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goma / wine / 210bd2dd94eb96b591ccd7e587797af103c227ff / . / server / token.c
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/*
* Tokens
*
* Copyright (C) 1998 Alexandre Julliard
* Copyright (C) 2003 Mike McCormack
* Copyright (C) 2005 Robert Shearman
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "config.h"
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include "windef.h"
#include "handle.h"
#include "thread.h"
#include "process.h"
#include "request.h"
#include "security.h"
#include "wine/unicode.h"
#define MAX_SUBAUTH_COUNT 1
const LUID SeIncreaseQuotaPrivilege = { 5, 0 };
const LUID SeSecurityPrivilege = { 8, 0 };
const LUID SeTakeOwnershipPrivilege = { 9, 0 };
const LUID SeLoadDriverPrivilege = { 10, 0 };
const LUID SeSystemProfilePrivilege = { 11, 0 };
const LUID SeSystemtimePrivilege = { 12, 0 };
const LUID SeProfileSingleProcessPrivilege = { 13, 0 };
const LUID SeIncreaseBasePriorityPrivilege = { 14, 0 };
const LUID SeCreatePagefilePrivilege = { 15, 0 };
const LUID SeBackupPrivilege = { 17, 0 };
const LUID SeRestorePrivilege = { 18, 0 };
const LUID SeShutdownPrivilege = { 19, 0 };
const LUID SeDebugPrivilege = { 20, 0 };
const LUID SeSystemEnvironmentPrivilege = { 22, 0 };
const LUID SeChangeNotifyPrivilege = { 23, 0 };
const LUID SeRemoteShutdownPrivilege = { 24, 0 };
const LUID SeUndockPrivilege = { 25, 0 };
const LUID SeManageVolumePrivilege = { 28, 0 };
const LUID SeImpersonatePrivilege = { 29, 0 };
const LUID SeCreateGlobalPrivilege = { 30, 0 };
static const SID world_sid = { SID_REVISION, 1, { SECURITY_WORLD_SID_AUTHORITY }, { SECURITY_WORLD_RID } };
static const SID local_sid = { SID_REVISION, 1, { SECURITY_LOCAL_SID_AUTHORITY }, { SECURITY_LOCAL_RID } };
static const SID interactive_sid = { SID_REVISION, 1, { SECURITY_NT_AUTHORITY }, { SECURITY_INTERACTIVE_RID } };
static const SID authenticated_user_sid = { SID_REVISION, 1, { SECURITY_NT_AUTHORITY }, { SECURITY_AUTHENTICATED_USER_RID } };
static const SID local_system_sid = { SID_REVISION, 1, { SECURITY_NT_AUTHORITY }, { SECURITY_LOCAL_SYSTEM_RID } };
static const PSID security_world_sid = (PSID)&world_sid;
static const PSID security_local_sid = (PSID)&local_sid;
const PSID security_interactive_sid = (PSID)&interactive_sid;
static const PSID security_authenticated_user_sid = (PSID)&authenticated_user_sid;
static const PSID security_local_system_sid = (PSID)&local_system_sid;
struct token
{
struct object obj; /* object header */
struct list privileges; /* privileges available to the token */
struct list groups; /* groups that the user of this token belongs to (sid_and_attributes) */
SID *user; /* SID of user this token represents */
unsigned primary; /* is this a primary or impersonation token? */
ACL *default_dacl; /* the default DACL to assign to objects created by this user */
};
struct privilege
{
struct list entry;
LUID luid;
unsigned enabled : 1; /* is the privilege currently enabled? */
unsigned def : 1; /* is the privilege enabled by default? */
};
struct sid_and_attributes
{
struct list entry;
unsigned enabled : 1; /* is the sid currently enabled? */
unsigned def : 1; /* is the sid enabled by default? */
unsigned logon : 1; /* is this a logon sid? */
unsigned mandatory: 1; /* is this sid always enabled? */
unsigned owner : 1; /* can this sid be an owner of an object? */
unsigned resource : 1; /* is this a domain-local group? */
unsigned deny_only: 1; /* is this a sid that should be use for denying only? */
SID sid;
};
static void token_dump( struct object *obj, int verbose );
static void token_destroy( struct object *obj );
static const struct object_ops token_ops =
