added unbound to external deps

1 files changed, 841 insertions, 0 deletions

diff --git a/external/unbound/util/data/msgencode.c b/external/unbound/util/data/msgencode.c
new file mode 100644
index 000000000..26b5deabe
--- /dev/null
+++ b/external/unbound/util/data/msgencode.c
@@ -0,0 +1,841 @@
+/*
+ * util/data/msgencode.c - Encode DNS messages, queries and replies.
+ *
+ * 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 routines to encode DNS messages.
+ */
+
+#include "config.h"
+#include "util/data/msgencode.h"
+#include "util/data/msgreply.h"
+#include "util/data/msgparse.h"
+#include "util/data/dname.h"
+#include "util/log.h"
+#include "util/regional.h"
+#include "util/net_help.h"
+#include "ldns/sbuffer.h"
+
+/** return code that means the function ran out of memory. negative so it does
+ * not conflict with DNS rcodes. */
+#define RETVAL_OUTMEM	-2
+/** return code that means the data did not fit (completely) in the packet */
+#define RETVAL_TRUNC	-4
+/** return code that means all is peachy keen. Equal to DNS rcode NOERROR */
+#define RETVAL_OK	0
+
+/**
+ * Data structure to help domain name compression in outgoing messages.
+ * A tree of dnames and their offsets in the packet is kept.
+ * It is kept sorted, not canonical, but by label at least, so that after
+ * a lookup of a name you know its closest match, and the parent from that
+ * closest match. These are possible compression targets.
+ *
+ * It is a binary tree, not a rbtree or balanced tree, as the effort
+ * of keeping it balanced probably outweighs usefulness (given typical
+ * DNS packet size).
+ */
+struct compress_tree_node {
+	/** left node in tree, all smaller to this */
+	struct compress_tree_node* left;
+	/** right node in tree, all larger than this */
+	struct compress_tree_node* right;
+
+	/** the parent node - not for tree, but zone parent. One less label */
+	struct compress_tree_node* parent;
+	/** the domain name for this node. Pointer to uncompressed memory. */
+	uint8_t* dname;
+	/** number of labels in domain name, kept to help compare func. */
+	int labs;
+	/** offset in packet that points to this dname */
+	size_t offset;
+};
+
+/**
+ * Find domain name in tree, returns exact and closest match.
+ * @param tree: root of tree.
+ * @param dname: pointer to uncompressed dname.
+ * @param labs: number of labels in domain name.
+ * @param match: closest or exact match.
+ *	guaranteed to be smaller or equal to the sought dname.
+ *	can be null if the tree is empty.
+ * @param matchlabels: number of labels that match with closest match.
+ *	can be zero is there is no match.
+ * @param insertpt: insert location for dname, if not found.
+ * @return: 0 if no exact match.
+ */
+static int
+compress_tree_search(struct compress_tree_node** tree, uint8_t* dname,
+	int labs, struct compress_tree_node** match, int* matchlabels,
+	struct compress_tree_node*** insertpt)
+{
+	int c, n, closen=0;
+	struct compress_tree_node* p = *tree;
+	struct compress_tree_node* close = 0;
+	struct compress_tree_node** prev = tree;
+	while(p) {
+		if((c = dname_lab_cmp(dname, labs, p->dname, p->labs, &n)) 
+			== 0) {
+			*matchlabels = n;
+			*match = p;
+			return 1;
+		}
+		if(c<0) {
+			prev = &p->left;
+			p = p->left;
+		} else	{
+			closen = n;
+			close = p; /* p->dname is smaller than dname */
+			prev = &p->right;
+			p = p->right;
+		}
+	}
+	*insertpt = prev;
+	*matchlabels = closen;
+	*match = close;
+	return 0;
+}
+
+/**
+ * Lookup a domain name in compression tree.
+ * @param tree: root of tree (not the node with '.').
+ * @param dname: pointer to uncompressed dname.
+ * @param labs: number of labels in domain name.
+ * @param insertpt: insert location for dname, if not found.
+ * @return: 0 if not found or compress treenode with best compression.
