make sid_binstring available without HAVE_ADS
[ira/wip.git] / source3 / lib / util_sid.c
index f2f7b3c8ae1c0453b12568b52a133d84f36bbf77..72365f5e46d866c04cbaddfbb6f91cbc3fd30083 100644 (file)
@@ -23,8 +23,6 @@
 
 #include "includes.h"
 
-
-extern int DEBUGLEVEL;
 DOM_SID global_sam_sid;
 extern pstring global_myname;
 extern fstring global_myworkgroup;
@@ -33,61 +31,162 @@ extern fstring global_myworkgroup;
  * Some useful sids
  */
 
-DOM_SID global_sid_S_1_5_0x20; /* local well-known domain */
-DOM_SID global_sid_World_Domain;    /* everyone */
-DOM_SID global_sid_World;    /* everyone */
-DOM_SID global_sid_Creator_Owner_Domain;    /* Creator Owner */
-DOM_SID global_sid_Creator_Owner;    /* Creator Owner */
-DOM_SID global_sid_NT_Authority;    /* NT Authority */
+DOM_SID global_sid_Builtin;                            /* Local well-known domain */
+DOM_SID global_sid_World_Domain;               /* Everyone domain */
+DOM_SID global_sid_World;                              /* Everyone */
+DOM_SID global_sid_Creator_Owner_Domain;    /* Creator Owner domain */
+DOM_SID global_sid_Creator_Owner;              /* Creator Owner */
+DOM_SID global_sid_NT_Authority;               /* NT Authority */
+DOM_SID global_sid_NULL;                       /* NULL sid */
+DOM_SID global_sid_Builtin_Guests;                     /* Builtin guest users */
+DOM_SID global_sid_Authenticated_Users;                /* All authenticated rids */
+DOM_SID global_sid_Network;                                    /* Network rids */
+DOM_SID global_sid_Anonymous;                          /* Anonymous login */
+
+const DOM_SID *global_sid_everyone = &global_sid_World;
 
 typedef struct _known_sid_users {
        uint32 rid;
-       uint8 sid_name_use;
+       enum SID_NAME_USE sid_name_use;
        char *known_user_name;
 } known_sid_users;
 
 /* static known_sid_users no_users[] = {{0, 0, NULL}}; */
-static known_sid_users everyone_users[] = {{ 0, SID_NAME_WKN_GRP, "Everyone" }, {0, 0, NULL}};
-static known_sid_users creator_owner_users[] = {{ 0, SID_NAME_ALIAS, "Creator Owner" }, {0, 0, NULL}};
-static known_sid_users nt_authority_users[] = {{ 1, SID_NAME_ALIAS, "Dialup" },
-                                                                                          { 2, SID_NAME_ALIAS, "Network"},
-                                                                                          { 3, SID_NAME_ALIAS, "Batch"},
-                                                                                          { 4, SID_NAME_ALIAS, "Interactive"},
-                                                                                          { 6, SID_NAME_ALIAS, "Service"},
-                                                                                          { 7, SID_NAME_ALIAS, "AnonymousLogon"},
-                                                                                          { 8, SID_NAME_ALIAS, "Proxy"},
-                                                                                          { 9, SID_NAME_ALIAS, "ServerLogon"},
-                                                                                          {0, 0, NULL}};
+
+static known_sid_users everyone_users[] = {
+       { 0, SID_NAME_WKN_GRP, "Everyone" },
+       {0, (enum SID_NAME_USE)0, NULL}};
+
+static known_sid_users creator_owner_users[] = {
+       { 0, SID_NAME_ALIAS, "Creator Owner" },
+       {0, (enum SID_NAME_USE)0, NULL}};
+
+static known_sid_users nt_authority_users[] = {
+       {  1, SID_NAME_ALIAS, "Dialup" },
+       {  2, SID_NAME_ALIAS, "Network"},
+       {  3, SID_NAME_ALIAS, "Batch"},
+       {  4, SID_NAME_ALIAS, "Interactive"},
+       {  6, SID_NAME_ALIAS, "Service"},
+       {  7, SID_NAME_ALIAS, "AnonymousLogon"},
+       {  8, SID_NAME_ALIAS, "Proxy"},
+       {  9, SID_NAME_ALIAS, "ServerLogon"},
+       { 11, SID_NAME_ALIAS, "Authenticated Users"},
+       { 18, SID_NAME_ALIAS, "SYSTEM"},
+       {  0, (enum SID_NAME_USE)0, NULL}};
+
+static known_sid_users builtin_groups[] = {
+       { BUILTIN_ALIAS_RID_ADMINS, SID_NAME_ALIAS, "Administrators" },
+       { BUILTIN_ALIAS_RID_USERS, SID_NAME_ALIAS, "Users" },
+       { BUILTIN_ALIAS_RID_GUESTS, SID_NAME_ALIAS, "Guests" },
+       { BUILTIN_ALIAS_RID_ACCOUNT_OPS, SID_NAME_ALIAS, "Account Operators" },
+       { BUILTIN_ALIAS_RID_SYSTEM_OPS, SID_NAME_ALIAS, "Server Operators" },
+       { BUILTIN_ALIAS_RID_PRINT_OPS, SID_NAME_ALIAS, "Print Operators" },
+       { BUILTIN_ALIAS_RID_BACKUP_OPS, SID_NAME_ALIAS, "Backup Operators" },
+       {  0, (enum SID_NAME_USE)0, NULL}};
+
+#define MAX_SID_NAMES  7
 
