resolver.c

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/*
 * resolver.c
 *
 * resolver implementation
 *
 * a Net::DNS like library for C
 *
 * (c) NLnet Labs, 2004-2006
 *
 * See the file LICENSE for the license
 */
 
#include <ldns/config.h>
 
#include <ldns/ldns.h>
#include <strings.h>
 
/* Access function for reading
 * and setting the different Resolver
 * options */
 
/* read */
uint16_t
ldns_resolver_port(const ldns_resolver *r)
{
        return r->_port;
}
 
ldns_rdf *
ldns_resolver_source(const ldns_resolver *r)
{
        return r->_source;
}
 
uint16_t
ldns_resolver_edns_udp_size(const ldns_resolver *r)
{
                return r->_edns_udp_size;
}
 
uint8_t
ldns_resolver_retry(const ldns_resolver *r)
{
        return r->_retry;
}
 
uint8_t
ldns_resolver_retrans(const ldns_resolver *r)
{
        return r->_retrans;
}
 
bool
ldns_resolver_fallback(const ldns_resolver *r)
{
        return r->_fallback;
}
 
uint8_t
ldns_resolver_ip6(const ldns_resolver *r)
{
        return r->_ip6;
}
 
bool
ldns_resolver_recursive(const ldns_resolver *r)
{
        return r->_recursive;
}
 
bool
ldns_resolver_debug(const ldns_resolver *r)
{
        return r->_debug;
}
 
bool
ldns_resolver_dnsrch(const ldns_resolver *r)
{
        return r->_dnsrch;
}
 
bool
ldns_resolver_fail(const ldns_resolver *r)
{
        return r->_fail;
}
 
bool
ldns_resolver_defnames(const ldns_resolver *r)
{
        return r->_defnames;
}
 
ldns_rdf *
ldns_resolver_domain(const ldns_resolver *r)
{
        return r->_domain;
}
 
ldns_rdf **
ldns_resolver_searchlist(const ldns_resolver *r)
{
        return r->_searchlist;
}
 
ldns_rdf **
ldns_resolver_nameservers(const ldns_resolver *r)
{
        return r->_nameservers;
}
 
size_t
ldns_resolver_nameserver_count(const ldns_resolver *r)
{
        return r->_nameserver_count;
}
 
bool
ldns_resolver_dnssec(const ldns_resolver *r)
{
        return r->_dnssec;
}
 
bool
ldns_resolver_dnssec_cd(const ldns_resolver *r)
{
        return r->_dnssec_cd;
}
 
ldns_rr_list *
ldns_resolver_dnssec_anchors(const ldns_resolver *r)
{
    return r->_dnssec_anchors;
}
 
bool
ldns_resolver_trusted_key(const ldns_resolver *r, ldns_rr_list * keys, ldns_rr_list * trusted_keys)
{
  size_t i;
  bool result = false;
 
  ldns_rr_list * trust_anchors;
  ldns_rr * cur_rr;
 
  if (!r || !keys) { return false; }
 
  trust_anchors = ldns_resolver_dnssec_anchors(r);
 
  if (!trust_anchors) { return false; }
 
  for (i = 0; i < ldns_rr_list_rr_count(keys); i++) {
 
    cur_rr = ldns_rr_list_rr(keys, i);
    if (ldns_rr_list_contains_rr(trust_anchors, cur_rr)) {
      if (trusted_keys) { ldns_rr_list_push_rr(trusted_keys, cur_rr); }
      result = true;
    }
  }
 
  return result;
}
 
bool
ldns_resolver_igntc(const ldns_resolver *r)
{
        return r->_igntc;
}
 
bool
ldns_resolver_usevc(const ldns_resolver *r)
{
        return r->_usevc;
}
 
size_t *
ldns_resolver_rtt(const ldns_resolver *r)
{
        return r->_rtt;
}
 
size_t
ldns_resolver_nameserver_rtt(const ldns_resolver *r, size_t pos)
{
        size_t *rtt;
 
        assert(r != NULL);
 
        rtt = ldns_resolver_rtt(r);
 
        if (pos >= ldns_resolver_nameserver_count(r)) {
                /* error ?*/
                return 0;
        } else {
                return rtt[pos];
        }
 
}
 
struct timeval
ldns_resolver_timeout(const ldns_resolver *r)
{
        return r->_timeout;
}
 
const char *
ldns_resolver_tsig_keyname(const ldns_resolver *r)
{
        return r->_tsig_keyname;
}
 
const char *
ldns_resolver_tsig_algorithm(const ldns_resolver *r)
{
        return r->_tsig_algorithm;
}
 
const char *
ldns_resolver_tsig_keydata(const ldns_resolver *r)
{
        return r->_tsig_keydata;
}
 
bool
ldns_resolver_random(const ldns_resolver *r)
{
        return r->_random;
}
 
size_t
ldns_resolver_searchlist_count(const ldns_resolver *r)
{
        return r->_searchlist_count;
}
 
/* write */
void
ldns_resolver_set_port(ldns_resolver *r, uint16_t p)
{
        r->_port = p;
}
 
void
ldns_resolver_set_source(ldns_resolver *r, ldns_rdf *s)
{
        r->_source = s;
}
 
ldns_rdf *
ldns_resolver_pop_nameserver(ldns_resolver *r)
{
        ldns_rdf **nameservers;
        ldns_rdf *pop;
        size_t ns_count;
        size_t *rtt;
 
        assert(r != NULL);
 
        ns_count = ldns_resolver_nameserver_count(r);
        nameservers = ldns_resolver_nameservers(r);
        rtt = ldns_resolver_rtt(r);
        if (ns_count == 0 || !nameservers) {
                return NULL;
        }
 
        pop = nameservers[ns_count - 1];
 
        if (ns_count == 1) {
                LDNS_FREE(nameservers);
                LDNS_FREE(rtt);
 
                ldns_resolver_set_nameservers(r, NULL);
                ldns_resolver_set_rtt(r, NULL);
        } else {
                nameservers = LDNS_XREALLOC(nameservers, ldns_rdf *, 
                                (ns_count - 1));
                rtt = LDNS_XREALLOC(rtt, size_t, (ns_count - 1));
 
                ldns_resolver_set_nameservers(r, nameservers);
                ldns_resolver_set_rtt(r, rtt);
        }
        /* decr the count */
        ldns_resolver_dec_nameserver_count(r);
        return pop;
}
 
ldns_status
ldns_resolver_push_nameserver(ldns_resolver *r, const ldns_rdf *n)
{
        ldns_rdf **nameservers;
        size_t ns_count;
        size_t *rtt;
 
        if (ldns_rdf_get_type(n) != LDNS_RDF_TYPE_A &&
                        ldns_rdf_get_type(n) != LDNS_RDF_TYPE_AAAA) {
                return LDNS_STATUS_ERR;
        }
 
        ns_count = ldns_resolver_nameserver_count(r);
        nameservers = ldns_resolver_nameservers(r);
        rtt = ldns_resolver_rtt(r);
 
