fs/hpfs/ea.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/hpfs/ea.c
   4  *
   5  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   6  *
   7  *  handling extended attributes
   8  */
   9
  10 #include "hpfs_fn.h"
  11
  12 /* Remove external extended attributes. ano specifies whether a is a
  13    direct sector where eas starts or an anode */
  14
  15 void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
  16 {
  17         unsigned pos = 0;
  18         while (pos < len) {
  19                 char ex[4 + 255 + 1 + 8];
  20                 struct extended_attribute *ea = (struct extended_attribute *)ex;
  21                 if (pos + 4 > len) {
  22                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
  23                                 ano ? "anode" : "sectors", a, len);
  24                         return;
  25                 }
  26                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
  27                 if (ea_indirect(ea)) {
  28                         if (ea_valuelen(ea) != 8) {
  29                                 hpfs_error(s, "ea_indirect(ea) set while ea->valuelen!=8, %s %08x, pos %08x",
  30                                         ano ? "anode" : "sectors", a, pos);
  31                                 return;
  32                         }
  33                         if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
  34                                 return;
  35                         hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
  36                 }
  37                 pos += ea->namelen + ea_valuelen(ea) + 5;
  38         }
  39         if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
  40         else {
  41                 struct buffer_head *bh;
  42                 struct anode *anode;
  43                 if ((anode = hpfs_map_anode(s, a, &bh))) {
  44                         hpfs_remove_btree(s, &anode->btree);
  45                         brelse(bh);
  46                         hpfs_free_sectors(s, a, 1);
  47                 }
  48         }
  49 }
  50
  51 static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
  52 {
  53         char *ret;
  54         if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
  55                 pr_err("out of memory for EA\n");
  56                 return NULL;
  57         }
  58         if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
  59                 kfree(ret);
  60                 return NULL;
  61         }
  62         ret[size] = 0;
  63         return ret;
  64 }
  65
  66 static void set_indirect_ea(struct super_block *s, int ano, secno a,
  67                             const char *data, int size)
  68 {
  69         hpfs_ea_write(s, a, ano, 0, size, data);
  70 }
  71
  72 /* Read an extended attribute named 'key' into the provided buffer */
  73
  74 int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
  75                 char *buf, int size)
  76 {
  77         unsigned pos;
  78         int ano, len;
  79         secno a;
  80         char ex[4 + 255 + 1 + 8];
  81         struct extended_attribute *ea;
  82         struct extended_attribute *ea_end = fnode_end_ea(fnode);
  83         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
  84                 if (!strcmp(ea->name, key)) {
  85                         if (ea_indirect(ea))
  86                                 goto indirect;
  87                         if (ea_valuelen(ea) >= size)
  88                                 return -EINVAL;
  89                         memcpy(buf, ea_data(ea), ea_valuelen(ea));
  90                         buf[ea_valuelen(ea)] = 0;
  91                         return 0;
  92                 }
  93         a = le32_to_cpu(fnode->ea_secno);
  94         len = le32_to_cpu(fnode->ea_size_l);
  95         ano = fnode_in_anode(fnode);
  96         pos = 0;
  97         while (pos < len) {
  98                 ea = (struct extended_attribute *)ex;
  99                 if (pos + 4 > len) {
 100                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 101                                 ano ? "anode" : "sectors", a, len);
 102                         return -EIO;
 103                 }
 104                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
 105                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
 106                         return -EIO;
 107                 if (!strcmp(ea->name, key)) {
 108                         if (ea_indirect(ea))
 109                                 goto indirect;
 110                         if (ea_valuelen(ea) >= size)
 111                                 return -EINVAL;
 112                         if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), buf))
 113                                 return -EIO;
 114                         buf[ea_valuelen(ea)] = 0;
 115                         return 0;
 116                 }
 117                 pos += ea->namelen + ea_valuelen(ea) + 5;
 118         }
 119         return -ENOENT;
 120 indirect:
 121         if (ea_len(ea) >= size)
 122                 return -EINVAL;
 123         if (hpfs_ea_read(s, ea_sec(ea), ea_in_anode(ea), 0, ea_len(ea), buf))
 124                 return -EIO;
 125         buf[ea_len(ea)] = 0;
 126         return 0;
 127 }
 128
 129 /* Read an extended attribute named 'key' */
 130 char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
 131 {
 132         char *ret;
 133         unsigned pos;
 134         int ano, len;
 135         secno a;
 136         struct extended_attribute *ea;
 137         struct extended_attribute *ea_end = fnode_end_ea(fnode);
 138         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 139                 if (!strcmp(ea->name, key)) {
 140                         if (ea_indirect(ea))
 141                                 return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
 142                         if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
 143                                 pr_err("out of memory for EA\n");
 144                                 return NULL;
 145                         }
 146                         memcpy(ret, ea_data(ea), ea_valuelen(ea));
 147                         ret[ea_valuelen(ea)] = 0;
 148                         return ret;
 149                 }
 150         a = le32_to_cpu(fnode->ea_secno);
 151         len = le32_to_cpu(fnode->ea_size_l);
 152         ano = fnode_in_anode(fnode);
 153         pos = 0;
 154         while (pos < len) {
 155                 char ex[4 + 255 + 1 + 8];
 156                 ea = (struct extended_attribute *)ex;
 157                 if (pos + 4 > len) {
 158                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 159                                 ano ? "anode" : "sectors", a, len);
 160                         return NULL;
 161                 }
 162                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
 163                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
 164                         return NULL;
 165                 if (!strcmp(ea->name, key)) {
 166                         if (ea_indirect(ea))
 167                                 return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
 168                         if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
 169                                 pr_err("out of memory for EA\n");
 170                                 return NULL;
 171                         }
 172                         if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), ret)) {
 173                                 kfree(ret);
 174                                 return NULL;
 175                         }
 176                         ret[ea_valuelen(ea)] = 0;
 177                         return ret;
 178                 }
 179                 pos += ea->namelen + ea_valuelen(ea) + 5;
 180         }
 181         return NULL;
 182 }
 183
 184 /*
 185  * Update or create extended attribute 'key' with value 'data'. Note that
 186  * when this ea exists, it MUST have the same size as size of data.
