captive-validator/src/com/versign/tat/dnssec/NSEC3ValUtils.java

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/*
* $Id$
*
* Copyright (c) 2006 VeriSign. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution. 3. The name of the author may not
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
package com.versign.tat.dnssec;
import java.security.NoSuchAlgorithmException;
import java.util.*;
import org.xbill.DNS.*;
import org.xbill.DNS.utils.base32;
import com.versign.tat.dnssec.SignUtils.ByteArrayComparator;
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public class NSEC3ValUtils
{
// FIXME: should probably refactor to handle different NSEC3 parameters more
// efficiently.
// Given a list of NSEC3 RRs, they should be grouped according to
// parameters. The idea is to hash and compare for each group independently,
// instead of having to skip NSEC3 RRs with the wrong parameters.
private static Name asterisk_label = Name.fromConstantString("*");
/**
* This is a class to encapsulate a unique set of NSEC3 parameters:
* algorithm, iterations, and salt.
*/
private static class NSEC3Parameters
{
public byte alg;
public byte[] salt;
public int iterations;
public NSEC3Parameters(NSEC3Record r)
{
alg = r.getHashAlgorithm();
salt = r.getSalt();
iterations = r.getIterations();
}
public boolean match(NSEC3Record r, ByteArrayComparator bac)
{
if (r.getHashAlgorithm() != alg) return false;
if (r.getIterations() != iterations) return false;
if (salt == null && r.getSalt() != null) return false;
if (bac == null) bac = new ByteArrayComparator();
return bac.compare(r.getSalt(), salt) == 0;
}
}
/**
* This is just a simple class to enapsulate the response to a closest
* encloser proof.
*/
private static class CEResponse
{
public Name closestEncloser;
public NSEC3Record ce_nsec3;
public NSEC3Record nc_nsec3;
public CEResponse(Name ce, NSEC3Record nsec3)
{
this.closestEncloser = ce;
this.ce_nsec3 = nsec3;
}
}
public static boolean supportsHashAlgorithm(int alg)
{
if (alg == NSEC3Record.SHA1_DIGEST_ID) return true;
return false;
}
public static void stripUnknownAlgNSEC3s(List nsec3s)
{
if (nsec3s == null) return;
for (ListIterator i = nsec3s.listIterator(); i.hasNext(); )
{
NSEC3Record nsec3 = (NSEC3Record) i.next();
if (!supportsHashAlgorithm(nsec3.getHashAlgorithm()))
{
i.remove();
}
}
}
/**
* Given a list of NSEC3Records that are part of a message, determine the
* NSEC3 parameters (hash algorithm, iterations, and salt) present. If there
* is more than one distinct grouping, return null;
*
* @param nsec3s A list of NSEC3Record object.
* @return A set containing a number of objects (NSEC3Parameter objects)
* that correspond to each distinct set of parameters, or null if
* the nsec3s list was empty.
*/
public static NSEC3Parameters nsec3Parameters(List nsec3s)
{
if (nsec3s == null || nsec3s.size() == 0) return null;
NSEC3Parameters params = new NSEC3Parameters((NSEC3Record) nsec3s.get(0));
ByteArrayComparator bac = new ByteArrayComparator();
for (Iterator i = nsec3s.iterator(); i.hasNext();)
{
if (! params.match((NSEC3Record) i.next(), bac))
{
return null;
}
}
return params;
}
/**
* In a list of NSEC3Record object pulled from a given message, find the
* NSEC3 that directly matches a given name, without hashing.
*
* @param n The name in question.
* @param nsec3s A list of NSEC3Records from a given message.
* @return The matching NSEC3Record, or null if there wasn't one.
*/
// private static NSEC3Record findDirectMatchingNSEC3(Name n, List nsec3s)
// {
// if (n == null || nsec3s == null) return null;
//
// for (Iterator i = nsec3s.iterator(); i.hasNext();)
// {
// NSEC3Record nsec3 = (NSEC3Record) i.next();
// if (n.equals(nsec3.getName())) return nsec3;
// }
//
// return null;
// }
/**
* Given a hash and an a zone name, construct an NSEC3 ownername.
*
* @param hash The hash of an original name.
* @param zonename The zone to use in constructing the NSEC3 name.
* @return The NSEC3 name.
