bin/dig/dighost.c

	dighost.c revision eb305df466969c846723a8298a6770de2316aeb9
/*
 * Copyright (C) 2000  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/* $Id: dighost.c,v 1.63 2000/06/29 07:43:46 explorer Exp $ */

/*
 * Notice to programmers:  Do not use this code as an example of how to
 * use the ISC library to perform DNS lookups.  Dig and Host both operate
 * on the request level, since they allow fine-tuning of output and are
 * intended as debugging tools.  As a result, they perform many of the
 * functions which could be better handled using the dns_resolver
 * functions in most applications.
 */

#include <config.h>
#include <stdlib.h>
#include <unistd.h>
#if defined(HAVE_ADDRINFO) && defined(HAVE_GETADDRINFO)
#include <netdb.h>
#include <string.h>
#else
extern int h_errno;
#endif

#include <dns/message.h>
#include <dns/name.h>
#include <dns/rdata.h>
#include <dns/rdataclass.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/rdatastruct.h>
#include <dns/rdatatype.h>
#include <dns/result.h>
#include <dns/tsig.h>
#include <dst/dst.h>
#include <isc/app.h>
#include <isc/base64.h>
#include <isc/entropy.h>
#include <isc/lang.h>
#include <isc/lex.h>
#include <isc/netdb.h>
#include <isc/result.h>
#include <isc/string.h>
#include <isc/task.h>
#include <isc/timer.h>
#include <isc/types.h>
#include <isc/util.h>

#include <dig/dig.h>

ISC_LIST(dig_lookup_t) lookup_list;
ISC_LIST(dig_server_t) server_list;
ISC_LIST(dig_searchlist_t) search_list;

isc_boolean_t have_ipv6 = ISC_FALSE, specified_source = ISC_FALSE,
    free_now = ISC_FALSE, show_details = ISC_FALSE, usesearch=ISC_TRUE,
    qr = ISC_FALSE, is_dst_up = ISC_FALSE;
in_port_t port = 53;
unsigned int timeout = 5;
isc_mem_t *mctx = NULL;
isc_taskmgr_t *taskmgr = NULL;
isc_task_t *global_task = NULL;
isc_timermgr_t *timermgr = NULL;
isc_socketmgr_t *socketmgr = NULL;
isc_sockaddr_t bind_address;
isc_sockaddr_t bind_any;
char *rootspace[BUFSIZE];
isc_buffer_t rootbuf;
int sendcount = 0;
int sockcount = 0;
int ndots = -1;
int tries = 3;
int lookup_counter = 0;
char fixeddomain[MXNAME]="";
int exitcode = 9;
char keynametext[MXNAME];
char keysecret[MXNAME]="";
dns_name_t keyname;
dns_tsig_keyring_t *keyring = NULL;
isc_buffer_t *namebuf = NULL;
dns_tsigkey_t *key = NULL;
isc_boolean_t validated = ISC_TRUE;
isc_entropy_t *entp = NULL;

extern isc_boolean_t isc_mem_debugging;
isc_boolean_t debugging = ISC_FALSE;

static void
cancel_lookup(dig_lookup_t *lookup);

static int
count_dots(char *string) {
    char *s;
    int i=0;

    s = string;
    while (*s != 0) {
        if (*s == '.')
            i++;
        s++;
    }
    return (i);
}

static void
hex_dump(isc_buffer_t *b) {
    unsigned int len;
    isc_region_t r;

    isc_buffer_remainingregion(b, &r);

    printf("Printing a buffer with length %d\n", r.length);
    for (len = 0 ; len < r.length ; len++) {
        printf("%02x ", r.base[len]);
        if (len != 0 && len % 16 == 0)
            printf("\n");
    }
    if (len % 16 != 0)
        printf("\n");
}


void
fatal(const char *format, ...) {
    va_list args;

    va_start(args, format);
    vfprintf(stderr, format, args);
    va_end(args);
    fprintf(stderr, "\n");
    if (exitcode == 0)
        exitcode = 8;
#ifdef NEVER
    dighost_shutdown();
    free_lists(exitcode);
    if (mctx != NULL) {
        if (isc_mem_debugging)
            isc_mem_stats(mctx, stderr);
        isc_mem_destroy(&mctx);
    }
#endif
    exit(exitcode);
}

void
debug(const char *format, ...) {
    va_list args;

    if (debugging) {
        va_start(args, format);
        vfprintf(stderr, format, args);
        va_end(args);
        fprintf(stderr, "\n");
    }
}

void
check_result(isc_result_t result, const char *msg) {
    if (result != ISC_R_SUCCESS) {
        exitcode = 1;
        fatal("%s: %s", msg, isc_result_totext(result));
    }
}

isc_boolean_t
isclass(char *text) {
    /* Tests if a field is a class, without needing isc libs
     * initialized.  This list will have to be manually kept in
     * sync with what the libs support.
     */
    const char *classlist[] = {"in", "hs", "chaos"};
    const int numclasses = 3;
    int i;

    for (i = 0; i < numclasses; i++)
        if (strcasecmp(text, classlist[i]) == 0)
            return ISC_TRUE;

    return ISC_FALSE;
}

isc_boolean_t
istype(char *text) {
    /* Tests if a field is a type, without needing isc libs
     * initialized.  This list will have to be manually kept in
     *  sync with what the libs support.
     */
    const char *typelist[] = {"a", "ns", "md", "mf", "cname",
                  "soa", "mb", "mg", "mr", "null",
                  "wks", "ptr", "hinfo", "minfo",
                  "mx", "txt", "rp", "afsdb",
                  "x25", "isdn", "rt", "nsap",
                  "nsap_ptr", "sig", "key", "px",
                  "gpos", "aaaa", "loc", "nxt",
                  "srv", "naptr", "kx", "cert",
                  "a6", "dname", "opt", "unspec",
                  "tkey", "tsig", "axfr", "any"};
    const int numtypes = 42;
    int i;

    for (i = 0; i < numtypes; i++) {
        if (strcasecmp(text, typelist[i]) == 0)
            return ISC_TRUE;
    }
    return ISC_FALSE;
}

dig_lookup_t
*requeue_lookup(dig_lookup_t *lookold, isc_boolean_t servers) {
    dig_lookup_t *looknew;
    dig_server_t *s, *srv;

    debug("requeue_lookup()");

    if (free_now)
        return(ISC_R_SUCCESS);

    lookup_counter++;
    if (lookup_counter > LOOKUP_LIMIT)
        fatal ("Too many lookups.");
    looknew = isc_mem_allocate
        (mctx, sizeof(struct dig_lookup));
    if (looknew == NULL)
        fatal ("Memory allocation failure in %s:%d",
               __FILE__, __LINE__);
    looknew->pending = ISC_FALSE;
    strncpy (looknew->textname, lookold-> textname, MXNAME);
    strncpy (looknew->rttext, lookold-> rttext, 32);
    strncpy (looknew->rctext, lookold-> rctext, 32);
    looknew->namespace[0]=0;
    looknew->sendspace[0]=0;
    looknew->sendmsg=NULL;
    looknew->name=NULL;
    looknew->oname=NULL;
    looknew->timer = NULL;
    looknew->xfr_q = NULL;
    looknew->doing_xfr = lookold->doing_xfr;
    looknew->ixfr_serial = lookold->ixfr_serial;
    looknew->defname = lookold->defname;
    looknew->trace = lookold->trace;
    looknew->trace_root = lookold->trace_root;
    looknew->identify = lookold->identify;
    looknew->udpsize = lookold->udpsize;
    looknew->recurse = lookold->recurse;
    looknew->aaonly = lookold->aaonly;
    looknew->adflag = lookold->adflag;
    looknew->cdflag = lookold->cdflag;
    looknew->ns_search_only = lookold->ns_search_only;
    looknew->origin = NULL;
    looknew->querysig = NULL;
    looknew->retries = tries;
    looknew->nsfound = 0;
    looknew->tcp_mode = lookold->tcp_mode;
    looknew->comments = lookold->comments;
    looknew->stats = lookold->stats;
    looknew->section_question = lookold->section_question;
    looknew->section_answer = lookold->section_answer;
    looknew->section_authority = lookold->section_authority;
    looknew->section_additional = lookold->section_additional;
    looknew->new_search = ISC_FALSE;
    ISC_LIST_INIT(looknew->my_server_list);
    ISC_LIST_INIT(looknew->q);