{
sizeof(struct token), /* size */
token_dump, /* dump */
no_add_queue, /* add_queue */
NULL, /* remove_queue */
NULL, /* signaled */
NULL, /* satisfied */
no_signal, /* signal */
no_get_fd, /* get_fd */
no_close_handle, /* close_handle */
token_destroy /* destroy */
};
static void token_dump( struct object *obj, int verbose )
{
fprintf( stderr, "Security token\n" );
/* FIXME: dump token members */
}
static SID *security_sid_alloc( const SID_IDENTIFIER_AUTHORITY *idauthority, int subauthcount, const unsigned int subauth[] )
{
int i;
SID *sid = mem_alloc( FIELD_OFFSET(SID, SubAuthority[subauthcount]) );
if (!sid) return NULL;
sid->Revision = SID_REVISION;
sid->SubAuthorityCount = subauthcount;
sid->IdentifierAuthority = *idauthority;
for (i = 0; i < subauthcount; i++)
sid->SubAuthority[i] = subauth[i];
return sid;
}
static inline int security_equal_sid( const SID *sid1, const SID *sid2 )
{
return ((sid1->SubAuthorityCount == sid2->SubAuthorityCount) &&
!memcmp( sid1, sid2, FIELD_OFFSET(SID, SubAuthority[sid1->SubAuthorityCount]) ));
}
void security_set_thread_token( struct thread *thread, obj_handle_t handle )
{
if (!handle)
{
if (thread->token)
release_object( thread->token );
thread->token = NULL;
}
else
{
struct token *token = (struct token *)get_handle_obj( current->process,
handle,
TOKEN_IMPERSONATE,
&token_ops );
if (token)
{
if (thread->token)
release_object( thread->token );
thread->token = token;
}
}
}
static const ACE_HEADER *ace_next( const ACE_HEADER *ace )
{
return (const ACE_HEADER *)((const char *)ace + ace->AceSize);
}
static int acl_is_valid( const ACL *acl, size_t size )
{
ULONG i;
const ACE_HEADER *ace;
if (size < sizeof(ACL))
return FALSE;
size = min(size, MAX_ACL_LEN);
size -= sizeof(ACL);
ace = (const ACE_HEADER *)(acl + 1);
for (i = 0; i < acl->AceCount; i++)
{
const SID *sid;
size_t sid_size;
if (size < sizeof(ACE_HEADER))
return FALSE;
if (size < ace->AceSize)
return FALSE;
size -= ace->AceSize;
switch (ace->AceType)
{
case ACCESS_DENIED_ACE_TYPE:
sid = (const SID *)&((const ACCESS_DENIED_ACE *)ace)->SidStart;
sid_size = ace->AceSize - FIELD_OFFSET(ACCESS_DENIED_ACE, SidStart);
break;
case ACCESS_ALLOWED_ACE_TYPE:
sid = (const SID *)&((const ACCESS_ALLOWED_ACE *)ace)->SidStart;
sid_size = ace->AceSize - FIELD_OFFSET(ACCESS_ALLOWED_ACE, SidStart);
break;
case SYSTEM_AUDIT_ACE_TYPE:
sid = (const SID *)&((const SYSTEM_AUDIT_ACE *)ace)->SidStart;
sid_size = ace->AceSize - FIELD_OFFSET(SYSTEM_AUDIT_ACE, SidStart);
break;
case SYSTEM_ALARM_ACE_TYPE:
sid = (const SID *)&((const SYSTEM_ALARM_ACE *)ace)->SidStart;
sid_size = ace->AceSize - FIELD_OFFSET(SYSTEM_ALARM_ACE, SidStart);
break;
default:
return FALSE;
}
if (sid_size < FIELD_OFFSET(SID, SubAuthority[0]) ||
sid_size < FIELD_OFFSET(SID, SubAuthority[sid->SubAuthorityCount]))
return FALSE;
ace = ace_next( ace );
}
return TRUE;
}
/* gets the discretionary access control list from a security descriptor */
static inline const ACL *sd_get_dacl( const struct security_descriptor *sd, int *present )
{
*present = (sd->control & SE_DACL_PRESENT ? TRUE : FALSE);
if (sd->dacl_len)
return (const ACL *)((const char *)(sd + 1) +
sd->owner_len + sd->group_len + sd->sacl_len);
else
return NULL;
}
/* gets the system access control list from a security descriptor */
static inline const ACL *sd_get_sacl( const struct security_descriptor *sd, int *present )
{
*present = (sd->control & SE_SACL_PRESENT ? TRUE : FALSE);
if (sd->sacl_len)
return (const ACL *)((const char *)(sd + 1) +
sd->owner_len + sd->group_len);
else
return NULL;
}
/* gets the owner from a security descriptor */
static inline const SID *sd_get_owner( const struct security_descriptor *sd )
{
if (sd->owner_len)
return (const SID *)(sd + 1);
else
return NULL;
}
/* gets the primary group from a security descriptor */
static inline const SID *sd_get_group( const struct security_descriptor *sd )
{
if (sd->group_len)
return (const SID *)((const char *)(sd + 1) + sd->owner_len);
else
return NULL;
}
/* checks whether all members of a security descriptor fit inside the size
* of memory specified */
static int sd_is_valid( const struct security_descriptor *sd, size_t size )
{
size_t offset = sizeof(struct security_descriptor);
const SID *group;
const SID *owner;
const ACL *sacl;
const ACL *dacl;
int dummy;
if (size < offset)
return FALSE;
if ((sd->owner_len >= FIELD_OFFSET(SID, SubAuthority[255])) ||
(offset + sd->owner_len > size))
return FALSE;
owner = sd_get_owner( sd );
if (owner)
{
size_t needed_size = FIELD_OFFSET(SID, SubAuthority[owner->SubAuthorityCount]);
if ((sd->owner_len < sizeof(SID)) || (needed_size > sd->owner_len))
return FALSE;
}
offset += sd->owner_len;
if ((sd->group_len >= FIELD_OFFSET(SID, SubAuthority[255])) ||
(offset + sd->group_len > size))
return FALSE;
group = sd_get_group( sd );
if (group)
{
size_t needed_size = FIELD_OFFSET(SID, SubAuthority[group->SubAuthorityCount]);
if ((sd->owner_len < sizeof(SID)) || (needed_size > sd->owner_len))
return FALSE;
}
offset += sd->group_len;
if ((sd->sacl_len >= MAX_ACL_LEN) || (offset + sd->sacl_len > size))
return FALSE;
sacl = sd_get_sacl( sd, &dummy );
if (sacl && !acl_is_valid( sacl, sd->sacl_len ))
return FALSE;
offset += sd->sacl_len;
if ((sd->dacl_len >= MAX_ACL_LEN) || (offset + sd->dacl_len > size))
return FALSE;
dacl = sd_get_dacl( sd, &dummy );
if (dacl && !acl_is_valid( dacl, sd->dacl_len ))
return FALSE;
offset += sd->dacl_len;
return TRUE;
}
/* maps from generic rights to specific rights as given by a mapping */
static inline void map_generic_mask(unsigned int *mask, const GENERIC_MAPPING *mapping)
{
if (*mask & GENERIC_READ) *mask |= mapping->GenericRead;
if (*mask & GENERIC_WRITE) *mask |= mapping->GenericWrite;
if (*mask & GENERIC_EXECUTE) *mask |= mapping->GenericExecute;
if (*mask & GENERIC_ALL) *mask |= mapping->GenericAll;
*mask &= 0x0FFFFFFF;
}
static inline int is_equal_luid( const LUID *luid1, const LUID *luid2 )
{
return (luid1->LowPart == luid2->LowPart && luid1->HighPart == luid2->HighPart);
}
static inline void luid_and_attr_from_privilege( LUID_AND_ATTRIBUTES *out, const struct privilege *in)
{
out->Luid = in->luid;
out->Attributes =
(in->enabled ? SE_PRIVILEGE_ENABLED : 0) |
(in->def ? SE_PRIVILEGE_ENABLED_BY_DEFAULT : 0);
}
static struct privilege *privilege_add( struct token *token, const LUID *luid, int enabled )
{
struct privilege *privilege = mem_alloc( sizeof(*privilege) );
if (privilege)
{
privilege->luid = *luid;
privilege->def = privilege->enabled = (enabled != 0);
list_add_tail( &token->privileges, &privilege->entry );
}
return privilege;
}
static inline void privilege_remove( struct privilege *privilege )
{
list_remove( &privilege->entry );
free( privilege );
}
static void token_destroy( struct object *obj )
{
struct token* token;
struct list *cursor, *cursor_next;
assert( obj->ops == &token_ops );
token = (struct token *)obj;
free( token->user );
LIST_FOR_EACH_SAFE( cursor, cursor_next, &token->privileges )
{
struct privilege *privilege = LIST_ENTRY( cursor, struct privilege, entry );
privilege_remove( privilege );
}
LIST_FOR_EACH_SAFE( cursor, cursor_next, &token->groups )
{
struct sid_and_attributes *group = LIST_ENTRY( cursor, struct sid_and_attributes, entry );
list_remove( &group->entry );
free( group );
}
free( token->default_dacl );
}
/* creates a new token.
