source: branches/samba-3.2.x/source/smbd/mangle_hash.c

Last change on this file was 133, checked in by Paul Smedley, 17 years ago

Update trunk to 3.2.0pre3
File size: 18.0 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3 Name mangling
4 Copyright (C) Andrew Tridgell 1992-2002
5 Copyright (C) Simo Sorce 2001
6 Copyright (C) Andrew Bartlett 2002
7 Copyright (C) Jeremy Allison 2007
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>.
21*/
22
23#include "includes.h"
24
25/* -------------------------------------------------------------------------- **
26 * Other stuff...
27 *
28 * magic_char - This is the magic char used for mangling. It's
29 * global. There is a call to lp_magicchar() in server.c
30 * that is used to override the initial value.
31 *
32 * MANGLE_BASE - This is the number of characters we use for name mangling.
33 *
34 * basechars - The set characters used for name mangling. This
35 * is static (scope is this file only).
36 *
37 * mangle() - Macro used to select a character from basechars (i.e.,
38 * mangle(n) will return the nth digit, modulo MANGLE_BASE).
39 *
40 * chartest - array 0..255. The index range is the set of all possible
41 * values of a byte. For each byte value, the content is a
42 * two nibble pair. See BASECHAR_MASK below.
43 *
44 * ct_initialized - False until the chartest array has been initialized via
45 * a call to init_chartest().
46 *
47 * BASECHAR_MASK - Masks the upper nibble of a one-byte value.
48 *
49 * isbasecahr() - Given a character, check the chartest array to see
50 * if that character is in the basechars set. This is
51 * faster than using strchr_m().
52 *
53 */
54
55static char magic_char = '~';
56
57static const char basechars[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_-!@#$%";
58#define MANGLE_BASE (sizeof(basechars)/sizeof(char)-1)
59
60static unsigned char *chartest;
61
62#define mangle(V) ((char)(basechars[(V) % MANGLE_BASE]))
63#define BASECHAR_MASK 0xf0
64#define isbasechar(C) ( (chartest[ ((C) & 0xff) ]) & BASECHAR_MASK )
65
66static TDB_CONTEXT *tdb_mangled_cache;
67
68/* -------------------------------------------------------------------- */
69
70static NTSTATUS has_valid_83_chars(const smb_ucs2_t *s, bool allow_wildcards)
71{
72 if (!*s) {
73 return NT_STATUS_INVALID_PARAMETER;
74 }
75
76 if (!allow_wildcards && ms_has_wild_w(s)) {
77 return NT_STATUS_UNSUCCESSFUL;
78 }
79
80 while (*s) {
81 if(!isvalid83_w(*s)) {
82 return NT_STATUS_UNSUCCESSFUL;
83 }
84 s++;
85 }
86
87 return NT_STATUS_OK;
88}
89
90static NTSTATUS has_illegal_chars(const smb_ucs2_t *s, bool allow_wildcards)
91{
92 if (!allow_wildcards && ms_has_wild_w(s)) {
93 return NT_STATUS_UNSUCCESSFUL;
94 }
95
96 while (*s) {
97 if (*s <= 0x1f) {
98 /* Control characters. */
99 return NT_STATUS_UNSUCCESSFUL;
100 }
101 switch(*s) {
102 case UCS2_CHAR('\\'):
103 case UCS2_CHAR('/'):
104 case UCS2_CHAR('|'):
105 case UCS2_CHAR(':'):
106 return NT_STATUS_UNSUCCESSFUL;
107 }
108 s++;
109 }
110
111 return NT_STATUS_OK;
112}
113
114/* return False if something fail and
115 * return 2 alloced unicode strings that contain prefix and extension
116 */
117
118static NTSTATUS mangle_get_prefix(const smb_ucs2_t *ucs2_string, smb_ucs2_t **prefix,
119 smb_ucs2_t **extension, bool allow_wildcards)
120{
121 size_t ext_len;
122 smb_ucs2_t *p;
123
124 *extension = 0;
125 *prefix = strdup_w(ucs2_string);
126 if (!*prefix) {
127 return NT_STATUS_NO_MEMORY;
128 }
129 if ((p = strrchr_w(*prefix, UCS2_CHAR('.')))) {
130 ext_len = strlen_w(p+1);
131 if ((ext_len > 0) && (ext_len < 4) && (p != *prefix) &&
132 (NT_STATUS_IS_OK(has_valid_83_chars(p+1,allow_wildcards)))) /* check extension */ {
133 *p = 0;
134 *extension = strdup_w(p+1);
135 if (!*extension) {
136 SAFE_FREE(*prefix);
137 return NT_STATUS_NO_MEMORY;
138 }
139 }
140 }
141 return NT_STATUS_OK;
142}
143
144/* ************************************************************************** **
145 * Return NT_STATUS_UNSUCCESSFUL if a name is a special msdos reserved name.
