source: branches/samba-3.3.x/source/lib/privileges_basic.c

/*
   Unix SMB/CIFS implementation.
   Privileges handling functions
   Copyright (C) Jean François Micouleau       1998-2001
   Copyright (C) Simo Sorce                     2002-2003
   Copyright (C) Gerald (Jerry) Carter          2005
   Copyright (C) Michael Adam                   2007
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/*
 * Basic privileges functions (mask-operations and conversion 
 * functions between the different formats (se_priv, privset, luid)
 * moved here * from lib/privileges.c to minimize linker deps.
 *
 * generally SID- and LUID-related code is left in lib/privileges.c
 *
 * some extra functions to hide privs array from lib/privileges.c
 */
 
#include "includes.h"

const SE_PRIV se_priv_all         = SE_ALL_PRIVS;
static const SE_PRIV se_priv_end  = SE_END;

/* Define variables for all privileges so we can use the
   SE_PRIV* in the various se_priv_XXX() functions */

const SE_PRIV se_priv_none       = SE_NONE;
const SE_PRIV se_machine_account = SE_MACHINE_ACCOUNT;
const SE_PRIV se_print_operator  = SE_PRINT_OPERATOR;
const SE_PRIV se_add_users       = SE_ADD_USERS;
const SE_PRIV se_disk_operators  = SE_DISK_OPERATOR;
const SE_PRIV se_remote_shutdown = SE_REMOTE_SHUTDOWN;
const SE_PRIV se_restore         = SE_RESTORE;
const SE_PRIV se_take_ownership  = SE_TAKE_OWNERSHIP;

/********************************************************************
 This is a list of privileges reported by a WIndows 2000 SP4 AD DC
 just for reference purposes (and I know the LUID is not guaranteed 
 across reboots):

            SeCreateTokenPrivilege  Create a token object ( 0x0, 0x2 )
     SeAssignPrimaryTokenPrivilege  Replace a process level token ( 0x0, 0x3 )
             SeLockMemoryPrivilege  Lock pages in memory ( 0x0, 0x4 )
          SeIncreaseQuotaPrivilege  Increase quotas ( 0x0, 0x5 )
         SeMachineAccountPrivilege  Add workstations to domain ( 0x0, 0x6 )
                    SeTcbPrivilege  Act as part of the operating system ( 0x0, 0x7 )
               SeSecurityPrivilege  Manage auditing and security log ( 0x0, 0x8 )
          SeTakeOwnershipPrivilege  Take ownership of files or other objects ( 0x0, 0x9 )
             SeLoadDriverPrivilege  Load and unload device drivers ( 0x0, 0xa )
          SeSystemProfilePrivilege  Profile system performance ( 0x0, 0xb )
             SeSystemtimePrivilege  Change the system time ( 0x0, 0xc )
   SeProfileSingleProcessPrivilege  Profile single process ( 0x0, 0xd )
   SeIncreaseBasePriorityPrivilege  Increase scheduling priority ( 0x0, 0xe )
         SeCreatePagefilePrivilege  Create a pagefile ( 0x0, 0xf )
        SeCreatePermanentPrivilege  Create permanent shared objects ( 0x0, 0x10 )
                 SeBackupPrivilege  Back up files and directories ( 0x0, 0x11 )
                SeRestorePrivilege  Restore files and directories ( 0x0, 0x12 )
               SeShutdownPrivilege  Shut down the system ( 0x0, 0x13 )
                  SeDebugPrivilege  Debug programs ( 0x0, 0x14 )
                  SeAuditPrivilege  Generate security audits ( 0x0, 0x15 )
      SeSystemEnvironmentPrivilege  Modify firmware environment values ( 0x0, 0x16 )
           SeChangeNotifyPrivilege  Bypass traverse checking ( 0x0, 0x17 )
         SeRemoteShutdownPrivilege  Force shutdown from a remote system ( 0x0, 0x18 )
                 SeUndockPrivilege  Remove computer from docking station ( 0x0, 0x19 )
              SeSyncAgentPrivilege  Synchronize directory service data ( 0x0, 0x1a )
       SeEnableDelegationPrivilege  Enable computer and user accounts to be trusted for delegation ( 0x0, 0x1b )
           SeManageVolumePrivilege  Perform volume maintenance tasks ( 0x0, 0x1c )
            SeImpersonatePrivilege  Impersonate a client after authentication ( 0x0, 0x1d )
           SeCreateGlobalPrivilege  Create global objects ( 0x0, 0x1e )

