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="3.0.0"
  14 adb_sysver="$(ubus -S call system board | jsonfilter -e '@.release.description')"
  15 adb_enabled=0
  16 adb_debug=0
  17 adb_manmode=0
  18 adb_forcesrt=0
  19 adb_forcedns=0
  20 adb_triggerdelay=0
  21 adb_backup=0
  22 adb_backupdir="/mnt"
  23 adb_fetch="/usr/bin/wget"
  24 adb_fetchparm="--quiet --no-cache --no-cookies --max-redirect=0 --timeout=10 --no-check-certificate -O"
  25 adb_dns="dnsmasq"
  26 adb_dnsprefix="adb_list"
  27 adb_dnsfile="${adb_dnsprefix}.overall"
  28 adb_rtfile="/tmp/adb_runtime.json"
  29 adb_action="${1:-"start"}"
  30 adb_cnt=0
  31 adb_rc=0
  32
  33 # f_envload: load adblock environment
  34 #
  35 f_envload()
  36 {
  37     local dns_up cnt=0
  38
  39     # source in system libraries
  40     #
  41     if [ -r "/lib/functions.sh" ] && [ -r "/usr/share/libubox/jshn.sh" ]
  42     then
  43         . "/lib/functions.sh"
  44         . "/usr/share/libubox/jshn.sh"
  45     else
  46         f_log "error" "system libraries not found"
  47     fi
  48
  49     # parse global section by callback
  50     #
  51     config_cb()
  52     {
  53         local type="${1}"
  54         if [ "${type}" = "adblock" ]
  55         then
  56             option_cb()
  57             {
  58                 local option="${1}"
  59                 local value="${2}"
  60                 eval "${option}=\"${value}\""
  61             }
  62         else
  63             reset_cb
  64         fi
  65     }
  66
  67     # parse 'source' sections
  68     #
  69     parse_config()
  70     {
  71         local value opt section="${1}" options="enabled adb_src adb_src_rset adb_src_cat"
  72         eval "adb_sources=\"${adb_sources} ${section}\""
  73         for opt in ${options}
  74         do
  75             config_get value "${section}" "${opt}"
  76             if [ -n "${value}" ]
  77             then
  78                 eval "${opt}_${section}=\"${value}\""
  79             fi
  80         done
  81     }
  82
  83     # load adblock config
  84     #
  85     config_load adblock
  86     config_foreach parse_config source
  87
  88     # set dns backend environment
  89     #
  90     case "${adb_action}" in
  91         start|restart|reload)
  92             > "${adb_rtfile}"
  93             if [ "${adb_action}" = "start" ] && [ "${adb_trigger}" = "timed" ]
  94             then
  95                 sleep ${adb_triggerdelay}
  96             fi
  97         ;;
  98     esac
  99     while [ ${cnt} -le 30 ]
 100     do
 101         dns_up="$(ubus -S call service list "{\"name\":\"${adb_dns}\"}" 2>/dev/null | jsonfilter -l1 -e "@[\"${adb_dns}\"].instances.*.running" 2>/dev/null)"
 102         if [ "${dns_up}" = "true" ]
 103         then
 104             case "${adb_dns}" in
 105                 dnsmasq)
 106                     adb_dnsuser="${adb_dns}"
 107                     adb_dnsdir="${adb_dnsdir:-"/tmp/dnsmasq.d"}"
 108                     adb_dnsformat="awk '{print \"local=/\"\$0\"/\"}'"
 109                     break
 110                     ;;
 111                 unbound)
 112                     adb_dnsuser="${adb_dns}"
 113                     adb_dnsdir="${adb_dnsdir:-"/var/lib/unbound"}"
 114                     adb_dnsformat="awk '{print \"local-zone: \042\"\$0\"\042 static\"}'"
 115                     break
 116                     ;;
 117                 named)
 118                     adb_dnsuser="bind"
 119                     adb_dnsdir="${adb_dnsdir:-"/var/lib/bind"}"
 120                     adb_dnsformat="awk '{print \"\"\$0\" IN CNAME .\n*.\"\$0\" IN CNAME .\"}'"
 121                     break
 122                     ;;
 123                 kresd)
 124                     adb_dnsuser="root"
 125                     adb_dnsdir="${adb_dnsdir:-"/etc/kresd"}"
 126                     adb_dnsformat="awk '{print \"\"\$0\" CNAME .\n*.\"\$0\" CNAME .\"}'"
 127                     adb_dnsheader="\$TTL 2h"$'\n'"@ IN SOA localhost. root.localhost. (2 6h 1h 1w 2h)"$'\n'"  IN NS  localhost."
