--- /dev/null
+--- unbound-1.4.17.orig/doc/unbound.conf.5.in
++++ unbound-1.4.17/doc/unbound.conf.5.in
+@@ -519,6 +519,13 @@ authority servers and checks if the repl
+ Disabled by default.
+ This feature is an experimental implementation of draft dns\-0x20.
+ .TP
++.B aaaa\-filter: \fI<yes or no>
++Activate behavior similar to BIND's AAAA-filter.
++This forces the dropping of all AAAA records, unless in the case of
++explicit AAAA queries, when no A records have been confirmed.
++This also causes an additional A query to be sent for each AAAA query.
++This breaks DNSSEC!
++.TP
+ .B private\-address: \fI<IP address or subnet>
+ Give IPv4 of IPv6 addresses or classless subnets. These are addresses
+ on your private network, and are not allowed to be returned for public
+--- unbound-1.4.17.orig/util/config_file.c
++++ unbound-1.4.17/util/config_file.c
+@@ -160,6 +160,7 @@ config_create(void)
+ cfg->harden_below_nxdomain = 0;
+ cfg->harden_referral_path = 0;
+ cfg->use_caps_bits_for_id = 0;
++ cfg->aaaa_filter = 0; /* ASN: default is disabled */
+ cfg->private_address = NULL;
+ cfg->private_domain = NULL;
+ cfg->unwanted_threshold = 0;
+--- unbound-1.4.17.orig/iterator/iter_scrub.c
++++ unbound-1.4.17/iterator/iter_scrub.c
+@@ -580,6 +580,32 @@ static int sanitize_nsec_is_overreach(st
+ }
+
+ /**
++ * ASN: Lookup A records from rrset cache.
++ * @param qinfo: the question originally asked.
++ * @param env: module environment with config and cache.
++ * @param ie: iterator environment with private address data.
++ * @return 0 if no A record found, 1 if A record found.
++ */
++static int
++asn_lookup_a_record_from_cache(struct query_info* qinfo,
++ struct module_env* env, struct iter_env* ie)
++{
++ struct ub_packed_rrset_key* akey;
++
++ /* get cached A records for queried name */
++ akey = rrset_cache_lookup(env->rrset_cache, qinfo->qname,
++ qinfo->qname_len, LDNS_RR_TYPE_A, qinfo->qclass,
++ 0, *env->now, 0);
++ if(akey) { /* we had some. */
++ log_rrset_key(VERB_ALGO, "ASN-AAAA-filter: found A record",
++ akey);
++ lock_rw_unlock(&akey->entry.lock);
++ return 1;
++ }
++ return 0;
++}
++
++/**
+ * Given a response event, remove suspect RRsets from the response.
+ * "Suspect" rrsets are potentially poison. Note that this routine expects
+ * the response to be in a "normalized" state -- that is, all "irrelevant"
+@@ -598,6 +625,7 @@ scrub_sanitize(ldns_buffer* pkt, struct
+ struct query_info* qinfo, uint8_t* zonename, struct module_env* env,
+ struct iter_env* ie)
+ {
++ int found_a_record = 0; /* ASN: do we have a A record? */
+ int del_addi = 0; /* if additional-holding rrsets are deleted, we
+ do not trust the normalized additional-A-AAAA any more */
+ struct rrset_parse* rrset, *prev;
+@@ -633,6 +661,13 @@ scrub_sanitize(ldns_buffer* pkt, struct
+ rrset = rrset->rrset_all_next;
+ }
+
++ /* ASN: Locate any A record we can find */
++ if((ie->aaaa_filter) && (qinfo->qtype == LDNS_RR_TYPE_AAAA)) {
++ found_a_record = asn_lookup_a_record_from_cache(qinfo,
++ env, ie);
++ }
++ /* ASN: End of added code */
++
+ /* At this point, we brutally remove ALL rrsets that aren't
+ * children of the originating zone. The idea here is that,
+ * as far as we know, the server that we contacted is ONLY
+@@ -644,6 +679,24 @@ scrub_sanitize(ldns_buffer* pkt, struct
+ rrset = msg->rrset_first;
+ while(rrset) {
+
++ /* ASN: For AAAA records only... */
++ if((ie->aaaa_filter) && (rrset->type == LDNS_RR_TYPE_AAAA)) {
++ /* ASN: If this is not a AAAA query, then remove AAAA
++ * records, no questions asked. If this IS a AAAA query
++ * then remove AAAA records if we have an A record.
