misc/54189: DNS resolver should resolve hostnames with underscores

[Jonathan Lennox]

>Number:         54189
>Category:       misc
>Synopsis:       DNS resolver should resolve hostnames with underscores
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jul 07 09:50:12 PDT 2003
>Closed-Date:
>Last-Modified:
>Originator:     Jonathan Lennox
>Release:        FreeBSD 4.8-RELEASE i386
>Organization:
Columbia University
>Environment:
System: FreeBSD conrail.cs.columbia.edu 4.8-RELEASE FreeBSD 4.8-RELEASE #4: Tue Apr 15 15:28:33 EDT 2003 lennox at conrail.cs.columbia.edu:/usr/obj/usr/src/sys/CONRAIL i386


>Description:
FreeBSD's gethostbyname() and getaddrinfo() functions refuse to resolve
hostnames with underscores in them.  They return the error codes NO_RECOVERY
and EAI_FAIL respectively.

Hostnames with underscores are ill-formed according to the DNS standards.
However, in the real Internet, hosts with underscores in their names are
reasonably common, and in many cases are not accessable through other names.

For example, the case that inspired me to file this PR: FreeBSD users are
unable to read the web log of the "Baghdad Blogger" Salam Pax, which is at
<http://dear_raed.blogspot.com>.  Linux and Windows users have no such
difficulty.

I note Jon Postel's maxim "Be liberal in what you accept, and conservative
in what you send."

(Note: this PR is in some sense a re-submission of PR misc/29388, but as a
change-request, not a sw-bug.)

>How-To-Repeat:
 Type "http://dear_raed.blogspot.com" into Mozilla running on FreeBSD.
Compare with Mozilla on other systems.

>Fix:
 Import BIND code from other Unix systems?
>Release-Note:
>Audit-Trail:
>Unformatted: