KingbaseES 数据库中不同user的视图访问授权

前言

本文的目的是实现u1用户访问ud用户下的视图权限。

测试

登录system用户并创建schema，user，并授权schema的有关权限给ud用户
TEST=# select current_user;
 current_user
--------------
 system
(1 row)
TEST=# create schema ud;
CREATE SCHEMA
TEST=#
TEST=# create user ud;
CREATE ROLE

TEST=# grant usage on schema ud to ud;
GRANT
TEST=#
TEST=# grant select ON ALL TABLES IN SCHEMA ud to ud;
GRANT
TEST=# grant create on schema ud to ud;
GRANT

登录ud用户并执行命令
TEST=# \c - ud
You are now connected to database "TEST" as user "ud".
TEST=> create table ti (id int);
CREATE TABLE
TEST=> insert into ti values(1);
INSERT 0 1
TEST=>
TEST=> select * from ti;
 id
----
  1
(1 row)
TEST=> create  view view_tu as select * from ti;
CREATE VIEW
TEST=>
TEST=> select * from view_tu;
 id
----
  1
(1 row)

登录system用户，创建role01并把视图的查询权限赋给role01
TEST=> \c - system
You are now connected to database "TEST" as user "system".
TEST=#
TEST=#
TEST=# create role role01;
CREATE ROLE
TEST=# grant select on ud.view_tu to role01;
GRANT

把role01角色赋给u1用户
TEST=# grant role01 to u1;
GRANT ROLE
TEST=#
TEST=# \du
                                    List of roles
 Role name |                         Attributes                         | Member of
-----------+------------------------------------------------------------+------------
 ab        |                                                            | {ceshi001}
 ceshi001  | Cannot login                                               | {}
 manager   | Cannot login                                               | {}
 role01    | Cannot login                                               | {}
 sao       | No inheritance                                             | {}
 sso       | No inheritance                                             | {}
 system    | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
 u1        |                                                            | {role01}
 ud        |                                                            | {role01}

登录u1用户，查询schema ud下的视图，报错权限不足
TEST=# \c - u1;
You are now connected to database "TEST" as user "u1".
TEST=>
TEST=> select * from ud.view_tu;
ERROR:  permission denied for schema ud
LINE 1: select * from ud.view_tu;
                      ^

登录system用户并把schema ud 的权限赋给u1

TEST=> \c - system
You are now connected to database "TEST" as user "system".
TEST=#
TEST=#
TEST=# grant all privileges on schema ud to u1;
GRANT
TEST=#
登录u1用户，授权后可以查询schema ud的视图
TEST=# \c - u1
You are now connected to database "TEST" as user "u1".
TEST=>
TEST=> select * from ud.view_tu;
 id
----
  1
(1 row)

总结

如下，我们看到角色role01有视图view_tu的查询权限
                             Access privileges
 Schema |  Name   | Type | Access privileges | Column privileges | Policies
--------+---------+------+-------------------+-------------------+----------
 ud     | view_tu | view | ud=arwdDxt/ud    +|                   |
        |         |      | role01=r/ud       |                   |
(1 row)

如下，我们看到u1用户拥有角色role01的权限
TEST=> \du
                                    List of roles
 Role name |                         Attributes                         | Member of
-----------+------------------------------------------------------------+------------
 ab        |                                                            | {ceshi001}
 ceshi001  | Cannot login                                               | {}
 manager   | Cannot login                                               | {}
 role01    | Cannot login                                               | {}
 sao       | No inheritance                                             | {}
 sso       | No inheritance                                             | {}
 system    | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
 u1        |                                                            | {role01}
 ud        |                                                            | {role01}

因为前面执行过一个授权语句：grant all privileges on schema ud to u1;
根据以下sql查询权限得知u1拥有了在schema ud的USAGE和CREATE权限
select a.nspname,b.rolname,string_agg(a.pri_t,',') from
(select nspname,(aclexplode(COALESCE(nspacl, acldefault('n'::"char",nspowner)))).grantee as grantee,
(aclexplode(COALESCE(nspacl, acldefault('n'::"char",nspowner)))).privilege_type as pri_t
from pg_namespace where nspname not like 'pg%' and nspname <> 'information_schema') a,pg_authid b
where (a.grantee=b.oid or a.grantee=0) and b.rolname='u1' group by a.nspname,b.rolname;
   nspname   | rolname |  string_agg
-------------+---------+--------------
 public      | u1      | USAGE,CREATE
 sys         | u1      | USAGE
 sys_catalog | u1      | USAGE
 sysaudit    | u1      | USAGE,CREATE
 sysmac      | u1      | USAGE
 ud          | u1      | USAGE,CREATE
(6 rows)

经过以上的授权步骤我们可以看出，如果要实现u1用户对ud用户下视图的查询权限需要经过一些列复杂的授权过程。
尤其需要注意u1对schema ud的有关权限，否则即使拥有角色role01的查询权限也无法查看其他schema下视图。