Packetbeat: add support for EDNS/DNSSEC

* Add EDNS OPT meta-RR information in `dns.opt` field
* Document EDNS fields
* Do some EDNS checks (UDP packet size, OPT RR present in request and response)
* Update vendor miekg/dns (EDNS fix)

* Add DNSSEC RRs
* Add new tests: begin `names_test.go` for RRs specific tests

* Refactor rrToMapStr/rrToString to use only one switch case
* Instantiate a logp.MakeDebug and use it throughout the dns package

CHANGELOG.asciidoc

@@ -185,6 +185,7 @@ https://github.com/elastic/beats/compare/v1.2.0...5.0.0-alpha1[View commits]
 
 - Change the DNS library used throughout the dns package to github.com/miekg/dns. {pull}803[803]
 - Add support for NFS v3 and v4. {pull}1231[1231]
+- Add support for EDNS and DNSSEC. {pull}1292[1292]
 
 *Topbeat*
 

glide.yaml

@@ -42,7 +42,7 @@ import:
 - package: github.com/go-ole/go-ole
   version: v1.2.0
 - package: github.com/miekg/dns
-  version: 85b661b2a6fc95a5a83e66d7730c4bc0b6e9c99e
+  version: c9d1302d540edfb97d9ecbfe90b4fb515088630b
 - package: github.com/Shopify/sarama
   version: v1.8.0
 - package: github.com/klauspost/crc32

packetbeat/docs/fields.asciidoc

@@ -638,6 +638,30 @@ The time interval in seconds that this resource record may be cached before it s
 The data describing the resource. The meaning of this data depends on the type and class of the resource record.
 
 
+==== dns.opt.version
+
+example: 0
+
+The EDNS version.
+
+==== dns.opt.do
+
+type: bool
+
+If set, the transaction uses DNSSEC.
+
+==== dns.opt.ext_rcode
+
+example: BADVERS
+
+Extended response code field.
+
+==== dns.opt.udp_size
+
+type: int
+
+Requestor's UDP payload size (in bytes).
+
 === amqp Fields
 
 AMQP specific event fields.

packetbeat/etc/fields.yml

@@ -644,6 +644,22 @@ trans_event:
             The data describing the resource. The meaning of this data depends
             on the type and class of the resource record.
 
+        - name: opt.version
+          description: The EDNS version.
+          example: "0"
+
+        - name: opt.do
+          type: bool
+          description: If set, the transaction uses DNSSEC.
+
+        - name: opt.ext_rcode
+          description: Extended response code field.
+          example: "BADVERS"
+
+        - name: opt.udp_size
+          type: int
+          description: Requestor's UDP payload size (in bytes).
+
     - name: amqp
       type: group
       description: AMQP specific event fields.

packetbeat/protos/dns/README.md

@@ -35,8 +35,6 @@ When response error Notes are linked to the previous request, the transaction is
 
 **General**
 * Publish an event with Notes when a Query or a lone Response cannot be decoded.
-* Add EDNS and DNSSEC support (consider using miekg/dns instead
-  of gopacket).
 * Consider adding ICMP support to
      - correlate ICMP type 3, code 4 (datagram too big) with DNS messages,
      - correlate ICMP type 3, code 13 (administratively prohibited) or