blob: 53d5b2dbf596b43b8b05b25169bfce8b6705cb39 [file] [log] [blame]
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package net
const hexDigit = "0123456789abcdef"
// A HardwareAddr represents a physical hardware address.
type HardwareAddr []byte
func (a HardwareAddr) String() string {
if len(a) == 0 {
return ""
}
buf := make([]byte, 0, len(a)*3-1)
for i, b := range a {
if i > 0 {
buf = append(buf, ':')
}
buf = append(buf, hexDigit[b>>4])
buf = append(buf, hexDigit[b&0xF])
}
return string(buf)
}
// ParseMAC parses s as an IEEE 802 MAC-48, EUI-48, EUI-64, or a 20-octet
// IP over InfiniBand link-layer address using one of the following formats:
//
// 00:00:5e:00:53:01
// 02:00:5e:10:00:00:00:01
// 00:00:00:00:fe:80:00:00:00:00:00:00:02:00:5e:10:00:00:00:01
// 00-00-5e-00-53-01
// 02-00-5e-10-00-00-00-01
// 00-00-00-00-fe-80-00-00-00-00-00-00-02-00-5e-10-00-00-00-01
// 0000.5e00.5301
// 0200.5e10.0000.0001
// 0000.0000.fe80.0000.0000.0000.0200.5e10.0000.0001
func ParseMAC(s string) (hw HardwareAddr, err error) {
if len(s) < 14 {
goto error
}
if s[2] == ':' || s[2] == '-' {
if (len(s)+1)%3 != 0 {
goto error
}
n := (len(s) + 1) / 3
if n != 6 && n != 8 && n != 20 {
goto error
}
hw = make(HardwareAddr, n)
for x, i := 0, 0; i < n; i++ {
var ok bool
if hw[i], ok = xtoi2(s[x:], s[2]); !ok {
goto error
}
x += 3
}
} else if s[4] == '.' {
if (len(s)+1)%5 != 0 {
goto error
}
n := 2 * (len(s) + 1) / 5
if n != 6 && n != 8 && n != 20 {
goto error
}
hw = make(HardwareAddr, n)
for x, i := 0, 0; i < n; i += 2 {
var ok bool
if hw[i], ok = xtoi2(s[x:x+2], 0); !ok {
goto error
}
if hw[i+1], ok = xtoi2(s[x+2:], s[4]); !ok {
goto error
}
x += 5
}
} else {
goto error
}
return hw, nil
error:
return nil, &AddrError{Err: "invalid MAC address", Addr: s}
}