    looknew->use_my_server_list = ISC_FALSE;
    if (servers) {
        looknew->use_my_server_list = lookold->use_my_server_list;
        if (looknew->use_my_server_list) {
            s = ISC_LIST_HEAD(lookold->my_server_list);
            while (s != NULL) {
                srv = isc_mem_allocate (mctx, sizeof(struct
                                dig_server));
                if (srv == NULL)
                    fatal("Memory allocation failure "
                          "in %s:%d", __FILE__, __LINE__);
                strncpy(srv->servername, s->servername,
                    MXNAME);
                ISC_LIST_ENQUEUE(looknew->my_server_list, srv,
                         link);
                s = ISC_LIST_NEXT(s, link);
            }
        }
    }
    debug ("Before insertion, init@%p "
           "-> %p, new@%p "
           "-> %p", lookold,
           lookold->link.next,
           looknew, looknew->
           link.next);
    ISC_LIST_INSERTAFTER(lookup_list, lookold, looknew, link);
    debug ("After insertion, init -> "
           "%p, new = %p, "
           "new -> %p", lookold,
           looknew, looknew->
           link.next);
    return (looknew);
}

void
setup_system(void) {
    char rcinput[MXNAME];
    FILE *fp;
    char *ptr;
    dig_server_t *srv;
    dig_searchlist_t *search;
    dig_lookup_t *l;
    isc_boolean_t get_servers;
    isc_result_t result;
    isc_buffer_t secretsrc;
    isc_buffer_t secretbuf;
    int secretsize;
    unsigned char *secretstore;
    isc_lex_t *lex = NULL;
    isc_stdtime_t now;

    debug ("setup_system()");

    if (fixeddomain[0]!=0) {
        debug("Using fixed domain %s", fixeddomain);
        search = isc_mem_allocate( mctx, sizeof(struct dig_server));
        if (search == NULL)
            fatal("Memory allocation failure in %s:%d",
                  __FILE__, __LINE__);
        strncpy(search->origin, fixeddomain, MXNAME - 1);
        ISC_LIST_PREPEND(search_list, search, link);
    }

    free_now = ISC_FALSE;
    get_servers = ISC_TF(server_list.head == NULL);
    fp = fopen (RESOLVCONF, "r");
    if (fp != NULL) {
        while (fgets(rcinput, MXNAME, fp) != 0) {
            ptr = strtok (rcinput, " \t\r\n");
            if (ptr != NULL) {
                if (get_servers &&
                    strcasecmp(ptr, "nameserver") == 0) {
                    debug ("Got a nameserver line");
                    ptr = strtok (NULL, " \t\r\n");
                    if (ptr != NULL) {
                        srv = isc_mem_allocate(mctx,
                           sizeof(struct dig_server));
                        if (srv == NULL)
                            fatal("Memory "
                                  "allocation "
                                  "failure in "
                                  "%s:%d",
                                  __FILE__,
                                  __LINE__);
                            strncpy((char *)srv->
                                servername,
                                ptr,
                                MXNAME - 1);
                            ISC_LIST_APPEND
                                (server_list,
                                 srv, link);
                    }
                } else if (strcasecmp(ptr, "options") == 0) {
                    ptr = strtok(NULL, " \t\r\n");
                    if (ptr != NULL) {
                        if ((strncasecmp(ptr, "ndots:",
                                6) == 0) &&
                            (ndots == -1)) {
                            ndots = atoi(
                                  &ptr[6]);
                            debug ("ndots is "
                                   "%d.",
                                   ndots);
                        }
                    }
                } else if ((strcasecmp(ptr, "search") == 0)
                       && usesearch){
                    while ((ptr = strtok(NULL, " \t\r\n"))
                           != NULL) {
                        search = isc_mem_allocate(
                           mctx, sizeof(struct
                                dig_server));
                        if (search == NULL)
                            fatal("Memory "
                                  "allocation "
                                  "failure in %s:"
                                  "%d", __FILE__,
                                  __LINE__);
                        strncpy(search->
                            origin,
                            ptr,
                            MXNAME - 1);
                        ISC_LIST_APPEND
                            (search_list,
                             search,
                             link);
                    }
                } else if ((strcasecmp(ptr, "domain") == 0) &&
                       (fixeddomain[0] == 0 )){
                    while ((ptr = strtok(NULL, " \t\r\n"))
                           != NULL) {
                        search = isc_mem_allocate(
                           mctx, sizeof(struct
                                dig_server));
                        if (search == NULL)
                            fatal("Memory "
                                  "allocation "
                                  "failure in %s:"
                                  "%d", __FILE__,
                                  __LINE__);
                        strncpy(search->
                            origin,
                            ptr,
                            MXNAME - 1);
                        ISC_LIST_PREPEND
                            (search_list,
                             search,
                             link);
                    }
                }

            }
        }
        fclose (fp);
    }

    if (ndots == -1)
        ndots = 1;

    if (server_list.head == NULL) {
        srv = isc_mem_allocate(mctx, sizeof(dig_server_t));
        if (srv == NULL)
            fatal("Memory allocation failure");
        strcpy(srv->servername, "127.0.0.1");
        ISC_LIST_APPEND(server_list, srv, link);
    }

    for (l = ISC_LIST_HEAD(lookup_list) ;
         l != NULL;
         l = ISC_LIST_NEXT(l, link) ) {
         l -> origin = ISC_LIST_HEAD(search_list);
         }

    if (keysecret[0] != 0) {
        debug("keyring");
        result = dns_tsigkeyring_create(mctx, &keyring);
        check_result(result, "dns_tsigkeyring_create");
        debug("buffer");
        result = isc_buffer_allocate(mctx, &namebuf, MXNAME);
        check_result(result, "isc_buffer_allocate");
        debug("name");
        dns_name_init(&keyname, NULL);
        check_result(result, "dns_name_init");
        isc_buffer_putstr(namebuf, keynametext);
        secretsize = strlen(keysecret) * 3 / 4;
        debug("secretstore");
        secretstore = isc_mem_get(mctx, secretsize);
        ENSURE (secretstore != NULL);
        isc_buffer_init(&secretsrc, keysecret, strlen(keysecret));
        isc_buffer_add(&secretsrc, strlen(keysecret));
        isc_buffer_init(&secretbuf, secretstore, secretsize);
        debug("lex");
        result = isc_lex_create(mctx, strlen(keysecret), &lex);
        check_result(result, "isc_lex_create");
        result = isc_lex_openbuffer(lex, &secretsrc);
        check_result(result, "isc_lex_openbuffer");
        result = isc_base64_tobuffer(lex, &secretbuf, -1);
        if (result != ISC_R_SUCCESS) {
            printf (";; Couldn't create key %s: %s\n",
                keynametext, isc_result_totext(result));
            isc_lex_close(lex);
            isc_lex_destroy(&lex);
            goto SYSSETUP_FAIL;
        }
        secretsize = isc_buffer_usedlength(&secretbuf);
        debug("close");
        isc_lex_close(lex);
        isc_lex_destroy(&lex);
        isc_stdtime_get(&now);

        debug("namefromtext");
        result = dns_name_fromtext(&keyname, namebuf,
                       dns_rootname, ISC_FALSE,
                       namebuf);
        if (result != ISC_R_SUCCESS) {
            printf (";; Couldn't create key %s: %s\n",
                keynametext, dns_result_totext(result));
            goto SYSSETUP_FAIL;
        }
        debug("tsigkey");
        result = dns_tsigkey_create(&keyname, dns_tsig_hmacmd5_name,
                        secretstore, secretsize,
                        ISC_TRUE, NULL, now, now, mctx,
                        keyring, &key);
        if (result != ISC_R_SUCCESS) {
            printf (";; Couldn't create key %s: %s\n",
                keynametext, dns_result_totext(result));
        }
        isc_mem_put(mctx, secretstore, secretsize);
        dns_name_invalidate(&keyname);
        isc_buffer_free(&namebuf);
        return;
    SYSSETUP_FAIL:
        isc_mem_put(mctx, secretstore, secretsize);
        dns_name_invalidate(&keyname);
        isc_buffer_free(&namebuf);
        dns_tsigkeyring_destroy(&keyring);
        return;
    }
}

void
setup_libs(void) {
    isc_result_t result;

    debug ("setup_libs()");

    /*
     * Warning: This is not particularly good randomness.  We'll
     * just use random() now for getting id values, but doing so
     * does NOT insure that id's cann't be guessed.
     */
    srandom (getpid() + (int)&setup_libs);

    result = isc_app_start();
    check_result(result, "isc_app_start");

    result = isc_net_probeipv4();
    check_result(result, "isc_net_probeipv4");

    result = isc_net_probeipv6();
    if (result == ISC_R_SUCCESS)
        have_ipv6=ISC_TRUE;

    result = isc_mem_create(0, 0, &mctx);
    check_result(result, "isc_mem_create");

    result = isc_taskmgr_create (mctx, 1, 0, &taskmgr);
    check_result(result, "isc_taskmgr_create");

    result = isc_task_create (taskmgr, 0, &global_task);
    check_result(result, "isc_task_create");

    result = isc_timermgr_create (mctx, &timermgr);
    check_result(result, "isc_timermgr_create");

    result = isc_socketmgr_create (mctx, &socketmgr);
    check_result(result, "isc_socketmgr_create");

    result = isc_entropy_create (mctx, &entp);
    check_result(result, "isc_entropy_create");

    result = dst_lib_init (mctx, entp, 0);
    check_result(result, "dst_lib_init");
    is_dst_up = ISC_TRUE;
}

static void
add_opt (dns_message_t *msg, isc_uint16_t udpsize) {
    dns_rdataset_t *rdataset = NULL;
    dns_rdatalist_t *rdatalist = NULL;
    dns_rdata_t *rdata = NULL;
    isc_result_t result;

    debug ("add_opt()");
    result = dns_message_gettemprdataset(msg, &rdataset);
    check_result (result, "dns_message_gettemprdataset");
    dns_rdataset_init (rdataset);
    result = dns_message_gettemprdatalist(msg, &rdatalist);
    check_result (result, "dns_message_gettemprdatalist");
    result = dns_message_gettemprdata(msg, &rdata);
    check_result (result, "dns_message_gettemprdata");

    debug ("Setting udp size of %d", udpsize);
    rdatalist->type = dns_rdatatype_opt;
    rdatalist->covers = 0;
    rdatalist->rdclass = udpsize;
    rdatalist->ttl = 0;
    rdata->data = NULL;
    rdata->length = 0;
    ISC_LIST_INIT(rdatalist->rdata);
    ISC_LIST_APPEND(rdatalist->rdata, rdata, link);
    dns_rdatalist_tordataset(rdatalist, rdataset);
    result = dns_message_setopt(msg, rdataset);
    check_result (result, "dns_message_setopt");
}

static void
add_type(dns_message_t *message, dns_name_t *name, dns_rdataclass_t rdclass,
     dns_rdatatype_t rdtype)
{
    dns_rdataset_t *rdataset;
    isc_result_t result;

    debug ("add_type()");
    rdataset = NULL;
    result = dns_message_gettemprdataset(message, &rdataset);
    check_result(result, "dns_message_gettemprdataset()");
    dns_rdataset_init(rdataset);
    dns_rdataset_makequestion(rdataset, rdclass, rdtype);
    ISC_LIST_APPEND(name->list, rdataset, link);
}

static void
check_next_lookup(dig_lookup_t *lookup) {
    dig_lookup_t *next;
    dig_query_t *query;
    isc_boolean_t still_working=ISC_FALSE;

    if (free_now)
        return;

    debug("check_next_lookup(%p)", lookup);
    for (query = ISC_LIST_HEAD(lookup->q);
         query != NULL;
         query = ISC_LIST_NEXT(query, link)) {
        if (query->working) {
            debug("Still have a worker.", stderr);
            still_working=ISC_TRUE;
        }
    }
    if (still_working)
        return;

    debug ("Have %d retries left for %s",
           lookup->retries-1, lookup->textname);
    debug ("Lookup %s pending", lookup->pending?"is":"is not");

    next = ISC_LIST_NEXT(lookup, link);

    if (lookup->tcp_mode) {
        if (next == NULL) {
            debug("Shutting Down.", stderr);
            dighost_shutdown();
            return;
        }
        if (next->sendmsg == NULL) {
            debug ("Setting up for TCP");
            setup_lookup(next);
            do_lookup(next);
        }
    } else {
        if (!lookup->pending) {
            if (next == NULL) {
                debug("Shutting Down.", stderr);
                dighost_shutdown();
                return;
            }
            if (next->sendmsg == NULL) {
                debug ("Setting up for UDP");
                setup_lookup(next);
                do_lookup(next);
            }
        } else {
            if (lookup->retries > 1) {
                debug ("Retrying");
                lookup->retries --;
                if (lookup->timer != NULL)
                    isc_timer_detach(&lookup->timer);
                send_udp(lookup);
            } else {
                debug ("Cancelling");
                cancel_lookup(lookup);
            }
        }
    }
}


static void
followup_lookup(dns_message_t *msg, dig_query_t *query,
        dns_section_t section) {
    dig_lookup_t *lookup = NULL;
    dig_server_t *srv = NULL;
    dns_rdataset_t *rdataset = NULL;
    dns_rdata_t rdata;
    dns_name_t *name = NULL;
    isc_result_t result, loopresult;
    isc_buffer_t *b = NULL;
    isc_region_t r;
    isc_boolean_t success = ISC_FALSE;
    int len;

    debug ("followup_lookup()");
    if (free_now)
        return;
    result = dns_message_firstname (msg,section);
    if (result != ISC_R_SUCCESS) {
        debug ("Firstname returned %s",
            isc_result_totext(result));
        if ((section == DNS_SECTION_ANSWER) &&
            (query->lookup->trace || query->lookup->ns_search_only))
            followup_lookup (msg, query, DNS_SECTION_AUTHORITY);
                return;
    }

    debug ("Following up %s", query->lookup->textname);

    for (;;) {
        name = NULL;
        dns_message_currentname(msg, section, &name);
        for (rdataset = ISC_LIST_HEAD(name->list);
             rdataset != NULL;
             rdataset = ISC_LIST_NEXT(rdataset, link)) {
            loopresult = dns_rdataset_first(rdataset);
            while (loopresult == ISC_R_SUCCESS) {
                dns_rdataset_current(rdataset, &rdata);
                debug ("Got rdata with type %d",
                       rdata.type);
                if ((rdata.type == dns_rdatatype_ns) &&
                    (!query->lookup->trace_root ||
                     (query->lookup->nsfound < ROOTNS)))
                {
                    query->lookup->nsfound++;
                    result = isc_buffer_allocate(mctx, &b,
                                     BUFSIZE);
                    check_result (result,
                              "isc_buffer_allocate");
                    result = dns_rdata_totext (&rdata,
                                   NULL,
                                   b);
                    check_result (result,
                              "dns_rdata_totext");
                    isc_buffer_usedregion(b, &r);
                    len = r.length-1;
                    if (len >= MXNAME)
                        len = MXNAME-1;
                /* Initialize lookup if we've not yet */
                    debug ("Found NS %d %.*s",
                         (int)r.length, (int)r.length,
                         (char *)r.base);
                    if (!success) {
                        success = ISC_TRUE;
                        lookup_counter++;
                        lookup = requeue_lookup
                            (query->lookup,
                             ISC_FALSE);
                        lookup->doing_xfr = ISC_FALSE;
                        lookup->defname = ISC_FALSE;
                        lookup->use_my_server_list =
                            ISC_TRUE;
                        if (section ==
                            DNS_SECTION_ANSWER) {
                              lookup->trace =
                                ISC_FALSE;
                              lookup->ns_search_only =
                                ISC_FALSE;
                        }
                        else {
                              lookup->trace =
                                query->
                                lookup->trace;
                              lookup->ns_search_only =
                            query->
                            lookup->ns_search_only;
                        }
                        lookup->trace_root = ISC_FALSE;
                        ISC_LIST_INIT(lookup->
                                  my_server_list);
                    }
                    srv = isc_mem_allocate (mctx,
                                sizeof(
                                struct
                                dig_server));
                    if (srv == NULL)
                        fatal("Memory allocation "
                              "failure in %s:%d",
                              __FILE__, __LINE__);
                    strncpy(srv->servername,
                        (char *)r.base, len);
                    srv->servername[len]=0;
                    debug ("Adding server %s",
                           srv->servername);
                    ISC_LIST_APPEND
                        (lookup->my_server_list,
                         srv, link);
                    isc_buffer_free (&b);
                }
                loopresult = dns_rdataset_next(rdataset);
            }
        }
        result = dns_message_nextname (msg, section);
        if (result != ISC_R_SUCCESS)
            break;
    }
    if ((lookup == NULL) && (section == DNS_SECTION_ANSWER) &&
        (query->lookup->trace || query->lookup->ns_search_only))
        followup_lookup(msg, query, DNS_SECTION_AUTHORITY);
}

static void
next_origin(dns_message_t *msg, dig_query_t *query) {
    dig_lookup_t *lookup;

    UNUSED (msg);

    debug ("next_origin()");
    if (free_now)
        return;
    debug ("Following up %s", query->lookup->textname);

    if (query->lookup->origin == NULL) { /*Then we just did rootorg;
                          there's nothing left. */
        debug ("Made it to the root whith nowhere to go.");
        return;
    }
    lookup = requeue_lookup(query->lookup, ISC_TRUE);
    lookup->defname = ISC_FALSE;
    lookup->origin = ISC_LIST_NEXT(query->lookup->origin, link);
}


static void
insert_soa(dig_lookup_t *lookup) {
    isc_result_t result;
    dns_rdata_soa_t soa;
    dns_rdata_t *rdata = NULL;
    dns_rdatalist_t *rdatalist = NULL;
    dns_rdataset_t *rdataset = NULL;
    dns_name_t *soaname = NULL;

    debug ("insert_soa()");
    soa.mctx = mctx;
    soa.serial = lookup->ixfr_serial;
    soa.refresh = 1;
    soa.retry = 1;
    soa.expire = 1;
    soa.minimum = 1;
    soa.common.rdclass = dns_rdataclass_in;
    soa.common.rdtype = dns_rdatatype_soa;

    dns_name_init(&soa.origin, NULL);
    dns_name_init(&soa.mname, NULL);

    dns_name_clone(lookup->name, &soa.origin);
    dns_name_clone(lookup->name, &soa.mname);

    isc_buffer_init(&lookup->rdatabuf, lookup->rdatastore,
            MXNAME);

    result = dns_message_gettemprdata(lookup->sendmsg, &rdata);
    check_result(result, "dns_message_gettemprdata");
    result = dns_rdata_fromstruct(rdata, dns_rdataclass_in,
                      dns_rdatatype_soa, &soa,
                      &lookup->rdatabuf);
    check_result(result, "isc_rdata_fromstruct");

    result = dns_message_gettemprdatalist(lookup->sendmsg, &rdatalist);
    check_result(result, "dns_message_gettemprdatalist");

    result = dns_message_gettemprdataset(lookup->sendmsg, &rdataset);
    check_result(result, "dns_message_gettemprdataset");

    dns_rdatalist_init(rdatalist);
    rdatalist->type = dns_rdatatype_soa;
    rdatalist->rdclass = dns_rdataclass_in;
    rdatalist->covers = dns_rdatatype_soa;
    rdatalist->ttl = 1;
    ISC_LIST_INIT(rdatalist->rdata);
    ISC_LIST_APPEND(rdatalist->rdata, rdata, link);

    dns_rdataset_init(rdataset);
    dns_rdatalist_tordataset(rdatalist, rdataset);

    result = dns_message_gettempname(lookup->sendmsg, &soaname);
    check_result(result, "dns_message_gettempname");
    dns_name_init(soaname, NULL);
    dns_name_clone(lookup->name, soaname);
    ISC_LIST_INIT(soaname->list);
    ISC_LIST_APPEND(soaname->list, rdataset, link);
    dns_message_addname(lookup->sendmsg, soaname, DNS_SECTION_AUTHORITY);
}

void
setup_lookup(dig_lookup_t *lookup) {
    isc_result_t result, res2;
    int len;
    dns_rdatatype_t rdtype;
    dns_rdataclass_t rdclass;
    dig_server_t *serv;
    dig_query_t *query;
    isc_region_t r;
    isc_constregion_t tr;
    isc_buffer_t b;
    char store[MXNAME];

    REQUIRE (lookup != NULL);

    debug("setup_lookup(%p)",lookup);

    if (free_now)
        return;

    debug("Setting up for looking up %s @%p->%p",
        lookup->textname, lookup,
        lookup->link.next);

    result = dns_message_create(mctx, DNS_MESSAGE_INTENTRENDER,
                    &lookup->sendmsg);
    check_result(result, "dns_message_create");

    if (lookup->new_search) {
        debug ("Resetting lookup counter.");
        lookup_counter = 0;
    }

    result = dns_message_gettempname(lookup->sendmsg, &lookup->name);
    check_result(result, "dns_message_gettempname");
    dns_name_init(lookup->name, NULL);

    isc_buffer_init(&lookup->namebuf, lookup->namespace, BUFSIZE);
    isc_buffer_init(&lookup->onamebuf, lookup->onamespace, BUFSIZE);

    if ((count_dots(lookup->textname) >= ndots) || lookup->defname)
        lookup->origin = NULL; /* Force root lookup */
    debug ("lookup->origin = %p", lookup->origin);
    if (lookup->origin != NULL) {
        debug ("Trying origin %s", lookup->origin->origin);
        result = dns_message_gettempname(lookup->sendmsg,
                         &lookup->oname);
        check_result(result, "dns_message_gettempname");
        dns_name_init(lookup->oname, NULL);
        len=strlen(lookup->origin->origin);
        isc_buffer_init(&b, lookup->origin->origin, len);
        isc_buffer_add(&b, len);
        result = dns_name_fromtext(lookup->oname, &b, dns_rootname,
                       ISC_FALSE, &lookup->onamebuf);
        if (result != ISC_R_SUCCESS) {
        dns_message_puttempname(lookup->sendmsg,
                        &lookup->name);
            dns_message_puttempname(lookup->sendmsg,
                        &lookup->oname);
            fatal("Aborting: %s is not a legal name syntax. (%s)",
                  lookup->origin->origin,
                  dns_result_totext(result));
        }
        if (!lookup->trace_root) {
            len=strlen(lookup->textname);
            isc_buffer_init(&b, lookup->textname, len);
            isc_buffer_add(&b, len);
            result = dns_name_fromtext(lookup->name, &b,
                           lookup->oname, ISC_FALSE,
                           &lookup->namebuf);
        } else {
            isc_buffer_init(&b, ". ", 1);
            isc_buffer_add(&b, 1);
            result = dns_name_fromtext(lookup->name, &b,
                           lookup->oname, ISC_FALSE,
                           &lookup->namebuf);
        }
        if (result != ISC_R_SUCCESS) {
            dns_message_puttempname(lookup->sendmsg,
                        &lookup->name);
            dns_message_puttempname(lookup->sendmsg,
                        &lookup->oname);
            fatal("Aborting: %s is not a legal name syntax. (%s)",
                  lookup->textname, dns_result_totext(result));
        }
        dns_message_puttempname(lookup->sendmsg, &lookup->oname);
    } else {
        debug ("Using root origin.");
        if (!lookup->trace_root) {
            len = strlen (lookup->textname);
            isc_buffer_init(&b, lookup->textname, len);
            isc_buffer_add(&b, len);
            result = dns_name_fromtext(lookup->name, &b,
                           dns_rootname,
                           ISC_FALSE,
                           &lookup->namebuf);
        } else {
            isc_buffer_init(&b, ". ", 1);
            isc_buffer_add(&b, 1);
            result = dns_name_fromtext(lookup->name, &b,
                           dns_rootname,
                           ISC_FALSE,
                           &lookup->namebuf);
        }
        if (result != ISC_R_SUCCESS) {
            dns_message_puttempname(lookup->sendmsg,
                        &lookup->name);
            isc_buffer_init(&b, store, MXNAME);
            res2 = dns_name_totext(dns_rootname, ISC_FALSE, &b);
            check_result (res2, "dns_name_totext");
            isc_buffer_usedregion (&b, &r);
            fatal("Aborting: %s/%.*s is not a legal name syntax. "
                  "(%s)", lookup->textname, (int)r.length,
                  (char *)r.base, dns_result_totext(result));
        }
    }
    isc_buffer_init (&b, store, MXNAME);
    dns_name_totext(lookup->name, ISC_FALSE, &b);
    isc_buffer_usedregion (&b, &r);
    trying((int)r.length, (char *)r.base, lookup);
    if (dns_name_isabsolute(lookup->name))
        debug ("This is an absolute name.");
    else
        debug ("This is a relative name (which is wrong).");

    if (lookup->rctext[0] == 0)
        strcpy(lookup->rctext, "IN");
    if (lookup->rttext[0] == 0)
        strcpy(lookup->rttext, "A");

    lookup->sendmsg->id = (unsigned short)(random() & 0xFFFF);
    lookup->sendmsg->opcode = dns_opcode_query;
    lookup->msgcounter = 0;
    /*
     * If this is a trace request, completely disallow recursion, since
     * it's meaningless for traces.
     */
    if (lookup->recurse && !lookup->trace && !lookup->ns_search_only) {
        debug ("Recursive query");
        lookup->sendmsg->flags |= DNS_MESSAGEFLAG_RD;
    }

    if (lookup->aaonly) {
        debug ("AA query");
        lookup->sendmsg->flags |= DNS_MESSAGEFLAG_AA;
    }

    if (lookup->adflag) {
        debug ("AD query");
        lookup->sendmsg->flags |= DNS_MESSAGEFLAG_AD;
    }

    if (lookup->cdflag) {
        debug ("CD query");
        lookup->sendmsg->flags |= DNS_MESSAGEFLAG_CD;
    }

    dns_message_addname(lookup->sendmsg, lookup->name,
                DNS_SECTION_QUESTION);

    if (lookup->trace_root) {
        debug("Doing trace_root");
        tr.base="SOA";
        tr.length=3;
    } else {
        tr.base=lookup->rttext;
        tr.length=strlen(lookup->rttext);
    }
    debug ("Data type is %s", lookup->rttext);
    result = dns_rdatatype_fromtext(&rdtype, (isc_textregion_t *)&tr);
    check_result(result, "dns_rdatatype_fromtext");
    if ((rdtype == dns_rdatatype_axfr) ||
        (rdtype == dns_rdatatype_ixfr)) {
        lookup->doing_xfr = ISC_TRUE;
        /*
         * Force TCP mode if we're doing an xfr.
         */
        lookup->tcp_mode = ISC_TRUE;
    }
    if (lookup->trace_root) {
        tr.base="IN";
        tr.length=2;
    } else {
        tr.base=lookup->rctext;
        tr.length=strlen(lookup->rctext);
    }
    result = dns_rdataclass_fromtext(&rdclass, (isc_textregion_t *)&tr);
    check_result(result, "dns_rdataclass_fromtext");
    add_type(lookup->sendmsg, lookup->name, rdclass, rdtype);