 ********************************************************************/

/* we have to define the LUID here due to a horrible check by printmig.exe
   that requires the SeBackupPrivilege match what is in Windows.  So match
   those that we implement and start Samba privileges at 0x1001 */
   
PRIVS privs[] = {
#if 0   /* usrmgr will display these twice if you include them.  We don't 
           use them but we'll keep the bitmasks reserved in privileges.h anyways */
           
        {SE_NETWORK_LOGON,      "SeNetworkLogonRight",          "Access this computer from network",       { 0x0, 0x0 }},
        {SE_INTERACTIVE_LOGON,  "SeInteractiveLogonRight",      "Log on locally",                          { 0x0, 0x0 }},
        {SE_BATCH_LOGON,        "SeBatchLogonRight",            "Log on as a batch job",                   { 0x0, 0x0 }},
        {SE_SERVICE_LOGON,      "SeServiceLogonRight",          "Log on as a service",                     { 0x0, 0x0 }},
#endif
        {SE_MACHINE_ACCOUNT,    "SeMachineAccountPrivilege",    "Add machines to domain",                  { 0x0, 0x0006 }},
        {SE_TAKE_OWNERSHIP,     "SeTakeOwnershipPrivilege",     "Take ownership of files or other objects",{ 0x0, 0x0009 }},
        {SE_BACKUP,             "SeBackupPrivilege",            "Back up files and directories",           { 0x0, 0x0011 }},
        {SE_RESTORE,            "SeRestorePrivilege",           "Restore files and directories",           { 0x0, 0x0012 }},
        {SE_REMOTE_SHUTDOWN,    "SeRemoteShutdownPrivilege",    "Force shutdown from a remote system",     { 0x0, 0x0018 }},
        
        {SE_PRINT_OPERATOR,     "SePrintOperatorPrivilege",     "Manage printers",                         { 0x0, 0x1001 }},
        {SE_ADD_USERS,          "SeAddUsersPrivilege",          "Add users and groups to the domain",      { 0x0, 0x1002 }},
        {SE_DISK_OPERATOR,      "SeDiskOperatorPrivilege",      "Manage disk shares",                      { 0x0, 0x1003 }},

        {SE_END, "", "", { 0x0, 0x0 }}
};

/***************************************************************************
 copy an SE_PRIV structure
****************************************************************************/

bool se_priv_copy( SE_PRIV *dst, const SE_PRIV *src )
{
        if ( !dst || !src )
                return False;
                
        memcpy( dst, src, sizeof(SE_PRIV) );
        
        return True;
}

/***************************************************************************
 put all privileges into a mask
****************************************************************************/

bool se_priv_put_all_privileges(SE_PRIV *mask)
{
        int i;
        uint32 num_privs = count_all_privileges();

        if (!se_priv_copy(mask, &se_priv_none)) {
                return False;
        }
        for ( i=0; i<num_privs; i++ ) {
                se_priv_add(mask, &privs[i].se_priv); 
        }
        return True;
}

/***************************************************************************
 combine 2 SE_PRIV structures and store the resulting set in mew_mask
****************************************************************************/

void se_priv_add( SE_PRIV *mask, const SE_PRIV *addpriv )
{
        int i;

        for ( i=0; i<SE_PRIV_MASKSIZE; i++ ) {
                mask->mask[i] |= addpriv->mask[i];
        }
}

/***************************************************************************
 remove one SE_PRIV sytucture from another and store the resulting set 
 in mew_mask
****************************************************************************/

void se_priv_remove( SE_PRIV *mask, const SE_PRIV *removepriv )
{       
        int i;

        for ( i=0; i<SE_PRIV_MASKSIZE; i++ ) {
                mask->mask[i] &= ~removepriv->mask[i];
        }
}

/***************************************************************************
 invert a given SE_PRIV and store the set in new_mask
****************************************************************************/

static void se_priv_invert( SE_PRIV *new_mask, const SE_PRIV *mask )
{       
        SE_PRIV allprivs;
        
        se_priv_copy( &allprivs, &se_priv_all );
        se_priv_remove( &allprivs, mask );
        se_priv_copy( new_mask, &allprivs );
}