 187  * This driver can't change sizes of eas ('cause I just don't need it).
 188  */
 189
 190 void hpfs_set_ea(struct inode *inode, struct fnode *fnode, const char *key,
 191                  const char *data, int size)
 192 {
 193         fnode_secno fno = inode->i_ino;
 194         struct super_block *s = inode->i_sb;
 195         unsigned pos;
 196         int ano, len;
 197         secno a;
 198         unsigned char h[4];
 199         struct extended_attribute *ea;
 200         struct extended_attribute *ea_end = fnode_end_ea(fnode);
 201         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 202                 if (!strcmp(ea->name, key)) {
 203                         if (ea_indirect(ea)) {
 204                                 if (ea_len(ea) == size)
 205                                         set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
 206                         } else if (ea_valuelen(ea) == size) {
 207                                 memcpy(ea_data(ea), data, size);
 208                         }
 209                         return;
 210                 }
 211         a = le32_to_cpu(fnode->ea_secno);
 212         len = le32_to_cpu(fnode->ea_size_l);
 213         ano = fnode_in_anode(fnode);
 214         pos = 0;
 215         while (pos < len) {
 216                 char ex[4 + 255 + 1 + 8];
 217                 ea = (struct extended_attribute *)ex;
 218                 if (pos + 4 > len) {
 219                         hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
 220                                 ano ? "anode" : "sectors", a, len);
 221                         return;
 222                 }
 223                 if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
 224                 if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
 225                         return;
 226                 if (!strcmp(ea->name, key)) {
 227                         if (ea_indirect(ea)) {
 228                                 if (ea_len(ea) == size)
 229                                         set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
 230                         }
 231                         else {
 232                                 if (ea_valuelen(ea) == size)
 233                                         hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
 234                         }
 235                         return;
 236                 }
 237                 pos += ea->namelen + ea_valuelen(ea) + 5;
 238         }
 239         if (!le16_to_cpu(fnode->ea_offs)) {
 240                 /*if (le16_to_cpu(fnode->ea_size_s)) {
 241                         hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
 242                                 inode->i_ino, le16_to_cpu(fnode->ea_size_s));
 243                         return;
 244                 }*/
 245                 fnode->ea_offs = cpu_to_le16(0xc4);
 246         }
 247         if (le16_to_cpu(fnode->ea_offs) < 0xc4 || le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200) {
 248                 hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
 249                         (unsigned long)inode->i_ino,
 250                         le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
 251                 return;
 252         }
 253         if ((le16_to_cpu(fnode->ea_size_s) || !le32_to_cpu(fnode->ea_size_l)) &&
 254              le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5 <= 0x200) {
 255                 ea = fnode_end_ea(fnode);
 256                 *(char *)ea = 0;
 257                 ea->namelen = strlen(key);
 258                 ea->valuelen_lo = size;
 259                 ea->valuelen_hi = size >> 8;
 260                 strcpy(ea->name, key);
 261                 memcpy(ea_data(ea), data, size);
 262                 fnode->ea_size_s = cpu_to_le16(le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5);
 263                 goto ret;
 264         }
 265         /* Most the code here is 99.9993422% unused. I hope there are no bugs.
