/*
 * smallapp/unbound-control.c - remote control utility for unbound.
 *
 * Copyright (c) 2008, NLnet Labs. All rights reserved.
 *
 * This software is open source.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the NLNET LABS nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * \file
 *
 * The remote control utility contacts the unbound server over ssl and
 * sends the command, receives the answer, and displays the result
 * from the commandline.
 */

#include "config.h"
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif
#ifdef HAVE_OPENSSL_SSL_H
#include <openssl/ssl.h>
#endif
#ifdef HAVE_OPENSSL_ERR_H
#include <openssl/err.h>
#endif
#ifdef HAVE_OPENSSL_RAND_H
#include <openssl/rand.h>
#endif
#include "util/log.h"
#include "util/config_file.h"
#include "util/locks.h"
#include "util/net_help.h"
#include "util/shm_side/shm_main.h"
#include "util/timeval_func.h"
#include "daemon/stats.h"
#include "sldns/wire2str.h"
#include "sldns/pkthdr.h"
#include "services/rpz.h"
#include "services/listen_dnsport.h"

#ifdef HAVE_SYS_IPC_H
#include "sys/ipc.h"
#endif
#ifdef HAVE_SYS_SHM_H
#include "sys/shm.h"
#endif
#ifdef HAVE_SYS_UN_H
#include <sys/un.h>
#endif

#ifdef HAVE_TARGETCONDITIONALS_H
#include <TargetConditionals.h>
#endif

static void usage(void) ATTR_NORETURN;
static void ssl_err(const char* s) ATTR_NORETURN;
static void ssl_path_err(const char* s, const char *path) ATTR_NORETURN;

/** timeout to wait for connection over stream, in msec */
#define UNBOUND_CONTROL_CONNECT_TIMEOUT 5000

/** Give unbound-control usage, and exit (1). */
static void
usage(void)
{
        printf("Usage:  unbound-control [options] command\n");
        printf("        Remote control utility for unbound server.\n");
        printf("Options:\n");
        printf("  -c file       config file, default is %s\n", CONFIGFILE);
        printf("  -s ip[@port]  server address, if omitted config is used.\n");
        printf("  -q            quiet (don't print anything if it works ok).\n");
        printf("  -h            show this usage help.\n");
        printf("Commands:\n");
        printf("  start                         start server; runs unbound(8)\n");
        printf("  stop                          stops the server\n");
        printf("  reload                        reloads the server\n");
        printf("                                (this flushes data, stats, requestlist)\n");
        printf("  reload_keep_cache             reloads the server but tries to\n");
        printf("                                keep the RRset and message cache\n");
        printf("                                if (re)configuration allows for it.\n");
        printf("                                That means the caches sizes and\n");
        printf("                                the number of threads must not\n");
        printf("                                change between reloads.\n");
        printf("  fast_reload [+dpv]            reloads the server but only briefly stops\n");
        printf("                                server processing, keeps cache, and changes\n");
        printf("                                most options; check unbound-control(8).\n");
        printf("                +d              drops running queries to keep consistency\n");
        printf("                                on changed options while reloading.\n");
        printf("                +p              does not pause threads for even faster\n");
        printf("                                reload but less options are supported\n");
        printf("                                ; check unbound-control(8).\n");
        printf("                +v              verbose output, it will include duration needed.\n");
        printf("                +vv             more verbose output, it will include memory needed.\n");
        printf("  stats                         print statistics\n");
        printf("  stats_noreset                 peek at statistics\n");
#ifdef HAVE_SHMGET
        printf("  stats_shm                     print statistics using shm\n");
#endif
        printf("  status                        display status of server\n");
        printf("  verbosity <number>            change logging detail\n");
        printf("  log_reopen                    close and open the logfile\n");
        printf("  local_zone <name> <type>      add new local zone\n");
        printf("  local_zone_remove <name>      remove local zone and its contents\n");
        printf("  local_data <RR data...>       add local data, for example\n");
        printf("                                local_data www.example.com A 192.0.2.1\n");
        printf("  local_data_remove <name>      remove local RR data from name\n");
        printf("  local_zones,\n");
        printf("  local_zones_remove,\n");
        printf("  local_datas,\n");
        printf("  local_datas_remove            same, but read list from stdin\n");
        printf("                                (one entry per line).\n");
        printf("  dump_cache                    print cache to stdout\n");
        printf("                                (not supported in remote unbounds in\n");
        printf("                                multi-process operation)\n");
        printf("  load_cache                    load cache from stdin\n");