/***************************************************************************
 check if 2 SE_PRIV structure are equal
****************************************************************************/

bool se_priv_equal( const SE_PRIV *mask1, const SE_PRIV *mask2 )
{       
        return ( memcmp(mask1, mask2, sizeof(SE_PRIV)) == 0 );
}

/***************************************************************************
 check if a SE_PRIV has any assigned privileges
****************************************************************************/

static bool se_priv_empty( const SE_PRIV *mask )
{
        SE_PRIV p1;
        int i;
        
        se_priv_copy( &p1, mask );

        for ( i=0; i<SE_PRIV_MASKSIZE; i++ ) {
                p1.mask[i] &= se_priv_all.mask[i];
        }
        
        return se_priv_equal( &p1, &se_priv_none );
}

/*********************************************************************
 Lookup the SE_PRIV value for a privilege name 
*********************************************************************/

bool se_priv_from_name( const char *name, SE_PRIV *mask )
{
        int i;

        for ( i=0; !se_priv_equal(&privs[i].se_priv, &se_priv_end); i++ ) {
                if ( strequal( privs[i].name, name ) ) {
                        se_priv_copy( mask, &privs[i].se_priv );
                        return True;
                }
        }

        return False;
}

/***************************************************************************
 dump an SE_PRIV structure to the log files
****************************************************************************/

void dump_se_priv( int dbg_cl, int dbg_lvl, const SE_PRIV *mask )
{
        int i;
        
        DEBUGADDC( dbg_cl, dbg_lvl,("SE_PRIV "));
        
        for ( i=0; i<SE_PRIV_MASKSIZE; i++ ) {
                DEBUGADDC( dbg_cl, dbg_lvl,(" 0x%x", mask->mask[i] ));
        }
                
        DEBUGADDC( dbg_cl, dbg_lvl, ("\n"));
}

/****************************************************************************
 check if the privilege is in the privilege list
****************************************************************************/

bool is_privilege_assigned(const SE_PRIV *privileges,
                           const SE_PRIV *check)
{
        SE_PRIV p1, p2;

        if ( !privileges || !check )
                return False;
        
        /* everyone has privileges if you aren't checking for any */
        
        if ( se_priv_empty( check ) ) {
                DEBUG(1,("is_privilege_assigned: no privileges in check_mask!\n"));
                return True;
        }
        
        se_priv_copy( &p1, check );
        
        /* invert the SE_PRIV we want to check for and remove that from the 
           original set.  If we are left with the SE_PRIV we are checking 
           for then return True */
           
        se_priv_invert( &p1, check );
        se_priv_copy( &p2, privileges );
        se_priv_remove( &p2, &p1 );
        
        return se_priv_equal( &p2, check );
}

/****************************************************************************
 check if the privilege is in the privilege list
****************************************************************************/

static bool is_any_privilege_assigned( SE_PRIV *privileges, const SE_PRIV *check )
{
        SE_PRIV p1, p2;

        if ( !privileges || !check )
                return False;
        
        /* everyone has privileges if you aren't checking for any */
        
        if ( se_priv_empty( check ) ) {
                DEBUG(1,("is_any_privilege_assigned: no privileges in check_mask!\n"));
                return True;
        }
        
        se_priv_copy( &p1, check );
        
        /* invert the SE_PRIV we want to check for and remove that from the 
           original set.  If we are left with the SE_PRIV we are checking 
           for then return True */
           
        se_priv_invert( &p1, check );
        se_priv_copy( &p2, privileges );
        se_priv_remove( &p2, &p1 );
        
        /* see if we have any bits left */
        
        return !se_priv_empty( &p2 );
}

/*********************************************************************
 Generate the LUID_ATTR structure based on a bitmask
*********************************************************************/

const char* get_privilege_dispname( const char *name )
{
        int i;

        if (!name) {
                return NULL;
        }

        for ( i=0; !se_priv_equal(&privs[i].se_priv, &se_priv_end); i++ ) {
        
                if ( strequal( privs[i].name, name ) ) {
                        return privs[i].description;
                }
        }

        return NULL;
}

/****************************************************************************
 initialise a privilege list and set the talloc context 
 ****************************************************************************/
 
