diff options
Diffstat (limited to 'contrib/bind9/lib/dns/nsec.c')
| -rw-r--r-- | contrib/bind9/lib/dns/nsec.c | 161 |
1 files changed, 160 insertions, 1 deletions
diff --git a/contrib/bind9/lib/dns/nsec.c b/contrib/bind9/lib/dns/nsec.c index 72d1751..41b5dc3 100644 --- a/contrib/bind9/lib/dns/nsec.c +++ b/contrib/bind9/lib/dns/nsec.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2004, 2005, 2007-2009, 2011, 2012 Internet Systems Consortium, Inc. ("ISC") + * Copyright (C) 2004, 2005, 2007-2009, 2011-2013 Internet Systems Consortium, Inc. ("ISC") * Copyright (C) 1999-2001, 2003 Internet Software Consortium. * * Permission to use, copy, modify, and/or distribute this software for any @@ -21,6 +21,7 @@ #include <config.h> +#include <isc/log.h> #include <isc/string.h> #include <isc/util.h> @@ -275,3 +276,161 @@ dns_nsec_nseconly(dns_db_t *db, dns_dbversion_t *version, } return (result); } + +/*% + * Return ISC_R_SUCCESS if we can determine that the name doesn't exist + * or we can determine whether there is data or not at the name. + * If the name does not exist return the wildcard name. + * + * Return ISC_R_IGNORE when the NSEC is not the appropriate one. + */ +isc_result_t +dns_nsec_noexistnodata(dns_rdatatype_t type, dns_name_t *name, + dns_name_t *nsecname, dns_rdataset_t *nsecset, + isc_boolean_t *exists, isc_boolean_t *data, + dns_name_t *wild, dns_nseclog_t logit, void *arg) +{ + int order; + dns_rdata_t rdata = DNS_RDATA_INIT; + isc_result_t result; + dns_namereln_t relation; + unsigned int olabels, nlabels, labels; + dns_rdata_nsec_t nsec; + isc_boolean_t atparent; + isc_boolean_t ns; + isc_boolean_t soa; + + REQUIRE(exists != NULL); + REQUIRE(data != NULL); + REQUIRE(nsecset != NULL && + nsecset->type == dns_rdatatype_nsec); + + result = dns_rdataset_first(nsecset); + if (result != ISC_R_SUCCESS) { + (*logit)(arg, ISC_LOG_DEBUG(3), "failure processing NSEC set"); + return (result); + } + dns_rdataset_current(nsecset, &rdata); + + (*logit)(arg, ISC_LOG_DEBUG(3), "looking for relevant NSEC"); + relation = dns_name_fullcompare(name, nsecname, &order, &olabels); + + if (order < 0) { + /* + * The name is not within the NSEC range. + */ + (*logit)(arg, ISC_LOG_DEBUG(3), + "NSEC does not cover name, before NSEC"); + return (ISC_R_IGNORE); + } + + if (order == 0) { + /* + * The names are the same. If we are validating "." + * then atparent should not be set as there is no parent. + */ + atparent = (olabels != 1) && dns_rdatatype_atparent(type); + ns = dns_nsec_typepresent(&rdata, dns_rdatatype_ns); + soa = dns_nsec_typepresent(&rdata, dns_rdatatype_soa); + if (ns && !soa) { + if (!atparent) { + /* + * This NSEC record is from somewhere higher in + * the DNS, and at the parent of a delegation. + * It can not be legitimately used here. + */ + (*logit)(arg, ISC_LOG_DEBUG(3), + "ignoring parent nsec"); + return (ISC_R_IGNORE); + } + } else if (atparent && ns && soa) { + /* + * This NSEC record is from the child. + * It can not be legitimately used here. + */ + (*logit)(arg, ISC_LOG_DEBUG(3), + "ignoring child nsec"); + return (ISC_R_IGNORE); + } + if (type == dns_rdatatype_cname || type == dns_rdatatype_nxt || + type == dns_rdatatype_nsec || type == dns_rdatatype_key || + !dns_nsec_typepresent(&rdata, dns_rdatatype_cname)) { + *exists = ISC_TRUE; + *data = dns_nsec_typepresent(&rdata, type); + (*logit)(arg, ISC_LOG_DEBUG(3), + "nsec proves name exists (owner) data=%d", + *data); + return (ISC_R_SUCCESS); + } + (*logit)(arg, ISC_LOG_DEBUG(3), "NSEC proves CNAME exists"); + return (ISC_R_IGNORE); + } + + if (relation == dns_namereln_subdomain && + dns_nsec_typepresent(&rdata, dns_rdatatype_ns) && + !dns_nsec_typepresent(&rdata, dns_rdatatype_soa)) + { + /* + * This NSEC record is from somewhere higher in + * the DNS, and at the parent of a delegation. + * It can not be legitimately used here. + */ + (*logit)(arg, ISC_LOG_DEBUG(3), "ignoring parent nsec"); + return (ISC_R_IGNORE); + } + + result = dns_rdata_tostruct(&rdata, &nsec, NULL); + if (result != ISC_R_SUCCESS) + return (result); + relation = dns_name_fullcompare(&nsec.next, name, &order, &nlabels); + if (order == 0) { + dns_rdata_freestruct(&nsec); + (*logit)(arg, ISC_LOG_DEBUG(3), + "ignoring nsec matches next name"); + return (ISC_R_IGNORE); + } + + if (order < 0 && !dns_name_issubdomain(nsecname, &nsec.next)) { + /* + * The name is not within the NSEC range. + */ + dns_rdata_freestruct(&nsec); + (*logit)(arg, ISC_LOG_DEBUG(3), + "ignoring nsec because name is past end of range"); + return (ISC_R_IGNORE); + } + + if (order > 0 && relation == dns_namereln_subdomain) { + (*logit)(arg, ISC_LOG_DEBUG(3), + "nsec proves name exist (empty)"); + dns_rdata_freestruct(&nsec); + *exists = ISC_TRUE; + *data = ISC_FALSE; + return (ISC_R_SUCCESS); + } + if (wild != NULL) { + dns_name_t common; + dns_name_init(&common, NULL); + if (olabels > nlabels) { + labels = dns_name_countlabels(nsecname); + dns_name_getlabelsequence(nsecname, labels - olabels, + olabels, &common); + } else { + labels = dns_name_countlabels(&nsec.next); + dns_name_getlabelsequence(&nsec.next, labels - nlabels, + nlabels, &common); + } + result = dns_name_concatenate(dns_wildcardname, &common, + wild, NULL); + if (result != ISC_R_SUCCESS) { + dns_rdata_freestruct(&nsec); + (*logit)(arg, ISC_LOG_DEBUG(3), + "failure generating wildcard name"); + return (result); + } + } + dns_rdata_freestruct(&nsec); + (*logit)(arg, ISC_LOG_DEBUG(3), "nsec range ok"); + *exists = ISC_FALSE; + return (ISC_R_SUCCESS); +} |
