On the fly signature for MX

lib/server/auth.js

@@ -23,6 +23,11 @@ class AuthServer extends DNSServer {
     this.initOptions(options);
   }
 
+  setZSKFromString(str) {
+    this.zone.setZSKFromString(str);
+    return this;
+  }
+
   setOrigin(name) {
     this.zone.setOrigin(name);
     return this;

lib/zone.js

@@ -14,6 +14,10 @@ const fs = require('bfile');
 const constants = require('./constants');
 const util = require('./util');
 const wire = require('./wire');
+const dnssec = require('./dnssec');
+const {keyFlags} = dnssec;
+const {ZONE} = keyFlags;
+
 
 const {
   types,
@@ -46,8 +50,10 @@ class Zone {
     this.origin = '.';
     this.count = 0;
     this.names = new Map();
-    this.wild = new RecordMap();
+    this.wild = new RecordMap(this);
     this.nsec = new NameList();
+    this.zskpriv = null;
+    this.zskkey = null;
     this.setOrigin(origin);
   }
 
@@ -65,6 +71,12 @@ class Zone {
     return this;
   }
 
+  setZSKFromString(str) {
+    const [alg, zskpriv] = dnssec.decodePrivate(str);
+    this.zskpriv = zskpriv;
+    this.zskkey = dnssec.makeKey(this.origin, alg, zskpriv, ZONE);
+  }
+
   setOrigin(origin) {
     if (origin == null)
       origin = '.';
@@ -95,7 +107,7 @@ class Zone {
       this.wild.insert(rr);
     } else {
       if (!this.names.has(rr.name))
-        this.names.set(rr.name, new RecordMap());
+        this.names.set(rr.name, new RecordMap(this));
 
       const map = this.names.get(rr.name);
 
@@ -121,8 +133,8 @@ class Zone {
 
     if (map)
       map.push(name, type, an);
-
-    this.wild.push(name, type, an);
+    else
+      this.wild.push(name, type, an);
 
     return this;
   }
@@ -145,27 +157,42 @@ class Zone {
     return map.rrs.has(type);
   }
 
-  glue(name, an) {
+  glue(name, an, type, ns) {
     assert(util.isFQDN(name));
     assert(Array.isArray(an));
 
-    this.push(name, types.A, an);
-    this.push(name, types.AAAA, an);
+    const initial = an.length;
+
+    if (!type) {
+      this.push(name, types.A, an);
+      this.push(name, types.AAAA, an);
+    } else {
+      this.push(name, type, an);
+    }
+
+    const final = an.length;
+
+    // If the only answer we have is a CNAME with no "glue",
+    // include an SOA in the authority section, just like
+    // if we had no answer for a name we're authoritative over.
+    if (initial === final)
+      this.push(name, types.SOA, ns);
 
     return this;
   }
 
   find(name, type) {
     const an = this.get(name, type);
     const ar = [];
+    const ns = [];
 
     for (const rr of an) {
       switch (rr.type) {
         case types.CNAME:
-          this.glue(rr.data.target, an);
+          this.glue(rr.data.target, an, type, ns);
           break;
         case types.DNAME:
-          this.glue(rr.data.target, an);
+          this.glue(rr.data.target, an, type, ns);
           break;
         case types.NS:
           this.glue(rr.data.ns, ar);
@@ -174,15 +201,15 @@ class Zone {
           this.glue(rr.data.ns, ar);
           break;
         case types.MX:
-          this.glue(rr.data.mx, ar);
+          this.glue(util.fqdn(rr.data.mx), ar, type, ns);
           break;
         case types.SRV:
           this.glue(rr.data.target, ar);
           break;
       }
     }
 
-    return [an, ar];
+    return [an, ar, ns];
   }
 
   getHints() {
@@ -230,12 +257,17 @@ class Zone {
     assert(util.isFQDN(name));
     assert((type & 0xffff) === type);
 
-    const [an, ar] = this.find(name, type);
+    const labels = util.split(name);
+    const zone = util.from(name, labels, -this.count);
+    const authority = util.equal(zone, this.origin);
+
+    let [an, ar, ns] = this.find(name, type);
+    let glue;
 
     // Do we have an answer?
     if (an.length > 0) {
       // Are we authoritative for this name?
-      if (!this.has(name, types.SOA)) {
+      if (!authority) {
         // If we're not authoritative for this
         // name, this is probably a request
         // for a DS or NSEC record.
@@ -246,34 +278,17 @@ class Zone {
           return [[], an, ar, false, true];
         }
 
-        // Send the answer but do
-        // not set the `aa` bit.
         return [an, [], ar, false, true];
       }
 
       // We're authoritative. Send the
       // answer and set the `aa` bit.
-      return [an, [], ar, true, true];
-    }
-
-    const labels = util.split(name);
-
-    // Are they requesting a child of our
-    // origin? If not, handle the mishap
-    // gracefully.
-    if (this.origin !== '.') {
-      const zone = util.from(name, labels, -this.count);
-
-      // Refer them back to the root zone.
-      if (!util.equal(zone, this.origin)) {
-        const [ns, ar] = this.getHints();
-        return [[], ns, ar, false, true];
-      }
+      return [an, ns, ar, true, true];
     }
 