146 * or contains illegal characters.
147 *
148 * Input: fname - String containing the name to be tested.
149 *
150 * Output: NT_STATUS_UNSUCCESSFUL, if the condition above is true.
151 *
152 * Notes: This is a static function called by is_8_3(), below.
153 *
154 * ************************************************************************** **
155 */
156
157static NTSTATUS is_valid_name(const smb_ucs2_t *fname, bool allow_wildcards, bool only_8_3)
158{
159 smb_ucs2_t *str, *p;
160 size_t num_ucs2_chars;
161 NTSTATUS ret = NT_STATUS_OK;
162
163 if (!fname || !*fname)
164 return NT_STATUS_INVALID_PARAMETER;
165
166 /* . and .. are valid names. */
167 if (strcmp_wa(fname, ".")==0 || strcmp_wa(fname, "..")==0)
168 return NT_STATUS_OK;
169
170 if (only_8_3) {
171 ret = has_valid_83_chars(fname, allow_wildcards);
172 if (!NT_STATUS_IS_OK(ret))
173 return ret;
174 }
175
176 ret = has_illegal_chars(fname, allow_wildcards);
177 if (!NT_STATUS_IS_OK(ret))
178 return ret;
179
180 /* Name can't end in '.' or ' ' */
181 num_ucs2_chars = strlen_w(fname);
182 if (fname[num_ucs2_chars-1] == UCS2_CHAR('.') || fname[num_ucs2_chars-1] == UCS2_CHAR(' ')) {
183 return NT_STATUS_UNSUCCESSFUL;
184 }
185
186 str = strdup_w(fname);
187
188 /* Truncate copy after the first dot. */
189 p = strchr_w(str, UCS2_CHAR('.'));
190 if (p) {
191 *p = 0;
192 }
193
194 strupper_w(str);
195 p = &str[1];
196
197 switch(str[0])
198 {
199 case UCS2_CHAR('A'):
200 if(strcmp_wa(p, "UX") == 0)
201 ret = NT_STATUS_UNSUCCESSFUL;
202 break;
203 case UCS2_CHAR('C'):
204 if((strcmp_wa(p, "LOCK$") == 0)
205 || (strcmp_wa(p, "ON") == 0)
206 || (strcmp_wa(p, "OM1") == 0)
207 || (strcmp_wa(p, "OM2") == 0)
208 || (strcmp_wa(p, "OM3") == 0)
209 || (strcmp_wa(p, "OM4") == 0)
210 )
211 ret = NT_STATUS_UNSUCCESSFUL;
212 break;
213 case UCS2_CHAR('L'):
214 if((strcmp_wa(p, "PT1") == 0)
215 || (strcmp_wa(p, "PT2") == 0)
216 || (strcmp_wa(p, "PT3") == 0)
217 )
218 ret = NT_STATUS_UNSUCCESSFUL;
219 break;
220 case UCS2_CHAR('N'):
221 if(strcmp_wa(p, "UL") == 0)
222 ret = NT_STATUS_UNSUCCESSFUL;
223 break;
224 case UCS2_CHAR('P'):
225 if(strcmp_wa(p, "RN") == 0)
226 ret = NT_STATUS_UNSUCCESSFUL;
227 break;
228 default:
229 break;
230 }
231
232 SAFE_FREE(str);
233 return ret;
234}
235
236static NTSTATUS is_8_3_w(const smb_ucs2_t *fname, bool allow_wildcards)
237{
238 smb_ucs2_t *pref = 0, *ext = 0;
239 size_t plen;
240 NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
241
242 if (!fname || !*fname)
243 return NT_STATUS_INVALID_PARAMETER;
244
245 if (strlen_w(fname) > 12)
246 return NT_STATUS_UNSUCCESSFUL;
247
248 if (strcmp_wa(fname, ".") == 0 || strcmp_wa(fname, "..") == 0)
249 return NT_STATUS_OK;
250
251 /* Name cannot start with '.' */
252 if (*fname == UCS2_CHAR('.'))
253 return NT_STATUS_UNSUCCESSFUL;
254
255 if (!NT_STATUS_IS_OK(is_valid_name(fname, allow_wildcards, True)))
256 goto done;
257
258 if (!NT_STATUS_IS_OK(mangle_get_prefix(fname, &pref, &ext, allow_wildcards)))
259 goto done;
260 plen = strlen_w(pref);
261
262 if (strchr_wa(pref, '.'))