        printf("                                (not supported in remote unbounds in\n");
        printf("                                multi-process operation)\n");
        printf("  cache_lookup [+t] <names>     print rrsets and msgs at or under the names\n");
        printf("                +t              allow tld and root names.\n");
        printf("  lookup <name>                 print nameservers for name\n");
        printf("  flush [+c] <name>                     flushes common types for name from cache\n");
        printf("                                types:  A, AAAA, MX, PTR, NS,\n");
        printf("                                        SOA, CNAME, DNAME, SRV, NAPTR\n");
        printf("  flush_type [+c] <name> <type> flush name, type from cache\n");
        printf("                +c              remove from cachedb too\n");
        printf("  flush_zone [+c] <name>        flush everything at or under name\n");
        printf("                                from rr and dnssec caches\n");
        printf("  flush_bogus [+c]              flush all bogus data\n");
        printf("  flush_negative [+c]           flush all negative data\n");
        printf("  flush_stats                   flush statistics, make zero\n");
        printf("  flush_requestlist             drop queries that are worked on\n");
        printf("  dump_requestlist              show what is worked on by first thread\n");
        printf("  flush_infra [all | ip]        remove ping, edns for one IP or all\n");
        printf("  dump_infra                    show ping and edns entries\n");
        printf("  set_option opt: val           set option to value, no reload\n");
        printf("  get_option opt                get option value\n");
        printf("  list_stubs                    list stub-zones and root hints in use\n");
        printf("  list_forwards                 list forward-zones in use\n");
        printf("  list_insecure                 list domain-insecure zones\n");
        printf("  list_local_zones              list local-zones in use\n");
        printf("  list_local_data               list local-data RRs in use\n");
        printf("  insecure_add zone             add domain-insecure zone\n");
        printf("  insecure_remove zone          remove domain-insecure zone\n");
        printf("  forward_add [+it] zone addr.. add forward-zone with servers\n");
        printf("  forward_remove [+i] zone      remove forward zone\n");
        printf("  stub_add [+ipt] zone addr..   add stub-zone with servers\n");
        printf("  stub_remove [+i] zone         remove stub zone\n");
        printf("                +i              also do dnssec insecure point\n");
        printf("                +p              set stub to use priming\n");
        printf("                +t              set to use tls upstream\n");
        printf("  forward [off | addr ...]      without arg show forward setup\n");
        printf("                                or off to turn off root forwarding\n");
        printf("                                or give list of ip addresses\n");
        printf("  ratelimit_list [+a]           list ratelimited domains\n");
        printf("  ip_ratelimit_list [+a]        list ratelimited ip addresses\n");
        printf("                +a              list all, also not ratelimited\n");
        printf("  list_auth_zones               list auth zones (includes RPZ zones)\n");
        printf("  auth_zone_reload zone         reload auth zone (or RPZ zone) from zonefile\n");
        printf("  auth_zone_transfer zone       transfer auth zone (or RPZ zone) from master\n");
        printf("  view_list_local_zones view    list local-zones in view\n");
        printf("  view_list_local_data  view    list local-data RRs in view\n");
        printf("  view_local_zone view name type        add local-zone in view\n");
        printf("  view_local_zone_remove view name      remove local-zone in view\n");
        printf("  view_local_data view RR...            add local-data in view\n");
        printf("  view_local_datas view                 add list of local-data to view\n");
        printf("                                        one entry per line read from stdin\n");
        printf("  view_local_data_remove view name      remove local-data in view\n");
        printf("  view_local_datas_remove view          remove list of local-data from view\n");
        printf("                                        one entry per line read from stdin\n");
        printf("  rpz_enable zone               Enable the RPZ zone if it had previously\n");
        printf("                                been disabled\n");
        printf("  rpz_disable zone              Disable the RPZ zone\n");
        printf("  add_cookie_secret <secret>    add (or replace) a new cookie secret <secret>\n");
        printf("  drop_cookie_secret            drop a staging cookie secret\n");
        printf("  activate_cookie_secret        make a staging cookie secret active\n");
        printf("  print_cookie_secrets          show all cookie secrets with their status\n");
        printf("Version %s\n", PACKAGE_VERSION);
        printf("BSD licensed, see LICENSE in source package for details.\n");
        printf("Report bugs to %s\n", PACKAGE_BUGREPORT);
        exit(1);
}