        /* make room for the next one */
        if (ns_count == 0) {
                nameservers = LDNS_XMALLOC(ldns_rdf *, 1);
        } else {
                nameservers = LDNS_XREALLOC(nameservers, ldns_rdf *, (ns_count + 1));
        }
        if(!nameservers)
                return LDNS_STATUS_MEM_ERR;
 
        /* set the new value in the resolver */
        ldns_resolver_set_nameservers(r, nameservers);
 
        /* don't forget the rtt */
        if (ns_count == 0) {
                rtt = LDNS_XMALLOC(size_t, 1);
        } else {
                rtt = LDNS_XREALLOC(rtt, size_t, (ns_count + 1));
        }
        if(!rtt)
                return LDNS_STATUS_MEM_ERR;
 
        /* slide n in its slot. */
        /* we clone it here, because then we can free the original
         * rr's where it stood */
        nameservers[ns_count] = ldns_rdf_clone(n);
        rtt[ns_count] = LDNS_RESOLV_RTT_MIN;
        ldns_resolver_incr_nameserver_count(r);
        ldns_resolver_set_rtt(r, rtt);
        return LDNS_STATUS_OK;
}
 
ldns_status
ldns_resolver_push_nameserver_rr(ldns_resolver *r, const ldns_rr *rr)
{
        ldns_rdf *address;
        if ((!rr) || (ldns_rr_get_type(rr) != LDNS_RR_TYPE_A &&
                        ldns_rr_get_type(rr) != LDNS_RR_TYPE_AAAA)) {
                return LDNS_STATUS_ERR;
        }
        address = ldns_rr_rdf(rr, 0); /* extract the ip number */
        if (address) {
                return ldns_resolver_push_nameserver(r, address);
        } else {
                return LDNS_STATUS_ERR;
        }
}
 
ldns_status
ldns_resolver_push_nameserver_rr_list(ldns_resolver *r, const ldns_rr_list *rrlist)
{
        ldns_rr *rr;
        ldns_status stat;
        size_t i;
 
        stat = LDNS_STATUS_OK;
        if (rrlist) {
                for(i = 0; i < ldns_rr_list_rr_count(rrlist); i++) {
                        rr = ldns_rr_list_rr(rrlist, i);
                        if (ldns_resolver_push_nameserver_rr(r, rr) != LDNS_STATUS_OK) {
                                stat = LDNS_STATUS_ERR;
                                break;
                        }
                }
                return stat;
        } else {
                return LDNS_STATUS_ERR;
        }
}
 
void
ldns_resolver_set_edns_udp_size(ldns_resolver *r, uint16_t s)
{
                r->_edns_udp_size = s;
}
 
void
ldns_resolver_set_recursive(ldns_resolver *r, bool re)
{
        r->_recursive = re;
}
 
void
ldns_resolver_set_dnssec(ldns_resolver *r, bool d)
{
        r->_dnssec = d;
}
 
void
ldns_resolver_set_dnssec_cd(ldns_resolver *r, bool d)
{
        r->_dnssec_cd = d;
}
 
void
ldns_resolver_set_dnssec_anchors(ldns_resolver *r, ldns_rr_list * l)
{
  r->_dnssec_anchors = l;
}
 
ldns_status
ldns_resolver_push_dnssec_anchor(ldns_resolver *r, ldns_rr *rr)
{
  ldns_rr_list * trust_anchors;
 
  if ((!rr) || (ldns_rr_get_type(rr) != LDNS_RR_TYPE_DNSKEY &&
                ldns_rr_get_type(rr) != LDNS_RR_TYPE_DS)) {
 
    return LDNS_STATUS_ERR;
  }
 
  if (!(trust_anchors = ldns_resolver_dnssec_anchors(r))) { /* Initialize */
    trust_anchors = ldns_rr_list_new();
    ldns_resolver_set_dnssec_anchors(r, trust_anchors);
  }
 
  return (ldns_rr_list_push_rr(trust_anchors, ldns_rr_clone(rr))) ? LDNS_STATUS_OK : LDNS_STATUS_ERR;
}
 
void
ldns_resolver_set_igntc(ldns_resolver *r, bool i)
{
        r->_igntc = i;
}
 
void
ldns_resolver_set_usevc(ldns_resolver *r, bool vc)
{
        r->_usevc = vc;
}
 
void
ldns_resolver_set_debug(ldns_resolver *r, bool d)
{
        r->_debug = d;
}
 
void
ldns_resolver_set_ip6(ldns_resolver *r, uint8_t ip6)
{
        r->_ip6 = ip6;
}
 
void
ldns_resolver_set_fail(ldns_resolver *r, bool f)
{
        r->_fail =f;
}
 
static void
ldns_resolver_set_searchlist_count(ldns_resolver *r, size_t c)
{
        r->_searchlist_count = c;
}
 
void
ldns_resolver_set_nameserver_count(ldns_resolver *r, size_t c)
{
        r->_nameserver_count = c;
}
 
void
ldns_resolver_set_dnsrch(ldns_resolver *r, bool d)
{
        r->_dnsrch = d;
}
 
void
ldns_resolver_set_retry(ldns_resolver *r, uint8_t retry)
{
        r->_retry = retry;
}
 
void
ldns_resolver_set_retrans(ldns_resolver *r, uint8_t retrans)
{
        r->_retrans = retrans;
}
 
void
ldns_resolver_set_fallback(ldns_resolver *r, bool fallback)
{
        r->_fallback = fallback;
}
 
void
ldns_resolver_set_nameservers(ldns_resolver *r, ldns_rdf **n)
{
        r->_nameservers = n;
}
 
void
ldns_resolver_set_defnames(ldns_resolver *r, bool d)
{
        r->_defnames = d;
}
 
void
ldns_resolver_set_rtt(ldns_resolver *r, size_t *rtt)
{
        r->_rtt = rtt;
}
 
void
ldns_resolver_set_nameserver_rtt(ldns_resolver *r, size_t pos, size_t value)
{
        size_t *rtt;
 
        assert(r != NULL);
 
        rtt = ldns_resolver_rtt(r);
 
        if (pos >= ldns_resolver_nameserver_count(r)) {
                /* error ?*/
        } else {
                rtt[pos] = value;
        }
 
