src/initscripts/system/unbound

   1 #!/bin/sh
   2 # Begin $rc_base/init.d/unbound
   3
   4 # Description : Unbound DNS resolver boot script for IPfire
   5 # Author      : Marcel Lorenz <marcel.lorenz@ipfire.org>
   6
   7 . /etc/sysconfig/rc
   8 . ${rc_functions}
   9
  10 TEST_DOMAIN="ipfire.org"
  11
  12 # This domain will never validate
  13 TEST_DOMAIN_FAIL="dnssec-failed.org"
  14
  15 INSECURE_ZONES=
  16 USE_FORWARDERS=1
  17
  18 # Cache any local zones for 60 seconds
  19 LOCAL_TTL=60
  20
  21 # EDNS buffer size
  22 EDNS_DEFAULT_BUFFER_SIZE=4096
  23
  24 # Load optional configuration
  25 [ -e "/etc/sysconfig/unbound" ] && . /etc/sysconfig/unbound
  26
  27 function cidr() {
  28     local cidr nbits IFS;
  29     IFS=. read -r i1 i2 i3 i4 <<< ${1}
  30     IFS=. read -r m1 m2 m3 m4 <<< ${2}
  31     cidr=$(printf "%d.%d.%d.%d\n" "$((i1 & m1))" "$((i2 & m2))" "$((i3 & m3))" "$((i4 & m4))")
  32     nbits=0
  33     IFS=.
  34     for dec in $2 ; do
  35         case $dec in
  36             255) let nbits+=8;;
  37             254) let nbits+=7;;
  38             252) let nbits+=6;;
  39             248) let nbits+=5;;
  40             240) let nbits+=4;;
  41             224) let nbits+=3;;
  42             192) let nbits+=2;;
  43             128) let nbits+=1;;
  44             0);;
  45             *) echo "Error: $dec is not recognised"; exit 1
  46         esac
  47     done
  48     echo "${cidr}/${nbits}"
  49 }
  50
  51 ip_address_revptr() {
  52         local addr=${1}
  53
  54         local a1 a2 a3 a4
  55         IFS=. read -r a1 a2 a3 a4 <<< ${addr}
  56
  57         echo "${a4}.${a3}.${a2}.${a1}.in-addr.arpa"
  58 }
  59
  60 read_name_servers() {
  61         local i
  62         for i in 1 2; do
  63                 echo "$(</var/ipfire/red/dns${i})"
  64         done 2>/dev/null | xargs echo
  65 }
  66
  67 config_header() {
  68         echo "# This file is automatically generated and any changes"
  69         echo "# will be overwritten. DO NOT EDIT!"
  70         echo
  71 }
  72
  73 update_forwarders() {
  74         if [ "${USE_FORWARDERS}" = "1" -a -e "/var/ipfire/red/active" ]; then
  75                 local forwarders
  76                 local broken_forwarders
  77
  78                 local ns
  79                 for ns in $(read_name_servers); do
  80                         test_name_server ${ns} &>/dev/null
  81                         case "$?" in
  82                                 # Only use DNSSEC-validating or DNSSEC-aware name servers
  83                                 0|2)
  84                                         forwarders="${forwarders} ${ns}"
  85                                         ;;
  86                                 *)
  87                                         broken_forwarders="${broken_forwarders} ${ns}"
  88                                         ;;
  89                         esac
  90                 done
  91
  92                 # Determine EDNS buffer size
  93                 local new_edns_buffer_size=${EDNS_DEFAULT_BUFFER_SIZE}
  94
  95                 for ns in ${forwarders}; do
  96                         local edns_buffer_size=$(ns_determine_edns_buffer_size ${ns})
  97                         if [ -n "${edns_buffer_size}" ]; then
  98                                 if [ ${edns_buffer_size} -lt ${new_edns_buffer_size} ]; then
  99                                         new_edns_buffer_size=${edns_buffer_size}
 100                                 fi
 101                         fi
 102                 done
 103
 104                 if [ ${new_edns_buffer_size} -lt ${EDNS_DEFAULT_BUFFER_SIZE} ]; then
 105                         boot_mesg "EDNS buffer size reduced to ${new_edns_buffer_size}" ${WARNING}
 106                         echo_warning
 107
 108                         unbound-control -q set_option edns-buffer-size: ${new_edns_buffer_size}
 109                 fi
 110
 111                 # Show warning for any broken upstream name servers
 112                 if [ -n "${broken_forwarders}" ]; then
 113                         boot_mesg "Ignoring broken upstream name server(s): ${broken_forwarders:1}" ${WARNING}
 114                         echo_warning
 115                 fi
 116
 117                 if [ -n "${forwarders}" ]; then
 118                         boot_mesg "Configuring upstream name server(s): ${forwarders:1}" ${INFO}
 119                         echo_ok
 120
 121                         # Make sure DNSSEC is activated
 122                         enable_dnssec
 123
 124                         echo "${forwarders}" > /var/ipfire/red/dns
 125                         unbound-control -q forward ${forwarders}
 126                         return 0
 127
 128                 # In case we have found no working forwarders
 129                 else
 130                         # Test if the recursor mode is available
 131                         if can_resolve_root +bufsize=${new_edns_buffer_size}; then
 132                                 # Make sure DNSSEC is activated
 133                                 enable_dnssec
 134
 135                                 boot_mesg "Falling back to recursor mode" ${WARNING}
 136                                 echo_warning
 137
 138                         # If not, we set DNSSEC in permissive mode and allow using all recursors
 139                         elif [ -n "${broken_forwarders}" ]; then
 140                                 disable_dnssec
 141
 142                                 boot_mesg "DNSSEC has been set to permissive mode" ${FAILURE}
 143                                 echo_failure
 144
 145                                 echo "${broken_forwarders}" > /var/ipfire/red/dns
 146                                 unbound-control -q forward ${broken_forwarders}
 147                                 return 0
 148                         fi
 149                 fi
 150         fi
 151
 152         # If forwarders cannot be used we run in recursor mode
 153         echo "local recursor" > /var/ipfire/red/dns
 154         unbound-control -q forward off
 155 }
 156
 157 own_hostname() {
 158         local hostname=$(hostname -f)
 159         # 1.1.1.1 is reserved for unused green, skip this
 160         if [ -n "${GREEN_ADDRESS}" -a "${GREEN_ADDRESS}" != "1.1.1.1" ]; then
 161                 unbound-control -q local_data "${hostname} ${LOCAL_TTL} IN A ${GREEN_ADDRESS}"
 162         fi
 163
 164         local address
 165         for address in ${GREEN_ADDRESS} ${BLUE_ADDRESS} ${ORANGE_ADDRESS}; do
 166                 [ -n "${address}" ] || continue
 167                 [ "${address}" = "1.1.1.1" ] && continue
 168
 169                 address=$(ip_address_revptr ${address})
 170                 unbound-control -q local_data "${address} ${LOCAL_TTL} IN PTR ${hostname}"
 171         done
 172 }
 173
 174 update_hosts() {
 175         local enabled address hostname domainname
 176
 177         while IFS="," read -r enabled address hostname domainname; do
 178                 [ "${enabled}" = "on" ] || continue
 179
 180                 # Build FQDN
 181                 local fqdn="${hostname}.${domainname}"
 182
 183                 unbound-control -q local_data "${fqdn} ${LOCAL_TTL} IN A ${address}"
 184
 185                 # Skip reverse resolution if the address equals the GREEN address
 186                 [ "${address}" = "${GREEN_ADDRESS}" ] && continue
 187
 188                 # Add RDNS
 189                 address=$(ip_address_revptr ${address})
 190                 unbound-control -q local_data "${address} ${LOCAL_TTL} IN PTR ${fqdn}"
 191         done < /var/ipfire/main/hosts
 192 }
 193
 194 write_forward_conf() {
 195         (
 196                 config_header
 197
 198                 local insecure_zones="${INSECURE_ZONES}"
 199
 200                 local enabled zone server remark
 201                 while IFS="," read -r enabled zone server remark; do
 202                         # Line must be enabled.
 203                         [ "${enabled}" = "on" ] || continue
 204
 205                         # Zones that end with .local are commonly used for internal
 206                         # zones and therefore not signed
 207                         case "${zone}" in
 208                                 *.local)
 209                                         insecure_zones="${insecure_zones} ${zone}"
 210                                         ;;
 211                         esac
 212
 213                         echo "forward-zone:"
 214                         echo "  name: ${zone}"
 215                         echo "  forward-addr: ${server}"
 216                         echo
 217                 done < /var/ipfire/dnsforward/config
 218
 219                 if [ -n "${insecure_zones}" ]; then
 220                         echo "server:"
 221
 222                         for zone in ${insecure_zones}; do
 223                                 echo "  domain-insecure: ${zone}"
 224                         done
 225                 fi
 226         ) > /etc/unbound/forward.conf
 227 }
 228
 229 write_tuning_conf() {
 230         # https://www.unbound.net/documentation/howto_optimise.html
 231
 232         # Determine number of online processors
 233         local processors=$(getconf _NPROCESSORS_ONLN)
 234
 235         # Determine number of slabs
 236         local slabs=1
 237         while [ ${slabs} -lt ${processors} ]; do
 238                 slabs=$(( ${slabs} * 2 ))
 239         done
 240
 241         # Determine amount of system memory
 242         local mem=$(get_memory_amount)
 243
 244         # In the worst case scenario, unbound can use double the
 245         # amount of memory allocated to a cache due to malloc overhead
 246
 247         # Even larger systems with more than 8GB of RAM
 248         if [ ${mem} -ge 8192 ]; then
 249                 mem=1024
 250
 251         # Extra large systems with more than 4GB of RAM
 252         elif [ ${mem} -ge 4096 ]; then
 253                 mem=512
 254
 255         # Large systems with more than 2GB of RAM
 256         elif [ ${mem} -ge 2048 ]; then
 257                 mem=256
 258
 259         # Medium systems with more than 1GB of RAM
 260         elif [ ${mem} -ge 1024 ]; then
 261                 mem=128
 262
 263         # Small systems with less than 256MB of RAM
 264         elif [ ${mem} -le 256 ]; then
 265                 mem=16
 266
 267         # Everything else
 268         else
 269                 mem=64
 270         fi
 271
 272         (
 273                 config_header
 274
 275                 # We run one thread per processor
 276                 echo "num-threads: ${processors}"
 277                 echo "so-reuseport: yes"
 278
 279                 # Adjust number of slabs
 280                 echo "infra-cache-slabs: ${slabs}"
 281                 echo "key-cache-slabs: ${slabs}"
 282                 echo "msg-cache-slabs: ${slabs}"
 283                 echo "rrset-cache-slabs: ${slabs}"
 284
 285                 # Slice up the cache
 286                 echo "rrset-cache-size: $(( ${mem} / 2 ))m"
 287                 echo "msg-cache-size: $(( ${mem} / 4 ))m"
 288                 echo "key-cache-size: $(( ${mem} / 4 ))m"
 289
 290                 # Increase parallel queries
 291                 echo "outgoing-range: 8192"
 292                 echo "num-queries-per-thread: 4096"
 293
 294                 # Use larger send/receive buffers
 295                 echo "so-sndbuf: 4m"
 296                 echo "so-rcvbuf: 4m"
 297         ) > /etc/unbound/tuning.conf
 298 }
 299
 300 get_memory_amount() {
 301         local key val unit
 302
 303         while read -r key val unit; do
 304                 case "${key}" in
 305                         MemTotal:*)
 306                                 # Convert to MB
 307                                 echo "$(( ${val} / 1024 ))"
 308                                 break
 309                                 ;;
 310                 esac
 311         done < /proc/meminfo
 312 }
 313
 314 test_name_server() {
 315         local ns=${1}
 316         local args
 317
 318         # Return codes:
 319         # 0     DNSSEC validating
 320         # 1     Error: unreachable, etc.