 static struct sid_name_map_info
 {
        DOM_SID *sid;
        char *name;
        known_sid_users *known_users;
-}
-sid_name_map[] =
-{
-       { &global_sam_sid, global_myname, NULL},
-       { &global_sam_sid, global_myworkgroup, NULL},
-       { &global_sid_S_1_5_0x20, "BUILTIN", NULL},
-       { &global_sid_World_Domain, "", &everyone_users[0] },
-       { &global_sid_Creator_Owner_Domain, "", &creator_owner_users[0] },
-       { &global_sid_NT_Authority, "NT Authority", &nt_authority_users[0] },
-       { NULL, NULL, NULL}
+} sid_name_map[MAX_SID_NAMES];
+
+static BOOL sid_name_map_initialized = False;
+
+/*
+ * An NT compatible anonymous token.
+ */
+
+static DOM_SID anon_sid_array[3];
+
+NT_USER_TOKEN anonymous_token = {
+    3,
+    anon_sid_array
 };
 
+/**************************************************************************
+ quick init function
+ *************************************************************************/
+static void init_sid_name_map (void)
+{
+       int i = 0;
+       
+       if (sid_name_map_initialized) return;
+       
+
+       if ((lp_security() == SEC_USER) && lp_domain_logons()) {
+               sid_name_map[i].sid = &global_sam_sid;
+               sid_name_map[i].name = global_myworkgroup;
+               sid_name_map[i].known_users = NULL;
+               i++;
+               sid_name_map[i].sid = &global_sam_sid;
+               sid_name_map[i].name = global_myname;
+               sid_name_map[i].known_users = NULL;
+               i++;
+       }
+       else {
+               sid_name_map[i].sid = &global_sam_sid;
+               sid_name_map[i].name = global_myname;
+               sid_name_map[i].known_users = NULL;
+               i++;
+       }
+
+       sid_name_map[i].sid = &global_sid_Builtin;
+       sid_name_map[i].name = "BUILTIN";
+       sid_name_map[i].known_users = &builtin_groups[0];
+       i++;
+       
+       sid_name_map[i].sid = &global_sid_World_Domain;
+       sid_name_map[i].name = "";
+       sid_name_map[i].known_users = &everyone_users[0];
+       i++;
+
+       sid_name_map[i].sid = &global_sid_Creator_Owner_Domain;
+       sid_name_map[i].name = "";
+       sid_name_map[i].known_users = &creator_owner_users[0];
+       i++;
+               
+       sid_name_map[i].sid = &global_sid_NT_Authority;
+       sid_name_map[i].name = "NT Authority";
+       sid_name_map[i].known_users = &nt_authority_users[0];
+       i++;
+               
+
+       /* end of array */
+       sid_name_map[i].sid = NULL;
+       sid_name_map[i].name = NULL;
+       sid_name_map[i].known_users = NULL;
+       
+       sid_name_map_initialized = True;
+               
+       return;
+
+}
+
 /****************************************************************************
  Creates some useful well known sids
 ****************************************************************************/
 
