | }\r |