fs/hpfs/ea.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  *  linux/fs/hpfs/ea.c
0004  *
0005  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
0006  *
0007  *  handling extended attributes
0008  */
0009
0010 #include "hpfs_fn.h"
0011
0012 /* Remove external extended attributes. ano specifies whether a is a
0013    direct sector where eas starts or an anode */
0014
0015 void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
0016 {
0017     unsigned pos = 0;
0018     while (pos < len) {
0019         char ex[4 + 255 + 1 + 8];
0020         struct extended_attribute *ea = (struct extended_attribute *)ex;
0021         if (pos + 4 > len) {
0022             hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
0023                 ano ? "anode" : "sectors", a, len);
0024             return;
0025         }
0026         if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
0027         if (ea_indirect(ea)) {
0028             if (ea_valuelen(ea) != 8) {
0029                 hpfs_error(s, "ea_indirect(ea) set while ea->valuelen!=8, %s %08x, pos %08x",
0030                     ano ? "anode" : "sectors", a, pos);
0031                 return;
0032             }
0033             if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
0034                 return;
0035             hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
0036         }
0037         pos += ea->namelen + ea_valuelen(ea) + 5;
0038     }
0039     if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
0040     else {
0041         struct buffer_head *bh;
0042         struct anode *anode;
0043         if ((anode = hpfs_map_anode(s, a, &bh))) {
0044             hpfs_remove_btree(s, &anode->btree);
0045             brelse(bh);
0046             hpfs_free_sectors(s, a, 1);
0047         }
0048     }
0049 }
0050
0051 static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
0052 {
0053     char *ret;
0054     if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
0055         pr_err("out of memory for EA\n");
0056         return NULL;
0057     }
0058     if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
0059         kfree(ret);
0060         return NULL;
0061     }
0062     ret[size] = 0;
0063     return ret;
0064 }
0065
0066 static void set_indirect_ea(struct super_block *s, int ano, secno a,
0067                 const char *data, int size)
0068 {
0069     hpfs_ea_write(s, a, ano, 0, size, data);
0070 }
0071
0072 /* Read an extended attribute named 'key' into the provided buffer */
0073
0074 int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
0075         char *buf, int size)
0076 {
0077     unsigned pos;
0078     int ano, len;
0079     secno a;
0080     char ex[4 + 255 + 1 + 8];
0081     struct extended_attribute *ea;
0082     struct extended_attribute *ea_end = fnode_end_ea(fnode);
0083     for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
0084         if (!strcmp(ea->name, key)) {
0085             if (ea_indirect(ea))
0086                 goto indirect;
0087             if (ea_valuelen(ea) >= size)
0088                 return -EINVAL;
0089             memcpy(buf, ea_data(ea), ea_valuelen(ea));
0090             buf[ea_valuelen(ea)] = 0;
0091             return 0;
0092         }
0093     a = le32_to_cpu(fnode->ea_secno);
0094     len = le32_to_cpu(fnode->ea_size_l);
0095     ano = fnode_in_anode(fnode);
0096     pos = 0;
0097     while (pos < len) {
0098         ea = (struct extended_attribute *)ex;
0099         if (pos + 4 > len) {
0100             hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
0101                 ano ? "anode" : "sectors", a, len);
0102             return -EIO;
0103         }
0104         if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
0105         if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
0106             return -EIO;
0107         if (!strcmp(ea->name, key)) {
0108             if (ea_indirect(ea))
0109                 goto indirect;
0110             if (ea_valuelen(ea) >= size)
0111                 return -EINVAL;
0112             if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), buf))
0113                 return -EIO;
0114             buf[ea_valuelen(ea)] = 0;
0115             return 0;
0116         }
0117         pos += ea->namelen + ea_valuelen(ea) + 5;
0118     }
0119     return -ENOENT;
0120 indirect:
0121     if (ea_len(ea) >= size)
0122         return -EINVAL;
0123     if (hpfs_ea_read(s, ea_sec(ea), ea_in_anode(ea), 0, ea_len(ea), buf))
0124         return -EIO;
0125     buf[ea_len(ea)] = 0;
0126     return 0;
0127 }
0128
0129 /* Read an extended attribute named 'key' */
0130 char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
0131 {
0132     char *ret;
0133     unsigned pos;
0134     int ano, len;
0135     secno a;
0136     struct extended_attribute *ea;
0137     struct extended_attribute *ea_end = fnode_end_ea(fnode);
0138     for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
0139         if (!strcmp(ea->name, key)) {
0140             if (ea_indirect(ea))
0141                 return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
0142             if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