 void generate_wellknown_sids(void)
 {
-       string_to_sid(&global_sid_S_1_5_0x20, "S-1-5-32");
+       string_to_sid(&global_sid_Builtin, "S-1-5-32");
+       string_to_sid(&global_sid_Builtin_Guests, "S-1-5-32-546");
        string_to_sid(&global_sid_World_Domain, "S-1-1");
        string_to_sid(&global_sid_World, "S-1-1-0");
        string_to_sid(&global_sid_Creator_Owner_Domain, "S-1-3");
        string_to_sid(&global_sid_Creator_Owner, "S-1-3-0");
        string_to_sid(&global_sid_NT_Authority, "S-1-5");
+       string_to_sid(&global_sid_NULL, "S-1-0-0");
+       string_to_sid(&global_sid_Authenticated_Users, "S-1-5-11");
+       string_to_sid(&global_sid_Network, "S-1-5-2");
+       string_to_sid(&global_sid_Anonymous, "S-1-5-7");
+
+       /* Create the anon token. */
+       sid_copy( &anonymous_token.user_sids[0], &global_sid_World);
+       sid_copy( &anonymous_token.user_sids[1], &global_sid_Network);
+       sid_copy( &anonymous_token.user_sids[2], &global_sid_Anonymous);
 }
 
 /**************************************************************************
@@ -98,8 +197,12 @@ BOOL map_domain_sid_to_name(DOM_SID *sid, char *nt_domain)
 {
        fstring sid_str;
        int i = 0;
+       
        sid_to_string(sid_str, sid);
 
+       if (!sid_name_map_initialized) 
+               init_sid_name_map();
+
        DEBUG(5,("map_domain_sid_to_name: %s\n", sid_str));
 
        if (nt_domain == NULL)
@@ -108,7 +211,7 @@ BOOL map_domain_sid_to_name(DOM_SID *sid, char *nt_domain)
        while (sid_name_map[i].sid != NULL) {
                sid_to_string(sid_str, sid_name_map[i].sid);
                DEBUG(5,("map_domain_sid_to_name: compare: %s\n", sid_str));
-               if (sid_equal(sid_name_map[i].sid, sid)) {
+               if (sid_equal(sid_name_map[i].sid, sid)) {              
                        fstrcpy(nt_domain, sid_name_map[i].name);
                        DEBUG(5,("map_domain_sid_to_name: found '%s'\n", nt_domain));
                        return True;
@@ -125,11 +228,14 @@ BOOL map_domain_sid_to_name(DOM_SID *sid, char *nt_domain)
  Looks up a known username from one of the known domains.
 ***************************************************************************/
 
-BOOL lookup_known_rid(DOM_SID *sid, uint32 rid, char *name, uint8 *psid_name_use)
+BOOL lookup_known_rid(DOM_SID *sid, uint32 rid, char *name, enum SID_NAME_USE *psid_name_use)
 {
        int i = 0;
        struct sid_name_map_info *psnm;
 
+       if (!sid_name_map_initialized) 
+               init_sid_name_map();
+
        for(i = 0; sid_name_map[i].sid != NULL; i++) {
                psnm = &sid_name_map[i];
                if(sid_equal(psnm->sid, sid)) {
@@ -169,10 +275,13 @@ BOOL map_domain_name_to_sid(DOM_SID *sid, char *nt_domain)
                DEBUG(5,("map_domain_name_to_sid: overriding blank name to %s\n", nt_domain));
                sid_copy(sid, &global_sam_sid);
                return True;
-    }
+       }
 
        DEBUG(5,("map_domain_name_to_sid: %s\n", nt_domain));
 
