/*
 * util/data/msgreply.c - store message and reply data. 
 *
 * Copyright (c) 2007, NLnet Labs. All rights reserved.
 *
 * This software is open source.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * 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.
 * 
 * Neither the name of the NLNET LABS nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "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 COPYRIGHT
 * HOLDER OR CONTRIBUTORS 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.
 */

/**
 * \file
 *
 * This file contains a data structure to store a message and its reply.
 */

#include "config.h"
#include "util/data/msgreply.h"
#include "util/storage/lookup3.h"
#include "util/log.h"
#include "util/alloc.h"
#include "util/netevent.h"
#include "util/net_help.h"
#include "util/data/dname.h"
#include "util/regional.h"
#include "util/data/msgparse.h"
#include "util/data/msgencode.h"
#include "sldns/sbuffer.h"
#include "sldns/wire2str.h"
#include "util/module.h"
#include "util/fptr_wlist.h"

/** MAX TTL default for messages and rrsets */
time_t MAX_TTL = 3600 * 24 * 10; /* ten days */
/** MIN TTL default for messages and rrsets */
time_t MIN_TTL = 0;
/** MAX Negative TTL, for SOA records in authority section */
time_t MAX_NEG_TTL = 3600; /* one hour */
/** MIN Negative TTL, for SOA records in authority section */
time_t MIN_NEG_TTL = 0;
/** If we serve expired entries and prefetch them */
int SERVE_EXPIRED = 0;
/** Time to serve records after expiration */
time_t SERVE_EXPIRED_TTL = 86400;
/** Reset serve expired TTL after failed update attempt */
time_t SERVE_EXPIRED_TTL_RESET = 0;
/** TTL to use for expired records */
time_t SERVE_EXPIRED_REPLY_TTL = 30;
/** If we serve the original TTL or decrementing TTLs */
int SERVE_ORIGINAL_TTL = 0;

/** allocate qinfo, return 0 on error */
static int
parse_create_qinfo(sldns_buffer* pkt, struct msg_parse* msg, 
        struct query_info* qinf, struct regional* region)
{
        if(msg->qname) {
                if(region)
                        qinf->qname = (uint8_t*)regional_alloc(region, 
                                msg->qname_len);
                else    qinf->qname = (uint8_t*)malloc(msg->qname_len);
                if(!qinf->qname) return 0;
                dname_pkt_copy(pkt, qinf->qname, msg->qname);
        } else  qinf->qname = 0;
        qinf->qname_len = msg->qname_len;
        qinf->qtype = msg->qtype;
        qinf->qclass = msg->qclass;
        qinf->local_alias = NULL;
        return 1;
}

/** constructor for replyinfo */
struct reply_info*
construct_reply_info_base(struct regional* region, uint16_t flags, size_t qd,
        time_t ttl, time_t prettl, time_t expttl, time_t norecttl, size_t an,
        size_t ns, size_t ar, size_t total, enum sec_status sec,
        sldns_ede_code reason_bogus)
{
        struct reply_info* rep;
        /* rrset_count-1 because the first ref is part of the struct. */
        size_t s = sizeof(struct reply_info) - sizeof(struct rrset_ref) +
                sizeof(struct ub_packed_rrset_key*) * total;
        if(total >= RR_COUNT_MAX) return NULL; /* sanity check on numRRS*/
        if(region)
                rep = (struct reply_info*)regional_alloc(region, s);
        else    rep = (struct reply_info*)malloc(s + 
                        sizeof(struct rrset_ref) * (total));
        if(!rep) 
                return NULL;
        rep->flags = flags;
        rep->qdcount = qd;
        rep->ttl = ttl;
        rep->prefetch_ttl = prettl;
        rep->serve_expired_ttl = expttl;
        rep->serve_expired_norec_ttl = norecttl;
        rep->an_numrrsets = an;
        rep->ns_numrrsets = ns;
        rep->ar_numrrsets = ar;
        rep->rrset_count = total;
        rep->security = sec;
        rep->reason_bogus = reason_bogus;
        /* this is only allocated and used for caching on copy */
        rep->reason_bogus_str = NULL;
        rep->authoritative = 0;
        /* array starts after the refs */
        if(region)
                rep->rrsets = (struct ub_packed_rrset_key**)&(rep->ref[0]);
        else    rep->rrsets = (struct ub_packed_rrset_key**)&(rep->ref[total]);
        /* zero the arrays to assist cleanup in case of malloc failure */
        memset( rep->rrsets, 0, sizeof(struct ub_packed_rrset_key*) * total);
        if(!region)
                memset( &rep->ref[0], 0, sizeof(struct rrset_ref) * total);
        return rep;
}

/** allocate replyinfo, return 0 on error */
static int
parse_create_repinfo(struct msg_parse* msg, struct reply_info** rep,
        struct regional* region)
{
        *rep = construct_reply_info_base(region, msg->flags, msg->qdcount, 0,
                0, 0, 0, msg->an_rrsets, msg->ns_rrsets, msg->ar_rrsets,
                msg->rrset_count, sec_status_unchecked, LDNS_EDE_NONE);
        if(!*rep)
                return 0;
        return 1;
}

int
reply_info_alloc_rrset_keys(struct reply_info* rep, struct alloc_cache* alloc,
        struct regional* region)
{
        size_t i;
        for(i=0; i<rep->rrset_count; i++) {
                if(region) {
                        rep->rrsets[i] = (struct ub_packed_rrset_key*)
                                regional_alloc(region, 
                                sizeof(struct ub_packed_rrset_key));
                        if(rep->rrsets[i]) {
                                memset(rep->rrsets[i], 0, 
                                        sizeof(struct ub_packed_rrset_key));
                                rep->rrsets[i]->entry.key = rep->rrsets[i];
                        }
                }
                else    rep->rrsets[i] = alloc_special_obtain(alloc);
                if(!rep->rrsets[i])
                        return 0;
                rep->rrsets[i]->entry.data = NULL;
        }
        return 1;
}

int
reply_info_can_answer_expired(struct reply_info* rep, time_t timenow)
{
        log_assert(rep->ttl < timenow);
        /* Really expired */
        if(SERVE_EXPIRED_TTL && rep->serve_expired_ttl < timenow) return 0;
        /* Ignore expired failure answers */
        if(FLAGS_GET_RCODE(rep->flags) != LDNS_RCODE_NOERROR &&
                FLAGS_GET_RCODE(rep->flags) != LDNS_RCODE_NXDOMAIN &&
                FLAGS_GET_RCODE(rep->flags) != LDNS_RCODE_YXDOMAIN) return 0;
        return 1;
}

int reply_info_could_use_expired(struct reply_info* rep, time_t timenow)
{
        log_assert(rep->ttl < timenow);
        /* Really expired */
        if(SERVE_EXPIRED_TTL && rep->serve_expired_ttl < timenow &&
                !SERVE_EXPIRED_TTL_RESET) return 0;
        /* Ignore expired failure answers */
        if(FLAGS_GET_RCODE(rep->flags) != LDNS_RCODE_NOERROR &&
                FLAGS_GET_RCODE(rep->flags) != LDNS_RCODE_NXDOMAIN &&
                FLAGS_GET_RCODE(rep->flags) != LDNS_RCODE_YXDOMAIN) return 0;
        return 1;
}

struct reply_info *
make_new_reply_info(const struct reply_info* rep, struct regional* region,
        size_t an_numrrsets, size_t copy_rrsets)
{
        struct reply_info* new_rep;
        size_t i;