*/
private static Name hashName(byte[] hash, Name zonename)
{
try
{
return new Name(base32.toString(hash).toLowerCase(), zonename);
}
catch (TextParseException e)
{
// Note, this should never happen.
return null;
}
}
/**
* Given a set of NSEC3 parameters, hash a name.
*
* @param name The name to hash.
* @param params The parameters to hash with.
* @return The hash.
*/
private static byte[] hash(Name name, NSEC3Parameters params)
{
try
{
return NSEC3Record.hash(name,
params.alg,
params.iterations,
params.salt);
}
catch (NoSuchAlgorithmException e)
{
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// st_log.debug("Did not recognize hash algorithm: " + params.alg);
return null;
}
}
/**
* Given the name of a closest encloser, return the name *.closest_encloser.
*
* @param closestEncloser The name to start with.
* @return The wildcard name.
*/
private static Name ceWildcard(Name closestEncloser)
{
try
{
Name wc = Name.concatenate(asterisk_label, closestEncloser);
return wc;
}
catch (NameTooLongException e)
{
return null;
}
}
/**
* Given a qname and its proven closest encloser, calculate the "next
* closest" name. Basically, this is the name that is one label longer than
* the closest encloser that is still a subdomain of qname.
*
* @param qname The qname.
* @param closestEncloser The closest encloser name.
* @return The next closer name.
*/
private static Name nextClosest(Name qname, Name closestEncloser)
{
int strip = qname.labels() - closestEncloser.labels() - 1;
return (strip > 0) ? new Name(qname, strip) : qname;
}
/**
* Find the NSEC3Record that matches a hash of a name.
*
* @param hash The pre-calculated hash of a name.
* @param zonename The name of the zone that the NSEC3s are from.
* @param nsec3s A list of NSEC3Records from a given message.
* @param params The parameters used for calculating the hash.
* @param bac An already allocated ByteArrayComparator, for reuse. This may
* be null.
*
* @return The matching NSEC3Record, if one is present.
*/
private static NSEC3Record findMatchingNSEC3(byte[] hash, Name zonename,
List nsec3s, NSEC3Parameters params, ByteArrayComparator bac)
{
Name n = hashName(hash, zonename);
for (Iterator i = nsec3s.iterator(); i.hasNext();)
{
NSEC3Record nsec3 = (NSEC3Record) i.next();
// Skip nsec3 records that are using different parameters.
if (!params.match(nsec3, bac)) continue;
if (n.equals(nsec3.getName())) return nsec3;
}
return null;
}
/**
* Given a hash and a candidate NSEC3Record, determine if that NSEC3Record
* covers the hash. Covers specifically means that the hash is in between
* the owner and next hashes and does not equal either.
*
* @param nsec3 The candidate NSEC3Record.
* @param hash The precalculated hash.
* @param bac An already allocated comparator. This may be null.
* @return True if the NSEC3Record covers the hash.
*/
private static boolean nsec3Covers(NSEC3Record nsec3, byte[] hash,
ByteArrayComparator bac)
{
byte[] owner = nsec3.getOwner();
byte[] next = nsec3.getNext();
// This is the "normal case: owner < next and owner < hash < next
if (bac.compare(owner, hash) < 0 && bac.compare(hash, next) < 0)
return true;
// this is the end of zone case: next < owner && hash > owner || hash <
// next
if (bac.compare(next, owner) <= 0
&& (bac.compare(hash, next) < 0 || bac.compare(owner, hash) < 0))
return true;
// Otherwise, the NSEC3 does not cover the hash.
return false;
}
/**
* Given a pre-hashed name, find a covering NSEC3 from among a list of
* NSEC3s.
*
* @param hash The hash to consider.
* @param zonename The name of the zone.
* @param nsec3s The list of NSEC3s present in a message.
* @param params The NSEC3 parameters used to generate the hash -- NSEC3s
* that do not use those parameters will be skipped.
*
* @return A covering NSEC3 if one is present, null otherwise.
*/
private static NSEC3Record findCoveringNSEC3(byte[] hash, Name zonename,
List nsec3s, NSEC3Parameters params, ByteArrayComparator bac)
{
ByteArrayComparator comparator = new ByteArrayComparator();
for (Iterator i = nsec3s.iterator(); i.hasNext();)
{
NSEC3Record nsec3 = (NSEC3Record) i.next();
if (!params.match(nsec3, bac)) continue;
if (nsec3Covers(nsec3, hash, comparator)) return nsec3;
}
return null;
}
/**
* Given a name and a list of NSEC3s, find the candidate closest encloser.
