text: /*
   * 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 */
  /** If we serve expired entries and prefetch them */
  int SERVE_EXPIRED = 0;
  /** Time to serve records after expiration */
  time_t SERVE_EXPIRED_TTL = 0;
  /** TTL to use for expired records */
  time_t SERVE_EXPIRED_REPLY_TTL = 30;
  
  /** 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, size_t an, size_t ns,
  	size_t ar, size_t total, enum sec_status sec)
  {
  	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->an_numrrsets = an;
  	rep->ns_numrrsets = ns;
  	rep->ar_numrrsets = ar;
  	rep->rrset_count = total;
  	rep->security = sec;
  	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, msg->an_rrsets, msg->ns_rrsets, msg->ar_rrsets, 
  		msg->rrset_count, sec_status_unchecked);
  	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;
  }
  
  /** 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(*rr_ttl > MAX_NEG_TTL)
  			*rr_ttl = MAX_NEG_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(region, s);
  	else	*data = malloc(s);
  	if(!*data)
  		return 0;
  	/* copy & decompress */
  	if(!parse_rr_copy(pkt, pset, *data)) {
  		if(!region) free(*data);
  		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))
  		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;
  	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(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);
  		reply_info_parsedelete(*rep, alloc);
  		*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;
  	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;
  		}
  	}
  }
  
  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);
  	}
  	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;
  	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->an_numrrsets, rep->ns_numrrsets, rep->ar_numrrsets,
  		rep->rrset_count, rep->security);
  	if(!cp)
  		return NULL;
  	/* 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(!reply_info_encode(qinfo, rep, 0, rep->flags, buf, 0, 
  		region, 65535, 1, 0)) {
  		log_info("%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)
  {
  	char qname_buf[LDNS_MAX_DOMAINLEN+1];
  	char clientip_buf[128];
  	char rcode_buf[16];
  	char type_buf[16];
  	char class_buf[16];
  	size_t pktlen;
  	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(rcode == LDNS_RCODE_FORMERR)
  	{
  		if(LOG_TAG_QUERYREPLY)
  			log_reply("%s - - - %s - - - ", clientip_buf, rcode_buf);
  		else	log_info("%s - - - %s - - - ", clientip_buf, rcode_buf);
  	} else {
  		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",
  			clientip_buf, qname_buf, type_buf, class_buf,
  			rcode_buf, (long long)dur.tv_sec, (int)dur.tv_usec, cached, (int)pktlen);
  		else log_info("%s %s %s %s %s " ARG_LL "d.%6.6d %d %d",
  			clientip_buf, qname_buf, type_buf, class_buf,
  			rcode_buf, (long long)dur.tv_sec, (int)dur.tv_usec, cached, (int)pktlen);
  	}
  }
  
  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_append(struct edns_data* edns, struct regional* region,
  	uint16_t code, size_t len, uint8_t* data)
  {
  	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 = &edns->opt_list;
  	while(*prevp != NULL)
  		prevp = &((*prevp)->next);
  	*prevp = opt;
  	return 1;
  }
  
  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 = 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;
  }
  
  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;
  }
  