Shibboleth Debug Logging

As described on the main [[Shibboleth] page. EPrints uses the Shibboleth Service Provider (SP) provided by shibboleth.net. This includes a logger that can be configured at /etc/shibboleth/shibd.logger and which logs to /var/log/shibboleth/shibd.log. This typically only logs errors and warnings and the occasionally informationl log message, typically when starting or stopping. However, if you are having problems with the Shibboleth SP, particularly when setting up, it may be useful to enable debug. To do this

1. Edit the /etc/shibboleth/shibd.logger and uncomment the following lines:

# tracing of SAML messages and security policies
#log4j.category.OpenSAML.MessageDecoder=DEBUG
#log4j.category.OpenSAML.MessageEncoder=DEBUG
#log4j.category.OpenSAML.SecurityPolicyRule=DEBUG
#log4j.category.XMLTooling.SOAPClient=DEBUG
# interprocess message remoting
#log4j.category.Shibboleth.Listener=DEBUG
# mapping of requests to applicationId
#log4j.category.Shibboleth.RequestMapper=DEBUG
# high level session cache operations
#log4j.category.Shibboleth.SessionCache=DEBUG
# persistent storage and caching
#log4j.category.XMLTooling.StorageService=DEBUG

So they look like

# tracing of SAML messages and security policies
log4j.category.OpenSAML.MessageDecoder=DEBUG
log4j.category.OpenSAML.MessageEncoder=DEBUG
log4j.category.OpenSAML.SecurityPolicyRule=DEBUG
log4j.category.XMLTooling.SOAPClient=DEBUG
# interprocess message remoting
log4j.category.Shibboleth.Listener=DEBUG
# mapping of requests to applicationId
log4j.category.Shibboleth.RequestMapper=DEBUG
# high level session cache operations
log4j.category.Shibboleth.SessionCache=DEBUG
# persistent storage and caching
log4j.category.XMLTooling.StorageService=DEBUG

2. Test the Shibboleth SP is correctly configured

shibd -t

3. Restart the Shibboleth SP

systemctl restart shibd

There is various debugging that has been enabled by these changes. Particularly useful are the first two line:

log4j.category.OpenSAML.MessageDecoder=DEBUG
log4j.category.OpenSAML.MessageEncoder=DEBUG

This will allow you to see the XML messages sent to and from the Shibboleth Identity Provider (IdP), such as MicroSoft Entra or OpenAthens.

Debugging User Attributes Mapping Issues

This debugging can be particularly useful if you are trying to work attributes in your attribute-map.xml are not being mapped as expected. If you tail the log file /var/log/shibboleth/shibd.log and then try to login using the Shibboleth, you should see a line in the logs that starts:

<samlp:Response ...

If you copy the whole of that line into a text file in /tmp/ and save it. Then you can run xmllint on it to format the output. E.g.

xmllint --format /tmp/saml-response.xml

If attributes are being mapped, in the formatted output you should be able to see section that starts with an AttributeStatment XML tag. E.g.

<AttributeStatement>
  <Attribute Name="http://schemas.microsoft.com/identity/claims/tenantid">
    <AttributeValue>01234567-89ab-cdef-0123-456789abcdef</AttributeValue>
  </Attribute>
  <Attribute Name="http://schemas.microsoft.com/identity/claims/objectidentifier">
    <AttributeValue>fedcba98-7654-3210-fedc-ba9876543210</AttributeValue>
  </Attribute>
  <Attribute Name="http://schemas.microsoft.com/identity/claims/identityprovider">
    <AttributeValue>https://sts.windows.net/89abcdef-0123-4567-89ab-cdef01234567/</AttributeValue>
  </Attribute>
  <Attribute Name="http://schemas.microsoft.com/claims/authnmethodsreferences">
    <AttributeValue>http://schemas.microsoft.com/ws/2008/06/identity/authenticationmethod/password</AttributeValue>
    <AttributeValue>http://schemas.microsoft.com/claims/multipleauthn</AttributeValue>
  </Attribute>
  <Attribute Name="urn:oid:0.9.2342.19200300.100.1.3">
    <AttributeValue>j.bloggs@example.org</AttributeValue>
  </Attribute>
  <Attribute Name="urn:oid:2.5.4.4">
    <AttributeValue>Bloggs</AttributeValue>
  </Attribute>
  <Attribute Name="urn:oid:2.5.4.42">
    <AttributeValue>Joe</AttributeValue>
  </Attribute>
</AttributeStatement>

If you cannot find users attributes you are expecting to see based on what you have configurured in your Shibboleth SP's attribute-map.xml, then you will need to get the maintainer of Shibboleth IdP to make sure these attributes are released or otherwise release attributes that store the sane user metadata. At this point you can re-run this debugging to see what user attributes you are now getting and update your Shibboleth SP's attribute-map.xml as appropriate.

When you have finished debugging. It is sensible to comment out the debug lines in /etc/shibboleth/shibd.logger again and restart the Shibboleth SP.