     // Couldn't find anything.
     // Serve an SoA (no data).
-    if (labels.length === this.count) {
+    if (authority) {
       const ns = this.get(this.origin, types.SOA);
       this.proveNoData(ns);
       return [[], ns, [], true, false];
@@ -284,13 +299,18 @@ class Zone {
     // might have a referral for.
     const index = this.count + 1;
     const child = util.from(name, labels, -index);
-    const [ns, glue] = this.find(child, types.NS);
+    [ns, glue] = this.find(child, types.NS);
 
     // Couldn't find any nameservers.
     // Serve an SoA (nxdomain).
     if (ns.length === 0) {
-      const ns = this.get(this.origin, types.SOA);
-      this.proveNameError(child, ns);
+      let ns = [];
+      // The root zone can prove the TLD doesn't exist with authority
+      // but regular authoritative name servers should be as quiet as possible.
+      if (this.origin === '.') {
+        ns = this.get(this.origin, types.SOA);
+        this.proveNameError(child, ns);
+      }
       return [[], ns, [], false, false];
     }
 
@@ -348,11 +368,12 @@ class Zone {
  */
 
 class RecordMap {
-  constructor() {
+  constructor(zone) {
     // type -> rrs
     this.rrs = new Map();
     // type covered -> sigs
     this.sigs = new Map();
+    this.zone = zone;
   }
 
   clear() {
@@ -388,24 +409,94 @@ class RecordMap {
     return this;
   }
 
+  filterMatches(name, rrs) {
+    const ret = [];
+
+    for (const rr of rrs) {
+      if (!isWild(rr.name)) {
+        ret.push(rr);
+        continue;
+      }
+
+      const x = util.splitName(name);
+      const y = util.splitName(rr.name);
+
+      if (x.length < y.length)
+        continue;
+
+      // Remove '*' label and test remainder
+      y.shift();
+
+      let push = true;
+      for (let i = 1; i <= y.length; i++) {
+        if (y[y.length - i] !== x[x.length - i]) {
+          push = false;
+          break;
+        }
+      }
+      if (!push)
+        continue;
+
+      ret.push(rr);
+    }
+
+    return ret;
+  }
+
   push(name, type, an) {
     assert(util.isFQDN(name));
     assert((type & 0xffff) === type);
     assert(Array.isArray(an));
 
-    const rrs = this.rrs.get(type);
+    // If a name has a CNAME record, there should be no
+    // other records for that name in the zone.
+    // (RFC 1034 section 3.6.2, RFC 1912 section 2.4)
+    if (type !== types.CNAME) {
+      let rrs = this.rrs.get(types.CNAME);
 
-    if (!rrs || rrs.length === 0)
-      return this;
+      if (rrs && rrs.length > 0) {
+        rrs = this.filterMatches(name, rrs);
+        for (const rr of rrs)
+          an.push(convert(name, rr));
 
-    for (const rr of rrs)
-      an.push(convert(name, rr));
+        let sigs = this.sigs.get(types.CNAME);
 
-    const sigs = this.sigs.get(type);
+        if (sigs) {
+          sigs = this.filterMatches(name, sigs);
+          for (const rr of sigs)
+            an.push(convert(name, rr));
+        }
 
-    if (sigs) {
-      for (const rr of sigs)
+        if (!sigs && this.zone.zskkey && this.zone.zskpriv) {
+          // Create dnssec sig on the fly (especially useful for wildcard)
+          const sig = dnssec.sign(this.zone.zskkey, this.zone.zskpriv, an);
+          an.push(sig);
+        }
+
+        return this;
+      }
+    }
+
+    let rrs = this.rrs.get(type);
+
+    if (rrs && rrs.length > 0) {
+      rrs = this.filterMatches(name, rrs);
+      for (const rr of rrs)
         an.push(convert(name, rr));
+
+      let sigs = this.sigs.get(type);
+
+      if (sigs) {
+        sigs = this.filterMatches(name, sigs);
+        for (const rr of sigs)
+          an.push(convert(name, rr));
+      }
+
+      if (!sigs && this.zone.zskkey && this.zone.zskpriv) {
+        // Create dnssec sig on the fly (especially useful for wildcard)
+        const sig = dnssec.sign(this.zone.zskkey, this.zone.zskpriv, an);
+        an.push(sig);
+      }
     }
 
     return this;
@@ -527,19 +618,9 @@ function convert(name, rr) {
   if (!isWild(rr.name))
     return rr;
 
-  const x = util.splitName(name);
-  const y = util.splitName(rr.name);
-
-  assert(y.length > 0);
-
-  if (x.length < y.length)
-    return rr;
-
   rr = rr.clone();
 
-  y[0] = x[x.length - y.length];
-
-  rr.name = `${y.join('.')}.`;
+  rr.name = name;
 
   return rr;
 }