1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22#include "udfdecl.h"
23
24#include <linux/fs.h>
25#include <linux/string.h>
26#include <linux/crc-itu-t.h>
27
28#include "udf_i.h"
29#include "udf_sb.h"
30
31struct buffer_head *udf_tgetblk(struct super_block *sb, udf_pblk_t block)
32{
33 if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
34 return sb_getblk(sb, udf_fixed_to_variable(block));
35 else
36 return sb_getblk(sb, block);
37}
38
39struct buffer_head *udf_tread(struct super_block *sb, udf_pblk_t block)
40{
41 if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
42 return sb_bread(sb, udf_fixed_to_variable(block));
43 else
44 return sb_bread(sb, block);
45}
46
47struct genericFormat *udf_add_extendedattr(struct inode *inode, uint32_t size,
48 uint32_t type, uint8_t loc)
49{
50 uint8_t *ea = NULL, *ad = NULL;
51 int offset;
52 uint16_t crclen;
53 struct udf_inode_info *iinfo = UDF_I(inode);
54
55 ea = iinfo->i_ext.i_data;
56 if (iinfo->i_lenEAttr) {
57 ad = iinfo->i_ext.i_data + iinfo->i_lenEAttr;
58 } else {
59 ad = ea;
60 size += sizeof(struct extendedAttrHeaderDesc);
61 }
62
63 offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
64 iinfo->i_lenAlloc;
65
66
67
68 if (loc & 0x01 && offset >= size) {
69 struct extendedAttrHeaderDesc *eahd;
70 eahd = (struct extendedAttrHeaderDesc *)ea;
71
72 if (iinfo->i_lenAlloc)
73 memmove(&ad[size], ad, iinfo->i_lenAlloc);
74
75 if (iinfo->i_lenEAttr) {
76
77 if (eahd->descTag.tagIdent !=
78 cpu_to_le16(TAG_IDENT_EAHD) ||
79 le32_to_cpu(eahd->descTag.tagLocation) !=
80 iinfo->i_location.logicalBlockNum)
81 return NULL;
82 } else {
83 struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
84
85 size -= sizeof(struct extendedAttrHeaderDesc);
86 iinfo->i_lenEAttr +=
87 sizeof(struct extendedAttrHeaderDesc);
88 eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
89 if (sbi->s_udfrev >= 0x0200)
90 eahd->descTag.descVersion = cpu_to_le16(3);
91 else
92 eahd->descTag.descVersion = cpu_to_le16(2);
93 eahd->descTag.tagSerialNum =
94 cpu_to_le16(sbi->s_serial_number);
95 eahd->descTag.tagLocation = cpu_to_le32(
96 iinfo->i_location.logicalBlockNum);
97 eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
98 eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
99 }
100
101 offset = iinfo->i_lenEAttr;
102 if (type < 2048) {
103 if (le32_to_cpu(eahd->appAttrLocation) <
104 iinfo->i_lenEAttr) {
105 uint32_t aal =
106 le32_to_cpu(eahd->appAttrLocation);
107 memmove(&ea[offset - aal + size],
108 &ea[aal], offset - aal);
109 offset -= aal;
110 eahd->appAttrLocation =
111 cpu_to_le32(aal + size);
112 }
113 if (le32_to_cpu(eahd->impAttrLocation) <
114 iinfo->i_lenEAttr) {
115 uint32_t ial =
116 le32_to_cpu(eahd->impAttrLocation);
117 memmove(&ea[offset - ial + size],
118 &ea[ial], offset - ial);
119 offset -= ial;
120 eahd->impAttrLocation =
121 cpu_to_le32(ial + size);
122 }
123 } else if (type < 65536) {
124 if (le32_to_cpu(eahd->appAttrLocation) <
125 iinfo->i_lenEAttr) {
126 uint32_t aal =
127 le32_to_cpu(eahd->appAttrLocation);
128 memmove(&ea[offset - aal + size],
129 &ea[aal], offset - aal);
130 offset -= aal;
131 eahd->appAttrLocation =
132 cpu_to_le32(aal + size);
133 }
134 }
135
136 crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(struct tag);
137 eahd->descTag.descCRCLength = cpu_to_le16(crclen);
138 eahd->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)eahd +
139 sizeof(struct tag), crclen));
140 eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag);
141 iinfo->i_lenEAttr += size;
142 return (struct genericFormat *)&ea[offset];
143 }
144
145 return NULL;
146}
147
148struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type,
149 uint8_t subtype)
150{
151 struct genericFormat *gaf;
