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
  12 static inline int not_allowed_char(unsigned char c)
  13 {
  14         return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
  15               c=='>' || c=='?' || c=='\\' || c=='|';
  16 }
  17
  18 static 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
  23 static 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
  30 unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
  31 {
  32         return upcase(dir, a);
  33 }
  34
  35 static 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
  42 int 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
  54 unsigned 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
  75 int 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
  93 int 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
 107 void 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 }