+ */
+static struct compress_tree_node*
+compress_tree_lookup(struct compress_tree_node** tree, uint8_t* dname,
+	int labs, struct compress_tree_node*** insertpt)
+{
+	struct compress_tree_node* p;
+	int m;
+	if(labs <= 1)
+		return 0; /* do not compress root node */
+	if(compress_tree_search(tree, dname, labs, &p, &m, insertpt)) {
+		/* exact match */
+		return p;
+	}
+	/* return some ancestor of p that compresses well. */
+	if(m>1) {
+		/* www.example.com. (labs=4) matched foo.example.com.(labs=4)
+		 * then matchcount = 3. need to go up. */
+		while(p && p->labs > m)
+			p = p->parent;
+		return p;
+	}
+	return 0;
+}
+
+/**
+ * Create node for domain name compression tree.
+ * @param dname: pointer to uncompressed dname (stored in tree).
+ * @param labs: number of labels in dname.
+ * @param offset: offset into packet for dname.
+ * @param region: how to allocate memory for new node.
+ * @return new node or 0 on malloc failure.
+ */
+static struct compress_tree_node*
+compress_tree_newnode(uint8_t* dname, int labs, size_t offset, 
+	struct regional* region)
+{
+	struct compress_tree_node* n = (struct compress_tree_node*)
+		regional_alloc(region, sizeof(struct compress_tree_node));
+	if(!n) return 0;
+	n->left = 0;
+	n->right = 0;
+	n->parent = 0;
+	n->dname = dname;
+	n->labs = labs;
+	n->offset = offset;
+	return n;
+}
+
+/**
+ * Store domain name and ancestors into compression tree.
+ * @param dname: pointer to uncompressed dname (stored in tree).
+ * @param labs: number of labels in dname.
+ * @param offset: offset into packet for dname.
+ * @param region: how to allocate memory for new node.
+ * @param closest: match from previous lookup, used to compress dname.
+ *	may be NULL if no previous match.
+ *	if the tree has an ancestor of dname already, this must be it.
+ * @param insertpt: where to insert the dname in tree. 
+ * @return: 0 on memory error.
+ */
+static int
+compress_tree_store(uint8_t* dname, int labs, size_t offset, 
+	struct regional* region, struct compress_tree_node* closest, 
+	struct compress_tree_node** insertpt)
+{
+	uint8_t lablen;
+	struct compress_tree_node* newnode;
+	struct compress_tree_node* prevnode = NULL;
+	int uplabs = labs-1; /* does not store root in tree */
+	if(closest) uplabs = labs - closest->labs;
+	log_assert(uplabs >= 0);
+	/* algorithms builds up a vine of dname-labels to hang into tree */
+	while(uplabs--) {
+		if(offset > PTR_MAX_OFFSET) {
+			/* insertion failed, drop vine */
+			return 1; /* compression pointer no longer useful */
+		}
+		if(!(newnode = compress_tree_newnode(dname, labs, offset, 
+			region))) {
+			/* insertion failed, drop vine */
+			return 0;
+		}
+
+		if(prevnode) {
+			/* chain nodes together, last one has one label more,
+			 * so is larger than newnode, thus goes right. */
+			newnode->right = prevnode;
+			prevnode->parent = newnode;
+		}
+
+		/* next label */
+		lablen = *dname++;
+		dname += lablen;
+		offset += lablen+1;
+		prevnode = newnode;
+		labs--;
+	}
+	/* if we have a vine, hang the vine into the tree */
+	if(prevnode) {
+		*insertpt = prevnode;
