Users authorization settings and authentication access rules

UAC Policies

Manage users’ access to TimeBase streams via User Access Control (UAC):

UAC Rules

In order to implement UAC policies, system administrator defines a set of UAC rules. Each UAC rule tells the system who can perform what action and on which resources (streams). For example, “user John can read stream level2data”. UAC rules define Actors, Actions and Targets:

  • Actor - user or a group of users who can perform a specific action
  • Action - action or permission (e.g. reading a TimeBase stream). There is a set of predefined actions that can be extended.
  • Target - describes thr resource the rule applies to. There are two types of targets:
    • Stream
    • User or a Group. In this case rule applies to all resources owned by a given user or group.

UAC rules can be defined in any order. Each rule may contain multiple actors, actions, and/or targets. Please do not confuse groups and their permissions. Groups define administrative structure of your organization. UAC Rules define what each group (or an individual user) is allowed to do. Typically, groups are used to model various roles in the organization. For example, custom group TimeBaseDesigners may provide permissions to create new TimeBase streams.

Example

The following rule allows user admin to modify TimeBase stream called Securities and read any stream that belongs to one of the members of Traders group

  Actor Action Target
Allow admin (user) READ,WRITE Securities (stream)
Allow admin READ Traders (group)

Wildcards

System allows defining UAC rules that apply to any target or provide any permission to a given actor. In case wildcard character * appears in the context of an Actor, it means anybody. In case wildcard character * appears in the context of an Action it means any action. Similarly, * in the context of a Target means any person or any resource.

Example

The following rule allows members of Administrators group to do anything:

  Actor Action Target
Allow Administrators (group) * *

The following rule allows members of group GoodTraders to share everything. This rule literally means: allow any member of a group GroupTraders to perform any action on any resource (stream) that belongs to any member of this group.

  Actor Action Target
Allow GoodTraders (group) * GoodTraders (group)

Resource Patterns

Target can use simple patterns to identify resources and users. In addition to simple wildcards described in the previous section, a target can use

  • Multiple wildcards:

      Actor Action Target (format:wildcard)
    Allow GoodTraders (group) * *Futures* (stream pattern) any stream that contains word FUTURES in its name
  • Regular Expression (There are many syntax references):

      Actor Action Target (format:regex)
    Allow GoodTraders (group) * .+Futures.+ (stream pattern) any stream that contains word FUTURES in its name

Resource Ownership

TimeBase streams are resources for UAC. Each stream has a single owner (usually user who created this specific stream/resource). System automatically defines only once implicit permission for resource owners to perform any action on owned resources.

  Actor Action Target
Allow John * John

System Rules

System rules describe actions over resources that does not belong to specific user or belong to unknown user. For example, the following rule allows any user group member to create TimeBase streams. You can omit the Target argument for system rules.

  Actor Action
Allow Use Group CREATE

Orphan Resources

Resources owned by unknown users (e.g. users that have been removed from the Directory Service) de-facto belong to the system, but require system rules.

Deny Rules

It is possible to express security policy in terms like “allow anything except…”. This can be implemented using a combination of Allow and Deny rules. For example, to allow user John editing any stream except “securities”:

  Actor Action Target
Allow John (user) READ,WRITE * (stream)
Deny John (user) WRITE securities (stream)

Just like Allow rules, rules that have Deny effect can use * action, as well as wildcards and regular expressions, and use any resource type as target. Order in which different rules are defined is not important. Each permissions check is done in two steps:

  1. Reject action if user doesn’t have matching Allow rule, otherwise go to Step 2.
  2. Reject action if user has matching Deny rule, otherwise allow the action.

Multiple Groups Membership

User inherits permissions of all groups the user is a member of.

Consider the following example:

User John is a member of groups: TimeBaseConsumers and TimeBaseProducers. In our example permissions are defined in following way:

  Actor Action Target
Allow TimeBaseConsumers READ * (stream)
Allow TimeBaseProducers CREATE, READ, WRITE * (stream)

As a member of each of these groups John will have all these permissions:

  Actor Action Target
Allow John CREATE, READ, WRITE * (stream)

Membership in groups that have Deny access rules may reduce user rights. For example, if TimeBaseConsumers are not allowed to edit ‘securities’ stream, John won’t be able to edit this stream despite the fact that TimeBaseProducers can edit any stream.

  Actor Action Target
Deny TimeBaseConsumers WRITE * (stream)

User Impersonation

System allows administrative users to impersonate other users. For example, Administrator may be allowed to create a stream that belongs to a specific user. This action is controlled using IMPERSONATE permission. System performs two checks every time resource changes ownership:

  1. Current User, IMPERSONATE, New Owner
  2. Current User, IMPERSONATE, Old Owner

Permission IMPERSONATE can only be defined using principal (user or group) as permission targets.

