Bug#20570: CURRENT_USER() in a VIEW with SQL SECURITY DEFINER returns

           invoker name

The bug was fixed similar to how context switch is handled in
Item_func_sp::execute_impl(): we store pointer to current
Name_resolution_context in Item_func_current_user class, and use
its Security_context in Item_func_current_user::fix_fields().


mysql-test/r/view_grant.result:
  Add result for bug#20570.
mysql-test/t/view_grant.test:
  Add test case for bug#20570.
sql/item_create.cc:
  Remove create_func_current_user(), as it is not used for automatic
  function creation.
sql/item_create.h:
  Remove prototype for create_func_current_user().
sql/item_strfunc.cc:
  Add implementations for Item_func_user::init(),
  Item_func_user::fix_fields() and
  Item_func_current_user::fix_fields() methods.  The latter uses
  Security_context from current Name_resolution_context, if one is
  defined.
sql/item_strfunc.h:
  Move implementation of CURRENT_USER() out of Item_func_user to
  to new Item_func_current_user class.  For both classes calculate
  user name in fix_fields() method.
  For Item_func_current_user add context field to store
  Name_resolution_context in effect.
sql/sql_yacc.yy:
  Pass current Name_resolution_context to Item_func_current_user.

1 files changed, 0 insertions, 1 deletions

diff --git a/sql/item_create.h b/sql/item_create.h
index 35db9be3c89..cf61f90f91d 100644
--- a/sql/item_create.h
+++ b/sql/item_create.h
@@ -73,7 +73,6 @@ Item *create_func_period_add(Item* a, Item *b);
 Item *create_func_period_diff(Item* a, Item *b);
 Item *create_func_pi(void);
 Item *create_func_pow(Item* a, Item *b);
-Item *create_func_current_user(void);
 Item *create_func_radians(Item *a);
 Item *create_func_release_lock(Item* a);
 Item *create_func_repeat(Item* a, Item *b);