}
 
void
ldns_resolver_incr_nameserver_count(ldns_resolver *r)
{
        size_t c;
 
        c = ldns_resolver_nameserver_count(r);
        ldns_resolver_set_nameserver_count(r, ++c);
}
 
void
ldns_resolver_dec_nameserver_count(ldns_resolver *r)
{
        size_t c;
 
        c = ldns_resolver_nameserver_count(r);
        if (c == 0) {
                return;
        } else {
                ldns_resolver_set_nameserver_count(r, --c);
        }
}
 
void
ldns_resolver_set_domain(ldns_resolver *r, ldns_rdf *d)
{
        r->_domain = d;
}
 
void
ldns_resolver_set_timeout(ldns_resolver *r, struct timeval timeout)
{
        r->_timeout.tv_sec = timeout.tv_sec;
        r->_timeout.tv_usec = timeout.tv_usec;
}
 
void
ldns_resolver_push_searchlist(ldns_resolver *r, ldns_rdf *d)
{
        ldns_rdf **searchlist;
        size_t list_count;
 
        if (ldns_rdf_get_type(d) != LDNS_RDF_TYPE_DNAME) {
                return;
        }
 
        list_count = ldns_resolver_searchlist_count(r);
        searchlist = ldns_resolver_searchlist(r);
 
        searchlist = LDNS_XREALLOC(searchlist, ldns_rdf *, (list_count + 1));
        if (searchlist) {
                r->_searchlist = searchlist;
 
                searchlist[list_count] = ldns_rdf_clone(d);
                ldns_resolver_set_searchlist_count(r, list_count + 1);
        } /* no way to report mem err */
}
 
void
ldns_resolver_set_tsig_keyname(ldns_resolver *r, const char *tsig_keyname)
{
        LDNS_FREE(r->_tsig_keyname);
        r->_tsig_keyname = strdup(tsig_keyname);
}
 
void
ldns_resolver_set_tsig_algorithm(ldns_resolver *r, const char *tsig_algorithm)
{
        LDNS_FREE(r->_tsig_algorithm);
        r->_tsig_algorithm = strdup(tsig_algorithm);
}
 
void
ldns_resolver_set_tsig_keydata(ldns_resolver *r, const char *tsig_keydata)
{
        LDNS_FREE(r->_tsig_keydata);
        r->_tsig_keydata = strdup(tsig_keydata);
}
 
void
ldns_resolver_set_random(ldns_resolver *r, bool b)
{
        r->_random = b;
}
 
/* more sophisticated functions */
ldns_resolver *
ldns_resolver_new(void)
{
        ldns_resolver *r;
 
        r = LDNS_MALLOC(ldns_resolver);
        if (!r) {
                return NULL;
        }
 
        r->_searchlist = NULL;
        r->_nameservers = NULL;
        r->_rtt = NULL;
 
        /* defaults are filled out */
        ldns_resolver_set_searchlist_count(r, 0);
        ldns_resolver_set_nameserver_count(r, 0);
        ldns_resolver_set_usevc(r, 0);
        ldns_resolver_set_port(r, LDNS_PORT);
        ldns_resolver_set_domain(r, NULL);
        ldns_resolver_set_defnames(r, false);
        ldns_resolver_set_retry(r, 3);
        ldns_resolver_set_retrans(r, 2);
        ldns_resolver_set_fallback(r, true);
        ldns_resolver_set_fail(r, false);
        ldns_resolver_set_edns_udp_size(r, 0);
        ldns_resolver_set_dnssec(r, false);
        ldns_resolver_set_dnssec_cd(r, false);
        ldns_resolver_set_dnssec_anchors(r, NULL);
        ldns_resolver_set_ip6(r, LDNS_RESOLV_INETANY);
        ldns_resolver_set_igntc(r, false);
        ldns_resolver_set_recursive(r, false);
        ldns_resolver_set_dnsrch(r, true);
        ldns_resolver_set_source(r, NULL);
        ldns_resolver_set_ixfr_serial(r, 0);
 
        /* randomize the nameserver to be queried
         * when there are multiple
         */
        ldns_resolver_set_random(r, true);
 
        ldns_resolver_set_debug(r, 0);
 
        r->_timeout.tv_sec = LDNS_DEFAULT_TIMEOUT_SEC;
        r->_timeout.tv_usec = LDNS_DEFAULT_TIMEOUT_USEC;
 
        r->_socket = -1;
        r->_axfr_soa_count = 0;
        r->_axfr_i = 0;
        r->_cur_axfr_pkt = NULL;
 
        r->_tsig_keyname = NULL;
        r->_tsig_keydata = NULL;
        r->_tsig_algorithm = NULL;
        return r;
}
 
ldns_resolver *
ldns_resolver_clone(ldns_resolver *src)
{
        ldns_resolver *dst;
        size_t i;
 
        assert(src != NULL);
 
        if (!(dst = LDNS_MALLOC(ldns_resolver))) return NULL;
        (void) memcpy(dst, src, sizeof(ldns_resolver));
 
