net/adblock/files/adblock.sh

   1 #!/bin/sh
   2 # dns based ad/abuse domain blocking
   3 # written by Dirk Brenken (dev@brenken.org)
   4
   5 # This is free software, licensed under the GNU General Public License v3.
   6 # You should have received a copy of the GNU General Public License
   7 # along with this program. If not, see <http://www.gnu.org/licenses/>.
   8
   9 # set initial defaults
  10 #
  11 LC_ALL=C
  12 PATH="/usr/sbin:/usr/bin:/sbin:/bin"
  13 adb_ver="2.8.5"
  14 adb_sysver="$(ubus -S call system board | jsonfilter -e '@.release.description')"
  15 adb_enabled=1
  16 adb_debug=0
  17 adb_minfree=2
  18 adb_manmode=0
  19 adb_forcesrt=0
  20 adb_forcedns=0
  21 adb_backup=0
  22 adb_backupdir="/mnt"
  23 adb_whitelist="/etc/adblock/adblock.whitelist"
  24 adb_whitelist_rset="\$1 ~/^([A-Za-z0-9_-]+\.){1,}[A-Za-z]+/{print tolower(\"^\"\$1\"\\\|[.]\"\$1)}"
  25 adb_fetch="/usr/bin/wget"
  26 adb_fetchparm="--quiet --no-cache --no-cookies --max-redirect=0 --timeout=10 --no-check-certificate -O"
  27 adb_dnslist="dnsmasq unbound named kresd"
  28 adb_dnsprefix="adb_list"
  29 adb_dnsfile="${adb_dnsprefix}.overall"
  30 adb_rtfile="/tmp/adb_runtime.json"
  31 adb_sources=""
  32 adb_src_cat_shalla=""
  33 adb_action="${1}"
  34
  35 # f_envload: load adblock environment
  36 #
  37 f_envload()
  38 {
  39     local services dns_up cnt=0
  40
  41     # source in system libraries
  42     #
  43     if [ -r "/lib/functions.sh" ] && [ -r "/usr/share/libubox/jshn.sh" ]
  44     then
  45         . "/lib/functions.sh"
  46         . "/usr/share/libubox/jshn.sh"
  47     else
  48         f_log "error" "system libraries not found"
  49     fi
  50
  51     # parse global section by callback
  52     #
  53     config_cb()
  54     {
  55         local type="${1}"
  56         if [ "${type}" = "adblock" ]
  57         then
  58             option_cb()
  59             {
  60                 local option="${1}"
  61                 local value="${2}"
  62                 eval "${option}=\"${value}\""
  63             }
  64         else
  65             reset_cb
  66         fi
  67     }
  68
  69     # parse 'source' sections
  70     #
  71     parse_config()
  72     {
  73         local value opt section="${1}" options="enabled adb_src adb_src_rset adb_src_cat"
  74         eval "adb_sources=\"${adb_sources} ${section}\""
  75         for opt in ${options}
  76         do
  77             config_get value "${section}" "${opt}"
  78             if [ -n "${value}" ]
  79             then
  80                 eval "${opt}_${section}=\"${value}\""
  81             fi
  82         done
  83     }
  84
  85     # load adblock config
  86     #
  87     config_load adblock
  88     config_foreach parse_config source
  89
  90     # set dns backend environment
  91     #
  92     while [ ${cnt} -le 20 ]
  93     do
  94         services="$(ubus -S call service list 2>/dev/null)"
  95         if [ -n "${services}" ]
  96         then
  97             for dns in ${adb_dnslist}
  98             do
  99                 dns_up="$(printf "%s" "${services}" | jsonfilter -l1 -e "@.${dns}.instances.*.running")"
 100                 if [ "${dns_up}" = "true" ]
 101                 then
 102                     case "${dns}" in
 103                         dnsmasq)
 104                             adb_dns="${dns}"
 105                             adb_dnsdir="${adb_dnsdir:="/tmp/dnsmasq.d"}"
 106                             adb_dnshidedir="${adb_dnsdir}/.adb_hidden"
 107                             adb_dnsformat="awk '{print \"local=/\"\$0\"/\"}'"
 108                             break 2
 109                             ;;
 110                         unbound)