* This will be the first ancestor of 'name' (including itself) to have a
* matching NSEC3 RR.
*
* @param name The name the start with.
* @param zonename The name of the zone that the NSEC3s came from.
* @param nsec3s The list of NSEC3s.
* @param nsec3params The NSEC3 parameters.
* @param bac A pre-allocated comparator. May be null.
*
* @return A CEResponse containing the closest encloser name and the NSEC3
* RR that matched it, or null if there wasn't one.
*/
private static CEResponse findClosestEncloser(Name name, Name zonename,
List nsec3s, NSEC3Parameters params, ByteArrayComparator bac)
{
Name n = name;
NSEC3Record nsec3;
// This scans from longest name to shortest, so the first match we find is
// the only viable candidate.
// FIXME: modify so that the NSEC3 matching the zone apex need not be
// present.
while (n.labels() >= zonename.labels())
{
nsec3 = findMatchingNSEC3(hash(n, params), zonename, nsec3s, params, bac);
if (nsec3 != null) return new CEResponse(n, nsec3);
n = new Name(n, 1);
}
return null;
}
/**
* Given a List of nsec3 RRs, find and prove the closest encloser to qname.
*
* @param qname The qname in question.
* @param zonename The name of the zone that the NSEC3 RRs come from.
* @param nsec3s The list of NSEC3s found the this response (already
* verified).
* @param params The NSEC3 parameters found in the response.
* @param bac A pre-allocated comparator. May be null.
* @param proveDoesNotExist If true, then if the closest encloser turns out
* to be qname, then null is returned.
* @return null if the proof isn't completed. Otherwise, return a CEResponse
* object which contains the closest encloser name and the NSEC3
* that matches it.
*/
private static CEResponse proveClosestEncloser(Name qname, Name zonename,
List nsec3s, NSEC3Parameters params, ByteArrayComparator bac,
boolean proveDoesNotExist)
{
CEResponse candidate = findClosestEncloser(qname,
zonename,
nsec3s,
params,
bac);
if (candidate == null)
{
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// st_log.debug("proveClosestEncloser: could not find a "
// + "candidate for the closest encloser.");
return null;
}
if (candidate.closestEncloser.equals(qname))
{
if (proveDoesNotExist)
{
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// st_log.debug("proveClosestEncloser: proved that qname existed!");
return null;
}
// otherwise, we need to nothing else to prove that qname is its own
// closest encloser.
return candidate;
}
// If the closest encloser is actually a delegation, then the response
// should have been a referral. If it is a DNAME, then it should have been
// a DNAME response.
if (candidate.ce_nsec3.hasType(Type.NS)
&& !candidate.ce_nsec3.hasType(Type.SOA))
{
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// st_log.debug("proveClosestEncloser: closest encloser "
// + "was a delegation!");
return null;
}
if (candidate.ce_nsec3.hasType(Type.DNAME))
{
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// st_log.debug("proveClosestEncloser: closest encloser was a DNAME!");
return null;
}
// Otherwise, we need to show that the next closer name is covered.
Name nextClosest = nextClosest(qname, candidate.closestEncloser);
byte[] nc_hash = hash(nextClosest, params);
candidate.nc_nsec3 = findCoveringNSEC3(nc_hash,
zonename,
nsec3s,
params,
bac);
if (candidate.nc_nsec3 == null)
{
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// st_log.debug("Could not find proof that the "
// + "closest encloser was the closest encloser");
return null;
}
return candidate;
}
private static int maxIterations(int baseAlg, int keysize)
{
switch (baseAlg)
{
case DnsSecVerifier.RSA:
if (keysize == 0) return 2500; // the max at 4096
if (keysize > 2048) return 2500;
if (keysize > 1024) return 500;
if (keysize > 0) return 150;
break;
case DnsSecVerifier.DSA:
if (keysize == 0) return 5000; // the max at 2048;
if (keysize > 1024) return 5000;
if (keysize > 0) return 1500;
break;
}
return -1;
}
private static boolean validIterations(NSEC3Parameters nsec3params,
RRset dnskey_rrset, DnsSecVerifier verifier)
{
// for now, we return the maximum iterations based simply on the key
// algorithms that may have been used to sign the NSEC3 RRsets.
int max_iterations = 0;
for (Iterator i = dnskey_rrset.rrs(); i.hasNext();)
{
DNSKEYRecord dnskey = (DNSKEYRecord) i.next();
int baseAlg = verifier.baseAlgorithm(dnskey.getAlgorithm());
int iters = maxIterations(baseAlg, 0);
max_iterations = max_iterations < iters ? iters : max_iterations;
}
if (nsec3params.iterations > max_iterations) return false;
return true;
}
/**
* Determine if all of the NSEC3s in a response are legally ignoreable
* (i.e., their presence should lead to an INSECURE result). Currently, this
* is solely based on iterations.
