diff --git a/include/wine/server_protocol.h b/include/wine/server_protocol.h
index 00471154d9a..2f1d6f6f25e 100644
--- a/include/wine/server_protocol.h
+++ b/include/wine/server_protocol.h
@@ -385,6 +385,14 @@ struct acl
     unsigned short pad2;
 };
 
+struct sid
+{
+    unsigned char revision;
+    unsigned char sub_count;
+    unsigned char id_auth[6];
+    unsigned int  sub_auth[15];
+};
+
 typedef struct
 {
     unsigned int read;
@@ -4411,7 +4419,7 @@ struct filter_token_request
     unsigned int  flags;
     data_size_t   privileges_size;
     /* VARARG(privileges,luid_attr,privileges_size); */
-    /* VARARG(disable_sids,SID); */
+    /* VARARG(disable_sids,sid); */
 };
 struct filter_token_reply
 {
@@ -4450,7 +4458,7 @@ struct get_token_sid_reply
 {
     struct reply_header __header;
     data_size_t     sid_len;
-    /* VARARG(sid,SID); */
+    /* VARARG(sid,sid); */
     char __pad_12[4];
 };
 
@@ -6261,7 +6269,7 @@ union generic_reply
 
 /* ### protocol_version begin ### */
 
-#define SERVER_PROTOCOL_VERSION 741
+#define SERVER_PROTOCOL_VERSION 742
 
 /* ### protocol_version end ### */
 
diff --git a/server/change.c b/server/change.c
index a01d6894151..6477b457f74 100644
--- a/server/change.c
+++ b/server/change.c
@@ -364,7 +364,7 @@ static int dir_set_sd( struct object *obj, const struct security_descriptor *sd,
                        unsigned int set_info )
 {
     struct dir *dir = (struct dir *)obj;
-    const SID *owner;
+    const struct sid *owner;
     struct stat st;
     mode_t mode;
     int unix_fd;
@@ -383,7 +383,7 @@ static int dir_set_sd( struct object *obj, const struct security_descriptor *sd,
             set_error( STATUS_INVALID_SECURITY_DESCR );
             return 0;
         }
-        if (!obj->sd || !security_equal_sid( owner, sd_get_owner( obj->sd ) ))
+        if (!obj->sd || !equal_sid( owner, sd_get_owner( obj->sd ) ))
         {
             /* FIXME: get Unix uid and call fchown */
         }
diff --git a/server/file.c b/server/file.c
index f2f4f87b48b..eb2dc5696ed 100644
--- a/server/file.c
+++ b/server/file.c
@@ -243,7 +243,7 @@ static struct object *create_file( struct fd *root, const char *nameptr, data_si
 
     if (sd)
     {
-        const SID *owner = sd_get_owner( sd );
+        const struct sid *owner = sd_get_owner( sd );
         if (!owner)
             owner = token_get_user( current->process->token );
         mode = sd_to_mode( sd, owner );
@@ -306,7 +306,7 @@ static struct fd *file_get_fd( struct object *obj )
     return (struct fd *)grab_object( file->fd );
 }
 
-struct security_descriptor *mode_to_sd( mode_t mode, const SID *user, const SID *group )
+struct security_descriptor *mode_to_sd( mode_t mode, const struct sid *user, const struct sid *group )
 {
     struct security_descriptor *sd;
     unsigned char flags;
@@ -314,25 +314,21 @@ struct security_descriptor *mode_to_sd( mode_t mode, const SID *user, const SID
     struct ace *ace;
     struct acl *dacl;
     char *ptr;
-    const SID *world_sid = security_world_sid;
-    const SID *local_system_sid = security_local_system_sid;
 
-    dacl_size = sizeof(*dacl) + sizeof(*ace) + security_sid_len( local_system_sid );
-    if (mode & S_IRWXU) dacl_size += sizeof(*ace) + security_sid_len( user );
+    dacl_size = sizeof(*dacl) + sizeof(*ace) + sid_len( &local_system_sid );
+    if (mode & S_IRWXU) dacl_size += sizeof(*ace) + sid_len( user );
     if ((!(mode & S_IRUSR) && (mode & (S_IRGRP|S_IROTH))) ||
         (!(mode & S_IWUSR) && (mode & (S_IWGRP|S_IWOTH))) ||
         (!(mode & S_IXUSR) && (mode & (S_IXGRP|S_IXOTH))))
-        dacl_size += sizeof(*ace) + security_sid_len( user );
-    if (mode & S_IRWXO) dacl_size += sizeof(*ace) + security_sid_len( world_sid );
+        dacl_size += sizeof(*ace) + sid_len( user );
+    if (mode & S_IRWXO) dacl_size += sizeof(*ace) + sid_len( &world_sid );
 
-    sd = mem_alloc( sizeof(struct security_descriptor) +
-                    security_sid_len( user ) + security_sid_len( group ) +
-                    dacl_size );
+    sd = mem_alloc( sizeof(*sd) + sid_len( user ) + sid_len( group ) + dacl_size );
     if (!sd) return sd;
 
     sd->control = SE_DACL_PRESENT;
-    sd->owner_len = security_sid_len( user );
-    sd->group_len = security_sid_len( group );
+    sd->owner_len = sid_len( user );
+    sd->group_len = sid_len( group );
     sd->sacl_len = 0;
     sd->dacl_len = dacl_size;
 
@@ -358,7 +354,7 @@ struct security_descriptor *mode_to_sd( mode_t mode, const SID *user, const SID
     flags = (mode & S_IFDIR) ? OBJECT_INHERIT_ACE | CONTAINER_INHERIT_ACE : 0;
 
     /* always give FILE_ALL_ACCESS for Local System */
-    ace = set_ace( (struct ace *)(dacl + 1), local_system_sid,
+    ace = set_ace( (struct ace *)(dacl + 1), &local_system_sid,
                    ACCESS_ALLOWED_ACE_TYPE, flags, FILE_ALL_ACCESS );
 
     if (mode & S_IRWXU)
@@ -383,7 +379,7 @@ struct security_descriptor *mode_to_sd( mode_t mode, const SID *user, const SID
     if (mode & S_IRWXO)
     {
         /* appropriate access rights for Everyone */
-        ace = set_ace( ace_next( ace ), world_sid, ACCESS_ALLOWED_ACE_TYPE, flags, 0 );
+        ace = set_ace( ace_next( ace ), &world_sid, ACCESS_ALLOWED_ACE_TYPE, flags, 0 );
         if (mode & S_IROTH) ace->mask |= FILE_GENERIC_READ | FILE_GENERIC_EXECUTE;
         if (mode & S_IWOTH) ace->mask |= FILE_GENERIC_WRITE | DELETE | FILE_DELETE_CHILD;
     }
@@ -433,7 +429,7 @@ static mode_t file_access_to_mode( unsigned int access )
     return mode;
 }
 
-mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner )
+mode_t sd_to_mode( const struct security_descriptor *sd, const struct sid *owner )
 {
     mode_t new_mode = 0;
     mode_t bits_to_set = ~0;
@@ -448,7 +444,7 @@ mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner )
 
         for (i = 0; i < dacl->count; i++, ace = ace_next( ace ))
         {
-            const SID *sid = (const SID *)(ace + 1);
+            const struct sid *sid = (const struct sid *)(ace + 1);
 
             if (ace->flags & INHERIT_ONLY_ACE) continue;
 
