[DIRKRB-734] Miss-calculation of Bytes Read For Entry in Keytab

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.1.2, 2.0.1
• Assignee: Colm O hEigeartaigh
• Reporter: Farhan Khan
• Created: 30/Apr/19 17:21
• Updated: 03/Jun/20 09:36
• Resolved: 01/May/19 14:16

Description

When using to read principal from a keytab file generated by a heimdal-kdc (version 7.5.0), it is throwing error because of miss-calculation of number of bytes read for an entry. The error is as follows:

java.io.IOException: Unexpected octets len: 16716
    at org.apache.kerby.kerberos.kerb.KrbInputStream.readCountedOctets(KrbInputStream.java:72)
    at org.apache.kerby.kerberos.kerb.KrbInputStream.readKey(KrbInputStream.java:48)
    at org.apache.kerby.kerberos.kerb.keytab.KeytabEntry.load(KeytabEntry.java:55)
    at org.apache.kerby.kerberos.kerb.keytab.Keytab.readEntry(Keytab.java:203)
    at org.apache.kerby.kerberos.kerb.keytab.Keytab.readEntries(Keytab.java:189)
    at org.apache.kerby.kerberos.kerb.keytab.Keytab.doLoad(Keytab.java:161)
    at org.apache.kerby.kerberos.kerb.keytab.Keytab.load(Keytab.java:155)
    at org.apache.kerby.kerberos.kerb.keytab.Keytab.load(Keytab.java:143)
    at org.apache.kerby.kerberos.kerb.keytab.Keytab.loadKeytab(Keytab.java:55)

The part of the code which is responsible for this error is https://github.com/apache/directory-kerby/blob/507c74bc3547e80b7102d3b7e5c753e67b60fb9a/kerby-kerb/kerb-util/src/main/java/org/apache/kerby/kerberos/kerb/keytab/Keytab.java#L199. Here, we are trying to calculate the number of bytes read for an entry. But we are not considering the number of bytes denoting the size of an entry, which should be excluded from the calculation of bytes read for an entry.

Issue Links

• relates to: HADOOP-16283 Error in reading Kerberos principals from the Keytab file
• links to: GitHub Pull Request #44