 266            But what .. HPFS.IFS has also bugs in ea management. */
 267         if (le16_to_cpu(fnode->ea_size_s) && !le32_to_cpu(fnode->ea_size_l)) {
 268                 secno n;
 269                 struct buffer_head *bh;
 270                 char *data;
 271                 if (!(n = hpfs_alloc_sector(s, fno, 1, 0))) return;
 272                 if (!(data = hpfs_get_sector(s, n, &bh))) {
 273                         hpfs_free_sectors(s, n, 1);
 274                         return;
 275                 }
 276                 memcpy(data, fnode_ea(fnode), le16_to_cpu(fnode->ea_size_s));
 277                 fnode->ea_size_l = cpu_to_le32(le16_to_cpu(fnode->ea_size_s));
 278                 fnode->ea_size_s = cpu_to_le16(0);
 279                 fnode->ea_secno = cpu_to_le32(n);
 280                 fnode->flags &= ~FNODE_anode;
 281                 mark_buffer_dirty(bh);
 282                 brelse(bh);
 283         }
 284         pos = le32_to_cpu(fnode->ea_size_l) + 5 + strlen(key) + size;
 285         len = (le32_to_cpu(fnode->ea_size_l) + 511) >> 9;
 286         if (pos >= 30000) goto bail;
 287         while (((pos + 511) >> 9) > len) {
 288                 if (!len) {
 289                         secno q = hpfs_alloc_sector(s, fno, 1, 0);
 290                         if (!q) goto bail;
 291                         fnode->ea_secno = cpu_to_le32(q);
 292                         fnode->flags &= ~FNODE_anode;
 293                         len++;
 294                 } else if (!fnode_in_anode(fnode)) {
 295                         if (hpfs_alloc_if_possible(s, le32_to_cpu(fnode->ea_secno) + len)) {
 296                                 len++;
 297                         } else {
 298                                 /* Aargh... don't know how to create ea anodes :-( */
 299                                 /*struct buffer_head *bh;
 300                                 struct anode *anode;
 301                                 anode_secno a_s;
 302                                 if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
 303                                         goto bail;
 304                                 anode->up = cpu_to_le32(fno);
 305                                 anode->btree.fnode_parent = 1;
 306                                 anode->btree.n_free_nodes--;
 307                                 anode->btree.n_used_nodes++;
 308                                 anode->btree.first_free = cpu_to_le16(le16_to_cpu(anode->btree.first_free) + 12);
 309                                 anode->u.external[0].disk_secno = cpu_to_le32(le32_to_cpu(fnode->ea_secno));
 310                                 anode->u.external[0].file_secno = cpu_to_le32(0);
 311                                 anode->u.external[0].length = cpu_to_le32(len);
 312                                 mark_buffer_dirty(bh);
 313                                 brelse(bh);
 314                                 fnode->flags |= FNODE_anode;
 315                                 fnode->ea_secno = cpu_to_le32(a_s);*/
 316                                 secno new_sec;
 317                                 int i;
 318                                 if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9))))
 319                                         goto bail;
 320                                 for (i = 0; i < len; i++) {
 321                                         struct buffer_head *bh1, *bh2;
 322                                         void *b1, *b2;
 323                                         if (!(b1 = hpfs_map_sector(s, le32_to_cpu(fnode->ea_secno) + i, &bh1, len - i - 1))) {
 324                                                 hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 325                                                 goto bail;
 326                                         }
 327                                         if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
 328                                                 brelse(bh1);
 329                                                 hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
 330                                                 goto bail;
 331                                         }
 332                                         memcpy(b2, b1, 512);
 333                                         brelse(bh1);
 334                                         mark_buffer_dirty(bh2);
 335                                         brelse(bh2);
 336                                 }
 337                                 hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno), len);
 338                                 fnode->ea_secno = cpu_to_le32(new_sec);
 339                                 len = (pos + 511) >> 9;
 340                         }
 341                 }
 342                 if (fnode_in_anode(fnode)) {
 343                         if (hpfs_add_sector_to_btree(s, le32_to_cpu(fnode->ea_secno),
 344                                                      0, len) != -1) {
 345                                 len++;
 346                         } else {
 347                                 goto bail;
 348                         }
 349                 }
 350         }
 351         h[0] = 0;
 352         h[1] = strlen(key);
 353         h[2] = size & 0xff;
 354         h[3] = size >> 8;
 355         if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l), 4, h)) goto bail;
 356         if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 4, h[1] + 1, key)) goto bail;
 357         if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 5 + h[1], size, data)) goto bail;
 358         fnode->ea_size_l = cpu_to_le32(pos);
 359         ret:
 360         hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
 361         return;
 362         bail:
 363         if (le32_to_cpu(fnode->ea_secno))
 364                 if (fnode_in_anode(fnode)) hpfs_truncate_btree(s, le32_to_cpu(fnode->ea_secno), 1, (le32_to_cpu(fnode->ea_size_l) + 511) >> 9);
 365                 else hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno) + ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9), len - ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9));
 366         else fnode->ea_secno = fnode->ea_size_l = cpu_to_le32(0);
 367 }
 368