#ifdef HAVE_SHMGET
/** what to put on statistics lines between var and value, ": " or "=" */
#define SQ "="
/** print unsigned long stats value */
#define PR_UL_NM(str, var) printf("%s."str SQ"%lu\n", nm, (unsigned long)(var));
#define PR_UL(str, var) printf(str SQ"%lu\n", (unsigned long)(var));
#define PR_UL_SUB(str, nm, var) printf(str".%s"SQ"%lu\n", nm, (unsigned long)(var));
#define PR_TIMEVAL(str, var) printf(str SQ ARG_LL "d.%6.6d\n", \
        (long long)var.tv_sec, (int)var.tv_usec);
#define PR_STATSTIME(str, var) printf(str SQ ARG_LL "d.%6.6d\n", \
        (long long)var ## _sec, (int)var ## _usec);
#define PR_LL(str, var) printf(str SQ ARG_LL"d\n", (long long)(var));

/** print stat block */
static void pr_stats(const char* nm, struct ub_stats_info* s)
{
        struct timeval sumwait, avg;
        PR_UL_NM("num.queries", s->svr.num_queries);
        PR_UL_NM("num.queries_ip_ratelimited",
                s->svr.num_queries_ip_ratelimited);
        PR_UL_NM("num.queries_cookie_valid",
                s->svr.num_queries_cookie_valid);
        PR_UL_NM("num.queries_cookie_client",
                s->svr.num_queries_cookie_client);
        PR_UL_NM("num.queries_cookie_invalid",
                s->svr.num_queries_cookie_invalid);
        PR_UL_NM("num.queries_discard_timeout",
                s->svr.num_queries_discard_timeout);
        PR_UL_NM("num.queries_replyaddr_limit",
                s->svr.num_queries_replyaddr_limit);
        PR_UL_NM("num.queries_wait_limit", s->svr.num_queries_wait_limit);
        PR_UL_NM("num.cachehits",
                s->svr.num_queries - s->svr.num_queries_missed_cache);
        PR_UL_NM("num.cachemiss", s->svr.num_queries_missed_cache);
        PR_UL_NM("num.prefetch", s->svr.num_queries_prefetch);
        PR_UL_NM("num.queries_timed_out", s->svr.num_queries_timed_out);
        PR_UL_NM("query.queue_time_us.max", s->svr.max_query_time_us);
        PR_UL_NM("num.expired", s->svr.ans_expired);
        PR_UL_NM("num.recursivereplies", s->mesh_replies_sent);
#ifdef USE_DNSCRYPT
        PR_UL_NM("num.dnscrypt.crypted", s->svr.num_query_dnscrypt_crypted);
        PR_UL_NM("num.dnscrypt.cert", s->svr.num_query_dnscrypt_cert);
        PR_UL_NM("num.dnscrypt.cleartext", s->svr.num_query_dnscrypt_cleartext);
        PR_UL_NM("num.dnscrypt.malformed",
                s->svr.num_query_dnscrypt_crypted_malformed);
#endif /* USE_DNSCRYPT */
        PR_UL_NM("num.dns_error_reports", s->svr.num_dns_error_reports);
        printf("%s.requestlist.avg"SQ"%g\n", nm,
                (s->svr.num_queries_missed_cache+s->svr.num_queries_prefetch)?
                        (double)s->svr.sum_query_list_size/
                        (double)(s->svr.num_queries_missed_cache+
                        s->svr.num_queries_prefetch) : 0.0);
        PR_UL_NM("requestlist.max", s->svr.max_query_list_size);
        PR_UL_NM("requestlist.overwritten", s->mesh_jostled);
        PR_UL_NM("requestlist.exceeded", s->mesh_dropped);
        PR_UL_NM("requestlist.current.all", s->mesh_num_states);
        PR_UL_NM("requestlist.current.user", s->mesh_num_reply_states);
        PR_UL_NM("requestlist.current.replies", s->mesh_num_reply_addrs);
#ifndef S_SPLINT_S
        sumwait.tv_sec = s->mesh_replies_sum_wait_sec;
        sumwait.tv_usec = s->mesh_replies_sum_wait_usec;
#endif
        timeval_divide(&avg, &sumwait, s->mesh_replies_sent);
        printf("%s.", nm);
        PR_TIMEVAL("recursion.time.avg", avg);
        printf("%s.recursion.time.median"SQ"%g\n", nm, s->mesh_time_median);
        PR_UL_NM("tcpusage", s->svr.tcp_accept_usage);
}

/** print uptime */
static void print_uptime(struct ub_shm_stat_info* shm_stat)
{
        PR_STATSTIME("time.now", shm_stat->time.now);
        PR_STATSTIME("time.up", shm_stat->time.up);
        PR_STATSTIME("time.elapsed", shm_stat->time.elapsed);
}

/** print memory usage */
static void print_mem(struct ub_shm_stat_info* shm_stat,
        struct ub_stats_info* s)
{
        PR_LL("mem.cache.rrset", shm_stat->mem.rrset);
        PR_LL("mem.cache.message", shm_stat->mem.msg);
        PR_LL("mem.mod.iterator", shm_stat->mem.iter);
        PR_LL("mem.mod.validator", shm_stat->mem.val);
        PR_LL("mem.mod.respip", shm_stat->mem.respip);
#ifdef CLIENT_SUBNET
        PR_LL("mem.mod.subnet", shm_stat->mem.subnet);
#endif
#ifdef USE_IPSECMOD
        PR_LL("mem.mod.ipsecmod", shm_stat->mem.ipsecmod);
#endif
#ifdef WITH_DYNLIBMODULE
        PR_LL("mem.mod.dynlib", shm_stat->mem.dynlib);
#endif
#ifdef USE_DNSCRYPT
        PR_LL("mem.cache.dnscrypt_shared_secret",
                shm_stat->mem.dnscrypt_shared_secret);
        PR_LL("mem.cache.dnscrypt_nonce",
                shm_stat->mem.dnscrypt_nonce);
#endif
        PR_LL("mem.streamwait", s->svr.mem_stream_wait);
        PR_LL("mem.http.query_buffer", s->svr.mem_http2_query_buffer);
        PR_LL("mem.http.response_buffer", s->svr.mem_http2_response_buffer);
#ifdef HAVE_NGTCP2
        PR_LL("mem.quic", s->svr.mem_quic);
#endif
}

/** print histogram */
static void print_hist(struct ub_stats_info* s)
{
        struct timehist* hist;
        size_t i;
        hist = timehist_setup();
        if(!hist)
                fatal_exit("out of memory");
        timehist_import(hist, s->svr.hist, NUM_BUCKETS_HIST);
        for(i=0; i<hist->num; i++) {
                printf("histogram.%6.6d.%6.6d.to.%6.6d.%6.6d=%lu\n",
                        (int)hist->buckets[i].lower.tv_sec,
                        (int)hist->buckets[i].lower.tv_usec,
                        (int)hist->buckets[i].upper.tv_sec,
                        (int)hist->buckets[i].upper.tv_usec,
                        (unsigned long)hist->buckets[i].count);
        }
        timehist_delete(hist);
}

/** print extended */
static void print_extended(struct ub_stats_info* s, int inhibit_zero)
{
        int i;
        char nm[16];

        /* TYPE */
        for(i=0; i<UB_STATS_QTYPE_NUM; i++) {
                if(inhibit_zero && s->svr.qtype[i] == 0)
                        continue;
                sldns_wire2str_type_buf((uint16_t)i, nm, sizeof(nm));
                PR_UL_SUB("num.query.type", nm, s->svr.qtype[i]);
        }
        if(!inhibit_zero || s->svr.qtype_big) {
                PR_UL("num.query.type.other", s->svr.qtype_big);
        }

        /* CLASS */
        for(i=0; i<UB_STATS_QCLASS_NUM; i++) {
                if(inhibit_zero && s->svr.qclass[i] == 0)
                        continue;
                sldns_wire2str_class_buf((uint16_t)i, nm, sizeof(nm));
                PR_UL_SUB("num.query.class", nm, s->svr.qclass[i]);
        }
        if(!inhibit_zero || s->svr.qclass_big) {
                PR_UL("num.query.class.other", s->svr.qclass_big);
        }