@@ -456,7 +452,7 @@ mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner )
             switch (ace->type)
             {
                 case ACCESS_DENIED_ACE_TYPE:
-                    if (security_equal_sid( sid, security_world_sid ))
+                    if (equal_sid( sid, &world_sid ))
                     {
                         bits_to_set &= ~((mode << 6) | (mode << 3) | mode); /* all */
                     }
@@ -465,13 +461,13 @@ mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner )
                     {
                         bits_to_set &= ~((mode << 6) | (mode << 3));  /* user + group */
                     }
-                    else if (security_equal_sid( sid, owner ))
+                    else if (equal_sid( sid, owner ))
                     {
                         bits_to_set &= ~(mode << 6);  /* user only */
                     }
                     break;
                 case ACCESS_ALLOWED_ACE_TYPE:
-                    if (security_equal_sid( sid, security_world_sid ))
+                    if (equal_sid( sid, &world_sid ))
                     {
                         mode = (mode << 6) | (mode << 3) | mode;  /* all */
                         new_mode |= mode & bits_to_set;
@@ -484,7 +480,7 @@ mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner )
                         new_mode |= mode & bits_to_set;
                         bits_to_set &= ~mode;
                     }
-                    else if (security_equal_sid( sid, owner ))
+                    else if (equal_sid( sid, owner ))
                     {
                         mode = (mode << 6);  /* user only */
                         new_mode |= mode & bits_to_set;
@@ -505,7 +501,7 @@ static int file_set_sd( struct object *obj, const struct security_descriptor *sd
                         unsigned int set_info )
 {
     struct file *file = (struct file *)obj;
-    const SID *owner;
+    const struct sid *owner;
     struct stat st;
     mode_t mode;
     int unix_fd;
@@ -524,7 +520,7 @@ static int file_set_sd( struct object *obj, const struct security_descriptor *sd
             set_error( STATUS_INVALID_SECURITY_DESCR );
             return 0;
         }
-        if (!obj->sd || !security_equal_sid( owner, sd_get_owner( obj->sd ) ))
+        if (!obj->sd || !equal_sid( owner, sd_get_owner( obj->sd ) ))
         {
             /* FIXME: get Unix uid and call fchown */
         }
diff --git a/server/file.h b/server/file.h
index 1d830cd3d6f..9f9d4cd4e1a 100644
--- a/server/file.h
+++ b/server/file.h
@@ -164,8 +164,8 @@ extern int get_file_unix_fd( struct file *file );
 extern struct file *create_file_for_fd( int fd, unsigned int access, unsigned int sharing );
 extern struct file *create_file_for_fd_obj( struct fd *fd, unsigned int access, unsigned int sharing );
 extern void file_set_error(void);
-extern struct security_descriptor *mode_to_sd( mode_t mode, const SID *user, const SID *group );
-extern mode_t sd_to_mode( const struct security_descriptor *sd, const SID *owner );
+extern struct security_descriptor *mode_to_sd( mode_t mode, const struct sid *user, const struct sid *group );
+extern mode_t sd_to_mode( const struct security_descriptor *sd, const struct sid *owner );
 extern int is_file_executable( const char *name );
 
 /* file mapping functions */
diff --git a/server/handle.c b/server/handle.c
index c62dd6068a4..38ad80da267 100644
--- a/server/handle.c
+++ b/server/handle.c
@@ -737,7 +737,7 @@ DECL_HANDLER(get_security_object)
     unsigned int access = READ_CONTROL;
     struct security_descriptor req_sd;
     int present;
-    const SID *owner, *group;
+    const struct sid *owner, *group;
     const struct acl *sacl, *dacl;
     struct acl *label_acl = NULL;
 
diff --git a/server/object.c b/server/object.c
index 7b57a38aa84..907bc087444 100644
--- a/server/object.c
+++ b/server/object.c
@@ -543,7 +543,7 @@ int set_sd_defaults_from_token( struct object *obj, const struct security_descri
 {
     struct security_descriptor new_sd, *new_sd_ptr;
     int present;
-    const SID *owner = NULL, *group = NULL;
+    const struct sid *owner = NULL, *group = NULL;
     const struct acl *sacl, *dacl;
     struct acl *replaced_sacl = NULL;
     char *ptr;
@@ -565,7 +565,7 @@ int set_sd_defaults_from_token( struct object *obj, const struct security_descri
     else if (token)
     {
         owner = token_get_user( token );
-        new_sd.owner_len = security_sid_len( owner );
+        new_sd.owner_len = sid_len( owner );
     }
     else new_sd.owner_len = 0;
 
@@ -582,7 +582,7 @@ int set_sd_defaults_from_token( struct object *obj, const struct security_descri
     else if (token)
     {
         group = token_get_primary_group( token );
-        new_sd.group_len = security_sid_len( group );
+        new_sd.group_len = sid_len( group );
     }
     else new_sd.group_len = 0;
 
diff --git a/server/process.c b/server/process.c
index 8aea9deaa0e..65e2aa70de2 100644
--- a/server/process.c
+++ b/server/process.c
@@ -735,7 +735,7 @@ struct process *create_process( int fd, struct process *parent, unsigned int fla
     /* Assign a high security label to the token. The default would be medium
      * but Wine provides admin access to all applications right now so high
      * makes more sense for the time being. */
-    if (!token_assign_label( process->token, security_high_label_sid ))
+    if (!token_assign_label( process->token, &high_label_sid ))
         goto error;
 
     set_fd_events( process->msg_fd, POLLIN );  /* start listening to events */
@@ -825,8 +825,9 @@ static struct security_descriptor *process_get_sd( struct object *obj )
     {
         struct ace *ace;
         struct acl *dacl;
-        size_t users_sid_len = security_sid_len( security_domain_users_sid );
-        size_t admins_sid_len = security_sid_len( security_builtin_admins_sid );
+        struct sid *sid;
+        size_t users_sid_len = sid_len( &domain_users_sid );
+        size_t admins_sid_len = sid_len( &builtin_admins_sid );
         size_t dacl_len = sizeof(*dacl) + 2 * sizeof(*ace) + users_sid_len + admins_sid_len;
 
         process_default_sd = mem_alloc( sizeof(*process_default_sd) + admins_sid_len + users_sid_len
@@ -836,8 +837,9 @@ static struct security_descriptor *process_get_sd( struct object *obj )
         process_default_sd->group_len = users_sid_len;
         process_default_sd->sacl_len  = 0;
         process_default_sd->dacl_len  = dacl_len;
-        memcpy( process_default_sd + 1, security_builtin_admins_sid, admins_sid_len );
-        memcpy( (char *)(process_default_sd + 1) + admins_sid_len, security_domain_users_sid, users_sid_len );
+        sid = (struct sid *)(process_default_sd + 1);
+        sid = copy_sid( sid, &builtin_admins_sid );
+        sid = copy_sid( sid, &domain_users_sid );
 
         dacl = (struct acl *)((char *)(process_default_sd + 1) + admins_sid_len + users_sid_len);
         dacl->revision = ACL_REVISION;
@@ -845,9 +847,9 @@ static struct security_descriptor *process_get_sd( struct object *obj )
         dacl->size     = dacl_len;
         dacl->count    = 2;
         dacl->pad2     = 0;
-        ace = set_ace( ace_first( dacl ), security_domain_users_sid, ACCESS_ALLOWED_ACE_TYPE,
+        ace = set_ace( ace_first( dacl ), &domain_users_sid, ACCESS_ALLOWED_ACE_TYPE,
                        INHERIT_ONLY_ACE | CONTAINER_INHERIT_ACE, GENERIC_READ );
-        set_ace( ace_next( ace ), security_builtin_admins_sid, ACCESS_ALLOWED_ACE_TYPE, 0, PROCESS_ALL_ACCESS );
+        set_ace( ace_next( ace ), &builtin_admins_sid, ACCESS_ALLOWED_ACE_TYPE, 0, PROCESS_ALL_ACCESS );
     }
     return process_default_sd;
 }
diff --git a/server/protocol.def b/server/protocol.def
index 8082efcb602..abd93a70768 100644
--- a/server/protocol.def
+++ b/server/protocol.def
@@ -401,6 +401,14 @@ struct acl
     unsigned short pad2;
 };
 