        /* create a base struct.  we specify 'insecure' security status as
         * the modified response won't be DNSSEC-valid.  In our faked response
         * the authority and additional sections will be empty (except possible
         * EDNS0 OPT RR in the additional section appended on sending it out),
         * so the total number of RRsets is an_numrrsets. */
        new_rep = construct_reply_info_base(region, rep->flags,
                rep->qdcount, rep->ttl, rep->prefetch_ttl,
                rep->serve_expired_ttl, rep->serve_expired_norec_ttl,
                an_numrrsets, 0, 0, an_numrrsets,
                sec_status_insecure, LDNS_EDE_NONE);
        if(!new_rep)
                return NULL;
        if(!reply_info_alloc_rrset_keys(new_rep, NULL, region))
                return NULL;
        for(i=0; i<copy_rrsets; i++)
                new_rep->rrsets[i] = rep->rrsets[i];

        return new_rep;
}

/** find the minimumttl in the rdata of SOA record */
static time_t
soa_find_minttl(struct rr_parse* rr)
{
        uint16_t rlen = sldns_read_uint16(rr->ttl_data+4);
        if(rlen < 20)
                return 0; /* rdata too small for SOA (dname, dname, 5*32bit) */
        /* minimum TTL is the last 32bit value in the rdata of the record */
        /* at position ttl_data + 4(ttl) + 2(rdatalen) + rdatalen - 4(timeval)*/
        return (time_t)sldns_read_uint32(rr->ttl_data+6+rlen-4);
}

/** do the rdata copy */
static int
rdata_copy(sldns_buffer* pkt, struct packed_rrset_data* data, uint8_t* to, 
        struct rr_parse* rr, time_t* rr_ttl, uint16_t type,
        sldns_pkt_section section)
{
        uint16_t pkt_len;
        const sldns_rr_descriptor* desc;

        *rr_ttl = sldns_read_uint32(rr->ttl_data);
        /* RFC 2181 Section 8. if msb of ttl is set treat as if zero. */
        if((*rr_ttl & 0x80000000U))
                *rr_ttl = 0;
        if(type == LDNS_RR_TYPE_SOA && section == LDNS_SECTION_AUTHORITY) {
                /* negative response. see if TTL of SOA record larger than the
                 * minimum-ttl in the rdata of the SOA record */
                if(*rr_ttl > soa_find_minttl(rr)) *rr_ttl = soa_find_minttl(rr);
                if(!SERVE_ORIGINAL_TTL) {
                        /* If MIN_NEG_TTL is configured skip setting MIN_TTL */
                        if(MIN_NEG_TTL <= 0 && *rr_ttl < MIN_TTL) {
                                *rr_ttl = MIN_TTL;
                        }
                        if(*rr_ttl > MAX_TTL) *rr_ttl = MAX_TTL;
                }
                /* MAX_NEG_TTL overrides the min and max ttl of everything
                 * else; it is for a more specific record */
                if(*rr_ttl > MAX_NEG_TTL) *rr_ttl = MAX_NEG_TTL;
                /* MIN_NEG_TTL overrides the min and max ttl of everything
                 * else if configured; it is for a more specific record */
                if(MIN_NEG_TTL > 0 && *rr_ttl < MIN_NEG_TTL) {
                        *rr_ttl = MIN_NEG_TTL;
                }
        } else if(!SERVE_ORIGINAL_TTL) {
                if(*rr_ttl < MIN_TTL) *rr_ttl = MIN_TTL;
                if(*rr_ttl > MAX_TTL) *rr_ttl = MAX_TTL;
        }
        if(*rr_ttl < data->ttl)
                data->ttl = *rr_ttl;

        if(rr->outside_packet) {
                /* uncompressed already, only needs copy */
                memmove(to, rr->ttl_data+sizeof(uint32_t), rr->size);
                return 1;
        }

        sldns_buffer_set_position(pkt, (size_t)
                (rr->ttl_data - sldns_buffer_begin(pkt) + sizeof(uint32_t)));
        /* insert decompressed size into rdata len stored in memory */
        /* -2 because rdatalen bytes are not included. */
        pkt_len = htons(rr->size - 2);
        memmove(to, &pkt_len, sizeof(uint16_t));
        to += 2;
        /* read packet rdata len */
        pkt_len = sldns_buffer_read_u16(pkt);
        if(sldns_buffer_remaining(pkt) < pkt_len)
                return 0;
        desc = sldns_rr_descript(type);
        if(pkt_len > 0 && desc && desc->_dname_count > 0) {
                int count = (int)desc->_dname_count;
                int rdf = 0;
                size_t len;
                size_t oldpos;
                /* decompress dnames. */
                while(pkt_len > 0 && count) {
                        switch(desc->_wireformat[rdf]) {
                        case LDNS_RDF_TYPE_DNAME:
                                oldpos = sldns_buffer_position(pkt);
                                dname_pkt_copy(pkt, to, 
                                        sldns_buffer_current(pkt));
                                to += pkt_dname_len(pkt);
                                pkt_len -= sldns_buffer_position(pkt)-oldpos;
                                count--;
                                len = 0;
                                break;
                        case LDNS_RDF_TYPE_STR:
                                len = sldns_buffer_current(pkt)[0] + 1;
                                break;
                        default:
                                len = get_rdf_size(desc->_wireformat[rdf]);
                                break;
                        }
                        if(len) {
                                log_assert(len <= pkt_len);
                                memmove(to, sldns_buffer_current(pkt), len);
                                to += len;
                                sldns_buffer_skip(pkt, (ssize_t)len);
                                pkt_len -= len;
                        }
                        rdf++;
                }
        }
        /* copy remaining rdata */
        if(pkt_len >  0)
                memmove(to, sldns_buffer_current(pkt), pkt_len);
        