    if (rdtype == dns_rdatatype_ixfr)
        insert_soa(lookup);

    if (key != NULL) {
        debug ("Initializing keys");
        result = dns_message_settsigkey(lookup->sendmsg, key);
        check_result(result, "dns_message_settsigkey");
        lookup->tsigctx = NULL;
        lookup->querysig = NULL;
    }

    debug ("Starting to render the message");
    isc_buffer_init(&lookup->sendbuf, lookup->sendspace, COMMSIZE);
    result = dns_message_renderbegin(lookup->sendmsg, &lookup->sendbuf);
    check_result(result, "dns_message_renderbegin");
    if (lookup->udpsize > 0) {
        add_opt(lookup->sendmsg, lookup->udpsize);
    }
    result = dns_message_rendersection(lookup->sendmsg,
                       DNS_SECTION_QUESTION, 0);
    check_result(result, "dns_message_rendersection");
    result = dns_message_rendersection(lookup->sendmsg,
                       DNS_SECTION_AUTHORITY, 0);
    check_result(result, "dns_message_rendersection");
    result = dns_message_renderend(lookup->sendmsg);
    check_result(result, "dns_message_renderend");
    debug ("Done rendering.");

    lookup->pending = ISC_FALSE;

    if (lookup->use_my_server_list)
        serv = ISC_LIST_HEAD(lookup->my_server_list);
    else
        serv = ISC_LIST_HEAD(server_list);
    for (; serv != NULL;
         serv = ISC_LIST_NEXT(serv, link)) {
        query = isc_mem_allocate(mctx, sizeof(dig_query_t));
        if (query == NULL)
            fatal("Memory allocation failure in %s:%d",
                  __FILE__, __LINE__);
        debug ("Create query %p linked to lookup %p",
               query, lookup);
        query->lookup = lookup;
        query->working = ISC_FALSE;
        query->waiting_connect = ISC_FALSE;
        query->first_pass = ISC_TRUE;
        query->first_soa_rcvd = ISC_FALSE;
        query->second_rr_rcvd = ISC_FALSE;
        query->second_rr_serial = 0;
        query->servname = serv->servername;
        ISC_LIST_INIT(query->sendlist);
        ISC_LIST_INIT(query->recvlist);
        ISC_LIST_INIT(query->lengthlist);
        query->sock = NULL;

        isc_buffer_init(&query->recvbuf, query->recvspace, COMMSIZE);
        isc_buffer_init(&query->lengthbuf, query->lengthspace, 2);
        isc_buffer_init(&query->slbuf, query->slspace, 2);

        ISC_LIST_ENQUEUE(lookup->q, query, link);
    }
    if (!ISC_LIST_EMPTY(lookup->q) && qr) {
        printmessage (ISC_LIST_HEAD(lookup->q), lookup->sendmsg,
                  ISC_TRUE);
    }
}

static void
send_done(isc_task_t *task, isc_event_t *event) {
    UNUSED(task);

    isc_event_free(&event);

    debug("send_done()");
}

static void
cancel_lookup(dig_lookup_t *lookup) {
    dig_query_t *query=NULL;

    debug("cancel_lookup()");
    for (query = ISC_LIST_HEAD(lookup->q);
         query != NULL;
         query = ISC_LIST_NEXT(query, link)) {
        if (query->working) {
            debug ("Cancelling a worker.");
        }
        if (query->sock != NULL) {
            isc_socket_cancel(query->sock, global_task,
                      ISC_SOCKCANCEL_ALL);
            isc_socket_detach(&query->sock);
            sockcount--;
            debug ("Socket = %d",sockcount);
        }
    }
    lookup->pending = ISC_FALSE;
    lookup->retries = 0;
    check_next_lookup(lookup);
}

static void
recv_done(isc_task_t *task, isc_event_t *event);

static void
connect_timeout(isc_task_t *task, isc_event_t *event);

void
send_udp(dig_lookup_t *lookup) {
    dig_query_t *query;
    isc_result_t result;

    debug ("send_udp()");

    isc_interval_set(&lookup->interval, timeout, 0);
    result = isc_timer_create(timermgr, isc_timertype_once, NULL,
                  &lookup->interval, global_task,
                  connect_timeout, lookup, &lookup->timer);
    check_result(result, "isc_timer_create");
    for (query = ISC_LIST_HEAD(lookup->q);
         query != NULL;
         query = ISC_LIST_NEXT(query, link)) {
        debug ("Working on lookup %p, query %p",
               query->lookup, query);
        ISC_LIST_ENQUEUE(query->recvlist, &query->recvbuf, link);
        query->working = ISC_TRUE;
        debug ("recving with lookup=%p, query=%p, sock=%p",
               query->lookup, query,
               query->sock);
        result = isc_socket_recvv(query->sock, &query->recvlist, 1,
                      global_task, recv_done, query);
        check_result(result, "isc_socket_recvv");
        sendcount++;
        debug("Sent count number %d", sendcount);
        ISC_LIST_ENQUEUE(query->sendlist, &lookup->sendbuf, link);
        debug("Sending a request.");
        result = isc_time_now(&query->time_sent);
        check_result(result, "isc_time_now");
        ENSURE (query->sock != NULL);
        result = isc_socket_sendtov(query->sock, &query->sendlist,
                        global_task, send_done, query,
                        &query->sockaddr, NULL);
        check_result(result, "isc_socket_sendtov");
    }
}

/* connect_timeout is used for both UDP recieves and TCP connects. */
static void
connect_timeout(isc_task_t *task, isc_event_t *event) {
    dig_lookup_t *lookup=NULL;
    dig_query_t *q=NULL;
    isc_result_t result;
    isc_buffer_t *b=NULL;
    isc_region_t r;

    REQUIRE(event->ev_type == ISC_TIMEREVENT_IDLE);

    debug("connect_timeout()");
    lookup = event->ev_arg;

    isc_event_free(&event);

    debug ("Buffer Allocate connect_timeout");
    result = isc_buffer_allocate(mctx, &b, 256);
    check_result(result, "isc_buffer_allocate");
    for (q = ISC_LIST_HEAD(lookup->q);
         q != NULL;
         q = ISC_LIST_NEXT(q, link)) {
        if (q->working) {
            if (!free_now) {
                isc_buffer_clear(b);
                result = isc_sockaddr_totext(&q->sockaddr, b);
                check_result(result, "isc_sockaddr_totext");
                isc_buffer_usedregion(b, &r);
                if (q->lookup->retries > 1)
                    printf(";; Connection to server %.*s "
                           "for %s timed out.  "
                           "Retrying %d.\n",
                           (int)r.length, r.base,
                           q->lookup->textname,
                           q->lookup->retries-1);
                else {
                    printf(";; Connection to "
                           "server %.*s "
                           "for %s timed out.  "
                           "Giving up.\n",
                           (int)r.length, r.base,
                           q->lookup->textname);
                }
            }
            isc_socket_cancel(q->sock, task,
                      ISC_SOCKCANCEL_ALL);
        }
    }
    ENSURE(lookup->timer != NULL);
    isc_timer_detach(&lookup->timer);
    isc_buffer_free(&b);
    debug ("Done with connect_timeout()");
}

static void
tcp_length_done(isc_task_t *task, isc_event_t *event) {
    isc_socketevent_t *sevent;
    isc_buffer_t *b=NULL;
    isc_region_t r;
    isc_result_t result;
    dig_query_t *query=NULL;
    isc_uint16_t length;

    REQUIRE(event->ev_type == ISC_SOCKEVENT_RECVDONE);

