network_cmds-596.100.2.tar.gz

[apple/network_cmds.git] / unbound / util / data / msgreply.c

/*
 * 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 "ldns/sbuffer.h"
#include "ldns/wire2str.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;

/** 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;
        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, 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(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->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, msg->an_rrsets, msg->ns_rrsets, msg->ar_rrsets, 
                msg->rrset_count, sec_status_unchecked);
        if(!*rep)
                return 0;
        return 1;
}

/** allocate (special) rrset keys, return 0 on error */
static int
repinfo_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;
}

/** 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)
{
        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(*rr_ttl < MIN_TTL)
                *rr_ttl = MIN_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) {
                                memmove(to, sldns_buffer_current(pkt), len);
                                to += len;
                                sldns_buffer_skip(pkt, (ssize_t)len);
                                log_assert(len <= pkt_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))
                        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))
                        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 = 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);
        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(!repinfo_alloc_rrset_keys(*rep, alloc, region))
                return 0;
        if(!parse_copy_decompress(pkt, msg, *rep, region))
                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;
        *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)) != 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;
        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_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);
        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_t 
query_info_hash(struct query_info *q, uint16_t flags)
{
        hashvalue_t 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_t 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, sizeof(e->key));
        lock_protect(&e->entry.lock, &e->entry.hash, sizeof(e->entry.hash) +
                sizeof(e->entry.key) + 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->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(!repinfo_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)) {
                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_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 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 = rep->rrsets[0]->rk.dname;
        size_t snamelen = rep->rrsets[0]->rk.dname_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;
}