        return 1;
}

/** copy over the data into packed rrset */
static int
parse_rr_copy(sldns_buffer* pkt, struct rrset_parse* pset, 
        struct packed_rrset_data* data)
{
        size_t i;
        struct rr_parse* rr = pset->rr_first;
        uint8_t* nextrdata;
        size_t total = pset->rr_count + pset->rrsig_count;
        data->ttl = MAX_TTL;
        data->count = pset->rr_count;
        data->rrsig_count = pset->rrsig_count;
        data->trust = rrset_trust_none;
        data->security = sec_status_unchecked;
        /* layout: struct - rr_len - rr_data - rr_ttl - rdata - rrsig */
        data->rr_len = (size_t*)((uint8_t*)data + 
                sizeof(struct packed_rrset_data));
        data->rr_data = (uint8_t**)&(data->rr_len[total]);
        data->rr_ttl = (time_t*)&(data->rr_data[total]);
        nextrdata = (uint8_t*)&(data->rr_ttl[total]);
        for(i=0; i<data->count; i++) {
                data->rr_len[i] = rr->size;
                data->rr_data[i] = nextrdata;
                nextrdata += rr->size;
                if(!rdata_copy(pkt, data, data->rr_data[i], rr, 
                        &data->rr_ttl[i], pset->type, pset->section))
                        return 0;
                rr = rr->next;
        }
        /* if rrsig, its rdata is at nextrdata */
        rr = pset->rrsig_first;
        for(i=data->count; i<total; i++) {
                data->rr_len[i] = rr->size;
                data->rr_data[i] = nextrdata;
                nextrdata += rr->size;
                if(!rdata_copy(pkt, data, data->rr_data[i], rr, 
                        &data->rr_ttl[i], LDNS_RR_TYPE_RRSIG, pset->section))
                        return 0;
                rr = rr->next;
        }
        return 1;
}

/** create rrset return 0 on failure */
static int
parse_create_rrset(sldns_buffer* pkt, struct rrset_parse* pset,
        struct packed_rrset_data** data, struct regional* region)
{
        /* allocate */
        size_t s;
        if(pset->rr_count > RR_COUNT_MAX || pset->rrsig_count > RR_COUNT_MAX ||
                pset->size > RR_COUNT_MAX)
                return 0; /* protect against integer overflow */
        s = sizeof(struct packed_rrset_data) + 
                (pset->rr_count + pset->rrsig_count) * 
                (sizeof(size_t)+sizeof(uint8_t*)+sizeof(time_t)) + 
                pset->size;
        if(region)
                *data = regional_alloc_zero(region, s);
        else    *data = calloc(1, s);
        if(!*data)
                return 0;
        /* copy & decompress */
        if(!parse_rr_copy(pkt, pset, *data)) {
                if(!region) {
                        free(*data);
                        *data = NULL;
                }
                return 0;
        }
        return 1;
}

/** get trust value for rrset */
static enum rrset_trust
get_rrset_trust(struct msg_parse* msg, struct rrset_parse* rrset)
{
        uint16_t AA = msg->flags & BIT_AA;
        if(rrset->section == LDNS_SECTION_ANSWER) {
                if(AA) {
                        /* RFC2181 says remainder of CNAME chain is nonauth*/
                        if(msg->rrset_first && 
                                msg->rrset_first->section==LDNS_SECTION_ANSWER
                                && msg->rrset_first->type==LDNS_RR_TYPE_CNAME){
                                if(rrset == msg->rrset_first)
                                        return rrset_trust_ans_AA;
                                else    return rrset_trust_ans_noAA;
                        }
                        if(msg->rrset_first && 
                                msg->rrset_first->section==LDNS_SECTION_ANSWER
                                && msg->rrset_first->type==LDNS_RR_TYPE_DNAME){
                                if(rrset == msg->rrset_first ||
                                   rrset == msg->rrset_first->rrset_all_next)
                                        return rrset_trust_ans_AA;
                                else    return rrset_trust_ans_noAA;
                        }
                        return rrset_trust_ans_AA;
                }
                else    return rrset_trust_ans_noAA;
        } else if(rrset->section == LDNS_SECTION_AUTHORITY) {
                if(AA)  return rrset_trust_auth_AA;
                else    return rrset_trust_auth_noAA;
        } else {
                /* addit section */
                if(AA)  return rrset_trust_add_AA;
                else    return rrset_trust_add_noAA;
        }
        /* NOTREACHED */
        return rrset_trust_none;
}

int
parse_copy_decompress_rrset(sldns_buffer* pkt, struct msg_parse* msg,
        struct rrset_parse *pset, struct regional* region, 
        struct ub_packed_rrset_key* pk)
{
        struct packed_rrset_data* data;
        pk->rk.flags = pset->flags;
        pk->rk.dname_len = pset->dname_len;
        if(region)
                pk->rk.dname = (uint8_t*)regional_alloc(
                        region, pset->dname_len);
        else    pk->rk.dname = 
                        (uint8_t*)malloc(pset->dname_len);
        if(!pk->rk.dname)
                return 0;
        /** copy & decompress dname */
        dname_pkt_copy(pkt, pk->rk.dname, pset->dname);
        /** copy over type and class */
        pk->rk.type = htons(pset->type);
        pk->rk.rrset_class = pset->rrset_class;
        /** read data part. */
        if(!parse_create_rrset(pkt, pset, &data, region)) {
                if(!region) {
                        free(pk->rk.dname);
                        pk->rk.dname = NULL;
                }
                return 0;
        }
        pk->entry.data = (void*)data;
        pk->entry.key = (void*)pk;
        pk->entry.hash = pset->hash;
        data->trust = get_rrset_trust(msg, pset);
        return 1;
}

/** 
 * Copy and decompress rrs
 * @param pkt: the packet for compression pointer resolution.
 * @param msg: the parsed message
 * @param rep: reply info to put rrs into.
 * @param region: if not NULL, used for allocation.
 * @return 0 on failure.
 */
static int
parse_copy_decompress(sldns_buffer* pkt, struct msg_parse* msg,
        struct reply_info* rep, struct regional* region)
{
        size_t i;
        struct rrset_parse *pset = msg->rrset_first;
        struct packed_rrset_data* data;
        log_assert(rep);
        rep->ttl = MAX_TTL;
        rep->security = sec_status_unchecked;
        if(rep->rrset_count == 0)
                rep->ttl = NORR_TTL;

        for(i=0; i<rep->rrset_count; i++) {
                if(!parse_copy_decompress_rrset(pkt, msg, pset, region,
                        rep->rrsets[i]))
                        return 0;
                data = (struct packed_rrset_data*)rep->rrsets[i]->entry.data;
                if(data->ttl < rep->ttl)
                        rep->ttl = data->ttl;

                pset = pset->rrset_all_next;
        }
        rep->prefetch_ttl = PREFETCH_TTL_CALC(rep->ttl);
        rep->serve_expired_ttl = rep->ttl + SERVE_EXPIRED_TTL;
        /* rep->serve_expired_norec_ttl should stay at 0 */
        log_assert(rep->serve_expired_norec_ttl == 0);
        return 1;
}

int 
parse_create_msg(sldns_buffer* pkt, struct msg_parse* msg,
        struct alloc_cache* alloc, struct query_info* qinf, 
        struct reply_info** rep, struct regional* region)
{
        log_assert(pkt && msg);
        if(!parse_create_qinfo(pkt, msg, qinf, region))
                return 0;
        if(!parse_create_repinfo(msg, rep, region))
                return 0;
        if(!reply_info_alloc_rrset_keys(*rep, alloc, region)) {
                if(!region) reply_info_parsedelete(*rep, alloc);
                return 0;
        }
        if(!parse_copy_decompress(pkt, msg, *rep, region)) {
                if(!region) reply_info_parsedelete(*rep, alloc);
                return 0;
        }
        return 1;
}

