bin/139405: DHCP server with two interfaces connected to one physical network

[sobotap]

>Number:         139405
>Category:       bin
>Synopsis:       DHCP server with two interfaces connected to one physical network
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Oct 07 15:40:01 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     sobotap
>Release:        8.0-CURRENT-200809
>Organization:
Warsaw University of Technology
>Environment:
FreeBSD volt.iem.pw.edu.pl 8.0-CURRENT-200809 FreeBSD 9.0-CURRENT #0: Tue Sep 22 13:21:47 CEST 2009     ato at volt.iem.pw.edu.pl:/tmp/obj/usr/src/sys/VOLT  amd64
>Description:
Internet Software Consortium DHCP Server V3.0.1rc12pxe2

sk0:  1.1.1.3 (public IP)
nve0: 10.10.0.3 (private IP)

/etc/dhcpd.conf
---------------

shared-network "xxxx" {
  subnet 1.1.1.0 netmask 255.255.255.0 {
    authoritative;
    option domain-name-servers 1.1.1.3;
    option routers 1.1.1.1;
  }
}

subnet 10.10.0.0 netmask 255.255.0.0 {
  authoritative;
  option routers 10.10.0.3;
  option domain-name-servers 10.10.0.3;
  # unknown clients MAC
  pool {
    allow unknown clients;
    range 10.10.0.100 10.10.0.250;
  }
}

host abcd { hardware ethernet 00:11:22:33:44:55; fixed-address 1.1.1.5; }
host efgh { hardware ethernet 00:22:44:66:88:99; fixed-address 10.10.0.5; }

server dhcp listening on sk0 and nve0
both interfaces are connected to ine physical network

Client abcd (public IP) sends DHCPDISCOVER,
dhcp server logs next information,
**** dhcpd: DHCPDISCOVER from 00:11:22:33:44:55 via nve0: network 10.10.0.0/16: no free leases
**** dhcpd: DHCPDISCOVER from 00:11:22:33:44:55 via sk0
server dhcp response DHCPOFFER: 1.1.1.5,
client sends DHCPREQUEST: 1.1.1.5,
if server DHCP get this request at first via nve0
and then get this request at next via sk0
server DHCP at first send DHCPNAK and next send DHCPACK
in accordion with RFC client starts DHCP dialogue from beginning.
Changing order interfaces on which server dhcp in listening
do the same problem for client efhg (private IP).

>How-To-Repeat:

>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: