usr.sbin/bsdconfig/networking/share/resolv.subr

   1 if [ ! "$_NETWORKING_RESOLV_SUBR" ]; then _NETWORKING_RESOLV_SUBR=1
   2 #
   3 # Copyright (c) 2006-2013 Devin Teske
   4 # All rights reserved.
   5 #
   6 # Redistribution and use in source and binary forms, with or without
   7 # modification, are permitted provided that the following conditions
   8 # are met:
   9 # 1. Redistributions of source code must retain the above copyright
  10 #    notice, this list of conditions and the following disclaimer.
  11 # 2. Redistributions in binary form must reproduce the above copyright
  12 #    notice, this list of conditions and the following disclaimer in the
  13 #    documentation and/or other materials provided with the distribution.
  14 #
  15 # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18 # ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19 # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20 # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21 # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22 # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23 # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24 # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25 # SUCH DAMAGE.
  26 #
  27 # $FreeBSD$
  28 #
  29 ############################################################ INCLUDES
  30
  31 BSDCFG_SHARE="/usr/share/bsdconfig"
  32 . $BSDCFG_SHARE/common.subr || exit 1
  33 f_dprintf "%s: loading includes..." networking/resolv.subr
  34 f_include $BSDCFG_SHARE/dialog.subr
  35 f_include $BSDCFG_SHARE/media/tcpip.subr
  36 f_include $BSDCFG_SHARE/networking/common.subr
  37 f_include $BSDCFG_SHARE/networking/ipaddr.subr
  38 f_include $BSDCFG_SHARE/strings.subr
  39
  40 BSDCFG_LIBE="/usr/libexec/bsdconfig" APP_DIR="120.networking"
  41 f_include_lang $BSDCFG_LIBE/$APP_DIR/include/messages.subr
  42
  43 ############################################################ CONFIGURATION
  44
  45 #
  46 # When updating resolv.conf(5), should we populate the `search' directive with
  47 # all possible sub-domains? In example, if the domain is "sub.domain.com", when
  48 # the below option is set to 1, include both "sub.domain.com" and "domain.com"
  49 # in the `search' directive, otherwise use only "sub.domain.com".
  50 #
  51 # When enabled (set to 1), specify the minimum number of dots required for each
  52 # `search' domain by setting the second option below, `RESOLVER_SEARCH_NDOTS'.
  53 #
  54 : ${RESOLVER_SEARCH_DOMAINS_ALL:=1}
  55 : ${RESOLVER_SEARCH_NDOTS:=1}
  56
  57 ############################################################ FUNCTIONS
  58
  59 # f_resolv_conf_domain
  60 #
  61 # Returns the domain configured in resolv.conf(5).
  62 #
  63 f_resolv_conf_domain()
  64 {
  65         tail -r "$RESOLV_CONF" 2> /dev/null | awk \
  66         '
  67                 BEGIN { found = 0 }
  68                 ( tolower($1) == "domain" ) \
  69                 {
  70                         print $2
  71                         found = 1
  72                         exit
  73                 }
  74                 END { exit ! found }
  75         '
  76 }
  77
  78 # f_resolv_conf_search
  79 #
  80 # Returns the search configured in resolv.conf(5).
  81 #
  82 f_resolv_conf_search()
  83 {
  84         tail -r "$RESOLV_CONF" 2> /dev/null | awk \
  85         '
  86                 BEGIN { found = 0 }
  87                 {
  88                         tl0 = tolower($0)
  89                         if ( match(tl0, /^[[:space:]]*search[[:space:]]+/) ) {
  90                                 search = substr($0, RLENGTH + 1)
  91                                 sub(/[[:space:]]*#.*$/, "", search)
  92                                 gsub(/[[:space:]]+/, " ", search)
  93                                 print search
  94                                 found = 1
  95                                 exit
  96                         }
  97                 }
  98                 END { exit ! found }
  99         '
 100 }
 101
 102 # f_dialog_resolv_conf_update $hostname
 103 #
 104 # Updates the search/domain directives in resolv.conf(5) given a valid fully-
 105 # qualified hostname.
 106 #
 107 # This function is a two-parter. Below is the awk(1) portion of the function,
 108 # afterward is the sh(1) function which utilizes the below awk script.
 109 #
 110 f_dialog_resolv_conf_update_awk='
 111 # Variables that should be defined on the invocation line:
 112 #       -v domain="domain"
 113 #       -v search_all="0|1"
 114 #       -v search_ndots="1+"
 115 #
 116 BEGIN {
 117         domain_found = search_found = 0
 118
 119         if ( search_all ) {
 120                 search = ""
 121                 subdomain = domain
 122                 if ( search_ndots < 1 )
 123                         search_ndots = 1
 124
 125                 ndots = split(subdomain, labels, ".") - 1
 126                 while ( ndots-- >= search_ndots ) {
 127                         if ( length(search) ) search = search " "
 128                         search = search subdomain
 129                         sub(/[^.]*\./, "", subdomain)
 130                 }
 131         }
 132         else search = domain
 133 }
 134 {
 135         if ( domain_found && search_found ) { print; next }
 136
 137         tl0 = tolower($0)
 138         if ( ! domain_found && \
 139              match(tl0, /^[[:space:]]*domain[[:space:]]+/) ) \
 140         {
 141                 if ( length(domain) ) {
 142                         printf "%s%s\n", substr($0, 0, RLENGTH), domain
 143                         domain_found = 1
 144                 }
 145         }
 146         else if ( ! search_found && \
 147                   match(tl0, /^[[:space:]]*search[[:space:]]+/) ) \
 148         {
 149                 if ( length(search) ) {
 150                         printf "%s%s\n", substr($0, 0, RLENGTH), search
 151                         search_found = 1
 152                 }
 153         }
 154         else print
 155 }
 156 END {
 157         if ( ! search_found && length(search) )
 158                 printf "search\t%s\n", search
 159         if ( ! domain_found && length(domain) )
 160                 printf "domain\t%s\n", domain
 161 }
 162 '
 163 f_dialog_resolv_conf_update()
 164 {
 165         local hostname="$1"
 166
 167         #
 168         # Extrapolate the desired domain search parameter for resolv.conf(5)
 169         #
 170         local search ndots domain="${hostname#*.}"
 171         if [ "$RESOLVER_SEARCH_DOMAINS_ALL" = "1" ]; then
 172                 search=""
 173                 ndots=$( IFS=.; set -- $domain; echo $(( $# - 1 )) )
 174                 while [ $ndots -ge ${RESOLVER_SEARCH_NDOTS:-1} ]; do
 175                         search="$search${search:+ }$domain"
 176                         domain="${domain#*.}"
 177                         ndots=$(( $ndots - 1 ))
 178                 done
 179                 domain="${hostname#*.}"
 180         else
 181                 search="$domain"
 182         fi
 183
 184         #
 185         # Save domain/search information only if different from resolv.conf(5)
 186         #
 187         if [ "$domain" != "$( f_resolv_conf_domain )" -o \
 188              "$search" != "$( f_resolv_conf_search )" ]
 189         then
 190                 f_dialog_info "Saving new domain/search settings" \
 191                               "to resolv.conf(5)..."
 192
 193                 #
 194                 # Create a new temporary file to write our resolv.conf(5)
 195                 # update with our new `domain' and `search' directives.
 196                 #
 197                 local tmpfile="$( mktemp -t "$pgm" )"
 198                 [ "$tmpfile" ] || return $FAILURE
 199
 200                 #
 201                 # Fixup permissions and ownership (mktemp(1) creates the
 202                 # temporary file with 0600 permissions -- change the
 203                 # permissions and ownership to match resolv.conf(5) before
 204                 # we write it out and mv(1) it into place).
 205                 #
 206                 local mode="$( stat -f '%#Lp' "$RESOLV_CONF" 2> /dev/null )"
 207                 local owner="$( stat -f '%u:%g' "$RESOLV_CONF" 2> /dev/null )"
 208                 f_quietly chmod "${mode:-0644}" "$tmpfile"
 209                 f_quietly chown "${owner:-root:wheel}" "$tmpfile"
 210
 211                 #
 212                 # Operate on resolv.conf(5), replacing only the last
 213                 # occurrences of `domain' and `search' directives (or add
 214                 # them to the top if not found), in strict-adherence to the
 215                 # following entry in resolver(5):
 216                 #
 217                 #       The domain and search keywords are mutually exclusive.
 218                 #       If more than one instance of these keywords is present,
 219                 #       the last instance will override.
 220                 #
 221                 # NOTE: If RESOLVER_SEARCH_DOMAINS_ALL is set to `1' in the
 222                 # environment, all sub-domains will be added to the `search'
 223                 # directive, not just the FQDN.
 224                 #
 225                 local domain="${hostname#*.}" new_contents
 226                 [ "$domain" = "$hostname" ] && domain=
 227                 new_contents=$( tail -r "$RESOLV_CONF" 2> /dev/null )
 228                 new_contents=$( echo "$new_contents" | awk \
 229                         -v domain="$domain" \
 230                         -v search_all="${RESOLVER_SEARCH_DOMAINS_ALL:-1}" \
 231                         -v search_ndots="${RESOLVER_SEARCH_NDOTS:-1}" \
 232                         "$f_dialog_resolv_conf_update_awk" )
 233
 234                 #
 235                 # Write the temporary file contents and move the temporary
 236                 # file into place.