+struct sid
+{
+    unsigned char revision;
+    unsigned char sub_count;
+    unsigned char id_auth[6];
+    unsigned int  sub_auth[15];
+};
+
 typedef struct
 {
     unsigned int read;
@@ -418,8 +426,8 @@ struct security_descriptor
     data_size_t  group_len;
     data_size_t  sacl_len;
     data_size_t  dacl_len;
-    /* VARARG(owner,SID); */
-    /* VARARG(group,SID); */
+    /* VARARG(owner,sid); */
+    /* VARARG(group,sid); */
     /* VARARG(sacl,acl); */
     /* VARARG(dacl,acl); */
 };
@@ -451,7 +459,7 @@ struct token_groups
 {
     unsigned int count;
     /* unsigned int attributes[count]; */
-    /* VARARG(sids,SID); */
+    /* VARARG(sids,sid); */
 };
 
 enum select_op
@@ -3138,7 +3146,7 @@ enum caret_state
     unsigned int  flags;           /* flags */
     data_size_t   privileges_size; /* size of privileges */
     VARARG(privileges,luid_attr,privileges_size); /* privileges to remove from new token */
-    VARARG(disable_sids,SID);      /* array of groups to remove from new token */
+    VARARG(disable_sids,sid);      /* array of groups to remove from new token */
 @REPLY
     obj_handle_t  new_handle;      /* filtered handle */
 @END
@@ -3160,7 +3168,7 @@ enum caret_state
     unsigned int    which_sid;    /* which SID to retrieve from the token */
 @REPLY
     data_size_t     sid_len;      /* length needed to store sid */
-    VARARG(sid,SID);              /* the sid specified by which_sid from the token */
+    VARARG(sid,sid);              /* the sid specified by which_sid from the token */
 @END
 
 @REQ(get_token_groups)
diff --git a/server/registry.c b/server/registry.c
index 8187c12d5ce..93e8a309593 100644
--- a/server/registry.c
+++ b/server/registry.c
@@ -371,8 +371,9 @@ static struct security_descriptor *key_get_sd( struct object *obj )
     {
         struct acl *dacl;
         struct ace *ace;
-        size_t users_sid_len = security_sid_len( security_builtin_users_sid );
-        size_t admins_sid_len = security_sid_len( security_builtin_admins_sid );
+        struct sid *sid;
+        size_t users_sid_len = sid_len( &builtin_users_sid );
+        size_t admins_sid_len = sid_len( &builtin_admins_sid );
         size_t dacl_len = sizeof(*dacl) + 2 * sizeof(*ace) + users_sid_len + admins_sid_len;
 
         key_default_sd = mem_alloc( sizeof(*key_default_sd) + 2 * admins_sid_len + dacl_len );
@@ -381,8 +382,9 @@ static struct security_descriptor *key_get_sd( struct object *obj )
         key_default_sd->group_len = admins_sid_len;
         key_default_sd->sacl_len  = 0;
         key_default_sd->dacl_len  = dacl_len;
-        memcpy( key_default_sd + 1, security_builtin_admins_sid, admins_sid_len );
-        memcpy( (char *)(key_default_sd + 1) + admins_sid_len, security_builtin_admins_sid, admins_sid_len );
+        sid = (struct sid *)(key_default_sd + 1);
+        sid = copy_sid( sid, &builtin_admins_sid );
+        sid = copy_sid( sid, &builtin_admins_sid );
 
         dacl = (struct acl *)((char *)(key_default_sd + 1) + 2 * admins_sid_len);
         dacl->revision = ACL_REVISION;
@@ -390,9 +392,9 @@ static struct security_descriptor *key_get_sd( struct object *obj )
         dacl->size     = dacl_len;
         dacl->count    = 2;
         dacl->pad2     = 0;
-        ace = set_ace( ace_first( dacl ), security_builtin_users_sid, ACCESS_ALLOWED_ACE_TYPE,
+        ace = set_ace( ace_first( dacl ), &builtin_users_sid, ACCESS_ALLOWED_ACE_TYPE,
                        INHERIT_ONLY_ACE | CONTAINER_INHERIT_ACE, GENERIC_READ );
-        set_ace( ace_next( ace ), security_builtin_admins_sid, ACCESS_ALLOWED_ACE_TYPE, 0, KEY_ALL_ACCESS );
+        set_ace( ace_next( ace ), &builtin_admins_sid, ACCESS_ALLOWED_ACE_TYPE, 0, KEY_ALL_ACCESS );
     }
     return key_default_sd;
 }
@@ -1791,17 +1793,17 @@ static int load_init_registry_from_file( const char *filename, struct key *key )
     return (f != NULL);
 }
 
-static WCHAR *format_user_registry_path( const SID *sid, struct unicode_str *path )
+static WCHAR *format_user_registry_path( const struct sid *sid, struct unicode_str *path )
 {
-    char buffer[7 + 11 + 11 + 11 * SID_MAX_SUB_AUTHORITIES], *p = buffer;
+    char buffer[7 + 11 + 11 + 11 * ARRAY_SIZE(sid->sub_auth)], *p = buffer;
     unsigned int i;
 
-    p += sprintf( p, "User\\S-%u-%u", sid->Revision,
-                  MAKELONG( MAKEWORD( sid->IdentifierAuthority.Value[5],
-                                      sid->IdentifierAuthority.Value[4] ),
-                            MAKEWORD( sid->IdentifierAuthority.Value[3],
-                                      sid->IdentifierAuthority.Value[2] )));
-    for (i = 0; i < sid->SubAuthorityCount; i++) p += sprintf( p, "-%u", sid->SubAuthority[i] );
+    p += sprintf( p, "User\\S-%u-%u", sid->revision,
+                  ((unsigned int)sid->id_auth[2] << 24) |
+                  ((unsigned int)sid->id_auth[3] << 16) |
+                  ((unsigned int)sid->id_auth[4] << 8) |
+                  ((unsigned int)sid->id_auth[5]) );
+    for (i = 0; i < sid->sub_count; i++) p += sprintf( p, "-%u", sid->sub_auth[i] );
     return ascii_to_unicode_str( buffer, path );
 }
 
@@ -1900,7 +1902,7 @@ void init_registry(void)
     /* load user.reg into HKEY_CURRENT_USER */
 
     /* FIXME: match default user in token.c. should get from process token instead */
-    current_user_path = format_user_registry_path( security_local_user_sid, &current_user_str );
+    current_user_path = format_user_registry_path( &local_user_sid, &current_user_str );
     if (!current_user_path ||
         !(hkcu = create_key_recursive( root_key, &current_user_str, current_time )))
         fatal_error( "could not create HKEY_CURRENT_USER registry key\n" );
diff --git a/server/security.h b/server/security.h
index 5fd9cd3269b..fa91b81b77c 100644
--- a/server/security.h
+++ b/server/security.h
@@ -44,13 +44,13 @@ extern const struct luid SeManageVolumePrivilege;
 extern const struct luid SeImpersonatePrivilege;
 extern const struct luid SeCreateGlobalPrivilege;
 
