Access Control Enterprise

Dremio allows for the implementation of granular-level privileges, which defines a user/role’s access privilege and available actions for specific objects, such as folders and datasets. This is called access management, and gives administrators the ability to restrict access to any object in Dremio.

Based on the inheritance model, when a user is granted privileges to an object with child objects, the user's privilege also applies to the child objects. This is also known as scope, meaning the specific objects to which a privilege applies.

Access to objects is granted via privileges assigned to users or groups.

The following features are available:

• Privileges: Privileges enable users to perform explicit operations on objects in Dremio. Additionally, privileges may be set on individual datasets (tables or views) or whole schemas, allowing for a simplified configuration with larger catalogs.
• Row-access and column-masking policies: Row-access and column-masking policies enable you to grant users access to particular rows or columns.
• Flexible Management: Privileges can be easily configured using SQL Commands, REST APIs, and an intuitive and easy-to-use user interface.
• Ownership: An object-oriented model allows for a clearly-defined and transferable owner for all aspects in Dremio, including source and space configuration.
• Roles: Administrators may create and manage identities in Dremio alongside identities from corporate LDAP or IdP, including standards-based synchronization (SCIM).

The following topics cover the various aspects of access management, along with instructions for how to apply privileges via Dremio:

• Best Practices
• Privileges
• Role Management
• Inbound Impersonation
• Integrating with AWS Lake Formation
• Integrating with Privacera
• Apache Ranger: Row-Level Filtering & Column-Masking
• Dremio-Native: Row-Access & Column-Masking Policies

The following APIs are available for managing access control:

• Grants APIs
• Privileges APIs
• Roles APIs
• Users APIs

The following SQL commands may be used from the SQL Runner:

• Privileges SQL Commands
• Roles SQL Commands
• Users SQL Commands

Object Hierarchy

Each object resides within a container in a hierarchy of containers. The upper-most container exists as the system user, or administrator account. All other objects are contained within sources or spaces, organized into folders. The hierarchy of these objects is illustrated below.

Inheritance

The objects to which privileges are granted depend on the inheritance model. In other words, granting access to a parent object, such as a folder, also gives that user access to any existing and future datasets contained in that folder. For example, giving a user privileges to ALL DATASETS will only grant the user access to existing datasets, not the folders that contain the datasets. In comparison, granting privileges at the source level will extend that user's access to the source's existing and future folders/schema and datasets. The object to which a user's privileges are applied is also known as the scope, and follow a parent-child relationship.

By the rules of inheritance, user or group access may be granted as high or low in the object hierarchy as you wish for access to reach.

Permissions granted to an individual table or view mean that a user's access only extends to that dataset, not to the parent folder or other datasets created in the same folder. So if a user only needs access to a single dataset, administrators need only grant privileges to that object.

Consider the image above, which shows an example of object structure in Dremio. If a user is granted privileges to a single dataset, such as TableA1, then that is the one object they have access to. However, if a user is granted privileges at the folder level, such as Folder1, then that user's access extends to any existing and future child objects created, including FolderA, TableA1, TableB1, and so on.

note

If a user has privileges for a single table, they may create views based on that dataset, but with the user now having ALTER and MANAGE GRANTS privileges for any view. However, the user still retains the same privileges as before with the original dataset. For more information, read View Delegation.

Scope

Scope is a concept used to describe what objects a user or group has access to. Privileges are assigned by object, which ultimately determines what a grantee may perform set functions upon. For example, you may set a user's scope to FolderA, which will give the user access to all existing and future datasets contained in the folder, as well as the datasets' wikis. But they will not have access to any other folders or the source. The object a user is granted access to is dependent on the inheritance model, which means based on the object type, it may contain child objects. For example, if a user is granted privilege to a folder, the user's access also extends to all existing and future datasets contained in that folder.

For example, user1 is granted the SELECT privilege to the folder FolderC. This object contains multiple datasets, which the user may now access. However, there exists a parent folder and another subfolder with its own datasets.

Because of the established scope, user1 may not access FolderD because they were only granted access to FolderC's objects.

Current vs. Future Objects

Based on the selected scope, you may restrict a user's access to future and existing datasets. For example, if you select a single table as the scope of a user's privilege, then that user may only perform that action to the existing dataset, as well as any future views they create using that table. However, they may not access any views created from a table by another user (see the example below). However, if the scope is instead set at the folder level, then the user may perform the granted privilege to all tables and views contained in that folder (see the example below).

Ownership

Object ownership is a security feature used to control access to an object as well as oversee who has that control. In Dremio, each object MUST have an owner, and may have only one owner. Ownership is automatically granted to the user who initially creates the object. For example, if User1 creates an S3 data source, Dremio automatically assigns ownership of the source to User1.

The implication of ownership is that only an object's owner retains all privileges for that object. As a result, the owner can grant or revoke user and role access to that object and its child objects, modify the object's settings, and drop or delete the object as desired. Read View Delegation and Granting Privileges Using SQL Commands for examples and more information.

