source/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 2 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, write to the Free Software
  18    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 /*
  22    This module was originally based on fnmatch.c copyright by the Free
  23    Software Foundation. It bears little (if any) resemblence to that
  24    code now
  25 */
  26
  27
  28 #include "includes.h"
  29
  30 static int null_match(const smb_ucs2_t *p)
  31 {
  32         for (;*p;p++) {
  33                 if (*p != UCS2_CHAR('*') &&
  34                     *p != UCS2_CHAR('<') &&
  35                     *p != UCS2_CHAR('"') &&
  36                     *p != UCS2_CHAR('>')) return -1;
  37         }
  38         return 0;
  39 }
  40
  41 /*
  42   the max_n structure is purely for efficiency, it doesn't contribute
  43   to the matching algorithm except by ensuring that the algorithm does
  44   not grow exponentially
  45 */
  46 struct max_n {
  47         const smb_ucs2_t *predot;
  48         const smb_ucs2_t *postdot;
  49 };
  50
  51
  52 /*
  53   p and n are the pattern and string being matched. The max_n array is
  54   an optimisation only. The ldot pointer is NULL if the string does
  55   not contain a '.', otherwise it points at the last dot in 'n'.
  56 */
  57 static int ms_fnmatch_core(const smb_ucs2_t *p, const smb_ucs2_t *n,
  58                            struct max_n *max_n, const smb_ucs2_t *ldot,
  59                            BOOL is_case_sensitive)
  60 {
  61         smb_ucs2_t c;
  62         int i;
  63
  64         while ((c = *p++)) {
  65                 switch (c) {
  66                         /* a '*' matches zero or more characters of any type */
  67                 case UCS2_CHAR('*'):
  68                         if (max_n->predot && max_n->predot <= n) {
  69                                 return null_match(p);
  70                         }
  71                         for (i=0; n[i]; i++) {
  72                                 if (ms_fnmatch_core(p, n+i, max_n+1, ldot, is_case_sensitive) == 0) {
  73                                         return 0;
  74                                 }
  75                         }
  76                         if (!max_n->predot || max_n->predot > n) max_n->predot = n;
  77                         return null_match(p);
  78
  79                         /* a '<' matches zero or more characters of
  80                            any type, but stops matching at the last
  81                            '.' in the string. */
  82                 case UCS2_CHAR('<'):
  83                         if (max_n->predot && max_n->predot <= n) {
  84                                 return null_match(p);
  85                         }
  86                         if (max_n->postdot && max_n->postdot <= n && n <= ldot) {
  87                                 return -1;
  88                         }
  89                         for (i=0; n[i]; i++) {
  90                                 if (ms_fnmatch_core(p, n+i, max_n+1, ldot, is_case_sensitive) == 0) return 0;
  91                                 if (n+i == ldot) {
  92                                         if (ms_fnmatch_core(p, n+i+1, max_n+1, ldot, is_case_sensitive) == 0) return 0;
  93                                         if (!max_n->postdot || max_n->postdot > n) max_n->postdot = n;
  94                                         return -1;
  95                                 }
  96                         }
  97                         if (!max_n->predot || max_n->predot > n) max_n->predot = n;
  98                         return null_match(p);
  99
 100                         /* a '?' matches any single character */
 101                 case UCS2_CHAR('?'):
 102                         if (! *n) {
 103                                 return -1;
 104                         }
 105                         n++;
 106                         break;
 107
 108                         /* a '?' matches any single character */
 109                 case UCS2_CHAR('>'):
 110                         if (n[0] == UCS2_CHAR('.')) {
 111                                 if (! n[1] && null_match(p) == 0) {
 112                                         return 0;
 113                                 }
 114                                 break;
 115                         }
 116                         if (! *n) return null_match(p);
 117                         n++;
 118                         break;
 119
 120                 case UCS2_CHAR('"'):
 121                         if (*n == 0 && null_match(p) == 0) {
 122                                 return 0;
 123                         }
 124                         if (*n != UCS2_CHAR('.')) return -1;
 125                         n++;
 126                         break;
 127
 128                 default:
 129                         if (c != *n) {
 130                                 if (is_case_sensitive) {
 131                                         return -1;
 132                                 }
 133                                 if (toupper_w(c) != toupper_w(*n)) {
 134                                         return -1;
 135                                 }
 136                         }
 137                         n++;
 138                         break;
 139                 }
 140         }
 141
 142         if (! *n) {
 143                 return 0;
 144         }
 145
 146         return -1;
 147 }
 148
 149 int ms_fnmatch(const char *pattern, const char *string, BOOL translate_pattern,
 150                BOOL is_case_sensitive)
 151 {
 152         wpstring p, s;
 153         int ret, count, i;
 154         struct max_n *max_n = NULL;
 155
 156         if (strcmp(string, "..") == 0) {
 157                 string = ".";
 158         }
 159
 160         if (strpbrk(pattern, "<>*?\"") == NULL) {
 161                 /* this is not just an optmisation - it is essential
 162                    for LANMAN1 correctness */
 163                 if (is_case_sensitive) {
 164                         return strcmp(pattern, string);
 165                 } else {
 166                         return StrCaseCmp(pattern, string);
 167                 }
 168         }
 169
 170         if (push_ucs2(NULL, p, pattern, sizeof(p), STR_TERMINATE) == (size_t)-1) {
 171                 /* Not quite the right answer, but finding the right one
 172                   under this failure case is expensive, and it's pretty close */
 173                 return -1;
 174         }
 175
 176         if (push_ucs2(NULL, s, string, sizeof(s), STR_TERMINATE) == (size_t)-1) {
 177                 /* Not quite the right answer, but finding the right one
 178                    under this failure case is expensive, and it's pretty close */
 179                 return -1;
 180         }
 181
 182         if (translate_pattern) {
 183                 /*
 184                   for older negotiated protocols it is possible to
 185                   translate the pattern to produce a "new style"
 186                   pattern that exactly matches w2k behaviour
 187                 */
 188                 for (i=0;p[i];i++) {
 189                         if (p[i] == UCS2_CHAR('?')) {
 190                                 p[i] = UCS2_CHAR('>');
 191                         } else if (p[i] == UCS2_CHAR('.') &&
 192                                    (p[i+1] == UCS2_CHAR('?') ||
 193                                     p[i+1] == UCS2_CHAR('*') ||
 194                                     p[i+1] == 0)) {
 195                                 p[i] = UCS2_CHAR('"');
 196                         } else if (p[i] == UCS2_CHAR('*') && p[i+1] == UCS2_CHAR('.')) {
 197                                 p[i] = UCS2_CHAR('<');
 198                         }
 199                 }
 200         }
 201
 202         for (count=i=0;p[i];i++) {
 203                 if (p[i] == UCS2_CHAR('*') || p[i] == UCS2_CHAR('<')) count++;
 204         }
 205
 206         if (count != 0) {
 207                 max_n = SMB_CALLOC_ARRAY(struct max_n, count);
 208                 if (!max_n) {
 209                         return -1;
 210                 }
 211         }
 212
 213         ret = ms_fnmatch_core(p, s, max_n, strrchr_w(s, UCS2_CHAR('.')), is_case_sensitive);
 214
 215         if (max_n) {
 216                 free(max_n);
 217         }
 218
 219         return ret;
 220 }
 221
 222
 223 /* a generic fnmatch function - uses for non-CIFS pattern matching */
 224 int gen_fnmatch(const char *pattern, const char *string)
 225 {
 226         return ms_fnmatch(pattern, string, PROTOCOL_NT1, False);
 227 }