 237                 #
 238                 echo "$new_contents" | tail -r > "$tmpfile" || return $FAILURE
 239                 f_quietly mv "$tmpfile" "$RESOLV_CONF"
 240
 241         fi
 242 }
 243
 244 # f_dialog_input_nameserver [ $n $nameserver ]
 245 #
 246 # Allows the user to edit a given nameserver. The first argument is the
 247 # resolv.conf(5) nameserver ``instance'' integer. For example, this will be one
 248 # if editing the first nameserver instance, two if editing the second, three if
 249 # the third, ad nauseum. If this argument is zero, null, or missing, the value
 250 # entered by the user (if non-null) will be added to resolv.conf(5) as a new
 251 # `nameserver' entry. The second argument is the IPv4 address of the nameserver
 252 # to be edited -- this will be displayed as the initial value during the edit.
 253 #
 254 # Taint-checking is performed when editing an existing entry (when the second
 255 # argument is one or higher) in that the first argument must match the current
 256 # value of the Nth `nameserver' instance in resolv.conf(5) else an error is
 257 # generated discarding any/all changes.
 258 #
 259 # This function is a two-parter. Below is the awk(1) portion of the function,
 260 # afterward is the sh(1) function which utilizes the below awk script.
 261 #
 262 f_dialog_input_nameserver_edit_awk='
 263 # Variables that should be defined on the invocation line:
 264 #       -v nsindex="1+"
 265 #       -v old_value="..."
 266 #       -v new_value="..."
 267 #
 268 BEGIN {
 269         if ( nsindex < 1 ) exit 1
 270         found = n = 0
 271 }
 272 {
 273         if ( found ) { print; next }
 274
 275         if ( match(tolower($0), /^[[:space:]]*nameserver[[:space:]]+/)) {
 276                 if ( ++n == nsindex ) {
 277                         if ( $2 != old_value ) exit 2
 278                         if ( new_value != "" ) printf "%s%s\n", \
 279                                 substr($0, 0, RLENGTH), new_value
 280                         found = 1
 281                 }
 282                 else print
 283         }
 284         else print
 285 }
 286 END { if ( ! found ) exit 3 }
 287 '
 288 f_dialog_input_nameserver()
 289 {
 290         local index="${1:-0}" old_ns="$2" new_ns
 291         local ns="$old_ns"
 292
 293         #
 294         # Perform sanity checks
 295         #
 296         f_isinteger "$index" || return $FAILURE
 297         [ $index -ge 0 ] || return $FAILURE
 298
 299         local msg
 300         if [ $index -gt 0 ]; then
 301                 if [ "$USE_XDIALOG" ]; then
 302                         msg="$xmsg_please_enter_nameserver_existing"
 303                 else
 304                         msg="$msg_please_enter_nameserver_existing"
 305                 fi
 306         else
 307                 msg="$msg_please_enter_nameserver"
 308         fi
 309
 310         #
 311         # Loop until the user provides taint-free input.
 312         #
 313         while :; do
 314                 f_dialog_input new_ns "$msg" "$ns" \
 315                                "$hline_num_punc_tab_enter" || return
 316
 317                 # Take only the first "word" of the user's input
 318                 new_ns="${new_ns%%[$IFS]*}"
 319
 320                 # Taint-check the user's input
 321                 [ "$new_ns" ] || break
 322                 f_dialog_validate_ipaddr "$new_ns" && break
 323
 324                 # Update prompt to allow user to re-edit previous entry
 325                 ns="$new_ns"
 326         done
 327
 328         #
 329         # Save only if the user changed the nameserver.
 330         #
 331         if [ $index -eq "0" -a "$new_ns" ]; then
 332                 f_dialog_info "$msg_saving_nameserver"
 333                 printf "nameserver\t%s\n" "$new_ns" >> "$RESOLV_CONF"
 334                 return $SUCCESS
 335         elif [ $index -gt 0 -a "$old_ns" != "$new_ns" ]; then
 336                 if [ "$new_ns" ]; then
 337                         msg="$msg_saving_nameserver_existing"
 338                 else
 339                         msg="$msg_removing_nameserver"
 340                 fi
 341                 f_dialog_info "$msg"
 342
 343                 #
 344                 # Create a new temporary file to write our new resolv.conf(5)
 345                 #
 346                 local tmpfile="$( mktemp -t "$pgm" )"
 347                 [ "$tmpfile" ] || return $FAILURE
 348
 349                 #
 350                 # Quietly fixup permissions and ownership
 351                 #
 352                 local mode owner
 353                 mode=$( stat -f '%#Lp' "$RESOLV_CONF" 2> /dev/null )
 354                 owner=$( stat -f '%u:%g' "$RESOLV_CONF" 2> /dev/null )
 355                 f_quietly chmod "${mode:-0644}" "$tmpfile"
 356                 f_quietly chown "${owner:-root:wheel}" "$tmpfile"
 357
 358                 #
 359                 # Operate on resolv.conf(5)
 360                 #
 361                 local new_contents
 362                 new_contents=$( awk -v nsindex="$index"    \
 363                                     -v old_value="$old_ns" \
 364                                     -v new_value="$new_ns" \
 365                                     "$f_dialog_input_nameserver_edit_awk" \
 366                                     "$RESOLV_CONF" )
 367
 368                 #
 369                 # Produce an appropriate error message if necessary.