 321         # 2     DNSSEC aware
 322         # 3     NOT DNSSEC-aware
 323
 324         # Exit when the server is not reachable
 325         ns_is_online ${ns} || return 1
 326
 327         # Determine the maximum edns buffer size that works
 328         local edns_buffer_size=$(ns_determine_edns_buffer_size ${ns})
 329         if [ -n "${edns_buffer_size}" ]; then
 330                 args="${args} +bufsize=${edns_buffer_size}"
 331         fi
 332
 333         local errors
 334         for rr in DNSKEY DS RRSIG; do
 335                 if ! ns_forwards_${rr} ${ns} ${args}; then
 336                         errors="${errors} ${rr}"
 337                 fi
 338         done
 339
 340         if [ -n "${errors}" ]; then
 341                 echo >&2 "Unable to retrieve the following resource records from ${ns}: ${errors:1}"
 342                 return 3
 343         fi
 344
 345         if ns_is_validating ${ns} ${args}; then
 346                 # Return 0 if validating
 347                 return 0
 348         else
 349                 # Is DNSSEC-aware
 350                 return 2
 351         fi
 352 }
 353
 354 # Sends an A query to the nameserver w/o DNSSEC
 355 ns_is_online() {
 356         local ns=${1}
 357         shift
 358
 359         dig @${ns} +nodnssec A ${TEST_DOMAIN} $@ >/dev/null
 360 }
 361
 362 # Resolving ${TEST_DOMAIN_FAIL} will fail if the nameserver is validating
 363 ns_is_validating() {
 364         local ns=${1}
 365         shift
 366
 367         dig @${ns} A ${TEST_DOMAIN_FAIL} $@ | grep -q SERVFAIL
 368 }
 369
 370 # Checks if we can retrieve the DNSKEY for this domain.
 371 # dig will print the SOA if nothing was found
 372 ns_forwards_DNSKEY() {
 373         local ns=${1}
 374         shift
 375
 376         dig @${ns} DNSKEY ${TEST_DOMAIN} $@ | grep -qv SOA
 377 }
 378
 379 ns_forwards_DS() {
 380         local ns=${1}
 381         shift
 382
 383         dig @${ns} DS ${TEST_DOMAIN} $@ | grep -qv SOA
 384 }
 385
 386 ns_forwards_RRSIG() {
 387         local ns=${1}
 388         shift
 389
 390         dig @${ns} +dnssec A ${TEST_DOMAIN} $@ | grep -q RRSIG
 391 }
 392
 393 ns_supports_tcp() {
 394         local ns=${1}
 395         shift
 396
 397         dig @${ns} +tcp A ${TEST_DOMAIN} $@ >/dev/null || return 1
 398 }
 399
 400 ns_determine_edns_buffer_size() {
 401         local ns=${1}
 402         shift
 403
 404         local b
 405         for b in 4096 2048 1500 1480 1464 1400 1280 512; do
 406                 if dig @${ns} +dnssec +bufsize=${b} A ${TEST_DOMAIN} $@ >/dev/null; then
 407                         echo "${b}"
 408                         return 0
 409                 fi
 410         done
 411
 412         return 1
 413 }
 414
 415 get_root_nameservers() {
 416         while read -r hostname ttl record address; do
 417                 # Searching for A records
 418                 [ "${record}" = "A" ] || continue
 419
 420                 echo "${address}"
 421         done < /etc/unbound/root.hints
 422 }
 423
 424 can_resolve_root() {
 425         local ns
 426         for ns in $(get_root_nameservers); do
 427                 if dig @${ns} +dnssec SOA . $@ >/dev/null; then
 428                         return 0
 429                 fi
 430         done
 431
 432         # none of the servers was reachable
 433         return 1
 434 }
 435
 436 enable_dnssec() {
 437         local status=$(unbound-control get_option val-permissive-mode)
 438
 439         # Log DNSSEC status
 440         echo "on" > /var/ipfire/red/dnssec-status
 441
 442         # Don't do anything if DNSSEC is already activated
 443         [ "${status}" = "no" ] && return 0
 444
 445         # Activate DNSSEC and flush cache with any stale and unvalidated data
 446         unbound-control -q set_option val-permissive-mode: no
 447         unbound-control -q flush_zone .