++ * Otherwise, leave things be. */
++ if((qinfo->qtype != LDNS_RR_TYPE_AAAA) ||
++ (found_a_record)) {
++ remove_rrset("ASN-AAAA-filter: removing AAAA "
++ "for record", pkt, msg, prev, &rrset);
++ continue;
++ }
++ log_nametypeclass(VERB_ALGO, "ASN-AAAA-filter: "
++ "keep AAAA for", zonename,
++ LDNS_RR_TYPE_AAAA, qinfo->qclass);
++ }
++ /* ASN: End of added code */
++
+ /* remove private addresses */
+ if( (rrset->type == LDNS_RR_TYPE_A ||
+ rrset->type == LDNS_RR_TYPE_AAAA) &&
+--- unbound-1.4.17.orig/iterator/iterator.c
++++ unbound-1.4.17/iterator/iterator.c
+@@ -1579,6 +1579,53 @@ processDSNSFind(struct module_qstate* qs
+
+ return 0;
+ }
++
++/**
++ * ASN: This event state was added as an intermediary step between
++ * QUERYTARGETS_STATE and the next step, in order to cast a subquery for the
++ * purpose of caching A records for the queried name.
++ *
++ * @param qstate: query state.
++ * @param iq: iterator query state.
++ * @param ie: iterator shared global environment.
++ * @param id: module id.
++ * @return true if the event requires more request processing immediately,
++ * false if not. This state only returns true when it is generating
++ * a SERVFAIL response because the query has hit a dead end.
++ */
++static int
++asn_processQueryAAAA(struct module_qstate* qstate, struct iter_qstate* iq,
++ struct iter_env* ie, int id)
++{
++ struct module_qstate* subq = NULL;
++
++ log_assert(iq->fetch_a_for_aaaa == 0);
++
++ /* flag the query properly in order to not loop */
++ iq->fetch_a_for_aaaa = 1;
++
++ /* re-throw same query, but with a different type */
++ if(!generate_sub_request(iq->qchase.qname,
++ iq->qchase.qname_len, LDNS_RR_TYPE_A,
++ iq->qchase.qclass, qstate, id, iq,
++ INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) {
++ log_nametypeclass(VERB_ALGO, "ASN-AAAA-filter: failed "
++ "preloading of A record for",
++ iq->qchase.qname, LDNS_RR_TYPE_A,
++ iq->qchase.qclass);
++ return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
++ }
++ log_nametypeclass(VERB_ALGO, "ASN-AAAA-filter: "
++ "preloading records in cache for",
++ iq->qchase.qname, LDNS_RR_TYPE_A,
++ iq->qchase.qclass);
++
++ /* set this query as waiting */
++ qstate->ext_state[id] = module_wait_subquery;
++ /* at this point break loop */
++ return 0;
++}
++/* ASN: End of added code */
+
+ /**
+ * This is the request event state where the request will be sent to one of
+@@ -1626,6 +1673,13 @@ processQueryTargets(struct module_qstate
+ return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
+ }
+
++ /* ASN: If we have a AAAA query, then also query for A records */
++ if((ie->aaaa_filter) && (iq->qchase.qtype == LDNS_RR_TYPE_AAAA) &&
++ (iq->fetch_a_for_aaaa == 0)) {
++ return next_state(iq, ASN_FETCH_A_FOR_AAAA_STATE);
++ }
++ /* ASN: End of added code */
++
+ /* Make sure we have a delegation point, otherwise priming failed
+ * or another failure occurred */
+ if(!iq->dp) {
+@@ -2568,6 +2622,62 @@ processFinished(struct module_qstate* qs
+ return 0;
+ }
+
++/**
++ * ASN: Do final processing on responses to A queries originated from AAAA
++ * queries. Events reach this state after the iterative resolution algorithm
++ * terminates.
++ * This is required down the road to decide whether to scrub AAAA records
++ * from the results or not.
++ *
++ * @param qstate: query state.
++ * @param id: module id.
++ * @param forq: super query state.