+		prevnode->parent = closest;
+	}
+	return 1;
+}
+
+/** compress a domain name */
+static int
+write_compressed_dname(sldns_buffer* pkt, uint8_t* dname, int labs,
+	struct compress_tree_node* p)
+{
+	/* compress it */
+	int labcopy = labs - p->labs;
+	uint8_t lablen;
+	uint16_t ptr;
+
+	if(labs == 1) {
+		/* write root label */
+		if(sldns_buffer_remaining(pkt) < 1)
+			return 0;
+		sldns_buffer_write_u8(pkt, 0);
+		return 1;
+	}
+
+	/* copy the first couple of labels */
+	while(labcopy--) {
+		lablen = *dname++;
+		if(sldns_buffer_remaining(pkt) < (size_t)lablen+1)
+			return 0;
+		sldns_buffer_write_u8(pkt, lablen);
+		sldns_buffer_write(pkt, dname, lablen);
+		dname += lablen;
+	}
+	/* insert compression ptr */
+	if(sldns_buffer_remaining(pkt) < 2)
+		return 0;
+	ptr = PTR_CREATE(p->offset);
+	sldns_buffer_write_u16(pkt, ptr);
+	return 1;
+}
+
+/** compress owner name of RR, return RETVAL_OUTMEM RETVAL_TRUNC */
+static int
+compress_owner(struct ub_packed_rrset_key* key, sldns_buffer* pkt, 
+	struct regional* region, struct compress_tree_node** tree, 
+	size_t owner_pos, uint16_t* owner_ptr, int owner_labs)
+{
+	struct compress_tree_node* p;
+	struct compress_tree_node** insertpt;
+	if(!*owner_ptr) {
+		/* compress first time dname */
+		if((p = compress_tree_lookup(tree, key->rk.dname, 
+			owner_labs, &insertpt))) {
+			if(p->labs == owner_labs) 
+				/* avoid ptr chains, since some software is
+				 * not capable of decoding ptr after a ptr. */
+				*owner_ptr = htons(PTR_CREATE(p->offset));
+			if(!write_compressed_dname(pkt, key->rk.dname, 
+				owner_labs, p))
+				return RETVAL_TRUNC;
+			/* check if typeclass+4 ttl + rdatalen is available */
+			if(sldns_buffer_remaining(pkt) < 4+4+2)
+				return RETVAL_TRUNC;
+		} else {
+			/* no compress */
+			if(sldns_buffer_remaining(pkt) < key->rk.dname_len+4+4+2)
+				return RETVAL_TRUNC;
+			sldns_buffer_write(pkt, key->rk.dname, 
+				key->rk.dname_len);
+			if(owner_pos <= PTR_MAX_OFFSET)
+				*owner_ptr = htons(PTR_CREATE(owner_pos));
+		}
+		if(!compress_tree_store(key->rk.dname, owner_labs, 
+			owner_pos, region, p, insertpt))
+			return RETVAL_OUTMEM;
+	} else {
+		/* always compress 2nd-further RRs in RRset */
+		if(owner_labs == 1) {
+			if(sldns_buffer_remaining(pkt) < 1+4+4+2) 
+				return RETVAL_TRUNC;
+			sldns_buffer_write_u8(pkt, 0);
+		} else {
+			if(sldns_buffer_remaining(pkt) < 2+4+4+2) 
+				return RETVAL_TRUNC;
+			sldns_buffer_write(pkt, owner_ptr, 2);
+		}
+	}
+	return RETVAL_OK;
+}
+
+/** compress any domain name to the packet, return RETVAL_* */
+static int
+compress_any_dname(uint8_t* dname, sldns_buffer* pkt, int labs, 
+	struct regional* region, struct compress_tree_node** tree)
+{
+	struct compress_tree_node* p;
+	struct compress_tree_node** insertpt = NULL;
+	size_t pos = sldns_buffer_position(pkt);
+	if((p = compress_tree_lookup(tree, dname, labs, &insertpt))) {
+		if(!write_compressed_dname(pkt, dname, labs, p))
+			return RETVAL_TRUNC;
+	} else {
+		if(!dname_buffer_write(pkt, dname))
+			return RETVAL_TRUNC;
+	}
+	if(!compress_tree_store(dname, labs, pos, region, p, insertpt))
