FTL internal package dump (#638)

* FTL internal package dump

Signed-off-by: Christian König <ckoenig@posteo.de>

* Shorten name

Signed-off-by: Christian König <ckoenig@posteo.de>

* Restructure FTL menu

Signed-off-by: Christian König <ckoenig@posteo.de>

docs/ftldns/package_dump.md

@@ -0,0 +1,34 @@
+## Pi-hole FTL's internal pcap packet dump
+
+Pi-hole has its own embedded package dumping. It can be enabled by adding the following to a file like `/etc/dnsmasq.d/99-record.conf`:
+
+```
+dumpfile=/etc/pihole/dump.pcap
+```
+
+(or any other location you prefer), in addition to
+
+```
+dumpmask=<mask>
+```
+
+where `mask` specifies which types of packets should be added to the dumpfile defined above. The argument should be the OR of the bitmasks for each type of packet to be dumped: it can be specified in hex by preceding the number with 0x in the normal way.
+Each time a packet is written to the dumpfile, we log the packet sequence and the mask representing its type. The current types are:
+
+- `0x0001` - DNS queries from clients
+- `0x0002` - DNS replies to clients
+- `0x0004` - DNS queries to upstream
+- `0x0008` - DNS replies from upstream
+- `0x0010` - queries send upstream for DNSSEC validation
+- `0x0020` - replies to queries for DNSSEC validation
+- `0x0040` - replies to client queries which fail DNSSEC validation
+- `0x0080` - replies to queries for DNSSEC validation which fail validation.
+
+If you just want to record everything and later filter this in Wireshark you can just add the two lines
+
+```
+dumpfile=/etc/pihole/dump.pcap
+dumpmask=0x00ff
+```
+
+{!abbreviations.md!}

mkdocs.yml

@@ -108,16 +108,18 @@ nav:
     - 'DNS cache': ftldns/dns-cache.md
     - 'Blocking mode': ftldns/blockingmode.md
     - 'Privacy levels': ftldns/privacylevels.md
-    - 'Telnet API': ftldns/telnet-api.md
-    - 'Signals': 'ftldns/signals.md'
     - 'Compatibility': ftldns/compatibility.md
-    - 'Install from source': ftldns/compile.md
     - 'dnsmasq warnings': ftldns/dnsmasq_warn.md
-    - 'Cache dump': ftldns/cache_dump.md
-    - 'Debugging FTLDNS':
-      - 'gdb': ftldns/debugging.md
-      - 'valgrind': ftldns/valgrind.md
-    - 'In-depth manual': ftldns/in-depth.md
+    - 'Advanced':
+        - 'Install from source': ftldns/compile.md
+        - 'Telnet API': ftldns/telnet-api.md
+        - 'Signals': 'ftldns/signals.md'
+        - 'Cache dump': ftldns/cache_dump.md
+        - 'Packet dump': ftldns/package_dump.md
+        - 'Debugging':
+            - 'gdb': ftldns/debugging.md
+            - 'valgrind': ftldns/valgrind.md
+        - 'In-depth manual': ftldns/in-depth.md
   - 'RegEx blocking':
     - "Overview": regex/overview.md
     - "Testing": regex/testmode.md