 448 }
 449
 450 disable_dnssec() {
 451         # Log DNSSEC status
 452         echo "off" > /var/ipfire/red/dnssec-status
 453
 454         unbound-control -q set_option val-permissive-mode: yes
 455 }
 456
 457 fix_time_if_dns_fail() {
 458         # If DNS still not work try to init ntp with
 459         # hardcoded ntp.ipfire.org (81.3.27.46)
 460         if [ -e /var/ipfire/red/active ]; then
 461                 host 0.ipfire.pool.ntp.org > /dev/null 2>&1
 462                 if [ "${?}" != "0" ]; then
 463                         boot_mesg "DNS still not work ... init time with ntp.ipfire.org at 81.3.27.46 ..."
 464                         loadproc /usr/local/bin/settime 81.3.27.46
 465                 fi
 466         fi
 467 }
 468
 469 case "$1" in
 470         start)
 471                 # Print a nicer messagen when unbound is already running
 472                 if pidofproc -s unbound; then
 473                         statusproc /usr/sbin/unbound
 474                         exit 0
 475                 fi
 476
 477                 eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings)
 478
 479                 # Create control keys at first run
 480                 if [ ! -r "/etc/unbound/unbound_control.key" ]; then
 481                         unbound-control-setup -d /etc/unbound &>/dev/null
 482                 fi
 483
 484                 # Update configuration files
 485                 write_tuning_conf
 486                 write_forward_conf
 487
 488                 boot_mesg "Starting Unbound DNS Proxy..."
 489                 loadproc /usr/sbin/unbound || exit $?
 490
 491                 # Make own hostname resolveable
 492                 own_hostname
 493
 494                 # Update any known forwarding name servers
 495                 update_forwarders
 496
 497                 # Update hosts
 498                 update_hosts
 499
 500                 fix_time_if_dns_fail
 501                 ;;
 502
 503         stop)
 504                 boot_mesg "Stopping Unbound DNS Proxy..."
 505                 killproc /usr/sbin/unbound
 506                 ;;
 507
 508         restart)
 509                 $0 stop
 510                 sleep 1
 511                 $0 start
 512                 ;;
 513
 514         status)
 515                 statusproc /usr/sbin/unbound
 516                 ;;
 517
 518         update-forwarders)
 519                 # Do not try updating forwarders when unbound is not running
 520                 if ! pgrep unbound &>/dev/null; then
 521                         exit 0
 522                 fi
 523
 524                 update_forwarders
 525
 526                 unbound-control flush_negative > /dev/null
 527                 unbound-control flush_bogus > /dev/null
 528
 529                 fix_time_if_dns_fail
 530                 ;;
 531
 532         test-name-server)
 533                 ns=${2}
 534
 535                 test_name_server ${ns}
 536                 ret=${?}
 537
 538                 case "${ret}" in
 539                         0)
 540                                 echo "${ns} is validating"
 541                                 ;;
 542                         2)
 543                                 echo "${ns} is DNSSEC-aware"
 544                                 ;;
 545                         3)
 546                                 echo "${ns} is NOT DNSSEC-aware"
 547                                 ;;
 548                         *)
 549                                 echo "Test failed for an unknown reason"
 550                                 exit ${ret}
 551                                 ;;
 552                 esac
 553
 554                 if ns_supports_tcp ${ns}; then
 555                         echo "${ns} supports TCP fallback"
 556                 else
 557                         echo "${ns} does not support TCP fallback"
 558                 fi
 559
 560                 edns_buffer_size=$(ns_determine_edns_buffer_size ${ns})
 561                 if [ -n "${edns_buffer_size}" ]; then
 562                         echo "EDNS buffer size for ${ns}: ${edns_buffer_size}"
 563                 fi
 564
 565                 exit ${ret}
 566                 ;;
 567
 568         *)
 569                 echo "Usage: $0 {start|stop|restart|status|update-forwarders|test-name-server}"
 570                 exit 1
 571                 ;;
 572 esac
 573
 574 # End $rc_base/init.d/unbound