* groups may be NULL if group_count is 0.
* privs may be NULL if priv_count is 0.
* default_dacl may be NULL, indicating that all objects created by the user
* are unsecured.
*/
static struct token *create_token( unsigned primary, const SID *user,
const SID_AND_ATTRIBUTES *groups, unsigned int group_count,
const LUID_AND_ATTRIBUTES *privs, unsigned int priv_count,
const ACL *default_dacl )
{
struct token *token = alloc_object( &token_ops );
if (token)
{
int i;
list_init( &token->privileges );
list_init( &token->groups );
token->primary = primary;
/* copy user */
token->user = memdup( user, FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) );
if (!token->user)
{
release_object( token );
return NULL;
}
/* copy groups */
for (i = 0; i < group_count; i++)
{
size_t size = FIELD_OFFSET( struct sid_and_attributes, sid.SubAuthority[((const SID *)groups[i].Sid)->SubAuthorityCount] );
struct sid_and_attributes *group = mem_alloc( size );
memcpy( &group->sid, groups[i].Sid, FIELD_OFFSET( SID, SubAuthority[((const SID *)groups[i].Sid)->SubAuthorityCount] ) );
group->enabled = TRUE;
group->def = TRUE;
group->logon = FALSE;
group->mandatory = (groups[i].Attributes & SE_GROUP_MANDATORY) ? TRUE : FALSE;
group->owner = FALSE;
group->resource = FALSE;
group->deny_only = FALSE;
list_add_tail( &token->groups, &group->entry );
}
/* copy privileges */
for (i = 0; i < priv_count; i++)
{
/* note: we don't check uniqueness: the caller must make sure
* privs doesn't contain any duplicate luids */
if (!privilege_add( token, &privs[i].Luid,
privs[i].Attributes & SE_PRIVILEGE_ENABLED ))
{
release_object( token );
return NULL;
}
}
if (default_dacl)
{
token->default_dacl = memdup( default_dacl, default_dacl->AclSize );
if (!token->default_dacl)
{
release_object( token );
return NULL;
}
}
else
token->default_dacl = NULL;
}
return token;
}
static ACL *create_default_dacl( const SID *user )
{
ACCESS_ALLOWED_ACE *aaa;
ACL *default_dacl;
SID *sid;
size_t default_dacl_size = sizeof(ACL) +
2*(sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD)) +
sizeof(local_system_sid) +
FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
default_dacl = mem_alloc( default_dacl_size );
if (!default_dacl) return NULL;
default_dacl->AclRevision = MAX_ACL_REVISION;
default_dacl->Sbz1 = 0;
default_dacl->AclSize = default_dacl_size;
default_dacl->AceCount = 2;
default_dacl->Sbz2 = 0;
/* GENERIC_ALL for Local System */
aaa = (ACCESS_ALLOWED_ACE *)(default_dacl + 1);
aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
aaa->Header.AceFlags = 0;
aaa->Header.AceSize = (sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD)) +
sizeof(local_system_sid);
aaa->Mask = GENERIC_ALL;
sid = (SID *)&aaa->SidStart;
memcpy( sid, &local_system_sid, sizeof(local_system_sid) );
/* GENERIC_ALL for specified user */
aaa = (ACCESS_ALLOWED_ACE *)((const char *)aaa + aaa->Header.AceSize);
aaa->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
aaa->Header.AceFlags = 0;
aaa->Header.AceSize = (sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD)) +
FIELD_OFFSET( SID, SubAuthority[user->SubAuthorityCount] );
aaa->Mask = GENERIC_ALL;
sid = (SID *)&aaa->SidStart;
memcpy( sid, user, FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]) );
return default_dacl;
}
struct sid_data
{
SID_IDENTIFIER_AUTHORITY idauth;
int count;
unsigned int subauth[MAX_SUBAUTH_COUNT];
};
struct token *token_create_admin( void )
{
struct token *token = NULL;
static const SID_IDENTIFIER_AUTHORITY nt_authority = { SECURITY_NT_AUTHORITY };
static const unsigned int alias_admins_subauth[] = { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_ADMINS };
static const unsigned int alias_users_subauth[] = { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_USERS };
PSID alias_admins_sid;
PSID alias_users_sid;
ACL *default_dacl = create_default_dacl( &local_system_sid );
alias_admins_sid = security_sid_alloc( &nt_authority, sizeof(alias_admins_subauth)/sizeof(alias_admins_subauth[0]),
alias_admins_subauth );
alias_users_sid = security_sid_alloc( &nt_authority, sizeof(alias_users_subauth)/sizeof(alias_users_subauth[0]),
alias_users_subauth );
if (alias_admins_sid && alias_users_sid && default_dacl)
{
const LUID_AND_ATTRIBUTES admin_privs[] =
{
{ SeChangeNotifyPrivilege , SE_PRIVILEGE_ENABLED },
{ SeSecurityPrivilege , 0 },
{ SeBackupPrivilege , 0 },
{ SeRestorePrivilege , 0 },
{ SeSystemtimePrivilege , 0 },
{ SeShutdownPrivilege , 0 },
{ SeRemoteShutdownPrivilege , 0 },
{ SeTakeOwnershipPrivilege , 0 },
{ SeDebugPrivilege , 0 },
{ SeSystemEnvironmentPrivilege , 0 },
{ SeSystemProfilePrivilege , 0 },
{ SeProfileSingleProcessPrivilege, 0 },
{ SeIncreaseBasePriorityPrivilege, 0 },
{ SeLoadDriverPrivilege , 0 },
{ SeCreatePagefilePrivilege , 0 },
{ SeIncreaseQuotaPrivilege , 0 },
{ SeUndockPrivilege , 0 },
{ SeManageVolumePrivilege , 0 },
{ SeImpersonatePrivilege , SE_PRIVILEGE_ENABLED },
{ SeCreateGlobalPrivilege , SE_PRIVILEGE_ENABLED },
};
/* note: we don't include non-builtin groups here for the user -
* telling us these is the job of a client-side program */
const SID_AND_ATTRIBUTES admin_groups[] =
{
{ security_world_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
{ security_local_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
{ security_interactive_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
{ security_authenticated_user_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
{ alias_admins_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
{ alias_users_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
};
/* note: we just set the user sid to be the interactive builtin sid -
* we should really translate the UNIX user id to a sid */
token = create_token( TRUE, &interactive_sid,
admin_groups, sizeof(admin_groups)/sizeof(admin_groups[0]),
admin_privs, sizeof(admin_privs)/sizeof(admin_privs[0]),
default_dacl );
}
if (alias_admins_sid)
free( alias_admins_sid );
if (alias_users_sid)
free( alias_users_sid );
if (default_dacl)
free( default_dacl );
return token;
}
static struct privilege *token_find_privilege( struct token *token, const LUID *luid, int enabled_only )
{
struct privilege *privilege;
LIST_FOR_EACH_ENTRY( privilege, &token->privileges, struct privilege, entry )
{
if (is_equal_luid( luid, &privilege->luid ))
{
if (enabled_only && !privilege->enabled)
return NULL;
return privilege;
}
}
return NULL;
}
static unsigned int token_adjust_privileges( struct token *token, const LUID_AND_ATTRIBUTES *privs,
unsigned int count, LUID_AND_ATTRIBUTES *mod_privs,
unsigned int mod_privs_count )
{
int i;
unsigned int modified_count = 0;
for (i = 0; i < count; i++)
{
struct privilege *privilege =
token_find_privilege( token, &privs[i].Luid, FALSE );
if (!privilege)
{
set_error( STATUS_NOT_ALL_ASSIGNED );
continue;
}
if (privs[i].Attributes & SE_PRIVILEGE_REMOVE)
privilege_remove( privilege );
else
{
/* save previous state for caller */
if (mod_privs_count)
{
luid_and_attr_from_privilege(mod_privs, privilege);
mod_privs++;
mod_privs_count--;
modified_count++;
}
if (privs[i].Attributes & SE_PRIVILEGE_ENABLED)
privilege->enabled = TRUE;
else
privilege->enabled = FALSE;
}
}
return modified_count;
}
static void token_disable_privileges( struct token *token )
{
struct privilege *privilege;
LIST_FOR_EACH_ENTRY( privilege, &token->privileges, struct privilege, entry )
privilege->enabled = FALSE;
}
int token_check_privileges( struct token *token, int all_required,
const LUID_AND_ATTRIBUTES *reqprivs,
unsigned int count, LUID_AND_ATTRIBUTES *usedprivs)
{
int i;
unsigned int enabled_count = 0;
for (i = 0; i < count; i++)
{
struct privilege *privilege =
token_find_privilege( token, &reqprivs[i].Luid, TRUE );
if (usedprivs)
usedprivs[i] = reqprivs[i];
if (privilege && privilege->enabled)
{
enabled_count++;
if (usedprivs)
usedprivs[i].Attributes |= SE_PRIVILEGE_USED_FOR_ACCESS;
}
}
if (all_required)
return (enabled_count == count);
else
return (enabled_count > 0);
}
static int token_sid_present( struct token *token, const SID *sid, int deny )
{
struct sid_and_attributes *group;
if (security_equal_sid( token->user, sid )) return TRUE;
LIST_FOR_EACH_ENTRY( group, &token->groups, struct sid_and_attributes, entry )
{
if (!group->enabled) continue;
if (group->deny_only && !deny) continue;
if (security_equal_sid( &group->sid, sid )) return TRUE;
}
return FALSE;
}
/* checks access to a security descriptor. sd must have been validated by caller.