    UNUSED(task);

    debug("tcp_length_done()");

    if (free_now) {
        isc_event_free(&event);
        return;
    }

    sevent = (isc_socketevent_t *)event;

    query = event->ev_arg;

    if (sevent->result == ISC_R_CANCELED) {
        query->working = ISC_FALSE;
        check_next_lookup(query->lookup);
        isc_event_free(&event);
        return;
    }
    if (sevent->result != ISC_R_SUCCESS) {
        debug ("Buffer Allocate connect_timeout");
        result = isc_buffer_allocate(mctx, &b, 256);
        check_result(result, "isc_buffer_allocate");
        result = isc_sockaddr_totext(&query->sockaddr, b);
        check_result(result, "isc_sockaddr_totext");
        isc_buffer_usedregion(b, &r);
        printf("%.*s: %s\n", (int)r.length, r.base,
               isc_result_totext(sevent->result));
        isc_buffer_free(&b);
        query->working = ISC_FALSE;
        sockcount--;
        debug ("Socket = %d",sockcount);
        isc_socket_detach(&query->sock);
        check_next_lookup(query->lookup);
        isc_event_free(&event);
        return;
    }
    b = ISC_LIST_HEAD(sevent->bufferlist);
    ISC_LIST_DEQUEUE(sevent->bufferlist, &query->lengthbuf, link);
    length = isc_buffer_getuint16(b);
    if (length > COMMSIZE) {
        isc_event_free (&event);
        fatal ("Length of %X was longer than I can handle!",
               length);
    }
    /*
     * Even though the buffer was already init'ed, we need
     * to redo it now, to force the length we want.
     */
    isc_buffer_invalidate(&query->recvbuf);
    isc_buffer_init(&query->recvbuf, query->recvspace, length);
    ENSURE(ISC_LIST_EMPTY(query->recvlist));
    ISC_LIST_ENQUEUE(query->recvlist, &query->recvbuf, link);
    debug ("recving with lookup=%p, query=%p",
           query->lookup, query);
    result = isc_socket_recvv(query->sock, &query->recvlist, length, task,
                  recv_done, query);
    check_result(result, "isc_socket_recvv");
    debug("Resubmitted recv request with length %d", length);
    isc_event_free(&event);
}

static void
launch_next_query(dig_query_t *query, isc_boolean_t include_question) {
    isc_result_t result;

    debug("launch_next_query()");

    if (free_now)
        return;

    if (!query->lookup->pending) {
        debug("Ignoring launch_next_query because !pending.");
        sockcount--;
        debug ("Socket = %d",sockcount);
        isc_socket_detach(&query->sock);
        query->working = ISC_FALSE;
        query->waiting_connect = ISC_FALSE;
        check_next_lookup(query->lookup);
        return;
    }

    isc_buffer_clear(&query->slbuf);
    isc_buffer_clear(&query->lengthbuf);
    isc_buffer_putuint16(&query->slbuf, query->lookup->sendbuf.used);
    ISC_LIST_ENQUEUE(query->sendlist, &query->slbuf, link);
    if (include_question) {
        ISC_LIST_ENQUEUE(query->sendlist, &query->lookup->sendbuf,
                 link);
    }
    ISC_LIST_ENQUEUE(query->lengthlist, &query->lengthbuf, link);

    result = isc_socket_recvv(query->sock, &query->lengthlist, 0,
                  global_task, tcp_length_done, query);
    check_result(result, "isc_socket_recvv");
    sendcount++;
    if (!query->first_soa_rcvd) {
        debug("Sending a request.");
        result = isc_time_now(&query->time_sent);
        check_result(result, "isc_time_now");
        result = isc_socket_sendv(query->sock, &query->sendlist,
                      global_task, send_done, query);
        check_result(result, "isc_socket_recvv");
    }
    query->waiting_connect = ISC_FALSE;
    check_next_lookup(query->lookup);
    return;
}

static void
connect_done(isc_task_t *task, isc_event_t *event) {
    isc_result_t result;
    isc_socketevent_t *sevent=NULL;
    dig_query_t *query=NULL;
    isc_buffer_t *b=NULL;
    isc_region_t r;

    UNUSED(task);

    REQUIRE(event->ev_type == ISC_SOCKEVENT_CONNECT);

    debug ("connect_done()");

    if (free_now) {
        isc_event_free(&event);
        return;
    }

    sevent = (isc_socketevent_t *)event;
    query = sevent->ev_arg;

    REQUIRE(query->waiting_connect);

    query->waiting_connect = ISC_FALSE;

    if (sevent->result != ISC_R_SUCCESS) {
        debug ("Buffer Allocate connect_timeout");
        result = isc_buffer_allocate(mctx, &b, 256);
        check_result(result, "isc_buffer_allocate");
        result = isc_sockaddr_totext(&query->sockaddr, b);
        check_result(result, "isc_sockaddr_totext");
        isc_buffer_usedregion(b, &r);
        printf(";; Connection to server %.*s for %s failed: %s.\n",
               (int)r.length, r.base, query->lookup->textname,
               isc_result_totext(sevent->result));
        if (exitcode < 9)
            exitcode = 9;
        isc_buffer_free(&b);
        query->working = ISC_FALSE;
        query->waiting_connect = ISC_FALSE;
        check_next_lookup(query->lookup);
        isc_event_free(&event);
        return;
    }
    launch_next_query(query, ISC_TRUE);
    isc_event_free(&event);
}


#if 0
static isc_boolean_t
msg_contains_soa(dns_message_t *msg, dig_query_t *query) {
    isc_result_t result;
    dns_name_t *name=NULL;

    debug("msg_contains_soa()");

    result = dns_message_findname(msg, DNS_SECTION_ANSWER,
                      query->lookup->name, dns_rdatatype_soa,
                      0, &name, NULL);
    if (result == ISC_R_SUCCESS) {
        debug("Found SOA", stderr);
        return (ISC_TRUE);
    } else {
        debug("Didn't find SOA, result=%d:%s",
              result, dns_result_totext(result));
        return (ISC_FALSE);
    }

}
#endif

static void
check_for_more_data(dig_query_t *query, dns_message_t *msg,
            isc_socketevent_t *sevent)
{
    dns_rdataset_t *rdataset = NULL;
    dns_rdata_t rdata;
    dns_rdata_soa_t soa;
    isc_result_t result;
    isc_buffer_t b;
    isc_region_t r;
    char *abspace[MXNAME];

    debug ("check_for_more_data()");

    /*
     * By the time we're in this routine, we know we're doing
     * either an AXFR or IXFR.  If there's no second_rr_type,
     * then we don't yet know which kind of answer we got back
     * from the server.  Here, we're going to walk through the
     * rr's in the message, acting as necessary whenever we hit
     * an SOA rr.
     */

    result = dns_message_firstname(msg, DNS_SECTION_ANSWER);
    if (result != ISC_R_SUCCESS) {
        puts("; Transfer failed.");
        query->working = ISC_FALSE;
        cancel_lookup(query->lookup);
        return;
    }
#ifdef NEVER
    check_result(result, "dns_message_firstname");
#endif
    do {
        dns_name_t *name = NULL;
        dns_message_currentname(msg, DNS_SECTION_ANSWER,
                    &name);
        for (rdataset = ISC_LIST_HEAD(name->list);
             rdataset != NULL;
             rdataset = ISC_LIST_NEXT(rdataset, link)) {
            result = dns_rdataset_first(rdataset);
            if (result != ISC_R_SUCCESS)
                continue;
            do {
                dns_rdataset_current(rdataset, &rdata);
                /*
                 * If this is the first rr, make sure
                 * it's an SOA
                 */
                if ((!query->first_soa_rcvd) &&
                    (rdata.type != dns_rdatatype_soa)) {
                    puts("; Transfer failed.  "
                         "Didn't start with "
                         "SOA answer.");
                    query->working = ISC_FALSE;
                    cancel_lookup(query->lookup);
                    return;
                }
                if ((!query->second_rr_rcvd) &&
                    (rdata.type != dns_rdatatype_soa)) {
                    query->second_rr_rcvd = ISC_TRUE;
                    query->second_rr_serial = 0;
                    debug ("Got the second rr as nonsoa");
                    continue;
                }

                /*
                 * If the record is anything except an SOA
                 * now, just continue on...
                 */
                if (rdata.type != dns_rdatatype_soa)
                    goto NEXT_RDATA;
                /* Now we have an SOA.  Work with it. */
                debug ("Got an SOA");
                result = dns_rdata_tostruct(&rdata,
                                &soa,
                                mctx);
                check_result(result,
                         "dns_rdata_tostruct");
                if (!query->first_soa_rcvd) {
                    query->first_soa_rcvd =
                        ISC_TRUE;
                    query->first_rr_serial =
                        soa.serial;
                    debug ("This is the first. %d",
                           query->lookup->ixfr_serial);
                    if (query->lookup->ixfr_serial >=
                        soa.serial) {
                        dns_rdata_freestruct(&soa);
                        goto XFR_DONE;
                    }
                    dns_rdata_freestruct(&soa);
                    goto NEXT_RDATA;
                }
                if (!query->second_rr_rcvd) {
                    debug ("This is the second. %d",
                           query->lookup->ixfr_serial);
                    query->second_rr_rcvd = ISC_TRUE;
                    query->second_rr_serial =
                        soa.serial;
                    dns_rdata_freestruct(&soa);
                    goto NEXT_RDATA;
                }
                if (query->second_rr_serial == 0) {
                    /*
                     * If the second RR was a non-SOA
                     * record, and we're getting any
                     * other SOA, then this is an
                     * AXFR, and we're done.
                     */
                    debug ("Done, since axfr.");
                XFR_DONE:
                    isc_buffer_init(&b, abspace, MXNAME);
                    result = isc_sockaddr_totext(&sevent->
                                     address,
                                     &b);
                    check_result(result,
                             "isc_sockaddr_totext");
                    isc_buffer_usedregion(&b, &r);
                    received(b.used, r.length,
                         (char *)r.base, query);
                    query->working = ISC_FALSE;
                    cancel_lookup(query->lookup);
                    dns_rdata_freestruct(&soa);
                    return;
                }
                /*
                 * If we get to this point, we're doing an
                 * IXFR and have to start really looking
                 * at serial numbers.
                 */
                if (query->first_rr_serial == soa.serial) {
                    debug ("Got a match for ixfr");
                    if (!query->first_repeat_rcvd) {
                        query->first_repeat_rcvd =
                            ISC_TRUE;
                        dns_rdata_freestruct(&soa);
                        goto NEXT_RDATA;
                    }
                    debug ("Done with ixfr");
                    dns_rdata_freestruct(&soa);
                    goto XFR_DONE;
                }
                debug ("Meaningless soa, %d",
                       soa.serial);
                dns_rdata_freestruct(&soa);
            NEXT_RDATA:
                result = dns_rdataset_next(rdataset);
            } while (result == ISC_R_SUCCESS);
        }
        result = dns_message_nextname(msg, DNS_SECTION_ANSWER);
    } while (result == ISC_R_SUCCESS);
    launch_next_query(query, ISC_FALSE);
    return;
}

static void
recv_done(isc_task_t *task, isc_event_t *event) {
    isc_socketevent_t *sevent = NULL;
    dig_query_t *query = NULL;
    isc_buffer_t *b = NULL;
    dns_message_t *msg = NULL;
    isc_result_t result;
    isc_buffer_t ab;
    char abspace[MXNAME];
    isc_region_t r;
    dig_lookup_t *n;

    UNUSED (task);

    debug ("recv_done()");

    if (free_now) {
        isc_event_free(&event);
        return;
    }

    query = event->ev_arg;
    debug("(lookup=%p, query=%p)",
          query->lookup, query);

    if (free_now) {
        debug("Bailing out, since freeing now.");
        isc_event_free(&event);
        return;
    }

    sendcount--;
    debug("In recv_done, counter down to %d", sendcount);
    REQUIRE(event->ev_type == ISC_SOCKEVENT_RECVDONE);
    sevent = (isc_socketevent_t *)event;

    if (!query->lookup->pending && !query->lookup->ns_search_only) {

        debug("No longer pending.  Got %s",
            isc_result_totext(sevent->result));
        query->working = ISC_FALSE;
        query->waiting_connect = ISC_FALSE;

        cancel_lookup(query->lookup);
        isc_event_free(&event);
        return;
    }

    if (sevent->result == ISC_R_SUCCESS) {
        b = ISC_LIST_HEAD(sevent->bufferlist);
        ISC_LIST_DEQUEUE(sevent->bufferlist, &query->recvbuf, link);
        result = dns_message_create(mctx, DNS_MESSAGE_INTENTPARSE,
                        &msg);
        check_result(result, "dns_message_create");

        if (key != NULL) {
            debug ("querysig 1 is %p", query->lookup->querysig);
            if (query->lookup->querysig == NULL) {
                debug ("Getting initial querysig");
                result = dns_message_getquerytsig(
                         query->lookup->sendmsg,
                         mctx, &query->lookup->querysig);
                check_result(result,
                         "dns_message_getquerytsig");
            }
            result = dns_message_setquerytsig(msg,
                         query->lookup->querysig);
            check_result(result, "dns_message_setquerytsig");
            result = dns_message_settsigkey(msg, key);
            check_result(result, "dns_message_settsigkey");
            msg->tsigctx = query->lookup->tsigctx;
            if (query->lookup->msgcounter != 0)
                msg->tcp_continuation = 1;
            query->lookup->msgcounter++;
        }
        debug ("Before parse starts");
        result = dns_message_parse(msg, b, ISC_TRUE);
        if (result != ISC_R_SUCCESS) {
            printf (";; Got bad UDP packet:\n");
            hex_dump(b);
            query->working = ISC_FALSE;
            query->waiting_connect = ISC_FALSE;
            if (!query->lookup->tcp_mode) {
                printf (";; Retrying in TCP mode.\n");
                n = requeue_lookup(query->lookup, ISC_TRUE);
                n->tcp_mode = ISC_TRUE;
            }
            cancel_lookup(query->lookup);
            dns_message_destroy(&msg);
            isc_event_free(&event);
            return;
        }
        if (key != NULL) {
            debug ("querysig 2 is %p", query->lookup->querysig);
            debug ("Before verify");
            result = dns_tsig_verify(&query->recvbuf, msg,
                         NULL, keyring);
            debug ("After verify");
            if (result != ISC_R_SUCCESS) {
                printf (";; Couldn't verify signature: %s\n",
                    dns_result_totext(result));
                validated = ISC_FALSE;
            }
            query->lookup->tsigctx = msg->tsigctx;
            if (query->lookup->querysig != NULL) {
                debug ("Freeing querysig buffer %p",
                       query->lookup->querysig);
                isc_buffer_free(&query->lookup->querysig);
            }
            result = dns_message_getquerytsig(msg, mctx,
                             &query->lookup->querysig);
            check_result(result,"dns_message_getquerytsig");
            debug ("querysig 3 is %p", query->lookup->querysig);
        }
        debug ("After parse");
        if (query->lookup->xfr_q == NULL)
            query->lookup->xfr_q = query;
        if (query->lookup->xfr_q == query) {
            if ((query->lookup->trace)||
                (query->lookup->ns_search_only)) {
                debug ("In TRACE code");
                if ((show_details ||
                    ((dns_message_firstname(msg,
                                DNS_SECTION_ANSWER)
                      == ISC_R_SUCCESS))) &&
                    !query->lookup->trace_root ) {
                    printmessage(query, msg, ISC_TRUE);
                }
                if ((msg->rcode != 0) &&
                    (query->lookup->origin != NULL)) {
                    next_origin(msg, query);
                } else {
                    result = dns_message_firstname
                        (msg,DNS_SECTION_ANSWER);
                    if ((result != ISC_R_SUCCESS) ||
                        query->lookup->trace_root)
                        followup_lookup(msg, query,
                            DNS_SECTION_AUTHORITY);
                }
            } else if ((msg->rcode != 0) &&
                 (query->lookup->origin != NULL)) {
                next_origin(msg, query);
                if (show_details) {
                       printmessage(query, msg, ISC_TRUE);
                }
            } else {
                if (query->first_soa_rcvd &&
                    query->lookup->doing_xfr)
                    printmessage(query, msg, ISC_FALSE);
                else
                    printmessage(query, msg, ISC_TRUE);
            }
        } else if (( dns_message_firstname(msg, DNS_SECTION_ANSWER)
                == ISC_R_SUCCESS) &&
               query->lookup->ns_search_only &&
               !query->lookup->trace_root ) {
            printmessage (query, msg, ISC_TRUE);
        }

        if (query->lookup->pending)
            debug("Still pending.");
        if (query->lookup->doing_xfr) {
            if (query != query->lookup->xfr_q) {
                dns_message_destroy (&msg);
                isc_event_free (&event);
                query->working = ISC_FALSE;
                query->waiting_connect = ISC_FALSE;
                return;
            }
            check_for_more_data(query, msg, sevent);
        }
        else {
            if ((msg->rcode == 0) ||
                (query->lookup->origin == NULL)) {
                isc_buffer_init(&ab, abspace, MXNAME);
                result = isc_sockaddr_totext(&sevent->address,
                                 &ab);
                check_result(result, "isc_sockaddr_totext");
                isc_buffer_usedregion(&ab, &r);
                if ((( dns_message_firstname(msg,
                                DNS_SECTION_ANSWER)
                      == ISC_R_SUCCESS) &&
                    query->lookup->ns_search_only &&
                    !query->lookup->trace_root) ||
                     query->lookup->trace) {
                    received(b->used, r.length,
                         (char *)r.base,
                         query);
                }
            }
            query->working = ISC_FALSE;
            query->lookup->pending = ISC_FALSE;
            if (!query->lookup->ns_search_only ||
                query->lookup->trace_root ) {
                cancel_lookup(query->lookup);
            }
            check_next_lookup(query->lookup);
        }
        dns_message_destroy(&msg);
        isc_event_free(&event);
        return;
    }
    /* In truth, we should never get into the CANCELED routine, since
       the cancel_lookup() routine clears the pending flag. */
    if (sevent->result == ISC_R_CANCELED) {
        debug ("In cancel handler");
        query->working = ISC_FALSE;
        query->waiting_connect = ISC_FALSE;
        check_next_lookup(query->lookup);
        isc_event_free(&event);
        return;
    }
    fatal("recv_done got result %s",
          isc_result_totext(sevent->result));
}

void
get_address(char *host, in_port_t port, isc_sockaddr_t *sockaddr) {
    struct in_addr in4;
    struct in6_addr in6;
#if defined(HAVE_ADDRINFO) && defined(HAVE_GETADDRINFO)
    struct addrinfo *res = NULL;
    int result;
#else
    struct hostent *he;
#endif