        /* OPCODE */
        for(i=0; i<UB_STATS_OPCODE_NUM; i++) {
                if(inhibit_zero && s->svr.qopcode[i] == 0)
                        continue;
                sldns_wire2str_opcode_buf(i, nm, sizeof(nm));
                PR_UL_SUB("num.query.opcode", nm, s->svr.qopcode[i]);
        }

        /* transport */
        PR_UL("num.query.tcp", s->svr.qtcp);
        PR_UL("num.query.tcpout", s->svr.qtcp_outgoing);
        PR_UL("num.query.udpout", s->svr.qudp_outgoing);
        PR_UL("num.query.tls", s->svr.qtls);
        PR_UL("num.query.tls_resume", s->svr.qtls_resume);
        PR_UL("num.query.ipv6", s->svr.qipv6);
        PR_UL("num.query.https", s->svr.qhttps);
#ifdef HAVE_NGTCP2
        PR_UL("num.query.quic", s->svr.qquic);
#endif

        /* flags */
        PR_UL("num.query.flags.QR", s->svr.qbit_QR);
        PR_UL("num.query.flags.AA", s->svr.qbit_AA);
        PR_UL("num.query.flags.TC", s->svr.qbit_TC);
        PR_UL("num.query.flags.RD", s->svr.qbit_RD);
        PR_UL("num.query.flags.RA", s->svr.qbit_RA);
        PR_UL("num.query.flags.Z", s->svr.qbit_Z);
        PR_UL("num.query.flags.AD", s->svr.qbit_AD);
        PR_UL("num.query.flags.CD", s->svr.qbit_CD);
        PR_UL("num.query.edns.present", s->svr.qEDNS);
        PR_UL("num.query.edns.DO", s->svr.qEDNS_DO);

        /* RCODE */
        for(i=0; i<UB_STATS_RCODE_NUM; i++) {
                /* Always include RCODEs 0-5 */
                if(inhibit_zero && i > LDNS_RCODE_REFUSED && s->svr.ans_rcode[i] == 0)
                        continue;
                sldns_wire2str_rcode_buf(i, nm, sizeof(nm));
                PR_UL_SUB("num.answer.rcode", nm, s->svr.ans_rcode[i]);
        }
        if(!inhibit_zero || s->svr.ans_rcode_nodata) {
                PR_UL("num.answer.rcode.nodata", s->svr.ans_rcode_nodata);
        }
        /* iteration */
        PR_UL("num.query.ratelimited", s->svr.queries_ratelimited);
        /* validation */
        PR_UL("num.answer.secure", s->svr.ans_secure);
        PR_UL("num.answer.bogus", s->svr.ans_bogus);
        PR_UL("num.rrset.bogus", s->svr.rrset_bogus);
        PR_UL("num.valops", s->svr.val_ops);
        PR_UL("num.query.aggressive.NOERROR", s->svr.num_neg_cache_noerror);
        PR_UL("num.query.aggressive.NXDOMAIN", s->svr.num_neg_cache_nxdomain);
        /* threat detection */
        PR_UL("unwanted.queries", s->svr.unwanted_queries);
        PR_UL("unwanted.replies", s->svr.unwanted_replies);
        /* cache counts */
        PR_UL("msg.cache.count", s->svr.msg_cache_count);
        PR_UL("rrset.cache.count", s->svr.rrset_cache_count);
        PR_UL("infra.cache.count", s->svr.infra_cache_count);
        PR_UL("key.cache.count", s->svr.key_cache_count);
        /* max collisions */
        PR_UL("msg.cache.max_collisions", s->svr.msg_cache_max_collisions);
        PR_UL("rrset.cache.max_collisions", s->svr.rrset_cache_max_collisions);
        /* applied RPZ actions */
        for(i=0; i<UB_STATS_RPZ_ACTION_NUM; i++) {
                if(i == RPZ_NO_OVERRIDE_ACTION)
                        continue;
                if(inhibit_zero && s->svr.rpz_action[i] == 0)
                        continue;
                PR_UL_SUB("num.rpz.action", rpz_action_to_string(i), s->svr.rpz_action[i]);
        }
#ifdef USE_DNSCRYPT
        PR_UL("dnscrypt_shared_secret.cache.count",
                         s->svr.shared_secret_cache_count);
        PR_UL("num.query.dnscrypt.shared_secret.cachemiss",
                         s->svr.num_query_dnscrypt_secret_missed_cache);
        PR_UL("dnscrypt_nonce.cache.count", s->svr.nonce_cache_count);
        PR_UL("num.query.dnscrypt.replay",
                         s->svr.num_query_dnscrypt_replay);
#endif /* USE_DNSCRYPT */
        PR_UL("num.query.authzone.up", s->svr.num_query_authzone_up);
        PR_UL("num.query.authzone.down", s->svr.num_query_authzone_down);
#ifdef CLIENT_SUBNET
        PR_UL("num.query.subnet", s->svr.num_query_subnet);
        PR_UL("num.query.subnet_cache", s->svr.num_query_subnet_cache);
#endif
#ifdef USE_CACHEDB
        PR_UL("num.query.cachedb", s->svr.num_query_cachedb);
#endif
}

/** print statistics out of memory structures */
static void do_stats_shm(struct config_file* cfg, struct ub_stats_info* stats,
        struct ub_shm_stat_info* shm_stat)
{
        int i;
        char nm[32];
        for(i=0; i<cfg->num_threads; i++) {
                snprintf(nm, sizeof(nm), "thread%d", i);
                pr_stats(nm, &stats[i+1]);
        }
        pr_stats("total", &stats[0]);
        print_uptime(shm_stat);
        if(cfg->stat_extended) {
                print_mem(shm_stat, &stats[0]);
                print_hist(stats);
                print_extended(stats, cfg->stat_inhibit_zero);
        }
}
#endif /* HAVE_SHMGET */

/** print statistics from shm memory segment */
static void print_stats_shm(const char* cfgfile, int quiet)
{
#ifdef HAVE_SHMGET
        struct config_file* cfg;
        struct ub_stats_info* stats;
        struct ub_shm_stat_info* shm_stat;
        int id_ctl, id_arr;
        /* read config */
        if(!(cfg = config_create()))
                fatal_exit("out of memory");
        if(!config_read(cfg, cfgfile, NULL))
                fatal_exit("could not read config file");
        /* get shm segments */
        id_ctl = shmget(cfg->shm_key, sizeof(int), SHM_R);
        if(id_ctl == -1) {
                fatal_exit("shmget(%d): %s", cfg->shm_key, strerror(errno));
        }
        id_arr = shmget(cfg->shm_key+1, sizeof(int), SHM_R);
        if(id_arr == -1) {
                fatal_exit("shmget(%d): %s", cfg->shm_key+1, strerror(errno));
        }
        shm_stat = (struct ub_shm_stat_info*)shmat(id_ctl, NULL, SHM_RDONLY);
        if(shm_stat == (void*)-1) {
                fatal_exit("shmat(%d): %s", id_ctl, strerror(errno));
        }
        stats = (struct ub_stats_info*)shmat(id_arr, NULL, SHM_RDONLY);
        if(stats == (void*)-1) {
                fatal_exit("shmat(%d): %s", id_arr, strerror(errno));
        }


        if(!quiet) {
                /* print the stats */
                do_stats_shm(cfg, stats, shm_stat);
        }

        /* shutdown */
        shmdt(shm_stat);
        shmdt(stats);
        config_delete(cfg);
#else
        (void)cfgfile;
        (void)quiet;
#endif /* HAVE_SHMGET */
}

/** exit with ssl error */
static void ssl_err(const char* s)
{
        fprintf(stderr, "error: %s\n", s);
        ERR_print_errors_fp(stderr);
        exit(1);
}

/** exit with ssl error related to a file path */
static void ssl_path_err(const char* s, const char *path)
{
        unsigned long err;
        err = ERR_peek_error();
        if(ERR_GET_LIB(err) == ERR_LIB_SYS) {
                fprintf(stderr, "error: %s\n%s: %s\n",
                        s, path, ERR_reason_error_string(err));
                exit(1);
        } else {
                ssl_err(s);
        }
}

/** setup SSL context */
static SSL_CTX*
setup_ctx(struct config_file* cfg)
{
        char* s_cert=NULL, *c_key=NULL, *c_cert=NULL;
        SSL_CTX* ctx;

        if(!(options_remote_is_address(cfg) && cfg->control_use_cert))
                return NULL;
        s_cert = fname_after_chroot(cfg->server_cert_file, cfg, 1);
        c_key = fname_after_chroot(cfg->control_key_file, cfg, 1);
        c_cert = fname_after_chroot(cfg->control_cert_file, cfg, 1);
        if(!s_cert || !c_key || !c_cert)
                fatal_exit("out of memory");
        ctx = SSL_CTX_new(SSLv23_client_method());
        if(!ctx)
                ssl_err("could not allocate SSL_CTX pointer");
#if SSL_OP_NO_SSLv2 != 0
        if((SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv2) & SSL_OP_NO_SSLv2)
                != SSL_OP_NO_SSLv2)
                ssl_err("could not set SSL_OP_NO_SSLv2");
#endif
        if((SSL_CTX_set_options(ctx, SSL_OP_NO_SSLv3) & SSL_OP_NO_SSLv3)
                != SSL_OP_NO_SSLv3)
                ssl_err("could not set SSL_OP_NO_SSLv3");
#if defined(SSL_OP_NO_RENEGOTIATION)
        /* disable client renegotiation */
        if((SSL_CTX_set_options(ctx, SSL_OP_NO_RENEGOTIATION) &
                SSL_OP_NO_RENEGOTIATION) != SSL_OP_NO_RENEGOTIATION)
                ssl_err("could not set SSL_OP_NO_RENEGOTIATION");
#endif
        if(!SSL_CTX_use_certificate_chain_file(ctx,c_cert))
                ssl_path_err("Error setting up SSL_CTX client cert", c_cert);
        if(!SSL_CTX_use_PrivateKey_file(ctx,c_key,SSL_FILETYPE_PEM))
                ssl_path_err("Error setting up SSL_CTX client key", c_key);
        if(!SSL_CTX_check_private_key(ctx))
                ssl_err("Error setting up SSL_CTX client key");
        if(SSL_CTX_load_verify_locations(ctx, s_cert, NULL) != 1)
                ssl_path_err("Error setting up SSL_CTX verify, server cert",
                             s_cert);
        SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);

        free(s_cert);
        free(c_key);
        free(c_cert);
        return ctx;
}

/** check connect error */
static void
checkconnecterr(int err, const char* svr, struct sockaddr_storage* addr,
        socklen_t addrlen, int statuscmd, int useport)
{
#ifndef USE_WINSOCK
        if(!useport) log_err("connect: %s for %s", strerror(err), svr);
        else log_err_addr("connect", strerror(err), addr, addrlen);
        if(err == ECONNREFUSED && statuscmd) {
                printf("unbound is stopped\n");
                exit(3);
        }
#else
        int wsaerr = err;
        if(!useport) log_err("connect: %s for %s", wsa_strerror(wsaerr), svr);
        else log_err_addr("connect", wsa_strerror(wsaerr), addr, addrlen);
        if(wsaerr == WSAECONNREFUSED && statuscmd) {
                printf("unbound is stopped\n");
                exit(3);
        }
#endif
        exit(1);
}