152 uint8_t *ea = NULL;
153 uint32_t offset;
154 struct udf_inode_info *iinfo = UDF_I(inode);
155
156 ea = iinfo->i_ext.i_data;
157
158 if (iinfo->i_lenEAttr) {
159 struct extendedAttrHeaderDesc *eahd;
160 eahd = (struct extendedAttrHeaderDesc *)ea;
161
162
163 if (eahd->descTag.tagIdent !=
164 cpu_to_le16(TAG_IDENT_EAHD) ||
165 le32_to_cpu(eahd->descTag.tagLocation) !=
166 iinfo->i_location.logicalBlockNum)
167 return NULL;
168
169 if (type < 2048)
170 offset = sizeof(struct extendedAttrHeaderDesc);
171 else if (type < 65536)
172 offset = le32_to_cpu(eahd->impAttrLocation);
173 else
174 offset = le32_to_cpu(eahd->appAttrLocation);
175
176 while (offset < iinfo->i_lenEAttr) {
177 gaf = (struct genericFormat *)&ea[offset];
178 if (le32_to_cpu(gaf->attrType) == type &&
179 gaf->attrSubtype == subtype)
180 return gaf;
181 else
182 offset += le32_to_cpu(gaf->attrLength);
183 }
184 }
185
186 return NULL;
187}
188
189
190
191
192
193
194
195
196
197
198
199struct buffer_head *udf_read_tagged(struct super_block *sb, uint32_t block,
200 uint32_t location, uint16_t *ident)
201{
202 struct tag *tag_p;
203 struct buffer_head *bh = NULL;
204 u8 checksum;
205
206
207 if (block == 0xFFFFFFFF)
208 return NULL;
209
210 bh = udf_tread(sb, block);
211 if (!bh) {
212 udf_err(sb, "read failed, block=%u, location=%u\n",
213 block, location);
214 return NULL;
215 }
216
217 tag_p = (struct tag *)(bh->b_data);
218
219 *ident = le16_to_cpu(tag_p->tagIdent);
220
221 if (location != le32_to_cpu(tag_p->tagLocation)) {
222 udf_debug("location mismatch block %u, tag %u != %u\n",
223 block, le32_to_cpu(tag_p->tagLocation), location);
224 goto error_out;
225 }
226
227
228 checksum = udf_tag_checksum(tag_p);
229 if (checksum != tag_p->tagChecksum) {
230 udf_err(sb, "tag checksum failed, block %u: 0x%02x != 0x%02x\n",
231 block, checksum, tag_p->tagChecksum);
232 goto error_out;
233 }
234
235
236 if (tag_p->descVersion != cpu_to_le16(0x0002U) &&
237 tag_p->descVersion != cpu_to_le16(0x0003U)) {
238 udf_err(sb, "tag version 0x%04x != 0x0002 || 0x0003, block %u\n",
239 le16_to_cpu(tag_p->descVersion), block);
240 goto error_out;
241 }
242
243
244 if (le16_to_cpu(tag_p->descCRCLength) + sizeof(struct tag) > sb->s_blocksize ||
245 le16_to_cpu(tag_p->descCRC) == crc_itu_t(0,
246 bh->b_data + sizeof(struct tag),
247 le16_to_cpu(tag_p->descCRCLength)))
248 return bh;
249
250 udf_debug("Crc failure block %u: crc = %u, crclen = %u\n", block,
251 le16_to_cpu(tag_p->descCRC),
252 le16_to_cpu(tag_p->descCRCLength));
253error_out:
254 brelse(bh);
255 return NULL;
256}
257
258struct buffer_head *udf_read_ptagged(struct super_block *sb,
259 struct kernel_lb_addr *loc,
260 uint32_t offset, uint16_t *ident)
261{
262 return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
263 loc->logicalBlockNum + offset, ident);
264}
265
266void udf_update_tag(char *data, int length)
267{
268 struct tag *tptr = (struct tag *)data;
269 length -= sizeof(struct tag);
270
271 tptr->descCRCLength = cpu_to_le16(length);
272 tptr->descCRC = cpu_to_le16(crc_itu_t(0, data + sizeof(struct tag), length));
273 tptr->tagChecksum = udf_tag_checksum(tptr);
274}
275
276void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
277 uint32_t loc, int length)
278{
279 struct tag *tptr = (struct tag *)data;
280 tptr->tagIdent = cpu_to_le16(ident);
281 tptr->descVersion = cpu_to_le16(version);
282 tptr->tagSerialNum = cpu_to_le16(snum);
283 tptr->tagLocation = cpu_to_le32(loc);
284 udf_update_tag(data, length);
285}
286
287u8 udf_tag_checksum(const struct tag *t)
288{
289 u8 *data = (u8 *)t;
290 u8 checksum = 0;
291 int i;
292 for (i = 0; i < sizeof(struct tag); ++i)
293 if (i != 4)
294 checksum += data[i];
295 return checksum;
296}
297