-extern const PSID security_world_sid;
-extern const PSID security_local_user_sid;
-extern const PSID security_local_system_sid;
-extern const PSID security_builtin_users_sid;
-extern const PSID security_builtin_admins_sid;
-extern const PSID security_domain_users_sid;
-extern const PSID security_high_label_sid;
+extern const struct sid world_sid;
+extern const struct sid local_user_sid;
+extern const struct sid local_system_sid;
+extern const struct sid builtin_users_sid;
+extern const struct sid builtin_admins_sid;
+extern const struct sid domain_users_sid;
+extern const struct sid high_label_sid;
 
 struct ace
 {
@@ -64,19 +64,19 @@ struct ace
 
 extern struct token *get_token_obj( struct process *process, obj_handle_t handle, unsigned int access );
 extern struct token *token_create_admin( unsigned primary, int impersonation_level, int elevation, unsigned int session_id );
-extern int token_assign_label( struct token *token, PSID label );
+extern int token_assign_label( struct token *token, const struct sid *label );
 extern struct token *token_duplicate( struct token *src_token, unsigned primary,
                                       int impersonation_level, const struct security_descriptor *sd,
                                       const struct luid_attr *remove_privs, unsigned int remove_priv_count,
-                                      const SID *remove_groups, unsigned int remove_group_count );
+                                      const struct sid *remove_groups, unsigned int remove_group_count );
 extern int token_check_privileges( struct token *token, int all_required,
                                    const struct luid_attr *reqprivs,
                                    unsigned int count, struct luid_attr *usedprivs );
 extern const struct acl *token_get_default_dacl( struct token *token );
-extern const SID *token_get_user( struct token *token );
-extern const SID *token_get_primary_group( struct token *token );
+extern const struct sid *token_get_user( struct token *token );
+extern const struct sid *token_get_primary_group( struct token *token );
 extern unsigned int token_get_session_id( struct token *token );
-extern int token_sid_present( struct token *token, const SID *sid, int deny);
+extern int token_sid_present( struct token *token, const struct sid *sid, int deny );
 
 static inline struct ace *ace_first( const struct acl *acl )
 {
@@ -88,35 +88,40 @@ static inline struct ace *ace_next( const struct ace *ace )
     return (struct ace *)((char *)ace + ace->size);
 }
 
-static inline size_t security_sid_len( const SID *sid )
+static inline size_t sid_len( const struct sid *sid )
 {
-    return offsetof( SID, SubAuthority[sid->SubAuthorityCount] );
+    return offsetof( struct sid, sub_auth[sid->sub_count] );
 }
 
-static inline int security_equal_sid( const SID *sid1, const SID *sid2 )
+static inline int equal_sid( const struct sid *sid1, const struct sid *sid2 )
 {
-    return ((sid1->SubAuthorityCount == sid2->SubAuthorityCount) &&
-            !memcmp( sid1, sid2, security_sid_len( sid1 )));
+    return ((sid1->sub_count == sid2->sub_count) && !memcmp( sid1, sid2, sid_len( sid1 )));
 }
 
-static inline int sid_valid_size( const SID *sid, data_size_t size )
+static inline void *copy_sid( struct sid *dst, const struct sid *src )
 {
-    return (size >= offsetof( SID, SubAuthority[0] ) && size >= security_sid_len( sid ));
+    memcpy( dst, src, sid_len( src ));
+    return (char *)dst + sid_len( src );
 }
 
-static inline struct ace *set_ace( struct ace *ace, const SID *sid, unsigned char type,
+static inline int sid_valid_size( const struct sid *sid, data_size_t size )
+{
+    return (size >= offsetof( struct sid, sub_auth[0] ) && size >= sid_len( sid ));
+}
+
+static inline struct ace *set_ace( struct ace *ace, const struct sid *sid, unsigned char type,
                                    unsigned char flags, unsigned int mask )
 {
     ace->type  = type;
     ace->flags = flags;
-    ace->size  = sizeof(*ace) + security_sid_len( sid );
+    ace->size  = sizeof(*ace) + sid_len( sid );
     ace->mask  = mask;
-    memcpy( ace + 1, sid, security_sid_len( sid ));
+    memcpy( ace + 1, sid, sid_len( sid ));
     return ace;
 }
 
 extern void security_set_thread_token( struct thread *thread, obj_handle_t handle );
-extern const SID *security_unix_uid_to_sid( uid_t uid );
+extern const struct sid *security_unix_uid_to_sid( uid_t uid );
 extern int check_object_access( struct token *token, struct object *obj, unsigned int *access );
 
 static inline int thread_single_check_privilege( struct thread *thread, struct luid priv )
@@ -161,19 +166,19 @@ static inline const struct acl *sd_get_sacl( const struct security_descriptor *s
 }
 
 /* gets the owner from a security descriptor */
-static inline const SID *sd_get_owner( const struct security_descriptor *sd )
+static inline const struct sid *sd_get_owner( const struct security_descriptor *sd )
 {
     if (sd->owner_len)
-        return (const SID *)(sd + 1);
+        return (const struct 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 )
+static inline const struct sid *sd_get_group( const struct security_descriptor *sd )
 {
     if (sd->group_len)
-        return (const SID *)((const char *)(sd + 1) + sd->owner_len);
+        return (const struct sid *)((const char *)(sd + 1) + sd->owner_len);
     else
         return NULL;
 }
diff --git a/server/token.c b/server/token.c
index 49168a77e10..8686d0f69a7 100644
--- a/server/token.c
+++ b/server/token.c
@@ -66,38 +66,23 @@ const struct luid SeCreateGlobalPrivilege         = { 30, 0 };
 
 struct sid_attrs
 {
-    const SID   *sid;
-    unsigned int attrs;
+    const struct sid *sid;
+    unsigned int      attrs;
 };
 
-#define SID_N(n) struct /* same fields as struct SID */ \
-    { \
-        BYTE Revision; \
-        BYTE SubAuthorityCount; \
-        SID_IDENTIFIER_AUTHORITY IdentifierAuthority; \
-        DWORD SubAuthority[n]; \
-    }
+const struct sid world_sid = { SID_REVISION, 1, SECURITY_WORLD_SID_AUTHORITY, { SECURITY_WORLD_RID } };
+const struct sid local_system_sid = { SID_REVISION, 1, SECURITY_NT_AUTHORITY, { SECURITY_LOCAL_SYSTEM_RID } };
+const struct sid high_label_sid = { SID_REVISION, 1, SECURITY_MANDATORY_LABEL_AUTHORITY, { SECURITY_MANDATORY_HIGH_RID } };
+const struct sid local_user_sid = { SID_REVISION, 5, SECURITY_NT_AUTHORITY, { SECURITY_NT_NON_UNIQUE, 0, 0, 0, 1000 } };
+const struct sid builtin_admins_sid = { SID_REVISION, 2, SECURITY_NT_AUTHORITY, { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_ADMINS } };
+const struct sid builtin_users_sid = { SID_REVISION, 2, SECURITY_NT_AUTHORITY, { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_USERS } };
+const struct sid domain_users_sid = { SID_REVISION, 5, SECURITY_NT_AUTHORITY, { SECURITY_NT_NON_UNIQUE, 0, 0, 0, DOMAIN_GROUP_RID_USERS } };
 
