Secure Communication Paths
As illustrated in the following figure, Drill features five secure communication paths. Drill 1.11 introduces encryption between a Drill client and Drillbit.
- Web Client to Drillbit
- Java and C++ Client to Drillbit
- Java Client and Drillbit to ZooKeeper
- Drillbit to Hive Storage Plugin
Drillbit-to-drillbit encryption is not available yet.
Web Client to Drillbit
The Web UI and REST API clients are web clients. Web clients can:
- Submit and monitor queries
- Configure storage plugins
Impersonation and authorization are available through the web clients only when authentication is enabled. Otherwise, the user identity is unknown.
|Authentication||Users authenticate to a drillbit using a username and password form authenticator. By default, authentication is disabled.||Configuring Web UI and REST API Security|
|Encryption||Drill usese SSL for HTTPS access to the Web UI.||Configuring Web UI and REST API Security|
|Impersonation||Drill acts on behalf of the user on the session. This is usually the connection user (or the user that authenticates). This user can impersonate another user, which is allowed if the connection user is authorized to impersonate the target user based on the inbound impersonation policies (USER role). By default, impersonation is disabled.||Configuring User Impersonation and Configuring Inbound Impersonation|
|Authorization||Queries execute on behalf of the web user. Users and administrators have different navigation bars. Various tabs are shown based on privileges. For example, only administrators can see the Storage tab and create/read/update/delete storage plugin configuration.||Configuring Web UI and REST API Security|
Java and C++ Client to Drillbit
Java (native or JDBC) and C++ (native or ODBC) clients submit queries to Drill. BI tools use the ODBC or JDBC API.
|Authentication||Users authenticate to a drillbit using Kerberos, Plain (username and password through PAM), and Custom authenticator (username and password). By default, user authentication is disabled.||Configuring User Security|
|Encryption||Drill 1.11 supports encryption between a Drill client and a Drillbit with the Kerberos mechanism over a Java SASL framework. Encrypting the client-to-drillbit communication path ensures data integrity and privacy and prevents data tampering and snooping. If encryption is enabled on a drillbit, it will not allow a client without encryption capabilities to connect. By default, encryption is disabled.||Configuring Kerberos Security|
|Impersonation||Drill acts on behalf of the user on the session. This is usually the connection user (or the user that authenticates). This user can impersonate another user. This is allowed if the connection user is authorized to impersonate the target user based on the inbound impersonation policies (USER role). By default, impersonation is disabled.||Configuring User Impersonation and Configuring Inbound Impersonation|
|Authorization||A user can execute queries on data that he/she has access to. Each storage plugin manages the read/write permissions. Users can create views on top of data to provide granular access to that data. The user sets read permissions to appropriate users and/or groups. System-level options can only be changed by administrators (USER role). By default, only the process user is an administrator. This is available if authentication is enabled.||Configuring User Impersonation|
Drill Client and Drillbit to ZooKeeper
Drill clients and drillbits communicate with ZooKeeper to obtain the list of active drillbits. Drillbits store system-level options and running query profiles.
|Authentication||Not fully supported.||Configuring User Security|
|Authorization||Drill does not set ACLs on ZooKeeper nodes (znode).|
|Encryption||Not fully supported.||ZooKeeper SSL User Guide|
Drillbit to Hive Storage Plugin
The planner accesses the Hive Metastore for metadata. During execution, query fragments scan data from Hive using the Hive storage plugin.
|Authentication||Drillbit is a client to the Hive Metastore. Authentication options include Kerberos and DIGEST. By default, authentication is disabled.||Kerberos (if Hive impersonation is disabled and Kerberos principal is mentioned) and DIGEST (the only supported mechanism when Hive impersonation is enabled and SASL is enabled).|
|Impersonation||While accessing Hive Metastore, Hive impersonation setting in the storage plugin configuration overrides Drill’s impersonation setting. While scanning data in Hive, Drill impersonation is applied.||Configuring User Impersonation|
|Authorization||Drill supports SQL standard-based authorization and storage-based authorization.||Configuring User Impersonation with Hive Authorization|