diff options
Diffstat (limited to 'utils')
| -rw-r--r-- | utils/net.go | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/utils/net.go b/utils/net.go index 76454bd..c69d90f 100644 --- a/utils/net.go +++ b/utils/net.go @@ -16,6 +16,13 @@ func (m *Mac) Format() string { m.Addr[0], m.Addr[1], m.Addr[2], m.Addr[3], m.Addr[4], m.Addr[5]) } +// Compact renders the MAC as 12 lowercase hex digits with no separators, the +// form used as a DNS label (e.g. aabbccddeeff). +func (m *Mac) Compact() string { + return fmt.Sprintf("%02x%02x%02x%02x%02x%02x", + m.Addr[0], m.Addr[1], m.Addr[2], m.Addr[3], m.Addr[4], m.Addr[5]) +} + // ParseMac reads a colon-separated hex MAC. It tolerates uppercase and the // zero-stripped octets macOS prints (e.g. "8:0:27:ab:cd:ef"). func ParseMac(s string) (*Mac, error) { @@ -32,6 +39,25 @@ func ParseMac(s string) (*Mac, error) { return mac, nil } +// ParseMacCompact reads the 12-hex-digit, separator-less form used as a DNS +// label (e.g. aabbccddeeff) back into a Mac. +func ParseMacCompact(s string) (*Mac, error) { + mac := &Mac{} + t := strings.TrimSpace(s) + if len(t) != 12 { + return nil, fmt.Errorf("invalid compact mac %q: want 12 hex digits, got %d", s, len(t)) + } + n, err := fmt.Sscanf(t, "%2x%2x%2x%2x%2x%2x", + &mac.Addr[0], &mac.Addr[1], &mac.Addr[2], &mac.Addr[3], &mac.Addr[4], &mac.Addr[5]) + if err != nil { + return nil, err + } + if n != 6 { + return nil, fmt.Errorf("invalid compact mac %q: parsed %d of 6 octets", s, n) + } + return mac, nil +} + // INet4 is an IPv4 address. type INet4 struct { Addr [4]byte |