 111                             adb_dns="${dns}"
 112                             adb_dnsdir="${adb_dnsdir:="/var/lib/unbound"}"
 113                             adb_dnshidedir="${adb_dnsdir}/.adb_hidden"
 114                             adb_dnsformat="awk '{print \"local-zone: \042\"\$0\"\042 static\"}'"
 115                             break 2
 116                             ;;
 117                         named)
 118                             adb_dns="${dns}"
 119                             adb_dnsdir="${adb_dnsdir:="/var/lib/bind"}"
 120                             adb_dnshidedir="${adb_dnsdir}/.adb_hidden"
 121                             adb_dnsformat="awk '{print \"\"\$0\" IN CNAME .\n*.\"\$0\" IN CNAME .\"}'"
 122                             break 2
 123                             ;;
 124                         kresd)
 125                             adb_dns="${dns}"
 126                             adb_dnsdir="${adb_dnsdir:="/tmp/kresd"}"
 127                             adb_dnshidedir="${adb_dnsdir}/.adb_hidden"
 128                             adb_dnsformat="awk '{print \"\"\$0\" CNAME .\n*.\"\$0\" CNAME .\"}'"
 129                             break 2
 130                             ;;
 131                     esac
 132                 fi
 133             done
 134         fi
 135         sleep 1
 136         cnt=$((cnt+1))
 137     done
 138     if [ -z "${adb_dns}" ] || [ -z "${adb_dnsformat}" ] || [ ! -x "$(command -v ${adb_dns})" ] || [ ! -d "${adb_dnsdir}" ]
 139     then
 140         f_log "error" "no active/supported DNS backend found"
 141     fi
 142
 143     # force dns to local resolver
 144     #
 145     if [ ${adb_forcedns} -eq 1 ] && [ -z "$(uci -q get firewall.adblock_dns)" ]
 146     then
 147         uci -q set firewall.adblock_dns="redirect"
 148         uci -q set firewall.adblock_dns.name="Adblock DNS"
 149         uci -q set firewall.adblock_dns.src="lan"
 150         uci -q set firewall.adblock_dns.proto="tcp udp"
 151         uci -q set firewall.adblock_dns.src_dport="53"
 152         uci -q set firewall.adblock_dns.dest_port="53"
 153         uci -q set firewall.adblock_dns.target="DNAT"
 154     elif [ ${adb_forcedns} -eq 0 ] && [ -n "$(uci -q get firewall.adblock_dns)" ]
 155     then
 156         uci -q delete firewall.adblock_dns
 157     fi
 158     if [ -n "$(uci -q changes firewall)" ]
 159     then
 160         uci -q commit firewall
 161         if [ $(/etc/init.d/firewall enabled; printf "%u" ${?}) -eq 0 ]
 162         then
 163             /etc/init.d/firewall reload >/dev/null 2>&1
 164         fi
 165     fi
 166 }
 167
 168 # f_envcheck: check/set environment prerequisites
 169 #
 170 f_envcheck()
 171 {
 172     local ssl_lib
 173
 174     # check 'enabled' option
 175     #
 176     if [ ${adb_enabled} -ne 1 ]
 177     then
 178         if [ -s "${adb_dnsdir}/${adb_dnsfile}" ]
 179         then
 180             f_rmdns
 181             f_dnsrestart
 182         fi
 183         f_log "info " "adblock is currently disabled, please set adb_enabled to '1' to use this service"
 184         exit 0
 185     fi
 186
 187     # check fetch utility
 188     #
 189     ssl_lib="-"
 190     if [ -x "${adb_fetch}" ]
 191     then
 192         if [ "$(readlink -fn "${adb_fetch}")" = "/usr/bin/wget-nossl" ]
 193         then
 194             adb_fetchparm="--quiet --no-cache --no-cookies --max-redirect=0 --timeout=10 -O"
 195         elif [ "$(readlink -fn "/bin/wget")" = "/bin/busybox" ] || [ "$(readlink -fn "${adb_fetch}")" = "/bin/busybox" ]
 196         then
 197             adb_fetch="/bin/busybox"
 198             adb_fetchparm="-q -O"
 199         else
 200             ssl_lib="built-in"
 201         fi
 202     fi
