diff options
Diffstat (limited to 'dhcpv4/option_vivc.go')
| -rw-r--r-- | dhcpv4/option_vivc.go | 39 |
1 files changed, 9 insertions, 30 deletions
diff --git a/dhcpv4/option_vivc.go b/dhcpv4/option_vivc.go index 7576637..4ff42a3 100644 --- a/dhcpv4/option_vivc.go +++ b/dhcpv4/option_vivc.go @@ -4,6 +4,8 @@ import ( "bytes" "encoding/binary" "fmt" + + "github.com/u-root/u-root/pkg/uio" ) // This option implements the Vendor-Identifying Vendor Class Option @@ -23,39 +25,16 @@ type OptVIVC struct { // ParseOptVIVC contructs an OptVIVC tsruct from a sequence of bytes and returns // it, or an error. func ParseOptVIVC(data []byte) (*OptVIVC, error) { - if len(data) < 2 { - return nil, ErrShortByteStream - } - code := OptionCode(data[0]) - if code != OptionVendorIdentifyingVendorClass { - return nil, fmt.Errorf("expected code %v, got %v", OptionVendorIdentifyingVendorClass, code) - } - - length := int(data[1]) - if len(data) < 2+length { - return nil, ErrShortByteStream - } - data = data[2:length+2] - - ids := []VIVCIdentifier{} - for len(data) > 5 { - entID := binary.BigEndian.Uint32(data[0:4]) - idLen := int(data[4]) - data = data[5:] - - if idLen > len(data) { - return nil, ErrShortByteStream - } - - ids = append(ids, VIVCIdentifier{EntID: entID, Data: data[:idLen]}) - data = data[idLen:] - } + buf := uio.NewBigEndianBuffer(data) - if len(data) != 0 { - return nil, ErrShortByteStream + var ids []VIVCIdentifier + for buf.Has(5) { + entID := buf.Read32() + idLen := int(buf.Read8()) + ids = append(ids, VIVCIdentifier{EntID: entID, Data: buf.CopyN(idLen)}) } - return &OptVIVC{Identifiers: ids}, nil + return &OptVIVC{Identifiers: ids}, buf.FinError() } // Code returns the option code. |