0143                 pr_err("out of memory for EA\n");
0144                 return NULL;
0145             }
0146             memcpy(ret, ea_data(ea), ea_valuelen(ea));
0147             ret[ea_valuelen(ea)] = 0;
0148             return ret;
0149         }
0150     a = le32_to_cpu(fnode->ea_secno);
0151     len = le32_to_cpu(fnode->ea_size_l);
0152     ano = fnode_in_anode(fnode);
0153     pos = 0;
0154     while (pos < len) {
0155         char ex[4 + 255 + 1 + 8];
0156         ea = (struct extended_attribute *)ex;
0157         if (pos + 4 > len) {
0158             hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
0159                 ano ? "anode" : "sectors", a, len);
0160             return NULL;
0161         }
0162         if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
0163         if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
0164             return NULL;
0165         if (!strcmp(ea->name, key)) {
0166             if (ea_indirect(ea))
0167                 return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
0168             if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
0169                 pr_err("out of memory for EA\n");
0170                 return NULL;
0171             }
0172             if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), ret)) {
0173                 kfree(ret);
0174                 return NULL;
0175             }
0176             ret[ea_valuelen(ea)] = 0;
0177             return ret;
0178         }
0179         pos += ea->namelen + ea_valuelen(ea) + 5;
0180     }
0181     return NULL;
0182 }
0183
0184 /*
0185  * Update or create extended attribute 'key' with value 'data'. Note that
0186  * when this ea exists, it MUST have the same size as size of data.
0187  * This driver can't change sizes of eas ('cause I just don't need it).
0188  */
0189
0190 void hpfs_set_ea(struct inode *inode, struct fnode *fnode, const char *key,
0191          const char *data, int size)
0192 {
0193     fnode_secno fno = inode->i_ino;
0194     struct super_block *s = inode->i_sb;
0195     unsigned pos;
0196     int ano, len;
0197     secno a;
0198     unsigned char h[4];
0199     struct extended_attribute *ea;
0200     struct extended_attribute *ea_end = fnode_end_ea(fnode);
0201     for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
0202         if (!strcmp(ea->name, key)) {
0203             if (ea_indirect(ea)) {
0204                 if (ea_len(ea) == size)
0205                     set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
0206             } else if (ea_valuelen(ea) == size) {
0207                 memcpy(ea_data(ea), data, size);
0208             }
0209             return;
0210         }
0211     a = le32_to_cpu(fnode->ea_secno);
0212     len = le32_to_cpu(fnode->ea_size_l);
0213     ano = fnode_in_anode(fnode);
0214     pos = 0;
0215     while (pos < len) {
0216         char ex[4 + 255 + 1 + 8];
0217         ea = (struct extended_attribute *)ex;
0218         if (pos + 4 > len) {
0219             hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
0220                 ano ? "anode" : "sectors", a, len);
0221             return;
0222         }
0223         if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
0224         if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
0225             return;
0226         if (!strcmp(ea->name, key)) {
0227             if (ea_indirect(ea)) {
0228                 if (ea_len(ea) == size)
0229                     set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
0230             }
0231             else {
0232                 if (ea_valuelen(ea) == size)
0233                     hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
0234             }
0235             return;
0236         }
0237         pos += ea->namelen + ea_valuelen(ea) + 5;
0238     }
0239     if (!le16_to_cpu(fnode->ea_offs)) {
0240         /*if (le16_to_cpu(fnode->ea_size_s)) {
0241             hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
0242                 inode->i_ino, le16_to_cpu(fnode->ea_size_s));
0243             return;
0244         }*/
0245         fnode->ea_offs = cpu_to_le16(0xc4);
0246     }
0247     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) {
0248         hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
0249             (unsigned long)inode->i_ino,
0250             le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
0251         return;
0252     }
0253     if ((le16_to_cpu(fnode->ea_size_s) || !le32_to_cpu(fnode->ea_size_l)) &&
0254          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) {
0255         ea = fnode_end_ea(fnode);
0256         *(char *)ea = 0;
0257         ea->namelen = strlen(key);
0258         ea->valuelen_lo = size;
0259         ea->valuelen_hi = size >> 8;
0260         strcpy(ea->name, key);
0261         memcpy(ea_data(ea), data, size);
0262         fnode->ea_size_s = cpu_to_le16(le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5);
0263         goto ret;
0264     }
0265     /* Most the code here is 99.9993422% unused. I hope there are no bugs.