 203     if [ ! -x "${adb_fetch}" ] && [ "$(readlink -fn "/bin/wget")" = "/bin/uclient-fetch" ]
 204     then
 205         adb_fetch="/bin/uclient-fetch"
 206         if [ -f "/lib/libustream-ssl.so" ]
 207         then
 208             adb_fetchparm="-q --timeout=10 --no-check-certificate -O"
 209             ssl_lib="libustream-ssl"
 210         else
 211             adb_fetchparm="-q --timeout=10 -O"
 212         fi
 213     fi
 214     if [ ! -x "${adb_fetch}" ] || [ -z "${adb_fetch}" ] || [ -z "${adb_fetchparm}" ]
 215     then
 216         f_log "error" "no download utility found, please install 'uclient-fetch' with 'libustream-mbedtls' or the full 'wget' package"
 217     fi
 218     adb_fetchinfo="${adb_fetch##*/} (${ssl_lib})"
 219
 220     # create dns hideout directory
 221     #
 222     if [ ! -d "${adb_dnshidedir}" ]
 223     then
 224         mkdir -p -m 660 "${adb_dnshidedir}"
 225         chown -R "${adb_dns}":"${adb_dns}" "${adb_dnshidedir}" 2>/dev/null
 226     else
 227         rm -f "${adb_dnshidedir}/${adb_dnsprefix}"*
 228     fi
 229
 230     # create adblock temp file/directory
 231     #
 232     adb_tmpload="$(mktemp -tu)"
 233     adb_tmpfile="$(mktemp -tu)"
 234     adb_tmpdir="$(mktemp -p /tmp -d)"
 235
 236     # prepare whitelist entries
 237     #
 238     if [ -s "${adb_whitelist}" ]
 239     then
 240         awk "${adb_whitelist_rset}" "${adb_whitelist}" > "${adb_tmpdir}/tmp.whitelist"
 241     fi
 242 }
 243
 244 # f_rmtemp: remove temporary files & directories
 245 #
 246 f_rmtemp()
 247 {
 248     if [ -d "${adb_tmpdir}" ]
 249     then
 250         rm -f "${adb_tmpload}"
 251         rm -f "${adb_tmpfile}"
 252         rm -rf "${adb_tmpdir}"
 253     fi
 254 }
 255
 256 # f_rmdns: remove dns related files & directories
 257 #
 258 f_rmdns()
 259 {
 260     if [ -n "${adb_dns}" ]
 261     then
 262         rm -f "${adb_dnsdir}/${adb_dnsprefix}"*
 263         rm -f "${adb_backupdir}/${adb_dnsprefix}"*.gz
 264         rm -rf "${adb_dnshidedir}"
 265         > "${adb_rtfile}"
 266     fi
 267 }
 268
 269 # f_dnsrestart: restart the dns backend
 270 #
 271 f_dnsrestart()
 272 {
 273     local dns_up mem_free cnt=0
 274
 275     "/etc/init.d/${adb_dns}" restart >/dev/null 2>&1
 276     while [ ${cnt} -le 10 ]
 277     do
 278         dns_up="$(ubus -S call service list "{\"name\":\"${adb_dns}\"}" | jsonfilter -l1 -e "@.${adb_dns}.instances.*.running")"
 279         if [ "${dns_up}" = "true" ]
 280         then
 281             mem_free="$(awk '/^MemFree/ {print int($2/1000)}' "/proc/meminfo")"
 282             if [ ${mem_free} -ge ${adb_minfree} ]
 283             then
 284                 return 0
 285             fi
 286         fi
 287         cnt=$((cnt+1))
 288         sleep 1
 289     done
 290     return 1
 291 }
 292
 293 # f_list: backup/restore/remove block lists
 294 #
 295 f_list()
 296 {
 297     local mode="${1}" in_rc="${adb_rc}" cnt=0
 298
 299     case "${mode}" in
 300         backup)
 301             cnt="$(wc -l < "${adb_tmpfile}")"
 302             if [ ${adb_backup} -eq 1 ] && [ -d "${adb_backupdir}" ]
 303             then
 304                 gzip -cf "${adb_tmpfile}" > "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz"
 305                 adb_rc=${?}
 306             fi
 307             ;;
 308         restore)
 309             if [ ${adb_backup} -eq 1 ] && [ -d "${adb_backupdir}" ] &&
 310                 [ -f "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz" ]
 311             then
 312                 gunzip -cf "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz" > "${adb_tmpfile}"
 313                 adb_rc=${?}
 314             fi
 315             ;;
 316         remove)
 317             if [ -d "${adb_backupdir}" ]
 318             then
 319                 rm -f "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz"
 320             fi
 321             adb_rc=${?}
 322             ;;
 323         merge)
 324             if [ -s "${adb_tmpfile}" ]
 325             then
 326                 cat "${adb_tmpfile}" >> "${adb_tmpdir}/${adb_dnsfile}"
 327                 adb_rc=${?}
 328             fi
 329             ;;
 330         format)
 331             if [ -s "${adb_tmpdir}/tmp.whitelist" ]
 332             then
 333                 grep -vf "${adb_tmpdir}/tmp.whitelist" "${adb_tmpdir}/${adb_dnsfile}" | eval "${adb_dnsformat}" > "${adb_dnsdir}/${adb_dnsfile}"
 334             else
 335                 eval "${adb_dnsformat}" "${adb_tmpdir}/${adb_dnsfile}" > "${adb_dnsdir}/${adb_dnsfile}"
 336             fi
 337             adb_rc=${?}
 338             ;;
 339     esac
 340     f_log "debug" "name: ${src_name}, mode: ${mode}, count: ${cnt}, in_rc: ${in_rc}, out_rc: ${adb_rc}"
 341 }
 342
 343 # f_tldcompression: top level domain compression
 344 #
 345 f_tldcompression()
 346 {
 347     local source="${1}" temp="${adb_tmpload}"
 348
 349     awk -F "." '{for(f=NF;f > 1;f--) printf "%s.", $f;print $1}' "${source}" 2>/dev/null | sort -u > "${temp}"
 350     awk '{if(NR==1){tld=$NF};while(getline){if($NF !~ tld"\\."){print tld;tld=$NF}}print tld}' "${temp}" 2>/dev/null > "${source}"
 351     awk -F "." '{for(f=NF;f > 1;f--) printf "%s.", $f;print $1}' "${source}" 2>/dev/null > "${temp}"
 352     sort -u "${temp}" > "${source}"
 353 }
 354
 355 # f_switch: suspend/resume adblock processing
 356 #
 357 f_switch()
 358 {
 359     local source target status mode="${1}"
 360
 361     if [ -d "${adb_dnshidedir}" ]
 362     then
 363         if [ -s "${adb_dnsdir}/${adb_dnsfile}" ] && [ "${mode}" = "suspend" ]
 364         then
 365             source="${adb_dnsdir}/${adb_dnsfile}"
 366             target="${adb_dnshidedir}"
 367             status="suspended"
 368         elif [ -s "${adb_dnshidedir}/${adb_dnsfile}" ] && [ "${mode}" = "resume" ]
 369         then
 370             source="${adb_dnshidedir}/${adb_dnsfile}"
 371             target="${adb_dnsdir}"
 372             status="resumed"
 373         fi
 374         if [ -n "${status}" ]
 375         then
 376             mv -f "${source}"* "${target}"
 377             f_dnsrestart
 378             f_log "info " "adblock processing ${status}"
 379         fi
 380     fi
 381 }
 382
 383 # f_query: query block list for certain (sub-)domains
 384 #
 385 f_query()
 386 {
 387     local search result cnt
 388     local domain="${1}"
 389     local tld="${domain#*.}"
 390
 391     if [ ! -s "${adb_dnsdir}/${adb_dnsfile}" ]
 392     then
 393          printf "%s\n" "::: no active block list found, please start / resume adblock first"
 394     elif [ -z "${domain}" ] || [ "${domain}" = "${tld}" ]
 395     then
 396         printf "%s\n" "::: invalid domain input, please submit a specific (sub-)domain, e.g. 'www.abc.xyz'"
 397     else
 398         cd "${adb_dnsdir}"
 399         while [ "${domain}" != "${tld}" ]
 400         do
 401             search="${domain//./\.}"
 402             result="$(grep -Hm5 "[/\"\.]${search}[/\"]" "${adb_dnsfile}" | awk -F ':|=|/|\"' '{printf("  + %s\n",$4)}')"
 403             printf "%s\n" "::: results for (sub-)domain '${domain}' (max. 5)"
 404             printf "%s\n" "${result:="  - no match"}"
 405             domain="${tld}"
 406             tld="${domain#*.}"
 407         done
 408     fi
 409 }
 410
 411 # f_status: output runtime information
 412 #
 413 f_status()
 414 {
 415     local key keylist value
 416
 417     if [ -s "${adb_rtfile}" ]
 418     then
 419         if [ -s "${adb_dnsdir}/${adb_dnsfile}" ]