+       if (!sid_name_map_initialized) 
+               init_sid_name_map();
+
        while (sid_name_map[i].name != NULL) {
                DEBUG(5,("map_domain_name_to_sid: compare: %s\n", sid_name_map[i].name));
                if (strequal(sid_name_map[i].name, nt_domain)) {
@@ -197,15 +306,18 @@ BOOL map_domain_name_to_sid(DOM_SID *sid, char *nt_domain)
 void split_domain_name(const char *fullname, char *domain, char *name)
 {
        pstring full_name;
-       char *p;
+       char *p, *sep;
+
+       sep = lp_winbind_separator();
 
        *domain = *name = '\0';
 
-       if (fullname[0] == '\\')
+       if (fullname[0] == sep[0] || fullname[0] == '\\')
                fullname++;
 
        pstrcpy(full_name, fullname);
-       p = strchr(full_name+1, '\\');
+       p = strchr_m(full_name+1, '\\');
+       if (!p) p = strchr_m(full_name+1, sep[0]);
 
        if (p != NULL) {
                *p = 0;
@@ -241,7 +353,6 @@ char *sid_to_string(fstring sidstr_out, DOM_SID *sid)
     fstrcat(sidstr_out, subauth);
   }
 
-  DEBUG(7,("sid_to_string returning %s\n", sidstr_out));
   return sidstr_out;
 }
 
@@ -299,8 +410,6 @@ BOOL string_to_sid(DOM_SID *sidout, char *sidstr)
        sid_append_rid(sidout, (uint32)strtoul(tok, NULL, 10));
   }
 
-  DEBUG(7,("string_to_sid: converted SID %s ok\n", sidstr));
-
   return True;
 }
 
@@ -331,6 +440,19 @@ BOOL sid_split_rid(DOM_SID *sid, uint32 *rid)
        return False;
 }
 
+/*****************************************************************
+ Return the last rid from the end of a sid
+*****************************************************************/  
+
+BOOL sid_peek_rid(DOM_SID *sid, uint32 *rid)
+{
+       if (sid->num_auths > 0) {
+               *rid = sid->sub_auths[sid->num_auths - 1];
+               return True;
+       }
+       return False;
+}
+
 /*****************************************************************
  Copies a sid
 *****************************************************************/  
@@ -339,6 +461,8 @@ void sid_copy(DOM_SID *dst, const DOM_SID *src)
 {
        int i;
 
+       memset((char *)dst, '\0', sizeof(DOM_SID));
+
        dst->sid_rev_num = src->sid_rev_num;
        dst->num_auths = src->num_auths;
 
@@ -370,12 +494,11 @@ DOM_SID *sid_dup(DOM_SID *src)
 /*****************************************************************
  Write a sid out into on-the-wire format.
 *****************************************************************/  
-
 BOOL sid_linearize(char *outbuf, size_t len, DOM_SID *sid)
 {
        size_t i;
 
-       if(len < sid_size(sid))
+       if (len < sid_size(sid))
                return False;
 
        SCVAL(outbuf,0,sid->sid_rev_num);
@@ -388,327 +511,172 @@ BOOL sid_linearize(char *outbuf, size_t len, DOM_SID *sid)
 }
 
 /*****************************************************************
- Compare two sids.
+ parse a on-the-wire SID to a DOM_SID
 *****************************************************************/  
+BOOL sid_parse(char *inbuf, size_t len, DOM_SID *sid)
+{
+       int i;
+       if (len < 8) return False;
+       sid->sid_rev_num = CVAL(inbuf, 0);
+       sid->num_auths = CVAL(inbuf, 1);
+       memcpy(sid->id_auth, inbuf+2, 6);
+       if (len < 8 + sid->num_auths*4) return False;
+       for (i=0;i<sid->num_auths;i++) {
+               sid->sub_auths[i] = IVAL(inbuf, 8+i*4);
+       }
+       return True;
+}
+
 
-BOOL sid_equal(DOM_SID *sid1, DOM_SID *sid2)
+/*****************************************************************
+ Compare the domain portion of two sids.
+*****************************************************************/  
+int sid_compare_domain(const DOM_SID *sid1, const DOM_SID *sid2)
 {
        int i;
 
-       /* compare most likely different rids, first: i.e start at end */
-       for (i = sid1->num_auths-1; i >= 0; --i)
-               if (sid1->sub_auths[i] != sid2->sub_auths[i])
-                       return False;
+       if (sid1 == sid2) return 0;
+       if (!sid1) return -1;
+       if (!sid2) return 1;
 