++ */
++static void
++asn_processAAAAResponse(struct module_qstate* qstate, int id,
++ struct module_qstate* super)
++{
++ struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
++ struct iter_qstate* super_iq = (struct iter_qstate*)super->minfo[id];
++ struct ub_packed_rrset_key* rrset;
++ struct delegpt_ns* dpns = NULL;
++ int error = (qstate->return_rcode != LDNS_RCODE_NOERROR);
++
++ log_assert(super_iq->fetch_a_for_aaaa > 0);
++
++ /* let super go to evaluation of targets after this */
++ super_iq->state = QUERYTARGETS_STATE;
++
++ log_query_info(VERB_ALGO, "ASN-AAAA-filter: processAAAAResponse",
++ &qstate->qinfo);
++ log_query_info(VERB_ALGO, "ASN-AAAA-filter: processAAAAResponse super",
++ &super->qinfo);
++
++ if(super_iq->dp)
++ dpns = delegpt_find_ns(super_iq->dp,
++ qstate->qinfo.qname, qstate->qinfo.qname_len);
++ if (!dpns) {
++ /* not interested */
++ verbose(VERB_ALGO, "ASN-AAAA-filter: subq: %s, but parent not "
++ "interested%s", (error ? "error, but" : "success"),
++ (super_iq->dp ? "anymore" : " (was reset)"));
++ log_query_info(VERB_ALGO, "ASN-AAAA-filter: superq", &super->qinfo);
++ if(super_iq->dp && error)
++ delegpt_log(VERB_ALGO, super_iq->dp);
++ return;
++ } else if (error) {
++ verbose(VERB_ALGO, "ASN-AAAA-filter: mark as failed, "
++ "and go to target query.");
++ /* see if the failure did get (parent-lame) info */
++ if(!cache_fill_missing(super->env,
++ super_iq->qchase.qclass, super->region,
++ super_iq->dp))
++ log_err("ASN-AAAA-filter: out of memory adding missing");
++ dpns->resolved = 1; /* mark as failed */
++ }
++}
++/* ASN: End of added code */
++
+ /*
+ * Return priming query results to interestes super querystates.
+ *
+@@ -2587,6 +2697,9 @@ iter_inform_super(struct module_qstate*
+ else if(super->qinfo.qtype == LDNS_RR_TYPE_DS && ((struct iter_qstate*)
+ super->minfo[id])->state == DSNS_FIND_STATE)
+ processDSNSResponse(qstate, id, super);
++ else if (super->qinfo.qtype == LDNS_RR_TYPE_AAAA && ((struct iter_qstate*)
++ super->minfo[id])->state == ASN_FETCH_A_FOR_AAAA_STATE)
++ asn_processAAAAResponse(qstate, id, super);
+ else if(qstate->return_rcode != LDNS_RCODE_NOERROR)
+ error_supers(qstate, id, super);
+ else if(qstate->is_priming)
+@@ -2624,6 +2737,9 @@ iter_handle(struct module_qstate* qstate
+ case INIT_REQUEST_3_STATE:
+ cont = processInitRequest3(qstate, iq, id);
+ break;
++ case ASN_FETCH_A_FOR_AAAA_STATE:
++ cont = asn_processQueryAAAA(qstate, iq, ie, id);
++ break;
+ case QUERYTARGETS_STATE:
+ cont = processQueryTargets(qstate, iq, ie, id);
+ break;
+@@ -2863,6 +2979,8 @@ iter_state_to_string(enum iter_state sta
+ return "INIT REQUEST STATE (stage 2)";
+ case INIT_REQUEST_3_STATE:
+ return "INIT REQUEST STATE (stage 3)";
++ case ASN_FETCH_A_FOR_AAAA_STATE:
++ return "ASN_FETCH_A_FOR_AAAA_STATE";
+ case QUERYTARGETS_STATE :
+ return "QUERY TARGETS STATE";
+ case PRIME_RESP_STATE :
+@@ -2887,6 +3005,7 @@ iter_state_is_responsestate(enum iter_st
+ case INIT_REQUEST_STATE :
+ case INIT_REQUEST_2_STATE :
+ case INIT_REQUEST_3_STATE :
++ case ASN_FETCH_A_FOR_AAAA_STATE :
+ case QUERYTARGETS_STATE :
+ case COLLECT_CLASS_STATE :
+ return 0;
+--- unbound-1.4.17.orig/iterator/iter_utils.c
++++ unbound-1.4.17/iterator/iter_utils.c
+@@ -128,6 +128,7 @@ iter_apply_cfg(struct iter_env* iter_env
+ }
+ iter_env->supports_ipv6 = cfg->do_ip6;
+ iter_env->supports_ipv4 = cfg->do_ip4;
++ iter_env->aaaa_filter = cfg->aaaa_filter;
+ return 1;
+ }
+
+--- unbound-1.4.17.orig/iterator/iterator.h
++++ unbound-1.4.17/iterator/iterator.h
+@@ -110,6 +110,9 @@ struct iter_env {
+ * array of max_dependency_depth+1 size.
+ */
+ int* target_fetch_policy;
++
++ /** ASN: AAAA-filter flag */
++ int aaaa_filter;
+ };
+
+ /**
+@@ -135,6 +138,14 @@ enum iter_state {
+ INIT_REQUEST_3_STATE,
+
+ /**
++ * This state is responsible for intercepting AAAA queries,
++ * and launch a A subquery on the same target, to populate the
++ * cache with A records, so the AAAA filter scrubbing logic can
++ * work.
++ */
++ ASN_FETCH_A_FOR_AAAA_STATE,
++
++ /**
+ * Each time a delegation point changes for a given query or a
+ * query times out and/or wakes up, this state is (re)visited.
+ * This state is reponsible for iterating through a list of
+@@ -309,6 +320,13 @@ struct iter_qstate {
+ */
+ int refetch_glue;
+
++ /**
++ * ASN: This is a flag that, if true, means that this query is
++ * for fetching A records to populate cache and determine if we must
++ * return AAAA records or not.
++ */
++ int fetch_a_for_aaaa;
++
+ /** list of pending queries to authoritative servers. */
+ struct outbound_list outlist;
+ };
+--- unbound-1.4.17.orig/util/config_file.h
++++ unbound-1.4.17/util/config_file.h
+@@ -169,6 +169,8 @@ struct config_file {
+ int harden_referral_path;
+ /** use 0x20 bits in query as random ID bits */
+ int use_caps_bits_for_id;
++ /** ASN: enable AAAA filter? */
++ int aaaa_filter;
+ /** strip away these private addrs from answers, no DNS Rebinding */
+ struct config_strlist* private_address;
+ /** allow domain (and subdomains) to use private address space */
+--- unbound-1.4.17.orig/util/configlexer.lex
++++ unbound-1.4.17/util/configlexer.lex
+@@ -177,6 +177,7 @@ harden-below-nxdomain{COLON} { YDVAR(1,
+ harden-referral-path{COLON} { YDVAR(1, VAR_HARDEN_REFERRAL_PATH) }
+ use-caps-for-id{COLON} { YDVAR(1, VAR_USE_CAPS_FOR_ID) }
+ unwanted-reply-threshold{COLON} { YDVAR(1, VAR_UNWANTED_REPLY_THRESHOLD) }
++aaaa-filter{COLON} { YDVAR(1, VAR_AAAA_FILTER) }
+ private-address{COLON} { YDVAR(1, VAR_PRIVATE_ADDRESS) }
+ private-domain{COLON} { YDVAR(1, VAR_PRIVATE_DOMAIN) }
+ prefetch-key{COLON} { YDVAR(1, VAR_PREFETCH_KEY) }
+--- unbound-1.4.17.orig/util/configparser.y
++++ unbound-1.4.17/util/configparser.y
+@@ -92,6 +92,7 @@ extern struct config_parser_state* cfg_p
+ %token VAR_STATISTICS_CUMULATIVE VAR_OUTGOING_PORT_PERMIT
+ %token VAR_OUTGOING_PORT_AVOID VAR_DLV_ANCHOR_FILE VAR_DLV_ANCHOR
+ %token VAR_NEG_CACHE_SIZE VAR_HARDEN_REFERRAL_PATH VAR_PRIVATE_ADDRESS
++%token VAR_AAAA_FILTER
+ %token VAR_PRIVATE_DOMAIN VAR_REMOTE_CONTROL VAR_CONTROL_ENABLE
+ %token VAR_CONTROL_INTERFACE VAR_CONTROL_PORT VAR_SERVER_KEY_FILE
+ %token VAR_SERVER_CERT_FILE VAR_CONTROL_KEY_FILE VAR_CONTROL_CERT_FILE
+@@ -151,6 +152,7 @@ content_server: server_num_threads | ser
+ server_dlv_anchor_file | server_dlv_anchor | server_neg_cache_size |
+ server_harden_referral_path | server_private_address |
+ server_private_domain | server_extended_statistics |
++ server_aaaa_filter |
+ server_local_data_ptr | server_jostle_timeout |
+ server_unwanted_reply_threshold | server_log_time_ascii |
+ server_domain_insecure | server_val_sig_skew_min |
+@@ -802,6 +803,15 @@ server_use_caps_for_id: VAR_USE_CAPS_FOR
+ free($2);
+ }
+ ;
++server_aaaa_filter: VAR_AAAA_FILTER STRING_ARG
++ {
++ OUTYY(("P(server_aaaa_filter:%s)\n", $2));
++ if(strcmp($2, "yes") != 0 && strcmp($2, "no") != 0)
++ yyerror("expected yes or no.");
++ else cfg_parser->cfg->aaaa_filter = (strcmp($2, "yes")==0);
++ free($2);
++ }
++ ;
+ server_private_address: VAR_PRIVATE_ADDRESS STRING_ARG
+ {
+ OUTYY(("P(server_private_address:%s)\n", $2));
+--- unbound-1.4.17.orig/pythonmod/interface.i
++++ unbound-1.4.17/pythonmod/interface.i
+@@ -626,6 +626,7 @@ struct config_file {
+ int harden_dnssec_stripped;
+ int harden_referral_path;
+ int use_caps_bits_for_id;
++ int aaaa_filter; /* ASN */
+ struct config_strlist* private_address;
+ struct config_strlist* private_domain;
+ size_t unwanted_threshold;
projects / thirdparty / unbound.git / commitdiff