 420         then
 421             value="active"
 422         else
 423             value="no domains blocked"
 424         fi
 425         printf "%s\n" "::: adblock runtime information"
 426         printf " %-15s : %s\n" "status" "${value}"
 427         json_load "$(cat "${adb_rtfile}" 2>/dev/null)"
 428         json_select data
 429         json_get_keys keylist
 430         for key in ${keylist}
 431         do
 432             json_get_var value "${key}"
 433             printf " %-15s : %s\n" "${key}" "${value}"
 434         done
 435     fi
 436 }
 437
 438 # f_log: write to syslog, exit on error
 439 #
 440 f_log()
 441 {
 442     local class="${1}" log_msg="${2}"
 443
 444     if [ -n "${log_msg}" ] && ([ "${class}" != "debug" ] || [ ${adb_debug} -eq 1 ])
 445     then
 446         logger -t "adblock-[${adb_ver}] ${class}" "${log_msg}"
 447         if [ "${class}" = "error" ]
 448         then
 449             logger -t "adblock-[${adb_ver}] ${class}" "Please check 'https://github.com/openwrt/packages/blob/master/net/adblock/files/README.md' (${adb_sysver})"
 450             f_rmtemp
 451             if [ -s "${adb_dnsdir}/${adb_dnsfile}" ]
 452             then
 453                 f_rmdns
 454                 f_dnsrestart
 455             fi
 456             exit 1
 457         fi
 458     fi
 459 }
 460
 461 # main function for block list processing
 462 #
 463 f_main()
 464 {
 465     local src_name src_rset shalla_archive enabled url hash_old hash_new cnt=0
 466     local mem_total="$(awk '/^MemTotal/ {print int($2/1000)}' "/proc/meminfo")"
 467
 468     f_log "info " "start adblock processing ..."
 469     f_log "debug" "action: ${adb_action}, manual_mode:${adb_manmode}, backup: ${adb_backup}, dns: ${adb_dns}, fetch: ${adb_fetchinfo}, mem_total: ${mem_total}, force_srt/_dns: ${adb_forcesrt}/${adb_forcedns}"
 470     > "${adb_rtfile}"
 471     for src_name in ${adb_sources}
 472     do
 473         eval "enabled=\"\${enabled_${src_name}}\""
 474         eval "url=\"\${adb_src_${src_name}}\""
 475         eval "src_rset=\"\${adb_src_rset_${src_name}}\""
 476         > "${adb_tmpload}"
 477         > "${adb_tmpfile}"
 478         adb_rc=4
 479
 480         # basic pre-checks
 481         #
 482         f_log "debug" "name: ${src_name}, enabled: ${enabled}, url: ${url}, rset: ${src_rset}"
 483         if [ "${enabled}" != "1" ] || [ -z "${url}" ] || [ -z "${src_rset}" ]
 484         then
 485             f_list remove
 486             continue
 487         fi
 488
 489         # manual / backup mode
 490         #
 491         if [ ${adb_manmode} -eq 1 ] && [ -z "${adb_action}" ] && [ "${src_name}" != "blacklist" ]
 492         then
 493             f_list restore
 494             if [ ${adb_rc} -eq 0 ] && [ -s "${adb_tmpfile}" ]
 495             then
 496                 f_list merge
 497                 continue
 498             fi
 499         fi
 500
 501         # download block list
 502         #
 503         if [ "${src_name}" = "blacklist" ] && [ -s "${url}" ]
 504         then
 505             cat "${url}" > "${adb_tmpload}"
 506             adb_rc=${?}
 507         elif [ "${src_name}" = "shalla" ]
 508         then
 509             shalla_archive="${adb_tmpdir}/shallalist.tar.gz"
 510             "${adb_fetch}" ${adb_fetchparm} "${shalla_archive}" "${url}" 2>/dev/null
 511             adb_rc=${?}
 512             if [ ${adb_rc} -eq 0 ]
 513             then
 514                 for category in ${adb_src_cat_shalla}
 515                 do
 516                     tar -xOzf "${shalla_archive}" "BL/${category}/domains" >> "${adb_tmpload}"
 517                     adb_rc=${?}
 518                     if [ ${adb_rc} -ne 0 ]