/** contact the server with TCP connect */
static int
contact_server(const char* svr, struct config_file* cfg, int statuscmd)
{
        struct sockaddr_storage addr;
        socklen_t addrlen;
        int addrfamily = 0, proto = IPPROTO_TCP;
        int fd, useport = 1;
        char** rcif = NULL;
        int num_rcif = 0;
        /* use svr or the first config entry */
        if(!svr) {
                if(cfg->control_ifs.first) {
                        struct sockaddr_storage addr2;
                        socklen_t addrlen2;
                        if(extstrtoaddr(cfg->control_ifs.first->str, &addr2,
                                &addrlen2, UNBOUND_DNS_PORT)) {
                                svr = cfg->control_ifs.first->str;
                        } else {
                                if(!resolve_interface_names(NULL, 0,
                                        cfg->control_ifs.first, &rcif,
                                        &num_rcif)) {
                                        fatal_exit("could not resolve interface names");
                                }
                                if(rcif == NULL || num_rcif == 0) {
                                        fatal_exit("no control interfaces");
                                }
                                svr = rcif[0];
                        }
                } else if(cfg->do_ip4) {
                        svr = "127.0.0.1";
                } else {
                        svr = "::1";
                }
                /* config 0 addr (everything), means ask localhost */
                if(strcmp(svr, "0.0.0.0") == 0)
                        svr = "127.0.0.1";
                else if(strcmp(svr, "::0") == 0 ||
                        strcmp(svr, "0::0") == 0 ||
                        strcmp(svr, "0::") == 0 ||
                        strcmp(svr, "::") == 0)
                        svr = "::1";
        }
        if(strchr(svr, '@')) {
                if(!extstrtoaddr(svr, &addr, &addrlen, UNBOUND_DNS_PORT))
                        fatal_exit("could not parse IP@port: %s", svr);
#ifdef HAVE_SYS_UN_H
        } else if(svr[0] == '/') {
                struct sockaddr_un* usock = (struct sockaddr_un *) &addr;
                usock->sun_family = AF_LOCAL;
#ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
                usock->sun_len = (unsigned)sizeof(usock);
#endif
                (void)strlcpy(usock->sun_path, svr, sizeof(usock->sun_path));
                addrlen = (socklen_t)sizeof(struct sockaddr_un);
                addrfamily = AF_LOCAL;
                useport = 0;
                proto = 0;
#endif
        } else {
                if(!ipstrtoaddr(svr, cfg->control_port, &addr, &addrlen))
                        fatal_exit("could not parse IP: %s", svr);
        }

        if(addrfamily == 0)
                addrfamily = addr_is_ip6(&addr, addrlen)?PF_INET6:PF_INET;
        fd = socket(addrfamily, SOCK_STREAM, proto);
        if(fd == -1) {
                fatal_exit("socket: %s", sock_strerror(errno));
        }
        fd_set_nonblock(fd);
        if(connect(fd, (struct sockaddr*)&addr, addrlen) < 0) {
#ifndef USE_WINSOCK
#ifdef EINPROGRESS
                if(errno != EINPROGRESS) {
                        checkconnecterr(errno, svr, &addr,
                                addrlen, statuscmd, useport);
                }
#endif
#else
                if(WSAGetLastError() != WSAEINPROGRESS &&
                        WSAGetLastError() != WSAEWOULDBLOCK) {
                        checkconnecterr(WSAGetLastError(), svr, &addr,
                                addrlen, statuscmd, useport);
                }
#endif
        }
        while(1) {
                fd_set rset, wset, eset;
                struct timeval tv;
                FD_ZERO(&rset);
                FD_SET(FD_SET_T fd, &rset);
                FD_ZERO(&wset);
                FD_SET(FD_SET_T fd, &wset);
                FD_ZERO(&eset);
                FD_SET(FD_SET_T fd, &eset);
                tv.tv_sec = UNBOUND_CONTROL_CONNECT_TIMEOUT/1000;
                tv.tv_usec= (UNBOUND_CONTROL_CONNECT_TIMEOUT%1000)*1000;
                if(select(fd+1, &rset, &wset, &eset, &tv) == -1) {
                        fatal_exit("select: %s", sock_strerror(errno));
                }
                if(!FD_ISSET(fd, &rset) && !FD_ISSET(fd, &wset) &&
                        !FD_ISSET(fd, &eset)) {
                        fatal_exit("timeout: could not connect to server");
                } else {
                        /* check nonblocking connect error */
                        int error = 0;
                        socklen_t len = (socklen_t)sizeof(error);
                        if(getsockopt(fd, SOL_SOCKET, SO_ERROR, (void*)&error,
                                &len) < 0) {
#ifndef USE_WINSOCK
                                error = errno; /* on solaris errno is error */
#else
                                error = WSAGetLastError();
#endif
                        }
                        if(error != 0) {
#ifndef USE_WINSOCK
#ifdef EINPROGRESS
                                if(error == EINPROGRESS)
                                        continue; /* try again later */
#endif
#ifdef EWOULDBLOCK
                                if(error == EWOULDBLOCK)
                                        continue; /* try again later */
#endif
#else
                                if(error == WSAEINPROGRESS)
                                        continue; /* try again later */
                                if(error == WSAEWOULDBLOCK)
                                        continue; /* try again later */
#endif
                                checkconnecterr(error, svr, &addr, addrlen,
                                        statuscmd, useport);
                        }
                }
                break;
        }
        fd_set_block(fd);
        config_del_strarray(rcif, num_rcif);
        return fd;
}