int reply_info_parse(sldns_buffer* pkt, struct alloc_cache* alloc,
        struct query_info* qinf, struct reply_info** rep, 
        struct regional* region, struct edns_data* edns)
{
        /* use scratch pad region-allocator during parsing. */
        struct msg_parse* msg;
        int ret;
        
        qinf->qname = NULL;
        qinf->local_alias = NULL;
        *rep = NULL;
        if(!(msg = regional_alloc(region, sizeof(*msg)))) {
                return LDNS_RCODE_SERVFAIL;
        }
        memset(msg, 0, sizeof(*msg));
        
        sldns_buffer_set_position(pkt, 0);
        if((ret = parse_packet(pkt, msg, region)) != 0) {
                return ret;
        }
        if((ret = parse_extract_edns_from_response_msg(msg, edns, region)) != 0)
                return ret;

        /* parse OK, allocate return structures */
        /* this also performs dname decompression */
        if(!parse_create_msg(pkt, msg, alloc, qinf, rep, NULL)) {
                query_info_clear(qinf);
                *rep = NULL;
                return LDNS_RCODE_SERVFAIL;
        }
        return 0;
}

/** helper compare function to sort in lock order */
static int
reply_info_sortref_cmp(const void* a, const void* b)
{
        struct rrset_ref* x = (struct rrset_ref*)a;
        struct rrset_ref* y = (struct rrset_ref*)b;
        if(x->key < y->key) return -1;
        if(x->key > y->key) return 1;
        return 0;
}

void 
reply_info_sortref(struct reply_info* rep)
{
        qsort(&rep->ref[0], rep->rrset_count, sizeof(struct rrset_ref),
                reply_info_sortref_cmp);
}

void 
reply_info_set_ttls(struct reply_info* rep, time_t timenow)
{
        size_t i, j;
        rep->ttl += timenow;
        rep->prefetch_ttl += timenow;
        rep->serve_expired_ttl += timenow;
        /* Don't set rep->serve_expired_norec_ttl; this should only be set
         * on cached records when encountering an error */
        log_assert(rep->serve_expired_norec_ttl == 0);
        for(i=0; i<rep->rrset_count; i++) {
                struct packed_rrset_data* data = (struct packed_rrset_data*)
                        rep->ref[i].key->entry.data;
                if(i>0 && rep->ref[i].key == rep->ref[i-1].key)
                        continue;
                data->ttl += timenow;
                for(j=0; j<data->count + data->rrsig_count; j++) {
                        data->rr_ttl[j] += timenow;
                }
                data->ttl_add = timenow;
        }
}

void 
reply_info_parsedelete(struct reply_info* rep, struct alloc_cache* alloc)
{
        size_t i;
        if(!rep) 
                return;
        /* no need to lock, since not shared in hashtables. */
        for(i=0; i<rep->rrset_count; i++) {
                ub_packed_rrset_parsedelete(rep->rrsets[i], alloc);
        }
        if(rep->reason_bogus_str) {
                free(rep->reason_bogus_str);
                rep->reason_bogus_str = NULL;
        }
        free(rep);
}

int 
query_info_parse(struct query_info* m, sldns_buffer* query)
{
        uint8_t* q = sldns_buffer_begin(query);
        /* minimum size: header + \0 + qtype + qclass */
        if(sldns_buffer_limit(query) < LDNS_HEADER_SIZE + 5)
                return 0;
        if((LDNS_OPCODE_WIRE(q) != LDNS_PACKET_QUERY && LDNS_OPCODE_WIRE(q) !=
                LDNS_PACKET_NOTIFY) || LDNS_QDCOUNT(q) != 1 ||
                sldns_buffer_position(query) != 0)
                return 0;
        sldns_buffer_skip(query, LDNS_HEADER_SIZE);
        m->qname = sldns_buffer_current(query);
        if((m->qname_len = query_dname_len(query)) == 0)
                return 0; /* parse error */
        if(sldns_buffer_remaining(query) < 4)
                return 0; /* need qtype, qclass */
        m->qtype = sldns_buffer_read_u16(query);
        m->qclass = sldns_buffer_read_u16(query);
        m->local_alias = NULL;
        return 1;
}

/** tiny subroutine for msgreply_compare */
#define COMPARE_IT(x, y) \
        if( (x) < (y) ) return -1; \
        else if( (x) > (y) ) return +1; \
        log_assert( (x) == (y) );

int 
query_info_compare(void* m1, void* m2)
{
        struct query_info* msg1 = (struct query_info*)m1;
        struct query_info* msg2 = (struct query_info*)m2;
        int mc;
        /* from most different to least different for speed */
        COMPARE_IT(msg1->qtype, msg2->qtype);
        if((mc = query_dname_compare(msg1->qname, msg2->qname)) != 0)
                return mc;
        log_assert(msg1->qname_len == msg2->qname_len);
        COMPARE_IT(msg1->qclass, msg2->qclass);
        return 0;
#undef COMPARE_IT
}

void 
query_info_clear(struct query_info* m)
{
        free(m->qname);
        m->qname = NULL;
}

size_t 
msgreply_sizefunc(void* k, void* d)
{
        struct msgreply_entry* q = (struct msgreply_entry*)k;
        struct reply_info* r = (struct reply_info*)d;
        size_t s = sizeof(struct msgreply_entry) + sizeof(struct reply_info)
                + q->key.qname_len + lock_get_mem(&q->entry.lock)
                - sizeof(struct rrset_ref);
        s += r->rrset_count * sizeof(struct rrset_ref);
        s += r->rrset_count * sizeof(struct ub_packed_rrset_key*);
        return s;
}

void 
query_entry_delete(void *k, void* ATTR_UNUSED(arg))
{
        struct msgreply_entry* q = (struct msgreply_entry*)k;
        lock_rw_destroy(&q->entry.lock);
        query_info_clear(&q->key);
        free(q);
}

void 
reply_info_delete(void* d, void* ATTR_UNUSED(arg))
{
        struct reply_info* r = (struct reply_info*)d;
        if(r->reason_bogus_str) {
                free(r->reason_bogus_str);
                r->reason_bogus_str = NULL;
        }
        free(r);
}

hashvalue_type
query_info_hash(struct query_info *q, uint16_t flags)
{
        hashvalue_type h = 0xab;
        h = hashlittle(&q->qtype, sizeof(q->qtype), h);
        if(q->qtype == LDNS_RR_TYPE_AAAA && (flags&BIT_CD))
                h++;
        h = hashlittle(&q->qclass, sizeof(q->qclass), h);
        h = dname_query_hash(q->qname, h);
        return h;
}