        if (dst->_searchlist_count == 0)
                dst->_searchlist = NULL;
        else {
                if (!(dst->_searchlist =
                    LDNS_XMALLOC(ldns_rdf *, dst->_searchlist_count)))
                        goto error;
                for (i = 0; i < dst->_searchlist_count; i++)
                        if (!(dst->_searchlist[i] =
                            ldns_rdf_clone(src->_searchlist[i]))) {
                                dst->_searchlist_count = i;
                                goto error_searchlist;
                        }
        }
        if (dst->_nameserver_count == 0) {
                dst->_nameservers = NULL;
                dst->_rtt = NULL;
        } else {
                if (!(dst->_nameservers =
                    LDNS_XMALLOC(ldns_rdf *, dst->_nameserver_count)))
                        goto error_searchlist;
                for (i = 0; i < dst->_nameserver_count; i++)
                        if (!(dst->_nameservers[i] =
                            ldns_rdf_clone(src->_nameservers[i]))) {
                                dst->_nameserver_count = i;
                                goto error_nameservers;
                        }
                if (!(dst->_rtt =
                    LDNS_XMALLOC(size_t, dst->_nameserver_count)))
                        goto error_nameservers;
                (void) memcpy(dst->_rtt, src->_rtt,
                    sizeof(size_t) * dst->_nameserver_count);
        }
        if (dst->_domain && (!(dst->_domain = ldns_rdf_clone(src->_domain))))
                goto error_rtt;
 
        if (dst->_tsig_keyname &&
            (!(dst->_tsig_keyname = strdup(src->_tsig_keyname))))
                goto error_domain;
 
        if (dst->_tsig_keydata &&
            (!(dst->_tsig_keydata = strdup(src->_tsig_keydata))))
                goto error_tsig_keyname;
 
        if (dst->_tsig_algorithm &&
            (!(dst->_tsig_algorithm = strdup(src->_tsig_algorithm))))
                goto error_tsig_keydata;
 
        if (dst->_cur_axfr_pkt &&
            (!(dst->_cur_axfr_pkt = ldns_pkt_clone(src->_cur_axfr_pkt))))
                goto error_tsig_algorithm;
 
        if (dst->_dnssec_anchors &&
            (!(dst->_dnssec_anchors=ldns_rr_list_clone(src->_dnssec_anchors))))
                goto error_cur_axfr_pkt;
 
        return dst;
 
error_cur_axfr_pkt:
        ldns_pkt_free(dst->_cur_axfr_pkt);
error_tsig_algorithm:
        LDNS_FREE(dst->_tsig_algorithm);
error_tsig_keydata:
        LDNS_FREE(dst->_tsig_keydata);
error_tsig_keyname:
        LDNS_FREE(dst->_tsig_keyname);
error_domain:
        ldns_rdf_deep_free(dst->_domain);
error_rtt:
        LDNS_FREE(dst->_rtt);
error_nameservers:
        for (i = 0; i < dst->_nameserver_count; i++)
                ldns_rdf_deep_free(dst->_nameservers[i]);
        LDNS_FREE(dst->_nameservers);
error_searchlist:
        for (i = 0; i < dst->_searchlist_count; i++)
                ldns_rdf_deep_free(dst->_searchlist[i]);
        LDNS_FREE(dst->_searchlist);
error:
        LDNS_FREE(dst);
        return NULL;
}
 
 
ldns_status
ldns_resolver_new_frm_fp(ldns_resolver **res, FILE *fp)
{
        return ldns_resolver_new_frm_fp_l(res, fp, NULL);
}
 
ldns_status
ldns_resolver_new_frm_fp_l(ldns_resolver **res, FILE *fp, int *line_nr)
{
        ldns_resolver *r = NULL;
        const char *keyword[LDNS_RESOLV_KEYWORDS];
        char word[LDNS_MAX_LINELEN + 1];
        int8_t expect;
        uint8_t i;
        ldns_rdf *tmp;
#ifdef HAVE_SSL
        ldns_rr *tmp_rr;
#endif
        ssize_t gtr, bgtr;
        ldns_buffer *b;
        int lnr = 0;
        FILE* myfp = fp;
        if(!line_nr) line_nr = &lnr;
 
        if(!fp) {
                myfp = fopen(LDNS_RESOLV_CONF, "r");
                if(!myfp)
                        return LDNS_STATUS_FILE_ERR;
        }
 
        /* do this better
         * expect =
         * 0: keyword
         * 1: default domain dname
         * 2: NS aaaa or a record
         */
 
        /* recognized keywords */
        keyword[LDNS_RESOLV_NAMESERVER] = "nameserver";
        keyword[LDNS_RESOLV_DEFDOMAIN] = "domain";
        keyword[LDNS_RESOLV_SEARCH] = "search";
        /* these two are read but not used atm TODO */
        keyword[LDNS_RESOLV_SORTLIST] = "sortlist";
        keyword[LDNS_RESOLV_OPTIONS] = "options";
        keyword[LDNS_RESOLV_ANCHOR] = "anchor";
 
        r = ldns_resolver_new();
        if (!r) {
                if(!fp) fclose(myfp);
                return LDNS_STATUS_MEM_ERR;
        }
 
        gtr = 1;
        word[0] = 0;
        expect = LDNS_RESOLV_KEYWORD;
        while (gtr > 0) {
                switch(expect) {
                        case LDNS_RESOLV_KEYWORD:
                                /* keyword */
                                gtr = ldns_fget_token_l_resolv_conf(myfp, word, LDNS_PARSE_NORMAL, 0, line_nr);
                                if (gtr != 0) {
                                        for(i = 0; i < LDNS_RESOLV_KEYWORDS; i++) {
                                                if (strcasecmp(keyword[i], word) == 0) {
                                                        /* chosen the keyword and
                                                         * expect values carefully
                                                         */
                                                        expect = i;
                                                        break;
                                                }
                                        }
                                        /* no keyword recognized */
                                        if (expect == LDNS_RESOLV_KEYWORD) {
                                                /* skip line */
                                                /*
                                                ldns_resolver_deep_free(r);
                                                if(!fp) fclose(myfp);
                                                return LDNS_STATUS_SYNTAX_KEYWORD_ERR;
                                                */
                                        }
                                }
                                break;
                        case LDNS_RESOLV_DEFDOMAIN:
                                /* default domain dname */
                                gtr = ldns_fget_token_l_resolv_conf(myfp, word, LDNS_PARSE_NORMAL, 0, line_nr);
                                if (gtr == 0) {
                                        if(!fp) fclose(myfp);
                                        ldns_resolver_deep_free(r);
                                        return LDNS_STATUS_SYNTAX_MISSING_VALUE_ERR;
                                }
                                tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, word);
                                if (!tmp) {
                                        if(!fp) fclose(myfp);
                                        ldns_resolver_deep_free(r);
                                        return LDNS_STATUS_SYNTAX_DNAME_ERR;
                                }
 
