8b43e90949
git-subtree-dir: pkg git-subtree-mainline: dcf7368eeab15e2affc6256f0bb1e84dd46a34de git-subtree-split: a11be4d7596203874b742b6597caf255204c56c3
64 lines
1.7 KiB
Go
64 lines
1.7 KiB
Go
// Copyright 2016 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 hwaddr
|
|
|
|
import (
|
|
"fmt"
|
|
"net"
|
|
)
|
|
|
|
const (
|
|
ipRelevantByteLen = 4
|
|
PrivateMACPrefixString = "0a:58"
|
|
)
|
|
|
|
var (
|
|
// private mac prefix safe to use
|
|
PrivateMACPrefix = []byte{0x0a, 0x58}
|
|
)
|
|
|
|
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 []byte) (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)),
|
|
}
|
|
}
|
|
|
|
ipByteLen := len(ip)
|
|
return (net.HardwareAddr)(
|
|
append(
|
|
prefix,
|
|
ip[ipByteLen-ipRelevantByteLen:ipByteLen]...),
|
|
), nil
|
|
}
|