From a616342e2e6643f8f41530686c7909ba74e2975e Mon Sep 17 00:00:00 2001
From: Jack O'Sullivan <jackos1998@gmail.com>
Date: Fri, 23 Aug 2019 12:55:35 +0100
Subject: [PATCH] Implement IpamDriver.GetDefaultAddressSpace

---
 Makefile         | 10 ++++++++--
 config.json      |  7 +++++++
 net-dhcp/ipam.py | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 requirements.txt |  2 ++
 4 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 4519aa3..ad40617 100644
--- a/Makefile
+++ b/Makefile
@@ -1,15 +1,17 @@
 PLUGIN_NAME = devplayer0/net-dhcp
 PLUGIN_TAG ?= latest
 
-all: clean rootfs create
+all: clean rootfs build create
 
 clean:
 	@echo "### rm ./plugin"
 	@rm -rf ./plugin
 
-rootfs:
+build:
 	@echo "### docker build: rootfs image with net-dhcp"
 	@docker build -t ${PLUGIN_NAME}:rootfs .
+
+rootfs:
 	@echo "### create rootfs directory in ./plugin/rootfs"
 	@mkdir -p ./plugin/rootfs
 	@docker create --name tmp ${PLUGIN_NAME}:rootfs
@@ -24,6 +26,10 @@ create:
 	@echo "### create new plugin ${PLUGIN_NAME}:${PLUGIN_TAG} from ./plugin"
 	@docker plugin create ${PLUGIN_NAME}:${PLUGIN_TAG} ./plugin
 
+debug:
+	@docker run --rm -ti --cap-add CAP_SYS_ADMIN --network host --volume /run/docker/plugins:/run/docker/plugins \
+		--volume /run/docker.sock:/run/docker.sock ${PLUGIN_NAME}:rootfs
+
 enable:		
 	@echo "### enable plugin ${PLUGIN_NAME}:${PLUGIN_TAG}"		
 	@docker plugin enable ${PLUGIN_NAME}:${PLUGIN_TAG}
diff --git a/config.json b/config.json
index 6b8f5c2..7c6e6bf 100644
--- a/config.json
+++ b/config.json
@@ -12,6 +12,13 @@
     "network": {
         "type": "host"
     },
+    "mounts": [
+        {
+            "source": "/var/run/docker.sock",
+            "destination": "/run/docker.sock",
+            "type": "bind"
+        }
+    ],
     "linux": {
         "capabilities": [
             "CAP_SYS_ADMIN"
diff --git a/net-dhcp/ipam.py b/net-dhcp/ipam.py
index 1f10bdf..3b91fde 100644
--- a/net-dhcp/ipam.py
+++ b/net-dhcp/ipam.py
@@ -1,10 +1,58 @@
+import itertools
+import ipaddress
+from os import path
+import atexit
+
+import pyroute2
+import docker
 from flask import jsonify
 
 from . import app
 
+ipdb = pyroute2.IPDB()
+@atexit.register
+def close_ipdb():
+    ipdb.release()
+
+client = docker.from_env()
+@atexit.register
+def close_docker():
+    client.close()
+
+def iface_addrs(iface):
+    return list(map(ipaddress.ip_interface, iface.ipaddr.ipv4))
+def iface_nets(iface):
+    return list(map(lambda n: n.network, map(ipaddress.ip_interface, iface.ipaddr.ipv4)))
+
+def get_bridges():
+    reserved_nets = set(map(ipaddress.ip_network, map(lambda c: c['Subnet'], \
+        itertools.chain.from_iterable(map(lambda i: i['Config'], filter(lambda i: i['Driver'] != 'net-dhcp', \
+            map(lambda n: n.attrs['IPAM'], client.networks.list())))))))
+
+    return list(filter(lambda i: i.kind == 'bridge' and not set(iface_nets(i)).intersection(reserved_nets), \
+        map(lambda i: ipdb.interfaces[i], filter(lambda k: isinstance(k, str), ipdb.interfaces.keys()))))
+
 @app.route('/IpamDriver.GetCapabilities')
 def ipam_get_capabilities():
     return jsonify({
         'RequiresMACAddress': True,
         'RequiresRequestReplay': False
+    })
+
+@app.route('/IpamDriver.GetDefaultAddressSpace')
+def get_default_addr_space():
+    bridges = get_bridges()
+    if not bridges:
+        return jsonify({'Err': 'No bridges available'}), 404
+
+    first = None
+    for b in bridges:
+        if b.ipaddr.ipv4:
+            first = b
+    if not first:
+        return jsonify({'Err': 'No bridges with addresses available'}), 404
+
+    return jsonify({
+        'LocalDefaultAddressSpace': f'{first.ifname}-{iface_addrs(first)[0].network}',
+        'GlobalDefaultAddressSpace': None
     })
\ No newline at end of file
diff --git a/requirements.txt b/requirements.txt
index f2ab4a0..5d73c45 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,4 @@
 flask==1.1.1
 gunicorn==19.9.0
+pyroute2==0.5.6
+docker==4.0.2
\ No newline at end of file