+		return RETVAL_OUTMEM;
+	return RETVAL_OK;
+}
+
+/** return true if type needs domain name compression in rdata */
+static const sldns_rr_descriptor*
+type_rdata_compressable(struct ub_packed_rrset_key* key)
+{
+	uint16_t t = ntohs(key->rk.type);
+	if(sldns_rr_descript(t) && 
+		sldns_rr_descript(t)->_compress == LDNS_RR_COMPRESS)
+		return sldns_rr_descript(t);
+	return 0;
+}
+
+/** compress domain names in rdata, return RETVAL_* */
+static int
+compress_rdata(sldns_buffer* pkt, uint8_t* rdata, size_t todolen, 
+	struct regional* region, struct compress_tree_node** tree, 
+	const sldns_rr_descriptor* desc)
+{
+	int labs, r, rdf = 0;
+	size_t dname_len, len, pos = sldns_buffer_position(pkt);
+	uint8_t count = desc->_dname_count;
+
+	sldns_buffer_skip(pkt, 2); /* rdata len fill in later */
+	/* space for rdatalen checked for already */
+	rdata += 2;
+	todolen -= 2;
+	while(todolen > 0 && count) {
+		switch(desc->_wireformat[rdf]) {
+		case LDNS_RDF_TYPE_DNAME:
+			labs = dname_count_size_labels(rdata, &dname_len);
+			if((r=compress_any_dname(rdata, pkt, labs, region, 
+				tree)) != RETVAL_OK)
+				return r;
+			rdata += dname_len;
+			todolen -= dname_len;
+			count--;
+			len = 0;
+			break;
+		case LDNS_RDF_TYPE_STR:
+			len = *rdata + 1;
+			break;
+		default:
+			len = get_rdf_size(desc->_wireformat[rdf]);
+		}
+		if(len) {
+			/* copy over */
+			if(sldns_buffer_remaining(pkt) < len)
+				return RETVAL_TRUNC;
+			sldns_buffer_write(pkt, rdata, len);
+			todolen -= len;
+			rdata += len;
+		}
+		rdf++;
+	}
+	/* copy remainder */
+	if(todolen > 0) {
+		if(sldns_buffer_remaining(pkt) < todolen)
+			return RETVAL_TRUNC;
+		sldns_buffer_write(pkt, rdata, todolen);
+	}
+
+	/* set rdata len */
+	sldns_buffer_write_u16_at(pkt, pos, sldns_buffer_position(pkt)-pos-2);
+	return RETVAL_OK;
+}
+
+/** Returns true if RR type should be included */
+static int
+rrset_belongs_in_reply(sldns_pkt_section s, uint16_t rrtype, uint16_t qtype, 
+	int dnssec)
+{
+	if(dnssec)
+		return 1;
+	/* skip non DNSSEC types, except if directly queried for */
+	if(s == LDNS_SECTION_ANSWER) {
+		if(qtype == LDNS_RR_TYPE_ANY || qtype == rrtype)
+			return 1;
+	}
+	/* check DNSSEC-ness */
+	switch(rrtype) {
+		case LDNS_RR_TYPE_SIG:
+		case LDNS_RR_TYPE_KEY:
+		case LDNS_RR_TYPE_NXT:
+		case LDNS_RR_TYPE_DS:
+		case LDNS_RR_TYPE_RRSIG:
+		case LDNS_RR_TYPE_NSEC:
+		case LDNS_RR_TYPE_DNSKEY:
+		case LDNS_RR_TYPE_NSEC3:
+		case LDNS_RR_TYPE_NSEC3PARAMS:
+			return 0;
+	}
+	return 1;
+}
+
+/** store rrset in buffer in wireformat, return RETVAL_* */
+static int
+packed_rrset_encode(struct ub_packed_rrset_key* key, sldns_buffer* pkt, 
+	uint16_t* num_rrs, time_t timenow, struct regional* region,
+	int do_data, int do_sig, struct compress_tree_node** tree,
+	sldns_pkt_section s, uint16_t qtype, int dnssec, size_t rr_offset)
+{
+	size_t i, j, owner_pos;
+	int r, owner_labs;
+	uint16_t owner_ptr = 0;
+	struct packed_rrset_data* data = (struct packed_rrset_data*)
+		key->entry.data;
+	
+	/* does this RR type belong in the answer? */
