lib/util/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) resemblence to that
  23    code now
  24 */
  25
  26 /**
  27  * @file
  28  * @brief MS-style Filename matching
  29  */
  30
  31 #include "includes.h"
  32 #include "libcli/smb/smb_constants.h"
  33
  34 static int null_match(const char *p)
  35 {
  36         for (;*p;p++) {
  37                 if (*p != '*' &&
  38                     *p != '<' &&
  39                     *p != '"' &&
  40                     *p != '>') return -1;
  41         }
  42         return 0;
  43 }
  44
  45 /*
  46   the max_n structure is purely for efficiency, it doesn't contribute
  47   to the matching algorithm except by ensuring that the algorithm does
  48   not grow exponentially
  49 */
  50 struct max_n {
  51         const char *predot;
  52         const char *postdot;
  53 };
  54
  55
  56 /*
  57   p and n are the pattern and string being matched. The max_n array is
  58   an optimisation only. The ldot pointer is NULL if the string does
  59   not contain a '.', otherwise it points at the last dot in 'n'.
  60 */
  61 static int ms_fnmatch_core(const char *p, const char *n,
  62                            struct max_n *max_n, const char *ldot,
  63                            bool is_case_sensitive)
  64 {
  65         codepoint_t c, c2;
  66         int i;
  67         size_t size, size_n;
  68
  69         while ((c = next_codepoint(p, &size))) {
  70                 p += size;
  71
  72                 switch (c) {
  73                 case '*':
  74                         /* a '*' matches zero or more characters of any type */
  75                         if (max_n != NULL && max_n->predot &&
  76                             max_n->predot <= n) {
  77                                 return null_match(p);
  78                         }
  79                         for (i=0; n[i]; i += size_n) {
  80                                 next_codepoint(n+i, &size_n);
  81                                 if (ms_fnmatch_core(p, n+i, max_n+1, ldot, is_case_sensitive) == 0) {
  82                                         return 0;
  83                                 }
  84                         }
  85                         if (max_n != NULL && (!max_n->predot ||
  86                             max_n->predot > n)) {
  87                                 max_n->predot = n;
  88                         }
  89                         return null_match(p);
  90
  91                 case '<':
  92                         /* a '<' matches zero or more characters of
  93                            any type, but stops matching at the last
  94                            '.' in the string. */
  95                         if (max_n != NULL && max_n->predot &&
  96                             max_n->predot <= n) {
  97                                 return null_match(p);
  98                         }
  99                         if (max_n != NULL && max_n->postdot &&
 100                             max_n->postdot <= n && n <= ldot) {
 101                                 return -1;
 102                         }
 103                         for (i=0; n[i]; i += size_n) {
 104                                 next_codepoint(n+i, &size_n);
 105                                 if (ms_fnmatch_core(p, n+i, max_n+1, ldot, is_case_sensitive) == 0) return 0;
 106                                 if (n+i == ldot) {
 107                                         if (ms_fnmatch_core(p, n+i+size_n, max_n+1, ldot, is_case_sensitive) == 0) return 0;
 108                                         if (max_n != NULL) {
 109                                                 if (!max_n->postdot ||
 110                                                     max_n->postdot > n) {
 111                                                         max_n->postdot = n;
 112                                                 }
 113                                         }
 114                                         return -1;
 115                                 }
 116                         }
 117                         if (max_n != NULL && (!max_n->predot ||
 118                             max_n->predot > n)) {
 119                                 max_n->predot = n;
 120                         }
 121                         return null_match(p);
 122
 123                 case '?':
 124                         /* a '?' matches any single character */
 125                         if (! *n) {
 126                                 return -1;
 127                         }
 128                         next_codepoint(n, &size_n);
 129                         n += size_n;
 130                         break;
 131
 132                 case '>':
 133                         /* a '?' matches any single character, but
 134                            treats '.' specially */
 135                         if (n[0] == '.') {
 136                                 if (! n[1] && null_match(p) == 0) {
 137                                         return 0;
 138                                 }
 139                                 break;
 140                         }
 141                         if (! *n) return null_match(p);
 142                         next_codepoint(n, &size_n);
 143                         n += size_n;
 144                         break;
 145
 146                 case '"':
 147                         /* a bit like a soft '.' */
 148                         if (*n == 0 && null_match(p) == 0) {
 149                                 return 0;
 150                         }
 151                         if (*n != '.') return -1;
 152                         next_codepoint(n, &size_n);
 153                         n += size_n;
 154                         break;
 155
 156                 default:
 157                         c2 = next_codepoint(n, &size_n);
 158                         if (c != c2) {
 159                                 if (is_case_sensitive) {
 160                                         return -1;
 161                                 }
 162                                 if (codepoint_cmpi(c, c2) != 0) {
 163                                         return -1;
 164                                 }
 165                         }
 166                         n += size_n;
 167                         break;
 168                 }
 169         }
 170
 171         if (! *n) {
 172                 return 0;
 173         }
 174
 175         return -1;
 176 }
 177
 178 int ms_fnmatch_protocol(const char *pattern, const char *string, int protocol,
 179                         bool is_case_sensitive)
 180 {
 181         int ret = -1;
 182         size_t count, i;
 183
 184         if (strcmp(string, "..") == 0) {
 185                 string = ".";
 186         }
 187
 188         if (strpbrk(pattern, "<>*?\"") == NULL) {
 189                 /* this is not just an optimisation - it is essential
 190                    for LANMAN1 correctness */
 191                 return strcasecmp_m(pattern, string);
 192         }
 193
 194         if (protocol <= PROTOCOL_LANMAN2) {
 195                 char *p = talloc_strdup(NULL, pattern);
 196                 if (p == NULL) {
 197                         return -1;
 198                 }
 199                 /*
 200                   for older negotiated protocols it is possible to
 201                   translate the pattern to produce a "new style"
 202                   pattern that exactly matches w2k behaviour
 203                 */
 204                 for (i=0;p[i];i++) {
 205                         if (p[i] == '?') {
 206                                 p[i] = '>';
 207                         } else if (p[i] == '.' &&
 208                                    (p[i+1] == '?' ||
 209                                     p[i+1] == '*' ||
 210                                     p[i+1] == 0)) {
 211                                 p[i] = '"';
 212                         } else if (p[i] == '*' &&
 213                                    p[i+1] == '.') {
 214                                 p[i] = '<';
 215                         }
 216                 }
 217                 ret = ms_fnmatch_protocol(p, string, PROTOCOL_NT1,
 218                                           is_case_sensitive);
 219                 talloc_free(p);
 220                 return ret;
 221         }
 222
 223         for (count=i=0;pattern[i];i++) {
 224                 if (pattern[i] == '*' || pattern[i] == '<') count++;
 225         }
 226
 227         /* If the pattern includes '*' or '<' */
 228         if (count >= 1) {
 229                 struct max_n max_n[count];
 230
 231                 memset(max_n, 0, sizeof(struct max_n) * count);
 232
 233                 ret = ms_fnmatch_core(pattern, string, max_n, strrchr(string, '.'),
 234                                       is_case_sensitive);
 235         } else {
 236                 ret = ms_fnmatch_core(pattern, string, NULL, strrchr(string, '.'),
 237                                       is_case_sensitive);
 238         }
 239
 240         return ret;
 241 }
 242
 243
 244 /** a generic fnmatch function - uses for non-CIFS pattern matching */
 245 int gen_fnmatch(const char *pattern, const char *string)
 246 {
 247         return ms_fnmatch_protocol(pattern, string, PROTOCOL_NT1, false);
 248 }