-       if (sid1->num_auths != sid2->num_auths)
-               return False;
        if (sid1->sid_rev_num != sid2->sid_rev_num)
-               return False;
+               return sid1->sid_rev_num - sid2->sid_rev_num;
 
        for (i = 0; i < 6; i++)
                if (sid1->id_auth[i] != sid2->id_auth[i])
-                       return False;
+                       return sid1->id_auth[i] - sid2->id_auth[i];
 
-       return True;
+       return 0;
 }
 
-
 /*****************************************************************
- Calculates size of a sid.
+ Compare two sids.
 *****************************************************************/  
-
-size_t sid_size(DOM_SID *sid)
+int sid_compare(const DOM_SID *sid1, const DOM_SID *sid2)
 {
-       if (sid == NULL)
-               return 0;
-
-       return sid->num_auths * sizeof(uint32) + 8;
-}
+       int i;
 
-static BOOL read_sid_from_file(int fd, char *sid_file, DOM_SID *sid)
-{   
-  fstring fline;
-       fstring sid_str;
-    
-  memset(fline, '\0', sizeof(fline));
+       if (sid1 == sid2) return 0;
+       if (!sid1) return -1;
+       if (!sid2) return 1;
 
-  if (read(fd, fline, sizeof(fline) -1 ) < 0) {
-    DEBUG(0,("unable to read file %s. Error was %s\n",
-           sid_file, strerror(errno) ));
-    return False;
-  }
+       /* compare most likely different rids, first: i.e start at end */
+       if (sid1->num_auths != sid2->num_auths)
+               return sid1->num_auths - sid2->num_auths;
 
-  /*
-   * Convert to the machine SID.
-   */
+       for (i = sid1->num_auths-1; i >= 0; --i)
+               if (sid1->sub_auths[i] != sid2->sub_auths[i])
+                       return sid1->sub_auths[i] - sid2->sub_auths[i];
 
-  fline[sizeof(fline)-1] = '\0';
-  if (!string_to_sid(sid, fline)) {
-    DEBUG(0,("unable to read sid.\n"));
-    return False;
-  }
+       return sid_compare_domain(sid1, sid2);
+}
 
-       sid_to_string(sid_str, sid);
-       DEBUG(5,("read_sid_from_file: sid %s\n", sid_str));
 
-  return True;
+/*****************************************************************
+ Compare two sids.
+*****************************************************************/  
+BOOL sid_equal(const DOM_SID *sid1, const DOM_SID *sid2)
+{
+       return sid_compare(sid1, sid2) == 0;
 }
 
-/****************************************************************************
- Generate the global machine sid. Look for the DOMAINNAME.SID file first, if
- not found then look in smb.conf and use it to create the DOMAINNAME.SID file.
-****************************************************************************/
-BOOL read_sid(char *sam_name, DOM_SID *sid)
-{
-       int fd;
-       char *p;
-       pstring sid_file;
-       fstring file_name;
-       SMB_STRUCT_STAT st;
 
-       pstrcpy(sid_file, lp_smb_passwd_file());
+/*****************************************************************
+ Check if the SID is our domain SID (S-1-5-21-x-y-z).
+*****************************************************************/  
+BOOL sid_check_is_domain(const DOM_SID *sid)
+{
+       return sid_equal(sid, &global_sam_sid);
+}
 
-       DEBUG(10,("read_sid: Domain: %s\n", sam_name));
 
-       if (sid_file[0] == 0)
-       {
-               DEBUG(0,("cannot find smb passwd file\n"));
-               return False;
-       }
+/*****************************************************************
+ Check if the SID is the builtin SID (S-1-5-32).
+*****************************************************************/  
+BOOL sid_check_is_builtin(const DOM_SID *sid)
+{
+       return sid_equal(sid, &global_sid_Builtin);
+}
 
-       p = strrchr(sid_file, '/');
-       if (p != NULL)
-       {
-               *++p = '\0';
-       }
 