263 goto done;
264 if (plen < 1 || plen > 8)
265 goto done;
266 if (ext && (strlen_w(ext) > 3))
267 goto done;
268
269 ret = NT_STATUS_OK;
270
271done:
272 SAFE_FREE(pref);
273 SAFE_FREE(ext);
274 return ret;
275}
276
277static bool is_8_3(const char *fname, bool check_case, bool allow_wildcards,
278 const struct share_params *p)
279{
280 const char *f;
281 smb_ucs2_t *ucs2name;
282 NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
283 size_t size;
284
285 magic_char = lp_magicchar(p);
286
287 if (!fname || !*fname)
288 return False;
289 if ((f = strrchr(fname, '/')) == NULL)
290 f = fname;
291 else
292 f++;
293
294 if (strlen(f) > 12)
295 return False;
296
297 size = push_ucs2_allocate(&ucs2name, f);
298 if (size == (size_t)-1) {
299 DEBUG(0,("is_8_3: internal error push_ucs2_allocate() failed!\n"));
300 goto done;
301 }
302
303 ret = is_8_3_w(ucs2name, allow_wildcards);
304
305done:
306 SAFE_FREE(ucs2name);
307
308 if (!NT_STATUS_IS_OK(ret)) {
309 return False;
310 }
311
312 return True;
313}
314
315/* -------------------------------------------------------------------------- **
316 * Functions...
317 */
318
319/* ************************************************************************** **
320 * Initialize the static character test array.
321 *
322 * Input: none
323 *
324 * Output: none
325 *
326 * Notes: This function changes (loads) the contents of the <chartest>
327 * array. The scope of <chartest> is this file.
328 *
329 * ************************************************************************** **
330 */
331
332static void init_chartest( void )
333{
334 const unsigned char *s;
335
336 chartest = SMB_MALLOC_ARRAY(unsigned char, 256);
337
338 SMB_ASSERT(chartest != NULL);
339
340 for( s = (const unsigned char *)basechars; *s; s++ ) {
341 chartest[*s] |= BASECHAR_MASK;
342 }
343}
344
345/* ************************************************************************** **
346 * Return True if the name *could be* a mangled name.
347 *
348 * Input: s - A path name - in UNIX pathname format.
349 *
350 * Output: True if the name matches the pattern described below in the
351 * notes, else False.
352 *
353 * Notes: The input name is *not* tested for 8.3 compliance. This must be
354 * done separately. This function returns true if the name contains
355 * a magic character followed by excactly two characters from the
356 * basechars list (above), which in turn are followed either by the
357 * nul (end of string) byte or a dot (extension) or by a '/' (end of
358 * a directory name).
359 *
360 * ************************************************************************** **
361 */
362
363static bool is_mangled(const char *s, const struct share_params *p)
364{
365 char *magic;
366
367 magic_char = lp_magicchar(p);
368
369 if (chartest == NULL) {
370 init_chartest();
371 }
372
373 magic = strchr_m( s, magic_char );
374 while( magic && magic[1] && magic[2] ) { /* 3 chars, 1st is magic. */
375 if( ('.' == magic[3] || '/' == magic[3] || !(magic[3])) /* Ends with '.' or nul or '/' ? */
376 && isbasechar( toupper_ascii(magic[1]) ) /* is 2nd char basechar? */
377 && isbasechar( toupper_ascii(magic[2]) ) ) /* is 3rd char basechar? */
378 return( True ); /* If all above, then true, */
379 magic = strchr_m( magic+1, magic_char ); /* else seek next magic. */
380 }
381 return( False );
382}
383
384/***************************************************************************
385 Initializes or clears the mangled cache.
386***************************************************************************/
387
388static void mangle_reset( void )
389{
390 /* We could close and re-open the tdb here... should we ? The old code did
391 the equivalent... JRA. */
392}
393
394/***************************************************************************
395 Add a mangled name into the cache.
396 If the extension of the raw name maps directly to the
397 extension of the mangled name, then we'll store both names
398 *without* extensions. That way, we can provide consistent
399 reverse mangling for all names that match. The test here is
400 a bit more careful than the one done in earlier versions of
401 mangle.c:
402
403 - the extension must exist on the raw name,
404 - it must be all lower case
405 - it must match the mangled extension (to prove that no
406 mangling occurred).