struct msgreply_entry* 
query_info_entrysetup(struct query_info* q, struct reply_info* r, 
        hashvalue_type h)
{
        struct msgreply_entry* e = (struct msgreply_entry*)malloc( 
                sizeof(struct msgreply_entry));
        if(!e) return NULL;
        memcpy(&e->key, q, sizeof(*q));
        e->entry.hash = h;
        e->entry.key = e;
        e->entry.data = r;
        lock_rw_init(&e->entry.lock);
        lock_protect(&e->entry.lock, &e->key.qname, sizeof(e->key.qname));
        lock_protect(&e->entry.lock, &e->key.qname_len, sizeof(e->key.qname_len));
        lock_protect(&e->entry.lock, &e->key.qtype, sizeof(e->key.qtype));
        lock_protect(&e->entry.lock, &e->key.qclass, sizeof(e->key.qclass));
        lock_protect(&e->entry.lock, &e->key.local_alias, sizeof(e->key.local_alias));
        lock_protect(&e->entry.lock, &e->entry.hash, sizeof(e->entry.hash));
        lock_protect(&e->entry.lock, &e->entry.key, sizeof(e->entry.key));
        lock_protect(&e->entry.lock, &e->entry.data, sizeof(e->entry.data));
        lock_protect(&e->entry.lock, e->key.qname, e->key.qname_len);
        q->qname = NULL;
        return e;
}

/** copy rrsets from replyinfo to dest replyinfo */
static int
repinfo_copy_rrsets(struct reply_info* dest, struct reply_info* from, 
        struct regional* region)
{
        size_t i, s;
        struct packed_rrset_data* fd, *dd;
        struct ub_packed_rrset_key* fk, *dk;
        for(i=0; i<dest->rrset_count; i++) {
                fk = from->rrsets[i];
                dk = dest->rrsets[i];
                fd = (struct packed_rrset_data*)fk->entry.data;
                dk->entry.hash = fk->entry.hash;
                dk->rk = fk->rk;
                if(region) {
                        dk->id = fk->id;
                        dk->rk.dname = (uint8_t*)regional_alloc_init(region,
                                fk->rk.dname, fk->rk.dname_len);
                } else  
                        dk->rk.dname = (uint8_t*)memdup(fk->rk.dname, 
                                fk->rk.dname_len);
                if(!dk->rk.dname)
                        return 0;
                s = packed_rrset_sizeof(fd);
                if(region)
                        dd = (struct packed_rrset_data*)regional_alloc_init(
                                region, fd, s);
                else    dd = (struct packed_rrset_data*)memdup(fd, s);
                if(!dd) 
                        return 0;
                packed_rrset_ptr_fixup(dd);
                dk->entry.data = (void*)dd;
        }
        return 1;
}

struct reply_info*
reply_info_copy(struct reply_info* rep, struct alloc_cache* alloc,
        struct regional* region)
{
        struct reply_info* cp;
        cp = construct_reply_info_base(region, rep->flags, rep->qdcount,
                rep->ttl, rep->prefetch_ttl, rep->serve_expired_ttl,
                rep->serve_expired_norec_ttl,
                rep->an_numrrsets, rep->ns_numrrsets, rep->ar_numrrsets,
                rep->rrset_count, rep->security, rep->reason_bogus);
        if(!cp)
                return NULL;

        if(rep->reason_bogus_str && *rep->reason_bogus_str != 0) {
                if(region) {
                        cp->reason_bogus_str = (char*)regional_alloc(region,
                                sizeof(char)
                                * (strlen(rep->reason_bogus_str)+1));
                } else {
                        cp->reason_bogus_str = malloc(sizeof(char)
                                * (strlen(rep->reason_bogus_str)+1));
                }
                if(!cp->reason_bogus_str) {
                        if(!region)
                                reply_info_parsedelete(cp, alloc);
                        return NULL;
                }
                memcpy(cp->reason_bogus_str, rep->reason_bogus_str,
                        strlen(rep->reason_bogus_str)+1);
        }

        /* allocate ub_key structures special or not */
        if(!reply_info_alloc_rrset_keys(cp, alloc, region)) {
                if(!region)
                        reply_info_parsedelete(cp, alloc);
                return NULL;
        }
        if(!repinfo_copy_rrsets(cp, rep, region)) {
                if(!region)
                        reply_info_parsedelete(cp, alloc);
                return NULL;
        }
        return cp;
}

uint8_t* 
reply_find_final_cname_target(struct query_info* qinfo, struct reply_info* rep)
{
        uint8_t* sname = qinfo->qname;
        size_t snamelen = qinfo->qname_len;
        size_t i;
        for(i=0; i<rep->an_numrrsets; i++) {
                struct ub_packed_rrset_key* s = rep->rrsets[i];
                /* follow CNAME chain (if any) */
                if(ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME && 
                        ntohs(s->rk.rrset_class) == qinfo->qclass && 
                        snamelen == s->rk.dname_len &&
                        query_dname_compare(sname, s->rk.dname) == 0) {
                        get_cname_target(s, &sname, &snamelen);
                }
        }
        if(sname != qinfo->qname)
                return sname;
        return NULL;
}

struct ub_packed_rrset_key* 
reply_find_answer_rrset(struct query_info* qinfo, struct reply_info* rep)
{
        uint8_t* sname = qinfo->qname;
        size_t snamelen = qinfo->qname_len;
        size_t i;
        for(i=0; i<rep->an_numrrsets; i++) {
                struct ub_packed_rrset_key* s = rep->rrsets[i];
                /* first match type, for query of qtype cname */
                if(ntohs(s->rk.type) == qinfo->qtype && 
                        ntohs(s->rk.rrset_class) == qinfo->qclass && 
                        snamelen == s->rk.dname_len &&
                        query_dname_compare(sname, s->rk.dname) == 0) {
                        return s;
                }
                /* follow CNAME chain (if any) */
                if(ntohs(s->rk.type) == LDNS_RR_TYPE_CNAME && 
                        ntohs(s->rk.rrset_class) == qinfo->qclass && 
                        snamelen == s->rk.dname_len &&
                        query_dname_compare(sname, s->rk.dname) == 0) {
                        get_cname_target(s, &sname, &snamelen);
                }
        }
        return NULL;
}

struct ub_packed_rrset_key* reply_find_rrset_section_an(struct reply_info* rep,
        uint8_t* name, size_t namelen, uint16_t type, uint16_t dclass)
{
        size_t i;
        for(i=0; i<rep->an_numrrsets; i++) {
                struct ub_packed_rrset_key* s = rep->rrsets[i];
                if(ntohs(s->rk.type) == type && 
                        ntohs(s->rk.rrset_class) == dclass && 
                        namelen == s->rk.dname_len &&
                        query_dname_compare(name, s->rk.dname) == 0) {
                        return s;
                }
        }
        return NULL;
}

