LXR linux/fs/hpfs/name.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  linux/fs/hpfs/name.c
   4 *
   5 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   6 *
   7 *  operations with filenames
   8 */
   9
  10#include "hpfs_fn.h"
  11
  12static inline int not_allowed_char(unsigned char c)
  13{
  14        return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
  15              c=='>' || c=='?' || c=='\\' || c=='|';
  16}
  17
  18static inline int no_dos_char(unsigned char c)
  19{       /* Characters that are allowed in HPFS but not in DOS */
  20        return c=='+' || c==',' || c==';' || c=='=' || c=='[' || c==']';
  21}
  22
  23static inline unsigned char upcase(unsigned char *dir, unsigned char a)
  24{
  25        if (a<128 || a==255) return a>='a' && a<='z' ? a - 0x20 : a;
  26        if (!dir) return a;
  27        return dir[a-128];
  28}
  29
  30unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
  31{
  32        return upcase(dir, a);
  33}
  34
  35static inline unsigned char locase(unsigned char *dir, unsigned char a)
  36{
  37        if (a<128 || a==255) return a>='A' && a<='Z' ? a + 0x20 : a;
  38        if (!dir) return a;
  39        return dir[a];
  40}
  41
  42int hpfs_chk_name(const unsigned char *name, unsigned *len)
  43{
  44        int i;
  45        if (*len > 254) return -ENAMETOOLONG;
  46        hpfs_adjust_length(name, len);
  47        if (!*len) return -EINVAL;
  48        for (i = 0; i < *len; i++) if (not_allowed_char(name[i])) return -EINVAL;
  49        if (*len == 1) if (name[0] == '.') return -EINVAL;
  50        if (*len == 2) if (name[0] == '.' && name[1] == '.') return -EINVAL;
  51        return 0;
  52}
  53
  54unsigned char *hpfs_translate_name(struct super_block *s, unsigned char *from,
  55                          unsigned len, int lc, int lng)
  56{
  57        unsigned char *to;
  58        int i;
  59        if (hpfs_sb(s)->sb_chk >= 2) if (hpfs_is_name_long(from, len) != lng) {
  60                pr_err("Long name flag mismatch - name ");
  61                for (i = 0; i < len; i++)
  62                        pr_cont("%c", from[i]);
  63                pr_cont(" misidentified as %s.\n", lng ? "short" : "long");
  64                pr_err("It's nothing serious. It could happen because of bug in OS/2.\nSet checks=normal to disable this message.\n");
  65        }
  66        if (!lc) return from;
  67        if (!(to = kmalloc(len, GFP_KERNEL))) {
  68                pr_err("can't allocate memory for name conversion buffer\n");
  69                return from;
  70        }
  71        for (i = 0; i < len; i++) to[i] = locase(hpfs_sb(s)->sb_cp_table,from[i]);
  72        return to;
  73}
  74
  75int hpfs_compare_names(struct super_block *s,
  76                       const unsigned char *n1, unsigned l1,
  77                       const unsigned char *n2, unsigned l2, int last)
  78{
  79        unsigned l = l1 < l2 ? l1 : l2;
  80        unsigned i;
  81        if (last) return -1;
  82        for (i = 0; i < l; i++) {
  83                unsigned char c1 = upcase(hpfs_sb(s)->sb_cp_table,n1[i]);
  84                unsigned char c2 = upcase(hpfs_sb(s)->sb_cp_table,n2[i]);
  85                if (c1 < c2) return -1;
  86                if (c1 > c2) return 1;
  87        }
  88        if (l1 < l2) return -1;
  89        if (l1 > l2) return 1;
  90        return 0;
  91}
  92
  93int hpfs_is_name_long(const unsigned char *name, unsigned len)
  94{
  95        int i,j;
  96        for (i = 0; i < len && name[i] != '.'; i++)
  97                if (no_dos_char(name[i])) return 1;
  98        if (!i || i > 8) return 1;
  99        if (i == len) return 0;
 100        for (j = i + 1; j < len; j++)
 101                if (name[j] == '.' || no_dos_char(name[i])) return 1;
 102        return j - i > 4;
 103}
 104
 105/* OS/2 clears dots and spaces at the end of file name, so we have to */
 106
 107void hpfs_adjust_length(const unsigned char *name, unsigned *len)
 108{
 109        if (!*len) return;
 110        if (*len == 1 && name[0] == '.') return;
 111        if (*len == 2 && name[0] == '.' && name[1] == '.') return;
 112        while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
 113                (*len)--;
 114}
 115