LXR linux/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
  15void 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
  51static 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
  66static 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
  74int 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;
 120indirect:
 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' */
 130char *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
 190void 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        
 369