407 crh 07-Apr-1998
408**************************************************************************/
409
410static void cache_mangled_name( const char mangled_name[13],
411 const char *raw_name )
412{
413 TDB_DATA data_val;
414 char mangled_name_key[13];
415 char *s1;
416 char *s2;
417
418 /* If the cache isn't initialized, give up. */
419 if( !tdb_mangled_cache )
420 return;
421
422 /* Init the string lengths. */
423 safe_strcpy(mangled_name_key, mangled_name, sizeof(mangled_name_key)-1);
424
425 /* See if the extensions are unmangled. If so, store the entry
426 * without the extension, thus creating a "group" reverse map.
427 */
428 s1 = strrchr( mangled_name_key, '.' );
429 if( s1 && (s2 = strrchr( raw_name, '.' )) ) {
430 size_t i = 1;
431 while( s1[i] && (tolower_ascii( s1[i] ) == s2[i]) )
432 i++;
433 if( !s1[i] && !s2[i] ) {
434 /* Truncate at the '.' */
435 *s1 = '\0';
436 *s2 = '\0';
437 }
438 }
439
440 /* Allocate a new cache entry. If the allocation fails, just return. */
441 data_val = string_term_tdb_data(raw_name);
442 if (tdb_store_bystring(tdb_mangled_cache, mangled_name_key, data_val, TDB_REPLACE) != 0) {
443 DEBUG(0,("cache_mangled_name: Error storing entry %s -> %s\n", mangled_name_key, raw_name));
444 } else {
445 DEBUG(5,("cache_mangled_name: Stored entry %s -> %s\n", mangled_name_key, raw_name));
446 }
447}
448
449/* ************************************************************************** **
450 * Check for a name on the mangled name stack
451 *
452 * Input: s - Input *and* output string buffer.
453 * maxlen - space in i/o string buffer.
454 * Output: True if the name was found in the cache, else False.
455 *
456 * Notes: If a reverse map is found, the function will overwrite the string
457 * space indicated by the input pointer <s>. This is frightening.
458 * It should be rewritten to return NULL if the long name was not
459 * found, and a pointer to the long name if it was found.
460 *
461 * ************************************************************************** **
462 */
463
464static bool lookup_name_from_8_3(TALLOC_CTX *ctx,
465 const char *in,
466 char **out, /* talloced on the given context. */
467 const struct share_params *p)
468{
469 TDB_DATA data_val;
470 char *saved_ext = NULL;
471 char *s = talloc_strdup(ctx, in);
472
473 magic_char = lp_magicchar(p);
474
475 /* If the cache isn't initialized, give up. */
476 if(!s || !tdb_mangled_cache ) {
477 TALLOC_FREE(s);
478 return False;
479 }
480
481 data_val = tdb_fetch_bystring(tdb_mangled_cache, s);
482
483 /* If we didn't find the name *with* the extension, try without. */
484 if(data_val.dptr == NULL || data_val.dsize == 0) {
485 char *ext_start = strrchr( s, '.' );
486 if( ext_start ) {
487 if((saved_ext = talloc_strdup(ctx,ext_start)) == NULL) {
488 TALLOC_FREE(s);
489 return False;
490 }
491
492 *ext_start = '\0';
493 data_val = tdb_fetch_bystring(tdb_mangled_cache, s);
494 /*
495 * At this point s is the name without the
496 * extension. We re-add the extension if saved_ext
497 * is not null, before freeing saved_ext.
498 */
499 }
500 }
501
502 /* Okay, if we haven't found it we're done. */
503 if(data_val.dptr == NULL || data_val.dsize == 0) {
504 TALLOC_FREE(saved_ext);
505 TALLOC_FREE(s);
506 return False;
507 }
508
509 /* If we *did* find it, we need to talloc it on the given ctx. */
510 if (saved_ext) {
511 *out = talloc_asprintf(ctx, "%s%s",
512 (char *)data_val.dptr,
513 saved_ext);
514 } else {
515 *out = talloc_strdup(ctx, (char *)data_val.dptr);
516 }
517
518 TALLOC_FREE(s);
519 TALLOC_FREE(saved_ext);
520 SAFE_FREE(data_val.dptr);
521
522 return *out ? True : False;
523}
524
525/*****************************************************************************