                                /* DOn't free, because we copy the pointer */
                                ldns_resolver_set_domain(r, tmp);
                                expect = LDNS_RESOLV_KEYWORD;
                                break;
                        case LDNS_RESOLV_NAMESERVER:
                                /* NS aaaa or a record */
                                gtr = ldns_fget_token_l_resolv_conf(myfp, word, LDNS_PARSE_NORMAL, 0, line_nr);
                                if (gtr == 0) {
                                        if(!fp) fclose(myfp);
                                        ldns_resolver_deep_free(r);
                                        return LDNS_STATUS_SYNTAX_MISSING_VALUE_ERR;
                                }
                                if(strchr(word, '%')) {
                                        /* snip off interface labels,
                                         * fe80::222:19ff:fe31:4222%eth0 */
                                        strchr(word, '%')[0]=0;
                                }
                                tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_AAAA, word);
                                if (!tmp) {
                                        /* try ip4 */
                                        tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_A, word);
                                }
                                /* could not parse it, exit */
                                if (!tmp) {
                                        ldns_resolver_deep_free(r);
                                        if(!fp) fclose(myfp);
                                        return LDNS_STATUS_SYNTAX_ERR;
                                }
                                (void)ldns_resolver_push_nameserver(r, tmp);
                                ldns_rdf_deep_free(tmp);
                                expect = LDNS_RESOLV_KEYWORD;
                                break;
                        case LDNS_RESOLV_SEARCH:
                                /* search list domain dname */
                                gtr = ldns_fget_token_l_resolv_conf(myfp, word, LDNS_PARSE_SKIP_SPACE, 0, line_nr);
                                b = LDNS_MALLOC(ldns_buffer);
                                if(!b) {
                                        ldns_resolver_deep_free(r);
                                        if(!fp) fclose(myfp);
                                        return LDNS_STATUS_MEM_ERR;
                                }
 
                                ldns_buffer_new_frm_data(b, word, (size_t) gtr);
                                if(ldns_buffer_status(b) != LDNS_STATUS_OK) {
                                        LDNS_FREE(b);
                                        ldns_resolver_deep_free(r);
                                        if(!fp) fclose(myfp);
                                        return LDNS_STATUS_MEM_ERR;
                                }
                                bgtr = ldns_bget_token(b, word, LDNS_PARSE_NORMAL, (size_t) gtr + 1);
                                while (bgtr > 0) {
                                        gtr -= bgtr;
                                        tmp = ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, word);
                                        if (!tmp) {
                                                ldns_resolver_deep_free(r);
                                                ldns_buffer_free(b);
                                                if(!fp) fclose(myfp);
                                                return LDNS_STATUS_SYNTAX_DNAME_ERR;
                                        }
 
                                        ldns_resolver_push_searchlist(r, tmp);
 
                                        ldns_rdf_deep_free(tmp);
                                        bgtr = ldns_bget_token(b, word, LDNS_PARSE_NORMAL,
                                            (size_t) gtr + 1);
                                }
                                ldns_buffer_free(b);
                                if (expect != LDNS_RESOLV_KEYWORD) {
                                        gtr = 1;
                                        expect = LDNS_RESOLV_KEYWORD;
                                }
                                break;
                        case LDNS_RESOLV_SORTLIST:
                                gtr = ldns_fget_token_l_resolv_conf(myfp, word, LDNS_PARSE_SKIP_SPACE, 0, line_nr);
                                /* sortlist not implemented atm */
                                expect = LDNS_RESOLV_KEYWORD;
                                break;
                        case LDNS_RESOLV_OPTIONS:
                                gtr = ldns_fget_token_l_resolv_conf(myfp, word, LDNS_PARSE_SKIP_SPACE, 0, line_nr);
                                /* options not implemented atm */
                                expect = LDNS_RESOLV_KEYWORD;
                                break;
                        case LDNS_RESOLV_ANCHOR:
                                /* a file containing a DNSSEC trust anchor */
                                gtr = ldns_fget_token_l_resolv_conf(myfp, word, LDNS_PARSE_NORMAL, 0, line_nr);
                                if (gtr == 0) {
                                        ldns_resolver_deep_free(r);
                                        if(!fp) fclose(myfp);
                                        return LDNS_STATUS_SYNTAX_MISSING_VALUE_ERR;
                                }
#ifdef HAVE_SSL
                                tmp_rr = ldns_read_anchor_file(word);
                                (void) ldns_resolver_push_dnssec_anchor(r, tmp_rr);
                                ldns_rr_free(tmp_rr);
#endif
                                expect = LDNS_RESOLV_KEYWORD;
                                break;
                }
        }
 
        if(!fp)
                fclose(myfp);
 
        if (res) {
                *res = r;
                return LDNS_STATUS_OK;
        } else {
                ldns_resolver_deep_free(r);
                return LDNS_STATUS_NULL;
        }
}
 
ldns_status
ldns_resolver_new_frm_file(ldns_resolver **res, const char *filename)
{
        ldns_resolver *r;
        FILE *fp;
        ldns_status s;
 
        if (!filename) {
                fp = fopen(LDNS_RESOLV_CONF, "r");
 
        } else {
                fp = fopen(filename, "r");
        }
        if (!fp) {
                return LDNS_STATUS_FILE_ERR;
        }
 
        s = ldns_resolver_new_frm_fp(&r, fp);
        fclose(fp);
        if (s == LDNS_STATUS_OK) {
                if (res) {
                        *res = r;
                        return LDNS_STATUS_OK;
                } else  {
                        ldns_resolver_free(r);
                        return LDNS_STATUS_NULL;
                }
        }
        return s;
}
 
void
ldns_resolver_free(ldns_resolver *res)
{
        LDNS_FREE(res);
}
 
void
ldns_resolver_deep_free(ldns_resolver *res)
{
        size_t i;
 
        if (res) {
                close_socket(res->_socket);
 
                if (res->_searchlist) {
                        for (i = 0; i < ldns_resolver_searchlist_count(res); i++) {
                                ldns_rdf_deep_free(res->_searchlist[i]);
                        }
                        LDNS_FREE(res->_searchlist);
                }
                if (res->_nameservers) {
                        for (i = 0; i < res->_nameserver_count; i++) {
                                ldns_rdf_deep_free(res->_nameservers[i]);
                        }
                        LDNS_FREE(res->_nameservers);
                }
                if (ldns_resolver_domain(res)) {
                        ldns_rdf_deep_free(ldns_resolver_domain(res));
                }
                if (res->_tsig_keyname) {
                        LDNS_FREE(res->_tsig_keyname);
                }
                if (res->_tsig_keydata) {
                        LDNS_FREE(res->_tsig_keydata);
                }
                if (res->_tsig_algorithm) {
                        LDNS_FREE(res->_tsig_algorithm);
                }
 
                if (res->_cur_axfr_pkt) {
                        ldns_pkt_free(res->_cur_axfr_pkt);
                }
 
                if (res->_rtt) {
                        LDNS_FREE(res->_rtt);
                }
                if (res->_dnssec_anchors) {
                        ldns_rr_list_deep_free(res->_dnssec_anchors);
                }
                LDNS_FREE(res);
        }
}
 
ldns_status
ldns_resolver_search_status(ldns_pkt** pkt,
                ldns_resolver *r, const  ldns_rdf *name,
                ldns_rr_type t, ldns_rr_class c, uint16_t flags)
{
        ldns_rdf *new_name;
        ldns_rdf **search_list;
        size_t i;
        ldns_status s = LDNS_STATUS_OK;
        ldns_rdf root_dname = { 1, LDNS_RDF_TYPE_DNAME, (void *)"" };
 
        if (ldns_dname_absolute(name)) {
                /* query as-is */
                return ldns_resolver_query_status(pkt, r, name, t, c, flags);
        } else if (ldns_resolver_dnsrch(r)) {
                search_list = ldns_resolver_searchlist(r);
                for (i = 0; i <= ldns_resolver_searchlist_count(r); i++) {
                        if (i == ldns_resolver_searchlist_count(r)) {
                                new_name = ldns_dname_cat_clone(name,
                                                &root_dname);
                        } else {
                                new_name = ldns_dname_cat_clone(name,
                                                search_list[i]);
                        }
 
                        s = ldns_resolver_query_status(pkt, r,
                                        new_name, t, c, flags);
                        ldns_rdf_deep_free(new_name);
 
                        if (pkt && *pkt) {
                                if (s == LDNS_STATUS_OK && 
                                                ldns_pkt_get_rcode(*pkt) ==
                                                LDNS_RCODE_NOERROR) {
 
                                        return LDNS_STATUS_OK;
                                }
                                ldns_pkt_free(*pkt);
                                *pkt = NULL;
                        }
                }
        }
        return s;
}
 
ldns_pkt *
ldns_resolver_search(const ldns_resolver *r,const  ldns_rdf *name,
        ldns_rr_type t, ldns_rr_class c, uint16_t flags)
{
        ldns_pkt* pkt = NULL;
        if (ldns_resolver_search_status(&pkt, (ldns_resolver *)r,
                                name, t, c, flags) != LDNS_STATUS_OK) {
                ldns_pkt_free(pkt);
                return NULL;
        }
        return pkt;
}
 
ldns_status
ldns_resolver_query_status(ldns_pkt** pkt,
                ldns_resolver *r, const ldns_rdf *name,
                ldns_rr_type t, ldns_rr_class c, uint16_t flags)
{
        ldns_rdf *newname;
        ldns_status status;
 
        if (!ldns_resolver_defnames(r) || !ldns_resolver_domain(r)) {
                return ldns_resolver_send(pkt, r, name, t, c, flags);
        }
 
        newname = ldns_dname_cat_clone(name, ldns_resolver_domain(r));
        if (!newname) {
                return LDNS_STATUS_MEM_ERR;
        }
        status = ldns_resolver_send(pkt, r, newname, t, c, flags);
        ldns_rdf_free(newname);
        return status;
}
 
ldns_pkt *
ldns_resolver_query(const ldns_resolver *r, const ldns_rdf *name,
        ldns_rr_type t, ldns_rr_class c, uint16_t flags)
{
        ldns_pkt* pkt = NULL;
        if (ldns_resolver_query_status(&pkt, (ldns_resolver *)r,
                                name, t, c, flags) != LDNS_STATUS_OK) {
                ldns_pkt_free(pkt);
                return NULL;
        }
        return pkt;
}
 
static size_t *
ldns_resolver_backup_rtt(ldns_resolver *r)
{
        size_t *new_rtt;
        size_t *old_rtt = ldns_resolver_rtt(r);
 
        if (old_rtt && ldns_resolver_nameserver_count(r)) {
                new_rtt = LDNS_XMALLOC(size_t
                                , ldns_resolver_nameserver_count(r));
                if (!new_rtt) return NULL;
                memcpy(new_rtt, old_rtt, sizeof(size_t)
                                * ldns_resolver_nameserver_count(r));
                ldns_resolver_set_rtt(r, new_rtt);
                return old_rtt;
        }
        return NULL;
}
 
static void
ldns_resolver_restore_rtt(ldns_resolver *r, size_t *old_rtt)
{
        size_t *cur_rtt = ldns_resolver_rtt(r);
 
        if (cur_rtt) {
                LDNS_FREE(cur_rtt);
        }
        ldns_resolver_set_rtt(r, old_rtt);
}
 
ldns_status
ldns_resolver_send_pkt(ldns_pkt **answer, ldns_resolver *r,
                                   ldns_pkt *query_pkt)
{
        ldns_pkt *answer_pkt = NULL;
        ldns_status stat = LDNS_STATUS_OK;
        size_t *rtt;
 
