source3/lib/ms_fnmatch.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    filename matching routine
   4    Copyright (C) Andrew Tridgell 1992-2004
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 /*
  21    This module was originally based on fnmatch.c copyright by the Free
  22    Software Foundation. It bears little (if any) resemblance to that
  23    code now
  24 */
  25
  26
  27 #include "includes.h"
  28
  29 static int null_match(const smb_ucs2_t *p)
  30 {
  31         for (;*p;p++) {
  32                 if (*p != UCS2_CHAR('*') &&
  33                     *p != UCS2_CHAR('<') &&
  34                     *p != UCS2_CHAR('"') &&
  35                     *p != UCS2_CHAR('>')) return -1;
  36         }
  37         return 0;
  38 }
  39
  40 /*
  41   the max_n structure is purely for efficiency, it doesn't contribute
  42   to the matching algorithm except by ensuring that the algorithm does
  43   not grow exponentially
  44 */
  45 struct max_n {
  46         const smb_ucs2_t *predot;
  47         const smb_ucs2_t *postdot;
  48 };
  49
  50
  51 /*
  52   p and n are the pattern and string being matched. The max_n array is
  53   an optimisation only. The ldot pointer is NULL if the string does
  54   not contain a '.', otherwise it points at the last dot in 'n'.
  55 */
  56 static int ms_fnmatch_core(const smb_ucs2_t *p, const smb_ucs2_t *n,
  57                            struct max_n *max_n, const smb_ucs2_t *ldot,
  58                            bool is_case_sensitive)
  59 {
  60         smb_ucs2_t c;
  61         int i;
  62
  63         while ((c = *p++)) {
  64                 switch (c) {
  65                         /* a '*' matches zero or more characters of any type */
  66                 case UCS2_CHAR('*'):
  67                         if (max_n->predot && max_n->predot <= n) {
  68                                 return null_match(p);
  69                         }
  70                         for (i=0; n[i]; i++) {
  71                                 if (ms_fnmatch_core(p, n+i, max_n+1, ldot, is_case_sensitive) == 0) {
  72                                         return 0;
  73                                 }
  74                         }
  75                         if (!max_n->predot || max_n->predot > n) max_n->predot = n;
  76                         return null_match(p);
  77
  78                         /* a '<' matches zero or more characters of
  79                            any type, but stops matching at the last
  80                            '.' in the string. */
  81                 case UCS2_CHAR('<'):
  82                         if (max_n->predot && max_n->predot <= n) {
  83                                 return null_match(p);
  84                         }
  85                         if (max_n->postdot && max_n->postdot <= n && n <= ldot) {
  86                                 return -1;
  87                         }
  88                         for (i=0; n[i]; i++) {
  89                                 if (ms_fnmatch_core(p, n+i, max_n+1, ldot, is_case_sensitive) == 0) return 0;
  90                                 if (n+i == ldot) {
  91                                         if (ms_fnmatch_core(p, n+i+1, max_n+1, ldot, is_case_sensitive) == 0) return 0;
  92                                         if (!max_n->postdot || max_n->postdot > n) max_n->postdot = n;
  93                                         return -1;
  94                                 }
  95                         }
  96                         if (!max_n->predot || max_n->predot > n) max_n->predot = n;
  97                         return null_match(p);
  98
  99                         /* a '?' matches any single character */
 100                 case UCS2_CHAR('?'):
 101                         if (! *n) {
 102                                 return -1;
 103                         }
 104                         n++;
 105                         break;
 106
 107                         /* a '?' matches any single character */
 108                 case UCS2_CHAR('>'):
 109                         if (n[0] == UCS2_CHAR('.')) {
 110                                 if (! n[1] && null_match(p) == 0) {
 111                                         return 0;
 112                                 }
 113                                 break;
 114                         }
 115                         if (! *n) return null_match(p);