-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 anonymous_logon_sid = { SID_REVISION, 1, { SECURITY_NT_AUTHORITY }, { SECURITY_ANONYMOUS_LOGON_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 SID high_label_sid = { SID_REVISION, 1, { SECURITY_MANDATORY_LABEL_AUTHORITY }, { SECURITY_MANDATORY_HIGH_RID } };
-static const SID_N(5) local_user_sid = { SID_REVISION, 5, { SECURITY_NT_AUTHORITY }, { SECURITY_NT_NON_UNIQUE, 0, 0, 0, 1000 } };
-static const SID_N(2) builtin_admins_sid = { SID_REVISION, 2, { SECURITY_NT_AUTHORITY }, { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_ADMINS } };
-static const SID_N(2) builtin_users_sid = { SID_REVISION, 2, { SECURITY_NT_AUTHORITY }, { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_USERS } };
-static const SID_N(3) builtin_logon_sid = { SID_REVISION, 3, { SECURITY_NT_AUTHORITY }, { SECURITY_LOGON_IDS_RID, 0, 0 } };
-static const SID_N(5) domain_users_sid = { SID_REVISION, 5, { SECURITY_NT_AUTHORITY }, { SECURITY_NT_NON_UNIQUE, 0, 0, 0, DOMAIN_GROUP_RID_USERS } };
-
-const PSID security_world_sid = (PSID)&world_sid;
-const PSID security_local_system_sid = (PSID)&local_system_sid;
-const PSID security_local_user_sid = (PSID)&local_user_sid;
-const PSID security_builtin_admins_sid = (PSID)&builtin_admins_sid;
-const PSID security_builtin_users_sid = (PSID)&builtin_users_sid;
-const PSID security_domain_users_sid = (PSID)&domain_users_sid;
-const PSID security_high_label_sid = (PSID)&high_label_sid;
+static const struct sid local_sid = { SID_REVISION, 1, SECURITY_LOCAL_SID_AUTHORITY, { SECURITY_LOCAL_RID } };
+static const struct sid interactive_sid = { SID_REVISION, 1, SECURITY_NT_AUTHORITY, { SECURITY_INTERACTIVE_RID } };
+static const struct sid anonymous_logon_sid = { SID_REVISION, 1, SECURITY_NT_AUTHORITY, { SECURITY_ANONYMOUS_LOGON_RID } };
+static const struct sid authenticated_user_sid = { SID_REVISION, 1, SECURITY_NT_AUTHORITY, { SECURITY_AUTHENTICATED_USER_RID } };
+static const struct sid builtin_logon_sid = { SID_REVISION, 3, SECURITY_NT_AUTHORITY, { SECURITY_LOGON_IDS_RID, 0, 0 } };
 
 static struct luid prev_luid_value = { 1000, 0 };
 
@@ -123,13 +108,12 @@ struct token
     struct luid    modified_id;     /* new id allocated every time token is modified */
     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 */
-    SID           *owner;           /* SID of owner (points to user or one of groups) */
-    SID           *primary_group;   /* SID of user's primary group (points to one of groups) */
+    struct sid    *user;            /* SID of user this token represents */
+    struct sid    *owner;           /* SID of owner (points to user or one of groups) */
+    struct sid    *primary_group;   /* SID of user's primary group (points to one of groups) */
     unsigned int   primary;         /* is this a primary or impersonation token? */
     unsigned int   session_id;      /* token session id */
     struct acl    *default_dacl;    /* the default DACL to assign to objects created by this user */
-    TOKEN_SOURCE   source;          /* source of the token */
     int            impersonation_level; /* impersonation level this token is capable of if non-primary token */
     int            elevation;       /* elevation type */
 };
@@ -152,7 +136,7 @@ struct group
     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;
+    struct sid  sid;
 };
 
 static void token_dump( struct object *obj, int verbose );
@@ -190,19 +174,6 @@ static void token_dump( struct object *obj, int verbose )
              token->token_id.low_part, token->primary, token->impersonation_level );
 }
 
-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;
-}
-
 void security_set_thread_token( struct thread *thread, obj_handle_t handle )
 {
     if (!handle)
@@ -226,11 +197,11 @@ void security_set_thread_token( struct thread *thread, obj_handle_t handle )
     }
 }
 
-const SID *security_unix_uid_to_sid( uid_t uid )
+const struct sid *security_unix_uid_to_sid( uid_t uid )
 {
     /* very simple mapping: either the current user or not the current user */
     if (uid == getuid())
-        return (const SID *)&local_user_sid;
+        return &local_user_sid;
     else
         return &anonymous_logon_sid;
 }
@@ -260,21 +231,20 @@ static int acl_is_valid( const struct acl *acl, data_size_t size )
         default:
             return FALSE;
         }
-        if (!sid_valid_size( (const SID *)(ace + 1), ace->size - sizeof(*ace) )) return FALSE;
+        if (!sid_valid_size( (const struct sid *)(ace + 1), ace->size - sizeof(*ace) )) return FALSE;
     }
     return TRUE;
 }
 
-static unsigned int get_sid_count( const SID *sid, data_size_t size )
+static unsigned int get_sid_count( const struct sid *sid, data_size_t size )
 {
     unsigned int count;
 
-    for (count = 0; size >= sizeof(SID) && security_sid_len( sid ) <= size; count++)
+    for (count = 0; sid_valid_size( sid, size ); count++)
     {
-        size -= security_sid_len( sid );
-        sid = (const SID *)((char *)sid + security_sid_len( sid ));
+        size -= sid_len( sid );
+        sid = (const struct sid *)((char *)sid + sid_len( sid ));
     }
-
     return count;
 }
 
@@ -283,8 +253,8 @@ static unsigned int get_sid_count( const SID *sid, data_size_t size )
 int sd_is_valid( const struct security_descriptor *sd, data_size_t size )
 {
     size_t offset = sizeof(struct security_descriptor);
-    const SID *group;
-    const SID *owner;
+    const struct sid *group;
+    const struct sid *owner;
     const struct acl *sacl;
     const struct acl *dacl;
     int dummy;
@@ -292,27 +262,15 @@ int sd_is_valid( const struct security_descriptor *sd, data_size_t size )
     if (size < offset)
         return FALSE;
 
-    if ((sd->owner_len >= FIELD_OFFSET(SID, SubAuthority[255])) ||
-        (offset + sd->owner_len > size))
-        return FALSE;
+    if (sd->owner_len >= offsetof(struct sid, sub_auth[255]) || offset + sd->owner_len > size) return FALSE;
     owner = sd_get_owner( sd );
-    if (owner)
-    {
-        if ((sd->owner_len < sizeof(SID)) || (security_sid_len( owner ) > sd->owner_len))
-            return FALSE;
-    }
     offset += sd->owner_len;
+    if (owner && !sid_valid_size( owner, sd->owner_len )) return FALSE;
 