The following behaviors and limitations apply to ownership:

• Each object may only have one owner.
• An object's creator is automatically granted ownership.
• Object owners must have the USAGE privilege on the system, source, or folder that contains the object to query or grant and revoke other privileges on the object.
• Object ownership may be assigned or modified with GRANT TO USER or GRANT TO ROLE commands.
• If an owner is deleted or removed, the object's access control settings may not work.
• Object owners may be identified by querying sys."tables" or sys.views for views.
  • If an object has no owner, the owner_id will display as $unowned.

For datasets with no owner, the system user (administrative account) can use the GRANT SQL command to grant ownership to a user or role that has access to the table (or the underlying table, for a view).

View Delegation

View delegation means that tables with restricted access may be shared with other Dremio users through the creation of views. When a user with SELECT access to a table creates a view, that user automatically becomes owner of the new object.

Upon creating the view, the same rules of ownership apply to the view. The owner or delegation identity does not change when a view is edited or queried, but must be manually changed via the GRANT TO USER or GRANT TO ROLE commands. To identify the owner of a view, query the sys.views table.

note

The shared view still selects from the underlying dataset using the view owner's permissions at the time of the view's last modification, even if the end user querying the view lacks privileges to modify the underlying table. This applies to each table on the data graph and chain of datasets.

View delegation is different from privilege assignment. View delegation is implicit delegation of the SELECT privilege on underlying objects. For example, suppose user1 has the SELECT privilege on Table1 and creates View1 based on Table1. If user1 grants the SELECT privilege on View1 to user2, then the SELECT privilege that user1 has on Table1 is implicitly granted to user2. user2 can see the data in Table1 even though they lack explicit SELECT privileges on Table1. Privilege assignment is an explicit delegation: the owner of an object or a user who belongs to the ADMIN role grants privileges on the object to other users.

Example: View Delegation

user1 has SELECT access to Table1 and creates View1, which is based upon Table1. Whereas in Table1, user1 was restricted to only querying, with View1, they now have ALTER and MANAGE GRANTS privileges. user1 may now grant user2 with the SELECT privilege for View1 because of view delegation. The privileges for both the table and view are outlined below:

	View1	Table1
user1	ALTER, MANAGE GRANTS	SELECT
user2	SELECT	No access

user2 previously lacked access to the data in Table1 but may now see it using SELECT queries on View1. The following table describes the actions that each user may perform:

User	Action	Outcome
user1	View the results of View1 queries	yes
user1	Modify the original query of View1	yes
user2	View the results of View1 queries	yes
user2	Modify the original query of View1	no

Because of view delegation, user2 can view the data in Table1 through the results of queries on View1. However, user2 has no access to Table1, so they cannot see the original dataset from the Dremio interface and cannot modify the original View1 query.

Example: View Delegation with Revoked Access to the Original Table

To continue the previous example, suppose user1 originally had SELECT access to Table1, which they used to create View1. If an administrator revokes their SELECT access to Table1, the following table lists the privileges that user1 and user2 now have on Table1 and View1:

	View1	Table1
user1	ALTER, MANAGE GRANTS	No access
user2	SELECT	No access

The revoked privilege affects the actions that user1 can take with regard to View1. The following table describes what actions each user may now perform:

User	Action	Outcome
user1	View the results of View1 queries	no
user1	Modify the original query of View1	yes (and no)
user2	View the results of View1 queries	no
user2	Modify the original query of View1	no

user1 and user2 may no longer view the results of the View1 query. Both users lack privileges for the underlying table Table1, so neither can see data from the table or view from the Dremio interface. Also, user1 can no longer modify the original View1 query unless they remove the reference to Table1 from it. If user1 attempts to modify the query but does not remove the reference, they will not be able to save the modified query.

Example: View Delegation with Original Query Changed and Revoked Access

In this example, both user1 and user2 have ALTER and MANAGE GRANTS privileges for Table1 and View1 created from it, as shown in the following table:

	View1	Table1
user1	ALTER, MANAGE GRANTS	SELECT
user2	ALTER, MANAGE GRANTS	SELECT

Suppose an administrator then revokes access to both Table1 and View1 from user2. If user2 modified and saved View1 before their privileges were revoked, subsequent queries would be executed as user2. After the privileges of user2 are revoked, subsequent queries performed by user1 would display an error message about lacking sufficient privileges. This is because View1 was last altered by user2, making user2 the owner of View1.

user2 can no longer see Table1 or query either View1 or Table1 from the Dremio interface. user1 can see only the last definition of View1 that user2 saved. user1 must modify the last definition of View1 to retain ownership and resume viewing query results.

Privileges

Privileges refer to the defined levels of access or permissions that are assigned to roles or users within Dremio. Privileges determine the operations a user or role can perform on securable objects. Examples of privileges in Dremio include SELECT on a table or view, INSERT on a table, DELETE on a table, CREATE TABLE on a folder, and MANAGE GRANTS on any object.

The assignment of privileges to roles, or users, should be based on the principle of least privilege, where users or roles are given only the minimum privileges required to perform their tasks effectively.