 116                         n++;
 117                         break;
 118
 119                 case UCS2_CHAR('"'):
 120                         if (*n == 0 && null_match(p) == 0) {
 121                                 return 0;
 122                         }
 123                         if (*n != UCS2_CHAR('.')) return -1;
 124                         n++;
 125                         break;
 126
 127                 default:
 128                         if (c != *n) {
 129                                 if (is_case_sensitive) {
 130                                         return -1;
 131                                 }
 132                                 if (toupper_w(c) != toupper_w(*n)) {
 133                                         return -1;
 134                                 }
 135                         }
 136                         n++;
 137                         break;
 138                 }
 139         }
 140
 141         if (! *n) {
 142                 return 0;
 143         }
 144
 145         return -1;
 146 }
 147
 148 int ms_fnmatch(const char *pattern, const char *string, bool translate_pattern,
 149                bool is_case_sensitive)
 150 {
 151         smb_ucs2_t *p = NULL;
 152         smb_ucs2_t *s = NULL;
 153         int ret;
 154         size_t count, i;
 155         struct max_n *max_n = NULL;
 156         struct max_n *max_n_free = NULL;
 157         struct max_n one_max_n;
 158         size_t converted_size;
 159
 160         if (ISDOTDOT(string)) {
 161                 string = ".";
 162         }
 163
 164         if (strpbrk(pattern, "<>*?\"") == NULL) {
 165                 /* this is not just an optimisation - it is essential
 166                    for LANMAN1 correctness */
 167                 if (is_case_sensitive) {
 168                         return strcmp(pattern, string);
 169                 } else {
 170                         return strcasecmp_m(pattern, string);
 171                 }
 172         }
 173
 174         if (!push_ucs2_talloc(talloc_tos(), &p, pattern, &converted_size)) {
 175                 return -1;
 176         }
 177
 178         if (!push_ucs2_talloc(talloc_tos(), &s, string, &converted_size)) {
 179                 TALLOC_FREE(p);
 180                 return -1;
 181         }
 182
 183         if (translate_pattern) {
 184                 /*
 185                   for older negotiated protocols it is possible to
 186                   translate the pattern to produce a "new style"
 187                   pattern that exactly matches w2k behaviour
 188                 */
 189                 for (i=0;p[i];i++) {
 190                         if (p[i] == UCS2_CHAR('?')) {
 191                                 p[i] = UCS2_CHAR('>');
 192                         } else if (p[i] == UCS2_CHAR('.') &&
 193                                    (p[i+1] == UCS2_CHAR('?') ||
 194                                     p[i+1] == UCS2_CHAR('*') ||
 195                                     p[i+1] == 0)) {
 196                                 p[i] = UCS2_CHAR('"');
 197                         } else if (p[i] == UCS2_CHAR('*') && p[i+1] == UCS2_CHAR('.')) {
 198                                 p[i] = UCS2_CHAR('<');
 199                         }
 200                 }
 201         }
 202
 203         for (count=i=0;p[i];i++) {
 204                 if (p[i] == UCS2_CHAR('*') || p[i] == UCS2_CHAR('<')) count++;
 205         }
 206
 207         if (count != 0) {
 208                 if (count == 1) {
 209                         /*
 210                          * We're doing this a LOT, so save the effort to allocate
 211                          */
 212                         ZERO_STRUCT(one_max_n);
 213                         max_n = &one_max_n;
 214                 }
 215                 else {
 216                         max_n = SMB_CALLOC_ARRAY(struct max_n, count);
 217                         if (!max_n) {
 218                                 TALLOC_FREE(p);
 219                                 TALLOC_FREE(s);
 220                                 return -1;
 221                         }
 222                         max_n_free = max_n;
 223                 }
 224         }
 225
 226         ret = ms_fnmatch_core(p, s, max_n, strrchr_w(s, UCS2_CHAR('.')), is_case_sensitive);
 227
 228         SAFE_FREE(max_n_free);
 229         TALLOC_FREE(p);
 230         TALLOC_FREE(s);
 231         return ret;
 232 }