struct ub_packed_rrset_key* reply_find_rrset_section_ns(struct reply_info* rep,
        uint8_t* name, size_t namelen, uint16_t type, uint16_t dclass)
{
        size_t i;
        for(i=rep->an_numrrsets; i<rep->an_numrrsets+rep->ns_numrrsets; i++) {
                struct ub_packed_rrset_key* s = rep->rrsets[i];
                if(ntohs(s->rk.type) == type && 
                        ntohs(s->rk.rrset_class) == dclass && 
                        namelen == s->rk.dname_len &&
                        query_dname_compare(name, s->rk.dname) == 0) {
                        return s;
                }
        }
        return NULL;
}

struct ub_packed_rrset_key* reply_find_rrset(struct reply_info* rep,
        uint8_t* name, size_t namelen, uint16_t type, uint16_t dclass)
{
        size_t i;
        for(i=0; i<rep->rrset_count; i++) {
                struct ub_packed_rrset_key* s = rep->rrsets[i];
                if(ntohs(s->rk.type) == type && 
                        ntohs(s->rk.rrset_class) == dclass && 
                        namelen == s->rk.dname_len &&
                        query_dname_compare(name, s->rk.dname) == 0) {
                        return s;
                }
        }
        return NULL;
}

void 
log_dns_msg(const char* str, struct query_info* qinfo, struct reply_info* rep)
{
        /* not particularly fast but flexible, make wireformat and print */
        sldns_buffer* buf = sldns_buffer_new(65535);
        struct regional* region = regional_create();
        if(!(buf && region)) {
                log_err("%s: log_dns_msg: out of memory", str);
                sldns_buffer_free(buf);
                regional_destroy(region);
                return;
        }
        if(!reply_info_encode(qinfo, rep, 0, rep->flags, buf, 0,
                region, 65535, 1, 0)) {
                log_err("%s: log_dns_msg: out of memory", str);
        } else {
                char* s = sldns_wire2str_pkt(sldns_buffer_begin(buf),
                        sldns_buffer_limit(buf));
                if(!s) {
                        log_info("%s: log_dns_msg: ldns tostr failed", str);
                } else {
                        log_info("%s %s", str, s);
                }
                free(s);
        }
        sldns_buffer_free(buf);
        regional_destroy(region);
}

void
log_reply_info(enum verbosity_value v, struct query_info *qinf,
        struct sockaddr_storage *addr, socklen_t addrlen, struct timeval dur,
        int cached, struct sldns_buffer *rmsg, struct sockaddr_storage* daddr,
        enum comm_point_type tp, void* ssl)
{
        char clientip_buf[128];
        char rcode_buf[16];
        char dest_buf[160];
        uint16_t rcode = FLAGS_GET_RCODE(sldns_buffer_read_u16_at(rmsg, 2));

        if(verbosity < v)
          return;

        sldns_wire2str_rcode_buf((int)rcode, rcode_buf, sizeof(rcode_buf));
        addr_to_str(addr, addrlen, clientip_buf, sizeof(clientip_buf));
        if(daddr) {
                char da[128];
                int port = 0;
                char* comm;
                if(daddr->ss_family == AF_INET6) {
                        struct sockaddr_in6 *d = (struct sockaddr_in6 *)daddr;
                        if(inet_ntop(d->sin6_family, &d->sin6_addr, da,
                                sizeof(da)) == 0)
                                snprintf(dest_buf, sizeof(dest_buf),
                                        "(inet_ntop_error)");
                        port = ntohs(d->sin6_port);
                } else if(daddr->ss_family == AF_INET) {
                        struct sockaddr_in *d = (struct sockaddr_in *)daddr;
                        if(inet_ntop(d->sin_family, &d->sin_addr, da,
                                sizeof(da)) == 0)
                                snprintf(dest_buf, sizeof(dest_buf),
                                        "(inet_ntop_error)");
                        port = ntohs(d->sin_port);
                } else {
                        snprintf(da, sizeof(da), "socket%d",
                                (int)daddr->ss_family);
                }
                comm = "udp";
                if(tp == comm_tcp) comm = (ssl?"dot":"tcp");
                else if(tp == comm_tcp_accept) comm = (ssl?"dot":"tcp");
                else if(tp == comm_http) comm = "doh";
                else if(tp == comm_local) comm = "unix";
                else if(tp == comm_raw) comm = "raw";
                snprintf(dest_buf, sizeof(dest_buf), " on %s %s %d",
                        comm, da, port);
        } else {
                dest_buf[0]=0;
        }
        if(rcode == LDNS_RCODE_FORMERR)
        {
                if(LOG_TAG_QUERYREPLY)
                        log_reply("%s - - - %s - - -%s", clientip_buf,
                                rcode_buf, dest_buf);
                else    log_info("%s - - - %s - - -%s", clientip_buf,
                                rcode_buf, dest_buf);
        } else {
                char qname_buf[LDNS_MAX_DOMAINLEN];
                char type_buf[16];
                char class_buf[16];
                size_t pktlen;
                if(qinf->qname)
                        dname_str(qinf->qname, qname_buf);
                else    snprintf(qname_buf, sizeof(qname_buf), "null");
                pktlen = sldns_buffer_limit(rmsg);
                sldns_wire2str_type_buf(qinf->qtype, type_buf, sizeof(type_buf));
                sldns_wire2str_class_buf(qinf->qclass, class_buf, sizeof(class_buf));
                if(LOG_TAG_QUERYREPLY)
                     log_reply("%s %s %s %s %s " ARG_LL "d.%6.6d %d %d%s",
                        clientip_buf, qname_buf, type_buf, class_buf,
                        rcode_buf, (long long)dur.tv_sec, (int)dur.tv_usec,
                        cached, (int)pktlen, dest_buf);
                else log_info("%s %s %s %s %s " ARG_LL "d.%6.6d %d %d%s",
                        clientip_buf, qname_buf, type_buf, class_buf,
                        rcode_buf, (long long)dur.tv_sec, (int)dur.tv_usec,
                        cached, (int)pktlen, dest_buf);
        }
}

void
log_query_info(enum verbosity_value v, const char* str, 
        struct query_info* qinf)
{
        log_nametypeclass(v, str, qinf->qname, qinf->qtype, qinf->qclass);
}

int
reply_check_cname_chain(struct query_info* qinfo, struct reply_info* rep) 
{
        /* check only answer section rrs for matching cname chain.
         * the cache may return changed rdata, but owner names are untouched.*/
        size_t i;
        uint8_t* sname = qinfo->qname;
        size_t snamelen = qinfo->qname_len;
        for(i=0; i<rep->an_numrrsets; i++) {
                uint16_t t = ntohs(rep->rrsets[i]->rk.type);
                if(t == LDNS_RR_TYPE_DNAME)
                        continue; /* skip dnames; note TTL 0 not cached */
                /* verify that owner matches current sname */
                if(query_dname_compare(sname, rep->rrsets[i]->rk.dname) != 0){
                        /* cname chain broken */
                        return 0;
                }
                /* if this is a cname; move on */
                if(t == LDNS_RR_TYPE_CNAME) {
                        get_cname_target(rep->rrsets[i], &sname, &snamelen);
                }
        }
        return 1;
}