0266        But what .. HPFS.IFS has also bugs in ea management. */
0267     if (le16_to_cpu(fnode->ea_size_s) && !le32_to_cpu(fnode->ea_size_l)) {
0268         secno n;
0269         struct buffer_head *bh;
0270         char *data;
0271         if (!(n = hpfs_alloc_sector(s, fno, 1, 0))) return;
0272         if (!(data = hpfs_get_sector(s, n, &bh))) {
0273             hpfs_free_sectors(s, n, 1);
0274             return;
0275         }
0276         memcpy(data, fnode_ea(fnode), le16_to_cpu(fnode->ea_size_s));
0277         fnode->ea_size_l = cpu_to_le32(le16_to_cpu(fnode->ea_size_s));
0278         fnode->ea_size_s = cpu_to_le16(0);
0279         fnode->ea_secno = cpu_to_le32(n);
0280         fnode->flags &= ~FNODE_anode;
0281         mark_buffer_dirty(bh);
0282         brelse(bh);
0283     }
0284     pos = le32_to_cpu(fnode->ea_size_l) + 5 + strlen(key) + size;
0285     len = (le32_to_cpu(fnode->ea_size_l) + 511) >> 9;
0286     if (pos >= 30000) goto bail;
0287     while (((pos + 511) >> 9) > len) {
0288         if (!len) {
0289             secno q = hpfs_alloc_sector(s, fno, 1, 0);
0290             if (!q) goto bail;
0291             fnode->ea_secno = cpu_to_le32(q);
0292             fnode->flags &= ~FNODE_anode;
0293             len++;
0294         } else if (!fnode_in_anode(fnode)) {
0295             if (hpfs_alloc_if_possible(s, le32_to_cpu(fnode->ea_secno) + len)) {
0296                 len++;
0297             } else {
0298                 /* Aargh... don't know how to create ea anodes :-( */
0299                 /*struct buffer_head *bh;
0300                 struct anode *anode;
0301                 anode_secno a_s;
0302                 if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
0303                     goto bail;
0304                 anode->up = cpu_to_le32(fno);
0305                 anode->btree.fnode_parent = 1;
0306                 anode->btree.n_free_nodes--;
0307                 anode->btree.n_used_nodes++;
0308                 anode->btree.first_free = cpu_to_le16(le16_to_cpu(anode->btree.first_free) + 12);
0309                 anode->u.external[0].disk_secno = cpu_to_le32(le32_to_cpu(fnode->ea_secno));
0310                 anode->u.external[0].file_secno = cpu_to_le32(0);
0311                 anode->u.external[0].length = cpu_to_le32(len);
0312                 mark_buffer_dirty(bh);
0313                 brelse(bh);
0314                 fnode->flags |= FNODE_anode;
0315                 fnode->ea_secno = cpu_to_le32(a_s);*/
0316                 secno new_sec;
0317                 int i;
0318                 if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9))))
0319                     goto bail;
0320                 for (i = 0; i < len; i++) {
0321                     struct buffer_head *bh1, *bh2;
0322                     void *b1, *b2;
0323                     if (!(b1 = hpfs_map_sector(s, le32_to_cpu(fnode->ea_secno) + i, &bh1, len - i - 1))) {
0324                         hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
0325                         goto bail;
0326                     }
0327                     if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
0328                         brelse(bh1);
0329                         hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
0330                         goto bail;
0331                     }
0332                     memcpy(b2, b1, 512);
0333                     brelse(bh1);
0334                     mark_buffer_dirty(bh2);
0335                     brelse(bh2);
0336                 }
0337                 hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno), len);
0338                 fnode->ea_secno = cpu_to_le32(new_sec);
0339                 len = (pos + 511) >> 9;
0340             }
0341         }
0342         if (fnode_in_anode(fnode)) {
0343             if (hpfs_add_sector_to_btree(s, le32_to_cpu(fnode->ea_secno),
0344                              0, len) != -1) {
0345                 len++;
0346             } else {
0347                 goto bail;
0348             }
0349         }
0350     }
0351     h[0] = 0;
0352     h[1] = strlen(key);
0353     h[2] = size & 0xff;
0354     h[3] = size >> 8;
0355     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;
0356     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;
0357     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;
0358     fnode->ea_size_l = cpu_to_le32(pos);
0359     ret:
0360     hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
0361     return;
0362     bail:
0363     if (le32_to_cpu(fnode->ea_secno))
0364         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);
0365         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));
0366     else fnode->ea_secno = fnode->ea_size_l = cpu_to_le32(0);
0367 }
0368