Bug Report from www.isc.org:

Name: Darren Ankney
Email: dankney@network1.net
Software Version: Internet Systems Consortium DHCP Server 4.3.3
OS: generic Linux 3.19.0
Subject:on commit {} in DHCPv6 has client option content instead of server option content


Bug Detail
===========
Original thread on DHCP users here: https://lists.isc.org/pipermail/dhcp-users/2016-December/020485.html

having something like this in the dhcpd.conf file for DHCPv6: 

on commit { 
     if exists dhcp6.ia-na { 
          log(debug, 
               concat( "LEASED,", 
                    "IPTIME,",binary-to-ascii(10, 32, "", substring(option dhcp6.ia-na,36,4)),"," 
               ) 
          ); 
     } 
} 

Will produce a value for IPTIME that is equal to the time requested by the client instead of what was given by the server. 

For example: 

Client (Redhat Enterprise Linux 7 - ISC DHCP 4.2.5) sends a Renew for an IPv6 address via DHCPv6 requesting the following times (As seen in wireshark capture): 

T1: 3600 
T2: 5400 
Preferred Lifetime: 7200 
Valid Lifetime: 7500 

Server (generic Linux - ISC DHCP 4.3.3) is configured with this time setting in the pool6 {} statement: 

default-lease-time 600; 

Server responds with times like this (as seen in wireshark capture): 

T1: 0 
T2: 0 
Preferred Lifetime: 375 
Valid Lifetime: 600 

What is logged in the log file is 7500 not 600. 

The client lease file shows the following times: 

Renew: 0 
Rebind: 0 
Preferred Lifetime: 375 
Valid Lifetime: 600 

So, it seems that the dhcp options available in on commit {} are what the client sent in instead of those the server sent in response? Is that a bug? Or do I not understand how on commit {} works? I assumed that on commit {} would have access to the options as set by the server that were sent back to the client. 

It seems like a bug to me as the man page for DHCP options (man dhcp-options(5)) states that the option is produced by the server:

option dhcp6.ia-na string;

         The Identity Association for Non-temporary Addresses (ia-na) carries assigned addresses that are not temporary addresses for use by the DHCPv6 client.  This option is produced by the DHCPv6 server software, and should not be configured.

---
This email was received through isc.org Bug Submission Form