bin/82306: PPP ip-pool regression due CARP implementation

[Boris Kovalenko]

>Number:         82306
>Category:       bin
>Synopsis:       PPP ip-pool regression due CARP implementation
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Jun 16 05:00:43 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Boris Kovalenko
>Release:        FreeBSD 5.4-STABLE i386
>Organization:
JSC "TAGNet"
>Environment:
System: FreeBSD boris.nikom.ru 5.4-STABLE FreeBSD 5.4-STABLE #1: Wed May 11 09:37:01 YEKST 2005 root at boris.nikom.ru:/usr/obj/usr/src/sys/BSYS i386
>Description:
	I use FreeBSD as PPPoE dialin server. The configuration is very simple
pppoe:
    enable pap
    disable chap
    allow mode direct
    set mru 1492
    set mtu 1492
    set speed sync
    set ifaddr x.x.x.254 x.x.x.225-x.x.x.250 255.255.255.255
    set dns x.x.x.1
    enable dns
    accept dns
    set timeout 3600
    enable lqr echo
    set lqrperiod  15
    set echoperiod 15

    There was no problems with this configuration in 4.9 and 5.2.1 branches. But when I
    have upgraded to 5.4 - ppp began to assign duplicate ips to clients!!! So, clients
    are stop working. Gleb Smirnoff explained that problem is with CARP implementation 
    where some check for duplicating ips was removed from kernel. But this makes 
    /usr/sbin/ppp ip-pool feature useless, and even this is regression! 
    Now we can not use ppp without RADIUS (which should support of ip-pool feature itself).
													
>How-To-Repeat:
	Try to make ppp dialin server with 5.4 and connect many clients to it
>Fix:
	Really don't know how. But IMHO we should introduce some option like (disable carp)
	and implement duplicate ip checking in ppp code.

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