* it returns STATUS_SUCCESS if access was granted to the object, or an error
* status code if not, giving the reason. errors not relating to giving access
* to the object are returned in the status parameter. granted_access and
* status always have a valid value stored in them on return. */
static unsigned int token_access_check( struct token *token,
const struct security_descriptor *sd,
unsigned int desired_access,
LUID_AND_ATTRIBUTES *privs,
unsigned int *priv_count,
const GENERIC_MAPPING *mapping,
unsigned int *granted_access,
unsigned int *status )
{
unsigned int current_access = 0;
unsigned int denied_access = 0;
ULONG i;
const ACL *dacl;
int dacl_present;
const ACE_HEADER *ace;
const SID *owner;
/* assume success, but no access rights */
*status = STATUS_SUCCESS;
*granted_access = 0;
/* fail if desired_access contains generic rights */
if (desired_access & (GENERIC_READ|GENERIC_WRITE|GENERIC_EXECUTE|GENERIC_ALL))
{
*priv_count = 0;
*status = STATUS_GENERIC_NOT_MAPPED;
return STATUS_ACCESS_DENIED;
}
dacl = sd_get_dacl( sd, &dacl_present );
owner = sd_get_owner( sd );
if (!owner || !sd_get_group( sd ))
{
*priv_count = 0;
*status = STATUS_INVALID_SECURITY_DESCR;
return STATUS_ACCESS_DENIED;
}
/* 1: Grant desired access if the object is unprotected */
if (!dacl_present)
{
*priv_count = 0;
*granted_access = desired_access;
return STATUS_SUCCESS;
}
if (!dacl)
{
*priv_count = 0;
return STATUS_ACCESS_DENIED;
}
/* 2: Check if caller wants access to system security part. Note: access
* is only granted if specifically asked for */
if (desired_access & ACCESS_SYSTEM_SECURITY)
{
const LUID_AND_ATTRIBUTES security_priv = { SeSecurityPrivilege, 0 };
LUID_AND_ATTRIBUTES retpriv = security_priv;
if (token_check_privileges( token, TRUE, &security_priv, 1, &retpriv ))
{
if (priv_count)
{
/* assumes that there will only be one privilege to return */
if (*priv_count >= 1)
{
*priv_count = 1;
*privs = retpriv;
}
else
{
*priv_count = 1;
return STATUS_BUFFER_TOO_SMALL;
}
}
current_access |= ACCESS_SYSTEM_SECURITY;
if (desired_access == current_access)
{
*granted_access = current_access;
return STATUS_SUCCESS;
}
}
else
{
*priv_count = 0;
return STATUS_PRIVILEGE_NOT_HELD;
}
}
else if (priv_count) *priv_count = 0;
/* 3: Check whether the token is the owner */
/* NOTE: SeTakeOwnershipPrivilege is not checked for here - it is instead
* checked when a "set owner" call is made, overriding the access rights
* determined here. */
if (token_sid_present( token, owner, FALSE ))
{
current_access |= (READ_CONTROL | WRITE_DAC);
if (desired_access == current_access)
{
*granted_access = current_access;
return STATUS_SUCCESS;
}
}
/* 4: Grant rights according to the DACL */
ace = (const ACE_HEADER *)(dacl + 1);
for (i = 0; i < dacl->AceCount; i++)
{
const ACCESS_ALLOWED_ACE *aa_ace;
const ACCESS_DENIED_ACE *ad_ace;
const SID *sid;
switch (ace->AceType)
{
case ACCESS_DENIED_ACE_TYPE:
ad_ace = (const ACCESS_DENIED_ACE *)ace;
sid = (const SID *)&ad_ace->SidStart;
if (token_sid_present( token, sid, TRUE ))
{
unsigned int access = ad_ace->Mask;
map_generic_mask(&access, mapping);
if (desired_access & MAXIMUM_ALLOWED)
denied_access |= access;
else
{
denied_access |= (access & ~current_access);
if (desired_access & access)
{
*granted_access = 0;
return STATUS_SUCCESS;
}
}
}
break;
case ACCESS_ALLOWED_ACE_TYPE:
aa_ace = (const ACCESS_ALLOWED_ACE *)ace;
sid = (const SID *)&aa_ace->SidStart;
if (token_sid_present( token, sid, FALSE ))
{
unsigned int access = aa_ace->Mask;
map_generic_mask(&access, mapping);
if (desired_access & MAXIMUM_ALLOWED)