-    if ((sd->group_len >= FIELD_OFFSET(SID, SubAuthority[255])) ||
-        (offset + sd->group_len > size))
-        return FALSE;
+    if (sd->group_len >= offsetof(struct sid, sub_auth[255]) || offset + sd->group_len > size) return FALSE;
     group = sd_get_group( sd );
-    if (group)
-    {
-        if ((sd->group_len < sizeof(SID)) || (security_sid_len( group ) > sd->group_len))
-            return FALSE;
-    }
     offset += sd->group_len;
+    if (group && !sid_valid_size( group, sd->group_len )) return FALSE;
 
     if ((sd->sacl_len >= MAX_ACL_LEN) || (offset + sd->sacl_len > size))
         return FALSE;
@@ -517,11 +475,10 @@ static void token_destroy( struct object *obj )
  *  modified_id may be NULL, indicating that a new modified_id luid should be
  *   allocated.
  */
-static struct token *create_token( unsigned int primary, unsigned int session_id, const SID *user,
+static struct token *create_token( unsigned int primary, unsigned int session_id, const struct sid *user,
                                    const struct sid_attrs *groups, unsigned int group_count,
                                    const struct luid_attr *privs, unsigned int priv_count,
-                                   const struct acl *default_dacl, TOKEN_SOURCE source,
-                                   const struct luid *modified_id,
+                                   const struct acl *default_dacl, const struct luid *modified_id,
                                    int impersonation_level, int elevation )
 {
     struct token *token = alloc_object( &token_ops );
@@ -548,7 +505,7 @@ static struct token *create_token( unsigned int primary, unsigned int session_id
         token->elevation = elevation;
 
         /* copy user */
-        token->user = memdup( user, security_sid_len( user ));
+        token->user = memdup( user, sid_len( user ));
         if (!token->user)
         {
             release_object( token );
@@ -558,7 +515,7 @@ static struct token *create_token( unsigned int primary, unsigned int session_id
         /* copy groups */
         for (i = 0; i < group_count; i++)
         {
-            size_t size = FIELD_OFFSET( struct group, sid.SubAuthority[groups[i].sid->SubAuthorityCount] );
+            size_t size = offsetof( struct group, sid.sub_auth[groups[i].sid->sub_count] );
             struct group *group = mem_alloc( size );
 
             if (!group)
@@ -566,7 +523,7 @@ static struct token *create_token( unsigned int primary, unsigned int session_id
                 release_object( token );
                 return NULL;
             }
-            memcpy( &group->sid, groups[i].sid, security_sid_len( groups[i].sid ));
+            copy_sid( &group->sid, groups[i].sid );
             group->enabled = TRUE;
             group->def = TRUE;
             group->logon = (groups[i].attrs & SE_GROUP_LOGON_ID) != 0;
@@ -604,20 +561,18 @@ static struct token *create_token( unsigned int primary, unsigned int session_id
                 return NULL;
             }
         }
-
-        token->source = source;
     }
     return token;
 }
 
-static int filter_group( struct group *group, const SID *filter, unsigned int count )
+static int filter_group( struct group *group, const struct sid *filter, unsigned int count )
 {
     unsigned int i;
 
     for (i = 0; i < count; i++)
     {
-        if (security_equal_sid( &group->sid, filter )) return 1;
-        filter = (const SID *)((char *)filter + security_sid_len( filter ));
+        if (equal_sid( &group->sid, filter )) return 1;
+        filter = (const struct sid *)((char *)filter + sid_len( filter ));
     }
 
     return 0;
@@ -636,7 +591,7 @@ static int filter_privilege( struct privilege *privilege, const struct luid_attr
 struct token *token_duplicate( struct token *src_token, unsigned primary,
                                int impersonation_level, const struct security_descriptor *sd,
                                const struct luid_attr *remove_privs, unsigned int remove_priv_count,
-                               const SID *remove_groups, unsigned int remove_group_count)
+                               const struct sid *remove_groups, unsigned int remove_group_count)
 {
     const struct luid *modified_id =
         primary || (impersonation_level == src_token->impersonation_level) ?
@@ -655,8 +610,7 @@ struct token *token_duplicate( struct token *src_token, unsigned primary,
     }
 
     token = create_token( primary, src_token->session_id, src_token->user, NULL, 0,
-                          NULL, 0, src_token->default_dacl,
-                          src_token->source, modified_id,
+                          NULL, 0, src_token->default_dacl, modified_id,
                           impersonation_level, src_token->elevation );
     if (!token) return token;
 
@@ -664,7 +618,7 @@ struct token *token_duplicate( struct token *src_token, unsigned primary,
     token->primary_group = NULL;
     LIST_FOR_EACH_ENTRY( group, &src_token->groups, struct group, entry )
     {
-        size_t size = FIELD_OFFSET( struct group, sid.SubAuthority[group->sid.SubAuthorityCount] );
+        size_t size = offsetof( struct group, sid.sub_auth[group->sid.sub_count] );
         struct group *newgroup = mem_alloc( size );
         if (!newgroup)
         {
@@ -704,12 +658,12 @@ struct token *token_duplicate( struct token *src_token, unsigned primary,
     return token;
 }
 
-static struct acl *create_default_dacl( const SID *user )
+static struct acl *create_default_dacl( const struct sid *user )
 {
     struct ace *ace;
     struct acl *default_dacl;
     size_t default_dacl_size = sizeof(*default_dacl) + 2 * sizeof(*ace) +
-                               sizeof(local_system_sid) + security_sid_len( user );
+                               sid_len( &local_system_sid ) + sid_len( user );
 
     default_dacl = mem_alloc( default_dacl_size );
     if (!default_dacl) return NULL;
@@ -735,13 +689,13 @@ struct sid_data
     unsigned int subauth[MAX_SUBAUTH_COUNT];
 };
 
-static struct security_descriptor *create_security_label_sd( struct token *token, PSID label_sid )
+static struct security_descriptor *create_security_label_sd( struct token *token, const struct sid *label_sid )
 {
-    size_t sid_len = security_sid_len( label_sid ), sacl_size, sd_size;
+    size_t sid_size = sid_len( label_sid ), sacl_size, sd_size;
     struct security_descriptor *sd;
     struct acl *sacl;
 
-    sacl_size = sizeof(*sacl) + sizeof(struct ace) + sid_len;
+    sacl_size = sizeof(*sacl) + sizeof(struct ace) + sid_size;
     sd_size = sizeof(struct security_descriptor) + sacl_size;
     if (!(sd = mem_alloc( sd_size )))
         return NULL;
@@ -765,7 +719,7 @@ static struct security_descriptor *create_security_label_sd( struct token *token
     return sd;
 }
 