/****************************************************************************
 Does the user have the specified privilege ?  We only deal with one privilege
 at a time here.
*****************************************************************************/

bool user_has_privileges(const NT_USER_TOKEN *token, const SE_PRIV *privilege)
{
        if ( !token )
                return False;

        return is_privilege_assigned( &token->privileges, privilege );
}

/****************************************************************************
 Does the user have any of the specified privileges ?  We only deal with one privilege
 at a time here.
*****************************************************************************/

bool user_has_any_privilege(NT_USER_TOKEN *token, const SE_PRIV *privilege)
{
        if ( !token )
                return False;

        return is_any_privilege_assigned( &token->privileges, privilege );
}

/*******************************************************************
 return the number of elements in the privlege array
*******************************************************************/

int count_all_privileges( void )
{
        /*
         * The -1 is due to the weird SE_END record...
         */
        return (sizeof(privs) / sizeof(privs[0])) - 1;
}


/*********************************************************************
 Generate the LUID_ATTR structure based on a bitmask
 The assumption here is that the privilege has already been validated
 so we are guaranteed to find it in the list. 
*********************************************************************/

LUID_ATTR get_privilege_luid( SE_PRIV *mask )
{
        LUID_ATTR priv_luid;
        int i;

        ZERO_STRUCT( priv_luid );
        
        for ( i=0; !se_priv_equal(&privs[i].se_priv, &se_priv_end); i++ ) {
        
                if ( se_priv_equal( &privs[i].se_priv, mask ) ) {
                        priv_luid.luid = privs[i].luid;
                        break;
                }
        }

        return priv_luid;
}

/****************************************************************************
 Convert a LUID to a named string
****************************************************************************/

const char *luid_to_privilege_name(const LUID *set)
{
        int i;

        if (set->high != 0)
                return NULL;

        for ( i=0; !se_priv_equal(&privs[i].se_priv, &se_priv_end); i++ ) {
                if ( set->low == privs[i].luid.low ) {
                        return privs[i].name;
                }
        }
        
        return NULL;
}


/****************************************************************************
 add a privilege to a privilege array
 ****************************************************************************/

static bool privilege_set_add(PRIVILEGE_SET *priv_set, LUID_ATTR set)
{
        LUID_ATTR *new_set;

        /* we can allocate memory to add the new privilege */

        new_set = TALLOC_REALLOC_ARRAY(priv_set->mem_ctx, priv_set->set, LUID_ATTR, priv_set->count + 1);
        if ( !new_set ) {
                DEBUG(0,("privilege_set_add: failed to allocate memory!\n"));
                return False;
        }       

        new_set[priv_set->count].luid.high = set.luid.high;
        new_set[priv_set->count].luid.low = set.luid.low;
        new_set[priv_set->count].attr = set.attr;

        priv_set->count++;
        priv_set->set = new_set;

        return True;
}

/*******************************************************************
*******************************************************************/

bool se_priv_to_privilege_set( PRIVILEGE_SET *set, SE_PRIV *mask )
{
        int i;
        uint32 num_privs = count_all_privileges();
        LUID_ATTR luid;
        
        luid.attr = 0;
        luid.luid.high = 0;
        
        for ( i=0; i<num_privs; i++ ) {
                if ( !is_privilege_assigned(mask, &privs[i].se_priv) )
                        continue;
                
                luid.luid = privs[i].luid;
                
                if ( !privilege_set_add( set, luid ) )
                        return False;
        }

        return True;
}

/*******************************************************************
*******************************************************************/

static bool luid_to_se_priv( struct lsa_LUID *luid, SE_PRIV *mask )
{
        int i;
        uint32 num_privs = count_all_privileges();
        
        for ( i=0; i<num_privs; i++ ) {
                if ( luid->low == privs[i].luid.low ) {
                        se_priv_copy( mask, &privs[i].se_priv );
                        return True;
                }
        }

        return False;
}

/*******************************************************************
*******************************************************************/

bool privilege_set_to_se_priv( SE_PRIV *mask, struct lsa_PrivilegeSet *privset )
{
        int i;
        
        ZERO_STRUCTP( mask );
        
        for ( i=0; i<privset->count; i++ ) {
                SE_PRIV r;
        
                /* sanity check for invalid privilege.  we really
                   only care about the low 32 bits */
                   
                if ( privset->set[i].luid.high != 0 )
                        return False;
                
                if ( luid_to_se_priv( &privset->set[i].luid, &r ) )             
                        se_priv_add( mask, &r );
        }

        return True;
}