 370                 #
 371                 local retval=$?
 372                 case $retval in
 373                 1) f_die 1 "$msg_internal_error_nsindex_value" "$nsindex" ;;
 374                 2) f_show_msg "$msg_resolv_conf_changed_while_editing"
 375                    return $retval ;;
 376                 3) f_show_msg "$msg_resolv_conf_entry_no_longer_exists"
 377                    return $retval ;;
 378                 esac
 379
 380                 #
 381                 # Write the temporary file contents and move the temporary
 382                 # file into place.
 383                 #
 384                 echo "$new_contents" > "$tmpfile" || return $FAILURE
 385                 f_quietly mv "$tmpfile" "$RESOLV_CONF"
 386         fi
 387 }
 388
 389 # f_dialog_menu_nameservers
 390 #
 391 # Edit the nameservers in resolv.conf(5).
 392 #
 393 f_dialog_menu_nameservers()
 394 {
 395         local prompt="$msg_dns_configuration"
 396         local menu_list # Calculated below
 397         local hline="$hline_arrows_tab_enter"
 398         local defaultitem=
 399
 400         local height width rows
 401         local opt_exit="$msg_return_to_previous_menu"
 402         local opt_add="$msg_add_nameserver"
 403
 404         #
 405         # Loop forever until the user has finished configuring nameservers
 406         #
 407         while :; do
 408                 #
 409                 # Re/Build list of nameservers
 410                 #
 411                 local nameservers="$( f_resolv_conf_nameservers )"
 412                 menu_list=$(
 413                         index=1
 414
 415                         echo "'X $msg_exit' '$opt_exit'"
 416                         index=$(( $index + 1 ))
 417
 418                         echo "'A $msg_add'  '$opt_add'"
 419                         index=$(( $index + 1 ))
 420
 421                         for ns in $nameservers; do
 422                                 [ $index -lt ${#DIALOG_MENU_TAGS} ] || break
 423                                 tag=$( f_substr "$DIALOG_MENU_TAGS" $index 1 )
 424                                 echo "'$tag nameserver' '$ns'"
 425                                 index=$(( $index + 1 ))
 426                         done
 427                 )
 428
 429                 #
 430                 # Display configuration-edit menu
 431                 #
 432                 eval f_dialog_menu_size height width rows \
 433                                         \"\$DIALOG_TITLE\"     \
 434                                         \"\$DIALOG_BACKTITLE\" \
 435                                         \"\$prompt\"           \
 436                                         \"\$hline\"            \
 437                                         $menu_list
 438                 local tag
 439                 tag=$( eval $DIALOG \
 440                         --title \"\$DIALOG_TITLE\"         \
 441                         --backtitle \"\$DIALOG_BACKTITLE\" \
 442                         --hline \"\$hline\"                \
 443                         --ok-label \"\$msg_ok\"            \
 444                         --cancel-label \"\$msg_cancel\"    \
 445                         --default-item \"\$defaultitem\"   \
 446                         --menu \"\$prompt\"                \
 447                         $height $width $rows               \
 448                         $menu_list                         \
 449                         2>&1 >&$DIALOG_TERMINAL_PASSTHRU_FD
 450                 )
 451                 local retval=$?
 452                 f_dialog_data_sanitize tag
 453
 454                 # Return if "Cancel" was chosen (-1) or ESC was pressed (255)
 455                 if [ $retval -ne $SUCCESS ]; then
 456                         return $retval
 457                 else
 458                         # Only update default-item on success
 459                         defaultitem="$tag"
 460                 fi
 461
 462                 case "$tag" in
 463                 "X $msg_exit") break ;;
 464                 "A $msg_add")
 465                         f_dialog_input_nameserver
 466                         ;;
 467                 *)
 468                         local n ns
 469                         n=$( eval f_dialog_menutag2index \"\$tag\" $menu_list )
 470                         ns=$( eval f_dialog_menutag2item \"\$tag\" $menu_list )
 471                         f_dialog_input_nameserver $(( $n - 2 )) "$ns"
 472                         ;;
 473                 esac
 474         done
 475 }
 476
 477 ############################################################ MAIN
 478
 479 f_dprintf "%s: Successfully loaded." networking/resolv.subr
 480
 481 fi # ! $_NETWORKING_RESOLV_SUBR