+	if(!rrset_belongs_in_reply(s, ntohs(key->rk.type), qtype, dnssec))
+		return RETVAL_OK;
+
+	owner_labs = dname_count_labels(key->rk.dname);
+	owner_pos = sldns_buffer_position(pkt);
+
+	if(do_data) {
+		const sldns_rr_descriptor* c = type_rdata_compressable(key);
+		for(i=0; i<data->count; i++) {
+			/* rrset roundrobin */
+			j = (i + rr_offset) % data->count;
+			if((r=compress_owner(key, pkt, region, tree, 
+				owner_pos, &owner_ptr, owner_labs))
+				!= RETVAL_OK)
+				return r;
+			sldns_buffer_write(pkt, &key->rk.type, 2);
+			sldns_buffer_write(pkt, &key->rk.rrset_class, 2);
+			if(data->rr_ttl[j] < timenow)
+				sldns_buffer_write_u32(pkt, 0);
+			else 	sldns_buffer_write_u32(pkt, 
+					data->rr_ttl[j]-timenow);
+			if(c) {
+				if((r=compress_rdata(pkt, data->rr_data[j],
+					data->rr_len[j], region, tree, c))
+					!= RETVAL_OK)
+					return r;
+			} else {
+				if(sldns_buffer_remaining(pkt) < data->rr_len[j])
+					return RETVAL_TRUNC;
+				sldns_buffer_write(pkt, data->rr_data[j],
+					data->rr_len[j]);
+			}
+		}
+	}
+	/* insert rrsigs */
+	if(do_sig && dnssec) {
+		size_t total = data->count+data->rrsig_count;
+		for(i=data->count; i<total; i++) {
+			if(owner_ptr && owner_labs != 1) {
+				if(sldns_buffer_remaining(pkt) <
+					2+4+4+data->rr_len[i]) 
+					return RETVAL_TRUNC;
+				sldns_buffer_write(pkt, &owner_ptr, 2);
+			} else {
+				if((r=compress_any_dname(key->rk.dname, 
+					pkt, owner_labs, region, tree))
+					!= RETVAL_OK)
+					return r;
+				if(sldns_buffer_remaining(pkt) < 
+					4+4+data->rr_len[i])
+					return RETVAL_TRUNC;
+			}
+			sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_RRSIG);
+			sldns_buffer_write(pkt, &key->rk.rrset_class, 2);
+			if(data->rr_ttl[i] < timenow)
+				sldns_buffer_write_u32(pkt, 0);
+			else 	sldns_buffer_write_u32(pkt, 
+					data->rr_ttl[i]-timenow);
+			/* rrsig rdata cannot be compressed, perform 100+ byte
+			 * memcopy. */
+			sldns_buffer_write(pkt, data->rr_data[i],
+				data->rr_len[i]);
+		}
+	}
+	/* change rrnum only after we are sure it fits */
+	if(do_data)
+		*num_rrs += data->count;
+	if(do_sig && dnssec)
+		*num_rrs += data->rrsig_count;
+
+	return RETVAL_OK;
+}
+
+/** store msg section in wireformat buffer, return RETVAL_* */
+static int
+insert_section(struct reply_info* rep, size_t num_rrsets, uint16_t* num_rrs,
+	sldns_buffer* pkt, size_t rrsets_before, time_t timenow, 
+	struct regional* region, struct compress_tree_node** tree,
+	sldns_pkt_section s, uint16_t qtype, int dnssec, size_t rr_offset)
+{
+	int r;
+	size_t i, setstart;
+	*num_rrs = 0;
+	if(s != LDNS_SECTION_ADDITIONAL) {
+		if(s == LDNS_SECTION_ANSWER && qtype == LDNS_RR_TYPE_ANY)
+			dnssec = 1; /* include all types in ANY answer */
+	  	for(i=0; i<num_rrsets; i++) {
+			setstart = sldns_buffer_position(pkt);
+			if((r=packed_rrset_encode(rep->rrsets[rrsets_before+i], 
+				pkt, num_rrs, timenow, region, 1, 1, tree,
+				s, qtype, dnssec, rr_offset))
+				!= RETVAL_OK) {
+				/* Bad, but if due to size must set TC bit */
+				/* trim off the rrset neatly. */
+				sldns_buffer_set_position(pkt, setstart);