 519                     then
 520                         break
 521                     fi
 522                 done
 523             fi
 524             rm -f "${shalla_archive}"
 525             rm -rf "${adb_tmpdir}/BL"
 526         else
 527             "${adb_fetch}" ${adb_fetchparm} "${adb_tmpload}" "${url}" 2>/dev/null
 528             adb_rc=${?}
 529         fi
 530
 531         # check download result and prepare list output (incl. tld compression, list backup & restore)
 532         #
 533         if [ ${adb_rc} -eq 0 ] && [ -s "${adb_tmpload}" ]
 534         then
 535             awk "${src_rset}" "${adb_tmpload}" 2>/dev/null > "${adb_tmpfile}"
 536             if [ -s "${adb_tmpfile}" ]
 537             then
 538                 f_tldcompression "${adb_tmpfile}"
 539                 f_list backup
 540             else
 541                 f_list restore
 542             fi
 543         else
 544             f_list restore
 545         fi
 546
 547         # list merge
 548         #
 549         if [ ${adb_rc} -eq 0 ] && [ -s "${adb_tmpfile}" ]
 550         then
 551             f_list merge
 552             if [ ${adb_rc} -ne 0 ]
 553             then
 554                 f_list remove
 555             fi
 556         else
 557             f_list remove
 558         fi
 559     done
 560
 561     # hash preparation, whitelist removal and overall sort
 562     #
 563     if [ -f "${adb_dnsdir}/${adb_dnsfile}" ]
 564     then
 565         hash_old="$(sha256sum "${adb_dnsdir}/${adb_dnsfile}" | awk '{print $1}')"
 566     fi
 567     if [ -s "${adb_tmpdir}/${adb_dnsfile}" ]
 568     then
 569         if [ ${mem_total} -ge 64 ] || [ ${adb_forcesrt} -eq 1 ]
 570         then
 571             f_tldcompression "${adb_tmpdir}/${adb_dnsfile}"
 572         fi
 573         f_list format
 574     else
 575         > "${adb_dnsdir}/${adb_dnsfile}"
 576     fi
 577     hash_new="$(sha256sum "${adb_dnsdir}/${adb_dnsfile}" | awk '{print $1}')"
 578     cnt="$(wc -l < "${adb_dnsdir}/${adb_dnsfile}")"
 579
 580     # conditional restart of the dns backend and runtime information export
 581     #
 582     chown "${adb_dns}":"${adb_dns}" "${adb_dnsdir}/${adb_dnsfile}" 2>/dev/null
 583     f_rmtemp
 584     if [ "${hash_old}" != "${hash_new}" ]
 585     then
 586         f_dnsrestart
 587     fi
 588     if [ ${?} -eq 0 ]
 589     then
 590         json_init
 591         json_add_object "data"
 592         json_add_string "adblock_version" "${adb_ver}"
 593         json_add_string "blocked_domains" "${cnt}"
 594         json_add_string "fetch_info" "${adb_fetchinfo}"
 595         json_add_string "dns_backend" "${adb_dns}"
 596         json_add_string "last_rundate" "$(/bin/date "+%d.%m.%Y %H:%M:%S")"
 597         json_add_string "system" "${adb_sysver}"
 598         json_close_object
 599         json_dump > "${adb_rtfile}"
 600         f_log "info " "block list with overall ${cnt} domains loaded successfully (${adb_sysver})"
 601     else
 602         f_log "error" "dns backend restart with active block list failed"
 603     fi
 604 }
 605
 606 # handle different adblock actions
 607 #
 608 f_envload
 609 case "${adb_action}" in
 610     stop)
 611         f_rmtemp
 612         f_rmdns
 613         f_dnsrestart
 614         ;;
 615     restart)
 616         f_rmtemp
 617         f_rmdns
 618         f_envcheck
 619         f_main
 620         ;;
 621     suspend)
 622         f_switch suspend
 623         ;;
 624     resume)
 625         f_switch resume
 626         ;;
 627     query)
 628         f_query "${2}"
 629         ;;
 630     status)
 631         f_status
 632         ;;
 633     *)
 634         f_envcheck
 635         f_main
 636         ;;
 637 esac
 638 exit 0