*
* @param nsec3s The list of NSEC3s. If there is more than one set of NSEC3
* parameters present, this test will not be performed.
* @param dnskey_rrset The set of validating DNSKEYs.
* @param verifier The verifier used to verify the NSEC3 RRsets. This is
* solely used to map algorithm aliases.
* @return true if all of the NSEC3s can be legally ignored, false if not.
*/
public static boolean allNSEC3sIgnoreable(List nsec3s, RRset dnskey_rrset, DnsSecVerifier verifier)
{
NSEC3Parameters params = nsec3Parameters(nsec3s);
if (params == null) return false;
return !validIterations(params, dnskey_rrset, verifier);
}
/**
* Determine if the set of NSEC3 records provided with a response prove NAME
* ERROR. This means that the NSEC3s prove a) the closest encloser exists,
* b) the direct child of the closest encloser towards qname doesn't exist,
* and c) *.closest encloser does not exist.
*
* @param nsec3s The list of NSEC3s.
* @param qname The query name to check against.
* @param zonename This is the name of the zone that the NSEC3s belong to.
* This may be discovered in any number of ways. A good one is to
* use the signerName from the NSEC3 record's RRSIG.
* @return SecurityStatus.SECURE of the Name Error is proven by the NSEC3
* RRs, BOGUS if not, INSECURE if all of the NSEC3s could be validly
* ignored.
*/
public static boolean proveNameError(List nsec3s, Name qname, Name zonename)
{
if (nsec3s == null || nsec3s.size() == 0) return false;
NSEC3Parameters nsec3params = nsec3Parameters(nsec3s);
if (nsec3params == null)
{
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// st_log.debug("Could not find a single set of " +
// "NSEC3 parameters (multiple parameters present).");
return false;
}
ByteArrayComparator bac = new ByteArrayComparator();
// First locate and prove the closest encloser to qname. We will use the
// variant that fails if the closest encloser turns out to be qname.
CEResponse ce = proveClosestEncloser(qname,
zonename,
nsec3s,
nsec3params,
bac,
true);
if (ce == null)
{
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// st_log.debug("proveNameError: failed to prove a closest encloser.");
return false;
}
// At this point, we know that qname does not exist. Now we need to prove
// that the wildcard does not exist.
Name wc = ceWildcard(ce.closestEncloser);
byte[] wc_hash = hash(wc, nsec3params);
NSEC3Record nsec3 = findCoveringNSEC3(wc_hash,
zonename,
nsec3s,
nsec3params,
bac);
if (nsec3 == null)
{
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// st_log.debug("proveNameError: could not prove that the "
// + "applicable wildcard did not exist.");
return false;
}
return true;
}
/**
* Determine if the set of NSEC3 records provided with a response prove NAME
* ERROR when qtype = NSEC3. This is a special case, and (currently anyway)
* it suffices to simply prove that the NSEC3 RRset itself does not exist,
* without proving that no wildcard could have generated it, etc..
*
* @param nsec3s The list of NSEC3s.
* @param qname The query name to check against.
* @param zonename This is the name of the zone that the NSEC3s belong to.
* This may be discovered in any number of ways. A good one is to
* use the signerName from the NSEC3 record's RRSIG.
* @return true of the Name Error is proven by the NSEC3 RRs, false if not.
*/
// public static boolean proveNSEC3NameError(List nsec3s, Name qname,
// Name zonename)
// {
// if (nsec3s == null || nsec3s.size() == 0) return false;
//
// for (Iterator i = nsec3s.iterator(); i.hasNext(); )
// {
// NSEC3Record nsec3 = (NSEC3Record) i.next();
//
// // Convert owner and next into Names.