    debug("get_address()");

    if (have_ipv6 && inet_pton(AF_INET6, host, &in6) == 1)
        isc_sockaddr_fromin6(sockaddr, &in6, port);
    else if (inet_pton(AF_INET, host, &in4) == 1)
        isc_sockaddr_fromin(sockaddr, &in4, port);
    else {
#if defined(HAVE_ADDRINFO) && defined(HAVE_GETADDRINFO)
        result = getaddrinfo(host, NULL, NULL, &res);
        if (result != 0) {
            fatal ("Couldn't find server %s.  %s",
                   host, gai_strerror(result));
        }
        memcpy(&sockaddr->type.sa,res->ai_addr, res->ai_addrlen);
        sockaddr->length = res->ai_addrlen;
        isc_sockaddr_setport(sockaddr, port);
        freeaddrinfo(res);
#else
        he = gethostbyname(host);
        if (he == NULL)
             fatal("Couldn't find server %s.  errno=%d",
                  host, h_errno);
        INSIST(he->h_addrtype == AF_INET);
        isc_sockaddr_fromin(sockaddr,
                    (struct in_addr *)(he->h_addr_list[0]),
                    port);
#endif
    }
}

static void
do_lookup_tcp(dig_lookup_t *lookup) {
    dig_query_t *query;
    isc_result_t result;

    debug("do_lookup_tcp()");
    lookup->pending = ISC_TRUE;
    isc_interval_set(&lookup->interval, timeout, 0);
    result = isc_timer_create(timermgr, isc_timertype_once, NULL,
                  &lookup->interval, global_task,
                  connect_timeout, lookup, &lookup->timer);
    check_result(result, "isc_timer_create");

    for (query = ISC_LIST_HEAD(lookup->q);
         query != NULL;
         query = ISC_LIST_NEXT(query, link)) {
        query->working = ISC_TRUE;
        query->waiting_connect = ISC_TRUE;
        get_address(query->servname, port, &query->sockaddr);

        sockcount++;
        debug ("Socket = %d",sockcount);
        ENSURE (query->sock == NULL);
        result = isc_socket_create(socketmgr,
                       isc_sockaddr_pf(&query->sockaddr),
                       isc_sockettype_tcp, &query->sock) ;
        check_result(result, "isc_socket_create");
        if (specified_source)
            result = isc_socket_bind(query->sock, &bind_address);
        else {
            if (isc_sockaddr_pf(&query->sockaddr) == AF_INET)
                isc_sockaddr_any(&bind_any);
            else
                isc_sockaddr_any6(&bind_any);
            result = isc_socket_bind(query->sock, &bind_any);
        }
        check_result(result, "isc_socket_bind");
        result = isc_socket_connect(query->sock, &query->sockaddr,
                        global_task, connect_done, query);
        check_result (result, "isc_socket_connect");
    }
}

static void
do_lookup_udp(dig_lookup_t *lookup) {
    dig_query_t *query;
    isc_result_t result;

    debug("do_lookup_udp()");
    if (lookup->tcp_mode)
        debug("I'm starting UDP with tcp_mode set!!!");
    lookup->pending = ISC_TRUE;

    for (query = ISC_LIST_HEAD(lookup->q);
         query != NULL;
         query = ISC_LIST_NEXT(query, link)) {
        query->working = ISC_TRUE;
        query->waiting_connect = ISC_FALSE;
        get_address(query->servname, port, &query->sockaddr);

        sockcount++;
        debug ("Socket = %d",sockcount);
        result = isc_socket_create(socketmgr,
                       isc_sockaddr_pf(&query->sockaddr),
                       isc_sockettype_udp, &query->sock) ;
        check_result(result, "isc_socket_create");
        if (specified_source)
            result = isc_socket_bind(query->sock, &bind_address);
        else {
            if (isc_sockaddr_pf(&query->sockaddr) == AF_INET)
                isc_sockaddr_any(&bind_any);
            else
                isc_sockaddr_any6(&bind_any);
            result = isc_socket_bind(query->sock, &bind_any);
        }
        check_result(result, "isc_socket_bind");
    }

    send_udp(lookup);
}

void
do_lookup(dig_lookup_t *lookup) {

    REQUIRE (lookup != NULL);

    debug ("do_lookup()");
    if (lookup->tcp_mode)
        do_lookup_tcp(lookup);
    else
        do_lookup_udp(lookup);
}

void
start_lookup(void) {
    dig_lookup_t *lookup;

    debug ("start_lookup()");

    if (free_now)
        return;

    lookup = ISC_LIST_HEAD(lookup_list);
    if (lookup != NULL) {
        setup_lookup(lookup);
        do_lookup(lookup);
    }
}

void
free_lists(int _exitcode) {
    void *ptr;
    dig_lookup_t *l;
    dig_query_t *q;
    dig_server_t *s;
    dig_searchlist_t *o;

    debug("free_lists()");

    if (free_now)
        return;

    free_now = ISC_TRUE;

    l = ISC_LIST_HEAD(lookup_list);
    while (l != NULL) {
        if (l->timer != NULL)
            isc_timer_detach (&l->timer);
        q = ISC_LIST_HEAD(l->q);
        while (q != NULL) {
            debug ("Cancelling query %p, belonging to %p",
                   q, l);
            if (q->sock != NULL) {
                isc_socket_cancel(q->sock, NULL,
                          ISC_SOCKCANCEL_ALL);
                isc_socket_detach(&q->sock);
                sockcount--;
                debug ("Socket = %d",sockcount);
            }
            q = ISC_LIST_NEXT(q, link);
        }
        l = ISC_LIST_NEXT(l, link);
    }
    s = ISC_LIST_HEAD(server_list);
    while (s != NULL) {
        debug ("Freeing global server %p", s);
        ptr = s;
        s = ISC_LIST_NEXT(s, link);
        isc_mem_free(mctx, ptr);
    }
    o = ISC_LIST_HEAD(search_list);
    while (o != NULL) {
        debug ("Freeing search %p", o);
        ptr = o;
        o = ISC_LIST_NEXT(o, link);
        isc_mem_free(mctx, ptr);
    }
    if (socketmgr != NULL) {
        debug ("Freeing socketmgr");
        isc_socketmgr_destroy(&socketmgr);
    }
    if (timermgr != NULL) {
        debug ("Freeing timermgr");
        isc_timermgr_destroy(&timermgr);
    }
    if (global_task != NULL) {
        debug ("Freeing task");
        isc_task_detach(&global_task);
    }
    if (taskmgr != NULL) {
        debug ("Freeing taskmgr");
        isc_taskmgr_destroy(&taskmgr);
        }
    if (key != NULL) {
        debug ("Freeing key %p", key);
        dns_tsigkey_setdeleted(key);
        dns_tsigkey_detach(&key);
    }
    if (namebuf != NULL)
        isc_buffer_free(&namebuf);
    if (keyring != NULL) {
        debug ("Freeing keyring %p", keyring);
        dns_tsigkeyring_destroy(&keyring);
    }

    if (is_dst_up) {
        debug ("Destroy DST lib");
        dst_lib_destroy();
        is_dst_up = ISC_FALSE;
    }
    if (entp != NULL) {
        debug ("Detach from entropy");
        isc_entropy_detach(&entp);
    }

    l = ISC_LIST_HEAD(lookup_list);
    while (l != NULL) {
        q = ISC_LIST_HEAD(l->q);
        while (q != NULL) {
            debug ("Freeing query %p, belonging to %p",
                   q, l);
            if (ISC_LINK_LINKED(&q->recvbuf, link))
                ISC_LIST_DEQUEUE(q->recvlist, &q->recvbuf,
                         link);
            if (ISC_LINK_LINKED(&q->lengthbuf, link))
                ISC_LIST_DEQUEUE(q->lengthlist, &q->lengthbuf,
                         link);
            isc_buffer_invalidate(&q->recvbuf);
            isc_buffer_invalidate(&q->lengthbuf);
            ptr = q;
            q = ISC_LIST_NEXT(q, link);
            isc_mem_free(mctx, ptr);
        }
        if (l->use_my_server_list) {
            s = ISC_LIST_HEAD(l->my_server_list);
            while (s != NULL) {
                debug ("Freeing server %p belonging to %p",
                       s, l);
                ptr = s;
                s = ISC_LIST_NEXT(s, link);
                isc_mem_free(mctx, ptr);

            }
        }
        if (l->sendmsg != NULL)
            dns_message_destroy (&l->sendmsg);
        if (l->querysig != NULL) {
            debug ("Freeing buffer %p", l->querysig);
            isc_buffer_free(&l->querysig);
        }

        ptr = l;
        l = ISC_LIST_NEXT(l, link);
        isc_mem_free(mctx, ptr);
    }

    debug("Getting ready to exit, code=%d",_exitcode);
    if (_exitcode != 0)
        exit(_exitcode);
}