/** setup SSL on the connection */
static SSL*
setup_ssl(SSL_CTX* ctx, int fd)
{
        SSL* ssl;
        X509* x;
        int r;

        if(!ctx) return NULL;
        ssl = SSL_new(ctx);
        if(!ssl)
                ssl_err("could not SSL_new");
        SSL_set_connect_state(ssl);
        (void)SSL_set_mode(ssl, (long)SSL_MODE_AUTO_RETRY);
        if(!SSL_set_fd(ssl, fd))
                ssl_err("could not SSL_set_fd");
        while(1) {
                ERR_clear_error();
                if( (r=SSL_do_handshake(ssl)) == 1)
                        break;
                r = SSL_get_error(ssl, r);
                if(r != SSL_ERROR_WANT_READ && r != SSL_ERROR_WANT_WRITE)
                        ssl_err("SSL handshake failed");
                /* wants to be called again */
        }

        /* check authenticity of server */
        if(SSL_get_verify_result(ssl) != X509_V_OK)
                ssl_err("SSL verification failed");
#ifdef HAVE_SSL_GET1_PEER_CERTIFICATE
        x = SSL_get1_peer_certificate(ssl);
#else
        x = SSL_get_peer_certificate(ssl);
#endif
        if(!x)
                ssl_err("Server presented no peer certificate");
        X509_free(x);

        return ssl;
}

/** read from ssl or fd, fatalexit on error, 0 EOF, 1 success */
static int
remote_read(SSL* ssl, int fd, char* buf, size_t len)
{
        if(ssl) {
                int r;
                ERR_clear_error();
                if((r = SSL_read(ssl, buf, (int)len-1)) <= 0) {
                        if(SSL_get_error(ssl, r) == SSL_ERROR_ZERO_RETURN) {
                                /* EOF */
                                return 0;
                        }
                        ssl_err("could not SSL_read");
                }
                buf[r] = 0;
        } else {
                ssize_t rr = recv(fd, buf, len-1, 0);
                if(rr <= 0) {
                        if(rr == 0) {
                                /* EOF */
                                return 0;
                        }
                        fatal_exit("could not recv: %s", sock_strerror(errno));
                }
                buf[rr] = 0;
        }
        return 1;
}

/** write to ssl or fd, fatalexit on error */
static void
remote_write(SSL* ssl, int fd, const char* buf, size_t len)
{
        if(ssl) {
                if(SSL_write(ssl, buf, (int)len) <= 0)
                        ssl_err("could not SSL_write");
        } else {
                if(send(fd, buf, len, 0) < (ssize_t)len) {
                        fatal_exit("could not send: %s", sock_strerror(errno));
                }
        }
}

/** check args, to see if too many args. Because when a file is sent it
 * would wait for the terminal, and we can check for too many arguments,
 * eg. user put arguments on the commandline. */
static void
check_args_for_listcmd(int argc, char* argv[])
{
        if(argc >= 1 && (strcmp(argv[0], "local_zones") == 0 ||
                strcmp(argv[0], "local_zones_remove") == 0 ||
                strcmp(argv[0], "local_datas") == 0 ||
                strcmp(argv[0], "local_datas_remove") == 0) &&
                argc >= 2) {
                fatal_exit("too many arguments for command '%s', "
                        "content is piped in from stdin", argv[0]);
        }
        if(argc >= 1 && (strcmp(argv[0], "view_local_datas") == 0 ||
                strcmp(argv[0], "view_local_datas_remove") == 0) &&
                argc >= 3) {
                fatal_exit("too many arguments for command '%s', "
                        "content is piped in from stdin", argv[0]);
        }
}

/** send stdin to server */
static void
send_file(SSL* ssl, int fd, FILE* in, char* buf, size_t sz)
{
        while(fgets(buf, (int)sz, in)) {
                remote_write(ssl, fd, buf, strlen(buf));
        }
}

/** send end-of-file marker to server */
static void
send_eof(SSL* ssl, int fd)
{
        char e[] = {0x04, 0x0a};
        remote_write(ssl, fd, e, sizeof(e));
}

/** send command and display result */
static int
go_cmd(SSL* ssl, int fd, int quiet, int argc, char* argv[])
{
        char pre[10];
        const char* space=" ";
        const char* newline="\n";
        int was_error = 0, first_line = 1;
        int i;
        char buf[1024];
        snprintf(pre, sizeof(pre), "UBCT%d ", UNBOUND_CONTROL_VERSION);
        remote_write(ssl, fd, pre, strlen(pre));
        for(i=0; i<argc; i++) {
                remote_write(ssl, fd, space, strlen(space));
                remote_write(ssl, fd, argv[i], strlen(argv[i]));
        }
        remote_write(ssl, fd, newline, strlen(newline));

        if(argc == 1 && strcmp(argv[0], "load_cache") == 0) {
                send_file(ssl, fd, stdin, buf, sizeof(buf));
        }
        else if(argc >= 1 && (strcmp(argv[0], "local_zones") == 0 ||
                strcmp(argv[0], "local_zones_remove") == 0 ||
                strcmp(argv[0], "local_datas") == 0 ||
                strcmp(argv[0], "view_local_datas") == 0 ||
                strcmp(argv[0], "local_datas_remove") == 0 ||
                strcmp(argv[0], "view_local_datas_remove") == 0)) {
                send_file(ssl, fd, stdin, buf, sizeof(buf));
                send_eof(ssl, fd);
        }

        while(1) {
                if(remote_read(ssl, fd, buf, sizeof(buf)) == 0) {
                        break; /* EOF */
                }
                if(first_line && strncmp(buf, "error", 5) == 0) {
                        printf("%s", buf);
                        was_error = 1;
                } else if(!quiet) {
                        printf("%s", buf);
                }

                first_line = 0;
        }
        return was_error;
}

/** go ahead and read config, contact server and perform command and display */
static int
go(const char* cfgfile, char* svr, int quiet, int argc, char* argv[])
{
        struct config_file* cfg;
        int fd, ret;
        SSL_CTX* ctx;
        SSL* ssl;

