bin/176713: [patch] nc(1) closes network socket too soon

Sat Jul 20 15:58:54 UTC 2013

On Sat, Jul 20, 2013 at 4:31 PM, Ronald F. Guilmette
<rfg at tristatelogic.com>wrote:

>
>
> Could someone please take a look at this bug report (bin/176713) and
> also at the simple patch that I provided to fix the problem?
>
> This is quite a serious problem, and my PR has been pending with no
> action since Wed, 6 Mar 2013.
>
>
> Regards,
> rfg
>
>
> P.S.  Please note that in reality, I do not believe that it is necessary
> to add a new -q option in order to preserve backwards compatability,
> however
> I proposed one because in my experience there is always going to be some
> purist who will claim that *any* change in semantics, however small or
> helpful, in *any* software ``may'' break something.  In reality, the
> problem in this can most easily be solved simply by removing the one
> statement:
>
>         shutdown(nfd, SHUT_WR);
>
> entirely from the source, rather than making it conditional on -q, as I
> suggested in my PR, bin/176713.
>

It seems to work for me:

Old version:

$ echo 193.0.6.139 | nc whois.ripe.net 43
% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See http://www.ripe.net/db/support/db-terms-conditions.pdf

with the patched version:

echo 193.0.6.139 | ./nc -q whois.ripe.net 43
% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See http://www.ripe.net/db/support/db-terms-conditions.pdf

% Note: this output has been filtered.
%       To receive output for a database update, use the "-B" flag.

% Information related to '193.0.0.0 - 193.0.7.255'

% Abuse contact for '193.0.0.0 - 193.0.7.255' is 'abuse at ripe.net'

inetnum:        193.0.0.0 - 193.0.7.255
netname:        RIPE-NCC
descr:          RIPE Network Coordination Centre
org:            ORG-RIEN1-RIPE
descr:          Amsterdam, Netherlands
remarks:        Used for RIPE NCC infrastructure.
country:        NL
admin-c:        JDR-RIPE
admin-c:        BRD-RIPE
tech-c:         OPS4-RIPE
status:         ASSIGNED PI
source:         RIPE # Filtered
mnt-by:         RIPE-NCC-MNT
mnt-lower:      RIPE-NCC-MNT

organisation:   ORG-RIEN1-RIPE
org-name:       Reseaux IP Europeens Network Coordination Centre (RIPE NCC)
org-type:       RIR
descr:          RIPE NCC Operations
address:        Reseaux IP Europeens Network Coordination Centre (RIPE NCC)
                P.O. Box 10096
                1016 EB Amsterdam
                Netherlands
phone:          +31205354444
fax-no:         +31205354445
admin-c:        AP110-RIPE
admin-c:        MENN1-RIPE
abuse-c:        ops4-ripe
mnt-ref:        RIPE-NCC-MNT
mnt-ref:        RIPE-NCC-HM-MNT
mnt-by:         RIPE-NCC-HM-MNT
source:         RIPE # Filtered

role:           RIPE NCC Operations
address:        Singel 258
address:        1016 AB Amsterdam
address:        The Netherlands
phone:          +31 20 535 4444
fax-no:         +31 20 535 4445
abuse-mailbox:  abuse at ripe.net
admin-c:        JDR-RIPE
admin-c:        BRD-RIPE
tech-c:         GL7321-RIPE
tech-c:         JA47
tech-c:         MENN1-RIPE
tech-c:         EMIL-RIPE
tech-c:         RCO-RIPE
tech-c:         APZ-RIPE
tech-c:         CNAG-RIPE
tech-c:         RPM-RIPE
tech-c:         SO2011-RIPE
tech-c:         RH5357-RIPE
tech-c:         DCW-RIPE
tech-c:         FMUL-RIPE
nic-hdl:        OPS4-RIPE
mnt-by:         RIPE-NCC-MNT
source:         RIPE # Filtered

person:         Brian Riddle
address:        IT Manager
address:        RIPE NCC - Operations
address:        Singel 258
address:        1016AB Amsterdam
address:        The Netherlands
phone:          +31 20 535 4444
fax-no:         +31 20 535 4445
nic-hdl:        BRD-RIPE
source:         RIPE # Filtered
mnt-by:         RIPE-NCC-MNT

person:         Jochem de Ruig
address:        RIPE NCC
address:        Singel 258
address:        1016AB Amsterdam
address:        The Netherlands
phone:          +31 20 535 4444
fax-no:         +31 20 535 4445
nic-hdl:        JDR-RIPE
source:         RIPE # Filtered
mnt-by:         RIPE-NCC-MNT

% Information related to '193.0.0.0/21AS3333'

route:          193.0.0.0/21
descr:          RIPE-NCC
origin:         AS3333
mnt-by:         RIPE-NCC-MNT
source:         RIPE # Filtered

% This query was served by the RIPE Database Query Service version 1.66.3
(WHOIS2)

Tested on:

FreeBSD hammer 9.1-RELEASE-p3 FreeBSD 9.1-RELEASE-p3 #0: Mon Apr 29
18:27:25 UTC 2013
root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC
amd64

>
> P.P.S.  I have just realized that yet one more critical enhancement for
> nc is called for, and I will be filing a separate and additional PR for
> that soon.  I hope that someone will be able to take a look at that as
> soon as it is filed.
>

Just out of curiosity. What is it about?

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