Predefined Permissions

The following table lists TimeBase permissions.

Action Description System Resource
READ Permission to read a stream   +
WRITE Permission to write into a stream. User must also have READ permission on the stream.   +
CREATE System permission to create a stream +  
CHANGE_SCHEMA Administrative permission to edit stream schema (data types). User must also have WRITE permission to commit changes.   +
IMPERSONATE Administrative permission to impersonate other users. Typically is granted to Administrators who create streams and grant access to TimeBase on behalf of other, non-administrative users. This permission allows users to change stream ownership (define a user who owns a stream). Internal use only.   +

Rules Definition

TimeBase UAC rules are defined in uac-access-rules.xml file located in <TimeBase Home>/config folder.

The following table briefly describes uac-access-rules.xml file format:

XML Element XML attribute Description Examples
allow   Contains ALLOW rule  
deny   Contains DENY rule  
principal   Actor - user or group that identifies who will be performing allowed action John Administrators
permission   Action - one of standard or custom permission names. Can be * (any). READ, *
resource   Identifies resource (user, group, or stream) . Can be * (any) securities Traders
resource Type One of: “Stream” or “Principal”. Optional. Default is “Principal”. type=”Stream”
resource Format One of: “Text”, “Wildcard” or “RegEx”. Optional. Default is “Text”. format=”RegEx”
<!-- `uac-access-rules.xml` example -->

<!-- Any member of Users group can READ "data" stream -->

<allow>
	<principal>Users</principal>
	<permission>READ</permission>
	<resource type="Stream">data</resource>
</allow>
<!-- Note that each rule may contain multiple principal, permissions, and resources:-->
<allow>
	<principal>Users</principal>
	<permission>CREATE</permission>
</allow>
<allow>
	<principal>Users</principal>
	<permission>READ</permission>
	<resource type="Stream">data</resource>
	<resource type="Stream">securities</resource>
	<resource type="Stream">events#</resource>
	<resource type="Stream" format="Wildcard">ES#SYS#*</resource>
</allow>
<deny>
	<principal>trader1</principal>
	<permission>WRITE</permission>
	<resource type="Stream">securities</resource>
</deny>

UAC Configuration

Authentication Provider Configuration

TimeBase uses Apache Directory Service and Active Directory as authentication service providers via LDAP.

You can configure TimeBase to read Users/Groups either from Apache Directory Server and Active Directory or from the local file uac-file-security.xml located in /config folder.

UAC Configuration via LDAP

LDAP configuration file can be generated by UACCONF tool. You can also find a sample of this file in \build\classes\config\uac-ldap-security.xml. This file defines LDAP connection parameters (host, port, login credentials) and query filters that locate user groups for TimeBase. You can customize these queries and define multiple group filters. For example, the following filters locate custom group TimeBaseUsers:

  • Apache DS:

      <groups filter="(&(objectClass=groupOfUniqueNames)(cn=TimeBaseUsers))" node="ou=ExternalGroups,dc=timebase,dc=com"/>
    
  • MS Active Directory:

      <groups filter="(&(objectClass=group)(cn=TimeBaseUsers))" node="ou=ExternalGroups,dc=timebase,dc=com"/>
    

Set the following admin.properties (located in <TimeBase Home>/config) to configure LDAP:

QuantServer.security=LDAP
QuantServer.security.rulesConfig=uac-access-rules.xml
QuantServer.security.userDirectoryConfig=uac-ldap-security.xml

When your users directory is stored in LDAP you need to tell TimeBase which group(s) are allowed to access TimeBase. TimeBase system will build the list of users based on these groups. Every TimeBase user must be a member of at least one group listed in the LDAP configuration. Groups and users excluded from this list will not be allowed to access the system (such users will not be authenticated).

This approach is recommended for large organizations that have a lot of users and their entire organizational structure is defined in services like Active Directory and do not want to expose all users to TimeBase.

Directory service implementations like Apache DS lack convenient and simple GUI to create users and groups. To simplify the procedure, TimeBase provides UAC Shell that simplifies this task. You can also define your user directory in Apache Directory Studio GUI.

UAC Configuration via XML File

You can define users and groups in uac-file-security.xml located in TimeBase Home>/config folder.