-int token_assign_label( struct token *token, PSID label )
+int token_assign_label( struct token *token, const struct sid *label )
 {
     struct security_descriptor *sd;
     int ret = 0;
@@ -787,75 +741,57 @@ struct token *get_token_obj( struct process *process, obj_handle_t handle, unsig
 struct token *token_create_admin( unsigned primary, int impersonation_level, int elevation, unsigned int session_id )
 {
     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 };
+    struct sid alias_admins_sid = { SID_REVISION, 2, SECURITY_NT_AUTHORITY, { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_ADMINS }};
+    struct sid alias_users_sid = { SID_REVISION, 2, SECURITY_NT_AUTHORITY, { SECURITY_BUILTIN_DOMAIN_RID, DOMAIN_ALIAS_RID_USERS }};
     /* on Windows, this value changes every time the user logs on */
-    static const unsigned int logon_subauth[] = { SECURITY_LOGON_IDS_RID, 0, 1 /* FIXME: should be randomly generated when tokens are inherited by new processes */ };
-    PSID alias_admins_sid;
-    PSID alias_users_sid;
-    PSID logon_sid;
-    const SID *user_sid = security_unix_uid_to_sid( getuid() );
+    struct sid logon_sid = { SID_REVISION, 3, SECURITY_NT_AUTHORITY, { SECURITY_LOGON_IDS_RID, 0, 1 /* FIXME: should be randomly generated when tokens are inherited by new processes */ }};
+    const struct sid *user_sid = security_unix_uid_to_sid( getuid() );
     struct acl *default_dacl = create_default_dacl( user_sid );
-
-    alias_admins_sid = security_sid_alloc( &nt_authority, ARRAY_SIZE( alias_admins_subauth ),
-                                           alias_admins_subauth );
-    alias_users_sid = security_sid_alloc( &nt_authority, ARRAY_SIZE( alias_users_subauth ),
-                                          alias_users_subauth );
-    logon_sid = security_sid_alloc( &nt_authority, ARRAY_SIZE( logon_subauth ), logon_subauth );
-
-    if (alias_admins_sid && alias_users_sid && logon_sid && default_dacl)
+    const struct luid_attr admin_privs[] =
     {
-        const struct luid_attr admin_privs[] =
-        {
-            { SeChangeNotifyPrivilege        , SE_PRIVILEGE_ENABLED },
-            { SeTcbPrivilege                 , 0                    },
-            { 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          , SE_PRIVILEGE_ENABLED },
-            { 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 struct sid_attrs admin_groups[] =
-        {
-            { &world_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
-            { &local_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
-            { &interactive_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
-            { &authenticated_user_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
-            { (SID *)&domain_users_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY|SE_GROUP_OWNER },
-            { alias_admins_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY|SE_GROUP_OWNER },
-            { alias_users_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
-            { logon_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY|SE_GROUP_LOGON_ID },
-        };
-        static const TOKEN_SOURCE admin_source = {"SeMgr", {0, 0}};
-        token = create_token( primary, session_id, user_sid, admin_groups, ARRAY_SIZE( admin_groups ),
-                              admin_privs, ARRAY_SIZE( admin_privs ), default_dacl,
-                              admin_source, NULL, impersonation_level, elevation );
-        /* we really need a primary group */
-        assert( token->primary_group );
-    }
+        { SeChangeNotifyPrivilege, SE_PRIVILEGE_ENABLED },
+        { SeTcbPrivilege, 0 },
+        { 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, SE_PRIVILEGE_ENABLED },
+        { 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 struct sid_attrs admin_groups[] =
+    {
+        { &world_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
+        { &local_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
+        { &interactive_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
+        { &authenticated_user_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
+        { &domain_users_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY|SE_GROUP_OWNER },
+        { &alias_admins_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY|SE_GROUP_OWNER },
+        { &alias_users_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY },
+        { &logon_sid, SE_GROUP_ENABLED|SE_GROUP_ENABLED_BY_DEFAULT|SE_GROUP_MANDATORY|SE_GROUP_LOGON_ID },
+    };
+
+    token = create_token( primary, session_id, user_sid, admin_groups, ARRAY_SIZE( admin_groups ),
+                          admin_privs, ARRAY_SIZE( admin_privs ), default_dacl,
+                          NULL, impersonation_level, elevation );
+    /* we really need a primary group */
+    assert( token->primary_group );
 
-    free( logon_sid );
-    free( alias_admins_sid );
-    free( alias_users_sid );
     free( default_dacl );
-
     return token;
 }
 
@@ -944,18 +880,17 @@ int token_check_privileges( struct token *token, int all_required, const struct
         return (enabled_count > 0);
 }
 
-int token_sid_present( struct token *token, const SID *sid, int deny )
+int token_sid_present( struct token *token, const struct sid *sid, int deny )
 {
     struct group *group;
 
-    if (security_equal_sid( token->user, sid )) return TRUE;
+    if (equal_sid( token->user, sid )) return TRUE;
 
     LIST_FOR_EACH_ENTRY( group, &token->groups, struct group, entry )
     {
         if (!group->enabled) continue;
         if (group->deny_only && !deny) continue;
-
-        if (security_equal_sid( &group->sid, sid )) return TRUE;
+        if (equal_sid( &group->sid, sid )) return TRUE;
     }
 
     return FALSE;
@@ -982,7 +917,7 @@ static unsigned int token_access_check( struct token *token,
     const struct acl *dacl;
     int dacl_present;
     const struct ace *ace;
-    const SID *owner;
+    const struct sid *owner;
 
     /* assume no access rights */
     *granted_access = 0;
@@ -1068,7 +1003,7 @@ static unsigned int token_access_check( struct token *token,
     /* 4: Grant rights according to the DACL */
     for (i = 0, ace = ace_first( dacl ); i < dacl->count; i++, ace = ace_next( ace ))
     {
-        const SID *sid = (const SID *)(ace + 1);
+        const struct sid *sid = (const struct sid *)(ace + 1);
 
         if (ace->flags & INHERIT_ONLY_ACE) continue;
 
@@ -1123,12 +1058,12 @@ const struct acl *token_get_default_dacl( struct token *token )
     return token->default_dacl;
 }
 
-const SID *token_get_user( struct token *token )
+const struct sid *token_get_user( struct token *token )
 {
     return token->user;
 }
 
-const SID *token_get_primary_group( struct token *token )
+const struct sid *token_get_primary_group( struct token *token )
 {
     return token->primary_group;
 }
@@ -1311,11 +1246,11 @@ DECL_HANDLER(filter_token)
     {
         const struct luid_attr *filter_privileges = get_req_data();
         unsigned int priv_count, group_count;
-        const SID *filter_groups;
+        const struct sid *filter_groups;
         struct token *token;
 
         priv_count = min( req->privileges_size, get_req_data_size() ) / sizeof(struct luid_attr);
-        filter_groups = (const SID *)((char *)filter_privileges + priv_count * sizeof(struct luid_attr));
+        filter_groups = (const struct sid *)((char *)filter_privileges + priv_count * sizeof(struct luid_attr));
         group_count = get_sid_count( filter_groups, get_req_data_size() - priv_count * sizeof(struct luid_attr) );
 
         token = token_duplicate( src_token, src_token->primary, src_token->impersonation_level, NULL,
@@ -1418,7 +1353,7 @@ DECL_HANDLER(get_token_sid)
 
     if ((token = (struct token *)get_handle_obj( current->process, req->handle, TOKEN_QUERY, &token_ops )))
     {
-        const SID *sid = NULL;
+        const struct sid *sid = NULL;
 
         switch (req->which_sid)
         {
@@ -1433,7 +1368,7 @@ DECL_HANDLER(get_token_sid)
             sid = token->owner;
             break;
         case TokenLogonSid:
-            sid = (const SID *)&builtin_logon_sid;
+            sid = &builtin_logon_sid;
             break;
         default:
             set_error( STATUS_INVALID_PARAMETER );
@@ -1442,7 +1377,7 @@ DECL_HANDLER(get_token_sid)
 
         if (sid)
         {
-            reply->sid_len = security_sid_len( sid );
+            reply->sid_len = sid_len( sid );
             if (reply->sid_len <= get_reply_max_size()) set_reply_data( sid, reply->sid_len );
             else set_error( STATUS_BUFFER_TOO_SMALL );
         }
@@ -1469,7 +1404,7 @@ DECL_HANDLER(get_token_groups)
         LIST_FOR_EACH_ENTRY( group, &token->groups, const struct group, entry )
         {
             group_count++;
-            sid_size += security_sid_len( &group->sid );
+            sid_size += sid_len( &group->sid );
         }
         size_needed += sid_size;
         /* attributes size */
@@ -1491,7 +1426,7 @@ DECL_HANDLER(get_token_groups)
             if (tg)
             {
                 unsigned int *attr_ptr = (unsigned int *)(tg + 1);
-                SID *sid_ptr = (SID *)(attr_ptr + group_count);
+                struct sid *sid = (struct sid *)(attr_ptr + group_count);
 
                 tg->count = group_count;
 
