2004-03-05 05:14:21 +00:00
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Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC")
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2001-01-09 22:01:04 +00:00
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Copyright (C) 1999-2001 Internet Software Consortium.
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2000-08-09 04:37:43 +00:00
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See COPYRIGHT in the source root or http://isc.org/copyright.html for terms.
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1999-04-10 00:37:31 +00:00
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2004-03-05 05:14:21 +00:00
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$Id: ncache,v 1.7 2004/03/05 05:04:46 marka Exp $
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2000-06-22 22:00:42 +00:00
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1999-04-10 00:37:31 +00:00
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Negative Caching
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The non-DNSSEC case is pretty easy.
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foundname = soa name
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rdataset = soa
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node = NULL
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DNSSEC complicates things a lot, because we have to return one or more NXT
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records (if we have them) as proof. Another tricky bit here is that we may
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have an NXT record so we know the answer is NODATA, but we don't have the SOA
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so we can't make a NODATA response that a non-DNSSEC-aware server could
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cache. Life would sure be easier if we knew if the client understood DNSSEC.
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Not sure what to do in this case. Probably return delegation to force client
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to ask authority.
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2000-08-01 01:33:37 +00:00
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Perhaps we should just create some kind of meta-rdata, the "negative cache
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1999-04-10 00:37:31 +00:00
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rdata type"?
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Or maybe something like:
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dns_rdataset_ncachefirst()
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dns_rdataset_ncachenext()
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dns_rdataset_ncachecurrent()
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dns_db_ncachenew(db, type) /* type can be any */
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dns_db_ncachesoa(name, rdataset)
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dns_db_ncachenxt(name, rdataset)
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dns_db_ncacheadd(db, name, version)
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Ick. I favor the former.
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