Initial import
[samba] / source / lib / util_sid.c
1 /* 
2    Unix SMB/CIFS implementation.
3    Samba utility functions
4    Copyright (C) Andrew Tridgell                1992-1998
5    Copyright (C) Luke Kenneth Caseson Leighton  1998-1999
6    Copyright (C) Jeremy Allison                 1999
7    Copyright (C) Stefan (metze) Metzmacher      2002
8    Copyright (C) Simo Sorce                     2002
9    Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2005
10       
11    This program is free software; you can redistribute it and/or modify
12    it under the terms of the GNU General Public License as published by
13    the Free Software Foundation; either version 2 of the License, or
14    (at your option) any later version.
15    
16    This program is distributed in the hope that it will be useful,
17    but WITHOUT ANY WARRANTY; without even the implied warranty of
18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19    GNU General Public License for more details.
20    
21    You should have received a copy of the GNU General Public License
22    along with this program; if not, write to the Free Software
23    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 */
25
26 #include "includes.h"
27
28 /*
29  * Some useful sids
30  */
31
32
33 const DOM_SID global_sid_World_Domain =               /* Everyone domain */
34 { 1, 0, {0,0,0,0,0,1}, {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
35 const DOM_SID global_sid_World =                      /* Everyone */
36 { 1, 1, {0,0,0,0,0,1}, {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
37 const DOM_SID global_sid_Creator_Owner_Domain =       /* Creator Owner domain */
38 { 1, 0, {0,0,0,0,0,3}, {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
39 const DOM_SID global_sid_NT_Authority =                 /* NT Authority */
40 { 1, 0, {0,0,0,0,0,5}, {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
41 const DOM_SID global_sid_System =                       /* System */
42 { 1, 1, {0,0,0,0,0,5}, {18,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
43 const DOM_SID global_sid_NULL =                         /* NULL sid */
44 { 1, 1, {0,0,0,0,0,0}, {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
45 const DOM_SID global_sid_Authenticated_Users =  /* All authenticated rids */
46 { 1, 1, {0,0,0,0,0,5}, {11,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
47 const DOM_SID global_sid_Network =                      /* Network rids */
48 { 1, 1, {0,0,0,0,0,5}, {2,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
49
50 const DOM_SID global_sid_Creator_Owner =                /* Creator Owner */
51 { 1, 1, {0,0,0,0,0,3}, {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
52 const DOM_SID global_sid_Creator_Group =                /* Creator Group */
53 { 1, 1, {0,0,0,0,0,3}, {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
54 const DOM_SID global_sid_Anonymous =                    /* Anonymous login */
55 { 1, 1, {0,0,0,0,0,5}, {7,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
56
57 const DOM_SID global_sid_Builtin =                      /* Local well-known domain */
58 { 1, 1, {0,0,0,0,0,5}, {32,0,0,0,0,0,0,0,0,0,0,0,0,0,0}};
59 const DOM_SID global_sid_Builtin_Administrators =       /* Builtin administrators */
60 { 1, 2, {0,0,0,0,0,5}, {32,544,0,0,0,0,0,0,0,0,0,0,0,0,0}};
61 const DOM_SID global_sid_Builtin_Users =                /* Builtin users */
62 { 1, 2, {0,0,0,0,0,5}, {32,545,0,0,0,0,0,0,0,0,0,0,0,0,0}};
63 const DOM_SID global_sid_Builtin_Guests =               /* Builtin guest users */
64 { 1, 2, {0,0,0,0,0,5}, {32,546,0,0,0,0,0,0,0,0,0,0,0,0,0}};
65 const DOM_SID global_sid_Builtin_Power_Users =  /* Builtin power users */
66 { 1, 2, {0,0,0,0,0,5}, {32,547,0,0,0,0,0,0,0,0,0,0,0,0,0}};
67 const DOM_SID global_sid_Builtin_Account_Operators =    /* Builtin account operators */
68 { 1, 2, {0,0,0,0,0,5}, {32,548,0,0,0,0,0,0,0,0,0,0,0,0,0}};
69 const DOM_SID global_sid_Builtin_Server_Operators =     /* Builtin server operators */
70 { 1, 2, {0,0,0,0,0,5}, {32,549,0,0,0,0,0,0,0,0,0,0,0,0,0}};
71 const DOM_SID global_sid_Builtin_Print_Operators =      /* Builtin print operators */
72 { 1, 2, {0,0,0,0,0,5}, {32,550,0,0,0,0,0,0,0,0,0,0,0,0,0}};
73 const DOM_SID global_sid_Builtin_Backup_Operators =     /* Builtin backup operators */
74 { 1, 2, {0,0,0,0,0,5}, {32,551,0,0,0,0,0,0,0,0,0,0,0,0,0}};
75 const DOM_SID global_sid_Builtin_Replicator =           /* Builtin replicator */
76 { 1, 2, {0,0,0,0,0,5}, {32,552,0,0,0,0,0,0,0,0,0,0,0,0,0}};
77
78 #define SECURITY_NULL_SID_AUTHORITY    0
79 #define SECURITY_WORLD_SID_AUTHORITY   1
80 #define SECURITY_LOCAL_SID_AUTHORITY   2
81 #define SECURITY_CREATOR_SID_AUTHORITY 3
82 #define SECURITY_NT_AUTHORITY          5
83
84 /*
85  * An NT compatible anonymous token.
86  */
87
88 static DOM_SID anon_sid_array[3] =
89 { { 1, 1, {0,0,0,0,0,1}, {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}},
90   { 1, 1, {0,0,0,0,0,5}, {2,0,0,0,0,0,0,0,0,0,0,0,0,0,0}},
91   { 1, 1, {0,0,0,0,0,5}, {7,0,0,0,0,0,0,0,0,0,0,0,0,0,0}} };
92 NT_USER_TOKEN anonymous_token = { 3, anon_sid_array, SE_NONE };
93
94 static DOM_SID system_sid_array[1] =
95 { { 1, 1, {0,0,0,0,0,5}, {18,0,0,0,0,0,0,0,0,0,0,0,0,0,0}} };
96 NT_USER_TOKEN system_token = { 1, system_sid_array, SE_ALL_PRIVS };
97
98 /****************************************************************************
99  Lookup string names for SID types.
100 ****************************************************************************/
101
102 static const struct {
103         enum SID_NAME_USE sid_type;
104         const char *string;
105 } sid_name_type[] = {
106         {SID_NAME_USER, "User"},
107         {SID_NAME_DOM_GRP, "Domain Group"},
108         {SID_NAME_DOMAIN, "Domain"},
109         {SID_NAME_ALIAS, "Local Group"},
110         {SID_NAME_WKN_GRP, "Well-known Group"},
111         {SID_NAME_DELETED, "Deleted Account"},
112         {SID_NAME_INVALID, "Invalid Account"},
113         {SID_NAME_UNKNOWN, "UNKNOWN"},
114         {SID_NAME_COMPUTER, "Computer"},
115
116         {(enum SID_NAME_USE)0, NULL}
117 };
118
119 const char *sid_type_lookup(uint32 sid_type) 
120 {
121         int i = 0;
122
123         /* Look through list */
124         while(sid_name_type[i].sid_type != 0) {
125                 if (sid_name_type[i].sid_type == sid_type)
126                         return sid_name_type[i].string;
127                 i++;
128         }
129
130         /* Default return */
131         return "SID *TYPE* is INVALID";
132 }
133
134 /**************************************************************************
135  Create the SYSTEM token.
136 ***************************************************************************/
137
138 NT_USER_TOKEN *get_system_token(void) 
139 {
140         return &system_token;
141 }
142
143 /******************************************************************
144  get the default domain/netbios name to be used when dealing 
145  with our passdb list of accounts
146 ******************************************************************/
147
148 const char *get_global_sam_name(void) 
149 {
150         if ((lp_server_role() == ROLE_DOMAIN_PDC) || (lp_server_role() == ROLE_DOMAIN_BDC)) {
151                 return lp_workgroup();
152         }
153         return global_myname();
154 }
155
156 /**************************************************************************
157  Splits a name of format \DOMAIN\name or name into its two components.
158  Sets the DOMAIN name to global_myname() if it has not been specified.
159 ***************************************************************************/
160
161 void split_domain_name(const char *fullname, char *domain, char *name)
162 {
163         pstring full_name;
164         const char *sep;
165         char *p;
166
167         sep = lp_winbind_separator();
168
169         *domain = *name = '\0';
170
171         if (fullname[0] == sep[0] || fullname[0] == '\\')
172                 fullname++;
173
174         pstrcpy(full_name, fullname);
175         p = strchr_m(full_name+1, '\\');
176         if (!p) p = strchr_m(full_name+1, sep[0]);
177
178         if (p != NULL) {
179                 *p = 0;
180                 fstrcpy(domain, full_name);
181                 fstrcpy(name, p+1);
182         } else {
183                 fstrcpy(domain, get_global_sam_name());
184                 fstrcpy(name, full_name);
185         }
186
187         DEBUG(10,("split_domain_name:name '%s' split into domain :'%s' and user :'%s'\n",
188                         fullname, domain, name));
189 }
190
191 /****************************************************************************
192  Test if a SID is wellknown and resolvable.
193 ****************************************************************************/
194
195 BOOL resolvable_wellknown_sid(DOM_SID *sid)
196 {
197         uint32 ia = (sid->id_auth[5]) +
198                         (sid->id_auth[4] << 8 ) +
199                         (sid->id_auth[3] << 16) +
200                         (sid->id_auth[2] << 24);
201
202         if (sid->sid_rev_num != SEC_DESC_REVISION || sid->num_auths < 1)
203                 return False;
204
205         return (ia == SECURITY_WORLD_SID_AUTHORITY ||
206                 ia == SECURITY_CREATOR_SID_AUTHORITY);
207 }
208
209 /*****************************************************************
210  Convert a SID to an ascii string.
211 *****************************************************************/
212
213 char *sid_to_string(fstring sidstr_out, const DOM_SID *sid)
214 {
215         char subauth[16];
216         int i;
217         uint32 ia;
218   
219         if (!sid) {
220                 fstrcpy(sidstr_out, "(NULL SID)");
221                 return sidstr_out;
222         }
223
224         /*
225          * BIG NOTE: this function only does SIDS where the identauth is not >= 2^32 
226          * in a range of 2^48.
227          */
228         ia = (sid->id_auth[5]) +
229                 (sid->id_auth[4] << 8 ) +
230                 (sid->id_auth[3] << 16) +
231                 (sid->id_auth[2] << 24);
232
233         slprintf(sidstr_out, sizeof(fstring) - 1, "S-%u-%lu", (unsigned int)sid->sid_rev_num, (unsigned long)ia);
234
235         for (i = 0; i < sid->num_auths; i++) {
236                 slprintf(subauth, sizeof(subauth)-1, "-%lu", (unsigned long)sid->sub_auths[i]);
237                 fstrcat(sidstr_out, subauth);
238         }
239
240         return sidstr_out;
241 }
242
243 /*****************************************************************
244  Useful function for debug lines.
245 *****************************************************************/  
246
247 const char *sid_string_static(const DOM_SID *sid)
248 {
249         static fstring sid_str;
250         sid_to_string(sid_str, sid);
251         return sid_str;
252 }
253
254 /*****************************************************************
255  Convert a string to a SID. Returns True on success, False on fail.
256 *****************************************************************/  
257    
258 BOOL string_to_sid(DOM_SID *sidout, const char *sidstr)
259 {
260         const char *p;
261         char *q;
262         /* BIG NOTE: this function only does SIDS where the identauth is not >= 2^32 */
263         uint32 conv;
264   
265         if ((sidstr[0] != 'S' && sidstr[0] != 's') || sidstr[1] != '-') {
266                 DEBUG(3,("string_to_sid: Sid %s does not start with 'S-'.\n", sidstr));
267                 return False;
268         }
269
270         ZERO_STRUCTP(sidout);
271
272         /* Get the revision number. */
273         p = sidstr + 2;
274         conv = (uint32) strtoul(p, &q, 10);
275         if (!q || (*q != '-')) {
276                 DEBUG(3,("string_to_sid: Sid %s is not in a valid format.\n", sidstr));
277                 return False;
278         }
279         sidout->sid_rev_num = (uint8) conv;
280         q++;
281
282         /* get identauth */
283         conv = (uint32) strtoul(q, &q, 10);
284         if (!q || (*q != '-')) {
285                 DEBUG(0,("string_to_sid: Sid %s is not in a valid format.\n", sidstr));
286                 return False;
287         }
288         /* identauth in decimal should be <  2^32 */
289         /* NOTE - the conv value is in big-endian format. */
290         sidout->id_auth[0] = 0;
291         sidout->id_auth[1] = 0;
292         sidout->id_auth[2] = (conv & 0xff000000) >> 24;
293         sidout->id_auth[3] = (conv & 0x00ff0000) >> 16;
294         sidout->id_auth[4] = (conv & 0x0000ff00) >> 8;
295         sidout->id_auth[5] = (conv & 0x000000ff);
296
297         q++;
298         sidout->num_auths = 0;
299
300         for(conv = (uint32) strtoul(q, &q, 10);
301             q && (*q =='-' || *q =='\0') && (sidout->num_auths < MAXSUBAUTHS);
302             conv = (uint32) strtoul(q, &q, 10)) {
303                 sid_append_rid(sidout, conv);
304                 if (*q == '\0')
305                         break;
306                 q++;
307         }
308                 
309         return True;
310 }
311
312 DOM_SID *string_sid_talloc(TALLOC_CTX *mem_ctx, const char *sidstr)
313 {
314         DOM_SID *result = TALLOC_P(mem_ctx, DOM_SID);
315
316         if (result == NULL)
317                 return NULL;
318
319         if (!string_to_sid(result, sidstr))
320                 return NULL;
321
322         return result;
323 }
324
325 /*****************************************************************
326  Add a rid to the end of a sid
327 *****************************************************************/  
328
329 BOOL sid_append_rid(DOM_SID *sid, uint32 rid)
330 {
331         if (sid->num_auths < MAXSUBAUTHS) {
332                 sid->sub_auths[sid->num_auths++] = rid;
333                 return True;
334         }
335         return False;
336 }
337
338 BOOL sid_compose(DOM_SID *dst, const DOM_SID *domain_sid, uint32 rid)
339 {
340         sid_copy(dst, domain_sid);
341         return sid_append_rid(dst, rid);
342 }
343
344 /*****************************************************************
345  Removes the last rid from the end of a sid
346 *****************************************************************/  
347
348 BOOL sid_split_rid(DOM_SID *sid, uint32 *rid)
349 {
350         if (sid->num_auths > 0) {
351                 sid->num_auths--;
352                 *rid = sid->sub_auths[sid->num_auths];
353                 return True;
354         }
355         return False;
356 }
357
358 /*****************************************************************
359  Return the last rid from the end of a sid
360 *****************************************************************/  
361
362 BOOL sid_peek_rid(const DOM_SID *sid, uint32 *rid)
363 {
364         if (!sid || !rid)
365                 return False;           
366         
367         if (sid->num_auths > 0) {
368                 *rid = sid->sub_auths[sid->num_auths - 1];
369                 return True;
370         }
371         return False;
372 }
373
374 /*****************************************************************
375  Return the last rid from the end of a sid
376  and check the sid against the exp_dom_sid  
377 *****************************************************************/  
378
379 BOOL sid_peek_check_rid(const DOM_SID *exp_dom_sid, const DOM_SID *sid, uint32 *rid)
380 {
381         if (!exp_dom_sid || !sid || !rid)
382                 return False;
383                         
384         if (sid->num_auths != (exp_dom_sid->num_auths+1)) {
385                 return False;
386         }
387
388         if (sid_compare_domain(exp_dom_sid, sid)!=0){
389                 *rid=(-1);
390                 return False;
391         }
392         
393         return sid_peek_rid(sid, rid);
394 }
395
396 /*****************************************************************
397  Copies a sid
398 *****************************************************************/  
399
400 void sid_copy(DOM_SID *dst, const DOM_SID *src)
401 {
402         int i;
403
404         ZERO_STRUCTP(dst);
405
406         dst->sid_rev_num = src->sid_rev_num;
407         dst->num_auths = src->num_auths;
408
409         memcpy(&dst->id_auth[0], &src->id_auth[0], sizeof(src->id_auth));
410
411         for (i = 0; i < src->num_auths; i++)
412                 dst->sub_auths[i] = src->sub_auths[i];
413 }
414
415 /*****************************************************************
416  Write a sid out into on-the-wire format.
417 *****************************************************************/  
418
419 BOOL sid_linearize(char *outbuf, size_t len, const DOM_SID *sid)
420 {
421         size_t i;
422
423         if (len < sid_size(sid))
424                 return False;
425
426         SCVAL(outbuf,0,sid->sid_rev_num);
427         SCVAL(outbuf,1,sid->num_auths);
428         memcpy(&outbuf[2], sid->id_auth, 6);
429         for(i = 0; i < sid->num_auths; i++)
430                 SIVAL(outbuf, 8 + (i*4), sid->sub_auths[i]);
431
432         return True;
433 }
434
435 /*****************************************************************
436  Parse a on-the-wire SID to a DOM_SID.
437 *****************************************************************/  
438
439 BOOL sid_parse(const char *inbuf, size_t len, DOM_SID *sid)
440 {
441         int i;
442         if (len < 8)
443                 return False;
444
445         ZERO_STRUCTP(sid);
446
447         sid->sid_rev_num = CVAL(inbuf, 0);
448         sid->num_auths = CVAL(inbuf, 1);
449         memcpy(sid->id_auth, inbuf+2, 6);
450         if (len < 8 + sid->num_auths*4)
451                 return False;
452         for (i=0;i<sid->num_auths;i++)
453                 sid->sub_auths[i] = IVAL(inbuf, 8+i*4);
454         return True;
455 }
456
457 /*****************************************************************
458  Compare the auth portion of two sids.
459 *****************************************************************/  
460
461 static int sid_compare_auth(const DOM_SID *sid1, const DOM_SID *sid2)
462 {
463         int i;
464
465         if (sid1 == sid2)
466                 return 0;
467         if (!sid1)
468                 return -1;
469         if (!sid2)
470                 return 1;
471
472         if (sid1->sid_rev_num != sid2->sid_rev_num)
473                 return sid1->sid_rev_num - sid2->sid_rev_num;
474
475         for (i = 0; i < 6; i++)
476                 if (sid1->id_auth[i] != sid2->id_auth[i])
477                         return sid1->id_auth[i] - sid2->id_auth[i];
478
479         return 0;
480 }
481
482 /*****************************************************************
483  Compare two sids.
484 *****************************************************************/  
485
486 int sid_compare(const DOM_SID *sid1, const DOM_SID *sid2)
487 {
488         int i;
489
490         if (sid1 == sid2)
491                 return 0;
492         if (!sid1)
493                 return -1;
494         if (!sid2)
495                 return 1;
496
497         /* Compare most likely different rids, first: i.e start at end */
498         if (sid1->num_auths != sid2->num_auths)
499                 return sid1->num_auths - sid2->num_auths;
500
501         for (i = sid1->num_auths-1; i >= 0; --i)
502                 if (sid1->sub_auths[i] != sid2->sub_auths[i])
503                         return sid1->sub_auths[i] - sid2->sub_auths[i];
504
505         return sid_compare_auth(sid1, sid2);
506 }
507
508 /*****************************************************************
509  See if 2 SIDs are in the same domain
510  this just compares the leading sub-auths
511 *****************************************************************/  
512
513 int sid_compare_domain(const DOM_SID *sid1, const DOM_SID *sid2)
514 {
515         int n, i;
516
517         n = MIN(sid1->num_auths, sid2->num_auths);
518
519         for (i = n-1; i >= 0; --i)
520                 if (sid1->sub_auths[i] != sid2->sub_auths[i])
521                         return sid1->sub_auths[i] - sid2->sub_auths[i];
522
523         return sid_compare_auth(sid1, sid2);
524 }
525
526 /*****************************************************************
527  Compare two sids.
528 *****************************************************************/  
529
530 BOOL sid_equal(const DOM_SID *sid1, const DOM_SID *sid2)
531 {
532         return sid_compare(sid1, sid2) == 0;
533 }
534
535 /*****************************************************************
536  Check if the SID is the builtin SID (S-1-5-32).
537 *****************************************************************/  
538
539 BOOL sid_check_is_builtin(const DOM_SID *sid)
540 {
541         return sid_equal(sid, &global_sid_Builtin);
542 }
543
544 /*****************************************************************
545  Check if the SID is one of the builtin SIDs (S-1-5-32-a).
546 *****************************************************************/  
547
548 BOOL sid_check_is_in_builtin(const DOM_SID *sid)
549 {
550         DOM_SID dom_sid;
551         uint32 rid;
552
553         sid_copy(&dom_sid, sid);
554         sid_split_rid(&dom_sid, &rid);
555         
556         return sid_equal(&dom_sid, &global_sid_Builtin);
