node: rpc dumpzone

Co-authored-by: James Stevens <github@jrcs.net>
Co-authored-by: Mark Tyneway <mark.tyneway@gmail.com>

lib/node/rpc.js

@@ -6,6 +6,10 @@
 
 'use strict';
 
+const constants = require('bns/lib/constants');
+const {types} = constants;
+const fs = require('fs');
+const bns = require('bns');
 const assert = require('bsert');
 const bweb = require('bweb');
 const {Lock} = require('bmutex');
@@ -246,6 +250,7 @@ class RPC extends RPCBase {
     this.add('validateresource', this.validateResource);
 
     this.add('resetrootcache', this.resetRootCache);
+    this.add('dumpzone', this.dumpzone);
 
     // Compat
     // this.add('getnameinfo', this.getNameInfo);
@@ -2533,6 +2538,67 @@ class RPC extends RPCBase {
     return null;
   }
 
+ async dumpzone(args, help) {
+    if (help || args.length !== 1)
+      throw new RPCError(errs.MISC_ERROR, 'dumpzone <filename>');
+
+    const valid = new Validator(args);
+    const filename = valid.str(0, null);
+    if (filename == null)
+      throw new RPCError(errs.MISC_ERROR, 'dumpzone <filename>');
+
+    const tmp = filename + '~';
+    this.logger.debug(`dumping root zone to file: ${filename}`);
+
+    let fd = null;
+    let fileErr = null;
+    fd = fs.createWriteStream(tmp, { flags: 'a+' });
+    fd.on('error', (err) => {
+      fd.end();
+      fd = null;
+      fileErr = err;
+    });
+
+    const tree = this.chain.db.tree;
+    const iter = tree.iterator(true);
+
+    let count = 0;
+    while ((await iter.next()) && (fd != null)) {
+      count++;
+      if (count % 10000 === 0)
+        this.logger.debug('dumpzone names processed: %d', count);
+
+      if (fd == null)
+        break;
+
+      const {value} = iter;
+      const ns = NameState.decode(value);
+
+      if (ns.data.length <= 0)
+        continue;
+
+      const fqdn = bns.util.fqdn(ns.name.toString('ascii'));
+      const resource = Resource.decode(ns.data);
+      for (const rr of resource.records) {
+        if (fd == null)
+          break;
+
+        if (rr.type !== types.RRSIG)
+          fd.write(rr.toDNS(fqdn).toString() + '\n');
+      }
+    }
+
+    if (fd == null)
+      return fileErr;
+
+    fd.end();
+    fs.renameSync(tmp, filename);
+
+    this.logger.debug('root zone dump complete. Total names: %d', count);
+
+    return filename;
+  }
+
   /*
    * Helpers
    */