// Name owner = nsec3.getName();
// Name next = null;
// try
// {
// next = new Name(base32.toString(nsec3.getNext()), zonename);
// }
// catch (TextParseException e)
// {
// continue;
// }
//
// // Now see if qname is covered by the NSEC3.
//
// // normal case, owner < qname < next.
// if (owner.compareTo(next) < 0 && owner.compareTo(qname) < 0 &&
// next.compareTo(qname) > 0)
// {
// st_log.debug("proveNSEC3NameError: found a covering NSEC3: " + nsec3);
// return true;
// }
// // end-of-zone case: next < owner and qname > owner || qname < next.
// if (owner.compareTo(next) > 0 && (owner.compareTo(qname) < 0 ||
// next.compareTo(qname) > 0))
// {
// st_log.debug("proveNSEC3NameError: found a covering NSEC3: " + nsec3);
// return true;
// }
// }
//
// st_log.debug("proveNSEC3NameError: did not find a covering NSEC3");
// return false;
// }
/**
* Determine if the NSEC3s provided in a response prove the NOERROR/NODATA
* status. There are a number of different variants to this:
*
* 1) Normal NODATA -- qname is matched to an NSEC3 record, type is not
* present.
*
* 2) ENT NODATA -- because there must be NSEC3 record for
* empty-non-terminals, this is the same as #1.
*
* 3) NSEC3 ownername NODATA -- qname matched an existing, lone NSEC3
* ownername, but qtype was not NSEC3. NOTE: as of nsec-05, this case no
* longer exists.
*
* 4) Wildcard NODATA -- A wildcard matched the name, but not the type.
*
* 5) Opt-In DS NODATA -- the qname is covered by an opt-in span and qtype ==
* DS. (or maybe some future record with the same parent-side-only property)
*
* @param nsec3s The NSEC3Records to consider.
* @param qname The qname in question.
* @param qtype The qtype in question.
* @param zonename The name of the zone that the NSEC3s came from.
* @return true if the NSEC3s prove the proposition.
*/
public static boolean proveNodata(List nsec3s, Name qname, int qtype,
Name zonename)
{
if (nsec3s == null || nsec3s.size() == 0) return false;
NSEC3Parameters nsec3params = nsec3Parameters(nsec3s);
if (nsec3params == null)
{
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// st_log.debug("could not find a single set of "
// + "NSEC3 parameters (multiple parameters present)");
return false;
}
ByteArrayComparator bac = new ByteArrayComparator();
NSEC3Record nsec3 = findMatchingNSEC3(hash(qname, nsec3params),
zonename,
nsec3s,
nsec3params,
bac);
// Cases 1 & 2.
if (nsec3 != null)
{
if (nsec3.hasType(qtype))
{
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// st_log.debug("proveNodata: Matching NSEC3 proved that type existed!");
return false;
}
if (nsec3.hasType(Type.CNAME))
{
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// st_log.debug("proveNodata: Matching NSEC3 proved "
// + "that a CNAME existed!");
return false;
}
return true;
}
// For cases 3 - 5, we need the proven closest encloser, and it can't
// match qname. Although, at this point, we know that it won't since we
// just checked that.
CEResponse ce = proveClosestEncloser(qname,
zonename,
nsec3s,
nsec3params,
bac,
true);
// At this point, not finding a match or a proven closest encloser is a
// problem.
if (ce == null)
{
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// st_log.debug("proveNodata: did not match qname, "
// + "nor found a proven closest encloser.");
return false;
}
// Case 3: REMOVED
// Case 4:
Name wc = ceWildcard(ce.closestEncloser);
nsec3 = findMatchingNSEC3(hash(wc, nsec3params),
zonename,
nsec3s,
nsec3params,
bac);
if (nsec3 != null)
{
if (nsec3.hasType(qtype))
{
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// st_log.debug("proveNodata: matching wildcard had qtype!");
return false;
}
return true;
}
// Case 5.
if (qtype != Type.DS)
{
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// st_log.debug("proveNodata: could not find matching NSEC3, "
// + "nor matching wildcard, and qtype is not DS -- no more options.");
return false;
}
// We need to make sure that the covering NSEC3 is opt-in.
if (!ce.nc_nsec3.getOptInFlag())
{
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// st_log.debug("proveNodata: covering NSEC3 was not "
// + "opt-in in an opt-in DS NOERROR/NODATA case.");
return false;
}
return true;
}
/**
* Prove that a positive wildcard match was appropriate (no direct match
* RRset).