<!-- uac-file-security.xml example -->

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<config xmlns="http://xml.deltixlab.com/internal/quantserver/3.0">
    <users>
        <user id="admin">
            <password>admin</password>
        </user>
        <user id="JohnDoe">
            <password>QWERTY</password>
        </user>
        <user id="OwnersManager">
            <password>123</password>
        </user>
        <user id="User1">
            <password>123</password>
        </user>
        <user id="User2">
            <password>123</password>
        </user>
        <user id="User3">
            <password>123</password>
        </user>
        <user id="User4">
            <password>123</password>
        </user>
    </users>
    <groups>
        <group id="Administrators">
            <principal>admin</principal>
        </group>
        <group id="Users">
            <principal>JohnDoe</principal>
        </group>
    </groups>
</config>

Set the following admin.properties (located in <TimeBase Home>/config) to configure UAC via XML file:

QuantServer.security=FILE
QuantServer.security.rulesConfig=uac-access-rules.xml
QuantServer.security.userDirectoryConfig=uac-file-security.xml

UAC Rules Configuration

TimeBase stores UAC Rules in uac-access-rules.xml file under Home/Config folder. File syntax is explained in the Rules Definition section. With well-defined roles mapped to custom groups this file can be configured just once. Day to day tasks like adding new users, are usually implemented using group membership rather than editing access rules. Refer to Best Practices to learn more.

UAC Tools

UACCONF

TimeBase provides special utility that prepares LDAP configuration for future use. It does the following:

  1. Generates configuration file that describes LDAP UAC configuration for TimeBase. This file is stored in Home\config\uac-ldap-security.xml.
  2. When running against Apache DS, the tool pre-creates users, groups, and rules. This is useful for installations that use clean directory service. If you already have your organization defined in one of the directory services, skip this step.

The following example shows tool arguments. Note, that we use full username to connect to LDAP. Also this sample uses domain "dc=timebase,dc=com" (in your case it might be a different one).

uacconf -home "C:\temp\home" \ 
        -server ldap://localhost:10389 \ 
        -user "uid=admin,ou=system" 
        -pass secret \ 
        -domain "dc=timebase,dc=com"

Shell

TimeBase provides command line utility (located at \bin\uac) you can use to edit users and groups in Apache DS (or any LDAP). If you use Microsoft Active Directory we recommend using Microsoft GUI to manage user directory. The following example shows how use UAC tool.

For a complete list of commands supported by UAC type help or ?.

You can exit this tool using exit or quit commands

First of all, this tool needs to know the location of your TimeBase Home directory. There are two ways to supply this information:

  • specify this via command line argument -home
  • set home variable after you launch the tool:
Connect
==> set home .../Home 
Setting home=.../Home 
==> connect 
... 
==> list 
>>> Directory Users: 
Admin Admin, Member Of: (Administrators), Description: jdoe John Doe, Member Of: (Traders), Description: 
>>> Directory Groups: 
Traders Users: (jdoe), Groups: () Administrators Users: (Admin), Groups: () ...
Add User

The following example shows how to connect to Directory Server:

==> newuser jsmith;password;Traders;Jeff;Smith;This is a description 
==> list 
>>> Directory Users: 
Admin Admin, Member Of: (Administrators), Description: jdoe John Doe, Member Of: (Traders), Description: jsmith Jeff Smith, Member Of: (Traders), Description: 
>>> Directory Groups:
Traders Users: (jdoe,jsmith), Groups: () Administrators Users: (Admin), Groups: () ... 
==>quit
Add Group

The following sample shows how to add a group “RiskManagers” that consist of two members (andy, and nick):

==> newgroup RiskManagers;andy,nick 
==> listgroups 
>>> Directory Groups: 
Risk Users: (nick, andy), Groups: () 
...

Best Practices

Minimize UAC Rules

TimeBase UAC uses “default-deny” model - by default everything is prohibited. UAC rules that you define should allow users to perform their normal tasks but not much more.

Minimize Users that Can Access TimeBase

We recommend limiting users that may use TimeBase software using group filters in LDAP configuration. For example, you can create a group Users end list eligible users in this group (a group can reference other groups). Limiting group filter to Users ensures that anybody who is not a member of this group will not be able to pass authentication (and gain any access to the system).

<groups filter="(objectClass=groupOfUniqueNames)" node="ou=DeltixUsers,ou=groups,dc=deltix,dc=com"/>

To allow multiple groups you can specify multiple group elements in your LDAP configuration file.

Role-Based Groups

Define custom groups that reflect different roles people play in your organization. A user can be a member of more than one group. We recommend using groups rather than individual rules for users.

Avoid Too Many DENY Permissions

By default, system prohibits everything, but the best way to prohibit something is minimizing UAC rules rather than granting too many permissions. For example, if you want to prohibit access to a resource for a specific user, simply exclude this user from a group rather than defining another DENY rule for this user.