 128                     break
 129                     ;;
 130                 dnscrypt-proxy)
 131                     adb_dnsuser="nobody"
 132                     adb_dnsdir="${adb_dnsdir:-"/tmp"}"
 133                     adb_dnsformat="awk '{print \$0}'"
 134                     break
 135                     ;;
 136             esac
 137         fi
 138         sleep 1
 139         cnt=$((cnt+1))
 140     done
 141     if [ -z "${adb_dns}" ] || [ -z "${adb_dnsformat}" ] || [ ! -x "$(command -v ${adb_dns})" ] || [ ! -d "${adb_dnsdir}" ]
 142     then
 143         f_log "error" "'${adb_dns}' not running, DNS backend not found"
 144     fi
 145
 146     # force dns to local resolver
 147     #
 148     if [ ${adb_forcedns} -eq 1 ] && [ -z "$(uci -q get firewall.adblock_dns)" ]
 149     then
 150         uci -q set firewall.adblock_dns="redirect"
 151         uci -q set firewall.adblock_dns.name="Adblock DNS"
 152         uci -q set firewall.adblock_dns.src="lan"
 153         uci -q set firewall.adblock_dns.proto="tcp udp"
 154         uci -q set firewall.adblock_dns.src_dport="53"
 155         uci -q set firewall.adblock_dns.dest_port="53"
 156         uci -q set firewall.adblock_dns.target="DNAT"
 157     elif [ ${adb_forcedns} -eq 0 ] && [ -n "$(uci -q get firewall.adblock_dns)" ]
 158     then
 159         uci -q delete firewall.adblock_dns
 160     fi
 161     if [ -n "$(uci -q changes firewall)" ]
 162     then
 163         uci -q commit firewall
 164         if [ $(/etc/init.d/firewall enabled; printf "%u" ${?}) -eq 0 ]
 165         then
 166             /etc/init.d/firewall reload >/dev/null 2>&1
 167         fi
 168     fi
 169 }
 170
 171 # f_envcheck: check/set environment prerequisites
 172 #
 173 f_envcheck()
 174 {
 175     local ssl_lib
 176
 177     # check 'enabled' option
 178     #
 179     if [ ${adb_enabled} -ne 1 ]
 180     then
 181         if [ -s "${adb_dnsdir}/${adb_dnsfile}" ]
 182         then
 183             f_rmdns
 184             f_dnsrestart
 185         fi
 186         f_jsnupdate
 187         f_log "info " "adblock is currently disabled, please set adb_enabled to '1' to use this service"
 188         exit 0
 189     fi
 190
 191     # check fetch utility
 192     #
 193     ssl_lib="-"
 194     if [ -x "${adb_fetch}" ]
 195     then
 196         if [ "$(readlink -fn "${adb_fetch}")" = "/usr/bin/wget-nossl" ]
 197         then
 198             adb_fetchparm="--quiet --no-cache --no-cookies --max-redirect=0 --timeout=10 -O"
 199         elif [ "$(readlink -fn "${adb_fetch}")" = "/bin/busybox" ] ||
 200             ([ "$(readlink -fn "/bin/wget")" = "/bin/busybox" ] && [ "$(readlink -fn "${adb_fetch}")" != "/usr/bin/wget" ])
 201         then
 202             adb_fetch="/bin/busybox"
 203             adb_fetchparm="-q -O"
 204         else
 205             ssl_lib="built-in"
 206         fi
 207     fi
 208     if [ ! -x "${adb_fetch}" ] && [ "$(readlink -fn "/bin/wget")" = "/bin/uclient-fetch" ]
 209     then
 210         adb_fetch="/bin/uclient-fetch"
 211         if [ -f "/lib/libustream-ssl.so" ]
 212         then
 213             adb_fetchparm="-q --timeout=10 --no-check-certificate -O"
 214             ssl_lib="libustream-ssl"
 215         else
 216             adb_fetchparm="-q --timeout=10 -O"
 217         fi
 218     fi
 219     if [ ! -x "${adb_fetch}" ] || [ -z "${adb_fetch}" ] || [ -z "${adb_fetchparm}" ]
 220     then
 221         f_log "error" "no download utility found, please install 'uclient-fetch' with 'libustream-mbedtls' or the full 'wget' package"
 222     fi
 223     adb_fetchinfo="${adb_fetch##*/} (${ssl_lib})"
 224
 225     # create adblock temp file/directory
 226     #
 227     adb_tmpload="$(mktemp -tu)"
 228     adb_tmpfile="$(mktemp -tu)"
 229     adb_tmpdir="$(mktemp -p /tmp -d)"
 230
 231     # prepare whitelist entries
 232     #
 233     if [ -s "${adb_whitelist}" ] && [ -n "${adb_whitelist_rset}" ]
 234     then
 235         awk "${adb_whitelist_rset}" "${adb_whitelist}" > "${adb_tmpdir}/tmp.whitelist"
 236     fi
 237 }
 238
 239 # f_rmtemp: remove temporary files & directories
 240 #
 241 f_rmtemp()
 242 {
 243     if [ -d "${adb_tmpdir}" ]
 244     then
 245         rm -f "${adb_tmpload}"
 246         rm -f "${adb_tmpfile}"
 247         rm -rf "${adb_tmpdir}"
 248     fi
 249 }
 250
 251 # f_rmdns: remove dns related files & directories
 252 #
 253 f_rmdns()
 254 {
 255     if [ -n "${adb_dns}" ]
 256     then
 257         > "${adb_dnsdir}/${adb_dnsfile}"
 258         > "${adb_rtfile}"
 259         rm -f "${adb_dnsdir}/.${adb_dnsfile}"
 260         rm -f "${adb_backupdir}/${adb_dnsprefix}"*.gz
 261     fi
 262 }
 263
 264 # f_dnsrestart: restart the dns backend
 265 #
 266 f_dnsrestart()
 267 {
 268     local dns_up cnt=0
 269
 270     "/etc/init.d/${adb_dns}" restart >/dev/null 2>&1
 271     while [ ${cnt} -le 10 ]
 272     do
 273         dns_up="$(ubus -S call service list "{\"name\":\"${adb_dns}\"}" | jsonfilter -l1 -e "@[\"${adb_dns}\"].instances.*.running")"
 274         if [ "${dns_up}" = "true" ]
 275         then
 276             return 0
 277         fi
 278         cnt=$((cnt+1))
 279         sleep 1
 280     done
 281     return 1
 282 }
 283
 284 # f_list: backup/restore/remove block lists
 285 #
 286 f_list()
 287 {
 288     local mode="${1}" in_rc="${adb_rc}" cnt=0
 289
 290     case "${mode}" in
 291         backup)
 292             cnt="$(wc -l < "${adb_tmpfile}")"
 293             if [ ${adb_backup} -eq 1 ] && [ -d "${adb_backupdir}" ]
 294             then
 295                 gzip -cf "${adb_tmpfile}" > "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz"
 296                 adb_rc=${?}
 297             fi
 298             ;;
 299         restore)
 300             if [ ${adb_backup} -eq 1 ] && [ -d "${adb_backupdir}" ] &&
 301                 [ -f "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz" ]
 302             then
 303                 gunzip -cf "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz" > "${adb_tmpfile}"
 304                 adb_rc=${?}
 305             fi
 306             ;;
 307         remove)
 308             if [ -d "${adb_backupdir}" ]
 309             then
 310                 rm -f "${adb_backupdir}/${adb_dnsprefix}.${src_name}.gz"
 311             fi
 312             adb_rc=${?}
 313             ;;
 314         merge)
 315             if [ -s "${adb_tmpfile}" ]
 316             then
 317                 cat "${adb_tmpfile}" >> "${adb_tmpdir}/${adb_dnsfile}"
 318                 adb_rc=${?}
 319             fi
 320             ;;
 321         format)
 322             if [ -s "${adb_tmpdir}/tmp.whitelist" ]
 323             then
 324                 grep -vf "${adb_tmpdir}/tmp.whitelist" "${adb_tmpdir}/${adb_dnsfile}" | eval "${adb_dnsformat}" > "${adb_dnsdir}/${adb_dnsfile}"
 325             else
 326                 eval "${adb_dnsformat}" "${adb_tmpdir}/${adb_dnsfile}" > "${adb_dnsdir}/${adb_dnsfile}"
 327             fi
 328             if [ -n "${adb_dnsheader}" ]
 329             then
 330                 printf '%s\n' "${adb_dnsheader}" | cat - "${adb_dnsdir}/${adb_dnsfile}" > "${adb_tmpdir}/${adb_dnsfile}"
 331                 cat "${adb_tmpdir}/${adb_dnsfile}" > "${adb_dnsdir}/${adb_dnsfile}"
 332             fi
 333             adb_rc=${?}
 334             ;;
 335     esac
 336     f_log "debug" "name: ${src_name}, mode: ${mode}, count: ${cnt}, in_rc: ${in_rc}, out_rc: ${adb_rc}"
 337 }
 338
 339 # f_tldcompression: top level domain compression
 340 #
 341 f_tldcompression()
 342 {
 343     local source="${1}" temp="${adb_tmpload}"
 344
 345     awk -F "." '{for(f=NF;f > 1;f--) printf "%s.", $f;print $1}' "${source}" 2>/dev/null | sort -u > "${temp}"
 346     awk '{if(NR==1){tld=$NF};while(getline){if($NF !~ tld"\\."){print tld;tld=$NF}}print tld}' "${temp}" 2>/dev/null > "${source}"
 347     awk -F "." '{for(f=NF;f > 1;f--) printf "%s.", $f;print $1}' "${source}" 2>/dev/null > "${temp}"
 348     sort -u "${temp}" > "${source}"
 349 }
 350
 351 # f_switch: suspend/resume adblock processing
 352 #
 353 f_switch()
 354 {
 355     local source target status mode="${1}"
 356
 357     if [ -s "${adb_dnsdir}/${adb_dnsfile}" ] && [ "${mode}" = "suspend" ]
 358     then
 359         source="${adb_dnsdir}/${adb_dnsfile}"
 360         target="${adb_dnsdir}/.${adb_dnsfile}"
 361         status="suspended"
 362     elif [ -s "${adb_dnsdir}/.${adb_dnsfile}" ] && [ "${mode}" = "resume" ]
 363     then
 364         source="${adb_dnsdir}/.${adb_dnsfile}"
 365         target="${adb_dnsdir}/${adb_dnsfile}"
 366         status="resumed"
 367     fi
 368     if [ -n "${status}" ]
 369     then
 370         cat "${source}" > "${target}"
 371         > "${source}"
 372         f_dnsrestart
 373         f_jsnupdate
 374         f_log "info " "adblock processing ${status}"
 375     fi
 376 }
 377
 378 # f_query: query block list for certain (sub-)domains
 379 #
 380 f_query()
 381 {
 382     local search result cnt
 383     local domain="${1}"
 384     local tld="${domain#*.}"
 385
 386     if [ ! -s "${adb_dnsdir}/${adb_dnsfile}" ]
 387     then
 388          printf "%s\n" "::: no active block list found, please start / resume adblock first"
 389     elif [ -z "${domain}" ] || [ "${domain}" = "${tld}" ]
 390     then
 391         printf "%s\n" "::: invalid domain input, please submit a single domain, e.g. 'doubleclick.net'"
 392     else
 393         cd "${adb_dnsdir}"
 394         while [ "${domain}" != "${tld}" ]
 395         do
 396             search="${domain//./\.}"
 397             if [ "${adb_dns}" = "dnsmasq" ] || [ "${adb_dns}" = "unbound" ]
 398             then
 399                 result="$(awk -F '/|\"' "/[\/\"\.]${search}/{i++;{printf(\"  + %s\n\",\$2)};if(i>9){exit}}" "${adb_dnsfile}")"
 400             else
 401                 result="$(awk "/(^[^\*][a-z]*[\.]+${search}|^${search})/{i++;{printf(\"  + %s\n\",\$1)};if(i>9){exit}}" "${adb_dnsfile}")"
 402             fi
 403             printf "%s\n" "::: max. ten results for domain '${domain}'"
 404             printf "%s\n" "${result:-"  - no match"}"
 405             domain="${tld}"
 406             tld="${domain#*.}"
 407         done
 408     fi
 409 }
 410
 411 # f_jsnupdate: update runtime information
 412 #
 413 f_jsnupdate()
 414 {
 415     local status rundate="$(/bin/date "+%d.%m.%Y %H:%M:%S")"
 416
 417     if [ ${adb_rc} -gt 0 ]
 418     then
 419         status="error"
 420     elif [ ${adb_enabled} -ne 1 ]
 421     then
 422         status="disabled"
 423     elif [ -s "${adb_dnsdir}/.${adb_dnsfile}" ]
 424     then
 425         status="paused"
 426     else
 427         status="enabled"
 428         if [ -s "${adb_dnsdir}/${adb_dnsfile}" ]
 429         then
 430             if [ "${adb_dns}" = "named" ] || [ "${adb_dns}" = "kresd" ]
 431             then
 432                 adb_cnt="$(( ( $(wc -l < "${adb_dnsdir}/${adb_dnsfile}") - $(printf "%s" "${adb_dnsheader}" | grep -c "^") ) / 2 ))"
 433             else
 434                 adb_cnt="$(( $(wc -l < "${adb_dnsdir}/${adb_dnsfile}") - $(printf "%s" "${adb_dnsheader}" | grep -c "^") ))"
 435             fi
 436         fi
 437     fi
 438
 439     if [ -z "${adb_fetchinfo}" ] && [ -s "${adb_rtfile}" ]
 440     then
 441         json_load "$(cat "${adb_rtfile}" 2>/dev/null)"
 442         json_select data
 443         json_get_var adb_fetchinfo "fetch_utility"
 444     fi
 445
 446     json_init
 447     json_add_object "data"
 448     json_add_string "adblock_status" "${status}"
 449     json_add_string "adblock_version" "${adb_ver}"
 450     json_add_string "blocked_domains" "${adb_cnt}"
 451     json_add_string "fetch_utility" "${adb_fetchinfo}"
 452     json_add_string "dns_backend" "${adb_dns} (${adb_dnsdir})"
 453     json_add_string "last_rundate" "${rundate}"
 454     json_add_string "system_release" "${adb_sysver}"
 455     json_close_object
 456     json_dump > "${adb_rtfile}"
 457 }
 458
 459 # f_status: output runtime information
 460 #
 461 f_status()
 462 {
 463     local key keylist value
 464
 465     if [ -s "${adb_rtfile}" ]
 466     then
 467         printf "%s\n" "::: adblock runtime information"
 468         json_load "$(cat "${adb_rtfile}" 2>/dev/null)"
 469         json_select data
 470         json_get_keys keylist
 471         for key in ${keylist}
 472         do
 473             json_get_var value "${key}"
 474             printf "  + %-15s : %s\n" "${key}" "${value}"
 475         done
 476     fi
 477 }
 478
 479 # f_log: write to syslog, exit on error
 480 #
 481 f_log()
 482 {
 483     local class="${1}" log_msg="${2}"
 484
 485     if [ -n "${log_msg}" ] && ([ "${class}" != "debug" ] || [ ${adb_debug} -eq 1 ])
 486     then
 487         logger -t "adblock-[${adb_ver}] ${class}" "${log_msg}"
 488         if [ "${class}" = "error" ]
 489         then
 490             logger -t "adblock-[${adb_ver}] ${class}" "Please check 'https://github.com/openwrt/packages/blob/master/net/adblock/files/README.md' (${adb_sysver})"
 491             f_rmtemp
 492             if [ -s "${adb_dnsdir}/${adb_dnsfile}" ]
 493             then
 494                 f_rmdns
 495                 f_dnsrestart
 496             fi
 497             adb_rc=1
 498             f_jsnupdate
 499             exit 1
 500         fi
 501     fi
 502 }
 503
 504 # main function for block list processing
 505 #
 506 f_main()
 507 {
 508     local src_name src_rset shalla_archive enabled url hash_old hash_new
 509     local mem_total="$(awk '/^MemTotal/ {print int($2/1000)}' "/proc/meminfo")"
 510
 511     f_log "info " "start adblock processing ..."
 512     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}"
 513     > "${adb_rtfile}"
 514     for src_name in ${adb_sources}
 515     do
 516         eval "enabled=\"\${enabled_${src_name}}\""
 517         eval "url=\"\${adb_src_${src_name}}\""
 518         eval "src_rset=\"\${adb_src_rset_${src_name}}\""
 519         > "${adb_tmpload}"
 520         > "${adb_tmpfile}"
 521         adb_rc=4
 522
 523         # basic pre-checks
 524         #
 525         f_log "debug" "name: ${src_name}, enabled: ${enabled}, url: ${url}, rset: ${src_rset}"
 526         if [ "${enabled}" != "1" ] || [ -z "${url}" ] || [ -z "${src_rset}" ]
 527         then
 528             f_list remove
 529             continue
 530         fi
 531
 532         # manual / backup mode
 533         #
 534         if [ ${adb_manmode} -eq 1 ] && [ "${adb_action}" = "start" ] && [ "${src_name}" != "blacklist" ]
 535         then
 536             f_list restore
 537             if [ ${adb_rc} -eq 0 ] && [ -s "${adb_tmpfile}" ]
 538             then
 539                 f_list merge
 540                 continue
 541             fi
 542         fi
 543
 544         # download block list
 545         #
 546         if [ "${src_name}" = "blacklist" ] && [ -s "${url}" ]
 547         then
 548             cat "${url}" > "${adb_tmpload}"
 549             adb_rc=${?}
 550         elif [ "${src_name}" = "shalla" ]
 551         then
 552             shalla_archive="${adb_tmpdir}/shallalist.tar.gz"
 553             "${adb_fetch}" ${adb_fetchparm} "${shalla_archive}" "${url}" 2>/dev/null
 554             adb_rc=${?}
 555             if [ ${adb_rc} -eq 0 ]
 556             then
 557                 for category in ${adb_src_cat_shalla}
 558                 do
 559                     tar -xOzf "${shalla_archive}" "BL/${category}/domains" >> "${adb_tmpload}"
 560                     adb_rc=${?}
 561                     if [ ${adb_rc} -ne 0 ]
 562                     then
 563                         break
 564                     fi
 565                 done
 566             fi
 567             rm -f "${shalla_archive}"
 568             rm -rf "${adb_tmpdir}/BL"
 569         else
