WebSphere® Application Server supports
two policy set caller binding configuration options to establish client
security context using SAML security tokens in web services SOAP request
messages. The two configuration options are mapping SAML tokens to
a user entry in a local user repository and, asserting SAML tokens
based on a trust relationship.
Before you begin
This task assumes that you are familiar with WebSphere Application Server SAML technology.
About this task
This task describes setting the WebSphere Application Server policy set caller
binding configuration option to establish client security context
using SAML security tokens in web services SOAP request messages.
You can either map SAML tokens to a user entry in a local user repository
or assert SAML tokens based on a trust relationship. The second configuration
option does not require accessing the local user repository. Instead,
the WS-Security runtime environment populates the client security
context entirely using the contents of SAML security tokens. This
process is based on a trust relationship to the SAML token issuer.
If a SAML tokens specifies the sender-vouches subject confirmation
method. the process is based on a trust relationship to the message
sender.
Procedure
- Configure a policy set caller binding and select the SAML
token type to represent a web services client request.
- Click .
- Click New to create the caller
configuration.
- Specify a Name, such as caller.
- Enter a value for the Caller identity local
part. For example, http://docs.oasis-open.org/wss/oasis-wss-saml-token-profile-1.1#SAMLV2.0,
which must match the local part of the
CustomToken
element
in the attached WS-Security policy.
- Click Apply and Save.
- Optional: Map SAML security tokens to a user
entry in a local user repository.
Mapping to a user entry
is the default behavior when you configure a caller binding without
specifying a configuration option. Alternatively and optionally, you
can select this configuration option explicitly using the following
steps:
- On the caller binding configuration page, add a Callback
handler:
com.ibm.websphere.wssecurity.callbackhandler.SAMLIdAssertionCallbackHandler
.
- Add a Callback handler custom property,
crossDomainIdAssertion
,
and set its value to false.
- Optional: Assert SAML security tokens based
on trust relationship.
- On the caller binding configuration page, add a Callback
handler:
com.ibm.websphere.wssecurity.callbackhandler.SAMLIdAssertionCallbackHandler
.
- Add a Callback handler custom property,
crossDomainIdAssertion
,
and set its value to true.
In
WebSphere Application Server Version
7.0 Fix Pack 7 and later releases, the WS-Security runtime environment
takes a SAML token Issuer name to represent the foreign security realm
name. WS-Security takes the
NameID
element in the
case of SAML 2.0 security tokens or the
NameIdentifier
element
in the case of SAML 1.1 security tokens to represent user security
name. Alternatively, you can explicitly specify which SAML token attribute
to use to represent user security name. Moreover, you can also specify
which SAML token attribute to use to represent user group membership.
Read about SAML assertions across
WebSphere Application Server security domains
for a detailed discussion of the SAML token assertion trust model
and binding configuration.
Version 8.x can propagate the contents
of com.ibm.websphere.security.cred.WSCredential
in
a SAML token. You must set a tokenRequest
custom
property with an issueByWSCredential
property value
in the WS-Security binding configuration of the web services client.
Read about propagating SAML tokens for a detailed description of
this binding option. When the crossDomainIdAssertion
property
is set to true in Version 8.x, WS-Security
checks whether a SAML token contains a SAML Attribute UniqueSecurityName
with
a NameFormat
element with a value of com.ibm.websphere.security.cred.WSCredential
.
If found, WS-Security uses the NameQualifier
attribute
value of the NameID
element or NameIdentifier
element
to represent the user security realm name. WS-Security also uses the UniqueSecurityName
attribute
value and the GroupIds
attribute value to represent
a unique user name and group membership. This default behavior is
different between Version 7 and Version 8.x of the product. You can
add a CallbackHandler
property, IssuerNameForRealm
,
and set its value to true to configure Version
8.x to preserve the Version 7 behavior. Alternatively, you can add
a CallbackHandler
property, NameQualifierForRealm
,
and set its value to true to configure Version
8.x to always use the NameQualifier
attribute to
represent the user security realm name.
- Enable and configure WebSphere Application Server global
security.
You can use the Security Configuration wizard to enable administrative security. You also need to
enable application security so that the sample application can use the authenticated user subject in
the security context to create a SAML token. This step involves configuring the third trust
relationship verification point on the web services provider side. This step is needed to use the
application server for simulating the target security domain web services provider. The WebSphere Application Server V8.0 authentication subsystem supports asserting
user identity with a foreign realm name, and checks the foreign realm name against the list of
inbound trusted authentication realms. After you complete this configuration step, WebSphere
Application Server can create a client caller subject with a user identity in a foreign security
realm.
- Configure trusted security domains.
- From the Global Security panel, click Configure button beside
Available realm definitions.
- Click Trusted authentication realms - inbound
link.
- Choose Trust realms as indicated below option.
- Click Add External Realm button.
- Add the SAML assertion issuer name to External realm
name.
The SAML assertion issuer name provides information about the issuer of the SAML assertion, which
is either inside the Issuer element in the SAML 2.0 assertion, or is the Issuer attribute in the
SAML assertion.
Results
You have configured a web service to establish a client security
context using the SAML security token in the web services SOAP request
messages.
Example
The following example illustrates the NameIdentifier
and
Attribute
elements from a self-issued SAML 1.1 assertion based on
WSCredential
:<saml:AttributeStatement>
<saml:Subject>
<saml:NameIdentifier NameQualifier="ldap.example.com:9080">uid=alice,dc=example,dc=com</saml:NameIdentifier>
<saml:SubjectConfirmation>
<saml:ConfirmationMethod>urn:oasis:names:tc:SAML:1.0:cm:bearer</saml:ConfirmationMethod>
</saml:SubjectConfirmation>
</saml:Subject>
<saml:Attribute AttributeName="UniqueSecurityName" AttributeNamespace="com.ibm.websphere.security.cred.WSCredential">
<saml:AttributeValue>uid=alice,dc=example,dc=com</saml:AttributeValue>
</saml:Attribute>
<saml:Attribute AttributeName="GroupIds" AttributeNamespace="com.ibm.websphere.security.cred.WSCredential">
<saml:AttributeValue>cn=development,dc=example,dc=com</saml:AttributeValue>
<saml:AttributeValue>cn=deployment,dc=example,dc=com</saml:AttributeValue>
<saml:AttributeValue>cn=test,dc=example,dc=com</saml:AttributeValue>
</saml:Attribute>
</saml:AttributeStatement>
The
following example illustrates the
NameID
and
Attribute
elements
from a self-issued SAML 2.0 assertion based on
WSCredential
:
<saml2:AttributeStatement>
<saml2:Attribute Name="UniqueSecurityName" NameFormat="com.ibm.websphere.security.cred.WSCredential" />
<saml2:AttributeValue>uid=alice,dc=example,dc=com</saml2:AttributeValue>
<saml2:Attribute>
<saml2:Attribute AttributeName="GroupIds" NameFormat="com.ibm.websphere.security.cred.WSCredential" />
<saml2:AttributeValue>cn=development,dc=example,dc=com</saml2:AttributeValue>
<saml2:AttributeValue>cn=deployment,dc=example,dc=com</saml2:AttributeValue>
<saml2:AttributeValue>cn=test,dc=example,dc=com</saml2:AttributeValue>
</saml2:Attribute>
<saml2:AttributeStatement>
<saml2:NameID NameQualifier="ldap.example.com:9060">alice</saml2:NameID>