+				return r;
+			}
+		}
+	} else {
+	  	for(i=0; i<num_rrsets; i++) {
+			setstart = sldns_buffer_position(pkt);
+			if((r=packed_rrset_encode(rep->rrsets[rrsets_before+i], 
+				pkt, num_rrs, timenow, region, 1, 0, tree,
+				s, qtype, dnssec, rr_offset))
+				!= RETVAL_OK) {
+				sldns_buffer_set_position(pkt, setstart);
+				return r;
+			}
+		}
+		if(dnssec)
+	  	  for(i=0; i<num_rrsets; i++) {
+			setstart = sldns_buffer_position(pkt);
+			if((r=packed_rrset_encode(rep->rrsets[rrsets_before+i], 
+				pkt, num_rrs, timenow, region, 0, 1, tree,
+				s, qtype, dnssec, rr_offset))
+				!= RETVAL_OK) {
+				sldns_buffer_set_position(pkt, setstart);
+				return r;
+			}
+		  }
+	}
+	return RETVAL_OK;
+}
+
+/** store query section in wireformat buffer, return RETVAL */
+static int
+insert_query(struct query_info* qinfo, struct compress_tree_node** tree, 
+	sldns_buffer* buffer, struct regional* region)
+{
+	if(sldns_buffer_remaining(buffer) < 
+		qinfo->qname_len+sizeof(uint16_t)*2)
+		return RETVAL_TRUNC; /* buffer too small */
+	/* the query is the first name inserted into the tree */
+	if(!compress_tree_store(qinfo->qname, 
+		dname_count_labels(qinfo->qname), 
+		sldns_buffer_position(buffer), region, NULL, tree))
+		return RETVAL_OUTMEM;
+	if(sldns_buffer_current(buffer) == qinfo->qname)
+		sldns_buffer_skip(buffer, (ssize_t)qinfo->qname_len);
+	else	sldns_buffer_write(buffer, qinfo->qname, qinfo->qname_len);
+	sldns_buffer_write_u16(buffer, qinfo->qtype);
+	sldns_buffer_write_u16(buffer, qinfo->qclass);
+	return RETVAL_OK;
+}
+
+static int
+positive_answer(struct reply_info* rep, uint16_t qtype) {
+	size_t i;
+	if (FLAGS_GET_RCODE(rep->flags) != LDNS_RCODE_NOERROR)
+		return 0;
+
+	for(i=0;i<rep->an_numrrsets; i++) {
+		if(ntohs(rep->rrsets[i]->rk.type) == qtype) {
+			/* in case it is a wildcard with DNSSEC, there will
+			 * be NSEC/NSEC3 records in the authority section
+			 * that we cannot remove */
+			for(i=rep->an_numrrsets; i<rep->an_numrrsets+
+				rep->ns_numrrsets; i++) {
+				if(ntohs(rep->rrsets[i]->rk.type) ==
+					LDNS_RR_TYPE_NSEC ||
+				   ntohs(rep->rrsets[i]->rk.type) ==
+				   	LDNS_RR_TYPE_NSEC3)
+					return 0;
+			}
+			return 1;
+		}
+	}
+	return 0;
+}
+
+int 
+reply_info_encode(struct query_info* qinfo, struct reply_info* rep, 
+	uint16_t id, uint16_t flags, sldns_buffer* buffer, time_t timenow, 
+	struct regional* region, uint16_t udpsize, int dnssec)
+{
+	uint16_t ancount=0, nscount=0, arcount=0;
+	struct compress_tree_node* tree = 0;
+	int r;
+	size_t rr_offset; 
+
+	sldns_buffer_clear(buffer);
+	if(udpsize < sldns_buffer_limit(buffer))
+		sldns_buffer_set_limit(buffer, udpsize);
+	if(sldns_buffer_remaining(buffer) < LDNS_HEADER_SIZE)
+		return 0;
+
+	sldns_buffer_write(buffer, &id, sizeof(uint16_t));
+	sldns_buffer_write_u16(buffer, flags);
+	sldns_buffer_write_u16(buffer, rep->qdcount);
+	/* set an, ns, ar counts to zero in case of small packets */
+	sldns_buffer_write(buffer, "\000\000\000\000\000\000", 6);
+
+	/* insert query section */
+	if(rep->qdcount) {
+		if((r=insert_query(qinfo, &tree, buffer, region)) != 
