Encrypted SLO Requests Fail

[pdspicer]

With the following (valid) SAML LogoutRequest, passport-saml fails to process the request as there it has no support in IDP-initiated SLO for decryption of Encrypted NameIDs:

<?xml version="1.0" encoding="UTF-8"?>
<saml2p:LogoutRequest Destination="https://localhost:8000/saml2/slo" ID="_14ce3210bed9ccf3227d9f380d8b3230" IssueInstant="2017-03-27T20:35:20.595Z" Version="2.0" xmlns:saml2p="urn:oasis:names:tc:SAML:2.0:protocol">
  <saml2:Issuer xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion">https://localhost:4443/idp/shibboleth</saml2:Issuer>
  <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
    Omitted for brevity
  </ds:Signature>
  <saml2:EncryptedID xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion">
    <xenc:EncryptedData Id="_45c5f58c6bd745b6174a5c04fd510f91" Type="http://www.w3.org/2001/04/xmlenc#Element" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
      <xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#aes256-cbc" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"/>
      <ds:KeyInfo xmlns:ds="http://www.w3.org/2000/09/xmldsig#">Omitted for brevity</ds:KeyInfo>
      <xenc:CipherData xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
        <xenc:CipherValue>Omitted for brevity</xenc:CipherValue>
      </xenc:CipherData>
    </xenc:EncryptedData>
  </saml2:EncryptedID>
  <saml2p:SessionIndex>_dde31adec05f7316ca073fcafffed219</saml2p:SessionIndex>
</saml2p:LogoutRequest>

This request is from Shibboleth IDP 3.2.1

[nkovalenko-sc]

The same problem with shibboleth.

[ryanmartinneutrino]

I have the same issue, also with Shibboleth. Would it be possible to have the PR reviewed and merged, I'm surprised that so few people have this issue.

[ricardosaracino]

Can someone point me in the direction of how to add aes256-cbc Assertion encryption support... i see this lib but not sure how to put it all together

https://github.com/auth0/node-xml-encryption

[hagis]

We also need this fixed. Please review and merge the PR.