        stat = ldns_send(&answer_pkt, (ldns_resolver *)r, query_pkt);
        if (stat != LDNS_STATUS_OK) {
                if(answer_pkt) {
                        ldns_pkt_free(answer_pkt);
                        answer_pkt = NULL;
                }
        } else {
                /* if tc=1 fall back to EDNS and/or TCP */
                /* check for tcp first (otherwise we don't care about tc=1) */
                if (!ldns_resolver_usevc(r) && ldns_resolver_fallback(r)) {
                        if (ldns_pkt_tc(answer_pkt)) {
                                /* was EDNS0 set? */
                                if (ldns_pkt_edns_udp_size(query_pkt) == 0) {
                                        ldns_pkt_set_edns_udp_size(query_pkt
                                                        , 4096);
                                        ldns_pkt_free(answer_pkt);
                                        answer_pkt = NULL;
                                        /* Nameservers should not become 
                                         * unreachable because fragments are
                                         * dropped (network error). We might
                                         * still have success with TCP.
                                         * Therefore maintain reachability
                                         * statuses of the nameservers by
                                         * backup and restore the rtt list.
                                         */
                                        rtt = ldns_resolver_backup_rtt(r);
                                        stat = ldns_send(&answer_pkt, r
                                                        , query_pkt);
                                        ldns_resolver_restore_rtt(r, rtt);
                                }
                                /* either way, if it is still truncated, use TCP */
                                if (stat != LDNS_STATUS_OK ||
                                    ldns_pkt_tc(answer_pkt)) {
                                        ldns_resolver_set_usevc(r, true);
                                        ldns_pkt_free(answer_pkt);
                                        answer_pkt = NULL;
                                        stat = ldns_send(&answer_pkt, r, query_pkt);
                                        ldns_resolver_set_usevc(r, false);
                                }
                        }
                }
        }
 
        if (answer && answer_pkt) {
                *answer = answer_pkt;
        }
 
        return stat;
}
 
ldns_status
ldns_resolver_prepare_query_pkt(ldns_pkt **query_pkt, ldns_resolver *r,
                                const ldns_rdf *name, ldns_rr_type t,
                                ldns_rr_class c, uint16_t flags)
{
        struct timeval now;
        ldns_rr* soa = NULL;
 
        /* prepare a question pkt from the parameters
         * and then send this */
        if (t == LDNS_RR_TYPE_IXFR) {
                ldns_rdf *owner_rdf;
                ldns_rdf *mname_rdf;
                ldns_rdf *rname_rdf;
                ldns_rdf *serial_rdf;
                ldns_rdf *refresh_rdf;
                ldns_rdf *retry_rdf;
                ldns_rdf *expire_rdf;
                ldns_rdf *minimum_rdf;
                soa = ldns_rr_new();
 
                if (!soa) {
                        return LDNS_STATUS_ERR;
                }
                owner_rdf = ldns_rdf_clone(name);
                if (!owner_rdf) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                }
                ldns_rr_set_owner(soa, owner_rdf);
                ldns_rr_set_type(soa, LDNS_RR_TYPE_SOA);
                ldns_rr_set_class(soa, c);
                ldns_rr_set_question(soa, false);
                if (ldns_str2rdf_dname(&mname_rdf, ".") != LDNS_STATUS_OK) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                } else  ldns_rr_push_rdf(soa, mname_rdf);
                if (ldns_str2rdf_dname(&rname_rdf, ".") != LDNS_STATUS_OK) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                } else  ldns_rr_push_rdf(soa, rname_rdf);
                serial_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, ldns_resolver_get_ixfr_serial(r));
                if (!serial_rdf) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                } else  ldns_rr_push_rdf(soa, serial_rdf);
                refresh_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
                if (!refresh_rdf) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                } else  ldns_rr_push_rdf(soa, refresh_rdf);
                retry_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
                if (!retry_rdf) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                } else  ldns_rr_push_rdf(soa, retry_rdf);
                expire_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
                if (!expire_rdf) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                } else  ldns_rr_push_rdf(soa, expire_rdf);
                minimum_rdf = ldns_native2rdf_int32(LDNS_RDF_TYPE_INT32, 0);
                if (!minimum_rdf) {
                        ldns_rr_free(soa);
                        return LDNS_STATUS_ERR;
                } else  ldns_rr_push_rdf(soa, minimum_rdf);
 
                *query_pkt = ldns_pkt_ixfr_request_new(ldns_rdf_clone(name),
                        c, flags, soa);
        } else {
                *query_pkt = ldns_pkt_query_new(ldns_rdf_clone(name), t, c, flags);
        }
        if (!*query_pkt) {
                ldns_rr_free(soa);
                return LDNS_STATUS_ERR;
        }
 
        /* set DO bit if necessary */
        if (ldns_resolver_dnssec(r)) {
                if (ldns_resolver_edns_udp_size(r) == 0) {
                        ldns_resolver_set_edns_udp_size(r, 4096);
                }
                ldns_pkt_set_edns_do(*query_pkt, true);
                if (ldns_resolver_dnssec_cd(r) || (flags & LDNS_CD)) {
                        ldns_pkt_set_cd(*query_pkt, true);
                }
        }
 
        /* transfer the udp_edns_size from the resolver to the packet */
        if (ldns_resolver_edns_udp_size(r) != 0) {
                ldns_pkt_set_edns_udp_size(*query_pkt, ldns_resolver_edns_udp_size(r));
        }
 
        /* set the timestamp */
        now.tv_sec = time(NULL);
        now.tv_usec = 0;
        ldns_pkt_set_timestamp(*query_pkt, now);
 
 
        if (ldns_resolver_debug(r)) {
                ldns_pkt_print(stdout, *query_pkt);
        }
 
        /* only set the id if it is not set yet */
        if (ldns_pkt_id(*query_pkt) == 0) {
                ldns_pkt_set_random_id(*query_pkt);
        }
 
        return LDNS_STATUS_OK;
}
 
ldns_status
ldns_resolver_send(ldns_pkt **answer, ldns_resolver *r, const ldns_rdf *name,
                ldns_rr_type t, ldns_rr_class c, uint16_t flags)
{
        ldns_pkt *query_pkt;
        ldns_pkt *answer_pkt;
        ldns_status status;
 
        assert(r != NULL);
        assert(name != NULL);
 
        answer_pkt = NULL;
 
        /* do all the preprocessing here, then fire of an query to
         * the network */
 
        if (0 == t) {
                t= LDNS_RR_TYPE_A;
        }
        if (0 == c) {
                c= LDNS_RR_CLASS_IN;
        }
        if (0 == ldns_resolver_nameserver_count(r)) {
                return LDNS_STATUS_RES_NO_NS;
        }
        if (ldns_rdf_get_type(name) != LDNS_RDF_TYPE_DNAME) {
                return LDNS_STATUS_RES_QUERY;
        }
 
        status = ldns_resolver_prepare_query_pkt(&query_pkt, r, name,
                                                 t, c, flags);
        if (status != LDNS_STATUS_OK) {
                return status;
        }
 
        /* if tsig values are set, tsign it */
        /* TODO: make last 3 arguments optional too? maybe make complete
                 rr instead of separate values in resolver (and packet)
          Jelte
          should this go in pkt_prepare?
        */
        if (ldns_resolver_tsig_keyname(r) && ldns_resolver_tsig_keydata(r)) {
#ifdef HAVE_SSL
                status = ldns_pkt_tsig_sign(query_pkt,
                                            ldns_resolver_tsig_keyname(r),
                                            ldns_resolver_tsig_keydata(r),
                                            300, ldns_resolver_tsig_algorithm(r), NULL);
                if (status != LDNS_STATUS_OK) {
                        ldns_pkt_free(query_pkt);
                        return LDNS_STATUS_CRYPTO_TSIG_ERR;
                }
#else
                ldns_pkt_free(query_pkt);
                return LDNS_STATUS_CRYPTO_TSIG_ERR;
#endif /* HAVE_SSL */
        }
 
        status = ldns_resolver_send_pkt(&answer_pkt, r, query_pkt);
        ldns_pkt_free(query_pkt);
 
        /* allows answer to be NULL when not interested in return value */
        if (answer) {
                *answer = answer_pkt;
        }
        return status;
}
 
ldns_rr *
ldns_axfr_next(ldns_resolver *resolver)
{
        ldns_rr *cur_rr;
        uint8_t *packet_wire;
        size_t packet_wire_size;
        ldns_status status;
 
        /* check if start() has been called */
        if (!resolver || resolver->_socket == -1) {
                return NULL;
        }
 
        if (resolver->_cur_axfr_pkt) {
                if (resolver->_axfr_i == ldns_pkt_ancount(resolver->_cur_axfr_pkt)) {
                        ldns_pkt_free(resolver->_cur_axfr_pkt);
                        resolver->_cur_axfr_pkt = NULL;
                        return ldns_axfr_next(resolver);
                }
                cur_rr = ldns_rr_clone(ldns_rr_list_rr(
                                        ldns_pkt_answer(resolver->_cur_axfr_pkt),
                                        resolver->_axfr_i));
                resolver->_axfr_i++;
                if (ldns_rr_get_type(cur_rr) == LDNS_RR_TYPE_SOA) {
                        resolver->_axfr_soa_count++;
                        if (resolver->_axfr_soa_count >= 2) {
 
                                close_socket(resolver->_socket);
 
                                ldns_pkt_free(resolver->_cur_axfr_pkt);
                                resolver->_cur_axfr_pkt = NULL;
                        }
                }
                return cur_rr;
        } else {
               packet_wire = ldns_tcp_read_wire_timeout(resolver->_socket, &packet_wire_size, resolver->_timeout);
                if(!packet_wire)
                        return NULL;
 
                status = ldns_wire2pkt(&resolver->_cur_axfr_pkt, packet_wire,
                                     packet_wire_size);
                LDNS_FREE(packet_wire);
 
                resolver->_axfr_i = 0;
                if (status != LDNS_STATUS_OK) {
                        /* TODO: make status return type of this function (...api change) */
#ifdef STDERR_MSGS
                        fprintf(stderr, "Error parsing rr during AXFR: %s\n", ldns_get_errorstr_by_id(status));
#endif
 
                        /* we must now also close the socket, otherwise subsequent uses of the
                           same resolver structure will fail because the link is still open or
                           in an undefined state */
 
                        close_socket(resolver->_socket);
 
                        return NULL;
                } else if (ldns_pkt_get_rcode(resolver->_cur_axfr_pkt) != 0) {
#ifdef STDERR_MSGS
                        ldns_lookup_table *rcode = ldns_lookup_by_id(
                                ldns_rcodes,(int) ldns_pkt_get_rcode(
                                resolver->_cur_axfr_pkt));
                        if (rcode) {
                                fprintf(stderr, "Error in AXFR: %s\n", 
                                                rcode->name);
                        } else {
                                fprintf(stderr, "Error in AXFR: %d\n", 
                                                (int) ldns_pkt_get_rcode(
                                                resolver->_cur_axfr_pkt));
                        }
#endif
 
                        /* we must now also close the socket, otherwise subsequent uses of the
                           same resolver structure will fail because the link is still open or
                           in an undefined state */
 
                        close_socket(resolver->_socket);
 
                        return NULL;
                } else {
                        return ldns_axfr_next(resolver);
                }
 
        }
 
}
 
/* this function is needed to abort a transfer that is in progress;
 * without it an aborted transfer will lead to the AXFR code in the
 * library staying in an indetermined state because the socket for the
 * AXFR is never closed
 */
void
ldns_axfr_abort(ldns_resolver *resolver)
{
        /* Only abort if an actual AXFR is in progress */
        if (resolver->_socket != -1)
        {
#ifndef USE_WINSOCK
                close(resolver->_socket);
#else
                closesocket(resolver->_socket);
#endif
                resolver->_socket = -1;
        }
}
 
bool
ldns_axfr_complete(const ldns_resolver *res)
{
        /* complete when soa count is 2? */
        return res->_axfr_soa_count == 2;
}
 
ldns_pkt *
ldns_axfr_last_pkt(const ldns_resolver *res)
{
        return res->_cur_axfr_pkt;
}
 
void
ldns_resolver_set_ixfr_serial(ldns_resolver *r, uint32_t serial)
{
        r->_serial = serial;
}
 
uint32_t
ldns_resolver_get_ixfr_serial(const ldns_resolver *res)
{
        return res->_serial;
}
 
 
/* random isn't really that good */
void
ldns_resolver_nameservers_randomize(ldns_resolver *r)
{
        uint16_t i, j;
        ldns_rdf **ns, *tmpns;
        size_t *rtt, tmprtt;
 
        /* should I check for ldns_resolver_random?? */
        assert(r != NULL);
 
        ns = ldns_resolver_nameservers(r);
        rtt = ldns_resolver_rtt(r);
        for (i = 0; i < ldns_resolver_nameserver_count(r); i++) {
                j = ldns_get_random() % ldns_resolver_nameserver_count(r);
                tmpns = ns[i];
                ns[i] = ns[j];
                ns[j] = tmpns;
                tmprtt = rtt[i];
                rtt[i] = rtt[j];
                rtt[j] = tmprtt;
        }
        ldns_resolver_set_nameservers(r, ns);
}