@@ -1506,10 +1441,7 @@ DECL_HANDLER(get_token_groups)
                     if (group->deny_only) *attr_ptr |= SE_GROUP_USE_FOR_DENY_ONLY;
                     if (group->resource) *attr_ptr |= SE_GROUP_RESOURCE;
                     if (group->logon) *attr_ptr |= SE_GROUP_LOGON_ID;
-
-                    memcpy(sid_ptr, &group->sid, security_sid_len( &group->sid ));
-
-                    sid_ptr = (SID *)((char *)sid_ptr + security_sid_len( &group->sid ));
+                    sid = copy_sid( sid, &group->sid );
                     attr_ptr++;
                 }
             }
diff --git a/server/trace.c b/server/trace.c
index 9516435769b..72b404956ec 100644
--- a/server/trace.c
+++ b/server/trace.c
@@ -1016,33 +1016,27 @@ static void dump_varargs_luid_attr( const char *prefix, data_size_t size )
     remove_data( size );
 }
 
-static void dump_inline_sid( const char *prefix, const SID *sid, data_size_t size )
+static void dump_inline_sid( const char *prefix, const struct sid *sid, data_size_t size )
 {
     DWORD i;
 
-    /* security check */
-    if ((FIELD_OFFSET(SID, SubAuthority[0]) > size) ||
-        (FIELD_OFFSET(SID, SubAuthority[sid->SubAuthorityCount]) > size))
+    fprintf( stderr,"%s", prefix );
+    if (sid_valid_size( sid, size ))
     {
-        fprintf( stderr, "<invalid sid>" );
-        return;
+        fprintf( stderr, "S-%u-%u", sid->revision,
+                 ((unsigned int)sid->id_auth[2] << 24) |
+                 ((unsigned int)sid->id_auth[3] << 16) |
+                 ((unsigned int)sid->id_auth[4] << 8) |
+                 ((unsigned int)sid->id_auth[5]) );
+        for (i = 0; i < sid->sub_count; i++) fprintf( stderr, "-%u", sid->sub_auth[i] );
     }
-
-    fprintf( stderr,"%s{", prefix );
-    fprintf( stderr, "S-%u-%u", sid->Revision, MAKELONG(
-        MAKEWORD( sid->IdentifierAuthority.Value[5],
-                  sid->IdentifierAuthority.Value[4] ),
-        MAKEWORD( sid->IdentifierAuthority.Value[3],
-                  sid->IdentifierAuthority.Value[2] ) ) );
-    for (i = 0; i < sid->SubAuthorityCount; i++)
-        fprintf( stderr, "-%u", sid->SubAuthority[i] );
-    fputc( '}', stderr );
+    else fprintf( stderr, "<invalid>" );
 }
 
-static void dump_varargs_SID( const char *prefix, data_size_t size )
+static void dump_varargs_sid( const char *prefix, data_size_t size )
 {
-    const SID *sid = cur_data;
-    dump_inline_sid( prefix, sid, size );
+    const struct sid *sid = cur_data;
+    if (size) dump_inline_sid( prefix, sid, size );
     remove_data( size );
 }
 
@@ -1062,7 +1056,7 @@ static void dump_inline_acl( const char *prefix, const struct acl *acl, data_siz
         size -= sizeof(*acl);
         for (i = 0, ace = ace_first( acl ); i < acl->count; i++, ace = ace_next( ace ))
         {
-            const SID *sid = (const SID *)(ace + 1);
+            const struct sid *sid = (const struct sid *)(ace + 1);
             data_size_t sid_size;
 
             if (size < sizeof(*ace) || size < ace->size) break;
@@ -1104,17 +1098,17 @@ static void dump_inline_security_descriptor( const char *prefix, const struct se
     {
         size_t offset = sizeof(struct security_descriptor);
         fprintf( stderr, "control=%08x", sd->control );
-        if ((sd->owner_len > FIELD_OFFSET(SID, SubAuthority[255])) || (offset + sd->owner_len > size))
+        if ((sd->owner_len > offsetof(struct sid, sub_auth[255])) || (offset + sd->owner_len > size))
             return;
         if (sd->owner_len)
-            dump_inline_sid( ",owner=", (const SID *)((const char *)sd + offset), sd->owner_len );
+            dump_inline_sid( ",owner=", (const struct sid *)((const char *)sd + offset), sd->owner_len );
         else
             fprintf( stderr, ",owner=<not present>" );
         offset += sd->owner_len;
-        if ((sd->group_len > FIELD_OFFSET(SID, SubAuthority[255])) || (offset + sd->group_len > size))
+        if ((sd->group_len > offsetof(struct sid, sub_auth[255])) || (offset + sd->group_len > size))
             return;
         if (sd->group_len)
-            dump_inline_sid( ",group=", (const SID *)((const char *)sd + offset), sd->group_len );
+            dump_inline_sid( ",group=", (const struct sid *)((const char *)sd + offset), sd->group_len );
         else
             fprintf( stderr, ",group=<not present>" );
         offset += sd->group_len;
@@ -1156,16 +1150,14 @@ static void dump_varargs_token_groups( const char *prefix, data_size_t size )
             fputc( '[', stderr );
             for (i = 0; i < tg->count; i++)
             {
-                const SID *sid = (const SID *)((const char *)cur_data + offset);
+                const struct sid *sid = (const struct sid *)((const char *)cur_data + offset);
                 if (i != 0)
                     fputc( ',', stderr );
                 fputc( '{', stderr );
                 fprintf( stderr, "attributes=%08x", attr[i] );
                 dump_inline_sid( ",sid=", sid, size - offset );
-                if ((offset + FIELD_OFFSET(SID, SubAuthority[0]) > size) ||
-                    (offset + FIELD_OFFSET(SID, SubAuthority[sid->SubAuthorityCount]) > size))
-                    break;
-                offset += FIELD_OFFSET(SID, SubAuthority[sid->SubAuthorityCount]);
+                if (!sid_valid_size( sid, size - offset )) break;
+                offset += sid_len( sid );
                 fputc( '}', stderr );
             }
             fputc( ']', stderr );
@@ -3834,7 +3826,7 @@ static void dump_filter_token_request( const struct filter_token_request *req )
     fprintf( stderr, ", flags=%08x", req->flags );
     fprintf( stderr, ", privileges_size=%u", req->privileges_size );
     dump_varargs_luid_attr( ", privileges=", min(cur_size,req->privileges_size) );
-    dump_varargs_SID( ", disable_sids=", cur_size );
+    dump_varargs_sid( ", disable_sids=", cur_size );
 }
 
 static void dump_filter_token_reply( const struct filter_token_reply *req )
@@ -3867,7 +3859,7 @@ static void dump_get_token_sid_request( const struct get_token_sid_request *req
 static void dump_get_token_sid_reply( const struct get_token_sid_reply *req )
 {
     fprintf( stderr, " sid_len=%u", req->sid_len );
-    dump_varargs_SID( ", sid=", cur_size );
+    dump_varargs_sid( ", sid=", cur_size );
 }
 
 static void dump_get_token_groups_request( const struct get_token_groups_request *req )