int
reply_all_rrsets_secure(struct reply_info* rep) 
{
        size_t i;
        for(i=0; i<rep->rrset_count; i++) {
                if( ((struct packed_rrset_data*)rep->rrsets[i]->entry.data)
                        ->security != sec_status_secure )
                return 0;
        }
        return 1;
}

struct reply_info*
parse_reply_in_temp_region(sldns_buffer* pkt, struct regional* region,
        struct query_info* qi)
{
        struct reply_info* rep;
        struct msg_parse* msg;
        if(!(msg = regional_alloc(region, sizeof(*msg)))) {
                return NULL;
        }
        memset(msg, 0, sizeof(*msg));
        sldns_buffer_set_position(pkt, 0);
        if(parse_packet(pkt, msg, region) != 0){
                return 0;
        }
        if(!parse_create_msg(pkt, msg, NULL, qi, &rep, region)) {
                return 0;
        }
        return rep;
}

int edns_opt_list_append_ede(struct edns_option** list, struct regional* region,
        sldns_ede_code code, const char *txt)
{
        struct edns_option** prevp;
        struct edns_option* opt;
        size_t txt_len = txt ? strlen(txt) : 0;

        /* allocate new element */
        opt = (struct edns_option*)regional_alloc(region, sizeof(*opt));
        if(!opt)
                return 0;
        opt->next = NULL;
        opt->opt_code = LDNS_EDNS_EDE;
        opt->opt_len = txt_len + sizeof(uint16_t);
        opt->opt_data = regional_alloc(region, txt_len + sizeof(uint16_t));
        if(!opt->opt_data)
                return 0;
        sldns_write_uint16(opt->opt_data, (uint16_t)code);
        if (txt_len)
                memmove(opt->opt_data + 2, txt, txt_len);

        /* append at end of list */
        prevp = list;
        while(*prevp != NULL)
                prevp = &((*prevp)->next);
        verbose(VERB_ALGO, "attached EDE code: %d with message: '%s'", code, (txt?txt:""));
        *prevp = opt;
        return 1;
}

int edns_opt_list_append_keepalive(struct edns_option** list, int msec,
        struct regional* region)
{
        uint8_t data[2]; /* For keepalive value */
        data[0] = (uint8_t)((msec >> 8) & 0xff);
        data[1] = (uint8_t)(msec & 0xff);
        return edns_opt_list_append(list, LDNS_EDNS_KEEPALIVE, sizeof(data),
                data, region);
}

int edns_opt_list_append(struct edns_option** list, uint16_t code, size_t len,
        uint8_t* data, struct regional* region)
{
        struct edns_option** prevp;
        struct edns_option* opt;

        /* allocate new element */
        opt = (struct edns_option*)regional_alloc(region, sizeof(*opt));
        if(!opt)
                return 0;
        opt->next = NULL;
        opt->opt_code = code;
        opt->opt_len = len;
        opt->opt_data = NULL;
        if(len > 0) {
                opt->opt_data = regional_alloc_init(region, data, len);
                if(!opt->opt_data)
                        return 0;
        }

        /* append at end of list */
        prevp = list;
        while(*prevp != NULL) {
                prevp = &((*prevp)->next);
        }
        *prevp = opt;
        return 1;
}

int edns_opt_list_remove(struct edns_option** list, uint16_t code)
{
        /* The list should already be allocated in a region. Freeing the
         * allocated space in a region is not possible. We just unlink the
         * required elements and they will be freed together with the region. */

        struct edns_option* prev;
        struct edns_option* curr;
        if(!list || !(*list)) return 0;

        /* Unlink and repoint if the element(s) are first in list */
        while(list && *list && (*list)->opt_code == code) {
                *list = (*list)->next;
        }

        if(!list || !(*list)) return 1;
        /* Unlink elements and reattach the list */
        prev = *list;
        curr = (*list)->next;
        while(curr != NULL) {
                if(curr->opt_code == code) {
                        prev->next = curr->next;
                        curr = curr->next;
                } else {
                        prev = curr;
                        curr = curr->next;
                }
        }
        return 1;
}

static int inplace_cb_reply_call_generic(
    struct inplace_cb* callback_list, enum inplace_cb_list_type type,
        struct query_info* qinfo, struct module_qstate* qstate,
        struct reply_info* rep, int rcode, struct edns_data* edns,
        struct comm_reply* repinfo, struct regional* region,
        struct timeval* start_time)
{
        struct inplace_cb* cb;
        struct edns_option* opt_list_out = NULL;
#if defined(EXPORT_ALL_SYMBOLS)
        (void)type; /* param not used when fptr_ok disabled */
#endif
        if(qstate)
                opt_list_out = qstate->edns_opts_front_out;
        for(cb=callback_list; cb; cb=cb->next) {
                fptr_ok(fptr_whitelist_inplace_cb_reply_generic(
                        (inplace_cb_reply_func_type*)cb->cb, type));
                (void)(*(inplace_cb_reply_func_type*)cb->cb)(qinfo, qstate, rep,
                        rcode, edns, &opt_list_out, repinfo, region, start_time, cb->id, cb->cb_arg);
        }
        edns->opt_list_inplace_cb_out = opt_list_out;
        return 1;
}

int inplace_cb_reply_call(struct module_env* env, struct query_info* qinfo,
        struct module_qstate* qstate, struct reply_info* rep, int rcode,
        struct edns_data* edns, struct comm_reply* repinfo, struct regional* region,
        struct timeval* start_time)
{
        return inplace_cb_reply_call_generic(
                env->inplace_cb_lists[inplace_cb_reply], inplace_cb_reply, qinfo,
                qstate, rep, rcode, edns, repinfo, region, start_time);
}

int inplace_cb_reply_cache_call(struct module_env* env,
        struct query_info* qinfo, struct module_qstate* qstate,
        struct reply_info* rep, int rcode, struct edns_data* edns,
        struct comm_reply* repinfo, struct regional* region,
        struct timeval* start_time)
{
        return inplace_cb_reply_call_generic(
                env->inplace_cb_lists[inplace_cb_reply_cache], inplace_cb_reply_cache,
                qinfo, qstate, rep, rcode, edns, repinfo, region, start_time);
}

int inplace_cb_reply_local_call(struct module_env* env,
        struct query_info* qinfo, struct module_qstate* qstate,
        struct reply_info* rep, int rcode, struct edns_data* edns,
        struct comm_reply* repinfo, struct regional* region,
        struct timeval* start_time)
{
        return inplace_cb_reply_call_generic(
                env->inplace_cb_lists[inplace_cb_reply_local], inplace_cb_reply_local,
                qinfo, qstate, rep, rcode, edns, repinfo, region, start_time);
}