 570             "${adb_fetch}" ${adb_fetchparm} "${adb_tmpload}" "${url}" 2>/dev/null
 571             adb_rc=${?}
 572         fi
 573
 574         # check download result and prepare list output (incl. tld compression, list backup & restore)
 575         #
 576         if [ ${adb_rc} -eq 0 ] && [ -s "${adb_tmpload}" ]
 577         then
 578             awk "${src_rset}" "${adb_tmpload}" 2>/dev/null > "${adb_tmpfile}"
 579             if [ -s "${adb_tmpfile}" ]
 580             then
 581                 f_tldcompression "${adb_tmpfile}"
 582                 if [ "${src_name}" != "blacklist" ]
 583                 then
 584                     f_list backup
 585                 fi
 586             else
 587                 f_list restore
 588             fi
 589         else
 590             f_list restore
 591         fi
 592
 593         # list merge
 594         #
 595         if [ ${adb_rc} -eq 0 ] && [ -s "${adb_tmpfile}" ]
 596         then
 597             f_list merge
 598             if [ ${adb_rc} -ne 0 ]
 599             then
 600                 f_list remove
 601             fi
 602         else
 603             f_list remove
 604         fi
 605     done
 606
 607     # hash preparation, whitelist removal and overall sort
 608     #
 609     if [ -f "${adb_dnsdir}/${adb_dnsfile}" ]
 610     then
 611         hash_old="$(sha256sum "${adb_dnsdir}/${adb_dnsfile}" 2>/dev/null | awk '{print $1}')"
 612     fi
 613     if [ -s "${adb_tmpdir}/${adb_dnsfile}" ]
 614     then
 615         if [ ${mem_total} -ge 64 ] || [ ${adb_forcesrt} -eq 1 ]
 616         then
 617             f_tldcompression "${adb_tmpdir}/${adb_dnsfile}"
 618         fi
 619         f_list format
 620     else
 621         > "${adb_dnsdir}/${adb_dnsfile}"
 622     fi
 623     chown "${adb_dnsuser}":"${adb_dnsuser}" "${adb_dnsdir}/${adb_dnsfile}" 2>/dev/null
 624     f_rmtemp
 625
 626     # conditional restart of the dns backend and runtime information export
 627     #
 628     hash_new="$(sha256sum "${adb_dnsdir}/${adb_dnsfile}" 2>/dev/null | awk '{print $1}')"
 629     if [ -z "${hash_old}" ] || [ -z "${hash_new}" ] || [ "${hash_old}" != "${hash_new}" ]
 630     then
 631         f_dnsrestart
 632     fi
 633     if [ ${?} -eq 0 ]
 634     then
 635         f_jsnupdate "${adb_cnt}"
 636         f_log "info " "block list with overall ${adb_cnt} domains loaded successfully (${adb_sysver})"
 637     else
 638         f_log "error" "dns backend restart with active block list failed"
 639     fi
 640 }
 641
 642 # handle different adblock actions
 643 #
 644 f_envload
 645 case "${adb_action}" in
 646     stop)
 647         f_rmtemp
 648         f_rmdns
 649         f_dnsrestart
 650         ;;
 651     restart)
 652         f_rmtemp
 653         f_rmdns
 654         f_envcheck
 655         f_main
 656         ;;
 657     suspend)
 658         f_switch suspend
 659         ;;
 660     resume)
 661         f_switch resume
 662         ;;
 663     query)
 664         f_query "${2}"
 665         ;;
 666     status)
 667         f_status
 668         ;;
 669     *)
 670         f_envcheck
 671         f_main
 672         ;;
 673 esac
 674 exit 0