Make the container configurable via env variable; update documentation

.gitignore

@@ -1,52 +1 @@
-# Prerequisites
-*.d
-
-# Object files
-*.o
-*.ko
-*.obj
-*.elf
-
-# Linker output
-*.ilk
-*.map
-*.exp
-
-# Precompiled Headers
-*.gch
-*.pch
-
-# Libraries
-*.lib
-*.a
-*.la
-*.lo
-
-# Shared objects (inc. Windows DLLs)
-*.dll
-*.so
-*.so.*
-*.dylib
-
-# Executables
-*.exe
-*.out
-*.app
-*.i*86
-*.x86_64
-*.hex
-
-# Debug files
-*.dSYM/
-*.su
-*.idb
-*.pdb
-
-# Kernel Module Compile Results
-*.mod*
-*.cmd
-.tmp_versions/
-modules.order
-Module.symvers
-Mkfile.old
-dkms.conf
+*.tar

Dockerfile

@@ -1,20 +1,6 @@
-FROM alpine AS builder
-ARG MDNS_REPEATER_VERSION=local
-ADD mdns-repeater.c mdns-repeater.c
-RUN set -ex && \
-    apk add build-base && \
-    gcc -o /bin/mdns-repeater mdns-repeater.c -DMDNS_REPEATER_VERSION=\"${MDNS_REPEATER_VERSION}\"
-
-FROM alpine
-
-RUN set -ex && \
-    apk add vlan libcap bash
-COPY --from=builder /bin/mdns-repeater /bin/mdns-repeater
-RUN chmod +x /bin/mdns-repeater
-RUN setcap cap_net_raw=+ep /bin/mdns-repeater
+FROM monstrenyatko/mdns-repeater
 
 COPY run.sh /app/
 RUN chmod +x /app/run.sh
 
 ENTRYPOINT ["/app/run.sh"]
-CMD ["/bin/mdns-repeater", "-f", "eth0.20", "eth0.100"]

Makefile

@@ -0,0 +1,14 @@
+container_name := mdns-repeater
+repo_name := mag1024/mikrotik-docker-mdns-repeater
+
+default: container/arm64
+all: container/arm64 container/arm-v6
+clean:
+	rm -f *.tar
+
+container/%:
+	docker buildx build --load --platform linux/$(subst -,/,$*) -t $(container_name) .
+	docker save $(container_name) -o $(container_name)-$*.tar
+
+push:
+	docker buildx build --platform linux/arm64,linux/arm/v6 --push github.com/$(repo_name) -t $(repo_name):latest

README.md

@@ -1,82 +1,69 @@
 # docker-mdns-repeater-mikrotik
-mdns-repeater in mikrotik container
+An mDNS repeater that can ran as a container on Mikrotik routers.
 
 Based on:
-https://github.com/geekman/mdns-repeater
-https://github.com/monstrenyatko/docker-mdns-repeater
+* [geekman/mdns-repeater](https://github.com/geekman/mdns-repeater)
+* [monstrenyatko/docker-mdns-repeater](https://github.com/monstrenyatko/docker-mdns-repeater)
+* [TheMickeyMike/docker-mdns-repeater-mikrotik](https://github.com/TheMickeyMike/docker-mdns-repeater-mikrotik)
 
-This is work in progress, but you can base your config on that.
+Images availabe on Dockerhub at [mag1024/mikrotik-docker-mdns-repeater](https://hub.docker.com/repository/docker/mag1024/mikrotik-docker-mdns-repeater).
 
-## Mikrotik config
-Based on official docs https://help.mikrotik.com/docs/display/ROS/Container
-Instead of adding `veth2` to docker bridge i've added it to my home-lan bridge `BR1`.
-Veth2 is added as tagged port with two vlans (20,100), so in container on `eth0` i will create two vlan interfaces `eth0.20` and `eth0.100` with active dhcp client for IP leese, please look at `run.sh`.
+## How it works
+As of Oct 2022, the Mikrotik container implementation is limited to exactly one
+network interface. There is no option for an equivalent of 'host' mode
+networking, and the interface must be of type veth, so we have to get creative
+to get a functional repeater. The key is to attach the venth to a trunk bridge
+that contains multiple vlans corresponding to the networks we want to repeat
+across, and then create interfaces for each of the vlans inside the container,
+using the veth as the parent. The set of vlans/interfaces to use is specified
+via the _REPEATER_INTERFACES_ env variable, and the container runs a dhcp client
+to obtain an IP for each of them.
 
-```
- /interface/bridge/port/print 
-Flags: I - INACTIVE; H - HW-OFFLOAD
-Columns: INTERFACE, BRIDGE, HW, PVID, PRIORITY, PATH-COST, INTERNAL-PATH-COST, HOR
-IZON
- #    INTERFACE  BRIDGE  HW   PVID  PRIORITY  PATH-COST  IN  HORIZON
-10    veth2      BR1             1  0x80             10  10  none
+## Setup
+Begin by following the [Mikrotik container
+documentation](https://help.mikrotik.com/docs/display/ROS/Container) to create
+the veth interface.  Instead of creating a separate docker bridge, assign the
+new interface as a 'tagged' port to the bridge containing the interfaces you
+wish to repeat across.  These interfaces can be vlan interfaces, or physical
+interfaces with pvid set -- depending on whether you use vlans for the rest of
+your network setup. Refer to the [Mikrotik bridge
+documentation](https://help.mikrotik.com/docs/display/ROS/Bridge+VLAN+Table) for
+more details.
 
+The following example uses _veth-trunk_ veth interface and _br-trunk_ bridge,
+configured with vlans 10, 11, 12.
 
-/interface/bridge/vlan/print
-Flags: D - DYNAMIC
-Columns: BRIDGE, VLAN-IDS, CURRENT-TAGGED, CURRENT-UNTAGGED
-#   BRIDGE  VLAN-IDS  CURRENT-TAGGED  CURRENT-UNTAGGED
-0   BR1          100  BR1                                                  
-                      veth2                           
-3   BR1           20  BR1                                                 
-                      veth2                                                    
-4 D BR1            1                  BR1                   
-                                      veth2 
+Note: The address here does not matter, but it must have one to make the
+interface 'active'.
+```
+/interface/veth/print
+Flags: X - disabled; R - running
+ 0  R name="veth-trunk" address=10.200.200.200/24 gateway=10.200.200.1
+```
+
+Note: Again, pvid of the _veth_ itself does not matter.
+```
+/interface/bridge/port/print
+Flags: I - INACTIVE; H - HW-OFFLOAD
+Columns: INTERFACE, BRIDGE, HW, PVID, PRIORITY, PATH-COST, INTERNAL-PATH-COST, HORIZON
+#    INTERFACE     BRIDGE    HW   PVID  PRIORITY  PATH-COST  INTERNAL-PATH-COST  HORIZON
+0  H ether2        br-trunk  yes    10  0x80             10                  10  none
+1  H ether3        br-trunk  yes    13  0x80             10                  10  none
+...
+8    veth-trunk    br-trunk        111  0x80             10                  10  none
 ```
 
-## Build & pack container
+Note: The name of the interface inside the container is always _eth0_.
 ```
-docker buildx build --no-cache --platform linux/arm/v6 -t mdns .
-docker save mdns -o mdns.tar
-8.8M mdns.tar # size after pack
+/container/envs/print
+ 0 name="repeater_envs" key="REPEATER_INTERFACES" value="eth0.10 eth0.11 eth0.12"
 ```
 
-## Logs from running container
+Note: you may have to set the registry first via `/container/config/set registry-url=https://registry-1.docker.io`.
+Note: `start-on-boot` is only available on Mikrotik 7.6+
 ```
-log print where topics~"container"
- jun/29 22:01:28 container,info,debug create interface eth0.20
- jun/29 22:01:28 container,info,debug bring up eth0.20 interface
- jun/29 22:01:28 container,info,debug /app/run.sh: line 25: kill: (19) - No such process
- jun/29 22:01:28 container,info,debug starting dhcp client on eth0.20
- jun/29 22:01:28 container,info,debug udhcpc: started, v1.35.0
- jun/29 22:01:29 container,info,debug udhcpc: broadcasting discover
- jun/29 22:01:29 container,info,debug udhcpc: broadcasting select for 10.0.20.27, server 10.0.20.1
- jun/29 22:01:29 container,info,debug udhcpc: lease of 10.0.20.27 obtained from 10.0.20.1, lease time 86400
- jun/29 22:01:29 container,info,debug create interface eth0.100
- jun/29 22:01:29 container,info,debug bring up eth0.100 interface
- jun/29 22:01:29 container,info,debug /app/run.sh: line 25: kill: (34) - No such process
- jun/29 22:01:29 container,info,debug starting dhcp client on eth0.100
- jun/29 22:01:29 container,info,debug udhcpc: started, v1.35.0
- jun/29 22:01:29 container,info,debug udhcpc: broadcasting discover
- jun/29 22:01:30 container,info,debug udhcpc: broadcasting select for 10.0.100.244, server 10.0.100.1
- jun/29 22:01:30 container,info,debug udhcpc: lease of 10.0.100.244 obtained from 10.0.100.1, lease time 86400
- jun/29 22:01:30 container,info,debug + exec /bin/mdns-repeater -f eth0.20 eth0.100
- jun/29 22:01:30 container,info,debug mdns-repeater: dev eth0.20 addr 10.0.20.27 mask 255.255.255.0 net 10.0.20.0
- jun/29 22:01:30 container,info,debug mdns-repeater: dev eth0.100 addr 10.0.100.244 mask 255.255.255.0 net 10.0.100.0
- jul/01 21:49:34 container,info,debug bring up eth0.20 interface
- jul/01 21:49:34 container,info,debug /app/run.sh: line 25: kill: (22) - No such process
- jul/01 21:49:34 container,info,debug starting dhcp client on eth0.20
- jul/01 21:49:34 container,info,debug udhcpc: started, v1.35.0
- jul/01 21:49:34 container,info,debug udhcpc: broadcasting discover
- jul/01 21:49:34 container,info,debug udhcpc: broadcasting select for 10.0.20.27, server 10.0.20.1
- jul/01 21:49:34 container,info,debug udhcpc: lease of 10.0.20.27 obtained from 10.0.20.1, lease time 86400
- jul/01 21:49:34 container,info,debug bring up eth0.100 interface
- jul/01 21:49:34 container,info,debug /app/run.sh: line 25: kill: (40) - No such process
- jul/01 21:49:34 container,info,debug starting dhcp client on eth0.100
- jul/01 21:49:34 container,info,debug udhcpc: started, v1.35.0
- jul/01 21:49:34 container,info,debug udhcpc: broadcasting discover
- jul/01 21:49:35 container,info,debug udhcpc: broadcasting select for 10.0.100.244, server 10.0.100.1
- jul/01 21:49:35 container,info,debug udhcpc: lease of 10.0.100.244 obtained from 10.0.100.1, lease time 86400
- jul/01 21:49:35 container,info,debug + exec /bin/mdns-repeater -f eth0.20 eth0.100
- jul/01 21:49:35 container,info,debug mdns-repeater: dev eth0.20 addr 10.0.20.27 mask 255.255.255.0 net 10.0.20.0
- jul/01 21:49:35 container,info,debug mdns-repeater: dev eth0.100 addr 10.0.100.244 mask 255.255.255.0 net 10.0.100.0
+/container/print
+ 0 ... tag="mag1024/mikrotik-docker-mdns-repeater:latest" os="linux"
+   arch="arm64" interface=veth-trunk envlist="repeater_envs" mounts="" dns="" hostname="mdns-repeater" logging=yes
+   start-on-boot=yes status=running
 ```