src/plugins/bind.sml

   1 (* HCoop Domtool (http://hcoop.sourceforge.net/)
   2  * Copyright (c) 2006, Adam Chlipala
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17  *)
  18
  19 (* BIND DNS *)
  20
  21 structure Bind :> BIND = struct
  22
  23 open Ast
  24
  25 val namedChanged = ref false
  26 val zoneChanged = ref false
  27
  28 val didDomain = ref ""
  29
  30 val () = Slave.registerPreHandler (fn () => (namedChanged := false;
  31                                              zoneChanged := false;
  32                                              didDomain := ""))
  33
  34 val dns : Domain.files option ref = ref NONE
  35
  36 val _ = Domain.registerBefore
  37             (fn _ => dns := Option.map (fn node => Domain.domainsFile {node = node,
  38                                                                        name = "dns"})
  39                                        (Domain.dnsMaster ()))
  40
  41 val _ = Domain.registerAfter
  42             (fn _ => (Option.app (fn files => #close files ()) (!dns);
  43                       dns := NONE))
  44
  45 val dl = ErrorMsg.dummyLoc
  46
  47 datatype dns_record =
  48          A of string * string
  49        | CNAME of string * string
  50        | MX of int * string
  51        | NS of string
  52        | DefaultA of string
  53
  54 val record = fn (EApp ((EApp ((EVar "dnsA", _), e1), _), e2), _) =>
  55                 (case (Env.string e1, Domain.ip e2) of
  56                      (SOME v1, SOME v2) => SOME (A (v1, v2))
  57                    | _ => NONE)
  58               | (EApp ((EApp ((EVar "dnsCNAME", _), e1), _), e2), _) =>
  59                 (case (Env.string e1, Env.string e2) of
  60                      (SOME v1, SOME v2) => SOME (CNAME (v1, v2))
  61                    | _ => NONE)
  62               | (EApp ((EApp ((EVar "dnsMX", _), e1), _), e2), _) =>
  63                 (case (Env.int e1, Env.string e2) of
  64                      (SOME v1, SOME v2) => SOME (MX (v1, v2))
  65                    | _ => NONE)
  66               | (EApp ((EVar "dnsNS", _), e), _) =>
  67                 Option.map NS (Env.string e)
  68               | (EApp ((EVar "dnsDefaultA", _), e), _) =>
  69                 Option.map DefaultA (Env.string e)
  70               | _ => NONE
  71
  72 fun writeRecord (evs, r) =
  73     case !dns of
  74         NONE => print "Warning: DNS directive ignored because no master DNS server is configured for this domain\n"
  75       | SOME files =>
  76         let
  77             fun write s = #write files s
  78             fun writeDom () = #writeDom files ()
  79             val ttl = Env.env Env.int (evs, "TTL")
  80         in
  81             case r of
  82                 A (from, to) => (write from;
  83                                  write ".";
  84                                  writeDom ();
  85                                  write ".\t";
  86                                  write (Int.toString ttl);
  87                                  write "\tIN\tA\t";
  88                                  write to;
  89                                  write "\n")
  90               | DefaultA to => (writeDom ();
  91                                 write ".\t";
  92                                 write (Int.toString ttl);
  93                                 write "\tIN\tA\t";
  94                                 write to;
  95                                 write "\n")
  96               | CNAME (from, to) => (write from;
  97                                      write ".";
  98                                      writeDom ();
  99                                      write ".\t";
 100                                      write (Int.toString ttl);
 101                                      write "\tIN\tCNAME\t";
 102                                      write to;
 103                                      write ".\n")
 104               | MX (num, host) => (write "\t";
 105                                    write (Int.toString ttl);
 106                                    write "\tIN\tMX\t";
 107                                    write (Int.toString num);
 108                                    write "\t";
 109                                    write host;
 110                                    write ".\n")
 111               | NS host => (write "\t";
 112                             write (Int.toString ttl);
 113                             write "\tIN\tNS\t";
 114                             write host;
 115                             write ".\n")
 116         end
 117
 118 val () = Env.actionV_one "dns"
 119                          ("record", record)
 120                          writeRecord
 121
 122 fun readLine inf =
 123     case TextIO.inputLine inf of
 124         NONE => raise Fail "Expected a line for BIND"
 125       | SOME s => String.substring (s, 0, size s - 1)
 126
 127 fun readILine inf = valOf (Int.fromString (readLine inf))
 128
 129 val monthToInt = fn Date.Jan => 1
 130                   | Date.Feb => 2
 131                   | Date.Mar => 3
 132                   | Date.Apr => 4
 133                   | Date.May => 5
 134                   | Date.Jun => 6
 135                   | Date.Jul => 7
 136                   | Date.Aug => 8
 137                   | Date.Sep => 9
 138                   | Date.Oct => 10
 139                   | Date.Nov => 11
 140                   | Date.Dec => 12
 141
 142 fun padBy ch amt s =
 143     if size s < amt then
 144         CharVector.tabulate (amt - size s, fn _ => ch) ^ s
 145     else
 146         s
 147
 148 fun dateString () =
 149     let
 150         val date = Date.fromTimeUniv (Time.now ())
 151     in
 152         padBy #"0" 4 (Int.toString (Date.year date))
 153         ^ padBy #"0" 2 (Int.toString (monthToInt (Date.month date)))
 154         ^ padBy #"0" 2 (Int.toString (Date.day date))
 155     end
 156
 157 val () = Slave.registerFileHandler (fn fs =>
 158                                        let
 159                                            val {dir, file} = OS.Path.splitDirFile (#file fs)
 160
 161                                            fun dnsChanged () =
 162                                                if #domain fs = !didDomain then
 163                                                    ()
 164                                                else if #action fs = Slave.Delete then
 165                                                    let
 166                                                        val fname = OS.Path.joinBaseExt {base = #domain fs,
 167                                                                                         ext = SOME "zone"}
 168                                                        val fname = OS.Path.joinDirFile {dir = Config.Bind.zonePath,
 169                                                                                         file = fname}
 170                                                    in
 171                                                        Slave.shellF ([Config.rm, " -f ", fname],
 172                                                                   fn cl => "Error deleting file: " ^ cl)
 173                                                    end
 174                                                else
 175                                                    let
 176                                                        val inf = TextIO.openIn (OS.Path.joinDirFile {dir = #dir fs,
 177                                                                                                      file = "soa"})
 178                                                        val kind = readLine inf
 179                                                        val ttl = readILine inf
 180                                                        val ns = readLine inf