Privileges can be managed using SQL, APIs, or the Dremio Console.

For more information, please refer to Privileges.

Granting Privileges Using the Dremio Console

You can share catalog objects with others in your organization by granting privileges on the objects to users and roles as follows:

1. Locate the desired object.

2. Click or depending on the object.

3. In the object settings dialog, select Privileges from the settings sidebar.

note

For some object types, the settings dialog automatically opens to display the privilege settings, and you do not need to select the Privileges tab.

4. In the Privileges dialog, in the field under Add User/Role, enter the exact names of the users and roles to which you want to grant privileges.

note

Because all users are members of the PUBLIC role, you can use the PUBLIC role to grant privileges to all users.

5. Click Add to Privileges.

For each entry in the Add User/Role field that matches a user or role in Dremio, a record appears in the USERS/ROLES table.

6. In the USERS/ROLES table, toggle the checkbox for each privilege you want to grant for that user or role. For a description of the privilege, hover over the column name in the USERS/ROLES table. See the example below:

   

7. (Optional) Repeat steps 4-6 if you want to add more users or roles and grant them privileges.

8. When finished, click Save.

Revoking Privileges Using the Dremio Console

To revoke user and role privileges, complete the following steps:

1. Locate the desired object.

2. Click or depending on the object.

3. In the object settings dialog, select Privileges from the settings sidebar.

   note

   For some object types, the settings dialog automatically opens to display the privilege settings, and you do not need to select the Privileges tab.

4. In the USERS/ROLES table, locate the desired user or role record. If the user or role is not listed, then they do not have specific privileges on the object.

   • To revoke some but not all privileges for the user or role, clear the checkboxes in the columns for the privileges you wish to revoke.

   • To revoke all privileges for a user or role, click next to the user or role name and select Remove.

   For a description of the privilege, hover over the column name in the USERS/ROLES table. See the example below:

5. When finished, click Save.

note

If a user has a specific privilege on an object through their memberships in multiple roles and the privilege is revoked for one of the roles, the user retains the privilege until it is revoked on the same object for all roles to which the user belongs.

tip

You can also grant or revoke privileges using SQL commands or APIs.

Granting Privileges Using SQL Commands

When granting privileges to users and roles with SQL commands, you may follow one of three methods: granting to a single dataset, granting to ALL DATASETS, and granting to a scope. Examples of these methods may be found under each section.

Each example includes an SQL command. For more information about command syntax, review the Privileges (GRANT/REVOKE) SQL commands.

note

Because all users are members of the PUBLIC role, you can use the PUBLIC role to grant privileges to all users.

Granting to a Single Dataset

When you have a user that needs access to only one table and no other objects, then you would simply assign them privileges for that dataset (see the example scenario outlined below).

You should use this method if you want to restrict a user's access to any other existing or future datasets.

note

If you're granting the user access to a table, then remember that they'll be able to create views based on that dataset, which that user can then grant access to other users.

Example: Single Dataset

You have a user that you only want to give access to an individual table. You would need to navigate to the Privileges screen from that dataset's settings and grant the user the SELECT privilege, or perform the following command from the SQL Editor:

Single dataset example

GRANT SELECT ON TABLE TableA1 TO USER user1

The image below illustrates the objects user1 now has access to.

This restricts user1 so that they may only access the TableA1 table, not any other datasets contained in the same folder. However, user1 may still create views based on TableA1.

Granting to ALL DATASETS

When you have a user that needs access to all existing datasets, then you would use the SQL syntax ON ALL DATASETS (see the example scenario outlined below). This gives the user access to all existing datasets. The user would not, however, automatically receive access to any future datasets created by other users.

You should use this method of privilege assignment if you want to restrict a user's access to parent objects, but still wish for them to have access to all existing datasets.

Example: All Datasets

You have a specific user that needs access to all datasets in a specific folder, but they do not require privileges for the folders containing these tables. You would then execute the following command from the SQL Editor:

All datasets example

GRANT SELECT ON ALL DATASETS IN SYSTEM TO USER user1

The image below illustrates the objects user1 now has access to.

This command restricts the scope of user1 to all datasets presently found in source1, such as TableC1 and TableD1. Should additional datasets be created in the future, user1 will not have access to them.

Granting to a Scope

When you want to grant a user access to a parent object, such as a folder, this will also grant the user access to any datasets contained (see the example scenario outlined below).

You should use this method of privilege management if you wanted to grant a user access to all existing and future datasets contained under a parent object.

Example: Scope

This method grants a user access to all existing and future datasets contained under a specified object. To accomplish this, you need to navigate to the Privileges screen from that folder's settings and grant the user the SELECT privilege, or execute the following command from the SQL Editor:

Scope example

GRANT SELECT ON FOLDER Folder3 TO USER user1

The image below illustrates the objects user1 now has access to.

This grants user1 the SELECT privilege on Folder3, which means they now have access to all existing and future datasets contained in that folder and its subfolders.