int inplace_cb_reply_servfail_call(struct module_env* env,
        struct query_info* qinfo, struct module_qstate* qstate,
        struct reply_info* rep, int rcode, struct edns_data* edns,
        struct comm_reply* repinfo, struct regional* region,
        struct timeval* start_time)
{
        /* We are going to servfail. Remove any potential edns options. */
        if(qstate)
                qstate->edns_opts_front_out = NULL;
        return inplace_cb_reply_call_generic(
                env->inplace_cb_lists[inplace_cb_reply_servfail],
                inplace_cb_reply_servfail, qinfo, qstate, rep, rcode, edns, repinfo,
                region, start_time);
}

int inplace_cb_query_call(struct module_env* env, struct query_info* qinfo,
        uint16_t flags, struct sockaddr_storage* addr, socklen_t addrlen,
        uint8_t* zone, size_t zonelen, struct module_qstate* qstate,
        struct regional* region)
{
        struct inplace_cb* cb = env->inplace_cb_lists[inplace_cb_query];
        for(; cb; cb=cb->next) {
                fptr_ok(fptr_whitelist_inplace_cb_query(
                        (inplace_cb_query_func_type*)cb->cb));
                (void)(*(inplace_cb_query_func_type*)cb->cb)(qinfo, flags,
                        qstate, addr, addrlen, zone, zonelen, region,
                        cb->id, cb->cb_arg);
        }
        return 1;
}

int inplace_cb_edns_back_parsed_call(struct module_env* env, 
        struct module_qstate* qstate)
{
        struct inplace_cb* cb =
                env->inplace_cb_lists[inplace_cb_edns_back_parsed];
        for(; cb; cb=cb->next) {
                fptr_ok(fptr_whitelist_inplace_cb_edns_back_parsed(
                        (inplace_cb_edns_back_parsed_func_type*)cb->cb));
                (void)(*(inplace_cb_edns_back_parsed_func_type*)cb->cb)(qstate,
                        cb->id, cb->cb_arg);
        }
        return 1;
}

int inplace_cb_query_response_call(struct module_env* env,
        struct module_qstate* qstate, struct dns_msg* response) {
        struct inplace_cb* cb =
                env->inplace_cb_lists[inplace_cb_query_response];
        for(; cb; cb=cb->next) {
                fptr_ok(fptr_whitelist_inplace_cb_query_response(
                        (inplace_cb_query_response_func_type*)cb->cb));
                (void)(*(inplace_cb_query_response_func_type*)cb->cb)(qstate,
                        response, cb->id, cb->cb_arg);
        }
        return 1;
}

struct edns_option* edns_opt_copy_region(struct edns_option* list,
        struct regional* region)
{
        struct edns_option* result = NULL, *cur = NULL, *s;
        while(list) {
                /* copy edns option structure */
                s = regional_alloc_init(region, list, sizeof(*list));
                if(!s) return NULL;
                s->next = NULL;

                /* copy option data */
                if(s->opt_data) {
                        s->opt_data = regional_alloc_init(region, s->opt_data,
                                s->opt_len);
                        if(!s->opt_data)
                                return NULL;
                }

                /* link into list */
                if(cur)
                        cur->next = s;
                else    result = s;
                cur = s;

                /* examine next element */
                list = list->next;
        }
        return result;
}

struct edns_option* edns_opt_copy_filter_region(struct edns_option* list,
        uint16_t* filter_list, size_t filter_list_len, struct regional* region)
{
        struct edns_option* result = NULL, *cur = NULL, *s;
        size_t i;
        while(list) {
                for(i=0; i<filter_list_len; i++)
                        if(filter_list[i] == list->opt_code) goto found;
                if(i == filter_list_len) goto next;
found:
                /* copy edns option structure */
                s = regional_alloc_init(region, list, sizeof(*list));
                if(!s) return NULL;
                s->next = NULL;

                /* copy option data */
                if(s->opt_data) {
                        s->opt_data = regional_alloc_init(region, s->opt_data,
                                s->opt_len);
                        if(!s->opt_data)
                                return NULL;
                }

                /* link into list */
                if(cur)
                        cur->next = s;
                else    result = s;
                cur = s;

next:
                /* examine next element */
                list = list->next;
        }
        return result;
}

int edns_opt_compare(struct edns_option* p, struct edns_option* q)
{
        if(!p && !q) return 0;
        if(!p) return -1;
        if(!q) return 1;
        log_assert(p && q);
        if(p->opt_code != q->opt_code)
                return (int)q->opt_code - (int)p->opt_code;
        if(p->opt_len != q->opt_len)
                return (int)q->opt_len - (int)p->opt_len;
        if(p->opt_len != 0)
                return memcmp(p->opt_data, q->opt_data, p->opt_len);
        return 0;
}

int edns_opt_list_compare(struct edns_option* p, struct edns_option* q)
{
        int r;
        while(p && q) {
                r = edns_opt_compare(p, q);
                if(r != 0)
                        return r;
                p = p->next;
                q = q->next;
        }
        if(p || q) {
                /* uneven length lists */
                if(p) return 1;
                if(q) return -1;
        }
        return 0;
}

void edns_opt_list_free(struct edns_option* list)
{
        struct edns_option* n;
        while(list) {
                free(list->opt_data);
                n = list->next;
                free(list);
                list = n;
        }
}

struct edns_option* edns_opt_copy_alloc(struct edns_option* list)
{
        struct edns_option* result = NULL, *cur = NULL, *s;
        while(list) {
                /* copy edns option structure */
                s = memdup(list, sizeof(*list));
                if(!s) {
                        edns_opt_list_free(result);
                        return NULL;
                }
                s->next = NULL;

                /* copy option data */
                if(s->opt_data) {
                        s->opt_data = memdup(s->opt_data, s->opt_len);
                        if(!s->opt_data) {
                                free(s);
                                edns_opt_list_free(result);
                                return NULL;
                        }
                }

                /* link into list */
                if(cur)
                        cur->next = s;
                else    result = s;
                cur = s;

                /* examine next element */
                list = list->next;
        }
        return result;
}

struct edns_option* edns_opt_list_find(struct edns_option* list, uint16_t code)
{
        struct edns_option* p;
        for(p=list; p; p=p->next) {
                if(p->opt_code == code)
                        return p;
        }
        return NULL;
}

int local_alias_shallow_copy_qname(struct local_rrset* local_alias, uint8_t** qname,
        size_t* qname_len)
{
        struct ub_packed_rrset_key* rrset = local_alias->rrset;
        struct packed_rrset_data* d = rrset->entry.data;

        /* Sanity check: our current implementation only supports
            * a single CNAME RRset as a local alias. */
        if(local_alias->next ||
                rrset->rk.type != htons(LDNS_RR_TYPE_CNAME) ||
                d->count != 1) {
                log_err("assumption failure: unexpected local alias");
                return 0;
        }
        *qname = d->rr_data[0] + 2;
        *qname_len = d->rr_len[0] - 2;
        return 1;
}