+			RETVAL_OK) {
+			if(r == RETVAL_TRUNC) {
+				/* create truncated message */
+				sldns_buffer_write_u16_at(buffer, 4, 0);
+				LDNS_TC_SET(sldns_buffer_begin(buffer));
+				sldns_buffer_flip(buffer);
+				return 1;
+			}
+			return 0;
+		}
+	}
+	/* roundrobin offset. using query id for random number.  With ntohs
+	 * for different roundrobins for sequential id client senders. */
+	rr_offset = RRSET_ROUNDROBIN?ntohs(id):0;
+
+	/* insert answer section */
+	if((r=insert_section(rep, rep->an_numrrsets, &ancount, buffer, 
+		0, timenow, region, &tree, LDNS_SECTION_ANSWER, qinfo->qtype, 
+		dnssec, rr_offset)) != RETVAL_OK) {
+		if(r == RETVAL_TRUNC) {
+			/* create truncated message */
+			sldns_buffer_write_u16_at(buffer, 6, ancount);
+			LDNS_TC_SET(sldns_buffer_begin(buffer));
+			sldns_buffer_flip(buffer);
+			return 1;
+		}
+		return 0;
+	}
+	sldns_buffer_write_u16_at(buffer, 6, ancount);
+
+	/* if response is positive answer, auth/add sections are not required */
+	if( ! (MINIMAL_RESPONSES && positive_answer(rep, qinfo->qtype)) ) {
+		/* insert auth section */
+		if((r=insert_section(rep, rep->ns_numrrsets, &nscount, buffer, 
+			rep->an_numrrsets, timenow, region, &tree,
+			LDNS_SECTION_AUTHORITY, qinfo->qtype,
+			dnssec, rr_offset)) != RETVAL_OK) {
+			if(r == RETVAL_TRUNC) {
+				/* create truncated message */
+				sldns_buffer_write_u16_at(buffer, 8, nscount);
+				LDNS_TC_SET(sldns_buffer_begin(buffer));
+				sldns_buffer_flip(buffer);
+				return 1;
+			}
+			return 0;
+		}
+		sldns_buffer_write_u16_at(buffer, 8, nscount);
+
+		/* insert add section */
+		if((r=insert_section(rep, rep->ar_numrrsets, &arcount, buffer, 
+			rep->an_numrrsets + rep->ns_numrrsets, timenow, region, 
+			&tree, LDNS_SECTION_ADDITIONAL, qinfo->qtype, 
+			dnssec, rr_offset)) != RETVAL_OK) {
+			if(r == RETVAL_TRUNC) {
+				/* no need to set TC bit, this is the additional */
+				sldns_buffer_write_u16_at(buffer, 10, arcount);
+				sldns_buffer_flip(buffer);
+				return 1;
+			}
+			return 0;
+		}
+		sldns_buffer_write_u16_at(buffer, 10, arcount);
+	}
+	sldns_buffer_flip(buffer);
+	return 1;
+}
+
+uint16_t
+calc_edns_field_size(struct edns_data* edns)
+{
+	if(!edns || !edns->edns_present) 
+		return 0;
+	/* domain root '.' + type + class + ttl + rdatalen(=0) */
+	return 1 + 2 + 2 + 4 + 2;
+}
+
+void
+attach_edns_record(sldns_buffer* pkt, struct edns_data* edns)
+{
+	size_t len;
+	if(!edns || !edns->edns_present)
+		return;
+	/* inc additional count */
+	sldns_buffer_write_u16_at(pkt, 10,
+		sldns_buffer_read_u16_at(pkt, 10) + 1);
+	len = sldns_buffer_limit(pkt);
+	sldns_buffer_clear(pkt);
+	sldns_buffer_set_position(pkt, len);
+	/* write EDNS record */
+	sldns_buffer_write_u8(pkt, 0); /* '.' label */
+	sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_OPT); /* type */
+	sldns_buffer_write_u16(pkt, edns->udp_size); /* class */
+	sldns_buffer_write_u8(pkt, edns->ext_rcode); /* ttl */
+	sldns_buffer_write_u8(pkt, edns->edns_version);
+	sldns_buffer_write_u16(pkt, edns->bits);
+	sldns_buffer_write_u16(pkt, 0); /* rdatalen */
+	sldns_buffer_flip(pkt);