-       if (!directory_exist(sid_file, NULL))
-       {
-               if (mkdir(sid_file, 0700) != 0)
-               {
-                       DEBUG(0,("can't create private directory %s : %s\n",
-                                sid_file, strerror(errno)));
-                       return False;
-               }
-       }
+/*****************************************************************
+ Check if the SID is our domain SID (S-1-5-21-x-y-z).
+*****************************************************************/  
+BOOL sid_check_is_in_our_domain(const DOM_SID *sid)
+{
+       DOM_SID dom_sid;
+       uint32 rid;
 
-       slprintf(file_name, sizeof(file_name)-1, "%s.SID", sam_name);
-       strupper(file_name);
-       pstrcat(sid_file, file_name);
-    
-       if ((fd = sys_open(sid_file, O_RDWR | O_CREAT, 0644)) == -1) {
-               DEBUG(0,("unable to open or create file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               return False;
-       } 
-  
-       /*
-        * Check if the file contains data.
-        */
+       sid_copy(&dom_sid, sid);
+       sid_split_rid(&dom_sid, &rid);
        
-       if (sys_fstat(fd, &st) < 0) {
-               DEBUG(0,("unable to stat file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               close(fd);
-               return False;
-       } 
-  
-       if (st.st_size == 0)
-       {
-               close(fd);
-               return False;
-       }
+       return sid_equal(&dom_sid, &global_sam_sid);
+}
 
-       /*
-        * We have a valid SID - read it.
-        */
+/*****************************************************************
+ Check if the SID is our domain SID (S-1-5-21-x-y-z).
+*****************************************************************/  
+BOOL sid_check_is_in_builtin(const DOM_SID *sid)
+{
+       DOM_SID dom_sid;
+       uint32 rid;
 
-       if (!read_sid_from_file(fd, sid_file, sid))
-       {
-               DEBUG(0,("unable to read file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               close(fd);
-               return False;
-       }
-       close(fd);
-       return True;
-}   
+       sid_copy(&dom_sid, sid);
+       sid_split_rid(&dom_sid, &rid);
+       
+       return sid_equal(&dom_sid, &global_sid_Builtin);
+}
 
 
-/****************************************************************************
- Generate the global machine sid. Look for the DOMAINNAME.SID file first, if
- not found then look in smb.conf and use it to create the DOMAINNAME.SID file.
-****************************************************************************/
-BOOL write_sid(char *sam_name, DOM_SID *sid)
-{
-       int fd;
-       char *p;
-       pstring sid_file;
-       fstring sid_string;
-       fstring file_name;
-       SMB_STRUCT_STAT st;
-
-       pstrcpy(sid_file, lp_smb_passwd_file());
-       sid_to_string(sid_string, sid);
-
-       DEBUG(10,("write_sid: Domain: %s SID: %s\n", sam_name, sid_string));
-       fstrcat(sid_string, "\n");
-
-       if (sid_file[0] == 0)
-       {
-               DEBUG(0,("cannot find smb passwd file\n"));
-               return False;
-       }
+/*****************************************************************
+ Calculates size of a sid.
+*****************************************************************/  
 
-       p = strrchr(sid_file, '/');
-       if (p != NULL)
-       {
-               *++p = '\0';
-       }
+size_t sid_size(DOM_SID *sid)
+{
+       if (sid == NULL)
+               return 0;
 
-       if (!directory_exist(sid_file, NULL)) {
-               if (mkdir(sid_file, 0700) != 0) {
-                       DEBUG(0,("can't create private directory %s : %s\n",
-                                sid_file, strerror(errno)));
-                       return False;
-               }
-       }
+       return sid->num_auths * sizeof(uint32) + 8;
+}
 
