[HADOOP-12617] SPNEGO authentication request to non-default realm gets default realm name inserted in target server principal

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.7.1
• Fix Version/s: 2.8.0, 3.0.0-alpha1
• Component/s: security

Environment

Java client talking to two secure clusters in different Kerberos realms,
or talking to any secure cluster in non-default realm

• Target Version/s: 2.8.0
• Assignee: Matt Foley
• Reporter: Matt Foley
• Created: 06/Dec/15 22:00
• Updated: 30/Aug/16 01:21
• Resolved: 09/Dec/15 01:53

Description

Note: This is NOT a vulnerability.

In order for a single Java client to communicate with two different secure clusters in different realms (only one of which can be the "default_realm"), the client's krb5.conf file must specify both realms, and provide a [domain_realm] section that maps cluster servers' domains to the correct realms. With other appropriate behaviors (such as using the config from each cluster to talk to the respective clusters, and a user principal from each realm to talk to the respective realms), this is sufficient for most Hadoop ecosystem clients.

But our SPNEGO using clients, such as Oozie, have a bug when it comes to talking to a non-default realm. The default realm name gets incorrectly inserted into the construction of the target server principal for the non-default-realm cluster. Details and proposed solution are given in the first comments below.