current_access |= access;
else
current_access |= (access & ~denied_access);
}
break;
}
/* don't bother carrying on checking if we've already got all of
* rights we need */
if (desired_access == *granted_access)
break;
ace = ace_next( ace );
}
if (desired_access & MAXIMUM_ALLOWED)
{
*granted_access = current_access & ~denied_access;
if (*granted_access)
return STATUS_SUCCESS;
else
return STATUS_ACCESS_DENIED;
}
else
{
if ((current_access & desired_access) == desired_access)
{
*granted_access = current_access & desired_access;
return STATUS_SUCCESS;
}
else
return STATUS_ACCESS_DENIED;
}
}
const ACL *token_get_default_dacl( struct token *token )
{
return token->default_dacl;
}
/* open a security token */
DECL_HANDLER(open_token)
{
if (req->flags & OPEN_TOKEN_THREAD)
{
struct thread *thread = get_thread_from_handle( req->handle, 0 );
if (thread)
{
if (thread->token)
reply->token = alloc_handle( current->process, thread->token, TOKEN_ALL_ACCESS, 0);
else
set_error(STATUS_NO_TOKEN);
release_object( thread );
}
}
else
{
struct process *process = get_process_from_handle( req->handle, 0 );
if (process)
{
if (process->token)
reply->token = alloc_handle( current->process, process->token, TOKEN_ALL_ACCESS, 0);
else
set_error(STATUS_NO_TOKEN);
release_object( process );
}
}
}
/* adjust the privileges held by a token */
DECL_HANDLER(adjust_token_privileges)
{
struct token *token;
unsigned int access = TOKEN_ADJUST_PRIVILEGES;
if (req->get_modified_state) access |= TOKEN_QUERY;
if ((token = (struct token *)get_handle_obj( current->process, req->handle,
access, &token_ops )))
{
const LUID_AND_ATTRIBUTES *privs = get_req_data();
LUID_AND_ATTRIBUTES *modified_privs = NULL;
unsigned int priv_count = get_req_data_size() / sizeof(LUID_AND_ATTRIBUTES);
unsigned int modified_priv_count = 0;
if (req->get_modified_state && !req->disable_all)
{
int i;
/* count modified privs */
for (i = 0; i < priv_count; i++)
{
struct privilege *privilege =
token_find_privilege( token, &privs[i].Luid, FALSE );
if (privilege && req->get_modified_state)
modified_priv_count++;
}
reply->len = modified_priv_count;
modified_priv_count = min( modified_priv_count, get_reply_max_size() / sizeof(*modified_privs) );
if (modified_priv_count)
modified_privs = set_reply_data_size( modified_priv_count * sizeof(*modified_privs) );
}
reply->len = modified_priv_count * sizeof(*modified_privs);
if (req->disable_all)
token_disable_privileges( token );
else
modified_priv_count = token_adjust_privileges( token, privs,
priv_count, modified_privs, modified_priv_count );
release_object( token );
}
}
/* retrieves the list of privileges that may be held be the token */
DECL_HANDLER(get_token_privileges)
{
struct token *token;
if ((token = (struct token *)get_handle_obj( current->process, req->handle,
TOKEN_QUERY,
&token_ops )))
{
int priv_count = 0;
LUID_AND_ATTRIBUTES *privs;
struct privilege *privilege;
LIST_FOR_EACH_ENTRY( privilege, &token->privileges, struct privilege, entry )
priv_count++;
reply->len = priv_count * sizeof(*privs);
if (reply->len <= get_reply_max_size())
{
privs = set_reply_data_size( priv_count * sizeof(*privs) );
if (privs)
{
int i = 0;
LIST_FOR_EACH_ENTRY( privilege, &token->privileges, struct privilege, entry )
{
luid_and_attr_from_privilege( &privs[i], privilege );
i++;
}
}
}
else
set_error(STATUS_BUFFER_TOO_SMALL);
release_object( token );
}
}
/* creates a duplicate of the token */
DECL_HANDLER(duplicate_token)
{
struct token *src_token;
if ((src_token = (struct token *)get_handle_obj( current->process, req->handle,
TOKEN_DUPLICATE,
&token_ops )))
{
