res_search only incremented got_servfail for h_errno == TRY_AGAIN *AND*
hp->rcode == SERVFAIL. However, there are cases such as timeouts where
rcode is not always set to SERVFAIL. This leads to inconsistent nameserver
operation during multi-domain and truncated dot searches, especially during
booting when portions of the network are being brought up simultanious with
dns lookups.
This patch attempts to correct the problem by unconditionally terminating
the search if TRY_AGAIN is returned (after res_query has gone through all
retries and name servers) instead of trying other domain elements in the
domain seach path.
This patch should fix reported problems (which I can reproduce) with some
NFS mounts failing during boot. This occured because mount_nfs thought the
host name lookup returned a definitive failure using a non-dotted host name
when, in fact, it timed out on the first part (host.search.domain.name) and
got a definitive host-not-found response on the second part (host.).
Generally speaking, search path name server timeouts can exceed 60 seconds
per element and most machines which consistently timeout on earlier portions
of a search path are effectively non-operational due to the imposed delays.
It is more important for DNS lookups to return the proper error code then
to be able to recover a valid lookup in later portions of the search path
in these situations.
Obtained from: DragonFly
MFC after: 3 weeks
Only warnings that could be fixed without changing the generated object
code and without restructuring the source code have been handled.
Reviewed by: /sbin/md5
insure enough space is available for the response, or be prepared
to resize the buffer and retry as necessary.
Do the conservative thing and make sure enough space is available.
Reviewed by: silence on freebsd-audit
IPv6 transport-ready resolvers/DNS servers. Need careful configuration
when enable it. (default config is not affected).
See manpage for details.
XXX visible symbol __res_opt() is added, however, it is not supposed to be
called from outside, libc minor is not bumped.
Obtained from: KAME/NetBSD
and res_* modules in a way that works for ELF. I moved the aliases
out of res_stubs.c and into the individual modules where the entry
points are defined. Weak aliases don't work in ELF unless that is
the case. (Actually, I'm surprised it worked for a.out.)
This should fix the undefined "inet_addr" and related symbols in
various applications that fail to include <arpa/inet.h> or
<resolv.h> as they are supposed to do.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
routines from contrib/bind directly. There were too many problems,
including having to add -DUSE_OPTIONS_H to the entire libc source in
order for the contrib code to pick up it's options, and so on.
Instead, I've merged the changes, libc is now self contained again.
Note that this was done by selective patching from diffs, to not conflict
with the 4.4bsd base code.. This was *not* a trivial task.. I have been
testing this code (apart from cosmetic changes) in my libc for a while now.
Obtained from: Paul Vixie <paul@vix.com>