-       slprintf(file_name, sizeof(file_name)-1, "%s.SID", sam_name);
-       strupper(file_name);
-       pstrcat(sid_file, file_name);
-    
-       if ((fd = sys_open(sid_file, O_RDWR | O_CREAT, 0644)) == -1) {
-               DEBUG(0,("unable to open or create file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               return False;
-       } 
-  
-       /*
-        * Check if the file contains data.
-        */
-       
-       if (sys_fstat(fd, &st) < 0) {
-               DEBUG(0,("unable to stat file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               close(fd);
-               return False;
-       } 
-  
-       if (st.st_size > 0)
-       {
-               /*
-                * We have a valid SID already.
-                */
-               close(fd);
-               DEBUG(0,("SID file %s already exists\n", sid_file));
-               return False;
-       } 
-  
-       if (!do_file_lock(fd, 60, F_WRLCK))
-       {
-               DEBUG(0,("unable to lock file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               close(fd);
-               return False;
-       } 
-  
-       /*
-        * At this point we have a blocking lock on the SID
-        * file - check if in the meantime someone else wrote
-        * SID data into the file. If so - they were here first,
-        * use their data.
-        */
-       
-       if (sys_fstat(fd, &st) < 0)
-       {
-               DEBUG(0,("unable to stat file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               close(fd);
-               return False;
-       } 
-  
-       if (st.st_size > 0)
-       {
-               /*
-                * Unlock as soon as possible to reduce
-                * contention on the exclusive lock.
-                */ 
-               do_file_lock(fd, 60, F_UNLCK);
-               
-               /*
-                * We have a valid SID already.
-                */
-               
-               DEBUG(0,("SID file %s already exists\n", sid_file));
-               close(fd);
-               return False;
-       } 
-       
-       /*
-        * The file is still empty and we have an exlusive lock on it.
-        * Write out out SID data into the file.
-        */
-       
-       if (fchmod(fd, 0644) < 0)
-       {
-               DEBUG(0,("unable to set correct permissions on file %s. \
-Error was %s\n", sid_file, strerror(errno) ));
-               close(fd);
-               return False;
-       } 
-       
-       if (write(fd, sid_string, strlen(sid_string)) != strlen(sid_string))
-       {
-               DEBUG(0,("unable to write file %s. Error was %s\n",
-                        sid_file, strerror(errno) ));
-               close(fd);
-               return False;
-       } 
-       
-       /*
-        * Unlock & exit.
-        */
-       
-       do_file_lock(fd, 60, F_UNLCK);
-       close(fd);
-       return True;
-}   
+/*****************************************************************
+ Returns true if SID is internal (and non-mappable).
+*****************************************************************/
 
-/****************************************************************************
-create a random SID.
-****************************************************************************/
-BOOL create_new_sid(DOM_SID *sid)
+BOOL non_mappable_sid(DOM_SID *sid)
 {
-       uchar raw_sid_data[12];
-       fstring sid_string;
-       int i;
+       DOM_SID dom;
+       uint32 rid;
 
-       /*
-        * Generate the new sid data & turn it into a string.
-        */
-       generate_random_buffer(raw_sid_data, 12, True);
-               
-       fstrcpy(sid_string, "S-1-5-21");
-       for(i = 0; i < 3; i++)
-       {
-               fstring tmp_string;
-               slprintf(tmp_string, sizeof(tmp_string) - 1, "-%u", IVAL(raw_sid_data, i*4));
-               fstrcat(sid_string, tmp_string);
-       }
-       
-       fstrcat(sid_string, "\n");
-       
-       /*
-        * Ensure our new SID is valid.
-        */
-       
-       if (!string_to_sid(sid, sid_string))
-       {
-               DEBUG(0,("unable to generate machine SID.\n"));
-               return False;
-       } 
+       sid_copy(&dom, sid);
+       sid_split_rid(&dom, &rid);
 
-       return True;
+       if (sid_equal(&dom, &global_sid_Builtin))
+               return True;
+
+       if (sid_equal(&dom, &global_sid_Creator_Owner_Domain))
+               return True;
+       if (sid_equal(&dom, &global_sid_NT_Authority))
+               return True;
+
+       return False;
 }
-  
+
+/*
+  return the binary string representation of a DOM_SID
+  caller must free
+*/
+char *sid_binstring(DOM_SID *sid)
+{
+       char *buf, *s;
+       int len = sid_size(sid);
+       buf = malloc(len);
+       if (!buf) return NULL;
+       sid_linearize(buf, len, sid);
+       s = binary_string(buf, len);
+       free(buf);
+       return s;
+}
+