*
* @param nsec3s The NSEC3 records to work with.
* @param qname The qname that was matched to the wildard
* @param zonename The name of the zone that the NSEC3s come from.
* @param wildcard The purported wildcard that matched.
* @return true if the NSEC3 records prove this case.
*/
public static boolean proveWildcard(List nsec3s, Name qname, Name zonename,
Name wildcard)
{
if (nsec3s == null || nsec3s.size() == 0) return false;
if (qname == null || wildcard == null) return false;
NSEC3Parameters nsec3params = nsec3Parameters(nsec3s);
if (nsec3params == null)
{
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// st_log.debug("couldn't find a single set of NSEC3 parameters (multiple parameters present).");
return false;
}
ByteArrayComparator bac = new ByteArrayComparator();
// We know what the (purported) closest encloser is by just looking at the
// supposed generating wildcard.
CEResponse candidate = new CEResponse(new Name(wildcard, 1), null);
// Now we still need to prove that the original data did not exist.
// Otherwise, we need to show that the next closer name is covered.
Name nextClosest = nextClosest(qname, candidate.closestEncloser);
candidate.nc_nsec3 = findCoveringNSEC3(hash(nextClosest, nsec3params),
zonename,
nsec3s,
nsec3params,
bac);
if (candidate.nc_nsec3 == null)
{
2009-04-19 19:24:49 +00:00
// st_log.debug("proveWildcard: did not find a covering NSEC3 "
// + "that covered the next closer name to " + qname + " from "
// + candidate.closestEncloser + " (derived from wildcard " + wildcard
// + ")");
return false;
}
return true;
}
/**
* Prove that a DS response either had no DS, or wasn't a delegation point.
*
* Fundamentally there are two cases here: normal NODATA and Opt-In NODATA.
*
* @param nsec3s The NSEC3 RRs to examine.
* @param qname The name of the DS in question.
* @param zonename The name of the zone that the NSEC3 RRs come from.
*
* @return SecurityStatus.SECURE if it was proven that there is no DS in a
* secure (i.e., not opt-in) way, SecurityStatus.INSECURE if there
* was no DS in an insecure (i.e., opt-in) way,
* SecurityStatus.INDETERMINATE if it was clear that this wasn't a
* delegation point, and SecurityStatus.BOGUS if the proofs don't
* work out.
*/
public static int proveNoDS(List nsec3s, Name qname, Name zonename)
{
if (nsec3s == null || nsec3s.size() == 0) return SecurityStatus.BOGUS;
NSEC3Parameters nsec3params = nsec3Parameters(nsec3s);
if (nsec3params == null)
{
2009-04-19 19:24:49 +00:00
// st_log.debug("couldn't find a single set of " +
// "NSEC3 parameters (multiple parameters present).");
return SecurityStatus.BOGUS;
}
ByteArrayComparator bac = new ByteArrayComparator();
// Look for a matching NSEC3 to qname -- this is the normal NODATA case.
NSEC3Record nsec3 = findMatchingNSEC3(hash(qname, nsec3params),
zonename,
nsec3s,
nsec3params,
bac);
if (nsec3 != null)
{
// If the matching NSEC3 has the SOA bit set, it is from the wrong zone
// (the child instead of the parent). If it has the DS bit set, then we
// were lied to.
if (nsec3.hasType(Type.SOA) || nsec3.hasType(Type.DS))
{
return SecurityStatus.BOGUS;
}
// If the NSEC3 RR doesn't have the NS bit set, then this wasn't a
// delegation point.
if (!nsec3.hasType(Type.NS)) return SecurityStatus.INDETERMINATE;
// Otherwise, this proves no DS.
return SecurityStatus.SECURE;
}
// Otherwise, we are probably in the opt-in case.
CEResponse ce = proveClosestEncloser(qname,
zonename,
nsec3s,
nsec3params,
bac,
true);
if (ce == null)
{
return SecurityStatus.BOGUS;
}
// If we had the closest encloser proof, then we need to check that the
// covering NSEC3 was opt-in -- the proveClosestEncloser step already
// checked to see if the closest encloser was a delegation or DNAME.
if (ce.nc_nsec3.getOptInFlag())
{
return SecurityStatus.SECURE;
}
return SecurityStatus.BOGUS;
}
}