Stefan Junker 7ea07a6405 pkg/ipam{,test}: improve error handling and tests
* _suite.go and _test.go file should be in the same package, using the
  _test package for that, which requires some fields and methods to be
  exported
* Introduce error type for cleaner error handling
* test adaptions for error type checking
2016-07-22 15:17:22 -07:00

132 lines
3.6 KiB
Go

// Copyright 2015 CNI authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package ipam
import (
"fmt"
"os"
"github.com/containernetworking/cni/pkg/invoke"
"github.com/containernetworking/cni/pkg/ip"
"github.com/containernetworking/cni/pkg/types"
"github.com/vishvananda/netlink"
"net"
"strconv"
"strings"
)
const (
// private mac prefix safe to use
PrivateMACPrefix = "0a:58"
// veth link dev type
vethLinkType = "veth"
)
func ExecAdd(plugin string, netconf []byte) (*types.Result, error) {
return invoke.DelegateAdd(plugin, netconf)
}
func ExecDel(plugin string, netconf []byte) error {
return invoke.DelegateDel(plugin, netconf)
}
// ConfigureIface takes the result of IPAM plugin and
// applies to the ifName interface
func ConfigureIface(ifName string, res *types.Result) error {
link, err := netlink.LinkByName(ifName)
if err != nil {
return fmt.Errorf("failed to lookup %q: %v", ifName, err)
}
if err := netlink.LinkSetUp(link); err != nil {
return fmt.Errorf("failed to set %q UP: %v", ifName, err)
}
// only set hardware address to veth when using ipv4
if link.Type() == vethLinkType && res.IP4 != nil {
hwAddr, err := GenerateHardwareAddr4(res.IP4.IP.IP, PrivateMACPrefix)
if err != nil {
return fmt.Errorf("failed to generate hardware addr: %v", err)
}
if err = netlink.LinkSetHardwareAddr(link, hwAddr); err != nil {
return fmt.Errorf("failed to add hardware addr to %q: %v", ifName, err)
}
}
// TODO(eyakubovich): IPv6
addr := &netlink.Addr{IPNet: &res.IP4.IP, Label: ""}
if err = netlink.AddrAdd(link, addr); err != nil {
return fmt.Errorf("failed to add IP addr to %q: %v", ifName, err)
}
for _, r := range res.IP4.Routes {
gw := r.GW
if gw == nil {
gw = res.IP4.Gateway
}
if err = ip.AddRoute(&r.Dst, gw, link); err != nil {
// we skip over duplicate routes as we assume the first one wins
if !os.IsExist(err) {
return fmt.Errorf("failed to add route '%v via %v dev %v': %v", r.Dst, gw, ifName, err)
}
}
}
return nil
}
type SupportIp4OnlyErr struct{ msg string }
func (e SupportIp4OnlyErr) Error() string { return e.msg }
type MacParseErr struct{ msg string }
func (e MacParseErr) Error() string { return e.msg }
type InvalidPrefixLengthErr struct{ msg string }
func (e InvalidPrefixLengthErr) Error() string { return e.msg }
// GenerateHardwareAddr4 generates 48 bit virtual mac addresses based on the IP4 input.
func GenerateHardwareAddr4(ip net.IP, prefix string) (net.HardwareAddr, error) {
switch {
case ip.To4() == nil:
return nil, SupportIp4OnlyErr{msg: "GenerateHardwareAddr4 only supports valid IPv4 address as input"}
case len(prefix) != len(PrivateMACPrefix):
return nil, InvalidPrefixLengthErr{msg: fmt.Sprintf(
"Prefix has length %d instead of %d", len(prefix), len(PrivateMACPrefix)),
}
}
mac := prefix
sections := strings.Split(ip.String(), ".")
for _, s := range sections {
i, _ := strconv.Atoi(s)
mac = mac + ":" + fmt.Sprintf("%02x", i)
}
hwAddr, err := net.ParseMAC(mac)
if err != nil {
return nil, MacParseErr{msg: fmt.Sprintf(
"Failed to parse mac address %q generated based on IP %q due to: %v", mac, ip, err),
}
}
return hwAddr, nil
}