+}
+
+int 
+reply_info_answer_encode(struct query_info* qinf, struct reply_info* rep, 
+	uint16_t id, uint16_t qflags, sldns_buffer* pkt, time_t timenow,
+	int cached, struct regional* region, uint16_t udpsize, 
+	struct edns_data* edns, int dnssec, int secure)
+{
+	uint16_t flags;
+	int attach_edns = 1;
+
+	if(!cached || rep->authoritative) {
+		/* original flags, copy RD and CD bits from query. */
+		flags = rep->flags | (qflags & (BIT_RD|BIT_CD)); 
+	} else {
+		/* remove AA bit, copy RD and CD bits from query. */
+		flags = (rep->flags & ~BIT_AA) | (qflags & (BIT_RD|BIT_CD)); 
+	}
+	if(secure && (dnssec || (qflags&BIT_AD)))
+		flags |= BIT_AD;
+	log_assert(flags & BIT_QR); /* QR bit must be on in our replies */
+	if(udpsize < LDNS_HEADER_SIZE)
+		return 0;
+	if(udpsize < LDNS_HEADER_SIZE + calc_edns_field_size(edns)) {
+		/* packet too small to contain edns, omit it. */
+		attach_edns = 0;
+	} else {
+		/* reserve space for edns record */
+		udpsize -= calc_edns_field_size(edns);
+	}
+
+	if(!reply_info_encode(qinf, rep, id, flags, pkt, timenow, region,
+		udpsize, dnssec)) {
+		log_err("reply encode: out of memory");
+		return 0;
+	}
+	if(attach_edns)
+		attach_edns_record(pkt, edns);
+	return 1;
+}
+
+void 
+qinfo_query_encode(sldns_buffer* pkt, struct query_info* qinfo)
+{
+	uint16_t flags = 0; /* QUERY, NOERROR */
+	sldns_buffer_clear(pkt);
+	log_assert(sldns_buffer_remaining(pkt) >= 12+255+4/*max query*/);
+	sldns_buffer_skip(pkt, 2); /* id done later */
+	sldns_buffer_write_u16(pkt, flags);
+	sldns_buffer_write_u16(pkt, 1); /* query count */
+	sldns_buffer_write(pkt, "\000\000\000\000\000\000", 6); /* counts */
+	sldns_buffer_write(pkt, qinfo->qname, qinfo->qname_len);
+	sldns_buffer_write_u16(pkt, qinfo->qtype);
+	sldns_buffer_write_u16(pkt, qinfo->qclass);
+	sldns_buffer_flip(pkt);
+}
+
+void 
+error_encode(sldns_buffer* buf, int r, struct query_info* qinfo,
+	uint16_t qid, uint16_t qflags, struct edns_data* edns)
+{
+	uint16_t flags;
+
+	sldns_buffer_clear(buf);
+	sldns_buffer_write(buf, &qid, sizeof(uint16_t));
+	flags = (uint16_t)(BIT_QR | BIT_RA | r); /* QR and retcode*/
+	flags |= (qflags & (BIT_RD|BIT_CD)); /* copy RD and CD bit */
+	sldns_buffer_write_u16(buf, flags);
+	if(qinfo) flags = 1;
+	else	flags = 0;
+	sldns_buffer_write_u16(buf, flags);
+	flags = 0;
+	sldns_buffer_write(buf, &flags, sizeof(uint16_t));
+	sldns_buffer_write(buf, &flags, sizeof(uint16_t));
+	sldns_buffer_write(buf, &flags, sizeof(uint16_t));
+	if(qinfo) {
+		if(sldns_buffer_current(buf) == qinfo->qname)
+			sldns_buffer_skip(buf, (ssize_t)qinfo->qname_len);
+		else	sldns_buffer_write(buf, qinfo->qname, qinfo->qname_len);
+		sldns_buffer_write_u16(buf, qinfo->qtype);
+		sldns_buffer_write_u16(buf, qinfo->qclass);
+	}
+	sldns_buffer_flip(buf);
+	if(edns) {
+		struct edns_data es = *edns;
+		es.edns_version = EDNS_ADVERTISED_VERSION;
+		es.udp_size = EDNS_ADVERTISED_SIZE;
+		es.ext_rcode = 0;
+		es.bits &= EDNS_DO;
+		if(sldns_buffer_limit(buf) + calc_edns_field_size(&es) >
+			edns->udp_size)
+			return;
+		attach_edns_record(buf, &es);
+	}
+}