        /* read config */
        if(!(cfg = config_create()))
                fatal_exit("out of memory");
        if(!config_read(cfg, cfgfile, NULL))
                fatal_exit("could not read config file");
        if(!cfg->remote_control_enable)
                log_warn("control-enable is 'no' in the config file.");
#ifdef UB_ON_WINDOWS
        w_config_adjust_directory(cfg);
#endif
        ctx = setup_ctx(cfg);

        /* contact server */
        fd = contact_server(svr, cfg, argc>0&&strcmp(argv[0],"status")==0);
        ssl = setup_ssl(ctx, fd);

        /* send command */
        ret = go_cmd(ssl, fd, quiet, argc, argv);

        if(ssl) SSL_free(ssl);
        sock_close(fd);
        if(ctx) SSL_CTX_free(ctx);
        config_delete(cfg);
        return ret;
}

/** getopt global, in case header files fail to declare it. */
extern int optind;
/** getopt global, in case header files fail to declare it. */
extern char* optarg;

/** Main routine for unbound-control */
int main(int argc, char* argv[])
{
        int c, ret;
        int quiet = 0;
        const char* cfgfile = CONFIGFILE;
        char* svr = NULL;
#ifdef USE_WINSOCK
        int r;
        WSADATA wsa_data;
#endif
#ifdef USE_THREAD_DEBUG
        /* stop the file output from unbound-control, overwrites the servers */
        extern int check_locking_order;
        check_locking_order = 0;
#endif /* USE_THREAD_DEBUG */
        checklock_start();
        log_ident_set("unbound-control");
        log_init(NULL, 0, NULL);
#ifdef USE_WINSOCK
        /* use registry config file in preference to compiletime location */
        if(!(cfgfile=w_lookup_reg_str("Software\\Unbound", "ConfigFile")))
                cfgfile = CONFIGFILE;
#endif
        /* parse the options */
        while( (c=getopt(argc, argv, "c:s:qh")) != -1) {
                switch(c) {
                case 'c':
                        cfgfile = optarg;
                        break;
                case 's':
                        svr = optarg;
                        break;
                case 'q':
                        quiet = 1;
                        break;
                case '?':
                case 'h':
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if(argc == 0)
                usage();
        if(argc >= 1 && strcmp(argv[0], "start")==0) {
#if (defined(TARGET_OS_TV) && TARGET_OS_TV) || (defined(TARGET_OS_WATCH) && TARGET_OS_WATCH)
                fatal_exit("could not exec unbound: %s",
                        strerror(ENOSYS));
#else
                if(execlp("unbound", "unbound", "-c", cfgfile,
                        (char*)NULL) < 0) {
                        fatal_exit("could not exec unbound: %s",
                                strerror(errno));
                }
#endif
        }
        if(argc >= 1 && strcmp(argv[0], "stats_shm")==0) {
                print_stats_shm(cfgfile, quiet);
                return 0;
        }
        check_args_for_listcmd(argc, argv);

#ifdef USE_WINSOCK
        if((r = WSAStartup(MAKEWORD(2,2), &wsa_data)) != 0)
                fatal_exit("WSAStartup failed: %s", wsa_strerror(r));
#endif

#ifdef HAVE_ERR_LOAD_CRYPTO_STRINGS
        ERR_load_crypto_strings();
#endif
#if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL)
        ERR_load_SSL_strings();
#endif
#if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_CRYPTO)
#  ifndef S_SPLINT_S
        OpenSSL_add_all_algorithms();
#  endif
#else
        OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
                | OPENSSL_INIT_ADD_ALL_DIGESTS
                | OPENSSL_INIT_LOAD_CRYPTO_STRINGS
#  if defined(OPENSSL_INIT_NO_LOAD_CONFIG) && defined(UB_ON_WINDOWS)
                | OPENSSL_INIT_NO_LOAD_CONFIG
#  endif
                , NULL);
#endif
#if OPENSSL_VERSION_NUMBER < 0x10100000 || !defined(HAVE_OPENSSL_INIT_SSL)
        (void)SSL_library_init();
#else
        (void)OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS
#  if defined(OPENSSL_INIT_NO_LOAD_CONFIG) && defined(UB_ON_WINDOWS)
                | OPENSSL_INIT_NO_LOAD_CONFIG
#  endif
                , NULL);
#endif

        if(!RAND_status()) {
                /* try to seed it */
                unsigned char buf[256];
                unsigned int seed=(unsigned)time(NULL) ^ (unsigned)getpid();
                unsigned int v = seed;
                size_t i;
                for(i=0; i<256/sizeof(v); i++) {
                        memmove(buf+i*sizeof(v), &v, sizeof(v));
                        v = v*seed + (unsigned int)i;
                }
                RAND_seed(buf, 256);
                log_warn("no entropy, seeding openssl PRNG with time\n");
        }

        ret = go(cfgfile, svr, quiet, argc, argv);

#ifdef USE_WINSOCK
        WSACleanup();
#endif
        checklock_stop();
        return ret;
}