 181                                                        val serial = case readLine inf of
 182                                                                         "" => NONE
 183                                                                       | s => Int.fromString s
 184                                                        val rf = readILine inf
 185                                                        val ret = readILine inf
 186                                                        val exp = readILine inf
 187                                                        val min = readILine inf
 188                                                        val () = TextIO.closeIn inf
 189
 190                                                        val serialPath = OS.Path.joinDirFile {dir = Config.serialDir,
 191                                                                                              file = #domain fs}
 192
 193                                                        val oldSerial = let
 194                                                            val inf = TextIO.openIn serialPath
 195                                                        in
 196                                                            SOME (readLine inf)
 197                                                            before TextIO.closeIn inf
 198                                                        end handle IO.Io {name, ...} => NONE
 199
 200                                                        val newSerial =
 201                                                            case serial of
 202                                                                SOME n => Int.toString n
 203                                                              | NONE =>
 204                                                                let
 205                                                                    val prefix = dateString ()
 206                                                                in
 207                                                                    prefix
 208                                                                    ^ (case oldSerial of
 209                                                                           NONE => "00"
 210                                                                         | SOME old =>
 211                                                                           if size old >= 8 andalso
 212                                                                              String.substring (old, 0, 8) = prefix then
 213                                                                               case Int.fromString (String.extract (old, 8, NONE)) of
 214                                                                                   NONE => "00"
 215                                                                                 | SOME old => padBy #"0" 2 (Int.toString (old+1))
 216                                                                           else
 217                                                                               "00")
 218                                                                end
 219
 220                                                        val outf = TextIO.openOut serialPath
 221                                                        val _ = TextIO.output (outf, newSerial)
 222                                                        val _ = TextIO.closeOut outf
 223
 224                                                        val dns = OS.Path.joinDirFile {dir = #dir fs,
 225                                                                                       file = "dns"}
 226
 227                                                        val fname = OS.Path.joinBaseExt {base = #domain fs,
 228                                                                                         ext = SOME "zone"}
 229                                                        val fname = OS.Path.joinDirFile {dir = Config.Bind.zonePath,
 230                                                                                         file = fname}
 231
 232                                                        val outf = TextIO.openOut fname
 233                                                    in
 234                                                        zoneChanged := true;
 235                                                        TextIO.output (outf, "$TTL ");
 236                                                        TextIO.output (outf, Int.toString ttl);
 237                                                        TextIO.output (outf, "\n\n@\tIN\tSOA\t");
 238                                                        TextIO.output (outf, ns);
 239                                                        TextIO.output (outf, ".\thostmaster.");
 240                                                        TextIO.output (outf, #domain fs);
 241                                                        TextIO.output (outf, ". ( ");
 242                                                        TextIO.output (outf, newSerial);
 243                                                        TextIO.output (outf, " ");
 244                                                        TextIO.output (outf, Int.toString rf);
 245                                                        TextIO.output (outf, " ");
 246                                                        TextIO.output (outf, Int.toString ret);
 247                                                        TextIO.output (outf, " ");
 248                                                        TextIO.output (outf, Int.toString exp);
 249                                                        TextIO.output (outf, " ");
 250                                                        TextIO.output (outf, Int.toString min);
 251                                                        TextIO.output (outf, " )\n\n");
 252                                                        TextIO.closeOut outf;
 253                                                        if Posix.FileSys.access (dns, []) then
 254                                                            Slave.shellF ([Config.cat, " ", dns, " >>", fname],
 255                                                                       fn cl => "Error concatenating file: " ^ cl)
 256                                                        else
 257                                                            ();
 258                                                        didDomain := #domain fs
 259                                                    end
 260                                        in
 261                                            case file of
 262                                                "soa" => dnsChanged ()
 263                                              | "dns" => dnsChanged ()
 264                                              | "named.conf" => namedChanged := true
 265                                              | _ => ()
 266                                        end)
 267
 268 val () = Slave.registerPostHandler
 269              (fn () =>
 270                  (if !namedChanged then
 271                       Slave.concatTo (fn s => s = "named.conf") Config.Bind.namedConf
 272                   else
 273                      ();
 274                   if !namedChanged orelse !zoneChanged then
 275                       Slave.shellF ([Config.Bind.reload],
 276                                  fn cl => "Error reloading bind with " ^ cl)
 277                   else
 278                       ()))
 279
 280 val () = Domain.registerResetLocal (fn () =>
 281                                        ignore (OS.Process.system (Config.rm ^ " -rf /var/domtool/zones/*")))
 282
 283 end