named.js

var iputils = require("./iputils");
var wait = new (require("./Wait"));

// probably a complete implementation of the legacy namecoin format.
// (modulo a crapton of bugs.)

// XXX: the translate stuff doesn't quite work. ie. www.qr.bit works, but qr.bit doesn't.

function generateNamedConf(obj, confname, dbname, callback) {
    var config = [ 
      "# This file was generated by "+process.argv[1]+" on "+new Date, 
      '',
      'zone "bit" { type master; file "'+dbname+'"; allow-query { any; }; };'
    ]; // will hold the named.conf entries
    var dbconfig = [
	// The values in here are probably horribly inappropriate. XXX
      "; This file was generated by "+process.argv[1]+" on "+new Date, 
      "$TTL 14400",
      "$ORIGIN bit.",
      "",
      "; Specify the primary nameserver ns1.bit in SOA",
      "@ 14400 IN SOA ns1.bit. webmaster.bit. (",
      "                          2008092902 ; Serial in YYYYMMDDXX (XX is increment)",
      "                          10800; refresh seconds",
      "                          3600; retry",
      "                          604800; expire",
      "                          38400; minimum",
      "                          );",
      "",
      "       IN NS ns1.bit.",
      "ns1  IN A 127.0.0.1",
      ""
    ];

    function addDbLine(sub, domain, dst) {
      var host = (sub==""?domain:sub+"."+domain);
      if (!iputils.isPlausibleDomain(host)) return;
      if (iputils.isIPv4Address(dst)) {
        if (iputils.isRoutableIPv4Address(dst)) {
	  dbconfig.push(host+"  IN A "+dst);
	  dbconfig.push("*."+host+"  IN A "+dst);
        }
      } else {
        iputils.lookupDomain(dst, wait.for(function(err,data) {
          if (!err) {
            addDbLine(sub, domain, data);
          }
        }));
      }
    }
    function addDbTranslate(sub, domain, dst) {
      var host = (sub==""?domain:sub+"."+domain);
      if (!iputils.isPlausibleDomain(host)) return;
      if (!iputils.isPlausibleDomain(dst)) return;
      dbconfig.push(host+"  IN DNAME "+dst+".");
    }

    function addZone(sub, domain, nss) {
      var host = (sub==""?domain:sub+"."+domain)+".bit";
      var forwarders = [];
      if (!iputils.isPlausibleDomain(host)) return;
      for (var i=0;i<nss.length;i++) {
        if (!iputils.isIPv4Address(nss[i])) {
          // we need to resolve. start resolve and postpone the rest.
          iputils.lookupDomain(nss[i], wait.for(function(err, data) {
            if (!err) {
              nss[i] = data;
            } else {
              // doesn't resolve. remove item from array.
              nss.splice(i,1);
            }
            addZone(sub, domain, nss);
          }));
          return;
        } else {
          // make sure we're routable.
          if (iputils.isRoutableIPv4Address(nss[i])) {
            forwarders.push(nss[i]);
          } else {
            // drop.
          }
        }
      }
      if (forwarders.length>0) {
        // we have at least one valid DNS server left. okay.
        config.push('zone "'+host+'" { type forward; forwarders { '+forwarders.join("; ")+"; }; };");
      }
    }

    for (var name in obj) {
      var value = obj[name];
      if (value.map) {
        for (var key in value.map) {
          var item = value.map[key];
          //console.log("looking at "+name+" value="+value.map+", item is "+JSON.stringify(item));
          if (typeof item == "string") {
            addDbLine(key, name, item);
          } else if (item) {
            // probably an object. check for "ns" and "translate" fields.
            if (item.translate) {
              addDbTranslate(key, name, item.translate);
	      // if translate, no zone forwarders. until i figure out how to mix the two.
            } else if (item.ns) {
              if (item.ns instanceof Array) {
                // multiple NS. no problem.
                addZone(key, name, item.ns);
              } else if (typeof item.ns == "string") {
                // not sure if legit. accept for now. XXX
                addZone(key, name, [item.ns]);
              } else {
                // bogus ns field. ignore.
              }
            }
          } else {
            // invalid map field. probably "null" or somesuch nonsense. ignore.
          }
        }
      }
    }

    wait.on("done", function () {
      var fs = require("fs");
      var data = config.join('\n');
      fs.writeFile(confname, data, 'utf8', function(){
        var data = dbconfig.join('\n');
        fs.writeFile(dbname, data, 'utf8', callback);
      });
    });
    wait.start();
}

module.exports = {
  generateNamedConf: generateNamedConf
};