557 }
558
559 /*****************************************************************
560  Calculates size of a sid.
561 *****************************************************************/  
562
563 size_t sid_size(const DOM_SID *sid)
564 {
565         if (sid == NULL)
566                 return 0;
567
568         return sid->num_auths * sizeof(uint32) + 8;
569 }
570
571 /*****************************************************************
572  Returns true if SID is internal (and non-mappable).
573 *****************************************************************/
574
575 BOOL non_mappable_sid(DOM_SID *sid)
576 {
577         DOM_SID dom;
578         uint32 rid;
579
580         sid_copy(&dom, sid);
581         sid_split_rid(&dom, &rid);
582
583         if (sid_equal(&dom, &global_sid_Builtin))
584                 return True;
585
586         if (sid_equal(&dom, &global_sid_NT_Authority))
587                 return True;
588
589         return False;
590 }
591
592 /*****************************************************************
593  Return the binary string representation of a DOM_SID.
594  Caller must free.
595 *****************************************************************/
596
597 char *sid_binstring(const DOM_SID *sid)
598 {
599         char *buf, *s;
600         int len = sid_size(sid);
601         buf = SMB_MALLOC(len);
602         if (!buf)
603                 return NULL;
604         sid_linearize(buf, len, sid);
605         s = binary_string(buf, len);
606         free(buf);
607         return s;
608 }
609
610 /*******************************************************************
611  Tallocs a duplicate SID. 
612 ********************************************************************/ 
613
614 DOM_SID *sid_dup_talloc(TALLOC_CTX *ctx, const DOM_SID *src)
615 {
616         DOM_SID *dst;
617         
618         if(!src)
619                 return NULL;
620         
621         if((dst = TALLOC_ZERO_P(ctx, DOM_SID)) != NULL) {
622                 sid_copy( dst, src);
623         }
624         
625         return dst;
626 }
627
628 /********************************************************************
629  Add SID to an array SIDs
630 ********************************************************************/
631
632 void add_sid_to_array(TALLOC_CTX *mem_ctx, const DOM_SID *sid, 
633                       DOM_SID **sids, size_t *num)
634 {
635         if (mem_ctx != NULL)
636                 *sids = TALLOC_REALLOC_ARRAY(mem_ctx, *sids, DOM_SID,
637                                              (*num)+1);
638         else
639                 *sids = SMB_REALLOC_ARRAY(*sids, DOM_SID, (*num)+1);
640
641         if (*sids == NULL)
642                 return;
643
644         sid_copy(&((*sids)[*num]), sid);
645         *num += 1;
646
647         return;
648 }
649
650
651 /********************************************************************
652  Add SID to an array SIDs ensuring that it is not already there
653 ********************************************************************/
654
655 void add_sid_to_array_unique(TALLOC_CTX *mem_ctx, const DOM_SID *sid,
656                              DOM_SID **sids, size_t *num_sids)
657 {
658         size_t i;
659
660         for (i=0; i<(*num_sids); i++) {
661                 if (sid_compare(sid, &(*sids)[i]) == 0)
662                         return;
663         }
664
665         add_sid_to_array(mem_ctx, sid, sids, num_sids);
666 }
667
668 /********************************************************************
669  Remove SID from an array
670 ********************************************************************/
671
672 void del_sid_from_array(const DOM_SID *sid, DOM_SID **sids, size_t *num)
673 {
674         DOM_SID *sid_list = *sids;
675         size_t i;
676
677         for ( i=0; i<*num; i++ ) {
678
679                 /* if we find the SID, then decrement the count
680                    and break out of the loop */
681
682                 if ( sid_equal(sid, &sid_list[i]) ) {
683                         *num -= 1;
684                         break;
685                 }
686         }
687
688         /* This loop will copy the remainder of the array 
689            if i < num of sids ni the array */
690
691         for ( ; i<*num; i++ ) 
692                 sid_copy( &sid_list[i], &sid_list[i+1] );
693         
694         return;
695 }
696
697 BOOL is_null_sid(const DOM_SID *sid)
698 {
699         static const DOM_SID null_sid = {0};
700         return sid_equal(sid, &null_sid);
701 }