Dan Williams d5acb127b8 spec/plugins: return interface details and multiple IP addresses to runtime
Updates the spec and plugins to return an array of interfaces and IP details
to the runtime including:

- interface names and MAC addresses configured by the plugin
- whether the interfaces are sandboxed (container/VM) or host (bridge, veth, etc)
- multiple IP addresses configured by IPAM and which interface they
have been assigned to

Returning interface details is useful for runtimes, as well as allowing
more flexible chaining of CNI plugins themselves.  For example, some
meta plugins may need to know the host-side interface to be able to
apply firewall or traffic shaping rules to the container.
2017-01-25 11:31:18 -06:00
..

host-local IP address manager

host-local IPAM allocates IPv4 and IPv6 addresses out of a specified address range. Optionally, it can include a DNS configuration from a resolv.conf file on the host.

Usage

Obtain an IP

Given the following network configuration:

{
    "name": "default",
    "ipam": {
        "type": "host-local",
        "subnet": "203.0.113.0/24"
    }
}

Using the command line interface

$ export CNI_COMMAND=ADD
$ export CNI_CONTAINERID=f81d4fae-7dec-11d0-a765-00a0c91e6bf6
$ ./host-local < $conf
{
    "ip4": {
        "ip": "203.0.113.1/24"
    }
}

Backends

By default ipmanager stores IP allocations on the local filesystem using the IP address as the file name and the ID as contents. For example:

$ ls /var/lib/cni/networks/default
203.0.113.1	203.0.113.2
$ cat /var/lib/cni/networks/default/203.0.113.1
f81d4fae-7dec-11d0-a765-00a0c91e6bf6

Configuration Files

{
	"name": "ipv6",
    "ipam": {
		"type": "host-local",
		"subnet": "3ffe:ffff:0:01ff::/64",
		"rangeStart": "3ffe:ffff:0:01ff::0010",
		"rangeEnd": "3ffe:ffff:0:01ff::0020",
		"routes": [
			{ "dst": "3ffe:ffff:0:01ff::1/64" }
		],
		"resolvConf": "/etc/resolv.conf"
	}
}
{
    "name": "ipv4",
	"ipam": {
		"type": "host-local",
		"subnet": "203.0.113.1/24",
		"rangeStart": "203.0.113.10",
		"rangeEnd": "203.0.113.20",
		"routes": [
			{ "dst": "203.0.113.0/24" }
		]
	}
}