526 Do the actual mangling to 8.3 format.
527*****************************************************************************/
528
529static bool to_8_3(const char *in, char out[13], int default_case)
530{
531 int csum;
532 char *p;
533 char extension[4];
534 char base[9];
535 int baselen = 0;
536 int extlen = 0;
537 char *s = SMB_STRDUP(in);
538
539 extension[0] = 0;
540 base[0] = 0;
541
542 if (!s) {
543 return False;
544 }
545
546 p = strrchr(s,'.');
547 if( p && (strlen(p+1) < (size_t)4) ) {
548 bool all_normal = ( strisnormal(p+1, default_case) ); /* XXXXXXXXX */
549
550 if( all_normal && p[1] != 0 ) {
551 *p = 0;
552 csum = str_checksum( s );
553 *p = '.';
554 } else
555 csum = str_checksum(s);
556 } else
557 csum = str_checksum(s);
558
559 strupper_m( s );
560
561 if( p ) {
562 if( p == s )
563 safe_strcpy( extension, "___", 3 );
564 else {
565 *p++ = 0;
566 while( *p && extlen < 3 ) {
567 if ( *p != '.') {
568 extension[extlen++] = p[0];
569 }
570 p++;
571 }
572 extension[extlen] = 0;
573 }
574 }
575
576 p = s;
577
578 while( *p && baselen < 5 ) {
579 if (isbasechar(*p)) {
580 base[baselen++] = p[0];
581 }
582 p++;
583 }
584 base[baselen] = 0;
585
586 csum = csum % (MANGLE_BASE*MANGLE_BASE);
587
588 memcpy(out, base, baselen);
589 out[baselen] = magic_char;
590 out[baselen+1] = mangle( csum/MANGLE_BASE );
591 out[baselen+2] = mangle( csum );
592
593 if( *extension ) {
594 out[baselen+3] = '.';
595 safe_strcpy(&out[baselen+4], extension, 3);
596 }
597
598 SAFE_FREE(s);
599 return True;
600}
601
602static bool must_mangle(const char *name,
603 const struct share_params *p)
604{
605 smb_ucs2_t *name_ucs2 = NULL;
606 NTSTATUS status;
607 magic_char = lp_magicchar(p);
608
609 if (push_ucs2_allocate(&name_ucs2, name) == (size_t)-1) {
610 DEBUG(0, ("push_ucs2_allocate failed!\n"));
611 return False;
612 }
613 status = is_valid_name(name_ucs2, False, False);
614 SAFE_FREE(name_ucs2);
615 return NT_STATUS_IS_OK(status);
616}
617
618/*****************************************************************************
619 * Convert a filename to DOS format. Return True if successful.
620 * Input: in Incoming name.
621 *
622 * out 8.3 DOS name.
623 *
624 * cache83 - If False, the mangled name cache will not be updated.
625 * This is usually used to prevent that we overwrite
626 * a conflicting cache entry prematurely, i.e. before
627 * we know whether the client is really interested in the
628 * current name. (See PR#13758). UKD.
629 *
630 * ****************************************************************************
631 */
632
633static bool hash_name_to_8_3(const char *in,
634 char out[13],
635 bool cache83,
636 int default_case,
637 const struct share_params *p)
638{
639 smb_ucs2_t *in_ucs2 = NULL;
640 magic_char = lp_magicchar(p);
641
642 DEBUG(5,("hash_name_to_8_3( %s, cache83 = %s)\n", in,
643 cache83 ? "True" : "False"));
644
645 if (push_ucs2_allocate(&in_ucs2, in) == (size_t)-1) {
646 DEBUG(0, ("push_ucs2_allocate failed!\n"));
647 return False;
648 }
649
650 /* If it's already 8.3, just copy. */
651 if (NT_STATUS_IS_OK(is_valid_name(in_ucs2, False, False)) &&
652 NT_STATUS_IS_OK(is_8_3_w(in_ucs2, False))) {
653 SAFE_FREE(in_ucs2);
654 safe_strcpy(out, in, 12);
655 return True;
656 }
657
658 SAFE_FREE(in_ucs2);
659 if (!to_8_3(in, out, default_case)) {
660 return False;
661 }
662
663 cache_mangled_name(out, in);
664
665 DEBUG(5,("hash_name_to_8_3(%s) ==> [%s]\n", in, out));
666 return True;
667}
668
669/*
670 the following provides the abstraction layer to make it easier
671 to drop in an alternative mangling implementation
672*/
673static struct mangle_fns mangle_fns = {
674 mangle_reset,
675 is_mangled,
676 must_mangle,
677 is_8_3,
678 lookup_name_from_8_3,
679 hash_name_to_8_3
680};
681
682/* return the methods for this mangling implementation */
683struct mangle_fns *mangle_hash_init(void)
684{
685 mangle_reset();
686
687 /* Create the in-memory tdb using our custom hash function. */
688 tdb_mangled_cache = tdb_open_ex("mangled_cache", 1031, TDB_INTERNAL,
689 (O_RDWR|O_CREAT), 0644, NULL, fast_string_hash);
690
691 return &mangle_fns;
692}
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