/* FIXME: use req->impersonation_level */
struct token *token = create_token( req->primary, src_token->user, NULL, 0, NULL, 0, src_token->default_dacl );
if (token)
{
struct privilege *privilege;
struct sid_and_attributes *group;
unsigned int access;
/* copy groups */
LIST_FOR_EACH_ENTRY( group, &src_token->groups, struct sid_and_attributes, entry )
{
size_t size = FIELD_OFFSET( struct sid_and_attributes, sid.SubAuthority[group->sid.SubAuthorityCount] );
struct sid_and_attributes *newgroup = mem_alloc( size );
memcpy( newgroup, group, size );
list_add_tail( &token->groups, &newgroup->entry );
}
/* copy privileges */
LIST_FOR_EACH_ENTRY( privilege, &src_token->privileges, struct privilege, entry )
privilege_add( token, &privilege->luid, privilege->enabled );
access = req->access;
if (access & MAXIMUM_ALLOWED) access = TOKEN_ALL_ACCESS; /* FIXME: needs general solution */
reply->new_handle = alloc_handle( current->process, token, access, req->inherit);
release_object( token );
}
release_object( src_token );
}
}
/* checks the specified privileges are held by the token */
DECL_HANDLER(check_token_privileges)
{
struct token *token;
if ((token = (struct token *)get_handle_obj( current->process, req->handle,
TOKEN_QUERY,
&token_ops )))
{
unsigned int count = get_req_data_size() / sizeof(LUID_AND_ATTRIBUTES);
if (get_reply_max_size() >= count * sizeof(LUID_AND_ATTRIBUTES))
{
LUID_AND_ATTRIBUTES *usedprivs = set_reply_data_size( count * sizeof(*usedprivs) );
reply->has_privileges = token_check_privileges( token, req->all_required, get_req_data(), count, usedprivs );
}
else
set_error( STATUS_BUFFER_OVERFLOW );
release_object( token );
}
}
/* checks that a user represented by a token is allowed to access an object
* represented by a security descriptor */
DECL_HANDLER(access_check)
{
size_t sd_size = get_req_data_size();
const struct security_descriptor *sd = get_req_data();
struct token *token;
if (!sd_is_valid( sd, sd_size ))
{
set_error( STATUS_ACCESS_VIOLATION );
return;
}
if ((token = (struct token *)get_handle_obj( current->process, req->handle,
TOKEN_QUERY,
&token_ops )))
{
GENERIC_MAPPING mapping;
unsigned int status;
LUID_AND_ATTRIBUTES priv;
unsigned int priv_count = 1;
memset(&priv, 0, sizeof(priv));
/* only impersonation tokens may be used with this function */
if (token->primary)
{
set_error( STATUS_NO_IMPERSONATION_TOKEN );
release_object( token );
return;
}
mapping.GenericRead = req->mapping_read;
mapping.GenericWrite = req->mapping_write;
mapping.GenericExecute = req->mapping_execute;
mapping.GenericAll = req->mapping_all;
reply->access_status = token_access_check(
token, sd, req->desired_access, &priv, &priv_count, &mapping,
&reply->access_granted, &status );
reply->privileges_len = priv_count*sizeof(LUID_AND_ATTRIBUTES);
if ((priv_count > 0) && (reply->privileges_len <= get_reply_max_size()))
{
LUID_AND_ATTRIBUTES *privs = set_reply_data_size( priv_count * sizeof(*privs) );
memcpy( privs, &priv, sizeof(priv) );
}
if (status != STATUS_SUCCESS)
set_error( status );
release_object( token );
}
}
/* */
DECL_HANDLER(get_token_user)
{
struct token *token;
reply->user_len = 0;
if ((token = (struct token *)get_handle_obj( current->process, req->handle,
TOKEN_QUERY,
&token_ops )))
{
const SID *user = token->user;
reply->user_len = FIELD_OFFSET(SID, SubAuthority[user->SubAuthorityCount]);
if (reply->user_len <= get_reply_max_size())
{
SID *user_reply = set_reply_data_size( reply->user_len );
if (user_reply)
memcpy( user_reply, user, reply->user_len );
}
else set_error( STATUS_BUFFER_TOO_SMALL );
release_object( token );
}
}